FN Thomson Reuters Web of Science™ VR 1.0 PT J AU PERAL, B WARD, CJ SANMILLAN, JL THOMAS, S STALLINGS, RL MORENO, F HARRIS, PC AF PERAL, B WARD, CJ SANMILLAN, JL THOMAS, S STALLINGS, RL MORENO, F HARRIS, PC TI EVIDENCE OF LINKAGE DISEQUILIBRIUM IN THE SPANISH POLYCYSTIC KIDNEY-DISEASE-I POPULATION SO AMERICAN JOURNAL OF HUMAN GENETICS LA English DT Article ID POLYMERASE CHAIN-REACTION; GENETIC-ANALYSIS; PKD1 LOCUS; CHROMOSOME-16; DNA; MARKER; IDENTIFICATION; COMPLEX; ALLELES; REGION AB Forty-one Spanish families with polycystic kidney disease 1 (PKD1) were studied for evidence of linkage disequilibrium between the disease locus and six closely linked markers. Four of these loci-three highly polymorphic microsatellites (SM6, CW3, and CW2) and an RFLP marker (BLu24)-are described for the first time in this report. Overall the results reveal many different haplotypes on the disease-carrying chromosome, suggesting a variety of independent PKD1 mutations. However, linkage disequilibrium was found between BLu24 and PKD1, and this was corroborated by haplotype analysis including the microsatellite polymorphisms. From this analysis a group of closely related haplotypes, consisting of four markers, was found on 40% of PKD1 chromosomes, although markers flanking this homogeneous region showed greater variability. This study has highlighted an interesting subpopulation of Spanish PKD1 chromosomes, many of which have a common origin, that may be useful for localizing the PKD1 locus more precisely. C1 JOHN RADCLIFFE HOSP,INST MOLEC MED,MRC,MOLEC HAEMATOL UNIT,OXFORD OX3 9DU,ENGLAND. HOSP RAMON Y CAJAL,UNIDAD GENET MOLEC,E-28034 MADRID,SPAIN. LOS ALAMOS NATL LAB,DIV LIFE SCI,LOS ALAMOS,NM. LOS ALAMOS NATL LAB,CTR HUMAN GENOME STUDIES,LOS ALAMOS,NM. RI Stallings, Raymond/A-7213-2008; San-Millan, Jose/F-9944-2015; Peral, Belen/F-4562-2015 OI Peral, Belen/0000-0003-4984-4020 NR 37 TC 63 Z9 68 U1 0 U2 3 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0002-9297 J9 AM J HUM GENET JI Am. J. Hum. Genet. PD MAY PY 1994 VL 54 IS 5 BP 899 EP 908 PG 10 WC Genetics & Heredity SC Genetics & Heredity GA NH394 UT WOS:A1994NH39400020 PM 7909986 ER PT J AU RENDIG, SV PAN, HL LONGHURST, JC AF RENDIG, SV PAN, HL LONGHURST, JC TI BRIEF MESENTERIC ISCHEMIA INCREASES PGE(2), BUT NOT PGI(2), IN INTESTINAL LYMPH OF CATS SO AMERICAN JOURNAL OF PHYSIOLOGY LA English DT Article DE ABDOMINAL VISCERAL AFFERENTS; VISCERAL REFLEXES; CARDIOVASCULAR REFLEXES; PROSTAGLANDINS ID AFFERENT-FIBERS; BRADYKININ; PROSTAGLANDINS; REFLEXES AB Mesenteric ischemia of short duration (5-10 min) can stimulate A delta- and C-fiber afferent nerve endings in the viscera to reflexly activate the cardiovascular system. The mechanism of activation of abdominal visceral afferents is probably multifactorial and may involve prostaglandins (PGs), which have been shown to directly stimulate and/or sensitize visceral afferents when administered exogenously. We hypothesized that brief visceral ischemia is accompanied by release of PGI(2) and PGE(2) into the interstitium, where these cyclooxygenase products could stimulate or sensitize visceral afferent nerve endings. Accordingly, we measured immunoreactive PGE(2) (iPGE(2)) and 6-keto-PGF(1 alpha) (i6-keto-PGF(1 alpha), the stable metabolite of PGI(2), in lymph draining the ischemic viscera as well as in portal venous blood. An intestinal lymph duct distal to the lymph node was cannulated in pentobarbital sodium-anesthetized cats. Lymph and plasma iPGE(2) and i6-keto-PGF(1 alpha), concentrations were measured by radioimmunoassay before, during, and immediately after a 5- to 10-min occlusion of the descending aorta. The i6-keto-PGF(1 alpha), concentration increased significantly (P < 0.001) in portal venous plasma (61 +/- 12 to 107 +/- 18 pg/0.1 ml; n = 14) but not in lymph (148 +/- 30 to 159 +/- 24 pg/0.1 ml; n = 16). In contrast, iPGE(2) concentration was significantly (P < 0.01) elevated in both venous plasma (156 +/- 16 to 207 +/- 26 pg/0.1 ml; n = 19) and lymph (520 +/- 48 to 590 ir 52 pg/0.1 mi; n = 20). The increase in PGI(2) concentration in venous plasma but not in lymph suggests that there is endothelial release of PGI(2) into the circulation during ischemia and that this prostanoid may not play an important role in stimulating nerve endings located in the interstitium. An ischemia-induced elevation of interstitial PGE(2) concentration, however, suggests that this PG is an important factor in the stimulation of visceral afferents during brief ischemia. C1 LAWRENCE LIVERMORE NATL LAB,SCH MED,DEPT INTERNAL MED,DIV CARDIOVASC MED,DAVIS,CA 95616. LAWRENCE LIVERMORE NATL LAB,SCH MED,DEPT HUMAN PHYSIOL,DAVIS,CA 95616. NR 21 TC 12 Z9 12 U1 0 U2 0 PU AMER PHYSIOLOGICAL SOC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0002-9513 J9 AM J PHYSIOL JI Am. J. Physiol. PD MAY PY 1994 VL 266 IS 5 BP R1692 EP R1696 PN 2 PG 5 WC Physiology SC Physiology GA NP996 UT WOS:A1994NP99600098 ER PT J AU BARTLETT, EJ BRODIE, JD SIMKOWITZ, P DEWEY, SL RUSINEK, H WOLF, AP FOWLER, JS VOLKOW, ND SMITH, G WOLKIN, A CANCRO, R AF BARTLETT, EJ BRODIE, JD SIMKOWITZ, P DEWEY, SL RUSINEK, H WOLF, AP FOWLER, JS VOLKOW, ND SMITH, G WOLKIN, A CANCRO, R TI EFFECTS OF HALOPERIDOL CHALLENGE ON REGIONAL CEREBRAL GLUCOSE-UTILIZATION IN NORMAL HUMAN-SUBJECTS SO AMERICAN JOURNAL OF PSYCHIATRY LA English DT Article ID POSITRON EMISSION TOMOGRAPHY; D2-DOPAMINE RECEPTOR OCCUPANCY; SCHIZOPHRENIC-PATIENTS; METABOLIC-RATE; BASAL GANGLIA; 3-DIMENSIONAL REGISTRATION; DOPAMINE HYPOTHESIS; CLINICAL-RESPONSE; BRAIN-FUNCTION; TIME COURSE AB Objective: Positron emission tomography and the fluorodeoxyglucose (FDG) method were used to determine the brain's metabolic response to neuroleptic challenge in a normal, disease-free state. Method: FDG measurements were obtained before and 12 hours after administration of 5 mg of haloperidol to 12 young normal men. These values were compared with test-retest FDG measures obtained from nine normal male control subjects who received no drug intervention. Results: After haloperidol administration, the haloperidol subjects showed significantly lower glucose utilization in the neocortex, limbic cortex, thalamus, and caudate nucleus but not in the putamen or cerebellum. After adjustment for global effects, significant reductions were still evident in the frontal, occipital, and anterior cingulate cortex, whereas the putamen and cerebellum showed significant increases. Conclusions: This study, measuring the brain's metabolic response to acute receptor blockade, is a first step in the development of an assay of CNS pharmacological activity. By determining the response to neuroleptic challenge in a normal state, the study establishes a comparison group for determining response to challenge in various psychiatric conditions. C1 NYU,MED CTR,DEPT PSYCHIAT,NEW YORK,NY 10016. NYU,MED CTR,DEPT RADIOL,NEW YORK,NY 10016. BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. FU NCRR NIH HHS [RR-00096]; NIMH NIH HHS [NIMH MH-47277]; NINDS NIH HHS [NS-15638] NR 39 TC 81 Z9 81 U1 0 U2 0 PU AMER PSYCHIATRIC ASSOCIATION PI WASHINGTON PA 1400 K ST NW, WASHINGTON, DC 20005 SN 0002-953X J9 AM J PSYCHIAT JI Am. J. Psychiat. PD MAY PY 1994 VL 151 IS 5 BP 681 EP 686 PG 6 WC Psychiatry SC Psychiatry GA NJ089 UT WOS:A1994NJ08900009 PM 8166309 ER PT J AU MACK, GH COLE, DR JAMES, WC GIORDANO, TH SALYARDS, SL AF MACK, GH COLE, DR JAMES, WC GIORDANO, TH SALYARDS, SL TI STABLE OXYGEN AND CARBON ISOTOPES OF PEDOGENIC CARBONATE AS INDICATORS OF PLIOPLEISTOCENE PALEOCLIMATE IN THE SOUTHERN RIO-GRANDE RIFT, SOUTH-CENTRAL NEW-MEXICO SO AMERICAN JOURNAL OF SCIENCE LA English DT Article ID NORTHERN HEMISPHERE CLIMATE; K-AR DATES; GREAT-BASIN; PALOMAS FORMATIONS; AMERICAN WEST; UNITED-STATES; CAMP RICE; EVOLUTION; REGIMES; WATERS AB Stable oxygen and carbon isotopes of pedogenic carbonate provide a detailed record of paleoclimatic changes from late Pliocene through early Pleistocene in the Rio Grande rift of south-central New Mexico. A total of 30 calcic paleosols were sampled at three stratigraphic sections of the fluvial lithofacies of the Camp Rice Formation, and one calcic paleosol was sampled from fluvial sediment inset against the Camp Rice Formation. Paleosols commonly consist of an argillic B horizon (Bt) overlying a calcic (Bk) or petrocalcic (Km) horizon. The majority of paleosols consist of stage II morphology calcic horizons, although one stage V horizon and five stage III horizons were also sampled. Reversal magnetostratigraphy at all four sample sites bracket the age of the paleosol-bearing strata between 3.4 and 0.7 Ma and allow estimates of the absolute age of individual paleosols. Three paleoclimatic stages are indicated by the carbon and oxygen isotopic data from south-central New Mexico. The initial stage, from 3.1 to 2.5 Ma, was characterized by the overall lowest values of partial derivative O-18 and partial derivative C-13 and by an increase in values with decreasing age, suggesting high effective moisture and abundant winter precipitation, which decreased through time, and/or relatively low temperature, which increased through time. The second stage (2.5-1.4 Ma) displays an increase in partial derivative O-18 with decreasing age but no significant change in partial derivative C-13 with time, suggesting that the effective moisture was nearly constant, but that temperature and/or summer precipitation may have increased through time. The final stage (1.4-0.7 Ma) shows an overall increase in both partial derivative O-18 and partial derivative C-13 with decreasing age corresponding to less effective moisture, higher temperature, and/or greater summer precipitation through time. Plio-Pleistocene paleoclimatic changes in south-central New Mexico correlate well with paleoclimatic data elsewhere in the southwestern United States and adjacent Great Plains and may have been influenced by the onset of Northern Hemisphere continental glaciation, rise of the Sierra Nevada and Transverse Ranges, and/or broad regional uplift of the western United States. C1 OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831. OHIO STATE UNIV,DEPT GEOL SCI,COLUMBUS,OH 43210. UNIV CALIF LOS ANGELES,DEPT EARTH & SPACE SCI,LOS ANGELES,CA 90024. RP MACK, GH (reprint author), NEW MEXICO STATE UNIV,DEPT GEOL SCI,LAS CRUCES,NM 88003, USA. NR 56 TC 25 Z9 26 U1 0 U2 6 PU KLINE GEOLOGY LABORATORY PI NEW HAVEN PA YALE UNIV, NEW HAVEN, CT 06520 SN 0002-9599 J9 AM J SCI JI Am. J. Sci. PD MAY PY 1994 VL 294 IS 5 BP 621 EP 640 PG 20 WC Geosciences, Multidisciplinary SC Geology GA NJ940 UT WOS:A1994NJ94000003 ER PT J AU JOYCE, DB VOIGT, DE AF JOYCE, DB VOIGT, DE TI A PHASE-EQUILIBRIUM STUDY IN THE SYSTEM KALSI3O8-NAALSI3O8-SIO2-AL2SIO5-H2O AND PETROGENETIC IMPLICATIONS SO AMERICAN MINERALOGIST LA English DT Article ID QZ-AB-OR; ANDALUSITE; ALUMINUM AB The effect of saturating haplogranitic melts with sillimanite at 2 kbar was examined by determining near-eutectic or near-minimum melt phase relations in the sillimanite-free and sillimanite-saturated haplogranite systems. Three series of compositions were studied with Ab/(Ab + Sa) ratios of 0, 0.545, and 1.0. The solubilities of sillimanite in these melts were nearly indistinguishable from each other (3.5 +/- 0.5, 3.7 +/- 0.3, and 3.7 +/- 0.5 wt%, respectively). Under sillimanite-saturated conditions, the eutectic or minimum-melt temperatures were lowered by 15-29-degrees-C, and the melt compositions were shifted to more quartz-rich compositions by 1.5-2.5 wt%. At 2 kbar, the temperatures and compositions (on an anhydrous, sillimanite-free basis) of the four- and five-phase points are [GRAPHICS] The solubility of sillimanite in these melts was found to be insensitive to P and T over the range studied, 2.0 and 6.0 kbar, 680-900-degrees-C, but preliminary experiments indicate that it is increased by the presence of mafic components. This lowering of the minimum-melt temperature may explain the observation of apparently primary magmatic andalusite in some granitic rocks. C1 PENN STATE UNIV,DEPT GEOSCI,UNIV PK,PA 16802. RP JOYCE, DB (reprint author), OAK RIDGE NATL LAB,DIV CHEM,POB 2008,MS 6110,OAK RIDGE,TN 37831, USA. NR 26 TC 16 Z9 16 U1 0 U2 0 PU MINERALOGICAL SOC AMER PI WASHINGTON PA 1130 17TH ST NW SUITE 330, WASHINGTON, DC 20036 SN 0003-004X J9 AM MINERAL JI Am. Miner. PD MAY-JUN PY 1994 VL 79 IS 5-6 BP 504 EP 512 PG 9 WC Geochemistry & Geophysics; Mineralogy SC Geochemistry & Geophysics; Mineralogy GA NR968 UT WOS:A1994NR96800011 ER PT J AU TIETJEN, G AF TIETJEN, G TI RECURSIVE SCHEMES FOR CALCULATING CUMULATIVE BINOMIAL AND POISSON PROBABILITIES SO AMERICAN STATISTICIAN LA English DT Article DE BINOMIAL DISTRIBUTION; CHI-SQUARE DISTRIBUTION; POISSON DISTRIBUTION; STATISTICAL COMPUTING AB Cumulative probabilities for the binomial, Poisson and chi-square distributions can be formidable to calculate because of the size of the components. A simple code is given that utilizes the ratio of successive terms and thus avoids most of the computational difficulties. RP TIETJEN, G (reprint author), LOS ALAMOS NATL LAB,STAT GRP,LOS ALAMOS,NM 87545, USA. NR 5 TC 2 Z9 2 U1 0 U2 0 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0003-1305 J9 AM STAT JI Am. Stat. PD MAY PY 1994 VL 48 IS 2 BP 136 EP 137 DI 10.2307/2684267 PG 2 WC Statistics & Probability SC Mathematics GA NU499 UT WOS:A1994NU49900026 ER PT J AU UENO, K YEUNG, ES AF UENO, K YEUNG, ES TI SIMULTANEOUS MONITORING OF DNA FRAGMENTS SEPARATED BY ELECTROPHORESIS IN A MULTIPLEXED ARRAY OF 100 CAPILLARIES SO ANALYTICAL CHEMISTRY LA English DT Article ID LASER-INDUCED FLUORESCENCE; GEL-ELECTROPHORESIS; ZONE ELECTROPHORESIS AB Various excitation schemes for distributing a laser beam to a large number of capillaries in an array are evaluated. This led to the construction of a multiplexed system for monitoring the electrophoresis of DNA fragments in 100 capillaries. The laser excited fluorescence signals from each capillary are simultaneously recorded at the rate of 0.6 frame/s by a CCD camera. The reconstructed electropherograms show excellent reproducibility and minimal cross-talk. The system provides for two simultaneous excitation wavelengths so that it can be adapted for two-color, two-intensity DNA sequencing based on the commercial four-dye chemistry. Only 20 mW per laser line was employed. Further development of this system to accommodate up to 4096 independent sequencing channels at a time is discussed. C1 US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 26 TC 200 Z9 205 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAY 1 PY 1994 VL 66 IS 9 BP 1424 EP 1431 DI 10.1021/ac00081a010 PG 8 WC Chemistry, Analytical SC Chemistry GA NJ066 UT WOS:A1994NJ06600012 ER PT J AU DEBUSK, RF MILLER, NH SUPERKO, HR DENNIS, CA THOMAS, RJ LEW, HT BERGER, WE HELLER, RS ROMPF, J GEE, D KRAEMER, HC BANDURA, A GHANDOUR, G CLARK, M SHAH, RV FISHER, L TAYLOR, CB AF DEBUSK, RF MILLER, NH SUPERKO, HR DENNIS, CA THOMAS, RJ LEW, HT BERGER, WE HELLER, RS ROMPF, J GEE, D KRAEMER, HC BANDURA, A GHANDOUR, G CLARK, M SHAH, RV FISHER, L TAYLOR, CB TI A CASE-MANAGEMENT SYSTEM FOR CORONARY RISK FACTOR MODIFICATION AFTER ACUTE MYOCARDIAL-INFARCTION SO ANNALS OF INTERNAL MEDICINE LA English DT Article DE MYOCARDIAL INFARCTION; RISK FACTORS; SMOKING CESSATION; HYPERLIPIDEMIA; EXERCISE THERAPY ID ARTERY DISEASE; HEART-DISEASE; FOLLOW-UP; CHOLESTEROL; EXERCISE; THERAPY; INTERVENTION; MEN; HYPERCHOLESTEROLEMIA; PROGRESSION AB Objective: To evaluate the efficacy of a physician-directed, nurse-managed, home-based case-management system for coronary risk factor modification. Design: Randomized clinical trial in which patients received a special intervention (n = 293) or usual medical Care (n = 292) during the first year after acute myocardial infarction. n Setting: 5 Kaiser Permanents Medical Centers in the San Francisco Bay area. Patients: 585 men and women aged 70 years or younger who were hospitalized for acute myocardial infarction. Intervention: In the hospital, specially trained nurses initiated interventions for smoking cessation, exercise training, and diet-drug therapy for hyperlipidemia. Intervention after discharge was implemented primarily by telephone and mail contact with patients in their homes. All medically eligible patients received exercise training; all smokers received the smoking cessation intervention; and all patients received dietary counseling and, if needed, lipid-lowering drug therapy. Outcome: Smoking prevalence and plasma low-density lipoprotein cholesterol (LDL) concentrations were measured 2 months alter infarction, and functional capacity was measured 6 months after infarction. Results: In the special intervention and usual care groups, the cotinine-confirmed smoking cessation rates were 70% and 53% (P = 0.03), plasma LDL cholesterol levels were 2.77 +/- 0.69 mmol/L and 3.41 +/- 0.90 mmol/L (107 +/- 30 mg/dL and 132 +/- 30 mg/dL) (P = 0.001), and functional capacities were 9.3 +/- 2.4 METS and 8.4 +/- 2.5 METS (P = 0.001), respectively. Conclusion: In a large health maintenance organization, a case-management system was considerably more effective than usual medical care for modification of coronary risk factors after myocardial infarction. C1 STANFORD UNIV,SCH MED,STANFORD,CA. KAISER PERMANENTE MED CARE PROGRAM,SANTA CLARA,CA. KAISER PERMANENTE MED CARE PROGRAM,REDWOOD CITY,CA. KAISER PERMANENTE MED CARE PROGRAM,HAYWARD,CA. KAISER PERMANENTE MED CARE PROGRAM,SAN JOSE,CA. KAISER PERMANENTE MED CARE PROGRAM,WALNUT CREEK,CA. DEBORAH HEART & LUNG INST,BROWNS MILLS,NJ. NORTHWESTERN UNIV,SCH MED,CHICAGO,IL. LAWRENCE BERKELEY LAB,BERKELEY,CA. FU NHLBI NIH HHS [HL38874] NR 34 TC 481 Z9 485 U1 0 U2 9 PU AMER COLL PHYSICIANS PI PHILADELPHIA PA INDEPENDENCE MALL WEST 6TH AND RACE ST, PHILADELPHIA, PA 19106-1572 SN 0003-4819 J9 ANN INTERN MED JI Ann. Intern. Med. PD MAY 1 PY 1994 VL 120 IS 9 BP 721 EP 729 PG 9 WC Medicine, General & Internal SC General & Internal Medicine GA NH251 UT WOS:A1994NH25100001 PM 8147544 ER PT J AU DIFONZO, S JARK, W SCHAFERS, F PETERSEN, H GAUPP, A UNDERWOOD, JH AF DIFONZO, S JARK, W SCHAFERS, F PETERSEN, H GAUPP, A UNDERWOOD, JH TI PHASE-RETARDATION AND FULL-POLARIZATION ANALYSIS OF SOFT-X-RAY SYNCHROTRON-RADIATION CLOSE TO THE CARBON-K EDGE BY USE OF A MULTILAYER TRANSMISSION FILTER SO APPLIED OPTICS LA English DT Article DE POLARIZATION; PHASE RETARDATION; MULTILAYER; SYNCHROTRON RADIATION ID POLARIMETER; GENERATION; BESSY AB We have produced a multilayer transmission filter with 100 periods of Cr/C to achieve a significant phase retardation while maintaining good transmission for photon energies just below the carbon K edge. This device was installed into a polarimeter behind the SX700/3 monochromator at the Berlin synchrotron radiation laboratory, BESSY. The phase-retardation properties were observed as theoretically predicted. Agreement between experiment and calculation could be obtained by introduction of a rather small interface roughness in the simulation code (sigma = 0.65 nm rms). An observed phase retardation of 5-degrees was sufficient to permit, for the first time we believe, a complete and unambiguous polarization analysis of soft-x-ray synchrotron radiation (265-eV photon energy) with primary standards. C1 BERLIN SYNCHROTRON RADIAT LAB BESSY, D-14195 BERLIN, GERMANY. LAWRENCE BERKELEY LAB, CTR XRAY OPT, BERKELEY, CA 94720 USA. RP DIFONZO, S (reprint author), SINCROTRONE TRIESTE, PADRICIANO 99, I-34012 TRIESTE, ITALY. NR 28 TC 28 Z9 28 U1 1 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD MAY 1 PY 1994 VL 33 IS 13 BP 2624 EP 2632 PG 9 WC Optics SC Optics GA NJ771 UT WOS:A1994NJ77100027 ER PT J AU CHRISTY, AA NODLAND, E BURNHAM, AK KVALHEIM, OM DAHL, B AF CHRISTY, AA NODLAND, E BURNHAM, AK KVALHEIM, OM DAHL, B TI DETERMINATION OF KINETIC-PARAMETERS FOR THE DEHYDRATION OF CALCIUM-OXALATE MONOHYDRATE BY DIFFUSE-REFLECTANCE FT-IR SPECTROSCOPY SO APPLIED SPECTROSCOPY LA English DT Article DE DIFFUSE REFLECTANCE, THERMAL DECOMPOSITION; KINETIC PARAMETERS; CALCIUM OXALATE MONOHYDRATE ID THERMAL-DECOMPOSITION AB Variable-temperature diffuse reflectance infrared spectroscopy was used to study the reaction kinetics of the dehydration of calcium oxalate monohydrate. The kinetic analysis of the dehydration process indicates that there are two reactions taking place, as well as the presence of two different equimole water molecular environments in the crystal structure of calcium oxalate monohydrate. Partial least-squares calibration of the dehydration profiles was carried out to identify the evolution sequence of the two different types of water molecules in the crystal structure of calcium oxalate monohydrate. The results indicate that the water molecules in the crystal structure which are responsible for the stretching absorptions at 3428 and 3336 cm-1 are eliminated first at a higher rate, during the first part of the reaction, and the others responsible for the absorptions at 3486 and 3058 cm-1 are eliminated at a later stage. The unexpected and unidentified band arising from bending modes of one of the types of water molecules is shown to arise from the same water molecules that are responsible for the stretching absorptions at 3486 and 3058 cm-1. Kinetic parameters were determined for the dehydration step, and the overall activation energy calculated for the dehydration step is in agreement with values reported in the literature. However, the clear presence of two distinct reactions invalidates all previous determinations of reaction order. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551. RP CHRISTY, AA (reprint author), UNIV BERGEN,DEPT CHEM,N-5007 BERGEN,NORWAY. NR 24 TC 19 Z9 20 U1 1 U2 5 PU SOC APPLIED SPECTROSCOPY PI FREDERICK PA PO BOX 1438, FREDERICK, MD 21701 SN 0003-7028 J9 APPL SPECTROSC JI Appl. Spectrosc. PD MAY PY 1994 VL 48 IS 5 BP 561 EP 568 DI 10.1366/0003702944924916 PG 8 WC Instruments & Instrumentation; Spectroscopy SC Instruments & Instrumentation; Spectroscopy GA NP999 UT WOS:A1994NP99900007 ER PT J AU PARANTHAMAN, M THOMPSON, JR SUN, YR BRYNESTAD, J KROEGER, DM AF PARANTHAMAN, M THOMPSON, JR SUN, YR BRYNESTAD, J KROEGER, DM TI EVIDENCE FOR PHASE-STABILITY AND WEAK LINKS IN POLYCRYSTALLINE HGBA2CUO4+DELTA SO APPLIED SUPERCONDUCTIVITY LA English DT Article ID CU-O SYSTEM; CURRENT-DENSITY; IRREVERSIBILITY LINE; COLUMNAR DEFECTS; FLUX-CREEP; SUPERCONDUCTIVITY; CRYSTALS; IRRADIATION AB Polycrystalline HgBa2CuO4 + delta (hereafter denoted as Hg-1201) superconductors were prepared by solid state reaction of stoichiometric quantities of HgO and Ba2CuO3 precursors in an evacuated quartz tube. The ''as-synthesized'' Hg-1201 samples had a T(c) of 95 K, as defined by the onset of diamagnetism. The crystal symmetry was tetragonal with lattice parameters, a = 3.876(2) angstrom, and c = 9.515(3) angstrom, similar to reported values. These results were highly reproducible with several batches. Finely ground Hg-1201 powders were stable upon overnight exposure to ambient air; long-term exposure (approximately 10 days) of the powders led to surface deterioration and minor changes in the X-ray pattern, with no observed change in the bulk T(c). Low field magnetization studies showed complete shielding. A Meissner signal approximately 30% of (-1/4 pi), and clear evidence for weak coupling between the randomly oriented superconducting grains. In large magnetic fields, the hysteresis of the magnetization (proportional to the intragrain current density, assuming a Bean model) decreased rapidly with applied field and temperature. These features and direct studies of the time dependent magnetization give unambiguous evidence for substantial flux creep effects. C1 UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,DIV MET & CERAM,OAK RIDGE,TN 37831. RP PARANTHAMAN, M (reprint author), OAK RIDGE NATL LAB,DIV CHEM,POB 2008,OAK RIDGE,TN 37831, USA. RI Paranthaman, Mariappan/N-3866-2015 OI Paranthaman, Mariappan/0000-0003-3009-8531 NR 21 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0964-1807 J9 APPL SUPERCOND JI Appl. Supercond. PD MAY PY 1994 VL 2 IS 5 BP 359 EP 365 DI 10.1016/0964-1807(94)90021-3 PG 7 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA PH677 UT WOS:A1994PH67700005 ER PT J AU PETERSON, D FREIMAN, SW AF PETERSON, D FREIMAN, SW TI SUMMARY OF NIST DOE WORKSHOP - PHASE-DIAGRAMS FOR HIGH T(C) SUPERCONDUCTORS SO APPLIED SUPERCONDUCTIVITY LA English DT Article ID CRYSTAL-CHEMISTRY; EQUILIBRIA; YBA2CU3O6+X; SYSTEMS AB On June 2-4, 1993, a workshop on Phase Diagrams for High T(c) Superconductors was held at the Picacho Plaza Hotel Hotel in Santa Fe, New Mexico. The purpose of this workshop was to allow workers in this field to present the most up-to-date picture of phase diagrams and related data in chemical systems important for the processing and application of high T(c) superconductors. In addition to phase equilibria information, a number of attendees presented recently obtained data on the newly discovered Hg containing superconductors which have reported T(c)'s as high as 133 K. This summary is divided into sections, each section dealing with a particular superconducting system. The final section consists of suggested priorities for future phase equilibria studies reached by consensus of the attendees. C1 NATL INST STAND & TECHNOL,DIV CERAM,GAITHERSBURG,MD 20899. RP PETERSON, D (reprint author), LOS ALAMOS NATL LAB,CTR SUPERCONDUCT TECHNOL,LOS ALAMOS,NM 87545, USA. NR 10 TC 0 Z9 0 U1 1 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0964-1807 J9 APPL SUPERCOND JI Appl. Supercond. PD MAY PY 1994 VL 2 IS 5 BP 367 EP 372 DI 10.1016/0964-1807(94)90022-1 PG 6 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA PH677 UT WOS:A1994PH67700006 ER PT J AU ROSENBERG, RA FRIGO, SP SIMONS, JK AF ROSENBERG, RA FRIGO, SP SIMONS, JK TI SYNCHROTRON-RADIATION-INDUCED REACTIONS ON SURFACES - MECHANISMS AND APPLICATIONS SO APPLIED SURFACE SCIENCE LA English DT Article ID CHEMICAL-VAPOR-DEPOSITION; PHOTON-STIMULATED DESORPTION; SI EPITAXIAL-GROWTH; MOLECULAR-BEAM SYSTEM; BORON-CARBIDE FILMS; LOW-TEMPERATURE; ROOM-TEMPERATURE; PHOTOSTIMULATED EVAPORATION; ASSISTED NITRIDATION; SILICON SURFACE AB In this paper we tabulate recent research that delves into the application of synchrotron radiation for inducing surface chemical reactions. We then present results from recent experiments designed to test whether surface photochemical reactions can be brought about by direct core-level excitation of the adsorbate, as opposed to an indirect mechanism where photoabsorption by bulk atoms produces secondary electrons that cause the reaction. Experiments were performed on SiF4 adsorbed on Ge(100) at 30 K. It was found that direct excitation of Si 2p core levels causes the reaction to occur. Finally we show the application of X-ray dependent surface photochemistry in two systems of technological relevance. The first is adamantane (C10H16) adsorbed on Si(111) at 85 K. X-rays with energies greater than the CK edge (284 eV) cause significant bond breaking and the formation of SiC. Lower energy X-rays appear to create adamantyl radicals which bond strongly with the substrate and are stable to 625 K. The second is Teflon where irradiation with photons with energies lower than 12 eV induces the desorption of relatively large fluorocarbon fragments, as compared to photolysis with photons of energies greater than 22 eV (C2s excitation). C1 UNIV WISCONSIN, DEPT PHYS, MADISON, WI 53706 USA. UNIV WISCONSIN, DEPT CHEM, MADISON, WI 53706 USA. UNIV WISCONSIN, CTR SYNCHROTRON RADIAT, MADISON, WI 53706 USA. RP ROSENBERG, RA (reprint author), ARGONNE NATL LAB, ADV PHOTON SOURCE, 9700 S CASS AVE, ARGONNE, IL 60439 USA. RI Rosenberg, Richard/K-3442-2012 NR 83 TC 31 Z9 31 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD MAY PY 1994 VL 79-80 BP 47 EP 56 DI 10.1016/0169-4332(94)90386-7 PG 10 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA NR963 UT WOS:A1994NR96300007 ER PT J AU NIWANO, M MIYAMOTO, N SIMONS, JK FRIGO, SP ROSENBERG, RA AF NIWANO, M MIYAMOTO, N SIMONS, JK FRIGO, SP ROSENBERG, RA TI PHOTOEMISSION-STUDY OF SYNCHROTRON-RADIATION-INDUCED REACTIONS OF TEOS ADSORBED ON SILICON SURFACE SO APPLIED SURFACE SCIENCE LA English DT Article ID CHEMICAL VAPOR-DEPOSITION; SIO2/SI INTERFACE; FILM; BORON; OXIDE AB We have investigated the synchrotron radiation (SR) induced chemical reactions of tetraethoxysilane Si(OC2H5)4 (TEOS) adsorbed on Si, using photoemission spectroscopy. TEOS adsorbs on the Si surface with its molecular structure intact, at least below room temperature. SR in the vacuum ultraviolet region decomposes the TEOS molecules adsorbed on Si to form a silicon oxide like film, but some carbon remains in the film. Results of irradiation experiments on condensed layers of TEOS and water adsorbed on Si at 85 K indicate that the addition of water enhances the removal of carbon contamination in the oxide film. C1 UNIV WISCONSIN, CTR SYNCHROTRON RADIAT, STOUGHTON, WI 53589 USA. ARGONNE NATL LAB, ADV PHOTON SOURCE, ARGONNE, IL 60439 USA. RP NIWANO, M (reprint author), TOHOKU UNIV, ELECT COMMUN RES INST, SENDAI, MIYAGI 980, JAPAN. RI Rosenberg, Richard/K-3442-2012 NR 20 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-4332 J9 APPL SURF SCI JI Appl. Surf. Sci. PD MAY PY 1994 VL 79-80 BP 403 EP 408 DI 10.1016/0169-4332(94)90445-6 PG 6 WC Chemistry, Physical; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Chemistry; Materials Science; Physics GA NR963 UT WOS:A1994NR96300066 ER PT J AU AUER, LH PALETOU, F AF AUER, LH PALETOU, F TI 2-DIMENSIONAL RADIATIVE-TRANSFER WITH PARTIAL FREQUENCY REDISTRIBUTION .1. GENERAL-METHOD SO ASTRONOMY & ASTROPHYSICS LA English DT Article DE RADIATIVE TRANSFER; METHODS, NUMERICAL ID QUIESCENT PROMINENCES AB We present a new method for the solution of non-LTE scattering problems in two dimensions. It is based on Accelerated Lambda Iteration and an improved short characteristic method. It is more than an order of magnitude faster than a direct approach for Complete Redistribution. We, further, have extended the method to the solution of Partial Redistribution problems. The computational cost of treating PRD with the new method is only a small factor larger than CRD. Results with the new iterative approach are in complete agreement with previously published results. C1 UNIV PARIS 11, INST ASTROPHYS SPATIALE, F-91405 ORSAY, FRANCE. RP LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. NR 17 TC 82 Z9 82 U1 0 U2 0 PU EDP SCIENCES S A PI LES ULIS CEDEX A PA 17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE SN 1432-0746 J9 ASTRON ASTROPHYS JI Astron. Astrophys. PD MAY PY 1994 VL 285 IS 2 BP 675 EP 686 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NM403 UT WOS:A1994NM40300042 ER PT J AU HAWLEY, SL FISHER, GH AF HAWLEY, SL FISHER, GH TI SOLAR-FLARE MODEL ATMOSPHERES SO ASTROPHYSICAL JOURNAL LA English DT Article DE RADIATIVE TRANSFER; SUN, ATMOSPHERE; SUN, CHROMOSPHERE; SUN, CORONA; SUN, FLARES ID H-ALPHA; HYDROGEN LINES; THERMAL MODELS; EVAPORATION; TEMPERATURE; ELECTRONS; DYNAMICS; BALANCE; REGION; PLASMA AB Solar flare model atmospheres computed under the assumption of energetic equilibrium in the chromosphere are presented. The models use a static, one-dimensional plane-parallel geometry and are designed within a physically self-consistent coronal loop. Assumed flare heating mechanisms include collisions from a flux of nonthermal electrons and X-ray heating of the chromosphere by the corona. The heating by energetic electrons accounts explicitly for variations of the ionized fraction with depth in the atmosphere. X-ray heating of the chromosphere by the corona incorporates a flare loop geometry by approximating distant portions of the loop with a series of point sources, while treating the loop leg closest to the chromospheric footpoint in the plane-parallel approximation. Coronal flare heating leads to increased heat conduction, chromospheric evaporation and subsequent changes in coronal pressure; these effects are included self-consistently in the models. Cooling in the chromosphere is computed in detail for the important optically thick H I, Ca II and Mg II transitions using the non-LTE prescription in the program MULTI. Hydrogen ionization rates from X-ray photoionization and collisional ionization by nonthermal electrons are included explicitly in the rate equations. The models are computed in the ''impulsive'' and ''equilibrium'' limits, and in a set of intermediate ''evolving'' states. The impulsive atmospheres have the density distribution frozen in the pre-flare configuration, while the equilibrium models assume the entire atmosphere is in hydrostatic and energetic equilibrium. The evolving atmospheres represent intermediate stages where hydrostatic equilibrium has been established in the chromosphere and corona, but the corona is not yet in energetic equilibrium with the flare heating source. Thus, for example, chromospheric evaporation is still in the process of occurring. We have computed the chromospheric radiation that results from a range of coronal heating rates, with particular emphasis on the widely observed diagnostic Halpha. Our principal results are the following: 1. Only in models with low coronal pressure (i.e., in models where very little evaporation has occurred) does the nonthermal electron flux provide significant heating in the chromosphere. 2. After evaporation has occurred and the coronal pressure is high, the dominant source of chromospheric heating is the X-ray irradiation from the hot corona. However, this reprocessed heat source never exceeds approximately 6% of the original flare energy flux deposited in the corona by the beam. 3. In order to obtain the broad, intense Halpha profiles that are actually observed in flares, there must be either (a) a condition of low coronal pressure in the overlying loop; or (b) heating at the top of the chromosphere from a source other than the beam and its products (X-rays, heat conduction). The reason is that only with a low-pressure corona is there enough chromospheric heating from the beam to raise enough column mass to temperatures of approximately 10(4) K necessary to produce copious Halpha. 4. The depth of the Halpha central reversal was correlated with the incident coronal beam flux F-20 in our models in the sense that models with large beam flux have profiles with smaller central reversal. 5. Losses from ions other than those we treat in detail play a very important, and in many cases dominant, role in the cooling of the chromosphere. Further models should include the radiation backwarming effects of these losses. 6. The power-law dependence of the ratio F(Halpha)/F-20 on the beam flux F-20, which has been empirically determined, was reproduced in some of our models. However, we find that a more physically meaningful parameter during the evolution of a single loop is the pressure, P, since the chromospheric heating after evaporation has occurred depends primarily on the coronal pressure (or alternatively the conductive flux or coronal column depth) and not on the beam flux. Our conclusion is that the Halpha fluxes and profiles actually observed in flares can only be produced under conditions of a low-pressure corona with strong beam heating. Therefore we suggest that Halpha in flares is produced primarily at the footpoints of newly heated loops where significant evaporation has not yet occurred. As a single loop evolves in time, no matter how strong the heating rate may become, the Halpha flux will diminish as the corona becomes denser and hence more effective at stopping the beam. This prediction leads to several observable consequences regarding the spatial and temporal signatures of the X-ray and Halpha radiation during flares. C1 LAWRENCE LIVERMORE NATL LAB, INST GEOPHYS & PLANETARY PHYS, LIVERMORE, CA 94551 USA. UNIV CALIF BERKELEY, SPACE SCI LAB, BERKELEY, CA 94720 USA. RI Fisher, George/G-1380-2015 OI Fisher, George/0000-0002-6912-5704 NR 38 TC 46 Z9 46 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 1994 VL 426 IS 1 BP 387 EP 403 DI 10.1086/174075 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NG668 UT WOS:A1994NG66800042 ER PT J AU ALEXANDREAS, DE ALLEN, GE BERLEY, D BILLER, S BURMAN, RL CAVALLISFORZA, M CHANG, CY CHEN, ML CHUMNEY, P COYNE, D DION, C DION, GM DOREAN, D ELLSWORTH, RW GOODMAN, JA HAINES, TJ HARMON, M HOFFMAN, CM KELLEY, L KLEIN, S NAGLE, DE SCHALLER, SC SCHMIDT, DM SCHNEE, R SHOUP, A SINNIS, C STARK, MJ WEEKS, DD WILLIAMS, DA WU, JP YANG, T YODH, GB ZHANG, W AF ALEXANDREAS, DE ALLEN, GE BERLEY, D BILLER, S BURMAN, RL CAVALLISFORZA, M CHANG, CY CHEN, ML CHUMNEY, P COYNE, D DION, C DION, GM DOREAN, D ELLSWORTH, RW GOODMAN, JA HAINES, TJ HARMON, M HOFFMAN, CM KELLEY, L KLEIN, S NAGLE, DE SCHALLER, SC SCHMIDT, DM SCHNEE, R SHOUP, A SINNIS, C STARK, MJ WEEKS, DD WILLIAMS, DA WU, JP YANG, T YODH, GB ZHANG, W TI SEARCH FOR ULTRA-HIGH-ENERGY RADIATION FROM GAMMA-RAY BURSTS SO ASTROPHYSICAL JOURNAL LA English DT Article DE GAMMA-RAYS, BURSTS; GAMMA-RAYS, OBSERVATIONS AB A recent class of models suggests that some gamma-ray bursters may produce ultra-high-energy (greater than or similar 100 TeV) photons. Using data from the CYGNUS array, we have searched for evidence of emission of ultra-high-energy radiation coincident with gamma-ray bursts observed either by the third Interplanetary Network of satellites or by the BATSE instrument on the Compton Gamma-Ray Observatory. No statistically significant excess was found for six bursts whose locations were accurately determined by the Network, or for any point in the sky within 2 sigma of the BATSE location coordinates of 52 additional bursts. Flux upper limits depend greatly on the zenith angles of the bursts, but typical limits above 100 TeV are approximately 4 x 10(-10) cm-2 s-1. The flux upper limits for three of the bursts imply that the observed spectrum softens between 2 MeV and approximately 100 TeV. If the production spectrum does not soften between these energies, the bursts must have a cosmological origin. C1 UNIV CALIF IRVINE,IRVINE,CA 92717. UNIV MARYLAND,COLL PK,MD 20742. NATL SCI FDN,WASHINGTON,DC 20550. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. UNIV CALIF SANTA CRUZ,SANTA CRUZ,CA 95064. GEORGE MASON UNIV,FAIRFAX,VA 22030. UNIV CALIF RIVERSIDE,RIVERSIDE,CA 92521. RI Cavalli-Sforza, Matteo/H-7102-2015 NR 27 TC 15 Z9 15 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAY 1 PY 1994 VL 426 IS 1 BP L1 EP L3 DI 10.1086/187325 PN 2 PG 3 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NG669 UT WOS:A1994NG66900001 ER PT J AU LEE, IY PARK, HM AF LEE, IY PARK, HM TI COMPARISON OF MICROPHYSICS PARAMETERIZATIONS IN A 3-DIMENSIONAL DYNAMIC CLOUD MODEL SO ATMOSPHERIC ENVIRONMENT LA English DT Article DE CLOUD MICROPHYSICS PARAMETERIZATIONS; HYDROMETEOR MIXING RATIOS; CLOUD DYNAMICS ID NUMERICAL-SIMULATION; BOUNDARY; PRECIPITATION; CONDENSATION; GROWTH; RATES AB A three-dimensional, time-dependent flow model developed to simulate dynamics and cloud microphysics for warm-cloud processes is used to compare the moisture fields simulated with different cloud microphysics parameterizations. Our parameterizations are based on detailed simulations of the physics of aerosol, clouds, and precipitation. The moisture content in the system is differentiated into water vapor, cloud water, and rain water. Advection and diffusion terms for momentum, potential temperature, and mixing ratios of water vapor and cloud water are calculated by using finite-volume methods, while rain water mixing ratio fields are calculated by a Lagrangian method. The model simulations are examined through sensitivity analysis, interpreted in terms of the physical processes occurring, and are compared with simulations using parameterizations from the literature. Calculated precipitation totals are shown to vary by 10-30% among simulations with alternate parameterizations. C1 SOGANG UNIV,DEPT CHEM ENGN,SEOUL,SOUTH KOREA. RP LEE, IY (reprint author), ARGONNE NATL LAB,DIV ENVIRONM RES,ARGONNE,IL 60439, USA. NR 32 TC 4 Z9 4 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 1352-2310 J9 ATMOS ENVIRON JI Atmos. Environ. PD MAY PY 1994 VL 28 IS 9 BP 1615 EP 1625 DI 10.1016/1352-2310(94)90307-7 PG 11 WC Environmental Sciences; Meteorology & Atmospheric Sciences SC Environmental Sciences & Ecology; Meteorology & Atmospheric Sciences GA NR413 UT WOS:A1994NR41300005 ER PT J AU SAMPSON, DH ZHANG, HL FONTES, CJ AF SAMPSON, DH ZHANG, HL FONTES, CJ TI A REVIEW OF AVAILABLE COLLISION STRENGTH DATA FOR THE BORON ISOELECTRONIC SEQUENCE (Z = 5 TO 28) SO ATOMIC DATA AND NUCLEAR DATA TABLES LA English DT Review ID ELECTRON-IMPACT EXCITATION; RATE COEFFICIENTS; N-III; O-IV; DENSITY DIAGNOSTICS; ULTRAVIOLET LINES; CROSS-SECTIONS; FINE-STRUCTURE; ATOMIC DATA; C-II AB A review is given of the available data on collision strengths and effective, or Maxwellian-averaged, collision strengths for neutral boron and all boron-like ions up to and including boron-like nickel. When sufficient collision strength data are available for the determination of two or more sets of effective collision strengths gamma for the same ion by different authors, comparison graphs of gamma versus the logarithm of the electron temperature T(K) are given. (C) 1994 Academic Press, Inc. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP SAMPSON, DH (reprint author), PENN STATE UNIV,DEPT ASTRON & ASTROPHYS,UNIVERSITY PK,PA 16802, USA. NR 42 TC 10 Z9 10 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0092-640X J9 ATOM DATA NUCL DATA JI Atom. Data Nucl. Data Tables PD MAY-JUL PY 1994 VL 57 IS 1-2 BP 97 EP 124 DI 10.1006/adnd.1994.1013 PG 28 WC Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Physics GA NX988 UT WOS:A1994NX98800006 ER PT J AU SAVIKHIN, S VANAMERONGEN, H KWA, SLS VANGRONDELLE, R STRUVE, WR AF SAVIKHIN, S VANAMERONGEN, H KWA, SLS VANGRONDELLE, R STRUVE, WR TI LOW-TEMPERATURE ENERGY-TRANSFER IN LHC-II TRIMERS FROM THE CHL-A/B LIGHT-HARVESTING ANTENNA OF PHOTOSYSTEM-II SO BIOPHYSICAL JOURNAL LA English DT Article ID PROTEIN COMPLEX; ELECTRON CRYSTALLOGRAPHY; PARTICLES; MEMBRANE; SPINACH AB Temperature dependence in electronic energy transfer steps within light-harvesting antenna trimers from photosystem II was investigated by studying Chl a pump-probe anisotropy decays at several wavelengths from 675 to 682 nm. The anisotropy lifetime is markedly sensitive to temperature at the longest wavelengths (680-682 nm), increasing by factors of 5 to 6 as the trimers are cooled from room temperature to 13 K. The temperature dependence is muted at 677 and 675 nm. This behavior is modeled using simulations of temperature-broadened Chl a absorption and fluorescence spectra in spectral overlap calculations of Forster energy transfer rates. In this model, the 680 nm anisotropy decays are dominated by uphill energy transfers from 680 nm Chl a pigments at the red edge of the LHC-II spectrum; the 675 nm anisotropy decays reflect a statistical average of uphill and downhill energy transfers from 676-nm pigments. The measured temperature dependence is consistent with essentially uncorrelated inhomogeneous broadening of donor and acceptor Chl a pigments. C1 IOWA STATE UNIV SCI & TECHNOL, US DOE, AMES LAB, AMES, IA 50011 USA. FREE UNIV AMSTERDAM, DEPT PHYS & ASTRON, AMSTERDAM, NETHERLANDS. RI van Amerongen, Herbert/J-9483-2016 OI van Amerongen, Herbert/0000-0002-9783-2895 NR 24 TC 43 Z9 44 U1 0 U2 7 PU CELL PRESS PI CAMBRIDGE PA 600 TECHNOLOGY SQUARE, 5TH FLOOR, CAMBRIDGE, MA 02139 USA SN 0006-3495 EI 1542-0086 J9 BIOPHYS J JI Biophys. J. PD MAY PY 1994 VL 66 IS 5 BP 1597 EP 1603 PG 7 WC Biophysics SC Biophysics GA NG923 UT WOS:A1994NG92300036 PM 8061208 ER PT J AU KNOWLES, DW CHASIS, JA EVANS, EA MOHANDAS, N AF KNOWLES, DW CHASIS, JA EVANS, EA MOHANDAS, N TI COOPERATIVE ACTION BETWEEN BAND-3 AND GLYCOPHORIN-A IN HUMAN ERYTHROCYTES - IMMOBILIZATION OF BAND-3 INDUCED BY ANTIBODIES TO GLYCOPHORIN-A SO BIOPHYSICAL JOURNAL LA English DT Article ID RED-CELL MEMBRANE; MONOCLONAL-ANTIBODIES; HEREDITARY OVALOCYTOSIS; LATERAL MOBILITY; SIALOGLYCOPROTEINS; PROTEINS; SPECTRIN; DEFORMABILITY; ASSOCIATION; DIFFUSION AB The ability of transmembrane receptor proteins to change their association with the cytoskeleton in response to ligand binding seems to be a key mechanism of signal transduction across membranes. To investigate the molecular features of this mechanism we have used the red cell membrane as a model system to study signal transduction through the integral protein, glycophorin A. In these studies the lateral mobility of integral proteins was measured in situ by fluorescence recovery after photobleaching, and membrane rigidity was characterized by micropipette aspiration technique. We found that binding either a monoclonal antibody or its monovalent Fab to the exoplasmic domain of glycophorin A in normal red cells immobilized the receptor and rigidified the membrane. Further, immobilization and rigidification did not occur when antibodies were bound to Miltenberger V cells containing a mutant form of glycophorin A lacking the cytoplasmic domain. These results imply that the site of the immobilization/rigidification lies within the membrane skeletal structure, not in exofacial receptor crosslinking, and requires the extended cytoplasmic domain of normal glycophorin A. In addition, we found that glycophorin A immobilization and membrane skeletal rigidification were accompanied by immobilization of band 3 receptors. This unexpected result indicates a cooperative coupling between liganded glycophorin A, band 3, and the membrane skeleton. We speculate that cooperation of this type may represent a general mechanism for cytoskeletal linkage and transformation initiated by receptors with short cytoplasmic sequences, such as integrins. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV LIFE SCI,BERKELEY,CA 94720. UNIV BRITISH COLUMBIA,DEPT PHYS,VANCOUVER,BC,CANADA. UNIV BRITISH COLUMBIA,DEPT PATHOL,VANCOUVER,BC,CANADA. FU NHLBI NIH HHS [HL31579]; NIDDK NIH HHS [DK26263, DK32094] NR 44 TC 49 Z9 51 U1 0 U2 1 PU BIOPHYSICAL SOCIETY PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 SN 0006-3495 J9 BIOPHYS J JI Biophys. J. PD MAY PY 1994 VL 66 IS 5 BP 1726 EP 1732 PG 7 WC Biophysics SC Biophysics GA NG923 UT WOS:A1994NG92300049 PM 8061221 ER PT J AU LAI, CCA QIAN, W GLENN, SM AF LAI, CCA QIAN, W GLENN, SM TI DATA ASSIMILATION AND MODEL EVALUATION EXPERIMENT DATASETS SO BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY LA English DT Article ID GULF-STREAM; SYSTEM AB The Institute for Naval Oceanography, in cooperation with Naval Research Laboratories and universities, executed the Data Assimilation and Model Evaluation Experiment (DAMEE) for the Gulf Stream region during fiscal years 1991-1993. Enormous effort has gone into the preparation of several high-quality and consistent datasets tor model initialization and verification. This paper describes the preparation process, the temporal and spatial scopes, the contents, the structure, etc., of these datasets. The goal of DAMEE and the need of data for the four phases of experiment are briefly stated. The preparation of DAMEE datasets consisted of a series of processes: 1) collection of observational data; 2) analysis and interpretation; 3) interpolation using the Optimum Thermal Interpolation System package; 4) quality control and reanalysis; and 5) data archiving and software documentation. The data products from these processes included a time series of 3D fields of temperature and salinity, 2D fields of surface dynamic height and mixed-layer depth, analysis of the Gulf Stream and rings system, and bathythermograph profiles. To date, these are the most detailed and high-quality data for mesoscale ocean modeling, data assimilation, and forecasting research. Feedback from ocean modeling groups who tested this data was incorporated into its refinement. Suggestions tor DAMEE data usages include 1) ocean modeling and data assimilation studies, 2) diagnosis and theorectical studies, and 3) comparisons with locally detailed observations. C1 UNIV SO MISSISSIPPI,CTR OCEAN & ATMOSPHERE MODELING,BAY ST LOUIS,MS. RUTGERS STATE UNIV,INST MARINE & COASTAL SCI,NEW BRUNSWICK,NJ 08903. RP LAI, CCA (reprint author), LOS ALAMOS NATL LAB,DIV EARTH & ENVIRONM SCI,EES-S,MSD401,LOS ALAMOS,NM 87544, USA. NR 16 TC 7 Z9 7 U1 0 U2 0 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 SN 0003-0007 J9 B AM METEOROL SOC JI Bull. Amer. Meteorol. Soc. PD MAY PY 1994 VL 75 IS 5 BP 793 EP 809 DI 10.1175/1520-0477(1994)075<0793:DAAMEE>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA NP066 UT WOS:A1994NP06600003 ER PT J AU TINKER, DB ROMME, WH HARGROVE, WW GARDNER, RH TURNER, MG AF TINKER, DB ROMME, WH HARGROVE, WW GARDNER, RH TURNER, MG TI LANDSCAPE-SCALE HETEROGENEITY IN LODGEPOLE PINE SEROTINY SO CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE LA English DT Article ID CONTORTA; HISTORY; FIRE AB A 1992 study of serotiny in lodgepole pine (Pinus contorta Dougl. ex Loud.,var. latifolia Engelm.) in Yellowstone National Park asked four questions: (i) are there morphological characteristics that can be used to estimate pre-fire proportion of serotinous trees in forests that burned in 1988?; (ii) at what spatial scale does percent serotinous trees vary across the landscape?; (iii) which environmental factors are correlated with serotiny?; and (iv) what is the relationship between prefire serotiny and postfire lodgepole pine seedling density? We first sampled cone characteristics in serotinous and nonserotinous trees along four 2950-m transects in unburned forests, and examined burned trees nearby. Results indicated that asymmetrical cones and an acute angle of cone attachment to the branch were reliable indicators of serotiny even in burned trees. We then sampled nine patches of lodgepole pine forest that had burned in 1988, and varied in size from 1-3600 ha. We sampled serotiny at varying intervals along two perpendicular transects that crossed in the center of each patch. At each sample point, the 12 nearest canopy lodgepole pines were classified as serotinous or nonserotinous. We concluded that the percentage of serotinous trees is most variable at intermediate scales of 1-10 km, and is relatively homogeneous at both fine scales (<1 km) and at very broad scales (tens of kilometers). Percent serotiny was generally more variable and greater at low to middle elevations. Prefire density of serotinous trees was a more important predictor of postfire seedling density than aspect, slope, or soil type. These findings have important implications for landscape-level patterns in postfire regeneration of lodgepole pine. C1 FT LEWIS COLL,DEPT BIOL,DURANGO,CO 81301. OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831. RI Turner, Monica/B-2099-2010; Romme, William/C-7317-2016 NR 22 TC 52 Z9 54 U1 0 U2 15 PU NATL RESEARCH COUNCIL CANADA PI OTTAWA PA RESEARCH JOURNALS, MONTREAL RD, OTTAWA ON K1A 0R6, CANADA SN 0045-5067 J9 CAN J FOREST RES JI Can. J. For. Res.-Rev. Can. Rech. For. PD MAY PY 1994 VL 24 IS 5 BP 897 EP 903 DI 10.1139/x94-118 PG 7 WC Forestry SC Forestry GA NX676 UT WOS:A1994NX67600005 ER PT J AU Weber, BHF Stohr, H Siedlaczck, I Longmire, JL Deaven, LL Duncan, AMV Riess, O AF Weber, B. H. F. Stoehr, H. Siedlaczck, I. Longmire, J. L. Deaven, L. L. Duncan, A. M. V. Riess, O. TI Characterization of a cosmid library from flow-sorted chromosomes 11 SO CHROMOSOME RESEARCH LA English DT Article DE cosmid library; flow-sorted chromosomes; high-density screening; human chromosome 11 AB A cosmid library specific for human chromosome 11 has been constructed from flow-sorted chromosomes. The flow-purified chromosomes were prepared from the hamster/human hybrid line J1 which contains chromosome 11 as the only human chromosome. Individual clones were sampled in 187 microtitre plates, resulting in a total of 17 952 colonies. Hybridization analysis revealed that 83.7% of these clones were of human and 10.4% of hamster origin. The average insert size was estimated at 33.6 kb, and only 2.4% of insert fragments appear to be rearranged. This should result in 494 487 kb of cloned human DNA representing 3.5 chromosome 11 equivalents. We have prepared high-density nylon membranes of the arrayed library containing 1 536 single colonies per filter. We have demonstrated the usefulness of the library in the molecular genetic analysis of human chromosome 11 by testing for the presence of possibly polymorphic simple repeat motifs, by identifying cosmids that contain inserts from the telomeric ends of chromosome 11 and by assessing the potential of the library for rapid chromosome walking. C1 [Weber, B. H. F.; Stoehr, H.] Biozentrum, Inst Humangenet, D-97074 Wurzburg, Germany. [Siedlaczck, I.; Riess, O.] Ruhr Univ Bochum, Inst Genet, Bochum, Germany. [Longmire, J. L.; Deaven, L. L.] Univ Calif Los Alamos Natl Lab, Ctr Human Genome Studies, Los Alamos, NM 87545 USA. [Duncan, A. M. V.] Queens Univ, Dept Pathol, Kingston Gen Hosp, Kingston, ON K7L 3N6, Canada. RP Weber, BHF (reprint author), Biozentrum, Inst Humangenet, D-97074 Wurzburg, Germany. EM bweb@vax.rz.uni-wuerzburg.d400.de FU US Department of Energy; Deutsche Forschungsgemeinschaft (DFG) [We 1259/2-1]; Canadian Networks of Centres of Excellence Programme FX The excellent technical assistance of Susanne Kredtke and Linda L. Anderson is gratefully acknowledged. The chromosome 11 cosmid library was constructed at the Center for Human Genome Studies at the Los Alamos National Laboratory under the auspices of the US Department of Energy. This work was supported by the Deutsche Forschungsgemeinschaft (DFG) (We 1259/2-1) and by the Canadian Networks of Centres of Excellence Programme. NR 38 TC 6 Z9 6 U1 0 U2 0 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0967-3849 J9 CHROMOSOME RES JI Chromosome Res. PD MAY PY 1994 VL 2 IS 3 BP 201 EP 207 DI 10.1007/BF01553320 PG 7 WC Biochemistry & Molecular Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Genetics & Heredity GA V28DZ UT WOS:000208662800004 PM 8069463 ER PT J AU Winokur, ST Bengtsson, U Feddersen, J Mathews, KD Weiffenbach, B Bailey, H Markovich, RP Murray, JC Wasmuth, JJ Altherr, MR Schutte, BC AF Winokur, Sara T. Bengtsson, Ulla Feddersen, Julie Mathews, Kathy D. Weiffenbach, Barbara Bailey, Holly Markovich, Rachelle P. Murray, Jeffrey C. Wasmuth, John J. Altherr, Michael R. Schutte, Brian C. TI The DNA rearrangement associated with facioscapulohumeral muscular dystrophy involves a heterochromatin-associated repetitive element: implications for a role of chromatin structure in the pathogenesis of the disease SO CHROMOSOME RESEARCH LA English DT Article DE heterochromatin; telomere; repetitive DNA family; facioscapulohumeral muscular dystrophy; position effect variegation AB Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant form of muscular dystrophy. The FSHD locus has been linked to the most distal genetic markers on the long arm of chromosome 4. Recently, a probe was identified that detects an EcoRI fragment length polymorphism which segregates with the disease in most FSHD families. Within the EcoRI fragment lies a tandem array of 3.2 kb repeats. In several familial cases and four independent sporadic FSHD mutations, the variation in size of the EcoRI fragment was due to a decrease in copy number of the 3.2 kb repeats. To gain further insight into the relationship between the tandem array and FSHD, a single 3.2 kb repeat unit was characterized. Fluorescence in situ hybridization (FISH) demonstrates that the 3.2 kb repeat cross-hybridizes to several regions of heterochromatin in the human genome. In addition, DNA sequence analysis of the repeat reveals a region which is highly homologous to a previously identified family of heterochromatic repeats, LSau. FISH on interphase chromosomes demonstrates that the tandem array of 3.2 kb repeats lies within 215 kb of the 4q telomere. Together, these results suggest that the tandem array of 3.2 kb repeats, tightly linked to the FSHD locus, is contained in heterochromatin adjacent to the telomere. In addition, they are consistent with the hypothesis that the gene responsible for FSHD may be subjected to position effect variegation because of its proximity to telomeric heterochromatin. C1 [Winokur, Sara T.; Bengtsson, Ulla; Markovich, Rachelle P.; Wasmuth, John J.; Altherr, Michael R.] Univ Calif Irvine, Dept Biol Chem, Irvine, CA 92717 USA. [Feddersen, Julie; Mathews, Kathy D.; Bailey, Holly; Murray, Jeffrey C.; Schutte, Brian C.] Univ Iowa Hosp & Clin, Dept Pediat, MRC 216, Iowa City, IA 52242 USA. [Weiffenbach, Barbara] Collaborat Res Inc, Waltham, MA USA. [Altherr, Michael R.] LANL, Genom & Struct Biol Grp, Los Alamos, NM USA. RP Schutte, BC (reprint author), Univ Iowa Hosp & Clin, Dept Pediat, MRC 216, Iowa City, IA 52242 USA. EM bschutte@vaxa.weeg.uiowa.edu FU National Institutes of Health training grant [GM07311-18]; Muscular Dystrophy Association; National Institutes of Health [P30 HD-27748-03] FX We thank the FSHD consortium for presenting data prior to acceptance for publication, Margaret Malik for excellent technical assistance and the DNA Core Facility at the University of Iowa (Dave Moser, Director) for performing the automated DNA sequencing. This work was supported by an National Institutes of Health training grant to S. T. W. (GM07311-18), Muscular Dystrophy Association grants to K. D. M., M. R. A, B. C. S. and B. W., and a National Institutes of Health grant to B.C.S. (P30 HD-27748-03). NR 67 TC 118 Z9 121 U1 0 U2 1 PU SPRINGER PI DORDRECHT PA VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS SN 0967-3849 J9 CHROMOSOME RES JI Chromosome Res. PD MAY PY 1994 VL 2 IS 3 BP 225 EP 234 DI 10.1007/BF01553323 PG 10 WC Biochemistry & Molecular Biology; Genetics & Heredity SC Biochemistry & Molecular Biology; Genetics & Heredity GA V28DZ UT WOS:000208662800007 PM 8069466 ER PT J AU LIDSEY, JE AF LIDSEY, JE TI SOLUTIONS TO THE WHEELER-DEWITT EQUATION INSPIRED BY THE STRING EFFECTIVE ACTION SO CLASSICAL AND QUANTUM GRAVITY LA English DT Article ID QUANTUM COSMOLOGY; SUPERSTRING THEORY; BACKGROUND FIELDS; WAVE-FUNCTIONS; WORMHOLES; SYMMETRIES; UNIVERSE; QUANTIZATION; DIMENSIONS; SPACETIME AB The Wheeler-DeWitt equation is derived from the bosonic sector of the heterotic string effective action assuming a toroidal compactification. The spatially closed, higher-dimensional Friedmann-Robertson-Walker (FRW) cosmology is investigated and a suitable change of variables rewrites the equation in a canonical form. Real- and imaginary-phase exact solutions are found and a method of successive approximations is employed to find more general power-series solutions. The quantum cosmology of the Bianchi IX universe is also investigated and a class of exact solutions is found. RP LIDSEY, JE (reprint author), FERMILAB NATL ACCELERATOR LAB,NASA FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510, USA. NR 82 TC 14 Z9 14 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0264-9381 J9 CLASSICAL QUANT GRAV JI Class. Quantum Gravity PD MAY PY 1994 VL 11 IS 5 BP 1211 EP 1224 DI 10.1088/0264-9381/11/5/009 PG 14 WC Astronomy & Astrophysics; Physics, Multidisciplinary; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NR009 UT WOS:A1994NR00900009 ER PT J AU THOMPSON, EW TORRI, J SABOL, M SOMMERS, CL BYERS, S VALVERIUS, EM MARTIN, GR LIPPMAN, ME STAMPFER, MR DICKSON, RB AF THOMPSON, EW TORRI, J SABOL, M SOMMERS, CL BYERS, S VALVERIUS, EM MARTIN, GR LIPPMAN, ME STAMPFER, MR DICKSON, RB TI ONCOGENE-INDUCED BASEMENT-MEMBRANE INVASIVENESS IN HUMAN MAMMARY EPITHELIAL-CELLS SO CLINICAL & EXPERIMENTAL METASTASIS LA English DT Article DE BASEMENT MEMBRANE; HUMAN BREAST CANCER; INVASION; ONCOGENE; UVOMORULIN; VIMENTIN ID BREAST-CANCER CELLS; IV COLLAGENASE; METASTATIC PROPERTIES; EXTRACELLULAR-MATRIX; ADHESION MECHANISMS; KERATIN EXPRESSION; ESTROGEN-RECEPTOR; LAMININ RECEPTOR; TUMOR INVASION; VIMENTIN AB Expression of the intermediate filament protein vimentin, and loss of the cellular adhesion protein uvomorulin (E-cadherin) have been associated with increased invasiveness of established human breast cancer cell lines in vitro and in vivo. In the current study, we have further examined these relationships in oncogenically transformed human mammary epithelial cells. A normal human mammary epithelial strain, termed 184, was previously immortalized with benzo[a]pyrene, and two distinct sublines were derived (A1N4 and 184B5). These sublines were infected with retroviral vectors containing a single or two oncogenes of the nuclear, cytoplasmic, and plasma membrane-associated type (v-ras(H), v-ras(Ki), v-mos, SV40T and c-myc). All infectants have been previously shown to exhibit some aspects of phenotypic transformation. In the current study, cellular invasiveness was determined in vitro using Matrigel, a reconstituted basement membrane extract. Lineage-specific differences were observed with respect to low constitutive invasiveness and invasive changes after infection with ras, despite similar ras-induced transformation of each line. Major effects on cellular invasiveness were observed after infection of the cells with two different oncogenes (v-ras(H) + SV40T and v-ras(H) + v-mos). In contrast, the effects of single oncogenes were only modest or negligible. All oncogenic infectants demonstrated increased attachment to laminin, but altered secretion of the 72 kDa and 92 kDa gelatinases was not associated with any aspect of malignant progression. Each of the two highly invasive double oncogene transformants were vimentin-positive and uvomorulin-negative, a phenotype indicative of the epithelial-mesenchymal transition (EMT) previously associated with invasiveness of established human breast cancer cell lines, Weakly invasive untransformed mammary epithelial cells in this study were positive for both vimentin and uvomorulin, suggesting that uvomorulin may over-ride the otherwise vimentin-associated invasiveness. C1 GEORGETOWN UNIV,MED CTR,VINCENT T LOMBARDI CANC RES CTR,WASHINGTON,DC 20007. NIDR,BETHESDA,MD. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA. RP THOMPSON, EW (reprint author), GEORGETOWN UNIV,MED CTR,DEPT CELL BIOL,3800 RESERVOIR RD NW,WASHINGTON,DC 20007, USA. RI Thompson, Erik/A-1425-2009 OI Thompson, Erik/0000-0002-9723-4924 FU NCI NIH HHS [CA-24844, UO1-CA51908] NR 69 TC 57 Z9 60 U1 0 U2 0 PU RAPID SCIENCE PUBLISHERS PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8NH SN 0262-0898 J9 CLIN EXP METASTAS JI Clin. Exp. Metastasis PD MAY PY 1994 VL 12 IS 3 BP 181 EP 194 DI 10.1007/BF01753886 PG 14 WC Oncology SC Oncology GA NQ407 UT WOS:A1994NQ40700001 PM 8194193 ER PT J AU SCOVEL, C WEINSTEIN, A AF SCOVEL, C WEINSTEIN, A TI FINITE-DIMENSIONAL LIE-POISSON APPROXIMATIONS TO VLASOV-POISSON EQUATIONS SO COMMUNICATIONS ON PURE AND APPLIED MATHEMATICS LA English DT Article ID SYMPLECTIC INTEGRATION; HAMILTONIAN-SYSTEMS; CONSTRUCTION; DYNAMICS; SCHEMES AB Many of the basic equations of conservative continuum mechanics (Euler, Vlasov-Poisson, Vlasov-Maxwell, MHD, etc.) are Hamiltonian systems with respect to Lie-Poisson brackets on dual spaces of infinite dimensional Lie algebras. The development of Lie-Poisson integrators for finite dimensional Lie-Poisson systems has shown that they are superior in the numerical simulations of these systems, especially with regard to long term phenomena. This paper shows how to truncate one of these systems, the Vlasov-Poisson equation of plasma physics, to a finite dimensional Lie-Poisson system. This requires replacing the functions on single-particle phase space, with their Poisson bracket Lie algebra structure, by a finite dimensional Lie algebra. Replacing the densities by their moments of order up to k about a fixed reference point corresponds to replacing the functions by their Taylor expansions up to order k. Unfortunately, these truncated Taylor expansions do not form a Lie algebra, since the functions which vanish through order k do not form an ideal under Poisson bracket. Geometrically, this corresponds to the fact that canonical transformations which fix the reference point do not form a normal subgroup. Introducing the location of a reference point in phase space as an extra variable and truncating with respect to this moving point turns out to decouple the ''location'' from ''shape'' coordinates of a lump of density in phase space, as far as the Poisson bracket is concerned. One can then replace the shape coordinates by a finite number of moments. The central result of the paper is a construction of the decoupling map described above in the general context of the decomposition of a Lie group as a product of subgroups. The main theorem is first proved by the general theory of Poisson reduction, then by explicit calculation, and lastly by showing that the Poisson isomorphism follows from the lift of a natural groupoid isomorphism. The groupoid aspect of the theory also provides natural Poisson maps, useful in the application of Ruth-type integration techniques, which do not seem easily derivable from the general theory of Poisson reduction. (C) 1994 John Wiley & Sons, Inc. C1 UNIV CALIF BERKELEY,BERKELEY,CA 94720. RP SCOVEL, C (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544, USA. NR 41 TC 10 Z9 10 U1 0 U2 2 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0010-3640 J9 COMMUN PUR APPL MATH JI Commun. Pure Appl. Math. PD MAY PY 1994 VL 47 IS 5 BP 683 EP 709 DI 10.1002/cpa.3160470505 PG 27 WC Mathematics, Applied; Mathematics SC Mathematics GA PA050 UT WOS:A1994PA05000004 ER PT J AU KALUZA, M AF KALUZA, M TI ANALYTICAL LANCZOS METHOD - QUANTUM EIGENSTATES OF ANHARMONIC-OSCILLATORS IN ONE OR MORE DIMENSIONS SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article ID GUSTAVSON NORMAL-FORM; ENERGY-LEVELS; QUANTIZATION; MECHANICS; SYSTEMS; MODEL AB The analytical Lanczos method is a simple method to calculate the eigenstates of quantum-mechanical Hamiltonians of systems with several degrees of freedom. High precision eigenvalues and eigenfunctions are obtained for the anharmonic oscillator, and for two, three and four coupled anharmonic oscillators, by diagonalizing small tridiagonal matrices. RP KALUZA, M (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. NR 26 TC 11 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD MAY PY 1994 VL 79 IS 3 BP 425 EP 446 DI 10.1016/0010-4655(94)90186-4 PG 22 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA NP118 UT WOS:A1994NP11800006 ER PT J AU JADACH, S WARD, BFL WAS, Z AF JADACH, S WARD, BFL WAS, Z TI THE MONTE-CARLO PROGRAM KORALZ VERSION-4.0 FOR LEPTON OR QUARK PAIR PRODUCTION AT LEP/SLC ENERGIES SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article ID RADIATIVE-CORRECTIONS; STANDARD MODEL; Z0; ELECTROWEAK; DECAYS; MASS; SIMULATION; RESONANCE; ASYMMETRY; SLC/LEP AB A Monte Carlo program for tau pair production and decay applicable to the experiments in e+e- colliders in the Z resonance energy range is presented. The program includes initial and final state bremsstrahlung corrections up to the O(alpha2) (with exclusive exponentiation), and O(alpha) electroweak corrections. More than twenty distinct tau decay modes can be generated: (a) leptonic modes tau- --> nunue-BAR(gamma) and nunumu-BAR(gamma); (b) one-meson modes, nutau- and nuK-; (c) two-meson modes, nu(pi-pi0}rho-, nu(K-pi0}K*- and nu{K0pi-}K*-: (d) three-meson modes, nu{pi-2pi0}a1-, nu{2pi-pi+}a1-, nuK+K-pi-, nuK0K0pi-BAR, nuK-K0pi0BAR, nuK-pi0pi0, nuK-pi-pi+, nuK0pi0pi- and nunpi-pi0; (e) four-pion modes, nupi-3pi0, and nu2pi-pi+pi0 (including the omegapi- contribution); (f) multi-pion modes, nun +/-,0 with n > 4; and finally the decay tau- --> nupi- pi0gamma from the omega --> pigamma Complete O(alpha) QED corrections are included in the leptonic decay channels, and for other decay channels an interface is provided to the PHOTOS Monte Carlo generator for approximate simulation of the QED corrections. The program includes three libraries of pure electroweak corrections from three independent groups of authors. The program can also be used for the generation of final states different from tau+tau- pairs, i.e., it is able to generate mu+mu-, nunuBAR, and under some restrictions uuBAR, ddBAR, ccBAR, ssBAR and bbBAR final states. C1 CERN,DIV THEORY,CH-1211 GENEVA 23,SWITZERLAND. INST NUCL PHYS,PL-31342 KRAKOW,POLAND. STANFORD UNIV,SLAC,STANFORD,CA 94309. UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. NR 47 TC 417 Z9 417 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD MAY PY 1994 VL 79 IS 3 BP 503 EP 522 DI 10.1016/0010-4655(94)90190-2 PG 20 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA NP118 UT WOS:A1994NP11800010 ER PT J AU BUIJS, A LANGEVELD, WGJ LEHTO, MH MILLER, DJ AF BUIJS, A LANGEVELD, WGJ LEHTO, MH MILLER, DJ TI TWOGEN - A SIMPLE MONTE-CARLO GENERATOR FOR 2-PHOTON REACTIONS SO COMPUTER PHYSICS COMMUNICATIONS LA English DT Article ID LOWEST ORDER CALCULATIONS; PHOTON-PHOTON COLLISIONS; RADIATIVE-CORRECTIONS; PAIR PRODUCTION; SIMULATION AB TWOGEN samples the transverse-transverse luminosity function for real and virtual photons, then weights events with any user-supplied cross section sigma(TT)(gammagamma --> X) in a ''hit or miss'' sampling, using a simple method to avoid the singularity at the minimum electron angle theta(min) = 0. Events within defined kinematic limits are accepted and the corresponding cross section is estimated, together with the effective luminosity of the run. Functions implemented for sigma(TT) include the production cross sections for lepton pairs, for the formation of narrow resonances and for hadron production in tagged, deep inelastic scattering. A comparison is made with an existing Monte Carlo generator and a simple analytic approximation. C1 UNIV BOLOGNA,I-40126 BOLOGNA,ITALY. STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94305. UNIV LONDON UNIV COLL,DEPT PHYS & ASTRON,LONDON WC1E 6BT,ENGLAND. RP BUIJS, A (reprint author), CERN,CH-1211 GENEVA 23,SWITZERLAND. NR 21 TC 39 Z9 39 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0010-4655 J9 COMPUT PHYS COMMUN JI Comput. Phys. Commun. PD MAY PY 1994 VL 79 IS 3 BP 523 EP 532 DI 10.1016/0010-4655(94)90191-0 PG 10 WC Computer Science, Interdisciplinary Applications; Physics, Mathematical SC Computer Science; Physics GA NP118 UT WOS:A1994NP11800011 ER PT J AU FERNANDEZ, J RUNDLE, JB AF FERNANDEZ, J RUNDLE, JB TI FORTRAN PROGRAM TO COMPUTE DISPLACEMENT, POTENTIAL, AND GRAVITY CHANGES RESULTING FROM A MAGMA INTRUSION IN A MULTILAYERED EARTH MODEL SO COMPUTERS & GEOSCIENCES LA English DT Article DE DEFORMATION MODEL; MULTILAYERED EARTH MODEL; DISPLACEMENT; GRAVITY AND POTENTIAL CHANGES ID DEFORMATION AB We describe theoretical and computational methods for the calculation of the deformation, gravity, and potential change resulting from a point source of magma injection into a layered, elastic-gravitational Earth model. In our calculations we consider a medium composed of two distinct layers overlaying a half space. The source can be located in either of the layers or the half space. The deformation. potential, and gravity changes are expressed as integral solutions of partial differential equations. We studied the behavior of the different kernels. The effect of a magma intrusion can be expressed as the sum of the corresponding effects of a point mass and a center of expansion. The FORTRAN program GRAV1 used to compute the solutions is described. Finally, as an example, we present results obtained for a mass point and a center of expansion located at different depths in a medium. C1 LAWRENCE LIVERMORE NATL LAB,DEPT EARTH SCI,LIVERMORE,CA 94550. RP FERNANDEZ, J (reprint author), UCM,FAC CIENCIAS MATEMAT,CSIC,INST ASTRON & GEODESIA,CIUDAD UNIV,E-28040 MADRID,SPAIN. RI Fernandez, Jose/K-1669-2014 OI Fernandez, Jose/0000-0001-5745-3527 NR 14 TC 22 Z9 22 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0098-3004 J9 COMPUT GEOSCI JI Comput. Geosci. PD MAY PY 1994 VL 20 IS 4 BP 461 EP 510 DI 10.1016/0098-3004(94)90079-5 PG 50 WC Computer Science, Interdisciplinary Applications; Geosciences, Multidisciplinary SC Computer Science; Geology GA NR578 UT WOS:A1994NR57800002 ER PT J AU FUJITA, E BRUNSCHWIG, BS OGATA, T YANAGIDA, S AF FUJITA, E BRUNSCHWIG, BS OGATA, T YANAGIDA, S TI TOWARD PHOTOCHEMICAL CARBON-DIOXIDE ACTIVATION BY TRANSITION-METAL COMPLEXES SO COORDINATION CHEMISTRY REVIEWS LA English DT Article; Proceedings Paper CT 10th International Symposium on Photochemistry and Photophysics of Coordination Compounds CY JUL 26-30, 1993 CL SENDAI, JAPAN ID TERPHENYL-CATALYZED PHOTOREDUCTION; ELECTROCATALYTIC REDUCTION; CO2; MACROCYCLES; BINDING; COBALT; OLIGO(PARA-PHENYLENES); TETRAAZAMACROCYCLES; PHOTOCATALYSIS; TRIETHYLAMINE AB Nickel and cobalt complexes of 14-membered tetraazamacrocycles mediate electron transfer and produce CO in the photochemical reduction of CO2. Two integrated systems for the CO2 reduction are discussed: (1) photophysical properties of bifunctional supramolecules, Ru(bpy)2(bpy-L10M)4+ (bpy = 2,2'-bipyridine, bpy-L10 = 1-(2,2'-bipyridin-6-ylmethyl)-1,4,8,11-tetraazacyclotetradecane, M = H-2, Ni) and its limitation as a photocatalyst; (2) advantages of multimolecular system with p-terphenyl as a photosensitizer, a cobalt macrocycle as an electron mediator, and a tertiary amine as a sacrificial electron donor. C1 OSAKA UNIV,FAC ENGN,OSAKA,JAPAN. RP FUJITA, E (reprint author), BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973, USA. RI Brunschwig, Bruce/G-4249-2011; Fujita, Etsuko/D-8814-2013 NR 20 TC 77 Z9 77 U1 2 U2 28 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0010-8545 J9 COORDIN CHEM REV JI Coord. Chem. Rev. PD MAY PY 1994 VL 132 BP 195 EP 200 DI 10.1016/0010-8545(94)80040-5 PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA NM692 UT WOS:A1994NM69200025 ER PT J AU PIPER, J POGGENSEE, M HILL, W JENSEN, R JI, L POOLE, I STARK, M SUDAR, D AF PIPER, J POGGENSEE, M HILL, W JENSEN, R JI, L POOLE, I STARK, M SUDAR, D TI AUTOMATIC FLUORESCENCE METAPHASE FINDER SPEEDS TRANSLOCATION SCORING IN FISH PAINTED CHROMOSOMES SO CYTOMETRY LA English DT Article DE ABERRATION SCORING; CCD CAMERA; CHROMOSOME; IMAGE ANALYSIS; IN SITU HYBRIDIZATION; REGION OF INTEREST ANALYSIS; SCANNING ID FAST INTERVAL PROCESSOR; INSITU HYBRIDIZATION; RADIATION; ABERRATIONS; PERFORMANCE AB A fluorescence metaphase finder was constructed with commercially available hardware and a standard Unix workstation. Its accuracy was measured in terms of the number of false positive and false negative detected metaphases on a variety of different slide preparations. The metaphase finder was used in a translocation scoring experiment in which metaphase preparations of human peripheral blood lymphocytes were hybridized with whole chromosome probes to chromosomes #1, #2, and #4. The automatic finder presented metaphases to the cytogeneticist, centered in the eyepieces at x 63. The cytogeneticist's scores of analyzable metaphases and of painted chromosomes involved in rearrangements were recorded. The time for the analysis was recorded and compared to the time to analyze a similar number of cells in a purely visual experiment in which the cytogeneticist scanned for cells and analyzed them, both at x 63. The results showed that, neglecting the machine time spent scanning unattended, the amount of time required for the analysis was reduced by a factor of three. Furthermore, in this experiment the metaphase finder found more scorable metaphases than the cytogeneticist found by visual scanning. Machine-assisted scoring had additional, less quantifiable, benefits; notably that digital images of metaphases sometimes assisted the analysis of chromosome rearrangements, that cells could be revisited easily, and that the analysis was much less fatiguing. (C) 1994 Wiley-Liss, Inc. C1 UNIV CALIF SAN FRANCISCO,DEPT LAB MED,DIV MOLEC CYTOMETRY,SAN FRANCISCO,CA 94143. MRC,HUMAN GENET UNIT,EDINBURGH,MIDLOTHIAN,SCOTLAND. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA. OI Sudar, Damir/0000-0002-2510-7272 FU NCI NIH HHS [NCI Y01-CP-10561] NR 22 TC 16 Z9 16 U1 2 U2 2 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0196-4763 J9 CYTOMETRY JI Cytometry PD MAY 1 PY 1994 VL 16 IS 1 BP 7 EP 16 DI 10.1002/cyto.990160103 PG 10 WC Biochemical Research Methods; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA NH120 UT WOS:A1994NH12000002 PM 8033737 ER PT J AU STOCKMAN, HW AF STOCKMAN, HW TI OPTIMIZING MATRIX MATH ON THE PENTIUM SO DR DOBBS JOURNAL LA English DT Article C1 SANDIA NATL LABS,DEPT GEOCHEM,ALBUQUERQUE,NM 87185. NR 6 TC 0 Z9 0 U1 0 U2 0 PU MILLER FREEMAN, INC PI SAN MATEO PA 411 BOREL AVE, SAN MATEO, CA 94402-3522 SN 1044-789X J9 DR DOBBS J JI Dr. Dobbs J. PD MAY PY 1994 VL 19 IS 5 BP 52 EP & PG 0 WC Computer Science, Software Engineering SC Computer Science GA NC142 UT WOS:A1994NC14200013 ER PT J AU LOEHLE, C JOHNSON, P AF LOEHLE, C JOHNSON, P TI A FRAMEWORK FOR MODELING MICROBIAL TRANSPORT AND DYNAMICS IN THE SUBSURFACE SO ECOLOGICAL MODELLING LA English DT Article DE MICROORGANISM; RESCALING; SUBSURFACE ID SATURATED HYDRAULIC CONDUCTIVITY; CONTAMINATED SANDY AQUIFER; POROUS-MEDIA; FILTRATION THEORY; ESCHERICHIA-COLI; AEROBIC-BACTERIA; PERCOLATION; SEDIMENTS; MICROORGANISMS; COMPETITION AB A framework and specific models are presented for modeling microbial transport and dynamics in the subsurface. To create a more widely applicable model, spatial heterogeneity and various rescalings need to be incorporated. Rescalings occur when a change in some variable changes the structure of the model. Microbes at high abundance can cause a rescaling of transport flow paths, thereby causing a rescaling of standard transport equations. We present a two-stage modeling approach for dealing with these rescalings. At fine scales, percolation modeling of particle transport can allow the interactions of soil heterogeneity and microbial behaviors to be represented. The results at this scale can be used to derive effective parameters for coarser scale simulations. Percolation models are again used at the coarser scale to define flow paths. Regions within the subsurface are modeled as chemostats. Combining these two approaches yields a chemostat-network percolation modeling framework. This framework can be used for scaling up laboratory studies to the field, for modeling heterogeneous systems, for studying colonization and persistence, and for studying selection processes, among other applications. C1 MICHIGAN STATE UNIV,CTR MICROBIAL ECOL,E LANSING,MI 48824. RP LOEHLE, C (reprint author), ARGONNE NATL LAB,DIV ENVIRONM RES,ARGONNE,IL 60439, USA. NR 60 TC 8 Z9 8 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3800 J9 ECOL MODEL JI Ecol. Model. PD MAY PY 1994 VL 73 IS 1-2 BP 31 EP 49 DI 10.1016/0304-3800(94)90096-5 PG 19 WC Ecology SC Environmental Sciences & Ecology GA NM453 UT WOS:A1994NM45300003 ER PT J AU TAHERI, BA KNIGHT, RT SMITH, RL AF TAHERI, BA KNIGHT, RT SMITH, RL TI A DRY ELECTRODE FOR EEG RECORDING SO ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY LA English DT Article DE DRY EEG ELECTRODE; INSULATED EEG ELECTRODE ID LOCALIZATION; BRAIN AB This paper describes the design, fabrication and testing of a prototype dry surface electrode for EEG signal recording. The new dry electrode has the advantages of no need for skin preparation or conductive paste, potential for reduced sensitivity to motion artifacts and an enhanced signal-to-noise ratio. The electrode's sensing element is a 3 mm stainless steel disk which has a 2000 Angstrom A (200 nm) thick nitride coating deposited onto one side. The back side of the disk is attached to an impedance converting amplifier. The prototype electrode was mounted on a copper plate attached to the scalp by a Velcro strap. The performance of this prototype dry electrode was compared to commercially available wet electrodes in 3 areas of electroencephalogram (EEG) recording: (1) spontaneous EEG, (2) sensory evoked potentials, and (3) cognitive evoked potentials. In addition to the raw EEG, the power spectra of the signals from both types of electrodes were also recorded. The results suggest that the dry electrode performs comparably to conventional electrodes for all types of EEG signal analysis. This new electrode may be useful for the production of high resolution surface maps of brain activity where a large number of electrodes or prolonged recording times are required. C1 LAWRENCE LIVERMORE NATL LAB,CTR NEUROSCI,DAVIS,CA 95616. LAWRENCE LIVERMORE NATL LAB,DEPT NEUROL,DAVIS,CA 95616. LAWRENCE LIVERMORE NATL LAB,DEPT ELECT & COMP ENGN,DAVIS,CA 95616. RP TAHERI, BA (reprint author), LAWRENCE LIVERMORE NATL LAB,BIOMED ENGN GRAD GRP,1544 NEWTON COURT,DAVIS,CA 95616, USA. RI Smith, Rosemary/H-7359-2015 OI Smith, Rosemary/0000-0001-8483-6777 FU NINDS NIH HHS [NINDS NS21135] NR 32 TC 42 Z9 42 U1 4 U2 13 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0013-4694 J9 ELECTROEN CLIN NEURO JI Electroencephalogr. Clin. Neurophysiol. PD MAY PY 1994 VL 90 IS 5 BP 376 EP 383 DI 10.1016/0013-4694(94)90053-1 PG 8 WC Engineering, Biomedical; Clinical Neurology SC Engineering; Neurosciences & Neurology GA NN360 UT WOS:A1994NN36000006 PM 7514984 ER PT J AU SATHAYE, J TYLER, S GOLDMAN, N AF SATHAYE, J TYLER, S GOLDMAN, N TI TRANSPORTATION, FUEL USE AND AIR-QUALITY IN ASIAN CITIES SO ENERGY LA English DT Article AB While in almost every country in the world urbanization has been accompanied by more intensive use of motorized transportation, in the cities of developing Asia these processes have occurred more rapidly and under different conditions. Planners are not prepared to deal with the pace of motorization caused by the startling speed of urbanization and growth of disposable income. In addition, planning responses have been constrained by inadequate resources, inappropriate administrative and institutional arrangements for urban management and lack of expertise, all in the face of competing demands for resources elsewhere in the public sector. This article highlights some of the general transportation trends in Asian cities and discusses some of the possible institutional solutions for improving these urban transport systems. C1 INT DEV RES CTR,SINGAPORE 9124,SINGAPORE. RP SATHAYE, J (reprint author), LAWRENCE BERKELEY LAB,INT ENERGY STUDIES GRP,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 41 TC 11 Z9 12 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0360-5442 J9 ENERGY JI Energy PD MAY PY 1994 VL 19 IS 5 BP 573 EP 586 DI 10.1016/0360-5442(94)90053-1 PG 14 WC Thermodynamics; Energy & Fuels SC Thermodynamics; Energy & Fuels GA NJ769 UT WOS:A1994NJ76900009 ER PT J AU SMITH, KR APTE, MG MA, YQ WONGSEKIARTTIRAT, W KULKARNI, A AF SMITH, KR APTE, MG MA, YQ WONGSEKIARTTIRAT, W KULKARNI, A TI AIR-POLLUTION AND THE ENERGY LADDER IN ASIAN CITIES SO ENERGY LA English DT Article ID MORTALITY; EXPOSURE AB Household fuel switching from lower to higher quality fuels, i.e. movement up the ''energy ladder,'' generally leads to substantially lower emissions of health-damaging pollutants. The extent to which human exposures are reduced is difficult to predict, however, because of interactions due to penetration of outdoor pollutants into homes and vice versa. In order to help answer the question of how much exposures might be reduced by movement up the energy ladder, a three-city household air pollution study covering particulates (PM10), nitrogen dioxide (NO2), and carbon monoxide (CO) was conducted in and near households spanning the most important current steps in each city's energy ladder. Steps examined were biomass-kerosene-gas in Pune, India; coal-gas in Beijing, China; and charcoal-gas in Bangkok, Thailand. In most instances, 24-hour sampling was conducted and some personal monitoring was undertaken during cooking periods. Preliminary calculations of the exposure and health implications of fuel switching are presented. C1 LAWRENCE BERKELEY LAB,EED,BERKELEY,CA 94720. TSING HUA UNIV,ITEESA,BEIJING 100084,PEOPLES R CHINA. CHULALONGKORN UNIV,SRI,BANGKOK 5,THAILAND. RP SMITH, KR (reprint author), ENV,EAST WEST CTR,HONOLULU,HI 96848, USA. NR 32 TC 91 Z9 95 U1 1 U2 16 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0360-5442 J9 ENERGY JI Energy PD MAY PY 1994 VL 19 IS 5 BP 587 EP 600 DI 10.1016/0360-5442(94)90054-X PG 14 WC Thermodynamics; Energy & Fuels SC Thermodynamics; Energy & Fuels GA NJ769 UT WOS:A1994NJ76900010 ER PT J AU TYLER, S SATHAYE, J GOLDMAN, N AF TYLER, S SATHAYE, J GOLDMAN, N TI ENERGY USE IN ASIAN CITIES - PREFACE SO ENERGY LA English DT Editorial Material C1 LAWRENCE BERKELEY LAB,INT ENERGY STUDIES GRP,BERKELEY,CA 94720. RP TYLER, S (reprint author), INT DEV RES CTR,TANGLIN POB 101,SINGAPORE 9124,SINGAPORE. NR 1 TC 0 Z9 0 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0360-5442 J9 ENERGY JI Energy PD MAY PY 1994 VL 19 IS 5 BP R5 EP R6 DI 10.1016/0360-5442(94)90045-0 PG 2 WC Thermodynamics; Energy & Fuels SC Thermodynamics; Energy & Fuels GA NJ769 UT WOS:A1994NJ76900001 ER PT J AU DYRKACZ, GR BLOOMQUIST, CAA AF DYRKACZ, GR BLOOMQUIST, CAA TI HYPERFINE GRINDING OF COAL SO ENERGY & FUELS LA English DT Article ID SEPARATION; MACERALS AB Coal was subjected to intensive grinding to produce submicrometer particles. This was done in two stages. Ultrafine coal produced by fluid energy mill grinding was further ground in a planetary ball mill or attritor mill. The grinding process was monitored by density gradient separation and surface area measurements. Conditions were established to produce coal in the 0.05-1 mum size range with 3 h of grinding. Several different slurry solvents were examined for grinding efficiency. Extensive accretion of coal particles to produce homogeneous particles was found to be a major problem. In several instances there appeared to be a low melting phase produced (approximately 65-degrees-C) which cemented the fine particles together during vacuum drying. The submicrometer coal also interacted with the surfactant used in density gradient analysis resulting in particle size dependent density distributions. Two cases were found that may have circumvented accretion problems: grinding in tetrabutylammonium hydroxide/pyridine/methanol and attritor milling in a methanol slurry at <-50-degrees-C. RP DYRKACZ, GR (reprint author), ARGONNE NATL LAB,DIV CHEM,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 55 TC 2 Z9 3 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAY-JUN PY 1994 VL 8 IS 3 BP 680 EP 689 DI 10.1021/ef00045a024 PG 10 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA NN798 UT WOS:A1994NN79800025 ER PT J AU LEE, JW TEVAULT, CV BLANKINSHIP, SL COLLINS, RT GREENBAUM, E AF LEE, JW TEVAULT, CV BLANKINSHIP, SL COLLINS, RT GREENBAUM, E TI PHOTOSYNTHETIC WATER-SPLITTING - IN-SITU PHOTOPRECIPITATION OF METALLOCATALYSTS FOR PHOTOEVOLUTION OF HYDROGEN AND OXYGEN SO ENERGY & FUELS LA English DT Article ID PLATINIZED CHLOROPLASTS; PHOTOCATALYTIC MATERIAL AB Using the technique of in situ photoprecipitation, a comparative study of the structurally homologous ionic species hexachloroplatinate ([PtCl6]2-), hexachloroosmiate ([OsCl6]2-), and hexachloroiridates ([IrCl6]2- and [IrCl6]3-) was conducted for photoconversion to metallocatalysts for photosynthetic hydrogen evolution. As with earlier [PtCl6]2- studies, [OsCl6]2- can be photoconverted to a metallocatalyst at photosystem I (PSI), although at a rate about 50% slower than that of [PtCl6]2-. However, once photoprecipitated, its catalytic action for H-2 production was 3 times as high as that of metallic platinum. Simultaneous photoevolution of O2 and H-2 was observed in [OsCl6-2-photoprecipitated thylakoids. Maximum hydrogen evolution rate was 113 nmol-h-1.mg chl-1. Surprisingly, neither [IrCl6]2-- nor [IrCl6]3-treated thylakoids were able to produce H2. Analysis indicated that [IrCl6]2- was able to accept only one electron by transformation to [IrCl6]3- which was completely unable to acquire subsequent electrons from PSI. The inability of [IrCl6]2- to be reduced to metallic iridium is presumably due to a high energy level barrier of [IrCl6]3- reduction. C1 OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831. NR 12 TC 32 Z9 32 U1 2 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0887-0624 J9 ENERG FUEL JI Energy Fuels PD MAY-JUN PY 1994 VL 8 IS 3 BP 770 EP 773 DI 10.1021/ef00045a034 PG 4 WC Energy & Fuels; Engineering, Chemical SC Energy & Fuels; Engineering GA NN798 UT WOS:A1994NN79800035 ER PT J AU DUNN, ML AF DUNN, ML TI THE EFFECTS OF CRACK FACE BOUNDARY-CONDITIONS ON THE FRACTURE-MECHANICS OF PIEZOELECTRIC SOLIDS SO ENGINEERING FRACTURE MECHANICS LA English DT Article AB The effects of crack face boundary conditions on the fracture mechanics of piezoelectric solids are studied. In previous works the assumption that in addition to being traction free, a slit crack is impermeable to electric fields has yielded the appealing result that an applied electric field can retard crack growth. Here, more accurate crack face boundary conditions regarding the electric fields are employed by analyzing a permeable elliptical flaw in a piezoelectric solid, and the results illustrate that the impermeable assumption can lead to significant errors regarding the effects of the electric fields on crack propagation based on an energy release rate criterion. The relatively simple closed form expressions that are obtained can be used as benchmark solutions for further finite element analysis of piezoelectric crack problems. C1 SANDIA NATL LABS, ALBUQUERQUE, NM 87185 USA. OI DUNN, MARTIN/0000-0002-4531-9176 NR 23 TC 244 Z9 250 U1 0 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0013-7944 EI 1873-7315 J9 ENG FRACT MECH JI Eng. Fract. Mech. PD MAY PY 1994 VL 48 IS 1 BP 25 EP 39 DI 10.1016/0013-7944(94)90140-6 PG 15 WC Mechanics SC Mechanics GA NK576 UT WOS:A1994NK57600004 ER PT J AU FELTON, JS TURTELTAUB, KW AF FELTON, JS TURTELTAUB, KW TI ACCELERATOR MASS-SPECTROMETRY FOR MEASURING LOW-DOSE CARCINOGEN BINDING TO DNA SO ENVIRONMENTAL HEALTH PERSPECTIVES LA English DT Note C1 LAWRENCE LIVERMORE NATL LAB,BIOL & BIOTECHNOL PROGRAM,LIVERMORE,CA 94550. RP FELTON, JS (reprint author), LAWRENCE LIVERMORE NATL LAB,MOLEC TOXICOL GRP,LIVERMORE,CA 94550, USA. NR 6 TC 10 Z9 10 U1 0 U2 1 PU NATL INST ENVIRON HEALTH SCI PI RES TRIANGLE PK PA PO BOX 12233, RES TRIANGLE PK, NC 27709 SN 0091-6765 J9 ENVIRON HEALTH PERSP JI Environ. Health Perspect. PD MAY PY 1994 VL 102 IS 5 BP 450 EP 452 DI 10.2307/3432039 PG 3 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA NU651 UT WOS:A1994NU65100017 PM 8593847 ER PT J AU GOMBERT, D AF GOMBERT, D TI SOIL WASHING AND RADIOACTIVE CONTAMINATION SO ENVIRONMENTAL PROGRESS LA English DT Article RP GOMBERT, D (reprint author), WESTINGHOUSE IDAHO NUCL CO INC,POB 4000,IDAHO FALLS,ID 83415, USA. NR 0 TC 4 Z9 4 U1 0 U2 1 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0278-4491 J9 ENVIRON PROG JI Environ. Prog. PD MAY PY 1994 VL 13 IS 2 BP 138 EP 142 DI 10.1002/ep.670130218 PG 5 WC Engineering, Environmental; Engineering, Chemical; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA NM719 UT WOS:A1994NM71900011 ER PT J AU BREWSTER, MD PASSMORE, RJ AF BREWSTER, MD PASSMORE, RJ TI USE OF ELECTROCHEMICAL IRON GENERATION FOR REMOVING HEAVY-METALS FROM CONTAMINATED GROUNDWATER SO ENVIRONMENTAL PROGRESS LA English DT Article AB This paper utilizes data from two pilot studies conducted at Superfund Sites to discuss the electrochemical iron addition process developed by Andco Environmental Processes, Inc. Electrical current and steel electrodes were used to put ferrous and hydroxyl ions into solution. Once added, the chemistry was properly manipulated to provide coprecipitation and adsorption conditions capable of simultaneously removing a wide variety of heavy metals. The goals of the two projects were distinctly different. At the first site, conversion of ferrous ions to the ferric state resulted in thorough reduction of hexavalent chromium to trivalent chromium. Observations and results from this study are used to discuss system design, sludge production, and operating costs. At the second location, high concentrations of many metals required removal. The presence of arsenic necessitated chemically induced oxidation. Hydrogen peroxide was introduced to convert Fe+2 to Fe+3 and arsenite to arsenate. By efficiently shifting the equilibrium state and adjusting pH to create conditions for maximum anion adsorption, an arsenic removal efficiency of over 99.8 percent was obtained. Proper process application resulted in simultaneous removal of aluminum, arsenic, cadmium, chromium, lead, mercury, nickel, selenium, thallium, and zinc. Also, when necessary treatment conditions were provided and maintained, metals removal by three major mechanisms resulted in iron matrices that passed regulatory levels listed in conjunction with the Toxicity Characteristic Leaching Procedures (TCLP). RP BREWSTER, MD (reprint author), ARGONNE NATL LAB,ARGONNE,IL 60439, USA. NR 0 TC 20 Z9 27 U1 0 U2 7 PU AMER INST CHEMICAL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0278-4491 J9 ENVIRON PROG JI Environ. Prog. PD MAY PY 1994 VL 13 IS 2 BP 143 EP 148 PG 6 WC Engineering, Environmental; Engineering, Chemical; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA NM719 UT WOS:A1994NM71900012 ER PT J AU MCNAB, WW NARASIMHAN, TN AF MCNAB, WW NARASIMHAN, TN TI DEGRADATION OF CHLORINATED HYDROCARBONS AND GROUNDWATER GEOCHEMISTRY - A FIELD-STUDY SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID ORGANIC-COMPOUNDS; TRANSFORMATIONS; ETHENES AB Published laboratory studies suggest that certain chlorinated hydrocarbons are subject to chemical degradation in groundwater through abiotic and biologically-mediated processes. However, relatively few field investigations have been conducted on the degradation of these compounds. We examine the issue of degradation with regard to several chlorinated aliphatics dissolved in groundwater at the Lawrence Livermore National Laboratory in California. The highly oxidized state of the local groundwater, as indicated by geochemical observations suggests that reductive degradation reactions of chlorinated ethenes and ethanes are not thermodynamically or microbially favorable. In contrast, it is known that certain chlorinated compounds, such as 1,1,1-TCA, may degrade through redox-independent elimination or hydrolysis reactions. Indeed, statistical analyses and numerical modeling have provided evidence for the nonredox-driven transformation of 1,1,1-TCA to 1,1-DCE and to possibly acetic acid at the site. Similar analyses conducted for PCE and TCE failed to indicate any evidence for reductive dehalogenation. C1 UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,364 HEARST MIN BLDG,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV EARTH SCI,BERKELEY,CA 94720. NR 21 TC 28 Z9 28 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD MAY PY 1994 VL 28 IS 5 BP 769 EP 775 DI 10.1021/es00054a005 PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA NJ324 UT WOS:A1994NJ32400009 PM 22191815 ER PT J AU NIMLOS, MR MILNE, TA MCKINNON, JT AF NIMLOS, MR MILNE, TA MCKINNON, JT TI PHOTOTHERMAL OXIDATIVE DESTRUCTION OF CHLORONAPHTHALENE SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Article ID MOLECULAR CHARACTERIZATION; PYROLYSIS; HYDROCARBONS; BIOMASS; WASTES AB We have investigated the feasibility of using concentrated solar photons for the destruction of hazardous waste. Chloronaphthalene was chosen as the model compound for study, and light intensities were used that are close to those expected from a high-flux solar furnace. The results showed that the addition of ultraviolet photons to a reactor greatly accelerates the reaction rate for oxidation. The light intensity has an exponential effect on the degree of destruction, as predicted by earlier studies. Derived primary quantum yields in the gas phase are much higher than reported values in organic liquids: 0.2 for gas phase vs 0.002-0.005 for liquids. The products of incomplete oxidation were tentatively identified, and similar products were found in the presence or absence of ultraviolet light. At low temperatures, the ultraviolet light appeared to promote the formation of these products, while at higher temperatures, the light enhanced the destruction of the byproducts. It was found that, at a given destruction level, the product slate was similar with and without the light. C1 COLORADO SCH MINES,DEPT CHEM ENGN & PETR REFINING,GOLDEN,CO 80401. RP NIMLOS, MR (reprint author), NATL RENEWABLE ENERGY LAB,PROC RES BRANCH,GOLDEN,CO 80401, USA. NR 18 TC 4 Z9 4 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD MAY PY 1994 VL 28 IS 5 BP 816 EP 822 DI 10.1021/es00054a012 PG 7 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA NJ324 UT WOS:A1994NJ32400016 PM 22191822 ER PT J AU BERTSCH, PM HUNTER, DB SUTTON, SR BAJT, S RIVERS, ML AF BERTSCH, PM HUNTER, DB SUTTON, SR BAJT, S RIVERS, ML TI IN-SITU CHEMICAL SPECIATION OF URANIUM IN SOILS AND SEDIMENTS BY MICRO-X-RAY ABSORPTION-SPECTROSCOPY SO ENVIRONMENTAL SCIENCE & TECHNOLOGY LA English DT Note ID SURFACE COMPLEXES; WATER INTERFACE; OXIDE SURFACES; EXAFS; ION C1 UNIV CHICAGO, DEPT GEOPHYS SCI, CHICAGO, IL 60637 USA. BROOKHAVEN NATL LAB, DEPT APPL SCI, UPTON, NY 11973 USA. RP BERTSCH, PM (reprint author), UNIV GEORGIA, SAVANNAH RIVER ECOL LAB, DIV BIOGEOCHEM, DRAWER E, AIKEN, SC 29802 USA. RI Bajt, Sasa/G-2228-2010 NR 26 TC 111 Z9 111 U1 5 U2 21 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0013-936X J9 ENVIRON SCI TECHNOL JI Environ. Sci. Technol. PD MAY PY 1994 VL 28 IS 5 BP 980 EP 984 DI 10.1021/es00054a034 PG 5 WC Engineering, Environmental; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA NJ324 UT WOS:A1994NJ32400038 PM 22191844 ER PT J AU FEINENDEGEN, LE AF FEINENDEGEN, LE TI IODOHEPTADECANOIC ACID SCINTIGRAPHY IS RELATED TO LIPID TURNOVER SO EUROPEAN JOURNAL OF NUCLEAR MEDICINE LA English DT Letter RP FEINENDEGEN, LE (reprint author), ASSOC UNIV INC,BROOKHAVEN NATL LAB,DEPT MED,POB 5000,UPTON,NY 11973, USA. NR 2 TC 0 Z9 0 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0340-6997 J9 EUR J NUCL MED JI Eur. J. Nucl. Med. PD MAY PY 1994 VL 21 IS 5 BP 467 EP 468 PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NL212 UT WOS:A1994NL21200016 PM 8062855 ER PT J AU DIMRI, GP CAMPISI, J AF DIMRI, GP CAMPISI, J TI ALTERED PROFILE OF TRANSCRIPTION FACTOR-BINDING ACTIVITIES IN SENESCENT HUMAN FIBROBLASTS SO EXPERIMENTAL CELL RESEARCH LA English DT Article ID RETINOBLASTOMA GENE-PRODUCT; RNA POLYMERASE-II; REPLICATIVE SENESCENCE; DNA-SYNTHESIS; CYCLIC-AMP; AP-1 ACTIVITY; HUMAN-CELLS; C-FOS; EXPRESSION; PROTEIN AB Normal eukaryotic cells divide a limited number of times, after which they enter a state of irreversible growth arrest and altered function termed senescence. Cell senescence entails changes in the expression of growth- and differentiation-specific genes, suggesting that senescent cells express an altered profile of transcription factors. Nuclear extracts were prepared from presenescent (quiescent and growing) and senescent human fibroblasts (WI-38) and from SV40-immortalized WI-38 cells and Y79 human retinoblastoma tumor cells-both of which have escaped senescence. The extracts were assayed for ability to form specific protein-DNA complexes with oligonucleotides containing binding sites for the general transcription factors CTF (CAAT-binding transcription factor), SP1 (promotor-specific transcription factor-1), and TFIID (transcription factor-IID) and the more gene-specific factors AP1 (activator protein factor-1), CREBP (cAMP response element-binding protein), GREBP (glucocorticoid response element-binding protein), NF-kappa B (nuclear factor kappa B) and OctBP (octamer-binding protein). Two TFIID complexes and the GREBP, NP-kappa B, and SP1 complexes were similar in presenescent and senescent cells. AP1, CREBP, and CTF complexes were reduced in senescent cells. Two activities were more abundant in senescent cells: OctBP and one TFIID complex. This TFIID complex was present in quiescent cells, but absent from four human cell lines that lack a functional retinoblastoma protein (pRb); both pRb-specific and TFIID-specific antibodies selectively disrupted it. The data suggest that an altered profile of transcription factors may specify the senescent phenotype and that pRb may interact with TFIID or a TFIID-associated protein(s). (C) 1994 Academic Press, Inc. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DEPT CELL & MOLEC BIOL,BERKELEY,CA 94720. FU NIA NIH HHS [AG09909] NR 54 TC 56 Z9 56 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0014-4827 J9 EXP CELL RES JI Exp. Cell Res. PD MAY PY 1994 VL 212 IS 1 BP 132 EP 140 DI 10.1006/excr.1994.1127 PG 9 WC Oncology; Cell Biology SC Oncology; Cell Biology GA NL213 UT WOS:A1994NL21300017 PM 8174635 ER PT J AU GANG, FY SIGMAR, DJ LEBOEUF, JN WISING, F AF GANG, FY SIGMAR, DJ LEBOEUF, JN WISING, F TI ALPHA-PARTICLE-DRIVEN ALFVEN TURBULENCE AND ITS EFFECT ON ALPHA-PARTICLE TRANSPORT SO FUSION TECHNOLOGY LA English DT Article; Proceedings Paper CT 3rd International-Atomic-Energy-Agency Meeting on Alpha-Particle Physics CY MAY 10-15, 1993 CL TRIESTE, ITALY SP INT ATOM ENERGY AGCY DE ALFVEN TURBULENCE; ALPHA-PARTICLE TRANSPORT; POWER COUPLING ID EIGENMODES; TOKAMAKS; PLASMA; WAVES; DESTABILIZATION; EXCITATION; SATURATION AB Recent developments in computational and theoretical studies of alpha-particle-driven Alfven turbulence in both the long (k(perpendicular-to) rho(i) much less than 1) and the short (k (perpendicular-to) rho(i) less-than-or-equal-to 1) wavelength regimes are reported. In the long wavelength regime, a hybrid particle-fluid model is solved numerically as well as analytically in a simple slab geometry. The dominant nonlinear interactions are found to be couplings between two Alfven waves to generate a zero-frequency electromagnetic convective cell and strong E x B convection of resonant alpha particles, which result in significant changes in plasma equilibria. The fluctuation energies first increase, then saturate and decay. The alpha-particle transport is convective and significant but does not necessarily lead to an appreciable alpha-particle loss. A mode-coupling theory is developed to explain the simulation results. In the short wavelength regime, a reduced turbulence model that describes the coupled nonlinear evolutions of fluctuation spectrum \phi\k2 and alpha-particle density profile n(alpha)(r,t) in the presence of an alpha-particle source S(alpha)(r,t) is solved numerically. A steady state is achieved. The nonlinear saturation is due to ion Compton scattering-induced energy transfer to higher wave numbers. Alpha-particle transport is significant, and a diffusion coefficient of D(alpha) congruent-to 0.5 m2/s for International Thermonuclear Experimental Reactor (ITER)-like parameters is obtained. The effect of anomalous alpha-particle diffusion on alpha-particle power coupling to bulk plasmas is also discussed. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37830. CHALMERS UNIV TECHNOL,S-41296 GOTHENBURG,SWEDEN. RP GANG, FY (reprint author), MIT,CTR PLASMA FUS,CAMBRIDGE,MA 02139, USA. NR 21 TC 0 Z9 0 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0748-1896 J9 FUSION TECHNOL JI Fusion Technol. PD MAY PY 1994 VL 25 IS 3 BP 266 EP 277 PG 12 WC Nuclear Science & Technology SC Nuclear Science & Technology GA NH435 UT WOS:A1994NH43500006 ER PT J AU KELLER, H REDDING, JM MOBERG, G DORES, RM AF KELLER, H REDDING, JM MOBERG, G DORES, RM TI ANALYSIS OF THE POSTTRANSLATIONAL PROCESSING OF ALPHA-MSH IN THE PITUITARIES OF THE CHONDROSTEAN FISHES, ACIPENSER-TRANSMONTANUS AND POLYODON SPATHULA SO GENERAL AND COMPARATIVE ENDOCRINOLOGY LA English DT Article ID MELANOCYTE-STIMULATING HORMONE; PEPTIDE ACETYLTRANSFERASE ACTIVITY; BETA-ENDORPHIN; INTERMEDIATE PITUITARY; ANOLIS-CAROLINENSIS; CARBOXYPEPTIDASE-E; RAT PITUITARY; N-ACETYLATION; MELANOTROPIN; LOCALIZATION AB Multiple forms of alpha-MSH were isolated from the pituitaries of the white sturgeon, Acipenser transmontanus, and the paddlefish, Polyodon spathula, following fractionation of the pituitary extracts by reversed-phase HPLC. In both species, immunoreactive forms which eluted with the same retention times as synthetic mammalian ACTH(1-13)NH2, monoacetylated alpha-MSH, and diacetylated alpha-MSH were detected. In the pituitary of the sturgeon, N-acetylated forms of alpha-MSH represented 91% of the total alpha-MSK isolated. However, in the pituitary of the paddlefish, N-acetylated forms of alpha-MSH accounted for only 45% of the total alpha-MSH isolated. The presence of N-acetylated forms of (a)lpha-MSH in the pituitaries of representatives of the two extant genera of chondrostean fish coupled with the observation that N-acetylated forms of alpha-MSH are present in the pituitaries of cladistian and neopterygian fishes indicates that the alpha-MSH specific N-acetylation mechanism evolved prior to the radiation of the Actinopterygii. A conspicuous feature of the chondrostean alpha-MSH N-acetylation reaction was the low levels of diacetylated alpha-MSH produced relative to the levels of monoacetylated alpha-MSH. Similar observations have been made for the cladistian fish, Calamoichthys calaburicus, and the cartilaginous fish, Hydrolagus colliei. However, in holostean fishes, lungfishes, and tetrapods, the diacetylated form of alpha-MSH is the major end product produced in the intermediate pituitary. The phylogenetic implications of these observations will be discussed. (C) 1994 Academic Press, Inc. C1 UNIV DENVER,DEPT BIOL SCI,DENVER,CO 80208. TENNESSEE TECHNOL UNIV,DEPT BIOL,COOKEVILLE,TN 38505. LAWRENCE LIVERMORE NATL LAB,AQUACULTURE & FISHERIES PROGRAM,DAVIS,CA 95616. NR 29 TC 12 Z9 12 U1 0 U2 0 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0016-6480 J9 GEN COMP ENDOCR JI Gen. Comp. Endocrinol. PD MAY PY 1994 VL 94 IS 2 BP 159 EP 165 DI 10.1006/gcen.1994.1071 PG 7 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA NP157 UT WOS:A1994NP15700001 PM 7926625 ER PT J AU KOUPRINA, N ELDAROV, M MOYZIS, R RESNICK, M LARIONOV, V AF KOUPRINA, N ELDAROV, M MOYZIS, R RESNICK, M LARIONOV, V TI A MODEL SYSTEM TO ASSESS THE INTEGRITY OF MAMMALIAN YACS DURING TRANSFORMATION AND PROPAGATION IN YEAST SO GENOMICS LA English DT Article ID ARTIFICIAL CHROMOSOME LIBRARY; SEQUENCE-TAGGED SITES; CARRYING HUMAN DNA; SACCHAROMYCES-CEREVISIAE; HUMAN GENOME; MITOTIC RECOMBINATION; GENETIC-CONTROL; X-CHROMOSOME; CONSTRUCTION; CLONES AB Yeast artificial chromosomes (YACs) containing mammalian DNA potentially can undergo deletions during transformation and propagation, possibly due to interactions between repeat DNAs. To study factors involved in such rearrangements, we developed a genetic system that can signal physical changes. An Alu-HIS3-Alu cassette has been targeted to a mitotically stable YAC containing a 360-kb DNA insert of human chromosome 2. Five YACs with the cassette integrated at different positions were examined for loss of the internal HIS3 marker during transformation into yeast and subsequent growth. The average frequency of the internal marker loss in mitotically growing cells was approximately 1.0 x 10(-4). Physical analysis of His(-) YACs retaining both telomeric markers demonstrated that loss of the marker was due to deletions (20-90 kb). These results contrast with those obtained with YACs following transformation. Nearly 33% of the retransformed YACs lacked the internal HIS3 marker. The transformation-associated loss was also due to deletions varying from 80 to 260 kb. Similar results were obtained following retransformation with the parent human YAC and another mitotically stable YAC containing a 390-kb insert of mouse DNA The high level of transformation-associated deletions in the human YACs was reduced over 10-fold when the host was a recombination-deficient strain deleted for the RAD52 gene. The level of internal human YAC instability during mitotic growth was also significantly decreased in the rad52 mutant strain compared to that in the isogenic Rad(+) strain. However, retransformation of the rad52 mutant with a YAC-containing mouse DNA yielded comparable levels of alterations to those observed for the wildtype strain. Thus, there must be additional genetic factors involved in transformation-associated deletions in YACs. We propose that these YACs and strains can be useful tools for investigating YAC integrity. During the course of these studies a unique category of deletions was identified in mitotically propagated YACs that result from recombination between identical sequences in the telomeric region and the HIS3 cassette. In addition to the known YAC ''fragmentation'' method, this may provide a means for generating internal deletions as well as an alternative method for mapping. (C) 1994 Academic Press, Inc. C1 NIEHS,MOLEC GENET LAB,RES TRIANGLE PK,NC 27709. RUSSIAN ACAD SCI,INST CYTOL,ST PETERSBURG 194064,RUSSIA. CTR BIOENGN,MOSCOW 117984,RUSSIA. LOS ALAMOS NATL LAB,CTR HUMAN GENOME STUDIES,LOS ALAMOS,NM 87545. FU NHGRI NIH HHS [1-YO2-HG-60021-01] NR 68 TC 42 Z9 43 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD MAY 1 PY 1994 VL 21 IS 1 BP 7 EP 17 DI 10.1006/geno.1994.1218 PG 11 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA NL712 UT WOS:A1994NL71200002 PM 8088818 ER PT J AU MARRONE, BL CAMPBELL, EW ANZICK, SL SHERA, K CAMPBELL, M YOSHIDA, TM MCCORMICK, MK DEAVEN, L AF MARRONE, BL CAMPBELL, EW ANZICK, SL SHERA, K CAMPBELL, M YOSHIDA, TM MCCORMICK, MK DEAVEN, L TI MAPPING OF LOW-FREQUENCY CHIMERIC YEAST ARTIFICIAL CHROMOSOME LIBRARIES FROM HUMAN CHROMOSOME-16 AND CHROMOSOME-21 BY FLUORESCENCE IN-SITU HYBRIDIZATION AND QUANTITATIVE IMAGE-ANALYSIS SO GENOMICS LA English DT Article ID INSITU HYBRIDIZATION; COSMID CLONES; YAC AB Yeast artificial chromosome (YAC) clones from low-frequency chimeric libraries of human chromosomes 16 and 21 were mapped onto human diploid fibroblast metaphase chromosomes using fluorescence in situ hybridization (FISH) and digital imaging microscopy. YACs mapped onto chromosome 21 were selected to provide subregional location and ordering of known and unknown markers on the long arm of chromosome 21, particularly in the Down syndrome region (q22). YACs mapped onto chromosome 16 were selected to overlap regions spanning chromosome 16 cosmid maps. YAC clones were indirectly labeled with fluorescein, and the total DNA of the chromosome was counterstained with propidium iodide. A single image containing both the FISH signal and the whole chromosome was acquired for each chromosome of interest containing the fluorescent probe signal in a metaphase spread. From the digitized image, the fluorescence intensity profile through the long axis of the chromosome gave the total chromosome length and the probe position. The map position of the probe was expressed as the fractional length (FL) of the total chromosome relative to the end of the short arm (FLpter). From each clone hybridized, 20-40 chromosome images were analyzed. Thirty-eight YACs were mapped onto chromosome 16, and their FLs were distributed along the short and long arms. On chromosome 21, 47 YACs were mapped, including 12 containing known markers. To confirm the order of a dense population of YACs within the Down syndrome region, a two-color mapping strategy was used in which an anonymous YAC was located relative to one or two known markers on the metaphase chromosome. Our chromosome FL maps have a 1- to 2-Mb resolution, and the FL measurement of each probe has a typical standard error of 0.5- 1 Mb. (C) 1994 Academic Press, Inc. C1 LOS ALAMOS NATL LAB,CTR HUMAN GENOME STUDIES,LOS ALAMOS,NM 87545. RP MARRONE, BL (reprint author), LOS ALAMOS NATL LAB,DIV LIFE SCI,LS-1,M888,LOS ALAMOS,NM 87545, USA. FU NCRR NIH HHS [P41-RR01315] NR 14 TC 4 Z9 4 U1 0 U2 2 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD MAY 1 PY 1994 VL 21 IS 1 BP 202 EP 207 DI 10.1006/geno.1994.1243 PG 6 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA NL712 UT WOS:A1994NL71200027 PM 8088788 ER PT J AU MARSHALL, WL AF MARSHALL, WL TI HYDROTHERMAL SYNTHESIS OF AMINO-ACIDS SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article ID HIGH-TEMPERATURE; HOT-SPRINGS; LIFE; ORIGIN; BIOMOLECULES; STABILITY AB This study presents further evidence that amino acids can be synthesized rapidly in hydrothermal solutions from reactants that may have been present in primitive environments. Aqueous NH4HCO3 solutions were reacted with C2H2, H-2, and O2 (formed in situ from CaC2, Ca, and H2O2) at 200-275-degrees-C over 0.2-2 h periods to synthesize several amino acids and abundant amines. These amino acid and amine producing reactions were not observed to occur below 150-degrees-C. Amino acids and amines also were synthesized at 210-degrees-C from solutions of NH4OH, HCHO, NaCN, and H-2. When NH4OH was replaced by NH4HCO3, the syntheses predominantly confirmed the recent results of HENNET et al. (1992). Additionally, amino acids and amines were observed to form by reactions among NH4OH, HCHO, and H-2 at hydrothermal conditions, essentially confirming the results of Fox and WINDSOR (1970). Inclusion of both carbonate and O2 in these latter solutions greatly enhanced the production rate of amino acids. The amines synthesized hydrothermally could be significant if they are precursors in the amino acid syntheses either at hydrothermal or later at lower temperatures. These observations provide additional input to the current questions of synthesis, stability, and decomposition of amino acids at hydrothermal conditions, and their possible relevance to the origin of life. RP MARSHALL, WL (reprint author), OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,OAK RIDGE,TN 37831, USA. NR 48 TC 91 Z9 93 U1 6 U2 23 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD MAY PY 1994 VL 58 IS 9 BP 2099 EP 2106 DI 10.1016/0016-7037(94)90288-7 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA NN137 UT WOS:A1994NN13700009 ER PT J AU GUIDOTTI, CV SASSI, FP BLENCOE, JG SELVERSTONE, J AF GUIDOTTI, CV SASSI, FP BLENCOE, JG SELVERSTONE, J TI THE PARAGONITE-MUSCOVITE SOLVUS .1. P-T-X LIMITS DERIVED FROM THE NA-K COMPOSITIONS OF NATURAL, QUASI-BINARY PARAGONITE-MUSCOVITE PAIRS SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT Symposium in Honor of Heinrich D Holland CY MAY 08-09, 1992 CL RESTON, VA ID CRYSTALLINE SOLUTIONS; ALPINE METAMORPHISM; MIXING PROPERTIES; HIGH-TEMPERATURES; SOUTHWEST TURKEY; CELL DIMENSIONS; TAUERN WINDOW; 2M1 MUSCOVITE; EQUILIBRIA; SYSTEM AB Data on the Na-K compositions and final equilibration temperatures of natural, quasibinary paragonite-muscovite (Pg-Ms) pairs (mole fraction of margarite in Pg < 0.05; Si/formula unit less-than-or-equal-to 6.2 and/or SIGMA(Mg + Fe2+ + Fe3+) less-than-or-equal-to 0.35 for Ms) have been plotted and analyzed to determine the P - T - X limits of the binary Pg-Ms solvus. There is considerable scatter in the data, but the T-X morphology of the solvus is clearly discernible. Scatter in the data can be attributed to numerous potential sources of error, including (1) inaccuracies in determinations of the Na-K compositions of the coexisting micas, (2) H3O+ --> K+ and vacancy --> K+ substitution in Ms and/or Pg, and (3) crystallization and preservation of quasibinary Pg-Ms pairs with metastable Na-K compositions. Data on the Na-K compositions of both Pg and Ms are available for twenty-eight of the Pg-Ms pairs examined in this report. This subset of data was used to develop parametric equations for an average (pressure-independent), binary Pg-Ms solvus. In accordance with results obtained by previous investigators, the new solvus is strongly asymmetric toward paragonite, and the Ms limb has a shallower slope than the Pg limb. However, calculated solvus critical constants (critical temperature = 796.5-degrees-C; critical composition = 34.1 mol% muscovite) are significantly different from corresponding values obtained from published thermodynamic models for binary Pg-Ms micas. C1 UNIV PADUA,DIPARTIMENTO MINERAL & PETROL,I-35100 PADUA,ITALY. UNIV COLORADO,DEPT GEOL SCI,BOULDER,CO 80309. OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,OAK RIDGE,TN 37831. RP GUIDOTTI, CV (reprint author), UNIV MAINE,DEPT GEOL SCI,ORONO,ME 04469, USA. RI Selverstone, Jane/A-9809-2008 OI Selverstone, Jane/0000-0003-4234-4111 NR 46 TC 35 Z9 35 U1 0 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD MAY PY 1994 VL 58 IS 10 BP 2269 EP 2275 DI 10.1016/0016-7037(94)90009-4 PG 7 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA NQ012 UT WOS:A1994NQ01200009 ER PT J AU BLENCOE, JG GUIDOTTI, CV SASSI, FP AF BLENCOE, JG GUIDOTTI, CV SASSI, FP TI THE PARAGONITE-MUSCOVITE SOLVUS .2. NUMERICAL GEOTHERMOMETERS FOR NATURAL, QUASI-BINARY PARAGONITE-MUSCOVITE PAIRS SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT Symposium in Honor of Heinrich D Holland CY MAY 08-09, 1992 CL RESTON, VA ID CRYSTALLINE SOLUTIONS; MIXING PROPERTIES AB Three parametric (nonthermodynamic) equations have been developed to calculate final equilibration temperatures for natural, quasibinary paragonite-muscovite (Pg-Ms) pairs (mole fraction margarite in Pg < 0.05, Si/formula unit less-than-or-equal-to 6.2 and/or SIGMA (Mg + Fe2+ + Fe3+) less-than-or-equal-to 0.35 for coexistent Ms). The first two equations are paragonite-based and muscovite-based, because they yield equilibration temperatures that depend on the Na-K compositions of K-saturated Pg and Na-saturated Ms, respectively. The third equation is closure-based, because it yields equilibration temperatures that vary with the width of the pp between the Na-K compositions of coexisting Pg and Ms (i.e., the degree of solvus closure). Equilibration temperatures can be estimated, using just one of the geothermometers, or by averaging the temperatures obtained from any combination of the three equations. Comparison of the three calculated temperatures yields information on the mutual consistencies of the Na-K compositions of coexisting Pg and Ms with respect to their utility in Pg-Ms solvus thermometry. Geothermometric inconsistencies in the Na-K compositions of quasibinary Pg-Ms pairs can be caused by (1) inaccuracies in determinations of the Na-K compositions of the coexisting micas, (2) H3O+ --> K+ and vacancy --> K+ substitution in muscovite and/or paragonite, and (3) crystallization and preservation of quasibinary Pg-Ms pairs with metastable Na-K compositions. Due to the effects of pressure on the stability relations of Pg-Ms pairs and the K/Na ratios of Na-saturated muscovites, practical applications of Pg-Ms solvus thermometry are restricted to quasibinary Pg-Ms pairs that equilibrated at pressures between approximately 2 and 8 kbar. Within this pressure range, the utility of Pg-Ms solvus thermometry is limited thermally to approximately 300 less-than-or-equal-to T less-than-or-equal-to 700-degrees-C by (1) the decomposition of K-saturated paragonite at temperatures between approximately 580 and 700-degrees-C, and (2) steepening of the solvus limbs at temperatures below 300-degrees-C. Graphical and calculated Pg-Ms solvi based on solvus data for synthetic, binary Pg-Ms micas are inconsistent with solvus data for natural, quasibinary Pg-Ms micas. Consequently, these solvi should not be used to estimate equilibration temperatures for natural, quasibinary Pg-Ms pairs. C1 UNIV MAINE,DEPT GEOL SCI,ORONO,ME 04469. UNIV PADUA,DIPARTIMENTO MINERAL & PETROL,I-35100 PADUA,ITALY. RP BLENCOE, JG (reprint author), OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,OAK RIDGE,TN 37831, USA. NR 20 TC 30 Z9 30 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD MAY PY 1994 VL 58 IS 10 BP 2277 EP 2288 DI 10.1016/0016-7037(94)90010-8 PG 12 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA NQ012 UT WOS:A1994NQ01200010 ER PT J AU SIEGEL, MD ANDERHOLM, S AF SIEGEL, MD ANDERHOLM, S TI GEOCHEMICAL EVOLUTION OF GROUNDWATER IN THE CULEBRA DOLOMITE NEAR THE WASTE ISOLATION PILOT-PLANT, SOUTHEASTERN NEW-MEXICO, USA SO GEOCHIMICA ET COSMOCHIMICA ACTA LA English DT Article; Proceedings Paper CT Symposium in Honor of Heinrich D Holland CY MAY 08-09, 1992 CL RESTON, VA ID MINERAL SOLUBILITIES; OSMOTIC COEFFICIENTS; NATURAL-WATERS; CLAY-MINERALS; THERMODYNAMICS; ELECTROLYTES; 25-DEGREES-C; PREDICTION; SYSTEM; BORON AB The Culebra Dolomite Member of the Rustler Formation, a thin (10 m) fractured dolomite aquifer, lies approximately 450 m above the repository horizon of the Waste Isolation Pilot Plant (WIPP) in southeastern New Mexico, USA. Salinities of water in the Culebra range roughly from 10,000 to 200,000 mg/ L within the WIPP site. A proposed model for the post-Pleistocene hydrochemical evolution of the Culebra tentatively identifies the major sources and sinks for many of the groundwater solutes. Reaction-path simulations with the PHRQPITZ code suggest that the Culebra dolomite is a partial chemical equilibrium system whose composition is controlled by an irreversible process (dissolution of evaporites) and equilibrium with gypsum and calcite. Net geochemical reactions along postulated modern flow paths, calculated with the NETPATH code, include dissolution of halite, carbonate and evaporite salts, and ion exchange. R-mode principal component analysis revealed correlations among the concentrations of Si, Mg, pH, Li, and B that are consistent with several clay-water reactions. The results of the geochemical calculations and mineralogical data are consistent with the following hydrochemical model: (1) solutes are added to the Culebra by dissolution of evaporite minerals; (2) the solubilities of gypsum and calcite increase as the salinity increases; these minerals dissolve as chemical equilibrium is maintained between them and the groundwater; (3) equilibrium is not maintained between the waters and dolomite; sufficient Mg is added to the waters by dissolution of accessory carnallite or polyhalite such that the degree of dolomite supersaturation increases with ionic strength; and (4) clays within the fractures and rock matrix exert some control on the distribution of Li, B, Mg, and Si via sorption, ion exchange, and dissolution. C1 US GEOL SURVEY,DIV WATER RESOURCES,ALBUQUERQUE,NM 87110. RP SIEGEL, MD (reprint author), SANDIA NATL LABS,CTR GEOSCI & GEOTECHNOL,ALBUQUERQUE,NM 87185, USA. NR 78 TC 10 Z9 10 U1 1 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0016-7037 J9 GEOCHIM COSMOCHIM AC JI Geochim. Cosmochim. Acta PD MAY PY 1994 VL 58 IS 10 BP 2299 EP 2323 DI 10.1016/0016-7037(94)90012-4 PG 25 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA NQ012 UT WOS:A1994NQ01200012 ER PT J AU NIHEI, KT MYER, LR COOK, NGW YI, WD AF NIHEI, KT MYER, LR COOK, NGW YI, WD TI EFFECTS OF NONWELDED INTERFACES ON GUIDED SH-WAVES SO GEOPHYSICAL RESEARCH LETTERS LA English DT Article ID SEISMIC-WAVES; TRANSMISSION; FRACTURE AB The effects of non-welded interfaces on guided SH-waves are examined analytically and numerically using the displacement-discontinuity model to describe the mechanical shear stiffnesses of the interfaces. A modal solution for guided SH-waves is developed for a layer in non-welded contact with underlying and overlying half-spaces. For low interface stiffnesses, the modal solution degenerates to the SH-plate wave solution and for high interface stiffnesses, to the Love channel wave solution. It is demonstrated that a single non-welded interface separating two half-spaces is incapable of supporting an SH-interface wave. The effects of interface stiffness on the phase velocities and displacement profiles of guided SH-waves are examined for a low velocity layer in non-welded contact with bounding half-spaces using the modal solution and a numerical boundary integral equation code. The results of this analysis demonstrate that the magnitude of the interface stiffness can have a first order effect on the velocities, amplitudes and displacement profiles of guided SH-waves in a low velocity layer which should make these waves highly detectable in crosshole seismic surveys. C1 UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720. RP NIHEI, KT (reprint author), LAWRENCE BERKELEY LAB,DIV EARTH SCI,1 CYCLOTRON RD,50E,BERKELEY,CA 94720, USA. RI Nihei, Kurt/K-1239-2016 NR 14 TC 11 Z9 11 U1 1 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0094-8276 J9 GEOPHYS RES LETT JI Geophys. Res. Lett. PD MAY 1 PY 1994 VL 21 IS 9 BP 745 EP 748 DI 10.1029/94GL00365 PG 4 WC Geosciences, Multidisciplinary SC Geology GA NK051 UT WOS:A1994NK05100001 ER PT J AU BURTON, JC AF BURTON, JC TI EXPEDITED SITE CHARACTERIZATION PROCESS CAN LEAD TO FASTER, LESS COSTLY CLEANUPS SO HAZARDOUS WASTE CONSULTANT LA English DT Article RP BURTON, JC (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0738-0232 J9 HAZARDOUS WASTE CONS JI Hazard. Waste Consult. PD MAY-JUN PY 1994 VL 12 IS 3 BP A7 EP A10 PG 4 WC Engineering, Environmental SC Engineering GA NM860 UT WOS:A1994NM86000003 ER PT J AU CHEN, CJ WENG, PS CHU, TC KNUTSON, EO AF CHEN, CJ WENG, PS CHU, TC KNUTSON, EO TI DISCRIMINATION OF AIRBORNE RADIOACTIVITY FROM RADON PROGENY SO HEALTH PHYSICS LA English DT Article DE RADON; RADON PROGENY; RADIOACTIVITY; AEROSOLS AB Naturally occurring radon and thoron progeny are the most interfering nuclides in the aerosol monitoring system. The high background and fluctuation of natural radioactivity on the filter can cause an error message to the aerosol monitor. A theoretical model was applied in the simulation of radon and thoron progeny behavior in the environment and on the filter. Results show that even a small amount of airborne nuclides on the filter could be discriminated by using the beta:alpha activity ratio instead of gross beta or alpha counting. This method can increase the sensitivity and reliability of real-time aerosol monitoring. C1 US DOE, ENVIRONM MEASUREMENTS LAB, NEW YORK, NY 10014 USA. RP CHEN, CJ (reprint author), NATL TSING HUA UNIV, INST NUCL SCI, HSINCHU 300, TAIWAN. NR 8 TC 1 Z9 3 U1 0 U2 1 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 530 WALNUT ST, PHILADELPHIA, PA 19106-3621 USA SN 0017-9078 EI 1538-5159 J9 HEALTH PHYS JI Health Phys. PD MAY PY 1994 VL 66 IS 5 BP 557 EP 564 DI 10.1097/00004032-199405000-00008 PG 8 WC Environmental Sciences; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA NF707 UT WOS:A1994NF70700008 PM 8175363 ER PT J AU CHESSHIRE, G NAIK, VK AF CHESSHIRE, G NAIK, VK TI AN ENVIRONMENT FOR PARALLEL AND DISTRIBUTED COMPUTATION WITH APPLICATION TO OVERLAPPING GRIDS SO IBM JOURNAL OF RESEARCH AND DEVELOPMENT LA English DT Article AB We describe an environment for efficient and scalable implementation of large scientific applications on parallel and distributed computing systems. We show how this environment is used to support overlapping grid methods. In addition to providing a user interface that reduces programming complexity, the environment facilitates dynamic partitioning of data and the scheduling of both computations and communication, transparent to the user. After describing the user interface and some of the implementation issues, we present performance data for a model application executed on two different systems: an eight-processor IBM Power Parallel Prototype (PPP) system and a 32-processor IBM POWER Visualization System(TM) (PVS). C1 IBM CORP,THOMAS J WATSON RES CTR,DIV RES,PARALLEL APPLICAT METHODS & ANAL GRP,YORKTOWN HTS,NY 10598. RP CHESSHIRE, G (reprint author), LOS ALAMOS NATL LAB,COMP RES & APPLICAT GRP,LOS ALAMOS,NM 87545, USA. NR 14 TC 1 Z9 1 U1 0 U2 0 PU IBM CORP PI ARMONK PA OLD ORCHARD RD, ARMONK, NY 10504 SN 0018-8646 J9 IBM J RES DEV JI IBM J. Res. Dev. PD MAY PY 1994 VL 38 IS 3 BP 285 EP 300 PG 16 WC Computer Science, Hardware & Architecture; Multidisciplinary Sciences SC Computer Science; Science & Technology - Other Topics GA NV248 UT WOS:A1994NV24800007 ER PT J AU FRIEDMAN, A KRINSKY, S YU, LH AF FRIEDMAN, A KRINSKY, S YU, LH TI FEL GAIN REDUCTION DUE TO WIGGLER ERRORS SO IEEE JOURNAL OF QUANTUM ELECTRONICS LA English DT Article ID FREE-ELECTRON-LASER; PERFORMANCE; REGIME AB We report the results of a study comparing an analytical theory of wiggler errors in free-electron lasers (FEL's) to a numerical simulation. The different mechanisms of reduction in FEL gain due to wiggler errors are reviewed, and in each case analytical results are compared with computer simulation and shown to be in good agreement. We present a study of the proposed UV FEL user facility at BNL and determine the implications of the wiggler errors on the FEL design. RP FRIEDMAN, A (reprint author), BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,POB 5000,UPTON,NY 11973, USA. NR 19 TC 5 Z9 5 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9197 J9 IEEE J QUANTUM ELECT JI IEEE J. Quantum Electron. PD MAY PY 1994 VL 30 IS 5 BP 1295 EP 1302 DI 10.1109/3.303696 PG 8 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA NY698 UT WOS:A1994NY69800024 ER PT J AU THOMAS, VA JONES, ME PIKETMAY, M TAFLOVE, A HARRIGAN, E AF THOMAS, VA JONES, ME PIKETMAY, M TAFLOVE, A HARRIGAN, E TI THE USE OF SPICE LUMPED CIRCUITS AS SUBGRID MODELS FOR FDTD ANALYSIS SO IEEE MICROWAVE AND GUIDED WAVE LETTERS LA English DT Article AB A general approach for including lumped circuit elements in a finite difference, time domain (FDTD) solution of Maxwell's equations is presented. The methodology allows the direct access to SPICE to model the lumped circuits, while the full 3-Dimensional solution to Maxwell's equations provides the crosstalk and dispersive properties of the microstrips and striplines in the circuit. RP THOMAS, VA (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Taflove, Allen/B-7275-2009 NR 0 TC 86 Z9 89 U1 0 U2 2 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1051-8207 J9 IEEE MICROW GUIDED W JI IEEE Microw. Guided Wave Lett. PD MAY PY 1994 VL 4 IS 5 BP 141 EP 143 DI 10.1109/75.289516 PG 3 WC Engineering, Electrical & Electronic SC Engineering GA NQ021 UT WOS:A1994NQ02100005 ER PT J AU SHARMA, AK SCOTT, KAM BRUECK, SRJ ZOLPER, JC MYERS, DR AF SHARMA, AK SCOTT, KAM BRUECK, SRJ ZOLPER, JC MYERS, DR TI ION-IMPLANTATION ENHANCED METAL-SI-METAL PHOTODETECTORS SO IEEE PHOTONICS TECHNOLOGY LETTERS LA English DT Article AB The quantum efficiency and frequency response of simple Ni-Si-Ni metal-semiconductor-metal (MSM) photodetectors at long wavelengths are significantly enhanced with a simple, ion-implantation step to create a highly absorbing region approximately 1 mum below the Si surface. The internal quantum efficiency is improved by a factor of approximately 3 at 860 nm (to 64%) and a full factor of ten at 1.06 mum (to 23%) as compared with otherwise identical unimplanted devices. Dark currents are only slightly affected by the implantation process and are as low as 630 pA for a 4.5-mum gap device at 10-V bias. Dramatic improvement in the impulse response is observed, 100 ps vs. 600 ps, also at 10-V bias and 4.5-mum gap, due to the elimination of carrier diffusion tails in the implanted devices. Due to its planar structure, this device is fully VLSI compatible. Potential applications include optical interconnections for local area networks and multi-chip modules. C1 UNIV NEW MEXICO,DEPT ELECT & COMP ENGN,ALBUQUERQUE,NM 87131. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. UNIV NEW MEXICO,DEPT PHYS & ASTRON,ALBUQUERQUE,NM 87131. RP SHARMA, AK (reprint author), UNIV NEW MEXICO,CTR HIGH TECHNOL MAT,ALBUQUERQUE,NM 87131, USA. RI Brueck, Steven/A-6383-2013; OI Brueck, Steven/0000-0001-8754-5633 NR 7 TC 15 Z9 15 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 1041-1135 J9 IEEE PHOTONIC TECH L JI IEEE Photonics Technol. Lett. PD MAY PY 1994 VL 6 IS 5 BP 635 EP 638 DI 10.1109/68.285564 PG 4 WC Engineering, Electrical & Electronic; Optics; Physics, Applied SC Engineering; Optics; Physics GA NL837 UT WOS:A1994NL83700016 ER PT J AU WARNE, LK CHEN, KC AF WARNE, LK CHEN, KC TI A BOUND ON APERTURE COUPLING FROM REALISTIC EMP SO IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY LA English DT Note AB Rigorous modification of the step function electromagnetic pulse (EMP) energy bound, for apertures, to the more realistic description of an EMP waveform is carried out. The double exponential EMP waveform is used first and a general formula is derived for the energy scattered and absorbed by the aperture. This result shows that for very small apertures the energy can be quite small compared to the previous step function result. However, it is indicated that, in principle, if no further conditions are imposed on the structures behind the aperture (or attached to the aperture), the smallest applicable bound is the previous step function bound. Finally, the inverse exponential EMP waveform (with more realistic high-frequency spectrum) is used with very small apertures to obtain even smaller energy bounds than the double exponential waveform result. RP WARNE, LK (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 13 TC 3 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9375 J9 IEEE T ELECTROMAGN C JI IEEE Trans. Electromagn. Compat. PD MAY PY 1994 VL 36 IS 2 BP 149 EP 154 DI 10.1109/15.293273 PG 6 WC Engineering, Electrical & Electronic; Telecommunications SC Engineering; Telecommunications GA NL833 UT WOS:A1994NL83300012 ER PT J AU MORRIS, ME FISHER, RJ SCHNETZER, GH MEREWETHER, KO JORGENSON, RE AF MORRIS, ME FISHER, RJ SCHNETZER, GH MEREWETHER, KO JORGENSON, RE TI ROCKET-TRIGGERED LIGHTNING STUDIES FOR THE PROTECTION OF CRITICAL ASSETS SO IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS LA English DT Article AB Lightning protection systems (LPS's) for explosives handling and storage facilities have long been designed similarly to those used for more conventional facilities, but their overall effectiveness in controlling interior electromagnetic (EM) environments has still not been rigorously assessed. Frequent lightning-caused failures of a security system installed in earth-covered explosives storage structures prompted the U.S. Army and Sandia National Laboratories to conduct a program to determine quantitatively the EM environments inside an explosives storage structure that is struck by lightning. These environments were measured directly during rocket-triggered lightning (RTL) tests in the summer of 1991 and were computed using linear finite-difference, time-domain (FDTD) EM solvers. The experimental and computational results were first compared in order to validate the code and were then used to construct bounds for interior environments corresponding to severe incident lightning flashes. The code results were also used to develop simple circuit models for the EM field behavior-a process that resulted in a very simple and somewhat surprising physical interpretation of the structure's response that has significant practical and economic implications for design, construction, and maintenance of such facilities. RP MORRIS, ME (reprint author), SANDIA NATL LABS,DEPT ELECTROMAGNET ANAL & TEST,ALBUQUERQUE,NM 87185, USA. NR 8 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0093-9994 J9 IEEE T IND APPL JI IEEE Trans. Ind. Appl. PD MAY-JUN PY 1994 VL 30 IS 3 BP 791 EP 804 DI 10.1109/28.293730 PG 14 WC Engineering, Multidisciplinary; Engineering, Electrical & Electronic SC Engineering GA NW041 UT WOS:A1994NW04100039 ER PT J AU ISKANDER, MF SMITH, RL ANDRADE, AOM KIMREY, H WALSH, LM AF ISKANDER, MF SMITH, RL ANDRADE, AOM KIMREY, H WALSH, LM TI FDTD SIMULATION OF MICROWAVE SINTERING OF CERAMICS IN MULTIMODE CAVITIES SO IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES LA English DT Article ID TIME-DOMAIN METHOD; DIFFERENCE AB Microwave sintering of ceramics in multimode cavities, particularly the use of picket-fence arrangements, has recently received considerable attention. Various types of ceramics have been successfully sintered and, in some cases, a desirable and unique ''microwave effect'' has been observed. At present, various aspects of the sintering process such as preparation of sample sizes and shapes, types of insulations, and the desirability of including a process stimulus such as SiC rods are considered forms of art and highly dependent on human expertise. The simulation of realistic sintering experiments in a multimode cavity may provide an improved understanding of critical parameters involved and allow for the development of guidelines towards the optimization of the sintering process. In this paper, we utilize the FDTD technique to model various geometrical arrangements and material compatibility aspects in multimode microwave cavities and to simulate realistic sintering experiments. The FDTD procedure starts with the simulation of a field distribution in multimode microwave cavities that resembles a set of measured data using liquid crystal sheets. Also included in the simulation is the waveguide feed as well as a ceramic loading plate placed at the base of the cavity. The FDTD simulation thus provides realistic representation of a typical sintering experiment. Aspects that have been successfully simulated include the effects of various types of insulation, the role of SiC rods on the uniformity of the resulting microwave fields, and the possible shielding effects that may result from excessive use of SiC. These results as well as others showing the electromagnetic fields and power-deposition patterns in multiple ceramic samples are presented. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. UNIV UTAH,ENGN CLIN PROGRAM,SALT LAKE CITY,UT 84112. RP ISKANDER, MF (reprint author), UNIV UTAH,DEPT ELECT ENGN,SALT LAKE CITY,UT 84112, USA. NR 11 TC 29 Z9 31 U1 1 U2 8 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9480 J9 IEEE T MICROW THEORY JI IEEE Trans. Microw. Theory Tech. PD MAY PY 1994 VL 42 IS 5 BP 793 EP 800 DI 10.1109/22.293527 PG 8 WC Engineering, Electrical & Electronic SC Engineering GA NU262 UT WOS:A1994NU26200006 ER PT J AU RAO, NSV OBLOW, EM AF RAO, NSV OBLOW, EM TI MAJORITY AND LOCATION-BASED FUSERS FOR SYSTEMS OF PAC CONCEPT LEARNERS SO IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS LA English DT Article DE GENERAL MAJORITY RULE; LOCATION BASED FUSERS; COMPUTATIONAL LEARNABILITY; N-LEARNERS PROBLEM ID LEARNABILITY AB A system of probably and approximately correct learners of Valiant type that infer concepts from a sample is considered. Each learner had been trained by a sample using the methods of minimizing the empirical error, and no examples are available to the fuser. A majority fuser is known to make the composite system better than the best of the learners in terms of normalized confidence (that corresponds to the same precision value). An analysis of general majority fusers is carried out to obtain bounds on actual and expected errors. Conditions under which the r-of-N fuser performs better, in terms of normalized confidence or precision, than best of the individual learners are obtained. For a special class of statistically independent learners, slightly weaker conditions are obtained. Two fusers that use the location information of a test point are proposed, and are shown to be better than a learner with least empirical error. C1 OLD DOMINION UNIV,DEPT COMP SCI,NORFOLK,VA 23508. RP RAO, NSV (reprint author), OAK RIDGE NATL LAB,CTR ENGN SYST ADV RES,INTELIGENT SYST SECT,OAK RIDGE,TN 37831, USA. OI Rao, Nageswara/0000-0002-3408-5941 NR 31 TC 4 Z9 4 U1 0 U2 0 PU IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2394 SN 0018-9472 J9 IEEE T SYST MAN CYB JI IEEE Trans. Syst. Man Cybern. PD MAY PY 1994 VL 24 IS 5 BP 713 EP 727 DI 10.1109/21.293485 PG 15 WC Computer Science, Cybernetics; Engineering, Electrical & Electronic SC Computer Science; Engineering GA NU554 UT WOS:A1994NU55400001 ER PT J AU HALLER, GM WOOLEY, BA AF HALLER, GM WOOLEY, BA TI A 700-MHZ SWITCHED-CAPACITOR ANALOG WAVE-FORM SAMPLING CIRCUIT SO IEICE TRANSACTIONS ON ELECTRONICS LA English DT Article AB Analog switched-capacitor memory circuits are suitable for use in a wide range of applications where analog waveforms must be captured or delayed, such as the recording of pulse echo events and pulse shapes. Analog sampling systems based on switched-capacitor techniques offer performance superior to that of flash A/D converters and charge-coupled devices with respect to cost, density, dynamic range, sampling speed, and power consumption. This paper proposes an architecture with which sampling frequencies of several hundred megahertz can be achieved using conventional CMOS technology. Issues concerning the design and implementation of an analog memory circuit based on the proposed architecture are presented. An experimental two-channel memory with 32 sampling cells in each channel has been integrated in a 2-mum CMOS technology with poly-to-poly capacitors. The measured nonlinearity of this prototype is 0.03% for a 2.5 V input range, and the memory cell gain matching is 0.01 % rms. The dynamic range of the memory exceeds 12 b for a sampling frequency of 700 MHz. The power dissipation for one channel operated from a single +5 V supply is 2 mW. RP HALLER, GM (reprint author), STANFORD UNIV, STANFORD LINEAR ACCELERATOR CTR, LINEAR COLLIDER DETECTOR PROJECT, STANFORD, CA 94305 USA. NR 0 TC 1 Z9 1 U1 0 U2 0 PU IEICE-INST ELECTRONICS INFORMATION COMMUNICATIONS ENG PI TOKYO PA KIKAI-SHINKO-KAIKAN BLDG, 3-5-8, SHIBA-KOEN, MINATO-KU, TOKYO, 105-0011, JAPAN SN 0916-8524 EI 1745-1353 J9 IEICE T ELECTRON JI IEICE Trans. Electron. PD MAY PY 1994 VL E77C IS 5 BP 830 EP 838 PG 9 WC Engineering, Electrical & Electronic SC Engineering GA NN910 UT WOS:A1994NN91000029 ER PT J AU SCOTT, TC DEPAOLI, DW SISSON, WG AF SCOTT, TC DEPAOLI, DW SISSON, WG TI FURTHER DEVELOPMENT OF THE ELECTRICALLY DRIVEN EMULSION-PHASE CONTACTOR SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID SOLVENT-EXTRACTION; HEAT-TRANSFER; DROPS; FIELD; OSCILLATION; DROPLETS AB Design developments for the emulsion-phase contactor, including a two-electrode region and modulated electrical signals, have increased throughput such that the technology may be considered for industrial solvent extraction applications. Testing has been conducted to evaluate energy consumption, axial dispersion, and mass transport in lab-scale devices. Energy consumption on a volume basis was measured to be 2.4 W/L, which is several orders of magnitude less than that of conventional liquid-liquid contactors. A moderate amount of axial dispersion was measured, partly due to the open architecture and partly due to wall and end effects of the small experimental devices. Multistage mass transfer was demonstrated in a contactor with a 45-cm electrode height for the system of cupric ion transferring from an aqueous buffer solution to kerosene containing versatic acid. Mass transfer performance of up to four equivalent stages approached the limitations set by the hydrodynamics. RP SCOTT, TC (reprint author), OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831, USA. NR 22 TC 14 Z9 14 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAY PY 1994 VL 33 IS 5 BP 1237 EP 1244 DI 10.1021/ie00029a020 PG 8 WC Engineering, Chemical SC Engineering GA NK617 UT WOS:A1994NK61700020 ER PT J AU LEE, JH VANBRUNT, V KING, CJ AF LEE, JH VANBRUNT, V KING, CJ TI WATER-ENHANCED SOLVATION OF ORGANIC SOLUTES IN KETONE AND ESTER SOLVENTS SO INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH LA English DT Article ID EXTRACTION AB Previous research has shown that the solubilities of dicarboxylic acids in certain electron-donor solvents are substantially increased in the presence of water. Information on solubilities, liquid-liquid equilibria and maximum-boiling ternary azeotropes was screened so as to identify other systems where codissolved water appears to enhance solvation of organic solutes in solvents. Several carboxylic acids, an alcohol, diols, and phenols were selected for examination as solutes in ketone and ester solvents. Effects of water upon solute solubilities and volatilities were measured. Results showed that water-enhanced solvation is greatest for carboxylic acids. Solute activity coefficients decreased by factors of 2-3,6-8, and 7-10 due to the presence of water for mono-, di- and tricarboxylic acids, respectively. Activity coefficients decreased by a factor of about 1.5 for ethanol and 1,2-propanediol as solutes. Water-enhanced solvation of phenols is small, when existent. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. NR 28 TC 3 Z9 3 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0888-5885 J9 IND ENG CHEM RES JI Ind. Eng. Chem. Res. PD MAY PY 1994 VL 33 IS 5 BP 1373 EP 1379 DI 10.1021/ie00029a037 PG 7 WC Engineering, Chemical SC Engineering GA NK617 UT WOS:A1994NK61700037 ER PT J AU ZHENG, ZB LITTLEJOHN, D CHANG, SG ZHUANG, YH AF ZHENG, ZB LITTLEJOHN, D CHANG, SG ZHUANG, YH TI HYDROLYSIS OF 2-AMINOETHANETHIOLSULFATE IONS SO INTERNATIONAL JOURNAL OF CHEMICAL KINETICS LA English DT Article ID FLUE-GAS AB The kinetics of the acid catalyzed hydrolysis of 2-aminoethanethiolsulfate (AETS) ions were investigated. The dependence of the hydrolysis rate constant on acidity and temperature was determined. The hydrolysis rate equation can be expressed as d[AETS]/dt = -kH(o)[AETS] where H(o) is the Hammett acidity function. The rate constant, k, can be expressed as (2) k = 9.0 x 10(12) L mol-1 s-1 exp(-115.9 kJ mol-1/RT). The pK(A)'s for the compound were measured and literature value of pK(a1) was found to be in error. The values determined in this study are pK(a1) < -0.5 and pK(a2) = 9.1 +/- 0.1. General acid catalysis of the hydrolysis reaction was found not to proceed to a significant degree. (C) 1994 John Wiley & Sons, Inc. C1 CHINESE ACAD SCI,ECOENVIRONM SCI RES CTR,BEIJING,PEOPLES R CHINA. RP ZHENG, ZB (reprint author), LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,BERKELEY,CA 94720, USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0538-8066 J9 INT J CHEM KINET JI Int. J. Chem. Kinet. PD MAY PY 1994 VL 26 IS 5 BP 545 EP 549 DI 10.1002/kin.550260507 PG 5 WC Chemistry, Physical SC Chemistry GA NG296 UT WOS:A1994NG29600006 ER PT J AU STACKHOUSE, MA BEDFORD, JS AF STACKHOUSE, MA BEDFORD, JS TI AN IONIZING RADIATION-SENSITIVE MUTANT OF CHO CELLS, IRS-20 .3. CHROMOSOME-ABERRATIONS, DNA BREAKS AND MITOTIC DELAY SO INTERNATIONAL JOURNAL OF RADIATION BIOLOGY LA English DT Article ID DOUBLE-STRAND BREAKS; CHINESE-HAMSTER CELLS; POTENTIALLY LETHAL DAMAGE; SISTER-CHROMATID EXCHANGE; ATAXIA-TELANGIECTASIA; MAMMALIAN-CELLS; SACCHAROMYCES-CEREVISIAE; GEL-ELECTROPHORESIS; HUMAN-FIBROBLASTS; OVARY CELLS AB The ionizing radiation-sensitive mutant of CHO cells, irs-20, showed a defect in the rate and extent of rejoining of gamma-ray-induced DNA double-strand breaks (dsbs) compared with the parental CHO cells as measured using pulsed-field gel electrophoresis. Virtually all rejoined in wild-type cells but some 20-30% failed to rejoin in the mutant cells during a 5-h period after irradiation. An increased level of chromosome-type aberrations per unit dose was seen in irs-20 cells compared with wild-type cells irradiated during the G(1) phase. For the irs-20 cells, about half the dose was required to produce the same chromosome-type aberration frequency. Chromatid-type aberrations were induced in G(1)-irradiated irs-20 cells at frequencies nearly the same as for chromosome types. For the parental wild-type CHO 10B2 cells, only chromosome types were seen. The distribution of aberrations among cells was not significantly different from Poisson for wild-type cells, but this was not the case for irs-20 cells where the overdispersion was highly significant. The mutant irs-20 cells displayed a much greater cell cycle delay per unit dose (about five-fold) in reaching mitosis after irradiation in G(1) than the more radioresistant wild-type parental cells. C1 COLORADO STATE UNIV,DEPT RADIOL HLTH SCI,FT COLLINS,CO 80523. LOS ALAMOS NATL LAB,CELL BIOL GRP,LOS ALAMOS,NM 87545. FU NCI NIH HHS [CA49501, CA18023] NR 72 TC 30 Z9 30 U1 0 U2 1 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNDPOWDER SQUARE, LONDON, ENGLAND EC4A 3DE SN 0955-3002 J9 INT J RADIAT BIOL JI Int. J. Radiat. Biol. PD MAY PY 1994 VL 65 IS 5 BP 571 EP 582 DI 10.1080/09553009414550661 PG 12 WC Biology; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Nuclear Science & Technology; Radiology, Nuclear Medicine & Medical Imaging GA NL831 UT WOS:A1994NL83100007 PM 7910196 ER PT J AU MAHAUT, S LEWIS, DK QUENTIN, G DEBILLY, M AF MAHAUT, S LEWIS, DK QUENTIN, G DEBILLY, M TI VISUALIZATION OF INTERNAL CAUSTICS IN CYLINDRICAL LIQUID CAVITIES WITH A PULSED SCHLIEREN SYSTEM SO JOURNAL DE PHYSIQUE IV LA English DT Article; Proceedings Paper CT 3rd French Conference on Acoustics CY MAY 02-06, 1994 CL UNIV TOULOUSE, TOULOUSE, FRANCE SP FRENCH ACOUST SOC, UNIV TOULOUSE LE MIRAIL HO UNIV TOULOUSE AB Visualizations of the acoustic field produced by reflection/refraction of bursts of plane longitudinal waves in the water-filled cylindrical cavity of a solid matrix have been made with a pulsed schlieren system. The positions of the cusp points of the caustics formed by successive internal reflections in the cavity have been compared with their theoretical geometrical values. The acoustic field produced by the reflection of a plane wave on a half-cylindrical mirror has also been studied and compared to the field in the vicinity of a caustic, according to the Pearcey approximation. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. CE SACLAY,CEA,SERV TECH AVANCEES,F-91191 GIF SUR YVETTE,FRANCE. RP MAHAUT, S (reprint author), UNIV PARIS 06,UNIV PARIS 07,GPS,TOUR 23,2 PL JUSSIEU,F-75251 PARIS 05,FRANCE. NR 4 TC 1 Z9 1 U1 0 U2 1 PU EDITIONS PHYSIQUE PI LES ULIS CEDEX PA Z I DE COURTABOEUF AVE 7 AV DU HOGGAR, BP 112, 91944 LES ULIS CEDEX, FRANCE SN 1155-4339 J9 J PHYS IV JI J. Phys. IV PD MAY PY 1994 VL 4 IS C5 BP 741 EP 744 DI 10.1051/jp4:19945160 PN 2 PG 4 WC Physics, Multidisciplinary SC Physics GA NT301 UT WOS:A1994NT30100017 ER PT J AU ARAUJO, AJ LABAVITCH, JM MORENO, AH AF ARAUJO, AJ LABAVITCH, JM MORENO, AH TI CHANGES IN THE CELL-WALL OF OLIVE FRUIT DURING PROCESSING SO JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY LA English DT Article ID PECTIC SUBSTANCES; CUCUMBER PICKLES; HEAT-TREATMENT; TOMATO FRUIT; POLYSACCHARIDES; FIRMNESS; CARROTS AB Olive fruits were sampled at various stages during their progress through the ''California Black Ripe'' process. Analysis of cell,walls prepared from these fruits indicated that processing was accompanied by general solubilization of polysaccharides and that pectins and a noncellulosic glucan component were most clearly affected. Soluble polysaccharides accumulated in processing liquids. Analysis of these and of polysaccharides extracted fr om cell walls suggests that the polymer most extensively solubilized and eluted during processing is a relatively unbranched pectin. C1 LAWRENCE LIVERMORE NATL LAB, DEPT POMOL, DAVIS, CA 95616 USA. NR 24 TC 11 Z9 11 U1 1 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0021-8561 EI 1520-5118 J9 J AGR FOOD CHEM JI J. Agric. Food Chem. PD MAY PY 1994 VL 42 IS 5 BP 1194 EP 1199 DI 10.1021/jf00041a027 PG 6 WC Agriculture, Multidisciplinary; Chemistry, Applied; Food Science & Technology SC Agriculture; Chemistry; Food Science & Technology GA NM298 UT WOS:A1994NM29800028 ER PT J AU STRICKLAND, JH AF STRICKLAND, JH TI PREDICTION METHOD FOR UNSTEADY AXISYMMETRICAL FLOW OVER PARACHUTES SO JOURNAL OF AIRCRAFT LA English DT Article AB A method which is capable of solving the axisymmetric flowfield over bluff bodies consisting of thin shells such as disks, partial spheres, rings, and other such shapes is presented in this article. The body may he made up of several shells whose edges are separated by gaps. The body may be moved axially according to arbitrary velocity time histories. In addition, the surfaces may posses axial and radial degrees of flexibility such that points on the surfaces may be allowed to move relative to each other according to some specified function of time. The surfaces may be either porous or impervious. The present solution technique is based on the axisymmetric vorticity transport equation. This technique requires relatively large numbers of ring vortices (1000 or more) to obtain good simulations. Since the direct calculation of perturbations from large numbers of ring vortices is computationally intensive, a fast multipole method was used to greatly reduce computer processing time. Several example calculations are presented for disks, disks with holes, hemispheres, and vented hemispheres. These results are compared with steady and unsteady experimental data. RP STRICKLAND, JH (reprint author), SANDIA NATL LABS,TECH STAFF,ALBUQUERQUE,NM 87185, USA. NR 0 TC 8 Z9 9 U1 0 U2 1 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0021-8669 J9 J AIRCRAFT JI J. Aircr. PD MAY-JUN PY 1994 VL 31 IS 3 BP 637 EP 643 DI 10.2514/3.46542 PG 7 WC Engineering, Aerospace SC Engineering GA NR637 UT WOS:A1994NR63700025 ER PT J AU WARNOW, TJ AF WARNOW, TJ TI TREE COMPATIBILITY AND INFERRING EVOLUTIONARY HISTORY SO JOURNAL OF ALGORITHMS LA English DT Article AB The tree compatibility problem is a problem concerned with evolutionary history construction. For a species set S, an S-labelled tree is a tree T along with a labelling L: S --> V(T). The tree compatibility problem asks whether a set T of S-labelled trees, each of which describes the evolution of S, is compatible in the sense that there is a single tree T* from which each tree T is-an-element-of T can be derived by a sequence of edge contractions. Polynomial time algorithms for the tree compatibility problem have been known to exist for a long time, with the best being the recent O(n2k) algorithm by Gusfield to determine compatibility of k trees on n species. Recently Gusfield found an O(nk) algorithm for a restricted case of the tree compatibility problem. In this paper, we will present an O(nk) algorithm for the tree compatibility problem, thus achieving linear time. The perfect phylogeny problem is another problem in evolutionary history construction, which has been recently shown to be in P for special cases but NP-complete for the general case. We will show that we can characterize each instance to the perfect phylogeny problem as an instance to the tree compatibility problem, and thus derive an algorithm for the perfect phylogeny problem. Our algorithm is superior to the other algorithms for perfect phylogeny problem for many realistic cases, such as when the species are defined by molecular data such as amino-acid sequences. (C) 1994 Academic Press, Inc. RP WARNOW, TJ (reprint author), SANDIA NATL LABS,DEPT ALGORITHMS & DISCRETE MATH,ALBUQUERQUE,NM 87185, USA. NR 22 TC 27 Z9 27 U1 0 U2 1 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0196-6774 J9 J ALGORITHM JI J. Algorithms PD MAY PY 1994 VL 16 IS 3 BP 388 EP 407 DI 10.1006/jagm.1994.1018 PG 20 WC Computer Science, Theory & Methods; Mathematics, Applied; Logic SC Computer Science; Mathematics; Science & Technology - Other Topics GA NE884 UT WOS:A1994NE88400003 ER PT J AU LEONESCAMILLA, EA CORBETT, JD AF LEONESCAMILLA, EA CORBETT, JD TI COMPOUNDS OF ALKALINE-EARTH AND DIVALENT RARE-EARTH-METALS STABILIZED BY HYDROGEN IMPURITIES - THE YB5SB3 AND MN5SI3 STRUCTURE TYPES FOR PNICTIDES SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Letter ID CHEMISTRY; ZR5SB3 AB All eight reported examples of the orthorhombic (beta-)Yb5Sb3-type structure are ternary hydrides, namely, A5(Sb,Bi)3H for A=Ca, Sr, Eu, Yb. One additional example is Sm5Bi3H. These may be obtained in quantitative yields through the inclusion of AH2 in the syntheses. On the contrary, heating these products or the elementary reactants at 900-1100-degrees-C in high vacuum while sealed in Ta regularly affords only hexagonal Mn5Si3-type products, i.e., A5Pn3 for A=Ca, Sr, Ba, Sm, Eu or Yb, Pn=As, Sb or Bi, except for As with Ba or Sm. The examples with Ca5Bi3, Eu5(Sb,Bi)3 and Yb5Bi3 are new. Several problems with supposedly dimorphic phases are thus clarified. The hydrogen content of the typical sublimed or distilled alkaline-earth metals is often particularly serious (approximately 6-20 at.% H). The A5Pn3 phases with either structure type take up variable amounts of hydrogen and thereby exhibit significant variations in their individual lattice constants. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT MED,AMES,IA 50011. NR 22 TC 46 Z9 46 U1 1 U2 9 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAY PY 1994 VL 206 IS 2 BP L15 EP L17 DI 10.1016/0925-8388(94)90025-6 PG 3 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA NK220 UT WOS:A1994NK22000003 ER PT J AU OTTINGER, PF ROSE, DV OLSON, CL AF OTTINGER, PF ROSE, DV OLSON, CL TI EFFECT OF TIME-OF-FLIGHT BUNCHING ON EFFICIENCY OF LIGHT-ION-BEAM INERTIAL-CONFINEMENT-FUSION TRANSPORT SCHEMES SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID CHANNELS; DESIGN; DIODE AB The Laboratory Microfusion Facility (LMF) has been proposed for the study of high-gain, high-yield inertial-confinement-fusion targets. The light-ion LMF approach uses a multimodular system with applied-B extraction diodes as ion sources. A number of ion-beam transport and focusing schemes are being considered to deliver the beams from the diodes to the target. These include ballistic transport with solenoidal lens focusing, z-discharge channel transport, and wire-guided transport. The energy transport efficiency eta(t) has been defined and calculated as a function of various system parameters so that point designs can be developed for each scheme. The analysis takes into account target requirements and realistic constraints on diode operation, beam transport, and packing. The effect on eta(t) of voltage ramping for time-of-flight beam bunching during transport is considered here. Although only 5 mrad microdivergence calculations are presented here, results for bunching factors of less-than-or-equal-to 3 show that transport efficiencies of >50% can be obtained for all three systems within a range of system parameters which seem achievable (i.e., for diode microdivergence within 5-10 mrad, for diode radius within 10-15 cm, and for diode-ion-current density within 2-10 kA/cm2). In particular, the point design for the baseline LMF system using ballistic transport with solenoidal lens focusing and a bunching factor of 2 was calculated to have eta(t) = 8 4 %. Other factors affecting the overall system efficiency, but not included in the analysis, are also identified and estimated. C1 JAYCOR INC,VIENNA,VA 22182. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP OTTINGER, PF (reprint author), USN,RES LAB,DIV PLASMA PHYS,WASHINGTON,DC 20375, USA. NR 29 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1994 VL 75 IS 9 BP 4402 EP 4414 DI 10.1063/1.355984 PG 13 WC Physics, Applied SC Physics GA NJ734 UT WOS:A1994NJ73400012 ER PT J AU MUCK, M HEIDEN, C CLARKE, J AF MUCK, M HEIDEN, C CLARKE, J TI INVESTIGATION AND REDUCTION OF EXCESS LOW-FREQUENCY NOISE IN RF SUPERCONDUCTING QUANTUM INTERFERENCE DEVICES SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID GRAIN-BOUNDARY JUNCTIONS; FLICKER 1/F NOISE; SQUID-MAGNETOMETER; TUNNEL-JUNCTIONS; DC SQUIDS; YBA2CU3O7-DELTA AB A detailed study has been made of the low-frequency excess noise of rf superconducting quantum interference devices (SQUIDs), fabricated from thin niobium films and operated at 4.2 K, with rf bias frequencies of 0.15, 1.7, and 3 GHz. When the SQUIDs were operated in an open-loop configuration in the absence of low-frequency flux modulation, the demodulated rf voltage exhibited a substantial level 1/f noise, which was essentially independent of the rf bias frequency. As the rf bias frequency was increased, the crossover frequency at which the 1/f noise power was equal to the white noise power moved to higher frequencies, because of the reduction in white noise. On the other hand, when the SQUID was flux modulated at 50 kHz and operated in a flux locked loop, no 1/f noise was observed at frequencies above 0.5 Hz. A detailed description of how the combination of rf bias and flux modulation removes 1/f noise due to critical current fluctuations is given. Thus, the results demonstrate that the 1/f noise observed in these SQUIDs is generated by critical current fluctuations, rather than by the hopping of flux vortices in the niobium films. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP MUCK, M (reprint author), FORSCHUNGSZENTRUM JULICH KFA,INST SCHICHT & IONENTECH,D-52425 JULICH,GERMANY. NR 23 TC 25 Z9 25 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1994 VL 75 IS 9 BP 4588 EP 4592 PG 5 WC Physics, Applied SC Physics GA NJ734 UT WOS:A1994NJ73400040 ER PT J AU LIN, XW WASHBURN, J LILIENTALWEBER, Z BERNAS, H AF LIN, XW WASHBURN, J LILIENTALWEBER, Z BERNAS, H TI COARSENING AND PHASE-TRANSITION OF FESI2 PRECIPITATES IN SI SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ION-BEAM SYNTHESIS; BURIED COSI2 LAYERS; SI/COSI2/SI STRUCTURES; IMPLANTATION; TEMPERATURE; SILICON; GROWTH AB FeSi2 precipitates were produced in Si(001) wafers by an ion-beam induced epitaxial crystallization process and subsequently annealed at temperatures in the range 650-900-degrees-C. The resulting precipitate coarsening and phase transition were studied by transmission electron microscopy. The coarsening process basically involves the evolution of plate-shaped precipitates. The lengthening rate of the precipitates is considerably greater than the thickening rate, because the two broad faces of a plate are coherent or semicoherent, while the plate edges are incoherent. The lengthening kinetics was shown to be volume-diffusion controlled and obey a cube power law. The corresponding activation energy was determined to be 3.55 eV, in excellent agreement with the value predicted by the classical Ostwald ripening model. In contrast, we demonstrated that the thickening process is interface controlled, which involves the migration of the interfaces via a ledge mechanism. Accordingly, an apparent activation energy of 2.18 eV was obtained. The precipitate coarsening is accompanied by phase transitions. Upon annealing at 650-degrees-C, it was observed that gamma-FeSi2 precipitates tend to transform from a fully aligned (A-type) to a twinned (B-type) orientation with respect to the Si matrix. For higher temperature anneals, nearly all the precipitates transform from the gamma phase into the beta phase, except those having a relatively small diameter (< almost-equal-to 5 nm) which remain as A-type gamma-FeSi2. These observations suggest that the phase transition of FeSi2 is size dependent. This can be understood, in terms of the interfacial energy versus the volume free energy of a precipitate as a function of precipitate size. C1 CTR SPECTROMETRIE NUCL & SPECTROMETRIE MASSE,F-91405 ORSAY,FRANCE. RP LIN, XW (reprint author), LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720, USA. RI Liliental-Weber, Zuzanna/H-8006-2012 NR 29 TC 18 Z9 18 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAY 1 PY 1994 VL 75 IS 9 BP 4686 EP 4694 DI 10.1063/1.355922 PG 9 WC Physics, Applied SC Physics GA NJ734 UT WOS:A1994NJ73400058 ER PT J AU BANTLE, JA BURTON, DT DAWSON, DA DUMONT, JN FINCH, RA FORT, DJ LINDER, G RAYBURN, JR BUCHWALTER, D MAURICE, MA TURLEY, SD AF BANTLE, JA BURTON, DT DAWSON, DA DUMONT, JN FINCH, RA FORT, DJ LINDER, G RAYBURN, JR BUCHWALTER, D MAURICE, MA TURLEY, SD TI INITIAL INTERLABORATORY VALIDATION-STUDY OF FETAX - PHASE-I TESTING SO JOURNAL OF APPLIED TOXICOLOGY LA English DT Article DE FETAX; XENOPUS; TERATOGEN; HYDROXYUREA; ISONIAZID; 6-AMINONICOTINAMIDE; INTERLABORATORY VALIDATION ID EMBRYO TERATOGENESIS ASSAY; METABOLIC-ACTIVATION SYSTEM; DECLINING AMPHIBIAN POPULATIONS; INDUCED DEVELOPMENTAL TOXICITY; XENOPUS FETAX; IDENTIFICATION; EFFICACY AB An interlaboratory validation study was undertaken to evaluate the repeatability and reliability of the Frog Embryo Teratogenesis Assay-Xenopus (FETAX), which is a whole embryo developmental toxicity screening assay. A three-phase experimental program with seven participants was carried out. Phase I was a training and protocol evaluation phase where the identity of the three test materials was known. Hydroxyurea, isoniazid and 6-aminonicotinamide were tested in Phase I. Because the chemicals has been tested previously in FETAX, the same concentrations needed to establish the 96-h median lethal concentration (LC(50)) and the concentration inducing malformations in 50% of the surviving embryos (EC(50)) were used by all laboratories. The results of Phase I are presented in this report, and FETAX has proved to be as repeatable and reliable as many other bioassays. Some excess variation was observed in individual laboratories. Some of this variation may have been due to training difficulties. One change in protocol design necessitated by this study was the use of 6-aminonicotinamide as a reference toxicant. While 6-aminonicotinamide provided excellent concentration-response data in most laboratories, the protocol was written too strictly based on historical FETAX data. Phases II and m are currently in progress. C1 UNIV MARYLAND,WYE RES & EDUC CTR,QUEENSTOWN,MD 21658. UNIV TENNESSEE,COLL VET MED,KNOXVILLE,TN 37901. OAK RIDGE NATL LAB,DEPT QUAL,OAK RIDGE,TN 37830. USA,BIOMED RES & DEV LAB,FREDERICK,MD 21702. STOVER BIOMETR LABS INC,STILLWATER,OK 74076. MANTECH ENVIRONM TECHNOL INC,ENVIRONM RES LAB,CORVALLIS,OR 97333. RP BANTLE, JA (reprint author), OKLAHOMA STATE UNIV,DEPT ZOOL,STILLWATER,OK 74078, USA. NR 39 TC 25 Z9 28 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0260-437X J9 J APPL TOXICOL JI J. Appl. Toxicol. PD MAY-JUN PY 1994 VL 14 IS 3 BP 213 EP 223 DI 10.1002/jat.2550140312 PG 11 WC Toxicology SC Toxicology GA NQ006 UT WOS:A1994NQ00600012 PM 8083483 ER PT J AU BUTLER, VL CHATTERS, JC AF BUTLER, VL CHATTERS, JC TI THE ROLE OF BONE-DENSITY IN STRUCTURING PREHISTORIC SALMON BONE ASSEMBLAGES SO JOURNAL OF ARCHAEOLOGICAL SCIENCE LA English DT Article DE SALMON BONE DENSITY; X-RAY ABSORPTIOMETRY; BONE VOLUME; SALMON TAPHONOMY; SALMON STORAGE; PREHISTORIC SALMON; FISH BUTCHERING; NORTH-WESTERN NORTH-AMERICA C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. N AMER PALEOSCI, RICHLAND, WA 99352 USA. NR 47 TC 78 Z9 82 U1 0 U2 1 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0305-4403 J9 J ARCHAEOL SCI JI J. Archaeol. Sci. PD MAY PY 1994 VL 21 IS 3 BP 413 EP 424 DI 10.1006/jasc.1994.1039 PG 12 WC Anthropology; Archaeology; Geosciences, Multidisciplinary SC Anthropology; Archaeology; Geology GA NT799 UT WOS:A1994NT79900011 ER PT J AU DUNN, JJ BUCHSTEIN, SR BUTLER, LL FISENNE, S POLIN, DS LADE, BN LUFT, BJ AF DUNN, JJ BUCHSTEIN, SR BUTLER, LL FISENNE, S POLIN, DS LADE, BN LUFT, BJ TI COMPLETE NUCLEOTIDE-SEQUENCE OF A CIRCULAR PLASMID FROM THE LYME-DISEASE SPIROCHETE, BORRELIA-BURGDORFERI SO JOURNAL OF BACTERIOLOGY LA English DT Article ID MOLECULAR ANALYSIS; ESCHERICHIA-COLI; LINEAR-PLASMID; STRANDED-DNA; AGENT; RECOMBINATION; CULTIVATION; CHROMOSOME; PROTEINS; ELEMENTS AB We have determined the complete nucleotide sequence of a small circular plasmid from the spirochete Borrelia burgdorferi Ip21, the agent of Lyme disease. The plasmid (cp8.3/Ip21) is 8,303 bp long, has a 76.6% A+T content, and is unstable upon passage of cells in vitro. An analysis of the sequence revealed the presence of two nearly perfect copies of a 184-bp inverted repeat sequence separated by 2,675 bp containing three closely spaced, but nonoverlapping, open reading frames (ORFs). Each inverted repeat ends in sequences that may function as signals for the initiation of transcription and translation of flanking plasmid sequences. A unique oligonucleotide probe based on the repeated sequence shelved that the DNA between the repeats is present predominantly in a single orientation. Additional copies of the repeat were not detected elsewhere in the Ip21 genome. An analysis for potential ORFs indicates that the plasmid has nine highly probable protein-coding ORFs and one that is less probable; together, they occupy almost 71% of the nucleotide sequence. Analysis of the deduced amino acid sequences of the ORFs revealed one (ORF-9) with features in common with Borrelia lipoproteins and another (ORF-2) having limited homology with a replication protein, RepC, from a gram-positive plasmid that replicates by a rolling circle (RC) mechanism. Known collectively as RC plasmids, such plasmids require a double-stranded origin at which the Rep protein nicks the DNA to generate a single-stranded replication intermediate. cp8.3/Ip21 has three copies of the heptameric motif characteristically found at a nick site of most RC plasmids. These observations suggest that cp8.3/Ip21 may replicate by an RC mechanism. C1 SUNY HLTH SCI CTR STONY BROOK,DEPT MED,STONY BROOK,NY 11933. RP DUNN, JJ (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. OI Luft, Benjamin/0000-0001-9008-7004 FU NIAID NIH HHS [R01AI32454] NR 56 TC 51 Z9 51 U1 0 U2 0 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 SN 0021-9193 J9 J BACTERIOL JI J. Bacteriol. PD MAY PY 1994 VL 176 IS 9 BP 2706 EP 2717 PG 12 WC Microbiology SC Microbiology GA NJ081 UT WOS:A1994NJ08100031 PM 8169221 ER PT J AU SCHREUDERS, PD DILLER, KR BEAMAN, JJ PAYNTER, HM AF SCHREUDERS, PD DILLER, KR BEAMAN, JJ PAYNTER, HM TI AN ANALYSIS OF COUPLED MULTICOMPONENT DIFFUSION IN INTERSTITIAL-TISSUE SO JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB A one-dimensional multicomponent kinetic model was developed to simulate the interstitial diffusion of macromolecules in a three component system, consisting of water, the macromolecule and the interstitial matrix. Movement of the individual components was modeled as occurring in finite jumps between discrete low energy wells along paths defined in terms of species occupation. The flow rate was expressed as a function of the local species concentration, the jump distance, and a kinetic frequency parameter. The model, implemented in pseudo-bond graph form, was examined by fitting it to data obtained for the transport of fluorescein tagged dextran to determine the kinetic constants for that specific system. C1 OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. UNIV TEXAS,DEPT MECH ENGN,BIOMED ENGN PROGRAM,AUSTIN,TX 78712. RP SCHREUDERS, PD (reprint author), UNIV TENNESSEE,GRAD SCH BIOMED SCI,KNOXVILLE,TN 37996, USA. FU NIGMS NIH HHS [GM 23-21681] NR 25 TC 12 Z9 12 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0148-0731 J9 J BIOMECH ENG-T ASME JI J. Biomech. Eng.-Trans. ASME PD MAY PY 1994 VL 116 IS 2 BP 164 EP 171 DI 10.1115/1.2895715 PG 8 WC Biophysics; Engineering, Biomedical SC Biophysics; Engineering GA NP759 UT WOS:A1994NP75900005 PM 7521448 ER PT J AU SYMPSON, CJ TALHOUK, RS ALEXANDER, CM CHIN, JR CLIFT, SM BISSELL, MJ WERB, Z AF SYMPSON, CJ TALHOUK, RS ALEXANDER, CM CHIN, JR CLIFT, SM BISSELL, MJ WERB, Z TI TARGETED EXPRESSION OF STROMELYSIN-1 IN MAMMARY-GLAND PROVIDES EVIDENCE FOR A ROLE OF PROTEINASES IN BRANCHING MORPHOGENESIS AND THE REQUIREMENT FOR AN INTACT BASEMENT-MEMBRANE FOR TISSUE-SPECIFIC GENE-EXPRESSION SO JOURNAL OF CELL BIOLOGY LA English DT Article ID EXTRACELLULAR-MATRIX; TRANSGENIC MICE; EPITHELIAL-CELLS; BREAST-CANCER; MOUSE; RAT; GROWTH; COLLAGENASE; INVOLUTION; PROMOTER AB The extracellular matrix (ECM) is an important regulator of the differentiated phenotype of mammary epithelial cells in culture. Despite the fact that ECM-degrading enzymes have been implicated in morphogenesis and tissue remodeling, there is little evidence for a direct role for such regulation in vivo. We generated transgenic mice that express autoactivated isoforms of the matrix metalloproteinase stromelysin-1, under the control of the whey acidic protein gene promoter, to examine the effect of inappropriate expression of this enzyme. Stromelysin-1 is implicated as the primary player in the loss of basement membrane and loss of function in the mammary gland during involution. The transgene was expressed at low levels in mammary glands of virgin female mice, leading to an unexpected phenotype: The primary ducts had supernumerary branches and showed precocious development of alveoli that expressed beta-casein at levels similar to that of an early- to mid-pregnant gland. Lactating glands showed high levels of transgene expression, with accumulation at the basement membrane, and a decrease in laminin and collagen IV, resulting in a loss of basement membrane integrity; this was accompanied by a dramatic alteration of alveolar morphology, with decreased size and shrunken lumina containing little beta-casein. During pregnancy, expression of endogenous whey acidic protein and beta-casein was reduced in transgenic glands, confirming the observed dependence of milk protein transcription on ECM in mammary epithelial cells in culture. These data provide direct evidence that stromelysin-1 activity can be morphogenic for mammary epithelial cells, inducing hyperproliferation and differentiation in virgin animals, and that its lytic activity can, indeed, disrupt membrane integrity and reduce mammary-specific function. We conclude that the balance of ECM-degrading enzymes with their inhibitors, and the associated regulation of ECM structure, is crucial for tissue-specific gene expression and morphogenesis in vivo. C1 UNIV CALIF SAN FRANCISCO,RADIOBIOL & ENVIRONM HLTH LAB,SAN FRANCISCO,CA 94143. UNIV CALIF SAN FRANCISCO,DEPT ANAT,SAN FRANCISCO,CA 94143. RP SYMPSON, CJ (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV LIFE SCI,1 CYCLOTRON RD,BLDG 83,BERKELEY,CA 94720, USA. FU NCI NIH HHS [CA 57621]; NICHD NIH HHS [HD 23539]; NIEHS NIH HHS [ES07106] NR 59 TC 354 Z9 355 U1 0 U2 9 PU ROCKEFELLER UNIV PRESS PI NEW YORK PA 1114 FIRST AVE, 4TH FL, NEW YORK, NY 10021 SN 0021-9525 J9 J CELL BIOL JI J. Cell Biol. PD MAY PY 1994 VL 125 IS 3 BP 681 EP 693 DI 10.1083/jcb.125.3.681 PG 13 WC Cell Biology SC Cell Biology GA NJ950 UT WOS:A1994NJ95000016 PM 8175886 ER PT J AU SPINING, MT DARSEY, JA SUMPTER, BG NOID, DW AF SPINING, MT DARSEY, JA SUMPTER, BG NOID, DW TI OPENING UP THE BLACK-BOX OF ARTIFICIAL NEURAL NETWORKS SO JOURNAL OF CHEMICAL EDUCATION LA English DT Article ID HEAT-CAPACITIES; MACROMOLECULES; POLYMERS C1 UNIV ARKANSAS MED SCI HOSP,LITTLE ROCK,AR 72205. OAK RIDGE NATL LAB,DIV CHEM,OAK RIDGE,TN 37831. RP SPINING, MT (reprint author), UNIV TENNESSEE,KNOXVILLE,TN 37996, USA. RI Sumpter, Bobby/C-9459-2013 OI Sumpter, Bobby/0000-0001-6341-0355 NR 19 TC 20 Z9 20 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0021-9584 J9 J CHEM EDUC JI J. Chem. Educ. PD MAY PY 1994 VL 71 IS 5 BP 406 EP 411 PG 6 WC Chemistry, Multidisciplinary; Education, Scientific Disciplines SC Chemistry; Education & Educational Research GA NN507 UT WOS:A1994NN50700013 ER PT J AU SIGMAN, ME RIVES, SS AF SIGMAN, ME RIVES, SS TI PREDICTION OF ATOMIC IONIZATION-POTENTIALS I-III USING AN ARTIFICIAL NEURAL-NETWORK SO JOURNAL OF CHEMICAL INFORMATION AND COMPUTER SCIENCES LA English DT Article ID DIRAC-FOCK CALCULATIONS; INFRARED-SPECTRA; FLUORESCENCE-SPECTRA; RECOGNITION; IDENTIFICATION; MACROMOLECULES; PROPAGATION; SHIFTS; RADII; IONS AB A simple three-layer back-propagation neural network is shown to learn the complex relationship between the electronic structure and the first three ionization potentials (log{IP(eV)}) of 222 atoms and ions for which spectroscopic data have been determined. The neural network was trained to a root mean square error of 0.043 log units and was subsequently used to predict ionization potentials which were not included in the training set and values which have not been experimentally determined. The neural network predictions are in very good agreement with experimental values not included in the training data set. In addition, the neural network predicts IP for elements 73, 104, and 105 which are also in good agreement with those values predicted by highly sophisticated multiconfiguration Dirac-Fock (MCDF) calculations. RP SIGMAN, ME (reprint author), OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,POB 2008,MS 6100,OAK RIDGE,TN 37831, USA. NR 34 TC 13 Z9 14 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0095-2338 J9 J CHEM INF COMP SCI JI J. Chem. Inf. Comput. Sci. PD MAY-JUN PY 1994 VL 34 IS 3 BP 617 EP 620 DI 10.1021/ci00019a021 PG 4 WC Chemistry, Multidisciplinary; Computer Science, Information Systems; Computer Science, Interdisciplinary Applications SC Chemistry; Computer Science GA NN745 UT WOS:A1994NN74500021 ER PT J AU DESHMUKH, S HESS, WP AF DESHMUKH, S HESS, WP TI PHOTODISSOCIATION OF ACETYL-CHLORIDE - CL AND CH, QUANTUM YIELDS AND ENERGY-DISTRIBUTIONS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ENHANCED MULTIPHOTON IONIZATION; DOPPLER SPECTROSCOPY; ALPHA-BOND; 193 NM; DYNAMICS; ACETONE; EXCITATION; HALIDES; LASER AB Jet cooled acetyl chloride is dissociated at 236 nm via excitation of the (1)[n, pi* (C=O)] transition. Chlorine atom photofragments Cl(P-2(3/2)) and Cl*(P-2(1/2)) are detected using (2+1) multiphoton ionization. The relative Cl* yield phi*=[Cl*]/([Cl]+[Cl*]) is measured to be 0.4+/-0.02, and the mean translational energy of the Cl atoms is 0.28+/-0.02 eV. Methyl fragments are also detected following primary dissociation and the internal state distributions are probed using (2+1) multiphoton ionization through the 4p(z) Rydberg state at 286 nm and the 3p(z) Rydberg state at 334 nm. The quantum yield for CH3 formation is estimated to be 28%, relative to the CH3 yield from methyl iodide photolysis. A small fraction of the available energy is channeled into methyl fragment angular momentum as the rotational state distribution extends only to N''=5. Our results indicate that CH3CO, generated as a primary photoproduct in the dissociation of acetyl chloride, subsequently decomposes to produce CH3 and CO, Energetic constraints in the mechanism of acetyl chloride dissociation are discussed. RP DESHMUKH, S (reprint author), PACIFIC NW LAB, POB 999, RICHLAND, WA 99352 USA. NR 29 TC 41 Z9 41 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1994 VL 100 IS 9 BP 6429 EP 6433 DI 10.1063/1.467052 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NH846 UT WOS:A1994NH84600033 ER PT J AU YANG, S HILL, WT DIXIT, SN AF YANG, S HILL, WT DIXIT, SN TI MULTIPHOTON DISSOCIATIVE IONIZATION OF O-2 - COMPETITION BETWEEN DISSOCIATION AND IONIZATION IN EXCITED-STATES SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SCHUMANN-RUNGE BANDS; HIGH-RESOLUTION; PHOTOIONIZATION; PREDISSOCIATION; CHANNELS; H-2; CO; O2 AB A mass and energy resolved photoion spectrum of O-2 induced by 12 ns 193 nm radiation with an intensity of 10(10)-10(11) W/cm(2) is presented. The analysis of the spectrum gives (1) the two-photon ionization cross section (approximate to 1.1X10(-54) cm(4) s) of the X (3) Sigma(g)(-) of O-2 and (2) the intensity dependent branching ratios between photoionization and predissociation of the B (3) Sigma(u)(-) state of O-2 The two-photon ionization cross section of O-2 is linked to our ab initio calculation of the three-photon ionization cross section (approximate to 7.5X.10(-84) cm(6) s(2)) of atomic oxygen. C1 LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. RP YANG, S (reprint author), UNIV MARYLAND, INST PHYS SCI & TECHNOL, COLL PK, MD 20742 USA. NR 34 TC 7 Z9 8 U1 0 U2 6 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1994 VL 100 IS 9 BP 6434 EP 6444 DI 10.1063/1.467053 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NH846 UT WOS:A1994NH84600034 ER PT J AU YEAGER, DL NICHOLS, JA GOLAB, JT AF YEAGER, DL NICHOLS, JA GOLAB, JT TI THE POTENTIAL-ENERGY CURVES OF THE X(2)PI(G), A(4)PI(U), A(2)PI(U), B(4)SIGMA(-)(G), B(2)SIGMA(-)(G), (2)PI(U), AND C(4)SIGMA(-)(U) STATES OF O-2(+) OBTAINED USING THE MULTICONFIGURATIONAL SPIN TENSOR ELECTRON PROPAGATOR METHOD SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID PHOTOIONIZATION CROSS-SECTIONS; BODY PERTURBATION-THEORY; MOLECULAR CALCULATIONS; IONIZATION-POTENTIALS; OPEN-SHELL; BASIS-SETS; CN; AFFINITIES; O2; OH AB With electron propagator methods, electronic ionization and attachment energies are obtained directly. The multiconfigurational spin tensor electron propagator method (MCSTEP) is explicitly designed for systems with open shell and/or nondynamical correlation in the initial state. We apply MCSTEP to O-2 at several internuclear separations and obtain and report the MCSTEP potential energy curves and the spectroscopic constants for the X(2)II(g),a(4)II(u),A(2)II(u),b(4) Sigma(g)(-),B-2 Sigma(g)(-),(IIu)-I-2, and c(4) Sigma(u)(-) states of O-2(+). C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. AMOCO CHEM CO, NAPERVILLE, IL 60566 USA. RP YEAGER, DL (reprint author), TEXAS A&M UNIV, DEPT CHEM, COLLEGE STN, TX 77843 USA. RI Yeager, Danny/D-3679-2015 OI Yeager, Danny/0000-0001-9832-0034 NR 47 TC 19 Z9 19 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1994 VL 100 IS 9 BP 6514 EP 6519 DI 10.1063/1.467060 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NH846 UT WOS:A1994NH84600043 ER PT J AU MESSINA, M GARRETT, BC SCHENTER, GK AF MESSINA, M GARRETT, BC SCHENTER, GK TI VARIATIONAL SOLUTIONS FOR THE THERMAL AND REAL-TIME PROPAGATOR USING THE MCLACHLAN VARIATIONAL PRINCIPLE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MONTE-CARLO METHODS; PATH-INTEGRALS; EVOLUTION; DYNAMICS AB A new approximation to the propagator is presented. The approximation as applied to the thermal propagator (coordinate space density matrix) is obtained by using an analog of the McLachlan variational principle for the solution of the Bloch equation. The approximation as applied to the real time propagator is obtained by using the McLachlan variational principle for the solution of the time-dependent Schrodinger equation. The-approximate coordinate space density matrix has the same functional form of the high temperature limit of the density matrix, while the approximate real time propagator has-the same functional form-as the short time propagator. We present numerical results for the thermal propagator for several test systems and compare these results to previous work of Zhang, Levy; and Freisner [Chem. Phys, Lett. 144, 238 (1988)], Mak and Andersen [J. Chem. Phys. 92, 2953 (1990)], and Cao and Berne [J. Chem. Phys. 92, 7531 (1990)]. We also present numerical results for: the approximate real time propagator for several test systems and compare to the exact results and results obtained by Gaussian wave packet propagation. RP MESSINA, M (reprint author), PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. RI Garrett, Bruce/F-8516-2011; Schenter, Gregory/I-7655-2014 OI Schenter, Gregory/0000-0001-5444-5484 NR 24 TC 12 Z9 12 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1994 VL 100 IS 9 BP 6570 EP 6577 DI 10.1063/1.467066 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NH846 UT WOS:A1994NH84600049 ER PT J AU BIRKENHEUER, U BOETTGER, JC ROSCH, N AF BIRKENHEUER, U BOETTGER, JC ROSCH, N TI CHARGE SEPARATION AND COVALENT BONDING IN METAL-OXIDE SURFACES - A LOCAL-DENSITY FUNCTIONAL-STUDY ON THE MGO(001) SURFACE SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID MAGNESIUM-OXIDE; CO ADSORPTION; HARTREE-FOCK; ELECTRONIC-STRUCTURE; MGO SURFACES; X-RAY; MODEL; ABINITIO; CHEMISORPTION; MOLECULES AB A first principles local density functional investigation on extended, two-dimensional periodic slab models of the MgO(001) surface is performed, using the linear combination of Gaussian-type orbitals (LCGTO) technique as implemented in the FILMS program package. Stimulated by recent theoretical evidence for a reduced charge separation in MgO(001), a detailed analysis of the charge distribution and its influence on the electrical field above the surface is carried out. Two different methods to quantify the charge separation in the ionic substrate are employed, a local one based on the topological atom approach and a global one derived from the Madelung field of the surface near potential adsorbates. Both procedures lead to a charge separation significantly (10%-20%) below the nominal ionic value of +/-2 a.u. A variational atomic orbital analysis is utilized to discuss the origin of the Mg 3s and 3p structures discernible in the crystal orbitals of the MgO slab systems. They are identified as covalent magnesium valence orbital admixtures to the oxygen dominated valence bands in consistence with the reduced charge separation. Their influence on the cohesive energy of crystalline MgO,however, is found to be only 5% (similar to 0.5 eV). C1 TECH UNIV MUNICH,LEHRSTUHL THEORET CHEM,D-85747 GARCHING,GERMANY. LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RI Roesch, Notker/C-1182-2010 NR 54 TC 73 Z9 73 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1994 VL 100 IS 9 BP 6826 EP 6836 DI 10.1063/1.467042 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NH846 UT WOS:A1994NH84600079 ER PT J AU CHRISTOPHOROU, LG DATSKOS, PG CARTER, JG AF CHRISTOPHOROU, LG DATSKOS, PG CARTER, JG TI TEMPERATURE-ENHANCED ELECTRON DETACHMENT FROM C6F6- NEGATIVE-IONS - REPLY SO JOURNAL OF CHEMICAL PHYSICS LA English DT Letter ID PERFLUOROBENZENE RP CHRISTOPHOROU, LG (reprint author), OAK RIDGE NATL LAB,DIV HLTH SCI RES,ATOM MOLEC & HITH VOLTAGE PHYS GRP,OAK RIDGE,TN 37831, USA. NR 4 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAY 1 PY 1994 VL 100 IS 9 BP 6983 EP 6983 DI 10.1063/1.467018 PG 1 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NH846 UT WOS:A1994NH84600098 ER PT J AU PETTIT, DR PETERSON, DE KUBATMARTIN, KA PETROVIC, JJ SHEINBERG, H COULTER, Y DAY, DE AF PETTIT, DR PETERSON, DE KUBATMARTIN, KA PETROVIC, JJ SHEINBERG, H COULTER, Y DAY, DE TI PROCESSING YTTRIUM BARIUM COPPER-OXIDE SUPERCONDUCTOR IN NEAR-ZERO GRAVITY SO JOURNAL OF CRYSTAL GROWTH LA English DT Article ID MELT AB The effects of processing YBa2Cu3Ox (Y123) superconductor in the near-zero gravity (0 g) environment provided by the NASA KC-135 airplane flying on parabolic trajectories were studied. A new sheet float zone furnace, designed for this study, enabled fast temperature ramps. Up to an 18 g sample was processed with each parabola. Samples of Y123 were processed as bulk sheets and composites containing Ag and Pd. The 0 g processed samples were multi-phase yet retained a localized Y123 stoichiometry where a single ground-based (1 g) oxygen anneal at temperatures of 800-degrees-C recovered nearly 100 vol% superconducting Y123. The 1 g processed control samples remained multi-phase after the same ground-based anneal with less than 45 vol% as superconducting Y123. The superconducting transition temperature was 91 K for both 0 g and 1 g processed samples. Melt texturing of bulk Y123 in 0 g produced aligned grains about a factor of three larger than in analogous 1 g samples. Transport-critical current densities were at or below 18 A/CM2, due to the formation of cracks caused by the rapid heating rates required by the short time at 0 g. C1 UNIV MISSOURI,ROLLA,MO 65401. RP PETTIT, DR (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544, USA. NR 16 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-0248 J9 J CRYST GROWTH JI J. Cryst. Growth PD MAY PY 1994 VL 139 IS 3-4 BP 302 EP 308 DI 10.1016/0022-0248(94)90179-1 PG 7 WC Crystallography; Materials Science, Multidisciplinary; Physics, Applied SC Crystallography; Materials Science; Physics GA NJ954 UT WOS:A1994NJ95400013 ER PT J AU KURTZ, SR OLSON, JM FRIEDMAN, DJ KIBBLER, AE ASHER, S AF KURTZ, SR OLSON, JM FRIEDMAN, DJ KIBBLER, AE ASHER, S TI ORDERING AND DISORDERING OF DOPED GA0.5IN0.5P SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE BAND GAP; GAINP; ORDER-DISORDER ID VAPOR-PHASE EPITAXY; BAND-GAP ENERGY; ALLOY SEMICONDUCTORS; GROWTH-RATE; GAINP; GAAS; GA0.51IN0.49P; DIFFUSION; ALGAINP AB The band gap of Ga0.5In0.5P is reported as a function of doping level and growth rate. The lowest band gaps are obtained for hole concentrations of about 2 x 10(17) cm-3. For samples doped p-type above 1 x 10(18) cm-3, the band gap increases dramatically, regardless of growth rate. This effect is shown to be the result of disordering during growth rather than a change in the equilibrium surface structure with doping. The doping level dependence of the band gap of Ga0.5In0.5P samples grown at higher and lower growth rates differs for selenium and zinc doping even though the effects of high doping are the same for both dopants. RP KURTZ, SR (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 22 TC 24 Z9 24 U1 0 U2 6 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAY PY 1994 VL 23 IS 5 BP 431 EP 435 DI 10.1007/BF02671225 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA NJ539 UT WOS:A1994NJ53900001 ER PT J AU GOLDSTEIN, JLF MORRIS, JW AF GOLDSTEIN, JLF MORRIS, JW TI MICROSTRUCTURAL DEVELOPMENT OF EUTECTIC BI-SN AND EUTECTIC IN-SN DURING HIGH-TEMPERATURE DEFORMATION SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article DE BI-SN; CREEP; IN-SN; MICROSTRUCTURE ID DYNAMIC RECRYSTALLIZATION; SOLDER JOINTS; INDIUM; TIN AB Eutectic Bi-Sn and In-Sn solder joints were subjected to high temperature deformation in shear in order to determine whether microstructural instabilities are generated during testing. Dynamic recrystallization had previously been observed in Sn-Pb solder joints during creep and fatigue in shear. The current study shows that Bi-Sn can recrystallize during deformation in creep or at constant strain rate, whereas no microstructural changes are observed in In-Sn. Recrystallization of Bi-Sn is concentrated in a narrow band along the length of the sample, parallel to the direction of shear strain, similar to behavior in Sn-Pb. The recrystallization appears to proceed by migration of interphase boundaries rather than by a nucleation and growth mechanism. A minimum total strain is required to induce obvious recrystallization in Bi-Sn, independent of applied stress or strain rate. This value of strain is much higher than the strain at initiation of tertiary creep or at the maximum shear stress. Onset of tertiary creep and strain softening occur as a result of nonuniform deformation in the samples that is independent of the microstructural instabilities. The creep behavior of In-Sn is relatively straightforward, with a single creep mechanism operating at all temperatures tested. The creep behavior of Bi-Sn is temperature-dependent. Two mechanisms operate at lower temperatures, but there is still some question as to whether one or both of these, or a third mechanism, operates at higher temperatures. C1 UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720. RP GOLDSTEIN, JLF (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720, USA. NR 37 TC 32 Z9 32 U1 2 U2 5 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD MAY PY 1994 VL 23 IS 5 BP 477 EP 486 DI 10.1007/BF02671233 PG 10 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA NJ539 UT WOS:A1994NJ53900009 ER PT J AU MCCALLEN, DB ROMSTAD, KM AF MCCALLEN, DB ROMSTAD, KM TI NONLINEAR MODEL FOR BUILDING-SOIL SYSTEMS SO JOURNAL OF ENGINEERING MECHANICS-ASCE LA English DT Article ID UPLIFT AB A finite-clement based, numerical analysis methodology has been developed for the nonlinear analysis of building-soil systems. The methodology utilizes a reduced-order, nonlinear continuum model to represent the building, and the soil is represented with a simple nonlinear two-dimensional plane strain finite element. The foundation of the building is idealized as a rigid block and the interface between the soil and the foundation is modeled with an interface contact element. The objectives of the current paper are to provide the theoretical development of the system model, with particular emphasis on the modeling of the foundation-soil contact, and to demonstrate the special-purpose finite-element program that has been developed for nonlinear analysis of the building-soil system. Examples are included that compare the results obtained with the special-purpose program with the results of a general-purpose nonlinear finite-clement program. C1 UNIV CALIF DAVIS,DEPT CIVIL ENGN,DAVIS,CA 95616. RP MCCALLEN, DB (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 19 TC 11 Z9 11 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9399 J9 J ENG MECH-ASCE JI J. Eng. Mech.-ASCE PD MAY PY 1994 VL 120 IS 5 BP 1129 EP 1152 DI 10.1061/(ASCE)0733-9399(1994)120:5(1129) PG 24 WC Engineering, Mechanical SC Engineering GA NG743 UT WOS:A1994NG74300012 ER PT J AU LABIENIEC, PA DZOMBAK, DA SIEGRIST, RL AF LABIENIEC, PA DZOMBAK, DA SIEGRIST, RL TI RISK VARIABILITY FROM UNIFORM SOIL REMEDIATION GOALS FOR PCBS SO JOURNAL OF ENVIRONMENTAL ENGINEERING-ASCE LA English DT Article ID VAPOR AB A methodology for evaluating the variability of risk resulting from the use of uniform, concentration-based soil-quality criteria is developed and applied to polychlorinated-biphenyl (PCB-) contaminated soil as an example. A modified version of a soil risk model developed by the U.S. Environmental Protection Agency is used to assess risk variability for different levels of PCBs in soil. representing different cleanup goals. Continuous distributions representing the variability in site conditions across the United States are assigned to parameters in the fate and transport model to examine the effect that such variability has on individual risk when uniform cleanup levels for PCBs in soil are used. It is found that for a fixed cleanup goal applied uniformly to all sites, the risk varies little for the case where the hypothetical exposure occurs on-site, but by as much as two orders of magnitude for the case where the hypothetical maximally exposed individual resides off-site. Depending on the risk goal of the remediation program, some risk variability may be acceptable and a uniform cleanup goal may be warranted to expedite the remediation process. C1 CARNEGIE MELLON UNIV,DEPT CIVIL ENGN,PITTSBURGH,PA 15213. OAK RIDGE NATL LAB,DIV HLTH & SAFETY RES,DEPT CIVIL ENGN,OAK RIDGE,TN 37830. RP LABIENIEC, PA (reprint author), CARNEGIE MELLON UNIV,DEPT ENGN & PUBL POLICY,PITTSBURGH,PA 15213, USA. NR 20 TC 5 Z9 5 U1 0 U2 0 PU ASCE-AMER SOC CIVIL ENGINEERS PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017-2398 SN 0733-9372 J9 J ENVIRON ENG-ASCE JI J. Environ. Eng.-ASCE PD MAY-JUN PY 1994 VL 120 IS 3 BP 495 EP 512 DI 10.1061/(ASCE)0733-9372(1994)120:3(495) PG 18 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA NM610 UT WOS:A1994NM61000010 ER PT J AU WALTHOUR, DW SONNERUP, BUO ELPHIC, RC RUSSELL, CT AF WALTHOUR, DW SONNERUP, BUO ELPHIC, RC RUSSELL, CT TI DOUBLE VISION - REMOTE-SENSING OF A FLUX-TRANSFER EVENT WITH ISEE-1 AND ISEE-2 SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID MAGNETOPAUSE; RECONNECTION; FIELDS AB A flux transfer event recorded by the ISEE 1 and 2 spacecraft in the northern hemisphere near local noon is examined using analysis techniques developed recently for determination from single satellite magnetometer data of the orientation and cross-sectional shape of a two-dimensional disturbance moving along the magnetopause. The analysis is performed independently on the magnetic field data recorded by each satellite, enabling us to check the consistency of the results and thus to benchmark the method. The analysis is also extended to utilize the dual magnetometer measurements for determination of the event speed and size (which for a single spacecraft requires use of three-dimensional plasma velocity data to obtain a deHoffmann-Teller frame velocity) and for accommodating acceleration of the magnetopause normal to itself, which results in a curved spacecraft trajectory in the frame of reference moving with the disturbance. The analysis of the disturbance reveals that while its overall size is about 34,000 km in a direction parallel to the magnetopause but perpendicular to the event axis, the actual size of the bulge causing the field disturbance may have been as small as 9000 km with a dimension perpendicular to the magnetopause of the order of 1200 km. The bulge is found to be traveling at a speed of about 140 km/s toward the northern dawn quadrant of the dayside magnetopause. While plasma data from ISEE 2 provides evidence of plasma jetting, which suggests the event may be associated with reconnection, the orientation of the flux tube axis obtained from the analysis is significantly different from the expected reconnection line direction, A discussion of possible interpretations of this bulge orientation and motion is provided. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. UNIV CALIF LOS ANGELES,INST GEOPHYS & PLANETARY PHYS,LOS ANGELES,CA 90024. RP WALTHOUR, DW (reprint author), DARTMOUTH COLL,THAYER SCH ENGN,8000 CUMMINGS HALL,HANOVER,NH 03755, USA. OI Russell, Christopher/0000-0003-1639-8298 NR 14 TC 22 Z9 22 U1 0 U2 1 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1994 VL 99 IS A5 BP 8555 EP 8563 DI 10.1029/93JA03440 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NK217 UT WOS:A1994NK21700008 ER PT J AU HESSE, M BIRN, J AF HESSE, M BIRN, J TI MHD MODELING OF MAGNETOTAIL INSTABILITY FOR LOCALIZED RESISTIVITY SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID FIELD-ALIGNED CURRENTS; SUBSTORM CURRENT WEDGE; EXTENDED MAGNETOTAIL; CURRENT DIVERSION; BOUNDARY-LAYERS; RECONNECTION; SIMULATIONS; GENERATION; ORBIT; SHEET AB We present results of a three-dimensional MHD simulation of magnetotail evolution initiated by a sudden occurrence or increase of spatially localized resistivity as the major expected consequence of some localized microinstability. Because of the absense of a quantitative model, possible variations of resistivity levels with current density, or the reduction thereof, are not incorporated in the present investigation. The emphasis of the study is on an investigation of the changes to the overall evolution brought about by this localization, in particular, on the disruption and diversion of the cross-tail current and the nonlinear evolution of the magnetotail instability. The immediate consequences of the occurrence of the localized resistance and the resulting electric field are a reduction and diversion of the electric current around the region of high resistivity, associated with an increase of B(z) (''dipolarization'') at the earthward edge and a decrease of B(z) at the tailward edge of this region. These effects, however, are localized and do not involve a reduction of the total cross-tail current and hence do not lead to the global development of a ''substorm current wedge,'' which includes not only the reduction of the cross-tail current but also the buildup of a global field-aligned current system of ''region 1'' type (toward the Earth on the dawnside and away on the duskside of the tail). Such signatures develop at a later time, as consequences of a three-dimensional tearing instability, which is triggered by the occurrence of the resistivity. These features are found in combination with plasmoid formation and ejection, quite similar to results of earlier simulations with uniform resistivity. Differences are found in the timescale of the evolution, which tends to be shorter for localized resistivity, and in the propagation of the dipolarization effects in the equatorial plane. Whereas for uniform resistivity the temporal increase in B(z) tends to propagate tailward, apparently due to a pileup effect in the near-Earth region, an earthward propagation is found for the localized resistivity. This propagation results from an earthward convection of the gradient in B(z), which is set up by the reconnection process further tailward. C1 LOS ALAMOS NATL LAB,SPACE PLASMA PHYS GRP,LOS ALAMOS,NM 87545. RP HESSE, M (reprint author), NASA,GODDARD SPACE FLIGHT CTR,ELECTRODYNAM BRANCH,GREENBELT,MD 20771, USA. RI Hesse, Michael/D-2031-2012 NR 30 TC 29 Z9 29 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES JI J. Geophys. Res-Space Phys. PD MAY 1 PY 1994 VL 99 IS A5 BP 8565 EP 8576 DI 10.1029/94JA00441 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NK217 UT WOS:A1994NK21700009 ER PT J AU JENKINS, RA BUCHANAN, MV MERRIWEATHER, R ILGNER, RH GAYLE, TM WATSON, AP AF JENKINS, RA BUCHANAN, MV MERRIWEATHER, R ILGNER, RH GAYLE, TM WATSON, AP TI MOVEMENT OF CHEMICAL WARFARE AGENT SIMULANTS THROUGH POROUS-MEDIA SO JOURNAL OF HAZARDOUS MATERIALS LA English DT Article AB A measurement protocol is documented and data presented to characterize the permeation of chemical warfare agent simulants through the porous construction materials brick, cinder block, gypsum wall board, and wood. These data will be used to develop guidelines for access ('reentry') to potentially contaminated properties if nerve or vesicant agents are released during any phase of the US Department of the Army's Chemical Stockpile Disposal Program. A novel permeation cell design allowed sampling of air volumes adjacent to the spiked face, breakthrough, face and lateral face of each test medium at two temperatures. Simulant movement through wood is nearly always in the direction of the wood grain. Two-dimensional breakthrough was observed in brick and gypsum wall board. The sulfur mustard simulant broke through all test media in less than 60 min; nerve agent simulant breakthrough required several hours. Surface decontamination of wood with high test hypochlorite is 95% effective. C1 OAK RIDGE NATL LAB,DIV INSTRUMENTAT & CONTROLS,OAK RIDGE,TN 37831. OAK RIDGE NATL LAB,DIV HLTH SCI RES,OAK RIDGE,TN 37831. RP JENKINS, RA (reprint author), OAK RIDGE NATL LAB,DIV ANALYT CHEM,BLDG 4500S,MS-6120,POB 2008,OAK RIDGE,TN 37831, USA. RI Buchanan, Michelle/J-1562-2016 OI Buchanan, Michelle/0000-0002-8078-4575 NR 16 TC 7 Z9 7 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3894 J9 J HAZARD MATER JI J. Hazard. Mater. PD MAY PY 1994 VL 37 IS 2 BP 303 EP 325 DI 10.1016/0304-3894(93)E0106-C PG 23 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA NN532 UT WOS:A1994NN53200006 ER PT J AU KUTSCHER, CF AF KUTSCHER, CF TI HEAT-EXCHANGE EFFECTIVENESS AND PRESSURE-DROP FOR AIR-FLOW THROUGH PERFORATED PLATES WITH AND WITHOUT CROSSWIND SO JOURNAL OF HEAT TRANSFER-TRANSACTIONS OF THE ASME LA English DT Article AB Low-porosity perforated plates are being used as absorbers for heating ambient air in a new type of unglazed solar collector. This paper investigates the convective heat transfer effectiveness for low-speed air flow through thin, isothermal perforated plates with and without a crosswind on the upstream face. The objective of this work is to provide information that will allow designers to optimize hole size and spacing. In order to obtain performance data, a wind tunnel and small lamp array were designed and built. Experimental data were taken for a range of plate porosities from 0.1 to 5 percent, hole Reynolds numbers from 100 to 2000, and wind speeds from 0 to 4 m/s. Correlations were developed for heat exchange effectiveness and also for pressure drop. Infrared thermography was used to visualize the heat transfer taking place at the surface. RP KUTSCHER, CF (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 7 TC 46 Z9 47 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0022-1481 J9 J HEAT TRANS-T ASME JI J. Heat Transf.-Trans. ASME PD MAY PY 1994 VL 116 IS 2 BP 391 EP 399 DI 10.1115/1.2911411 PG 9 WC Thermodynamics; Engineering, Mechanical SC Thermodynamics; Engineering GA NP562 UT WOS:A1994NP56200014 ER PT J AU WANG, YS BYRD, CS BARLAZ, MA AF WANG, YS BYRD, CS BARLAZ, MA TI ANAEROBIC BIODEGRADABILITY OF CELLULOSE AND HEMICELLULOSE IN EXCAVATED REFUSE SAMPLES USING A BIOCHEMICAL METHANE POTENTIAL ASSAY SO JOURNAL OF INDUSTRIAL MICROBIOLOGY LA English DT Article DE ANAEROBIC; BIODEGRADATION; CELLULOSE; LANDFILLS; MUNICIPAL SOLID WASTE; METHANE ID LANDFILL; LIGNIN; DIGESTIBILITY; WOOD AB Improved techniques are needed to predict potential methane generation from refuse buried in landfills. The Biochemical Methane Potential (BMP) test was used to measure the methane potential of ten refuse samples excavated from a Berkeley, CA, landfill. The test was conducted in 125-ml serum bottles containing phosphate-buffered medium and inoculated with anaerobically digested sewage sludge. Comparison of the measured BMP to the theoretical BMP calculated from measured cellulose and hemicellulose concentrations indicated that cellulose plus hemicellulose is not well correlated with the measured BMP. The average of the measured to theoretical BMP was 19.1% (range 0-53%, s.d. = 16.9%). Measured sulfate concentrations showed that sulfate was an insignificant electron sink in the samples tested. Once methane production from the refuse was complete, 0.072 g of Whatman no. 1 filter paper was added to two of the four serum bottles incubated for each sample. An average of 84.9% (s.d. = 2.5%) of the added filter paper was recovered as methane, suggesting that some cellulose and hemicellulose present in refuse is recalcitrant or otherwise not bioavailable. C1 N CAROLINA STATE UNIV,DEPT CIVIL ENGN,BOX 7908,RALEIGH,NC 27695. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. NR 28 TC 63 Z9 64 U1 4 U2 26 PU STOCKTON PRESS PI BASINGSTOKE PA HOUNDMILLS, BASINGSTOKE, HAMPSHIRE, ENGLAND RG21 6XS SN 0169-4146 J9 J IND MICROBIOL JI J. Indust. Microbiol. PD MAY PY 1994 VL 13 IS 3 BP 147 EP 153 DI 10.1007/BF01583999 PG 7 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA PR147 UT WOS:A1994PR14700003 PM 7764843 ER PT J AU VANBELKUM, A MELCHERS, W DEPAUW, BE SCHERER, S QUINT, W MEIS, JF AF VANBELKUM, A MELCHERS, W DEPAUW, BE SCHERER, S QUINT, W MEIS, JF TI GENOTYPIC CHARACTERIZATION OF SEQUENTIAL CANDIDA-ALBICANS ISOLATES FROM FLUCONAZOLE-TREATED NEUTROPENIC PATIENTS SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID POLYMERASE CHAIN-REACTION; GENETIC SIMILARITY; RESISTANT CANDIDA; TYPING METHODS; AIDS PATIENTS; DNA PROBE; STRAINS; IDENTIFICATION; EPIDEMIOLOGY; SEQUENCES AB A polymerase chain reaction (PCR)-mediated genotyping assay for Candida albicans has been developed. By amplification of genomic regions bordered by eukaryotic or prokaryotic repeat-like motifs, differences between C. albicans isolates can be determined. The resolution of this typing procedure is at least as good as that of other genotypic assays. To ascertain the epidemiologic and clinical usefulness of this PCR genotyping, a retrospective analysis of serial C. albicans isolates from neutropenic adults treated with fluconazole was done. By PCR genotyping, 40 strains were detected in 24 patients. Eighteen C. albicans strains were found on multiple samplings in individual patients. It appears that most patients remain colonized with a C. albicans strain of constant genotypic characteristics. However, exceptions were observed. In 7 (29%) of 24 patients, strains deviating from the most frequently encountered type could be identified. All but 1 strain remained susceptible to fluconazole in vitro after treatment in vivo. It was not possible to demonstrate a relation of genotypic variation and antifungal susceptibility changes. C1 REINIER GRAAF GASTHUIS,CTR DIAGNOST,DEPT MOLEC BIOL,DELFT,NETHERLANDS. UNIV NIJMEGEN HOSP,DEPT MED MICROBIOL,NIJMEGEN,NETHERLANDS. UNIV NIJMEGEN HOSP,DEPT HEMATOL,NIJMEGEN,NETHERLANDS. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,CTR HUMAN GENOME,BERKELEY,CA 94720. RI Meis, Jacques/A-9241-2010; Melchers, Willem/C-8819-2015 OI Meis, Jacques/0000-0003-3253-6080; Melchers, Willem/0000-0002-5446-2230 FU NIAID NIH HHS [AI-23850] NR 37 TC 59 Z9 59 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0022-1899 J9 J INFECT DIS JI J. Infect. Dis. PD MAY PY 1994 VL 169 IS 5 BP 1062 EP 1070 PG 9 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA NW346 UT WOS:A1994NW34600018 PM 8169392 ER PT J AU LEE, TC FITZGERALD, V CHATTERJEE, R MALONE, B SNYDER, F AF LEE, TC FITZGERALD, V CHATTERJEE, R MALONE, B SNYDER, F TI DIFFERENTIATION-INDUCED INCREASE OF PLATELET-ACTIVATING-FACTOR ACETYLHYDROLASE IN HL-60 CELLS SO JOURNAL OF LIPID MEDIATORS AND CELL SIGNALLING LA English DT Article DE PLATELET-ACTIVATING FACTOR; ACETYLHYDROLASE; HL-60 CELLS ID FACTOR PAF ACETYLHYDROLASE; DENSITY LIPOPROTEIN; PLASMA; 1-ALKYL-2-ACETYL-SN-GLYCERO-3-PHOSPHOCHOLINE; PHOSPHOLIPASE-A2; PURIFICATION; DEGRADATION; DISEASE; LINE; ACETYLTRANSFERASE AB Platelet-activating factor (PAF) acetylhydrolase catalyzes the conversion of PAF to lyso-PAF and acetate. In this study we show that induced cellular differentiation of HL-60 cells grown in chemically defined media by dimethylsulfoxide (DMSO) to granulocytic cells increases the acetylhydrolase activity with a concomitant increased secretion of the enzyme into the media. This increase in acetylhydrolase activity is blocked by the presence of actinomycin D (1 mu M) or cycloheximide (1-2 mu M) in the culture media. Acetylhydrolase is located both in the cytosolic and particulate fractions; the relative distribution of acetylhydrolase activity in the particulate fraction and cytosol increases and decreases respectively, as the differentiation progresses. The addition of an intracellular protein transport inhibitor, monensin, causes furl,her accumulation of acetylhydrolase activity in the particulate fraction and a decrease in the media, with no effect on the acetylhydrolase activity in the cytosol. Acetylhydrolase in differentiated HL-60 cells acquires properties similar to those of the plasma acetylhydrolase in that it becomes less sensitive to 5,5'-dithiobis-2-nitrobenzoic acid and p-bromophenacylbromide inhibition than the acetylhydrolase in undifferentiated cells. The acetylhydrolase secreted into the media by the differentiated cells was almost totally insensitive to these inhibitors, whereas the acetylhydrolase from the particulate fraction gave an intermediate response; the cytosolic acetylhydrolase was sensitive to bath inhibitors. However, the acetylhydrolase secreted by differentiated HL-60 cells has a different electrophoretic mobility, temperature sensitivity, and association with lipoproteins when compared to that of human plasma acetylhydrolase. Collectively, these results indicate cellular differentiation induces intracellular acetylhydrolase activity through a mechanism involving both transcriptional and translational events. Furthermore, the acetylhydrolase synthesized during the DMSO-induced differentiation of HL-60 cells is then secreted into the media via the intracellular membrane transport system for proteins. Based on results obtained with HL-60 cells as a cell model, it is likely that more than one isoform of acetylhydrolase exists in the extracellular milieu. RP LEE, TC (reprint author), OAK RIDGE ASSOCIATED UNIV,INST SCI & EDUC,DIV MED SCI,POB 117,OAK RIDGE,TN 37831, USA. FU NHLBI NIH HHS [HL27109-13A1, HL35495-07A1]; NIDDK NIH HHS [R01 DK42804-03A1] NR 42 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0929-7855 J9 J LIPID MEDIAT CELL JI J. Lipid Mediat. Cell Signal. PD MAY PY 1994 VL 9 IS 3 BP 267 EP 283 PG 17 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA NU190 UT WOS:A1994NU19000009 PM 7921786 ER PT J AU JILES, DC THOELKE, JB AF JILES, DC THOELKE, JB TI THEORETICAL MODELING OF THE EFFECTS OF ANISOTROPY AND STRESS ON THE MAGNETIZATION AND MAGNETOSTRICTION OF TB0.3DY0.7FE2 SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article ID SINGLE-CRYSTALS; TERFENOL-D AB The alloy Tb0.3Dy0.7Fe2 is known to have a useful combination of high magnetostriction and low anisotropy energy. This means that relatively high strain amplitudes, exceeding 1 X 10(-3), can be obtained at low to moderate field strengths of less than 240 kA/m. This paper is concerned with the application of the anisotropic rotation model of the magnetization mechanism in this material. The model comprises the underlying assumptions which correspond to the Stoner-Wohlfarth model and its derivatives. In this case, the magnetic moments of the domains are constrained by the anisotropy to lie along the [111] directions within the crystal. It is shown from symmetry considerations that the fractional occupancies of six of the eight [111] directions exhibit pair degeneracy, leaving only five independent parameters to describe the distribution of domains among those directions. The changes in magnetization and magnetostriction which occur as the material is magnetized by a field along the [112] axis were determined both under zero stress and under a range of uniaxial stress levels applied along the [112] axis by following the changes in direction of the local minima in the sum of anisotropy, field and magnetostrictive energies. RP JILES, DC (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. RI Jiles, David/H-9548-2012 NR 24 TC 86 Z9 89 U1 1 U2 25 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD MAY PY 1994 VL 134 IS 1 BP 143 EP 160 DI 10.1016/0304-8853(94)90086-8 PG 18 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA NP957 UT WOS:A1994NP95700022 ER PT J AU GINLEY, DS BARR, L ASHBY, CIH PLUT, TA UREA, D SIEGAL, MP MARTENS, JS JOHANSSON, ME AF GINLEY, DS BARR, L ASHBY, CIH PLUT, TA UREA, D SIEGAL, MP MARTENS, JS JOHANSSON, ME TI DI-CARBOXYLIC-ACID-BASED AND TRI-CARBOXYLIC-ACID-BASED ETCHES FOR PROCESSING HIGH-TEMPERATURE SUPERCONDUCTING THIN-FILMS AND RELATED MATERIALS SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID YBA2CU3O7-X; PASSIVATION AB The development of passive and active electronics from high-temperature superconducting thin films depends on the development of process technology capable of producing appropriate feature sizes without degrading the key superconducting properties. We present a new class of chelating etches based on di- and tri-carboxylic acids that are compatible with positive photoresists and can produce submicron feature sizes while typically producing increases in the microwave surface resistance at 94 GHz by less than 10%. This simple etching process works well for both the Y-Ba-Cu-O and Tl-Ba-Ca-Cu-O systems. In addition, we demonstrate that the use of chelating etches with an activator such as HF allows the etching of related oxides such as LaAlO3, which is a key substrate material, and Pb(Zr0.53Ti0.47)O3 (PZT) which is a key ferroelectric material for HTS and other applications such as nonvolatile memories. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. CONDUCTUS,SUNNYVALE,CA 94086. RP GINLEY, DS (reprint author), NATL RENEWABLE LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 26 TC 5 Z9 5 U1 1 U2 1 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1994 VL 9 IS 5 BP 1126 EP 1133 DI 10.1557/JMR.1994.1126 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA NH285 UT WOS:A1994NH28500010 ER PT J AU ZEUCH, DH MONTGOMERY, ST KECK, JD AF ZEUCH, DH MONTGOMERY, ST KECK, JD TI FURTHER OBSERVATIONS ON THE EFFECTS OF NONHYDROSTATIC COMPRESSION ON THE FR1-]A0 POLYMORPHIC PHASE-TRANSFORMATION IN NIOBIUM-DOPED, LEAD-ZIRCONATE-TITANATE CERAMIC SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID SOLID-SOLUTION SYSTEM; THERMODYNAMIC THEORY; STRESS AB We recently performed a series of experiments on Nb-doped lead-zirconate-titanate ceramic to investigate the influence of constant shear stresses on the displacive, first-order rhombohedral/ferroelectric --> orthorhombic/antiferroelectric polymorphic transformation. In a previous paper and report we demonstrated that increasing shear stresses lowers the mean stress and confining pressure at which the transformation occurs, but we did not identify a criterion by which the transformation could be predicted to take place under nonhydrostatic stress. In this paper we use the dielectric anomaly which accompanies the transformation as an indicator of onset of the transition, and correct for the effects of high-pressure-seal friction on measurement of the maximum compressive stress applied to the test specimens during deviatoric loading. We show that a convincing case can be made that the transformation occurs when the maximum compressive stress equals the hydrostatic pressure at which the transformation would otherwise occur. RP ZEUCH, DH (reprint author), SANDIA NATL LABS,POB 5800,ALBUQUERQUE,NM 87185, USA. NR 15 TC 4 Z9 4 U1 1 U2 3 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD MAY PY 1994 VL 9 IS 5 BP 1322 EP 1327 DI 10.1557/JMR.1994.1322 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA NH285 UT WOS:A1994NH28500034 ER PT J AU TURNER, L TIOURIRINE, TN LAU, AWC AF TURNER, L TIOURIRINE, TN LAU, AWC TI COMPRESSIONAL OSCILLATION FREQUENCY OF AN ANHARMONIC-OSCILLATOR - THE SPHERICAL NONNEUTRAL PLASMA SO JOURNAL OF MATHEMATICAL PHYSICS LA English DT Article AB The physics of ultrahigh density compressional oscillations of a non-neutral plasma has already been discussed. Here, one technical facet will be analytically plumbed; namely the frequency of such oscillations. These oscillations are governed by differential equations whose solutions involve elliptic integrals of the third kind. Nevertheless, without studying the properties of these integrals, a procedure is demonstrated which permits the development of an analytic formula for the frequency of these anharmonic oscillations. This frequency is shown to be proportional to the cyclotron frequency omega(c) with a constant of proportionality that depends on the ratio of the difference between the radii of the outer and inner turning points divided by the sum of the radii of the two turning points. These radii, in turn, depend on two constants of integration that represent the energy of the compressional oscillations and the amount of charge in the plasma cloud. The final result of the analysis is that the frequency varies only from omega(c)/square-root 2 when the above ratio is small to (2/3)1/2omega(c) when the ratio is large. These limits are also obtained intuitively. RP TURNER, L (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0022-2488 J9 J MATH PHYS JI J. Math. Phys. PD MAY PY 1994 VL 35 IS 5 BP 2349 EP 2356 DI 10.1063/1.530557 PG 8 WC Physics, Mathematical SC Physics GA NJ533 UT WOS:A1994NJ53300023 ER PT J AU RADFORD, HE MOORE, MA SEARS, TJ GRUSSDORF, J NOLTE, J TEMPS, F AF RADFORD, HE MOORE, MA SEARS, TJ GRUSSDORF, J NOLTE, J TEMPS, F TI FAR-INFRARED LASER MAGNETIC-RESONANCE OF (X)OVER-TILDE-(2) A'-TRANS-DOCO SO JOURNAL OF MOLECULAR SPECTROSCOPY LA English DT Article ID TRANS-HOCO; SPECTRUM; DOCO; OH; CO AB Far-infrared laser magnetic resonance spectroscopy is used to measure components of 12 rotational transitions in the deuterated hydroxyformyl radical. Ten different FIR laser lines are employed at wavelengths between 339 and 663 mum. The assigned transitions are all b-dipole in character. The new data complement the previously reported a-dipole spectrum [Radford et al., J. Chem. Phys. 97, 3989-3995 (1992)] recorded in the millimeter-wave region. All of the existing high-resolution rotational spectra are subjected to a least-squares fit to the parameters appearing in the effective Hamiltonian describing the ground state of DOCO. The resulting parameters reproduce the existing spectroscopic observations to within the experimental accuracy and will be useful for predicting new spectra. The strongest resonances are well suited for future kinetics investigations of the radical. (C) 1994 Academic Press, Inc. C1 BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. MPI STROMUNGSFORSCH,D-37018 GOTTINGEN,GERMANY. RP RADFORD, HE (reprint author), HARVARD SMITHSONIAN CTR ASTROPHYS,60 GARDEN ST,CAMBRIDGE,MA 02138, USA. RI Sears, Trevor/B-5990-2013 OI Sears, Trevor/0000-0002-5559-0154 NR 21 TC 10 Z9 10 U1 2 U2 4 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0022-2852 J9 J MOL SPECTROSC JI J. Mol. Spectrosc. PD MAY PY 1994 VL 165 IS 1 BP 137 EP 149 DI 10.1006/jmsp.1994.1116 PG 13 WC Physics, Atomic, Molecular & Chemical; Spectroscopy SC Physics; Spectroscopy GA NH311 UT WOS:A1994NH31100010 ER PT J AU SEIBYL, JP WALLACE, E SMITH, EO STABIN, M BALDWIN, RM ZOGHBI, S ZEAPONCE, Y GAO, Y ZHANG, WY NEUMEYER, JL ZUBAL, IG CHARNEY, DS HOFFER, PB INNIS, RB AF SEIBYL, JP WALLACE, E SMITH, EO STABIN, M BALDWIN, RM ZOGHBI, S ZEAPONCE, Y GAO, Y ZHANG, WY NEUMEYER, JL ZUBAL, IG CHARNEY, DS HOFFER, PB INNIS, RB TI WHOLE-BODY BIODISTRIBUTION, RADIATION ABSORBED DOSE AND BRAIN SPECT IMAGING WITH IODINE-123-BETA-CIT IN HEALTHY-HUMAN SUBJECTS SO JOURNAL OF NUCLEAR MEDICINE LA English DT Article DE IODINE-123-BETA-CIT; BIODISTRIBUTION; SPECT; MONOAMINE TRANSPORTER; DOSIMETRY ID MONOAMINE REUPTAKE SITES; BINDING-SITES; PRIMATE BRAIN; I-125 RTI-55; DOPAMINE; TRANSPORTERS AB SPECT imaging with I-123-labeled methyl 3 beta-(4-iodophenyl)tropane-2 beta-carboxylate ([I-123]beta-CIT) in nonhuman primates has shown brain striatal activity, which primarily reflects binding to the dopamine transporter. The biodistribution and calculated radiation-absorbed doses of [I-123]beta-CIT administered to eight healthy subjects were measured with attention to the accurate determination of organ time-activity data. Methods: Whole-body transmission images were obtained with a scanning line source for attenuation correction of the emission images. Following administration of 92.5+/-22.2 MBq (2.5+/-0.6 mCi) of [I-123]beta-CIT, subjects were imaged with a whole-body imager every 30 min for 3 hr, every 60 min for the next 3 hr and at 12, 24 and 48 hr postinjection. Regional body conjugate counts were converted to microcuries of activity, with a calibration factor determined in a separate experiment using a distributed source of I-123. Results: The peak brain uptake represented 14% of the injected dose, with 2% of the activity approximately overlying the striatal region. Highest radiation-absorbed doses were to the lung (0.1 mGy/ MBq, 0.38 rads/mCi), liver (0.087 mGy/MBq, 0.32 rads/mCi) and lower large intestine (0.053 mGy/MBq, 0.20 rads/mCi). Conclusions: Iodine-123-beta-CIT is a promising SPECT agent for imaging of the dopamine transporter in humans with favorable dosimetry and high brain uptake. C1 YALE UNIV,SCH MED,DEPT PSYCHIAT,NEW HAVEN,CT. YALE UNIV,SCH MED,DEPT DIAGNOST RADIOL,NEW HAVEN,CT 06510. RES BIOCHEM INT,NATICK,MA. OAK RIDGE INST SCI & EDUC,OAK RIDGE,TN. RP SEIBYL, JP (reprint author), W HAVEN VA MED CTR 116A2,PSYCHIAT SERV,950 CAMPBELL AVE,W HAVEN,CT 06516, USA. FU NIMH NIH HHS [NIMH R43-MH48243] NR 18 TC 53 Z9 54 U1 1 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 BP 764 EP 770 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK514 UT WOS:A1994NK51400010 PM 8176456 ER PT J AU WATSON, E STABIN, M STUBBS, J AF WATSON, E STABIN, M STUBBS, J TI DOSIMETRY OF TECHNETIUM-94M-TEBOROXIME SO JOURNAL OF NUCLEAR MEDICINE LA English DT Letter RP WATSON, E (reprint author), OAK RIDGE INST SCI & EDUC,RADIAT INTERNAL DOSE INFORMAT CTR,OAK RIDGE,TN, USA. NR 5 TC 3 Z9 3 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 BP 923 EP 924 PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK514 UT WOS:A1994NK51400041 PM 8176485 ER PT J AU ATKINS, HL MAUSNER, LF MEINKEN, GE SRIVASTAVA, SC KLOPPER, JF CABAHUG, CJ FRANCESCHI, D MADAJEWICZ, S MEEK, AG LAU, YH PARK, TL WEBER, DA DALESSANDRO, T ANTAR, MA PYATT, BE AF ATKINS, HL MAUSNER, LF MEINKEN, GE SRIVASTAVA, SC KLOPPER, JF CABAHUG, CJ FRANCESCHI, D MADAJEWICZ, S MEEK, AG LAU, YH PARK, TL WEBER, DA DALESSANDRO, T ANTAR, MA PYATT, BE TI PALLIATION OF BONE PAIN WITH SN-117M(4+)DTPA SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. SUNY STONY BROOK,STONY BROOK,NY 11794. VET ADM MED CTR,NORTHPORT,NY 11768. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P37 EP P37 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900138 ER PT J AU CHATAL, JF GESTIN, JF FAIVRECHAUVET, A MEASE, RC MEINKEN, G SRIVASTAVA, SC AF CHATAL, JF GESTIN, JF FAIVRECHAUVET, A MEASE, RC MEINKEN, G SRIVASTAVA, SC TI CLINICAL-EVALUATION OF 2 NEW BIFUNCTIONAL CHELATING-AGENTS FOR IMMUNOSCINTIGRAPHY (IS) WITH INDIUM-111-ANTI-CEA MOLOCLONAL ANTIBODY SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 INSERM,RES UNIT 211,NANTES,FRANCE. BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973. RI GESTIN, Jean-Francois/M-1505-2015 NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P12 EP P12 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900037 ER PT J AU DING, YS FOWLER, JS VOLKOW, ND LOGAN, J DEWEY, S GATLEY, SJ ALEXOFF, D SUGANO, Y WOLF, AP AF DING, YS FOWLER, JS VOLKOW, ND LOGAN, J DEWEY, S GATLEY, SJ ALEXOFF, D SUGANO, Y WOLF, AP TI SYNTHESIS AND EVALUATION OF THE RACEMATE AND INDIVIDUAL ENANTIOMERS OF C-11 LABELED METHYLPHENIDATE AS RADIOLIGANDS FOR THE PRESYNAPTIC DOPAMINERGIC NEURON SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P129 EP P129 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900517 ER PT J AU DING, YS REHDER, K VASSELLO, M FOWLER, JS WOLF, AP AF DING, YS REHDER, K VASSELLO, M FOWLER, JS WOLF, AP TI SYNTHESIS OF [C-11] RO-19-6327, A HIGHLY SELECTIVE AND REVERSIBLE MONOAMINE-OXIDASE-B INHIBITOR POTENTIALLY USEFUL FOR TREATMENT OF PARKINSONS-DISEASE SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P7 EP P7 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900016 ER PT J AU ECKERMANN, KF STABIN, MG AF ECKERMANN, KF STABIN, MG TI CONVERSION FACTORS MOR MARROW AND BONE BY SKELETAL REGIONS SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 OAK RIDGE NATL LAB,OAK RIDGE,TN. OAK RIDGE INST SCI & EDUC,OAK RIDGE,TN. NR 0 TC 3 Z9 3 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P112 EP P112 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900445 ER PT J AU FERRIERI, RA FOWLER, JS WOLF, AP AF FERRIERI, RA FOWLER, JS WOLF, AP TI MODEL STUDIES USING SUPERCRITICAL CARBON-DIOXIDE FLUID (SF CO2) AS A REACTION MEDIUM FOR RADIOTRACER SYNTHESIS AND PURIFICATION SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 1 Z9 1 U1 1 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P42 EP P42 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900161 ER PT J AU FIROUZBAKHT, ML SCHLYER, DJ WOLF, AP AF FIROUZBAKHT, ML SCHLYER, DJ WOLF, AP TI A ROUTINE PRODUCTION SYSTEM FOR F-18 FROM FROZEN O-18 ENRICHED CARBON-DIOXIDE SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P253 EP P253 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90901040 ER PT J AU GATLEY, SJ FOWLER, JS DEWEY, SL SCHLYER, DJ SHEA, CE MACGREGOR, RR LOGAN, J VOLKOW, ND WOLF, AP AF GATLEY, SJ FOWLER, JS DEWEY, SL SCHLYER, DJ SHEA, CE MACGREGOR, RR LOGAN, J VOLKOW, ND WOLF, AP TI PET STUDIES WITH LOW AND HIGH-AFFINITY DOPAMINE D2 RECEPTOR RADIOLIGANDS - EFFECTS OF 4-HYDROXYBUTYRATE (4HB) SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P140 EP P141 PG 2 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900566 ER PT J AU GULLBERG, GT HUESMAN, RH ZENG, GL SMITH, AM AF GULLBERG, GT HUESMAN, RH ZENG, GL SMITH, AM TI EFFICIENT ESTIMATION OF DYNAMIC CARDIAC SPECT KINETIC-PARAMETERS USING SINGULAR-VALUE DECOMPOSITION RECONSTRUCTION SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 UNIV UTAH,SALT LAKE CITY,UT. UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA. NR 0 TC 1 Z9 1 U1 0 U2 2 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P18 EP P18 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900062 ER PT J AU HUESMAN, RH KLEIN, GJ BUDINGER, TF AF HUESMAN, RH KLEIN, GJ BUDINGER, TF TI STATISTICAL CORRELATIONS IN A PET TIME-ACTIVITY CURVE DUE TO ATTENUATION CORRECTION SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 LAWRENCE BERKELEY LAB,BERKELEY,CA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P183 EP P183 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900738 ER PT J AU IVANOVIC, M ESSER, PD VANHEERTUM, RL WEBER, DA AF IVANOVIC, M ESSER, PD VANHEERTUM, RL WEBER, DA TI EVALUATION OF LESION DETECTABILITY AND CROSSTALK CORRECTION METHODS IN DUAL RADIONUCLIDE IMAGING SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. COLUMBIA UNIV,NEW YORK,NY 10027. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P61 EP P61 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900237 ER PT J AU JOSHI, V SRIVASTAVA, SC MEINKEN, GE MEASE, RC PYATT, B MAUSNER, LF STEPLEWSKI, Z AF JOSHI, V SRIVASTAVA, SC MEINKEN, GE MEASE, RC PYATT, B MAUSNER, LF STEPLEWSKI, Z TI A COMPARATIVE-STUDY OF CO-57 LABELED 4-ICE AND 4-BACE IMMUNOCONJUGATES - EFFECT OF CONJUGATION METHOD AND ANTIBODY/TUMOR MODEL SYSTEM ON BIODISTRIBUTION SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973. WISTAR INST ANAT & BIOL,PHILADELPHIA,PA 19104. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P30 EP P30 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900111 ER PT J AU KOLSKY, KL JOSHI, V MEINKEN, GE SWEET, M MAUSNER, LF SRIVASTAVA, SC AF KOLSKY, KL JOSHI, V MEINKEN, GE SWEET, M MAUSNER, LF SRIVASTAVA, SC TI IMPROVED PRODUCTION, AND EVALUATION, OF CU-67 FOR TUMOR RADIOIMMUNOTHERAPY SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973. NR 1 TC 3 Z9 3 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P259 EP P259 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90901066 ER PT J AU MCPHERSON, DW LAMBERT, CR ZEEBERG, B SOOD, V MCREE, RC REBA, R KNAPP, FF AF MCPHERSON, DW LAMBERT, CR ZEEBERG, B SOOD, V MCREE, RC REBA, R KNAPP, FF TI EFFECTS OF ABSOLUTE-CONFIGURATION OF IQNP ON MUSCARINIC RECEPTOR SUBTYPE SELECTIVITY IN-VITRO AND IN-VIVO SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 OAK RIDGE NATL LAB,NUCL MED GRP,OAK RIDGE,TN. GEORGE WASHINGTON UNIV,WASHINGTON,DC. UNIV CHICAGO,CHICAGO,IL 60637. RI Sood, Vinay/B-7109-2008 NR 0 TC 4 Z9 4 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P93 EP P93 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900368 ER PT J AU MEINKEN, GE MAUSNER, LF ATKINS, HL PYATT, B SRIVASTAVA, SC AF MEINKEN, GE MAUSNER, LF ATKINS, HL PYATT, B SRIVASTAVA, SC TI MECHANISTIC STUDIES OF THE NEW BONE PAIN PALLIATION AGENT, SN-117M (4+)-DTPA SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P52 EP P52 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900203 ER PT J AU MIRZADEH, S ALEXANDER, CW KNAPP, FF AF MIRZADEH, S ALEXANDER, CW KNAPP, FF TI THE ADVANCED NEUTRON SOURCE (ANS) - A PROPOSED NATIONAL RESOURCE FOR MEDICAL RADIOISOTOPE PRODUCTION SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 OAK RIDGE NATL LAB,NUCL MED GRP,OAK RIDGE,TN. OAK RIDGE NATL LAB,DIV CHEM TECHNOL,OAK RIDGE,TN 37831. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P245 EP P245 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90901005 ER PT J AU MOZLEY, PD KIM, HJ MCELGIN, W STUBBS, JB AF MOZLEY, PD KIM, HJ MCELGIN, W STUBBS, JB TI QUANTIFYING THE SOURCES OF ERROR IN MEASUREMENTS OF URINE ACTIVITY SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 UNIV PENN,PHILADELPHIA,PA 19104. ORISE,OAK RIDGE,TN. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P157 EP P157 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900629 ER PT J AU PAN, D GATLEY, SJ DEWEY, SL CHEN, R ALEXOFF, D DING, YS FOWLER, JS VOLKOW, ND WOLF, AP AF PAN, D GATLEY, SJ DEWEY, SL CHEN, R ALEXOFF, D DING, YS FOWLER, JS VOLKOW, ND WOLF, AP TI BROMINATED AND RADIOIODINATED DERIVATIVES OF METHYLPHENIDATE (MP) - POTENTIAL IMAGING AGENTS FOR THE DOPAMINE (DA) TRANSPORTER SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P94 EP P94 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900372 ER PT J AU SALAKO, Q DENARDO, GL SHEN, S DENARDO, SJ MAUSNER, LF SRIVASTAVA, SC KUKIS, DL AF SALAKO, Q DENARDO, GL SHEN, S DENARDO, SJ MAUSNER, LF SRIVASTAVA, SC KUKIS, DL TI CONFRONTING THE PROBLEM OF CU-67 RADIATION MEASUREMENT IN THE PRESENCE OF CONTAMINATING CU-64 ISOTOPE, USING SIMPLE NUCLEAR-MEDICINE RADIOISOTOPE DOSE CALIBRATOR SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 UNIV CALIF DAVIS,INST MOLEC CANC,SACRAMENTO,CA. BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P244 EP P244 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90901000 ER PT J AU SCHLYER, DJ DEWEY, SL AF SCHLYER, DJ DEWEY, SL TI CORRECTION OF AN INPUT FUNCTION FOR ERRORS INTRODUCED WITH AUTOMATED BLOOD-SAMPLING SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P128 EP P128 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900513 ER PT J AU SGOUROS, G STABIN, MG JUREIDINI, IM SCOTT, AS GRAHAM, MC LARSON, SM SCHEINBERG, DA ECKERMAN, KF AF SGOUROS, G STABIN, MG JUREIDINI, IM SCOTT, AS GRAHAM, MC LARSON, SM SCHEINBERG, DA ECKERMAN, KF TI CLINICAL IMPLEMENTATION OF NEW REGION-SPECIFIC S-VALUES FOR MARROW DOSIMETRY - DOSE DISTRIBUTION VS MEAN MARROW DOSE IN RADIOIMMUNOTHERAPY OF LEUKEMIA SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 MEM SLOAN KETTERING CANC CTR,NEW YORK,NY 10021. OAK RIDGE INST SCI & EDUC,OAK RIDGE,TN. OAK RIDGE NATL LAB,OAK RIDGE,TN. NR 0 TC 3 Z9 3 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P112 EP P112 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900446 ER PT J AU SMITH, GS DEWEY, SL LOGAN, J BRODIE, JD VITKUN, S SIMKOWITZ, P ALEXOFF, D FOWLER, JS VOLKOW, ND WOLF, AP AF SMITH, GS DEWEY, SL LOGAN, J BRODIE, JD VITKUN, S SIMKOWITZ, P ALEXOFF, D FOWLER, JS VOLKOW, ND WOLF, AP TI THE SEROTONIN-DOPAMINE INTERACTION MEASURED WITH POSITRON EMISSION TOMOGRAPHY (PET) AND C-11 RACLOPRIDE IN NORMAL HUMAN-SUBJECTS SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 NYU,SCH MED,DEPT PSYCHIAT,NEW YORK,NY. BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973. SUNY STONY BROOK,DEPT ANESTHESIOL,STONY BROOK,NY 11794. NR 0 TC 3 Z9 3 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P85 EP P85 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900335 ER PT J AU SOM, P WANG, GJ OSTER, ZH KNAPP, FF MCPHERSON, DW YOUSEF, K CABAHUG, C AF SOM, P WANG, GJ OSTER, ZH KNAPP, FF MCPHERSON, DW YOUSEF, K CABAHUG, C TI QUANTITATIVE ARG MICROIMAGING STUDIES OF 2 MUSCARINIC ANTAGONIST ISOMERS - BLOCKING AND THE EFFECTS OF COCAINE SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. SUNY STONY BROOK,STONY BROOK,NY 11794. OAK RIDGE NATL LAB,OAK RIDGE,TN. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P201 EP P201 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900812 ER PT J AU SPARKS, RB DEY, HM SEIBYL, IB INNIS, RB STUBBS, JB AF SPARKS, RB DEY, HM SEIBYL, IB INNIS, RB STUBBS, JB TI RADIATION-DOSE ESTIMATES FOR C-11 IOMAZENIL, A BENZODIAZEPINE RECEPTOR RADIOLIGAND SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 OAK RIDGE INST SCI & EDUC,OAK RIDGE,TN. YALE UNIV,VAMC,W HAVEN,CT. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P159 EP P159 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900636 ER PT J AU STABIN, MG BRODACK, JW DEUTSCH, KF AF STABIN, MG BRODACK, JW DEUTSCH, KF TI RADIATION-DOSIMETRY FOR INTRASYNOVIAL ADMINISTRATION OF SM-153 PARTICULATES SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 ORISE,OAK RIDGE,TN. MALLINCKRODT MED INC,ST LOUIS,MO. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P160 EP P160 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900639 ER PT J AU STABIN, MG STUBBS, JB AF STABIN, MG STUBBS, JB TI RADIATION-DOSE TO THE WALLS OF HOLLOW ORGANS SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 OAK RIDGE INST SCI & EDUC,OAK RIDGE,TN. NR 0 TC 0 Z9 0 U1 0 U2 1 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P78 EP P78 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900308 ER PT J AU TAN, P DEWEY, SL GATLEY, SJ PAPPAS, N MACGREGOR, R DING, YS SHEA, C ALEXOFF, D MARTIN, T JENKINS, D KING, P FOWLER, JS ASHBY, C WOLF, A AF TAN, P DEWEY, SL GATLEY, SJ PAPPAS, N MACGREGOR, R DING, YS SHEA, C ALEXOFF, D MARTIN, T JENKINS, D KING, P FOWLER, JS ASHBY, C WOLF, A TI DRUG PHARMACOKINETICS AND PHARMACODYNAMICS - PET AND MICRODIALYSIS STUDIES OF SR 46349B, SELECTIVE 5HT2 ANTAGONIST SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 6 Z9 6 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P67 EP P67 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900264 ER PT J AU VANBROCKLIN, HF ENAS, JD HANRAHAN, SM BRENNAN, KM ONEIL, JP TAYLOR, SE AF VANBROCKLIN, HF ENAS, JD HANRAHAN, SM BRENNAN, KM ONEIL, JP TAYLOR, SE TI [F-18] FLUORODIHYDROROTENONE - SYNTHESIS AND EVALUATION OF A MITOCHONDRIAL ELECTRON-TRANSPORT CHAIN (ETC) COMPLEX-I PROBE FOR PET SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,BERKELEY,CA. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P73 EP P73 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900288 ER PT J AU VOLKOW, ND FOWLER, JS LOGAN, J GATLEY, JS DEWEY, SL MACGREGOR, RR SCHLYER, DJ PAPPAS, N KING, P WOLF, AP AF VOLKOW, ND FOWLER, JS LOGAN, J GATLEY, JS DEWEY, SL MACGREGOR, RR SCHLYER, DJ PAPPAS, N KING, P WOLF, AP TI COMPARISON OF [11C]COCAINE BINDING AT TRACER AND PHARMACOLOGICAL DOSES IN BABOON BRAIN - A PET STUDY SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P130 EP P130 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900522 ER PT J AU VOLKOW, ND DING, YS FOWLER, JS WANG, GJ LOGAN, J DEWEY, S GATLEY, SJ ALEXOFF, D SALATA, C WOLF, AP AF VOLKOW, ND DING, YS FOWLER, JS WANG, GJ LOGAN, J DEWEY, S GATLEY, SJ ALEXOFF, D SALATA, C WOLF, AP TI PET MEASUREMENT OF C-11 METHYLPHENIDATE PHARMACOKINETICS AND DISTRIBUTION IN THE HUMAN BRAIN SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P85 EP P85 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900336 ER PT J AU WANG, GJ VOLKOW, ND LAU, YH FOWLER, JS MEEK, A PARK, T WONG, C ADLER, A WOLF, AP AF WANG, GJ VOLKOW, ND LAU, YH FOWLER, JS MEEK, A PARK, T WONG, C ADLER, A WOLF, AP TI REGIONAL BRAIN GLUCOSE-METABOLISM IN PATIENTS WITH BRAIN-TUMORS BEFORE AND AFTER RADIOTHERAPY SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. SUNY STONY BROOK,DEPT RADIAT ONCOL,STONY BROOK,NY 11794. NR 0 TC 1 Z9 1 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P213 EP P213 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900867 ER PT J AU WANG, GJ OSTER, ZH SOM, P POLLACK, W YOUSEF, K ZAMORA, PO RHODES, BA AF WANG, GJ OSTER, ZH SOM, P POLLACK, W YOUSEF, K ZAMORA, PO RHODES, BA TI TC-99M LABELED LAMININ DERIVED PEPTIDE, TF-99M-YIGSR FOR THROMBUS SPECIFIC IMAGING SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. SUNY STONY BROOK,STONY BROOK,NY 11794. RHOMED INC,ALBUQUERQUE,NM. NR 0 TC 0 Z9 0 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P106 EP P106 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900420 ER PT J AU WEBER, DA FRANCESCHI, D IVANOVIC, M FRANCESCHI, M ATKINS, H POPENOE, E STRAND, SE ERLANDSSON, K SUSSKIND, H AF WEBER, DA FRANCESCHI, D IVANOVIC, M FRANCESCHI, M ATKINS, H POPENOE, E STRAND, SE ERLANDSSON, K SUSSKIND, H TI TRACER LOCALIZATION IN INTRACEREBRAL GLIOSARCOMA SO JOURNAL OF NUCLEAR MEDICINE LA English DT Meeting Abstract C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. LUND UNIV,MED CTR,LUND,SWEDEN. SESTRE MILOSRDNICE,ZAGREB,CROATIA. SUNY STONY BROOK,STONY BROOK,NY 11794. NR 0 TC 2 Z9 2 U1 0 U2 0 PU SOC NUCLEAR MEDICINE INC PI RESTON PA 1850 SAMUEL MORSE DR, RESTON, VA 20190-5316 SN 0161-5505 J9 J NUCL MED JI J. Nucl. Med. PD MAY PY 1994 VL 35 IS 5 SU S BP P221 EP P221 PG 1 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NK909 UT WOS:A1994NK90900899 ER PT J AU HARGROVE, DM MORRIS, JG ROGERS, QR AF HARGROVE, DM MORRIS, JG ROGERS, QR TI KITTENS CHOOSE A HIGH LEUCINE DIET EVEN WHEN ISOLEUCINE AND VALINE ARE THE LIMITING AMINO-ACIDS SO JOURNAL OF NUTRITION LA English DT Article DE BRANCHED-CHAIN AMINO ACIDS; KITTENS; LEUCINE; DIETARY CHOICE ID FOOD-INTAKE; ANTAGONISM; CHICKS AB This study was conducted to determine the effect of excess leucine on the dietary choice of kittens. The basal diets contained 16% (low nitrogen) or 24% (adequate nitrogen) amino acids and were limiting in isoleucine and valine. The addition of leucine to either of these basal diets has been shown to cause a transitory adverse effect on the growth and food intake of kittens. In separate experiments each basal diet was used to test three sets of choices: basal vs. basal + 10% leucine; basal + alanine vs. basal + leucine (isonitrogenous) and basal vs. basal + alanine. When offered basal vs. basal + excess leucine, the kittens chose significantly more of the excess leucine diet regardless of the level of nitrogen in the basal diet. When offered an isonitrogenous choice of excess alanine vs. excess leucine, the kittens selected somewhat more of the excess leucine diets over the excess alanine diets; this selection was sustained longer in kittens fed low nitrogen. In the third choice experiment (basal vs. basal + alanine), the group offered the low nitrogen diets exhibited no preferences, and the group offered adequate-nitrogen diets selected significantly more of the excess alanine diet. These results for kittens are opposite to those for rats, a species that will select a low protein basal or even a protein-free diet over a diet containing excess leucine. C1 LAWRENCE LIVERMORE NATL LAB,SCH VET MED,DEPT MOLEC BIOSCI,DAVIS,CA 95616. NR 13 TC 4 Z9 4 U1 0 U2 0 PU AMER INST NUTRITION PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0022-3166 J9 J NUTR JI J. Nutr. PD MAY PY 1994 VL 124 IS 5 BP 689 EP 693 PG 5 WC Nutrition & Dietetics SC Nutrition & Dietetics GA NK245 UT WOS:A1994NK24500011 PM 8169660 ER PT J AU STEINBERG, FM GERSHWIN, ME RUCKER, RB AF STEINBERG, FM GERSHWIN, ME RUCKER, RB TI DIETARY PYRROLOQUINOLINE QUINONE - GROWTH AND IMMUNE-RESPONSE IN BALB/C MICE SO JOURNAL OF NUTRITION LA English DT Article DE PYRROLOQUINOLINE QUINONE; BALB/C MICE; MITOGEN RESPONSE; INTERLEUKIN PRODUCTION ID VITAMIN-E; NITROBLUE TETRAZOLIUM; QUINONE; DEFICIENCY; CELL; RAT; INTERLEUKINS; IGM AB Pyrroloquinoline quinone (PQQ) is proposed as a nutritionally important growth factor, and we provide evidence that PQQ improves reproduction performance in BALB/c mice and stimulates neonatal growth. In the first experiment, weanling female BALB/c mice were adapted to a chemically-defined diet containing 0, 100, 200, 300, 1000, or 5000 ng PQQ/g of diet. The mice were bred and their reproductive performance and surviving offspring were assessed for 20-wk. Reproductive outcome was markedly compromised for the groups most deprived of PQQ. Supplemented groups (greater than or equal to 1000 ng PQQ/g diet) had 8 pups/ litter compared with 4-5 pups/litter in the PQQ-deprived groups (less than or equal to 300 ng PQQ/g diet). Of the pups surviving to weaning, 8 of 10 survived when PQQ was added to the diet (greater than or equal to 300 ng PQQ/g diet) compared with 4 of 10 in the PQQ-deficient group. The apparent requirement for Paa for optimal growth of surviving neonates was estimated to be greater than or equal to 300 ng PQQ/g of diet. Moreover, splenic cell response to the mitogens concanavalin A and lipopolysaccharide, appeared related to PQQ intake. In a second experiment, female BALB/c mice were fed diets containing PQQ added at 0 or 1000 ng/g of diet, and interleukin 1 and 2 production were assessed. In particular, levels of interleukin 2, an autocrine and paracrine growth factor, were reduced in mice fed the deficient diet at a time when T-cell proliferation occurs in neonates. Results suggest that PQQ or similar compounds may play nutritionally important roles at critical stages in development. C1 LAWRENCE LIVERMORE NATL LAB,SCH MED,DEPT NUTR AGR & ENVIRONM SCI,DAVIS,CA 95616. LAWRENCE LIVERMORE NATL LAB,SCH MED,DEPT RHEUMATOL,DAVIS,CA 95616. FU NIDDK NIH HHS [DK 35747] NR 39 TC 59 Z9 64 U1 0 U2 4 PU AMER INST NUTRITION PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0022-3166 J9 J NUTR JI J. Nutr. PD MAY PY 1994 VL 124 IS 5 BP 744 EP 753 PG 10 WC Nutrition & Dietetics SC Nutrition & Dietetics GA NK245 UT WOS:A1994NK24500019 PM 8169668 ER PT J AU SMITH, AB GUENTHER, PT AF SMITH, AB GUENTHER, PT TI FAST-NEUTRON SCATTERING FROM VIBRATIONAL NUCLEI - RH-103 SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article ID OPTICAL-MODEL; STATE; CA-40 AB Neutron differential elastic- and inelastic-scattering cross sections of Rh-103 are measured for incident energies of approximately 1.5 to 10 MeV. The measurements are made with sufficient detail to well define the energy-averaged behaviour of the elastic-scattering process. Neutrons corresponding to excitations of groups of levels at 334 +/- 13, 536 +/- 10, 648 +/- 25, 796 +/- 20, 864 +/- 22, 1120 +/- 22, 1279 +/- 60, 1481 +/- 27 and 1683 +/- 39 keV are observed and the corresponding cross sections determined. Assuming the target nucleus is reasonably approximated by a simple one-phonon vibrator, spherical-optical, dispersive-optical, and coupled-channels models are deduced from the data base. Physical aspects of these models are compared with theoretical predictions and the systematics of similar model parametrizations in this mass-energy region. C1 UNIV ARIZONA,DEPT NUCL & ENERGY ENGN,TUCSON,AZ 85721. RP SMITH, AB (reprint author), ARGONNE NATL LAB,DIV ENGN PHYS,ARGONNE,IL 60439, USA. NR 41 TC 4 Z9 4 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD MAY PY 1994 VL 20 IS 5 BP 795 EP 810 DI 10.1088/0954-3899/20/5/013 PG 16 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA NM534 UT WOS:A1994NM53400013 ER PT J AU WARE, AG NITZEL, ME PAGE, JD AF WARE, AG NITZEL, ME PAGE, JD TI A SUMMARY OF NRC GENERIC SAFETY ISSUE-113 - DYNAMIC QUALIFICATION AND TESTING OF LARGE-BORE HYDRAULIC SNUBBERS SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB The Nuclear Regulatory Commission (NRC) developed Generic Safety Issue 113, ''Dynamic Qualification and Testing of Large Bore Hydraulic Snubbers (LBHSs),'' with the objective of evaluating the reliability of LBHS in operating commercial nuclear power plants. This paper provides a summary of the important findings of the Generic Safety Issue-113 research program and a discussion of the recommendations that were made in NUREG/CR-5416. Fifteen potential improvements in LBHS reliability were identified, covering the areas of design, environmental (including dynamic) qualification, functional testing, visual inspection, and personnel training. C1 US NUCL REGULATORY,WASHINGTON,DC 20555. RP WARE, AG (reprint author), EG&G IDAHO INC,IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415, USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD MAY PY 1994 VL 116 IS 2 BP 85 EP 95 DI 10.1115/1.2929581 PG 11 WC Engineering, Mechanical SC Engineering GA NP570 UT WOS:A1994NP57000001 ER PT J AU ROACH, DP PRIDDY, TG AF ROACH, DP PRIDDY, TG TI EFFECT OF MATERIAL PROPERTIES ON THE STRAIN TO FAILURE OF THICK-WALLED CYLINDERS SUBJECTED TO INTERNAL-PRESSURE SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB The determination of the fully plastic response and pressure limit of a pressure vessel is of considerable importance in design, especially in autofrettage considerations. This paper presents the results of an experimental study which measured the maximum internal pressure which can be applied to thick-walled cylindrical vessels. Both aluminum and steel, with material properties ranging from ductile to brittle, were tested at stress levels through plastic and strain hardening ranges to fracture. From these tests, the pressure-expansion and through-thickness yielding characteristics were determined for these specimens. It is shown that a strain-to-failure criterion, based on the triaxiality of stress in the critical region, can be used to predict the complete pressure versus strain relations and maximum pressure for these cylinders. A simple tension-true stress-strain relation of the material is employed to analytically predict the response of the cylinder into the plastic regime. Finally, simplified theoretical and empirical formulas for bursting pressures are checked against the experimental results. RP ROACH, DP (reprint author), SANDIA NATL LABS,DEPT EXPTL MECH,ALBUQUERQUE,NM 87185, USA. NR 15 TC 0 Z9 0 U1 1 U2 4 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD MAY PY 1994 VL 116 IS 2 BP 96 EP 104 DI 10.1115/1.2929582 PG 9 WC Engineering, Mechanical SC Engineering GA NP570 UT WOS:A1994NP57000002 ER PT J AU KEENEY, JA BASS, BR AF KEENEY, JA BASS, BR TI AN EVALUATION OF ANALYSIS METHODOLOGIES FOR PREDICTING CLEAVAGE ARREST OF A DEEP CRACK IN AN RPV SUBJECTED TO PTS LOADING CONDITIONS SO JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB Several calculational procedures are compared for predicting cleavage arrest of a deep crack in the wall of a prototypical reactor pressure vessel (RPV) subjected to pressurized-thermal-shock (PTS) types of loading conditions. Three procedures examined in this study utilized the following models: 1) a static finite-element model (full bending); 2) a radially constrained static model; and 3) a thermoelastic dynamic finite-element model. A PTS transient loading condition was selected that produced a deep arrest of an axially oriented initially shallow crack according to calculational results obtained from the static (full-bending) model. Results from the static models were compared with those generated from detailed thermoelastic dynamic finite-element analysis. The dynamic analyses modeled cleavage-crack propagation using a node-release technique and an application-mode methodology based on dynamic fracture toughness curves generated from measured data. Comparisons presented here indicate that the degree to which the dynamic solutions can be approximated by the static models is highly dependent on several factors, including the material dynamic fracture curves and the propensity for cleavage reinitiation of the arrested crack under PTS loading conditions. Additional work is required to develop and validate a satisfactory dynamic fracture toughness model applicable to postcleavage arrest conditions in an RPV. RP KEENEY, JA (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 24 TC 0 Z9 0 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0094-9930 J9 J PRESS VESS-T ASME JI J. Press. Vessel Technol.-Trans. ASME PD MAY PY 1994 VL 116 IS 2 BP 128 EP 135 DI 10.1115/1.2929566 PG 8 WC Engineering, Mechanical SC Engineering GA NP570 UT WOS:A1994NP57000007 ER PT J AU SLUTZ, SA GAUNTT, RO HARMS, GA LATHAM, T ROMAN, W RODGERS, RJ AF SLUTZ, SA GAUNTT, RO HARMS, GA LATHAM, T ROMAN, W RODGERS, RJ TI THERMAL-RADIATION IN GAS CORE NUCLEAR-REACTORS FOR SPACE PROPULSION SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB A diffusive model of the radial transport of thermal radiation out of a cylindrical core of fissioning plasma is presented. The diffusion approximation is appropriate because the opacity of uranium is very high at the temperatures of interest (>3000 K). We make one additional simplification of assuming constant opacity throughout the fuel. This allows the complete set of solutions to be expressed as a single function. This function is approximated analytically to facilitate parametric studies of the performance of a test module of the nuclear light bulb gas-core nuclear-rocket-engine concept, in the Annular Core Research Reactor at Sandia National Laboratories. Our findings indicate that radiation temperatures in range of 4000-6000 K are attainable, which is sufficient to test the high specific impulse potential (approximately 2000 s) of this concept. C1 UNITED TECHNOL RES CTR,PROC DIAGNOST LAB,E HARTFORD,CT 06108. UNITED TECHNOL RES CTR,FLUID MECH LAB,E HARTFORD,CT 06108. RP SLUTZ, SA (reprint author), SANDIA NATL LABS,DEPT ELECTROMAGNET THEORY,ALBUQUERQUE,NM 87185, USA. NR 15 TC 1 Z9 1 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 1994 VL 10 IS 3 BP 419 EP 424 DI 10.2514/3.23751 PG 6 WC Engineering, Aerospace SC Engineering GA NM077 UT WOS:A1994NM07700018 ER PT J AU MATTHEWS, RB COOMES, EP KHAN, EU AF MATTHEWS, RB COOMES, EP KHAN, EU TI HIERARCHICAL ANALYSIS OF OPTIONS FOR LUNAR-SURFACE POWER SO JOURNAL OF PROPULSION AND POWER LA English DT Article AB A decision analysis study was conducted to evaluate potential habitat power concepts for manned lunar-surface operations. The objectives of the study were to rank alternative lunar-surface power systems for the first lunar outpost (FLO). The six alternative power concepts evaluated are the following: photovoltaic with regenerative fuel cell (RFC) storage, solar dynamic with RFC storage, TOPAZ II and SP-100 space reactor systems, dynamic isotope power system (DIPS), and laser-beamed power. The analytical hierarchy decision-making process was used for the decision-making methodology. The process provides a systematic approach to managing complex decisions that involve numerous tradeoffs between alternative concepts and evaluation criteria. Safety, risk, performance, lifetime, supportability, special factors, and versatility were selected as the major evaluation criteria. Based on the available information, DIPS was the power system of choice for a 45-day, 12-kWe FLO mission because of its favorable combination of ranking and cost. When launch costs were not considered, the photovoltaic system with RFC storage ranked first. The results of this study reflect the best judgments of the working group, given the set of requirements, the agreed-on set of selection criteria, and the best available concept information. C1 PACIFIC NW LAB, DEPT ENERGY & SCI, RICHLAND, WA 99352 USA. US DOE, DIV ENERGY RES, OFF SPACE, WASHINGTON, DC 20585 USA. RP MATTHEWS, RB (reprint author), LOS ALAMOS NATL LAB, DIV NUCL MAT TECHNOL, POB 1663, LOS ALAMOS, NM 87545 USA. NR 6 TC 0 Z9 0 U1 0 U2 0 PU AMER INST AERONAUT ASTRONAUT PI RESTON PA 1801 ALEXANDER BELL DRIVE, STE 500, RESTON, VA 22091 SN 0748-4658 J9 J PROPUL POWER JI J. Propul. Power PD MAY-JUN PY 1994 VL 10 IS 3 BP 425 EP 431 DI 10.2514/3.23752 PG 7 WC Engineering, Aerospace SC Engineering GA NM077 UT WOS:A1994NM07700019 ER PT J AU GRAUNDONS, JA DYER, FF AF GRAUNDONS, JA DYER, FF TI NEUTRON-ACTIVATION ANALYSIS OF LWR ION-EXCHANGE MIXED-BED RESINS FOR I-129 SO JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY-ARTICLES LA English DT Article; Proceedings Paper CT 2nd International Symposium on Nuclear Analytical Chemistry (NAC-II) CY JUN 03-05, 1992 CL UNIV TORONTO, TORONTO, CANADA HO UNIV TORONTO AB Iodine-129 was determined by neutron activation analysis (NAA) in mixed-bed ion exchange resins from four light water reactors (LWR), including two pressurized water reactors (PWR) and two boiling water reactors (BWR). Published procedures for NAA of I-129 in LWR resins were modified and adapted to the particular requirements of the Oak Ridge National Laboratory (ORNL) High Flux Isotope Reactor (HFIR) irradiation system. Observed I-129 concentrations, ranging from 1E-09 to 4E-07 muCi/g, were about 1000 times lower than the beta-gamma detection limits currently reported. RP GRAUNDONS, JA (reprint author), OAK RIDGE NATL LAB,MARTIN MARIETTA ENERGY SYST,POB 2008,OAK RIDGE,TN 37830, USA. NR 9 TC 2 Z9 2 U1 0 U2 0 PU AKADEMIAI KIADO PI BUDAPEST PA PO BOX 245, H-1519 BUDAPEST, HUNGARY SN 0236-5731 J9 J RADIOAN NUCL CH AR JI J. Radioanal. Nucl. Chem.-Artic. PD MAY PY 1994 VL 180 IS 1 BP 179 EP 185 DI 10.1007/BF02039917 PG 7 WC Chemistry, Analytical; Chemistry, Inorganic & Nuclear; Nuclear Science & Technology SC Chemistry; Nuclear Science & Technology GA NQ668 UT WOS:A1994NQ66800022 ER PT J AU DU, JY TAO, J KLEINHANS, FW MAZUR, P CRITSER, JK AF DU, JY TAO, J KLEINHANS, FW MAZUR, P CRITSER, JK TI WATER VOLUME AND OSMOTIC BEHAVIOR OF MOUSE SPERMATOZOA DETERMINED BY ELECTRON-PARAMAGNETIC-RESONANCE SO JOURNAL OF REPRODUCTION AND FERTILITY LA English DT Article ID SPIN-RESONANCE; SPERM; VISCOSITY; LABELS AB Experiments were conducted to determine the water volume and osmotic behaviour of mouse spermatozoa using an electron paramagnetic resonance technique using the spin label tempone, and the broadening agent potassium chromium oxalate. After a swim-up procedure, an average water volume of: 43.3 mu m(3) of individual spermatozoa was obtained at 290 mosmol. If a water compartment of 59% is assumed, the total volume of mouse spermatozoa is 73.4 mu m(3). A plot of the relative water volume of mouse spermatozoa versus the reciprocal of buffer osmolality (Boyle van't Hoff plot) is linear in the range 250-900 mosmol of sodium chloride solutions (r(2) = 0.96). The Boyle van't Hoff plot intercept indicates that 13% of the spin-label accessible isotonic water is osmotically inactive. C1 METHODIST HOSP INDIANA,CRYOBIOL RES INST,INDIANAPOLIS,IN 46202. INDIANA UNIV PURDUE UNIV,DEPT PHYS,INDIANAPOLIS,IN 46202. OAK RIDGE NATL LAB,DIV BIOL,OAK RIDGE,TN 37831. INDIANA UNIV,SCH MED,DEPT PHYSIOL & BIOPHYS & OBSTET GYNECOL,INDIANAPOLIS,IN 46202. PURDUE UNIV,SCH VET MED,DEPT VET CLIN SCI,W LAFAYETTE,IN 47907. FU NICHD NIH HHS [KO4-HD00980] NR 17 TC 32 Z9 33 U1 0 U2 1 PU J REPROD FERTIL INC PI CAMBRIDGE PA 22 NEWMARKET RD, CAMBRIDGE, ENGLAND CB5 8DT SN 0022-4251 J9 J REPROD FERTIL JI J. Reprod. Fertil. PD MAY PY 1994 VL 101 IS 1 BP 37 EP 42 PG 6 WC Reproductive Biology SC Reproductive Biology GA NR795 UT WOS:A1994NR79500007 PM 8064691 ER PT J AU GILES, DW DENN, MM AF GILES, DW DENN, MM TI THE EFFECT OF SUPPRESSION OF OFFGASSING ON THE RHEOMETRY OF THERMOTROPIC LIQUID-CRYSTALLINE POLYMERS SO JOURNAL OF RHEOLOGY LA English DT Article ID NORMAL-STRESS DIFFERENCE; RHEOLOGICAL PROPERTIES; CONCENTRATED-SOLUTIONS; AROMATIC COPOLYESTER; RODLIKE POLYMERS; TRANSIENT; BEHAVIOR; SHEAR; COPOLYMER; CAPILLARY AB Thermotropic liquid crystalline polymers commonly develop a bubble texture at time scales necessary to perform low-rate rheological experiments. We have fabricated a capillary rheometer capable of high-sensitivity (relatively low-rate) measurements under a hydrostatic pressure adequate to suppress formation of visible bubbles. Vectra A (a copolyester of 73% HBA and 27% HNA) exhibited a transient reduction in viscosity at low rates that is independent of strain history and dependent only on time in the melt; no change in inherent viscosity was observed despite a threefold change in viscosity. The transient, which was not observed at high rates on the time scale of the experiment, may reflect changes in the defect structure. The flow curve for a given thermal history (time in the melt) exhibited a flattening at low to intermediate rates, suggestive of the flow curves reported for lyotropic systems. This result is qualitatively in agreement with rotational rheometer measurements known to be contaminated by offgassing, which exhibit higher apparent viscosities but give the same flow curve shape. Rotational rheometer transients scaled with strain in a manner similar to that reported for lyotropic systems. Transient reduction in viscosity and flow curve flattening with decreasing rate was also observed in pressurized rheometer measurements of the fully nematic copolyester of 80% HBA and 20% PET; a decrease in inherent viscosity was observed for this polymer, but it appears to be too small to account for the observed decrease in viscosity with time. C1 UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. RP GILES, DW (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720, USA. NR 35 TC 21 Z9 21 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0148-6055 J9 J RHEOL JI J. Rheol. PD MAY-JUN PY 1994 VL 38 IS 3 BP 617 EP 637 DI 10.1122/1.550478 PG 21 WC Mechanics SC Mechanics GA NK495 UT WOS:A1994NK49500010 ER PT J AU AMEEL, TA WOOD, BD SIEBE, DA COLLIER, RK AF AMEEL, TA WOOD, BD SIEBE, DA COLLIER, RK TI PERFORMANCE PREDICTIONS OF SOLAR OPEN-CYCLE ABSORPTION AIR-CONDITIONING SYSTEMS IN 3 CLIMATIC REGIONS SO JOURNAL OF SOLAR ENERGY ENGINEERING-TRANSACTIONS OF THE ASME LA English DT Article AB Open-cycle absorption air conditioning is a promising type of solar-driven cooling system. It addresses, in a significant way, the problems of high solar collector costs and power requirements that are inherent in other solar cooling systems. Previous open-cycle absorption modeling studies have been very limited and included only the solar collection part of the system. The purpose of this study was to evaluate the potential for use of this type of system in various climatic regions of the United States. The study examines this promising type of air conditioning as a total system interacting dynamically with its environment. Mathematical analysis and computer simulation were used. System simulations were performed for three system design concepts. The Typical Meteorological Year data base for Miami, FL, Washington, D. C., and Phoenix, AZ, were used to estimate system potential. The best performance predictions resulted in approximately 60 percent of the seasonal load being met by an open-cycle absorption system in Miami, 70 percent in Washington, and 99 percent in Phoenix. C1 ARIZONA STATE UNIV,COLL ENGN & APPL SCI,CTR ENERGY SYST RES,TEMPE,AZ 85287. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. FLORIDA SOLAR ENERGY CTR,CAPE CANAVERAL,FL 32920. RP AMEEL, TA (reprint author), LOUISIANA TECH UNIV,DEPT MECH & IND ENGN,RUSTON,LA 71272, USA. NR 12 TC 4 Z9 4 U1 0 U2 0 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 SN 0199-6231 J9 J SOL ENERG-T ASME JI J. Sol. Energy Eng. Trans.-ASME PD MAY PY 1994 VL 116 IS 2 BP 107 EP 113 DI 10.1115/1.2930497 PG 7 WC Energy & Fuels; Engineering, Mechanical SC Energy & Fuels; Engineering GA NM847 UT WOS:A1994NM84700007 ER PT J AU SRIVASTAVA, RK LUUTHE, V MARRONE, BL HARRISHOOKER, S SRIDARAN, R AF SRIVASTAVA, RK LUUTHE, V MARRONE, BL HARRISHOOKER, S SRIDARAN, R TI INHIBITION OF STEROIDOGENESIS BY LUTEAL CELLS OF EARLY-PREGNANCY IN THE RAT IN RESPONSE TO IN-VITRO ADMINISTRATION OF A GONADOTROPIN-RELEASING-HORMONE AGONIST SO JOURNAL OF STEROID BIOCHEMISTRY AND MOLECULAR BIOLOGY LA English DT Article ID LUTEINIZING-HORMONE; GRANULOSA-CELLS; PROGESTERONE PRODUCTION; ESTRADIOL RECEPTORS; OVARY; PITUITARY; GNRH; LH; EXPRESSION; SECRETION AB Previous studies from this laboratory have demonstrated that the administration of a gonadotropin-releasing hormone agonist (GnRH-Ag) in vivo in early or mid-pregnancy to rats induces antifertility effects by suppressing the luteal production of progesterone (P-4) within 24 h with a concomitant increase in luteal lipid droplets and decreases in the luteal cytochrome P450 side chain cleavage (P450scc) enzyme and its mRNA content. These observations suggest a direct inhibitory effect of GnRH-Ag on the corpus luteum. Here we demonstrate a suppressive effect of GnRH-Ag in vitro on the basal P-4, pregnenolone (P-5) and 20 alpha-dihydroprogesterone (20 alpha-DHP) production by luteal cells obtained during early pregnancy in rats. We further studied its effect on two key enzymes, namely P450scc and 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), which participate in the conversion of cholesterol to P-5 and conversion of P-5 to P-4, respectively. We observed that two doses of GnRH-Ag, 10(-4) and 10(-7) M, suppress the basal P-4 production in vitro after 12 h of incubation by luteal cells; P-4 remained suppressed after 48 h of incubation. Basal P-5 production was also suppressed after luteal cells were incubated for 12 h with 10(-4) and 10(-7) M GnRH-Ag, but incubation for 48 h with GnRH-Ag failed to alter P-5 production by these cells. 20 alpha-DHP production was suppressed after incubating the luteal cells with both doses of GnRH-Ag for 12 h. GnRH-Ag inhibited P450scc activity after 12 h of incubation and 3 beta-HSD protein content at all time periods measured. These results suggest that GnRH exerts a direct inhibitory effect on luteal steroidogenesis. This inhibition is due to its suppressive effect on P450scc and/or 3 beta-HSD and not due to an increase in P-4 metabolites. C1 MOREHOUSE SCH MED,DEPT PHYSIOL,ATLANTA,GA 30310. MOREHOUSE SCH MED,DEPT PATHOL & MED,ATLANTA,GA 30310. CHU LAVAL,RES CTR,DEPT MOLEC ENDOCRINOL,QUEBEC CITY G1V 4G2,PQ,CANADA. LOS ALAMOS NATL LAB,DIV LIFE SCI,LOS ALAMOS,NM 87545. FU NICHD NIH HHS [HD 17867] NR 36 TC 8 Z9 8 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0960-0760 J9 J STEROID BIOCHEM JI J. Steroid Biochem. Mol. Biol. PD MAY PY 1994 VL 49 IS 1 BP 73 EP 79 DI 10.1016/0960-0760(94)90303-4 PG 7 WC Biochemistry & Molecular Biology; Endocrinology & Metabolism SC Biochemistry & Molecular Biology; Endocrinology & Metabolism GA NR137 UT WOS:A1994NR13700010 PM 8003442 ER PT J AU BROSHA, EL GARZON, FH RAISTRICK, ID DAVIES, PK AF BROSHA, EL GARZON, FH RAISTRICK, ID DAVIES, PK TI LOW-TEMPERATURE SYNTHESIS AND PHASE-EQUILIBRIA IN THE Y-CU-O BINARY-SYSTEM SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID THERMODYNAMIC STABILITY; Y2O3-BAO-CUO SYSTEM; CRYSTAL-CHEMISTRY; DIFFRACTION DATA; Y2CU2O5; COMPATIBILITIES; THERMOCHEMISTRY; 950-DEGREES-C; DIAGRAMS; OXIDES AB The low-temperature phase relations in the Y-Cu-0 system were examined using ultrasonically prepared, freeze-dried nitrate precursors. Under 1 atm of oxygen, Y2Cu2O5 was found to be stable above 955 +/- 5 K; below this temperature, the component binary oxides CuO and Y2O3 are the only stable phases in the system. The entropy of formation of Y2Cu2O5, with respect to the component oxides, was calculated to be 5.3 +/- 2.3 J/(mol.K) at 955 K. Bond valence analyses indicate that the entropy stabilization of this compound is most likely caused by the underbonded character of the copper ions. C1 UNIV PENN,DEPT MAT SCI & ENGN,PHILADELPHIA,PA 19104. RP BROSHA, EL (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 31 TC 4 Z9 4 U1 1 U2 3 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 1994 VL 77 IS 5 BP 1139 EP 1142 DI 10.1111/j.1151-2916.1994.tb05385.x PG 4 WC Materials Science, Ceramics SC Materials Science GA NM655 UT WOS:A1994NM65500002 ER PT J AU CHIANG, YM SILVERMAN, LA FRENCH, RH CANNON, RM AF CHIANG, YM SILVERMAN, LA FRENCH, RH CANNON, RM TI THIN GLASS-FILM BETWEEN ULTRAFINE CONDUCTOR PARTICLES IN THICK-FILM RESISTORS SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID RAY ABSORPTION-SPECTROSCOPY; EQUILIBRIUM THICKNESS; CERAMIC MATERIALS; SEGREGATION; MODEL AB Thick-film resistors are electrical composites containing ultrafine particles of ruthenate conductor (Pb2RU2O7 in the present materials) distributed in a highly modified silicate glass. We show that conductor particles remain flocced in the absence of any applied or capillary pressures, but are separated at equilibrium by a nanometer-thick film of glass. Microstructures show evidence for liquid-phase sintering, i.e., contact flattening of particles, under van der Waals attraction alone. Titania addition, which in dilute concentrations markedly increases the resistivity, decreases the temperature coefficient of resistance, and improves voltage stability and noise, is found to increase the equilibrium film thickness between particles by a few angstroms. STEM analyses show that the added titania preferentially concentrates in the silicate-rich grain boundary film, as well as at particle-glass interfaces. The roles of interparticle forces and adsorption on the glass film thickness with and without titania are discussed. The large increase in resistivity caused by titania additions is attributed to the increase in film thickness as well as to local chemical changes of two possible types. Titania enrichment within the glass film itself is expected to decrease the local ruthenium ion solubility, and this along with the possible formation of a more insulating titania-substituted surface layer on ruthenate grains will decrease the tunneling conductivity between conductor grains. C1 DUPONT CO INC,CENT RES & DEV,WILMINGTON,DE 19880. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP CHIANG, YM (reprint author), MIT,DEPT MAT SCI & ENGN,CAMBRIDGE,MA 02139, USA. RI French, Roger/E-1986-2011 OI French, Roger/0000-0002-6162-0532 NR 30 TC 117 Z9 118 U1 0 U2 18 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 1994 VL 77 IS 5 BP 1143 EP 1152 DI 10.1111/j.1151-2916.1994.tb05386.x PG 10 WC Materials Science, Ceramics SC Materials Science GA NM655 UT WOS:A1994NM65500003 ER PT J AU MENON, MN FANG, HT WU, DC JENKINS, MG FERBER, MK MORE, KL HUBBARD, CR NOLAN, TA AF MENON, MN FANG, HT WU, DC JENKINS, MG FERBER, MK MORE, KL HUBBARD, CR NOLAN, TA TI CREEP AND STRESS RUPTURE BEHAVIOR OF AN ADVANCED SILICON-NITRIDE .1. EXPERIMENTAL-OBSERVATIONS SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID HOT-PRESSED SI3N4; HIGH-TEMPERATURE STRENGTH; PHASE AB Cylindrical buttonhead specimens of an advanced silicon nitride were tested in uniaxial tension at temperatures between 1422 and 1673 K. In the range 1477 to 1673 K, creep deformation was reliably measured using high-temperature contact probe extensometry. Extensive scanning and transmission electron microscopy has revealed the formation of lenticular cavities at two-grain junctions at all temperatures (1422-1673 K) and extensive triple-junction cavitation occurring at the higher temperatures (1644-1673 K). Cavitation is believed to be part of the net creep process. The stress rupture data show stratification of the Monkman-Grant lines with respect to temperature. Failure strain increased with increase in rupture time or temperature, or decrease in stress. Fractography showed that final failure occurred by subcritical crack growth in all specimens. C1 UNIV WASHINGTON,DEPT MECH ENGN,SEATTLE,WA 98195. OAK RIDGE NATL LAB,HIGH TEMP MAT LAB,OAK RIDGE,TN 37831. RP MENON, MN (reprint author), ALLIEDSIGNAL AEROSP CO,ALLIEDSIGNAL ENGINES,PHOENIX,AZ 85072, USA. RI More, Karren/A-8097-2016 OI More, Karren/0000-0001-5223-9097 NR 19 TC 69 Z9 71 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 1994 VL 77 IS 5 BP 1217 EP 1227 DI 10.1111/j.1151-2916.1994.tb05395.x PG 11 WC Materials Science, Ceramics SC Materials Science GA NM655 UT WOS:A1994NM65500012 ER PT J AU MENON, MN FANG, HT WU, DC JENKINS, MG FERBER, MK AF MENON, MN FANG, HT WU, DC JENKINS, MG FERBER, MK TI CREEP AND STRESS RUPTURE BEHAVIOR OF AN ADVANCED SILICON-NITRIDE .2. CREEP RATE BEHAVIOR SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID GLASS; OXIDATION; STRENGTH; CERAMICS; PHASE; Y2O3 AB In Part I of this paper, experimental observations on creep testing of 74 tensile specimens of an advanced silicon nitride were presented. In this part, equations are developed for predicting creep rates in the primary and secondary regimes in the temperature range 1477-1673 K. The resulting model predicts creep strain rates to within a factor of two. The underlying phenomenological basis, which employs an activation energy approach, is discussed. The mechanisms that are likely to be responsible for the transiency of the primary creep regime and for the unique stress and temperature dependencies of the creep rates are explored. C1 UNIV WASHINGTON,DEPT MECH ENGN,SEATTLE,WA 98195. OAK RIDGE NATL LAB,HIGH TEMP MAT LAB,OAK RIDGE,TN 37831. RP MENON, MN (reprint author), ALLIEDSIGNAL AEROSP CO,ALLIEDSIGNAL ENGINES,PHOENIX,AZ 85072, USA. NR 28 TC 30 Z9 30 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 1994 VL 77 IS 5 BP 1228 EP 1234 DI 10.1111/j.1151-2916.1994.tb05396.x PG 7 WC Materials Science, Ceramics SC Materials Science GA NM655 UT WOS:A1994NM65500013 ER PT J AU MENON, MN FANG, HT WU, DC JENKINS, MG FERBER, MK AF MENON, MN FANG, HT WU, DC JENKINS, MG FERBER, MK TI CREEP AND STRESS RUPTURE BEHAVIOR OF AN ADVANCED SILICON-NITRIDE .3. STRESS RUPTURE AND THE MONKMAN-GRANT RELATIONSHIP SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID HIGH-TEMPERATURE FAILURE; CRACK-GROWTH; LIQUID-PHASE; STRENGTH; CERAMICS AB The applicability of the Monkman-Grant relationship to predict the stress rupture life of NT154 silicon nitride is examined. The data show that the Monkman-Grant lines relating rupture life to minimum creep rate are stratified with respect to temperature. A modification to the current expression for the Monkman-Grant relation is proposed to accommodate this temperature dependence. A phenomenological approach based on crack growth as the failure mechanism is presented to explain this temperature dependence. The results can be interpreted as suggesting that the stress dependence of the failure process is greater than that for creep. C1 UNIV WASHINGTON,DEPT MECH ENGN,SEATTLE,WA 98195. OAK RIDGE NATL LAB,HIGH TEMP MAT LAB,OAK RIDGE,TN 37831. RP MENON, MN (reprint author), ALLIEDSIGNAL AEROSP CO,ALLIEDSIGNAL ENGINES,PHOENIX,AZ 85072, USA. NR 27 TC 23 Z9 23 U1 0 U2 0 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD MAY PY 1994 VL 77 IS 5 BP 1235 EP 1241 DI 10.1111/j.1151-2916.1994.tb05397.x PG 7 WC Materials Science, Ceramics SC Materials Science GA NM655 UT WOS:A1994NM65500014 ER PT J AU EGAN, EW TOBIAS, CW AF EGAN, EW TOBIAS, CW TI MEASUREMENT OF INTERFACIAL RE-EQUILIBRATION DURING HYDROGEN BUBBLE COALESCENCE SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID DOUBLE-LAYER FORCES; LONDON-VANDERWAALS; FLUID INTERFACE; LIQUID-FILMS; SMALL DROP; RUPTURE; STABILITY; PLANE AB A new experimental technique has been developed and tested to measure the interfacial velocities associated with the coalescence of small, electrolytically generated gas bubbles. The technique involves measuring, by means of a linear photodiode array, the rate of deflection of a laser-light sheet caused by the movement of a newly formed boundary between coalescing bubbles. Bubble pairs in the 500 to 1000 mum range were generated at precisely controlled rates between two parallel glass-encased microelectrodes. Correlation of data obtained on the coalescence of two hydrogen bubbles of identical size shows that the position of the interface along the coalescence plane varies with the square-root of time, in agreement with the hole expansion model advanced by Charles and Mason.2 Initial interfacial velocities are in the range of 200 to 300 cm/s. Larger numbers of such events occurring simultaneously at gas evolving electrodes will significantly disturb the fluid immediately adjacent to the electrode, thereby improving mass transport rates to and from the surface. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM ENGN,BERKELEY,CA 94720. NR 20 TC 13 Z9 13 U1 0 U2 2 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1994 VL 141 IS 5 BP 1118 EP 1126 DI 10.1149/1.2054883 PG 9 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA NJ886 UT WOS:A1994NJ88600009 ER PT J AU MAO, D KIM, KJ FRANK, AJ AF MAO, D KIM, KJ FRANK, AJ TI OPEN-CIRCUIT PHOTOVOLTAGE AND CHARGE RECOMBINATION AT SEMICONDUCTOR LIQUID INTERFACES SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID SURFACE RECOMBINATION; CHEMICAL MODIFICATION; CARRIER TRANSPORT; SOLAR-CELL; ELECTRODES; JUNCTIONS; VOLTAGE; PHOTOCURRENT; ELECTROLYTES; PHOTOANODES AB A simple, quantitative relationship between the semiconductor surface recombination velocity (S(r)) and the open-circuit photovoltage (V(oc)) of photoelectrochemical systems was derived and verified experimentally. Experimental results obtained for the n-Si/acetone-FeCp2+/0-LiClO4 junction indicate that V(oc) is controlled by surface recombination. Quantitative analysis of the results using the derived expression yields values of the barrier height and S(r) that compare favorably with published data. Application of the equation to other semiconductor/liquid junction cells suggests that the expression may be important in evaluating and understanding the behavior of a wide range of photoelectrochemical systems. RP MAO, D (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 34 TC 12 Z9 12 U1 0 U2 8 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1994 VL 141 IS 5 BP 1231 EP 1236 DI 10.1149/1.2054901 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA NJ886 UT WOS:A1994NJ88600027 ER PT J AU VITUS, CM DAVENPORT, AJ AF VITUS, CM DAVENPORT, AJ TI IN-SITU SCANNING-TUNNELING-MICROSCOPY STUDIES OF THE FORMATION AND REDUCTION OF A GOLD OXIDE MONOLAYER ON AU(111) SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID SINGLE-CRYSTAL PLANES; ELECTROCHEMICAL OXIDATION; ELECTRODE SURFACES; AQUEOUS-SOLUTIONS; ELEMENTARY STEPS; RECONSTRUCTION; AU(100); ACID; AU; INTERFACES AB An in situ scanning tunneling microscopy study of morphological changes during formation and reduction of an oxide monolayer on Au(111) in 0.1M HClO4 is presented. During oxidation of a freshly prepared surface, the (1 x 1) arrangement of metal atoms persisted through the hydroxide peak at 1.35 V vs. reversible hydrogen electrode (RHE). At the peak potential for AuO formation (1.55 V vs. RHE), a slightly roughened layer propagated across terraces starting from edges. An ordered oxidized surface structure was not resolved and the surface roughness is approximately 0.08 +/- 0.02 nm. This is ascribed tentatively to the formation of a monolayer of oxide by place exchange. During a slow cathodic sweep, the oxidized surface restructured into wormlike islands of monatomic height at the peak potential for oxide reduction at 1.15 V vs. RHE. These islands coalesced to form flat terraces with monatomic pits in the surface at potentials within the double-layer region. Pits eventually fused with terrace ledges to restore the original terrace morphology. RP VITUS, CM (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,DIV MAT SCI,UPTON,NY 11973, USA. RI Davenport, Alison/J-6089-2013 OI Davenport, Alison/0000-0003-0853-515X NR 34 TC 59 Z9 59 U1 1 U2 17 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD MAY PY 1994 VL 141 IS 5 BP 1291 EP 1298 DI 10.1149/1.2054912 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA NJ886 UT WOS:A1994NJ88600038 ER PT J AU MARSHALL, CD PAYNE, SA HENESIAN, MA SPETH, JA POWELL, HT AF MARSHALL, CD PAYNE, SA HENESIAN, MA SPETH, JA POWELL, HT TI ULTRAVIOLET-INDUCED TRANSIENT ABSORPTION IN POTASSIUM DIHYDROGEN PHOSPHATE AND ITS INFLUENCE ON FREQUENCY-CONVERSION SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID HARMONIC-GENERATION; 2-PHOTON ABSORPTION; RADIATION-DAMAGE; 266 NM; ADP; KDP; CRYSTALS; KDSTARP; DEFECTS; KH2PO4 AB The optical properties of an ultraviolet (266-nm) -induced transient absorption in normal and deuterated potassium dihydrogen phosphate crystals are discussed. Our main contribution has been to analyze this effect quantitatively, assess its effect on ultraviolet (UV) frequency-conversion applications, and examine sample variability. As observed previously [Chem. Phys. Lett. 207, 540 (1993)], the transient absorption is broad (approximately 200-700 nm) and is suggested to arise from an induced defect state resulting from the promotion of an electron into the conduction band by two-photon absorption. At room temperature we find that the defect absorption decays over a wide variety of time scales, ranging from fractions of a second to several days, depending on the particular sample under study. The decay time does not appear to be correlated with deuteration or chemical impurities. The temperature-dependent decay rate has an Arrhenius behavior with a single activation energy of 0.51 +/- 0.04 eV for all samples studied, and the decay rate appears to be mediated by a diffusional process as previously postulated. We determined the defect absorption cross section at its spectral peak to be 6 +/- 3 x 10(-18) cm2. Based on these and other measurements, we have numerically modeled previously published experimental data on fourth-harmonic frequency conversion of a Nd:YLF laser and found good agreement when the effects of transient absorption are included. RP MARSHALL, CD (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,LIVERMORE,CA 94551, USA. NR 44 TC 60 Z9 67 U1 1 U2 8 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 1994 VL 11 IS 5 BP 774 EP 785 DI 10.1364/JOSAB.11.000774 PG 12 WC Optics SC Optics GA NL959 UT WOS:A1994NL95900011 ER PT J AU UEDA, T KATH, WL AF UEDA, T KATH, WL TI STOCHASTIC SIMULATION OF PULSES IN NONLINEAR-OPTICAL FIBERS WITH RANDOM BIREFRINGENCE SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS LA English DT Article ID COMMUNICATION-SYSTEMS; BANDWIDTH LIMITS; SOLITONS; POLARIZATION; PROPAGATION; DYNAMICS; STABILITY; AMPLITUDES AB Numerical simulations of nonlinear pulse propagation in optical fibers with randomly varying birefringence are presented. For short-length-scale randomness the dominant effect is due to phase-velocity birefringence and produces a probabilistic uncertainty that increases with propagation distance for the expected value of the pulse's polarization state. An approximate evolution equation for the probability distribution of the polarization state was derived previously [Physica D 55, 166 (1992)]. Comparisons between this distribution and Monte Carlo simulations are presented that demonstrate the validity of the analytical results. The simulations also show that the polarization state of a pulse is completely randomized on the longer soliton-period length scale. This provides justification for the assumption of a uniformly distributed polarization state used in previous analyses of this problem [Opt. Lett. 16, 1231 (1991); J. Lightwave Technol. 10, 28 (1992)]. Furthermore, the higher-order effects of group birefringence are assessed. In particular, the polarizationstate fluctuations induced by the randomness are shown to reduce significantly the effects of pulse splitting and dispersive radiation loss caused by group-velocity birefringence. C1 LOS ALAMOS NATL LAB,COMP RES GRP C3,LOS ALAMOS,NM 87545. NORTHWESTERN UNIV,MCCORMICK SCH ENGN & APPL SCI,EVANSTON,IL 60208. RI Kath, William/B-6771-2009 NR 22 TC 14 Z9 14 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 SN 0740-3224 J9 J OPT SOC AM B JI J. Opt. Soc. Am. B-Opt. Phys. PD MAY PY 1994 VL 11 IS 5 BP 818 EP 825 DI 10.1364/JOSAB.11.000818 PG 8 WC Optics SC Optics GA NL959 UT WOS:A1994NL95900017 ER PT J AU SIMONS, JK FRIGO, SP TAYLOR, JW ROSENBERG, RA AF SIMONS, JK FRIGO, SP TAYLOR, JW ROSENBERG, RA TI SYNCHROTRON-RADIATION (5-50 EV) INDUCED DEGRADATION OF FLUORINATED POLYMERS SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID ELECTRON-STIMULATED DESORPTION; POLY(TETRAFLUOROETHYLENE); POLYTETRAFLUOROETHYLENE; IRRADIATION AB The photochemistry of solid, free-standing films of poly(tetrafluoroethylene) (PTFE) and poly(hexafluoropropylene-tetrafluoroethylene) (FEP) was investigated by monitoring the neutral photodesorption products produced upon irradiation with synchrotron radiation (5-50 eV). CF3, C2F5, C3F5, C3F7, and C4F7 were the predominant species observed in the mass spectra of the irradiated polymers. Oligomers at least as large as 293 amu (C7F12) were also detected. Distinct differences are observed in the photodesorption yields and time responses of the yields based on the energy of the initial excitation. An edge jump at 22 eV in the photon-stimulated desorption spectra of both PTFE and FEP films is assigned to the ionization of the C(2s) states of the polymers. The energy dependence of the photodesorption yields is accounted for by considering two separate reaction pathways. C1 UNIV WISCONSIN,DEPT PHYS,STOUGHTON,WI 53589. UNIV WISCONSIN,DEPT CHEM,MADISON,WI 53706. ARGONNE NATL LAB,ARGONNE,IL 60439. RP SIMONS, JK (reprint author), UNIV WISCONSIN,CTR SYNCHROTRON RADIAT,STOUGHTON,WI 53589, USA. RI Rosenberg, Richard/K-3442-2012 NR 24 TC 24 Z9 24 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1994 VL 12 IS 3 BP 681 EP 689 DI 10.1116/1.578853 PG 9 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NL925 UT WOS:A1994NL92500010 ER PT J AU MAYA, L AF MAYA, L TI DEPOSITION OF AMORPHOUS HYDROGENATED SILICON-CARBIDE FILMS USING ORGANOSILANES IN AN ARGON HYDROGEN PLASMA SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID CHEMICAL VAPOR-DEPOSITION; OPTICAL-PROPERTIES; SIC-H; GLOW-DISCHARGE; SOLAR-CELL; THIN-FILMS; ALLOYS; FREQUENCIES; MICROWAVE; NITRIDE AB Nearly stoichiometric, amorphous silicon carbide films with a relatively low hydrogen content were deposited from organsilanes on a variety of substrates in a microwave-generated plasma without external heating. The films undergo little weight loss upon pyrolysis to 800-degrees-C. The effect of the different deposition parameters on the film composition and the exhaust gas was established through a battery of tests including infrared Fourier transform spectroscopy, Auger electron spectroscopy, x-ray photoelectron spectroscopy, ellipsometry, and mass spectroscopy. For a given power level there is a limiting feeding rate of the precursor under which operation of the system is dominated by thermodynamics and thus leads to the desired product. Beyond that limit, excessive hydrogen incorporation and carbosilane polymer formation takes place. The hydrogen content of the plasma is also an important parameter affecting the chemistry of the deposition. In the thermodynamically dominated regime the nature of the precursor has no effect on the quality of the film. It affects only the relative utilization efficiency. RP MAYA, L (reprint author), OAK RIDGE NATL LAB,DIV CHEM,POB 20086119,OAK RIDGE,TN 37831, USA. NR 32 TC 10 Z9 10 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1994 VL 12 IS 3 BP 754 EP 759 DI 10.1116/1.578819 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NL925 UT WOS:A1994NL92500022 ER PT J AU NIEMCZYK, TM WANGMANEERAT, B HAALAND, DM AF NIEMCZYK, TM WANGMANEERAT, B HAALAND, DM TI PRECISE PROPERTY DETERMINATIONS OF ARSENOSILICATE GLASS THIN-FILMS USING INFRARED-SPECTROSCOPY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article ID PHOSPHOSILICATE GLASS; SPECTRAL DATA; SILICON; CALIBRATION; DEPOSITION AB The combination of infrared spectroscopy and chemometric data analysis has been shown to provide a valuable method for rapid, nondestructive, at-line characterization of film properties for a variety of thin films. We demonstrate the precise determination of As content and film thickness for arsenosilicate glass thin films. Calibrations based on the infrared data yielded standard errors of prediction of 0.10 wt. % and 10 angstrom for the arsenic content and film thickness, respectively. Further, it is demonstrated that profiling the film properties across the wafer surface can increase the accuracy of the determinations by improving the correspondence of the infrared and reference property measurements. This profiling also provides rapid information about spatial variations of film properties. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RP NIEMCZYK, TM (reprint author), UNIV NEW MEXICO,DEPT CHEM,ALBUQUERQUE,NM 87131, USA. NR 22 TC 1 Z9 1 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1994 VL 12 IS 3 BP 835 EP 838 DI 10.1116/1.578832 PG 4 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NL925 UT WOS:A1994NL92500035 ER PT J AU WELCH, KM PATE, DJ TODD, RJ AF WELCH, KM PATE, DJ TODD, RJ TI PUMPING OF HELIUM AND HYDROGEN BY SPUTTER-ION PUMPS .2. HYDROGEN PUMPING SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A-VACUUM SURFACES AND FILMS LA English DT Article AB The pumping of helium by various forms of sputter-ion pumps (i.e., SIPs) is given in part I [K. M. Welch, D. J. Pate, and R. J. Todd, J. Vac. Sci. Technol. A 11, 1607 (1993)]. The pumping of hydrogen in diode and triode SIPs is herein discussed. The type of cathode material used in these pumps is shown to have a significant impact on the effectiveness with which hydrogen is pumped. Examples of this include data for pumps with aluminum, titanium, and titanium-alloy cathodes. Diode pumps with aluminum cathodes are shown to be no more effective in the pumping of hydrogen than in the pumping of helium. The use of titanium anodes and titanium shielding of a pump body is also shown to impact measurably the speed of a pump at very low pressures. This stems from the fact that hydrogen is X 10(6) more soluble in titanium than in stainless steel. Hydrogen becomes resident in the anodes because of fast neutral burial. Ions and fast neutrals of hydrogen are also buried in the walls of pump bodies. Outgassing of this hydrogen from the anodes and pump bodies results in a gradual increase in pump base pressure and consequential decrease in hydrogen pump speed at very low base pressures. RP WELCH, KM (reprint author), BROOKHAVEN NATL LAB,RELATIV HEAVY ION COLLIDER PROJECT,UPTON,NY 11973, USA. NR 22 TC 2 Z9 2 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0734-2101 J9 J VAC SCI TECHNOL A JI J. Vac. Sci. Technol. A-Vac. Surf. Films PD MAY-JUN PY 1994 VL 12 IS 3 BP 861 EP 866 DI 10.1116/1.579267 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NL925 UT WOS:A1994NL92500039 ER PT J AU SHIEH, SY EVANS, JW AF SHIEH, SY EVANS, JW TI SOME PRELIMINARY-OBSERVATIONS OF THE RAPID THERMAL-OXIDATION OF POROUS SILICON, AND THE RAPID THERMAL NITRIDING OF OXIDIZED POROUS SILICON SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Note ID GATE DIELECTRICS; FILMS; NITRIDATION; OXIDE; TEMPERATURE; DEPOSITION; OXYNITRIDE; SIO2 AB Porous silicon, produced by the anodic oxidation of p-type single crystal wafers of silicon in hydrofluoric acid/ethanol electrolytes has been subjected to rapid thermal oxidation. For comparison purposes, and also to generate porous oxide for subsequent nitriding, other samples of porous silicon were subjected to conventional furnace oxidation. By TEM, EDS, and ESCA it was shown that the structures and compositions of the oxides produced by the two routes were similar. It was further demonstrated that oxidized porous silicon could be nitrided by rapid thermal processing. The resulting structure, although still porous, showed a much diminished etching rate in hydrofluoric acid, compared to the original oxide. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP EVANS, JW (reprint author), UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720, USA. NR 22 TC 2 Z9 2 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1994 VL 12 IS 3 BP 1422 EP 1426 DI 10.1116/1.587312 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA NR918 UT WOS:A1994NR91800019 ER PT J AU DUNPHY, JC CHAPELIER, C OGLETREE, DF SALMERON, MB AF DUNPHY, JC CHAPELIER, C OGLETREE, DF SALMERON, MB TI DEPOSITION OF AU ON A SULFUR COVERED MO(100) SURFACE - ADSORBATE ADSORBATE INTERACTION AND GROWTH SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 1993 International Conference on Scanning Tunneling Microscopy (STM 93) CY AUG 09-13, 1993 CL BEIJING, PEOPLES R CHINA SP CHINESE ACAD SCI, INST CHEM, STATE SCI & TECHNOL COMMISS, CHINA ASSOC SCI & TECHNOL, NATL NAT SCI FDN CHINA, MINIST PERSONNEL BEIJING, STATE EDUC COMMISS, AMER VACUUM SOC, AVS NANOMETER SCALE SCI & TECHNOL DIV, SONY CORP RES CTR, ULVAC CORP, NIPPON STEEL, TOSHIBA R&D CTR, MATSUSHITA ELECT IND CO, SURFACE SCI RES FDN ID SCANNING-TUNNELING-MICROSCOPY; SINGLE-CRYSTAL SURFACES; OVERLAYERS; OXYGEN; SCIENCE; FILMS; STM; CO AB Gold was deposited on a clean and on a sulfided Mo(001) surface to study the initial stages of growth and the influence of chemisorbed layers. On the clean surface, Au forms a c(2 X 2) structure at low coverages. At coverages above half of a monolayer more complicated structures are revealed by low energy electron diffraction and scanning tunneling microscopy. On the sulfided surface, Au was found to bind directly to the metal by displacing the S to a higher coverage structure. At sulfur saturation Au forms three-dimensional clusters separated by areas covered by sulfur in the highest coverage structure. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. RP DUNPHY, JC (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720, USA. RI Ogletree, D Frank/D-9833-2016 OI Ogletree, D Frank/0000-0002-8159-0182 NR 14 TC 18 Z9 18 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1994 VL 12 IS 3 BP 1742 EP 1746 DI 10.1116/1.587589 PG 5 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA NR918 UT WOS:A1994NR91800092 ER PT J AU MCINTYRE, BJ SAUTET, P DUNPHY, JC SALMERON, M SOMORJAI, GA AF MCINTYRE, BJ SAUTET, P DUNPHY, JC SALMERON, M SOMORJAI, GA TI SCANNING-TUNNELING-MICROSCOPY TIP-DEPENDENT IMAGE-CONTRAST OF S PT(111) BY CONTROLLED ATOM-TRANSFER SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 1993 International Conference on Scanning Tunneling Microscopy (STM 93) CY AUG 09-13, 1993 CL BEIJING, PEOPLES R CHINA SP CHINESE ACAD SCI, INST CHEM, STATE SCI & TECHNOL COMMISS, CHINA ASSOC SCI & TECHNOL, NATL NAT SCI FDN CHINA, MINIST PERSONNEL BEIJING, STATE EDUC COMMISS, AMER VACUUM SOC, AVS NANOMETER SCALE SCI & TECHNOL DIV, SONY CORP RES CTR, ULVAC CORP, NIPPON STEEL, TOSHIBA R&D CTR, MATSUSHITA ELECT IND CO, SURFACE SCI RES FDN ID STM AB Sudden changes in the detailed appearance and corrugation of atomic-resolution scanning tunneling microscopy (STM) images are commonly observed. In particular, these effects for the Pt(111)(square-root 3 X square-root 3)R30-degrees-sulfur structure have been studied. Corrugation changes have been investigated by the controlled transfer of atoms between tip and sample. Theoretical image simulations using electron scattering quantum chemical methods show that the, image contrast is strongly dependent on the chemical identity of the STM tip atom. Observed changes in the sulfur images can be explained by changes from platinum-terminated to sulfur-terminated STM tips. RP MCINTYRE, BJ (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720, USA. RI Sautet, Philippe/G-3710-2014 OI Sautet, Philippe/0000-0002-8444-3348 NR 5 TC 23 Z9 23 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1994 VL 12 IS 3 BP 1751 EP 1753 DI 10.1116/1.587591 PG 3 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA NR918 UT WOS:A1994NR91800094 ER PT J AU ZHENG, JF LIU, X WEBER, ER OGLETREE, DF SALMERON AF ZHENG, JF LIU, X WEBER, ER OGLETREE, DF SALMERON TI SI DONORS (SI(GA)) IN GAAS OBSERVED BY SCANNING-TUNNELING-MICROSCOPY SO JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B LA English DT Article; Proceedings Paper CT 1993 International Conference on Scanning Tunneling Microscopy (STM 93) CY AUG 09-13, 1993 CL BEIJING, PEOPLES R CHINA SP CHINESE ACAD SCI, INST CHEM, STATE SCI & TECHNOL COMMISS, CHINA ASSOC SCI & TECHNOL, NATL NAT SCI FDN CHINA, MINIST PERSONNEL BEIJING, STATE EDUC COMMISS, AMER VACUUM SOC, AVS NANOMETER SCALE SCI & TECHNOL DIV, SONY CORP RES CTR, ULVAC CORP, NIPPON STEEL, TOSHIBA R&D CTR, MATSUSHITA ELECT IND CO, SURFACE SCI RES FDN ID GAAS(110) SURFACE; SPECTROSCOPY AB We report the direct observation of Si(Ga) donors in the top six layers of GaAs(110). Surface Si(Ga) has a localized electronic feature due to its dangling bond, while subsurface Si(Ga) produces delocalized protrusions in filled and empty state scanning tunneling microscopy images, with a full width at half-maximum of approximately 25 angstrom and a height from approximately 0.2 to 2 angstrom, depending on the sample bias and location under the surface. The delocalized features of subsurface Si(Ga) can be understood in terms of the perturbation of the local band structure by the Coulomb potential of Si(Ga). C1 LAWRENCE BERKELEY LAB,DEPT MAT SCI,BERKELEY,CA 94720. RP ZHENG, JF (reprint author), UNIV CALIF BERKELEY,DEPT MAT SCI,BERKELEY,CA 94720, USA. RI Ogletree, D Frank/D-9833-2016 OI Ogletree, D Frank/0000-0002-8159-0182 NR 14 TC 12 Z9 12 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1071-1023 J9 J VAC SCI TECHNOL B JI J. Vac. Sci. Technol. B PD MAY-JUN PY 1994 VL 12 IS 3 BP 2104 EP 2106 DI 10.1116/1.587716 PG 3 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Physics, Applied SC Engineering; Science & Technology - Other Topics; Physics GA NR918 UT WOS:A1994NR91800180 ER PT J AU WHITE, TD ANDERSON, RA AF WHITE, TD ANDERSON, RA TI LOCOMOTOR PATTERNS AND COSTS AS RELATED TO BODY-SIZE AND FORM IN TEIID LIZARDS SO JOURNAL OF ZOOLOGY LA English DT Article ID TERRESTRIAL LOCOMOTION; STRIDE FREQUENCY; LIMB BONES; ENERGY-EXPENDITURE; MAMMALS; SPEED; GAIT; ENERGETICS; MECHANICS; BIRDS AB Stride parameters and gaits were examined in seven species of teiid lizards in an attempt to understand size-dependent variation of locomotor patterns. Scaling of body dimensions to body mass revealed that axial measures conformed to geometric similarity, whereas the limb segments exhibited an allometry which was statistically significantly less than geometric similarity. Variations in the relationships between stride lengths, stride frequencies and duty factors (% of the stride that foot contacts ground) represented locomotor specializations and were not strictly size-dependent among species. At body length equivalent velocities, stride length and stride frequency scaled to body mass(0.40+/-0.06 and 0.09+/-0.03), respectively. Cost during locomotion at body length equivalent velocities could be estimated by the square of the product of stride length and stride frequency. Plotting the cost during locomotion for geometrically similar lizards against body mass yielded an estimate of the cost during locomotion that was proportional to mass(0.62+/-0.11). An estimate of the mass-specific cost during locomotion at body length-equivalent velocities scales to mass(-0.38+/-0.11). Because the limbs of these lizards exhibit an allometry less than geometric similarity, a correction of the estimate of the mass-specific cost during locomotion could be obtained by factoring in the effect of increased locomotor costs associated with relatively shorter pelvic limbs in larger lizards. The allometrically corrected estimate of the mass-specific cost during locomotion was proportional to mass(-0.31). This estimated regression, which is the relative cost of transport for a single, morphologically conservative Family of lizards, predicts a slope quite close to that derived from studies of oxygen requirements during locomotion in lizards of several families (slope = -0.28, John-Alder, Garland and Bennett, 1986) and in mammals (slope = -0.32, Taylor, Heglund and Maloiy, 1982). C1 SAVANNAH RIVER ECOL LAB, AIKEN, SC 29801 USA. RP SUNY COLL BUFFALO, DEPT BIOL, BUFFALO, NY 14222 USA. NR 57 TC 32 Z9 32 U1 1 U2 5 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0952-8369 EI 1469-7998 J9 J ZOOL JI J. Zool. PD MAY PY 1994 VL 233 BP 107 EP 128 PN 1 PG 22 WC Zoology SC Zoology GA NQ180 UT WOS:A1994NQ18000009 ER PT J AU ROBERTSON, MJ ANGELICI, RJ AF ROBERTSON, MJ ANGELICI, RJ TI ADSORPTION OF ARYL AND ALKYL ISOCYANIDES ON POWDERED GOLD SO LANGMUIR LA English DT Article ID CARBON-MONOXIDE; METAL-SURFACES; ALKANETHIOLATE MONOLAYERS; AU(110) SURFACE; OXYGEN; COPPER; CO; CHEMISORPTION; COMPLEXES; CH3NC AB Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) is used to examine the adsorption of phenyl isocyanide (PhNC), tert-butyl isocyanide (Bu(t)NC), and 1,4-phenylene diisocyanide (1,4-DINC) from methanol solution on gold powder. These studies indicate that the isocyanides bond end-on to a single gold atom through the terminal carbon atom of the isocyanide group. This structural assignment is based on a comparison of the nu(NC) values of the isocyanides adsorbed on gold with those in (PhNC)AuCl, (Bu(t)NC)AuCl, and isocyanide gold cluster compounds. The nu(NC) frequencies of the isocyanides typically shift 50-70 cm-1 higher upon adsorption to the gold powder when compared to the uncoordinated isocyanides. The spectra indicate that only one isocyanide group of 1,4-DINC coordinates to the gold; the other one remains uncoordinated. When the concentration of the isocyanide in the methanol is increased, the amount of isocyanide adsorbed increases up to a limiting value. At all loadings, the isocyanides bind to only one Au atom; there is no evidence for bridging RNC groups. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,GILMAN HALL,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. NR 61 TC 79 Z9 79 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY PY 1994 VL 10 IS 5 BP 1488 EP 1492 DI 10.1021/la00017a028 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA NN491 UT WOS:A1994NN49100029 ER PT J AU WILSON, TE SPEVAK, W CHARYCH, DH BEDNARSKI, MD AF WILSON, TE SPEVAK, W CHARYCH, DH BEDNARSKI, MD TI ENZYMATIC MODIFICATION AND X-RAY PHOTOELECTRON-SPECTROSCOPY ANALYSIS OF A FUNCTIONALIZED POLYDIACETYLENE THIN-FILM SO LANGMUIR LA English DT Article ID MONOLAYER ASSEMBLIES; SURFACES; INTERFACE; GOLD AB The mild conditions and specificity of biological catalysts are attractive incentives for their use in the formation of surfaces with well-defined chemical functionality. Herein, we describe the synthesis, characterization, and enzymatic modification of a functionalized polymeric bilayer assembly. The assembly is composed of a self-assembled monolayer of octadecylsilane and a Langmuir-Blodgett monolayer of polydiacetylene functionalized with the dipeptide phenylalanine-alanine (Phe-Ala). We demonstrate via X-ray photoelectron spectroscopy surface analysis that the surface-bound Phe-Ala dipeptide is a substrate for specific cleavage by the enzyme subtilisin BPN'. In-situ surface transformations via enzymatic synthesis or cleavage offer an alternative to chemical treatments of organic thin films. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RP CHARYCH, DH (reprint author), LAWRENCE BERKELEY LAB,DIV MAT SCI,CTR ADV MAT,BERKELEY,CA 94720, USA. NR 27 TC 17 Z9 17 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY PY 1994 VL 10 IS 5 BP 1512 EP 1516 DI 10.1021/la00017a031 PG 5 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA NN491 UT WOS:A1994NN49100032 ER PT J AU PYDA, M STANLEY, BJ XIE, M GUIOCHON, G AF PYDA, M STANLEY, BJ XIE, M GUIOCHON, G TI ANALYSIS OF THE SURFACE HETEROGENEITY OF UNMODIFIED AND MODIFIED SILICA BY CAPILLARY INVERSE GAS-SOLID CHROMATOGRAPHY AT FINITE DILUTION SO LANGMUIR LA English DT Article ID ADSORPTION-ISOTHERM DATA; ENERGY-DISTRIBUTION AB The adsorption energy distributions (AEDs) of several molecular probes on two silica samples were determined from their chromatographic retention data. Adsorption data were obtained using the elution-by-characteristic points (ECP) method of capillary inverse gas chromatography at finite dilution. The diffuse rear profiles of the bands obtained with samples of different sizes overlay consistently. The numerical expectation-maximization (EM) method has been applied to the calculation of the AEDs from the unfitted experimental adsorption isotherms, using the Langmuir model for the local adsorption isotherm. Two silica samples, both unmodified and reacted with trimethylchlorosilane, were used. Results were obtained with methanol, diethyl ether, 1-chlorobutane, dichloromethane, and toluene. Their AEDs exhibit two high-energy peaks, around 45-60 and 50-70 kJ/mol, respectively. The differences observed for the specific capacities of adsorption and for the energy distributions of the unmodified and modified silicas are correlated with the chemical structure of the probe and the adsorbent surface. C1 OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,OAK RIDGE,TN 37831. RP GUIOCHON, G (reprint author), UNIV TENNESSEE,DEPT CHEM,KNOXVILLE,TN 37996, USA. NR 17 TC 21 Z9 21 U1 2 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY PY 1994 VL 10 IS 5 BP 1573 EP 1579 DI 10.1021/la00017a041 PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA NN491 UT WOS:A1994NN49100042 ER PT J AU KING, DE CZANDERNA, AW AF KING, DE CZANDERNA, AW TI OXIDATION BEHAVIOR OF THIN COPPER-FILMS ON A MERCAPTOUNDECANOIC ACID ORGANIZED MOLECULAR ASSEMBLY SO LANGMUIR LA English DT Note RP KING, DE (reprint author), NATL RENEWABLE ENERGY LAB,1617 COLE BLVD,GOLDEN,CO 80401, USA. NR 8 TC 9 Z9 10 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAY PY 1994 VL 10 IS 5 BP 1630 EP 1631 DI 10.1021/la00017a052 PG 2 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA NN491 UT WOS:A1994NN49100053 ER PT J AU PAISNER, JA BOYES, JD KUMPAN, SA LOWDERMILK, WH SOREM, MS AF PAISNER, JA BOYES, JD KUMPAN, SA LOWDERMILK, WH SOREM, MS TI NATIONAL IGNITION FACILITY WOULD BOOST UNITED-STATES INDUSTRIAL COMPETITIVENESS SO LASER FOCUS WORLD LA English DT Editorial Material C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. UNIV ROCHESTER,LASER ENERGET LAB,ROCHESTER,NY 14627. RP PAISNER, JA (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 0 TC 90 Z9 90 U1 0 U2 1 PU PENNWELL PUBL CO PI NASHUA PA 5TH FLOOR TEN TARA BOULEVARD, NASHUA, NH 03062-2801 SN 0740-2511 J9 LASER FOCUS WORLD JI Laser Focus World PD MAY PY 1994 VL 30 IS 5 BP 75 EP 77 PG 3 WC Optics SC Optics GA NK624 UT WOS:A1994NK62400024 ER PT J AU RITCHIE, B BOLTON, P AF RITCHIE, B BOLTON, P TI INTERFERENCE OF FIELD AND SPECTRAL HARMONICS - ORIGIN OF THE BROAD PLATEAU IN STRONG-FIELD HARMONIC-GENERATION SO LASER PHYSICS LA English DT Article AB A quantum theory is presented for the broad plateau that appears in all laser-atom photoemission spectra. Theoretical evidence is presented that shows that the plateau is caused by the interference of lower order harmonics at the internal spectral frequencies of the atom with higher order harmonics at odd-order multiples of the frequency of the laser field. RP RITCHIE, B (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU INTERPERIODICA PI BIRMINGHAM PA PO BOX 1831, BIRMINGHAM, AL 35201-1831 SN 1054-660X J9 LASER PHYS JI Laser Phys. PD MAY-JUN PY 1994 VL 4 IS 3 BP 588 EP 591 PG 4 WC Optics; Physics, Applied SC Optics; Physics GA NT581 UT WOS:A1994NT58100023 ER PT J AU GE, Z SCOVEL, C AF GE, Z SCOVEL, C TI HAMILTONIAN TRUNCATION OF THE SHALLOW-WATER EQUATION SO LETTERS IN MATHEMATICAL PHYSICS LA English DT Article ID SYMPLECTIC INTEGRATION; SYSTEMS; HYDRODYNAMICS; CONSTRUCTION; MECHANICS; REDUCTION; BRACKETS; SCHEMES AB In this Letter, we describe a truncation of the Eulerian description of the shallow water equation of climate modeling to a finite-dimensional Hamiltonian system. The technique is to use an isomorphism from a semidirect product Poisson manifold to a direct product of Poisson manifolds, both of whose components are truncatable to finite-dimensional Poisson manifolds, based on Moser's theorem on volume elements. C1 LOS ALAMOS NATL LAB,COMP RES GRP,LOS ALAMOS,NM 87545. RP GE, Z (reprint author), FIELDS INST RES MATH SCI,185 COLUMBIA ST W,WATERLOO N2L 5Z5,ON,CANADA. NR 41 TC 2 Z9 2 U1 0 U2 1 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0377-9017 J9 LETT MATH PHYS JI Lett. Math. Phys. PD MAY PY 1994 VL 31 IS 1 BP 1 EP 13 PG 13 WC Physics, Mathematical SC Physics GA NL566 UT WOS:A1994NL56600001 ER PT J AU RITCHIE, RO DAUSKARDT, RH RAO, KTV AF RITCHIE, RO DAUSKARDT, RH RAO, KTV TI FATIGUE-CRACK PROPAGATION BEHAVIOR IN MONOLITHIC AND COMPOSITE CERAMICS AND INTERMETALLICS SO MATERIALS SCIENCE LA English DT Article ID PARTIALLY-STABILIZED ZIRCONIA; CYCLIC FATIGUE; GROWTH BEHAVIOR; ALUMINA; FRACTURE; MECHANISMS; TEMPERATURES; ALLOYS; LOADS; ZONES AB We study microstructural mechanisms of fatigue crack growth in advanced monolithic and composite ceramics and intermetallics. Much attention is devoted to the contribution of cycling loading to the hindrance of mechanisms that lead to a considerable increase in toughness (crack-tip shielding) of these materials. For example, in intermetallics with a ductile phase, such as beta-TiNb-reinforced gamma-TiAl or Nb-reinforced Nb3Al, a significant increase in toughness caused by the presence of uncracked ductile phase inside a crack is retarded under cyclic loading because ductile particles immediately fail by fatigue. Similarly, in monolithic ceramics, e.g., in alumina (aluminum oxide) or silicon nitride, the significant plasticization appearing under monotonic loading is greatly diminished under cyclic loading due to gradual wear at the grain-matrix interface. In fact, the nature of fatigue in such low-plasticity materials differs essentially from the well-known mechanisms of fatigue in metals and is governed, first of all, by a decrease in shielding, which depends on the loading cycle and time. The susceptibility of intermetallics and ceramics to fatigue degradation under cyclic loading affects seriously the possibility of structural use of these materials in practice. In particular, in this case, it is difficult to apply strength calculation methods that take into account the presence of defects and to implement life-prediction procedures. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,CTR ADV MAT,BERKELEY,CA 94720. RI Ritchie, Robert/A-8066-2008 OI Ritchie, Robert/0000-0002-0501-6998 NR 65 TC 1 Z9 1 U1 0 U2 2 PU PLENUM PUBL CORP PI NEW YORK PA CONSULTANTS BUREAU 233 SPRING ST, NEW YORK, NY 10013 SN 1068-820X J9 MATER SCI+ JI Mater. Sci. PD MAY-JUN PY 1994 VL 30 IS 3 BP 277 EP 300 PG 24 WC Materials Science, Multidisciplinary SC Materials Science GA TH429 UT WOS:A1994TH42900001 ER PT J AU KURZ, W TRIVEDI, R AF KURZ, W TRIVEDI, R TI RAPID SOLIDIFICATION PROCESSING AND MICROSTRUCTURE FORMATION SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 8th International Conference on Rapidly Quenched and Metastable Materials CY AUG 22-27, 1993 CL SENDAI, JAPAN SP JAPAN INST MET, MIYAGI PREFECTURE, IND DEV PROMOT DIV, SENDAI CONVENT BUR, KAJIMA FDN, RES FDN MAT SCI ID LAMELLAR EUTECTIC GROWTH; AL-FE ALLOYS; DENDRITIC GROWTH; CU ALLOYS; FLOW; POWDER; MELTS; HEAT AB An overview of rapid solidification is undertaken and various rapid solidification processes are grouped into three classes. This leads to a better understanding of the similarities and differences between the various methods in terms of solidification parameters. Microstructures (with specific attention to rapid laser treatment) are analysed and various microstructure selection maps are presented. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT MAT SCI & ENGN,AMES,IA 50011. RP KURZ, W (reprint author), SWISS FED INST TECHNOL,DEPT MAT,CH-1015 LAUSANNE,SWITZERLAND. NR 35 TC 62 Z9 62 U1 5 U2 26 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD MAY 1 PY 1994 VL 179 BP 46 EP 51 DI 10.1016/0921-5093(94)90162-7 PG 6 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA NN060 UT WOS:A1994NN06000011 ER PT J AU SCHWARZ, RB RUBIN, JB AF SCHWARZ, RB RUBIN, JB TI ELASTIC PROPERTIES OF AMORPHOUS THIN-FILMS STUDIED USING RAYLEIGH-WAVES SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 8th International Conference on Rapidly Quenched and Metastable Materials CY AUG 22-27, 1993 CL SENDAI, JAPAN SP JAPAN INST MET, MIYAGI PREFECTURE, IND DEV PROMOT DIV, SENDAI CONVENT BUR, KAJIMA FDN, RES FDN MAT SCI ID THERMODYNAMIC FUNCTIONS; ASSOCIATION MODEL; METALLIC GLASSES; LIQUID ALLOYS; NI AB Physical vapor deposition in an ultrahigh vacuum was used to codeposit nickel and zirconium onto quartz single crystals and grow amorphous Ni1 -xZrx (0.1 < x < 0.8 7) thin films. A high resolution surface acoustic wave technique was developed for the in situ measurement of the film shear moduli. The modulus has narrow maxima at x = 0.17, 0.22, 0.43, 0.5, 0.63 and 0.72, reflecting short-range ordering and the formation of aggregates in the amorphous phase. It is proposed that the aggregates correspond to polytetrahedral atom arrangements which are limited in size by geometrical ''frustration''. RP SCHWARZ, RB (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,MAIL STOP K765,LOS ALAMOS,NM 87545, USA. NR 22 TC 1 Z9 1 U1 2 U2 6 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD MAY 1 PY 1994 VL 179 BP 137 EP 141 DI 10.1016/0921-5093(94)90180-5 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA NN060 UT WOS:A1994NN06000029 ER PT J AU THOMA, DJ PEREPEZKO, JH PLANTZ, DH SCHWARZ, RB AF THOMA, DJ PEREPEZKO, JH PLANTZ, DH SCHWARZ, RB TI METASTABLE BCC PHASE-FORMATION IN THE NB-CR SYSTEM SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT 8th International Conference on Rapidly Quenched and Metastable Materials CY AUG 22-27, 1993 CL SENDAI, JAPAN SP JAPAN INST MET, MIYAGI PREFECTURE, IND DEV PROMOT DIV, SENDAI CONVENT BUR, KAJIMA FDN, RES FDN MAT SCI ID MECHANICAL-PROPERTIES; ALLOYS AB Extended metastable b.c.c. solid solutions of Nb-Xat.%Cr (X= 35, 50, 57, 77, 82 and 94) were synthesized by two-anvil splat-quenching. In addition, b.c.c. Nb-67at.%Cr was prepared by mechanically alloying mixtures of niobium and chromium powders. The lattice parameters were measured by X-rav diffraction and the Young's moduli by low load micro-indentation. The composition dependence of the lattice parameters and elastic moduli shows a positive deviation with respect to a rule of mixtures. During continuous heating at 15-degrees-C min-1, the metastable precursor b.c.c. phases decomposed at temperatures above 750-degrees-C to uniformly refined microstructures. C1 US COAST GUARD ACAD,DEPT ENGN,NEW LONDON,CT 06320. UNIV WISCONSIN,DEPT MAT SCI & ENGN,MADISON,WI 53706. RP THOMA, DJ (reprint author), LOS ALAMOS NATL LAB,CTR MAT SCI,MAIL STOP K765,LOS ALAMOS,NM 87545, USA. NR 18 TC 12 Z9 14 U1 0 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD MAY 1 PY 1994 VL 179 BP 176 EP 180 DI 10.1016/0921-5093(94)90188-0 PG 5 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA NN060 UT WOS:A1994NN06000037 ER PT J AU NASTASI, M MAYER, JW AF NASTASI, M MAYER, JW TI ION-BEAM MIXING IN METALLIC AND SEMICONDUCTOR-MATERIALS SO MATERIALS SCIENCE & ENGINEERING R-REPORTS LA English DT Review ID METASTABLE PHASE FORMATION; MOLECULAR-DYNAMICS; TEMPERATURE-DEPENDENCE; DISPLACEMENT CASCADES; SILICIDE FORMATION; FRACTAL-GEOMETRY; COHESIVE ENERGY; THERMAL SPIKES; THIN-FILMS; BILAYERS AB In this review we shall describe and discuss the basics of the ion mixing phenomenon. First, the process is examined by considering only ballistic and kinematic effects associated with collisions between projectile and target atoms. We shall examine how collision cascades and the evolution of dense energy spikes affect the mixing process. We then show material properties, such as heat of mixing and cohesive energy, influence the mixing process. These properties lead to the physical basis for the occurrence of temperature-independent and temperature-dependent mixing regimes. Finally, we shall examine the phase formation possibilities in the ion-reacted layer, and how irradiation conditions and various material properties can influence the final structure that forms. C1 ARIZONA STATE UNIV,CTR SOLID STATE SCI,TEMPE,AZ 85207. RP NASTASI, M (reprint author), LOS ALAMOS NATL LAB,DIV MAT SCI & TECHNOL,LOS ALAMOS,NM 87545, USA. NR 120 TC 163 Z9 164 U1 1 U2 14 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0927-796X J9 MAT SCI ENG R JI Mater. Sci. Eng. R-Rep. PD MAY PY 1994 VL 12 IS 1 BP 1 EP 52 DI 10.1016/0927-796X(94)90005-1 PG 52 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA NP919 UT WOS:A1994NP91900001 ER PT J AU IVANOVIC, M WEBER, DA LONCARIC, S FRANCESCHI, D AF IVANOVIC, M WEBER, DA LONCARIC, S FRANCESCHI, D TI FEASIBILITY OF DUAL RADIONUCLIDE BRAIN IMAGING WITH I-123 AND TC-99M SO MEDICAL PHYSICS LA English DT Article ID SPECT; SCATTER; TL-201; VALIDATION; EMISSION; DETECTOR; PHANTOM; ENERGY AB A study was conducted to evaluate the feasibility of simultaneous dual radionuclide brain imaging with I-123 and Tc-99m using photopeak image subtraction techniques or offset photopeak image acquisition. The contribution of the photons from one radionuclide to a second radionuclide's photopeak energy window (crosstalk) was evaluated for SPECT and planar imaging of a brain phantom containing I-123 and Tc-99m for a range of activity levels and distribution properties approximating those in rCBF images of the adult human brain. Crosstalk was evaluated for 10% symmetrical energy windows centered on the I-123 and Tc-99m photopeaks and for 10% energy windows asymmetrically placed to the left and right of the center of the respective photopeaks. Major observations include: (1) in the centered photopeak windows, Tc-99m crosstalk in the I-123 window is 8.9% of the Tc-99m seen in the Tc-99m window and ranges from 37.5% to 75.0% of the I-123 in the I-123 window. I-123 crosstalk is 37.8% of the I-123 seen in the I-123 window and ranges from 4.4% to 8.9% of the Tc-99m seen in the Tc-99m window; (2) the spatial distribution of a radionuclide's crosstalk photons differs from that observed in the radionuclide's photopeak window; (3) a Tc-99m photopeak window offset to the left does not decrease I-123 crosstalk, and the percentage of Tc-99m scattered photons is significantly increased in the window. Offsetting the I-123 window to the right decreases Tc-99m crosstalk to 9.0% to 17.9% of the I-123 counts, but decreases I-123 sensitivity by 39.9%; and (4) offsetting both photopeak windows to the right decreases the Tc-99m scattered photons in the Tc-99m window, but increases I-123 crosstalk to 17.0% to 33.8% of the Tc-99m counts. The findings show that,image quality, spatial resolution, and quantitative accuracy are degraded to unacceptable levels with the combinations of energy windows tested for dual radionuclide imaging of Tc-99m and I-123. This indicates that dual radionuclide imaging must be thoroughly tested and validated before use in clinical studies. C1 RUSH PRESBYTERIAN ST LUKES MED CTR,CHICAGO,IL 60612. RP IVANOVIC, M (reprint author), BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973, USA. NR 24 TC 36 Z9 36 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0094-2405 J9 MED PHYS JI Med. Phys. PD MAY PY 1994 VL 21 IS 5 BP 667 EP 674 PG 8 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NM426 UT WOS:A1994NM42600006 PM 7935202 ER PT J AU WILLIAMS, PT KRAUSS, RM STEFANICK, ML VRANIZAN, KM WOOD, PD AF WILLIAMS, PT KRAUSS, RM STEFANICK, ML VRANIZAN, KM WOOD, PD TI EFFECTS OF LOW-FAT DIET, CALORIE RESTRICTION, AND RUNNING ON LIPOPROTEIN SUBFRACTION CONCENTRATIONS IN MODERATELY OVERWEIGHT MEN SO METABOLISM-CLINICAL AND EXPERIMENTAL LA English DT Article ID HIGH-DENSITY-LIPOPROTEINS; GRADIENT GEL-ELECTROPHORESIS; INDUCED WEIGHT-LOSS; PLASMA-LIPOPROTEINS; PARTICLE-SIZE; A-I; CHOLESTEROL ACYLTRANSFERASE; MYOCARDIAL-INFARCTION; EXERCISE; INGESTION C1 STANFORD UNIV, SCH MED, STANFORD CTR RES DIS PREVENT, STANFORD, CA 94305 USA. RP WILLIAMS, PT (reprint author), UNIV CALIF BERKELEY, LAWRENCE BERKELEY LAB, DIV LIFE SCI HL49828, BLDG 934, 1 CYCLOTRON RD, BERKELEY, CA 94720 USA. FU NHLBI NIH HHS [HL-02183, HL-24462, HL-49828]; NIA NIH HHS [R03 AG032004-01A1, R03 AG032004] NR 53 TC 39 Z9 39 U1 0 U2 5 PU W B SAUNDERS CO-ELSEVIER INC PI PHILADELPHIA PA 1600 JOHN F KENNEDY BOULEVARD, STE 1800, PHILADELPHIA, PA 19103-2899 USA SN 0026-0495 EI 1532-8600 J9 METABOLISM JI Metab.-Clin. Exp. PD MAY PY 1994 VL 43 IS 5 BP 655 EP 663 DI 10.1016/0026-0495(94)90210-0 PG 9 WC Endocrinology & Metabolism SC Endocrinology & Metabolism GA NL244 UT WOS:A1994NL24400021 PM 8177056 ER PT J AU WRIGHT, SI GRAY, GT ROLLETT, AD AF WRIGHT, SI GRAY, GT ROLLETT, AD TI TEXTURAL AND MICROSTRUCTURAL GRADIENT EFFECTS ON THE MECHANICAL-BEHAVIOR OF A TANTALUM PLATE SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID DEFORMATION; SILICON; STEEL AB The effects of gradients in the texture and microstructure of a tantalum plate on mechanical behavior are examined. In particular, the effects of variations in grain size and texture from the surface of the plate to the centerline on the yield behavior and final shape of compression samples are investigated. Individual lattice orientations were measured on samples both before and after deformation using automatic analysis of electron backscatter diffraction patterns. These data were used as input to a polycrystal plasticity model based on the Taylor assumption of uniform strain. Results are compared from experimental and simulated compression tests. The effects of the texture and grain size gradients on these results are discussed. The influence of the texture gradient was found to be the dominating factor controlling the nonuniform plastic response of the material. This work also demonstrates the capability of currently available tools for characterizing inhomogeneous microstructures and modeling the effects of variations in texture and microstructure on mechanical behavior. RP WRIGHT, SI (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Rollett, Anthony/A-4096-2012 OI Rollett, Anthony/0000-0003-4445-2191 NR 23 TC 37 Z9 38 U1 0 U2 4 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD MAY PY 1994 VL 25 IS 5 BP 1025 EP 1031 DI 10.1007/BF02652277 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA NJ562 UT WOS:A1994NJ56200013 ER PT J AU ALMAN, DE STOLOFF, NS AF ALMAN, DE STOLOFF, NS TI THE EFFECT OF NB MORPHOLOGY ON THE CYCLIC OXIDATION RESISTANCE OF MOSI2/20 VOL PCT NB COMPOSITES SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID INTERMETALLIC COMPOSITES; MOLYBDENUM DISILICIDE; POLYCRYSTALLINE MOSI2; FRACTURE TOUGHNESS; STRENGTH AB The effect of Nb morphology on the 1200-degrees-C cyclic oxidation resistance of MoSi2/20 vol pct Nb composites was investigated. Niobium was incorporated into MoSi2 as particles, random short fibers, and continuous aligned fibers. After oxidation, it was found that all the composites had lost weight and essentially disintegrated. This was attributed to spalling of both the Nb2O5 scale and the MoSi2 matrix. The spalling of the matrix was a result of cracks originating in the oxidized Nb and propagating through the MoSi2 matrix. These cracks arose from two sources: (1) the volume expansion associated with the transformation of Nb to Nb2O5 and (2) the difference in thermal expansion between Nb2O5 and MoSi2. However, it was found that the addition of smaller diameter Nb reinforcements tended to retard the disintegration of the composites. This was attributed to the effect of reinforcement size on CTE mismatch cracking. C1 US BUR MINES,ALBANY RES CTR,ALBANY,OR 97321. RP ALMAN, DE (reprint author), RENSSELAER POLYTECH INST,DEPT MAT ENGN,TROY,NY 12180, USA. NR 30 TC 5 Z9 5 U1 0 U2 0 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD MAY PY 1994 VL 25 IS 5 BP 1033 EP 1040 DI 10.1007/BF02652278 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA NJ562 UT WOS:A1994NJ56200014 ER PT J AU BASKES, MI ANGELO, JE BISSON, CL AF BASKES, MI ANGELO, JE BISSON, CL TI ATOMISTIC CALCULATIONS OF COMPOSITE INTERFACES SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article ID EMBEDDED-ATOM POTENTIALS; METALS; IMPURITIES; SILICON; NISI2; COSI2 AB The modified embedded atom method (MEAM), an empirical extension of the embedded atom method (EAM) that includes angular forces, has been used to examine the interface between a silicon substrate and a thin overlayer of nickel. A brief review of the MEAM is given and parameters are determined for the Si-Ni system. As verification of the reliability of the model, the geometry, energy and elastic constants of a number of ideal Si-Ni compounds are calculated and are found to agree reasonably well with experiment and first-principles calculations. Planar defect energies are also presented. Calculations of the relaxed energy and geometry of a coherent 10 angstrom overlayer of Ni on Si(001) yield two similar structures, both of which were typified by a slightly rippled Ni structure relative to perfect FCC Ni. The lower-energy interface also contained rows of slightly shifted Ni atoms. It is found that significant differences occur between the energetics of a rigid or relaxed separation of the overlayer. Separation of the overlayer with a monolayer of Si atoms attached to the Ni yields a significantly lower-energy structure than separation exactly at the interface. The relaxed brittle fracture energy of this interface is found to be 1.5 J m-2, which is significantly lower than the unrelaxed fracture energy of 4.8 J m-2. RP BASKES, MI (reprint author), SANDIA NATL LABS, LIVERMORE, CA 94550 USA. NR 27 TC 116 Z9 118 U1 3 U2 29 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD MAY PY 1994 VL 2 IS 3A BP 505 EP 518 DI 10.1088/0965-0393/2/3A/006 PG 14 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA NV326 UT WOS:A1994NV32600007 ER PT J AU SILLING, SA TAYLOR, PA AF SILLING, SA TAYLOR, PA TI THE SIMULATION OF COMPOSITE-MATERIAL RESPONSE UNDER DYNAMIC COMPRESSIVE LOADING SO MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING LA English DT Article; Proceedings Paper CT IUTAM Symposium on Computational Mechanics of Materials CY JUN 15-18, 1993 CL BROWN UNIV, PROVIDENCE, RI SP INT UNION THEORET & APPL MECH HO BROWN UNIV AB Realistic computer prediction of high-velocity impact and penetration events involving composite materials requires a knowledge of the material behaviour under large compressive stresses at high rates of deformation. As an aid to the development of constitutive models for composites under these conditions, methods for numerical simulation of the material response at the microstructural level are being developed. At present, the study is confined to glass fiber/epoxy composites. The technique uses a numerical model of a representative sample of the microstructure with randomly distributed fibers. By subjecting the boundary of this numerical sample to prescribed loading histories, a statistical interpretation allows prediction of the global material response. Because the events at the microstructural scale involve locally large deformation, and because of the constantly changing picture with regard to contact between the fibers, the Eulerian code CTH is used for these calculations. Certain aspects of material failure can also be investigated using this approach. The method allows the mechanical behavior of composite materials to be studied with fewer assumptions about constituent behavior and morphology than are typically required in analytical efforts. RP SILLING, SA (reprint author), SANDIA NATL LABS,DEPT COMP PHYS & MECH,1432,ALBUQUERQUE,NM 87185, USA. NR 7 TC 1 Z9 1 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0965-0393 J9 MODEL SIMUL MATER SC JI Model. Simul. Mater. Sci. Eng. PD MAY PY 1994 VL 2 IS 3A BP 689 EP 699 DI 10.1088/0965-0393/2/3A/018 PG 11 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA NV326 UT WOS:A1994NV32600019 ER PT J AU CHANG, LY YEN, CP BESL, L SCHELL, M SOLOMON, A AF CHANG, LY YEN, CP BESL, L SCHELL, M SOLOMON, A TI IDENTIFICATION AND CHARACTERIZATION OF A FUNCTIONAL HUMAN IG V-LAMBDA-VI GERMLINE GENE SO MOLECULAR IMMUNOLOGY LA English DT Article DE LAMBDA LIGHT CHAINS; AMYLOIDOSIS; BENCE JONES PROTEIN; GENE EXPRESSION ID MOLECULAR CHARACTERIZATION; SEQUENCE-ANALYSIS; GENOMIC SEQUENCE; REGION SUBGROUPS; LIGHT-CHAINS; EXPRESSION; PROTEIN; ELEMENTS; KAPPA; ASSOCIATION AB We have isolated from a human genomic library a potentially functional and distinctive germline gene, designated IGLV6S1, that encodes for light chains of the V-lambda VI subgroup. An identical germline gene was cloned from fibroblasts obtained from a patient with light-chain-associated amyloidosis (AL amyloidosis) whose serum and urine contained, respectively, a monoclonal IgG lambda VI protein and a lambda VI Bence Jones protein. Isolation and characterization of cDNA cloned from the patient's bone marrow-derived monoclonal plasma cells revealed that the nucleotide and predicted protein sequences of the rearranged gene were similar to 95% and similar to 90% homologous to those of the germline gene, respectively. The finding that the transcriptional start site for lambda VI RNA synthesis was located upstream of the putative TATA-box promoter, rather than downstream as found for the V-lambda II subgroup, implies that a different transcriptional machinery controls the expression of the human V-lambda VI-gene family. C1 UNIV TENNESSEE,OAK RIDGE GRAD SCH BIOMED SCI,OAK RIDGE,TN 37931. RP CHANG, LY (reprint author), UNIV TENNESSEE,MED CTR,GRAD SCH MED,DEPT MED,HUMAN IMMUNOL & CANC PROGRAM,1924 ALCOA HIGHWAY,KNOXVILLE,TN 37920, USA. FU NCI NIH HHS [CA10056] NR 35 TC 27 Z9 28 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0161-5890 J9 MOL IMMUNOL JI Mol. Immunol. PD MAY PY 1994 VL 31 IS 7 BP 531 EP 536 PG 6 WC Biochemistry & Molecular Biology; Immunology SC Biochemistry & Molecular Biology; Immunology GA NN223 UT WOS:A1994NN22300004 PM 8190128 ER PT J AU LEGANES, F FERNANDEZPINAS, F WOLK, CP AF LEGANES, F FERNANDEZPINAS, F WOLK, CP TI 2 MUTATIONS THAT BLOCK HETEROCYST DIFFERENTIATION HAVE DIFFERENT EFFECTS ON AKINETE DIFFERENTIATION IN NOSTOC-ELLIPSOSPORUM SO MOLECULAR MICROBIOLOGY LA English DT Article ID SP-STRAIN PCC-7120; CYANOBACTERIUM ANABAENA; NITROGEN-FIXATION; MUTANTS; GENE; COMPLEMENTATION; POLYSACCHARIDES; EXPRESSION; ENVELOPES AB Evident differentiation of Vegetative cells into heterocysts in Anabaena sp. strain PCC 7120 is prevented by insertions in genes hetR and hetP. Nostoc ellipsosporum possesses single copies of genes that hybridize with hetR and hetP. In mutant NE2 of H ellipsosporum, in which hetR is interrupted by an insert, and in a double recombinant of wild-type N. ellipsosporum with a plasmid that bears an interrupted copy of hetR, neither heterocysts nor akinetes are formed. When an intact copy of hetR from Anabaena sp. strain PCC 7120 was added to NE2 the ability to form both heterocysts and akinetes was restored. In contrast to the hetR mutant, a hetP mutant of N. ellipsosperum could form akinetes, but heterocyst formation was blocked. Use of luxAB, encoding luciferase, as a reporter, and use of luxC, luxD and luxE to generate aldehyde (a substrate for the luciferase reaction), permitted visualization of the expression of hetR at the level of single cells; hetR was expressed in akinetes. C1 MICHIGAN STATE UNIV,US DOE,PLANT RES LAB,E LANSING,MI 48824. NR 30 TC 38 Z9 39 U1 0 U2 0 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0950-382X J9 MOL MICROBIOL JI Mol. Microbiol. PD MAY PY 1994 VL 12 IS 4 BP 679 EP 684 DI 10.1111/j.1365-2958.1994.tb01055.x PG 6 WC Biochemistry & Molecular Biology; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA NL733 UT WOS:A1994NL73300017 PM 7934891 ER PT J AU DAWSON, LR PICRAUX, ST AF DAWSON, LR PICRAUX, ST TI BANDGAPS OF COMPOUND SEMICONDUCTOR ALLOYS SO MRS BULLETIN LA English DT Article RP DAWSON, LR (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI PITTSBURGH PA 9800 MC KNIGHT ROAD SUITE 327, PITTSBURGH, PA 15237 SN 0883-7694 J9 MRS BULL JI MRS Bull. PD MAY PY 1994 VL 19 IS 5 BP 45 EP 45 PG 1 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA NM114 UT WOS:A1994NM11400008 ER PT J AU MENICHINI, P MROCZKOWSKA, MM SINGER, B AF MENICHINI, P MROCZKOWSKA, MM SINGER, B TI ENZYME-DEPENDENT PAUSING DURING IN-VITRO REPLICATION OF O-4-METHYLTHYMINE IN A DEFINED OLIGONUCLEOTIDE SEQUENCE SO MUTATION RESEARCH LA English DT Article DE DNA ADDUCT; DNA POLYMERASE I, ESCHERICHIA-COLI, LARGE FRAGMENT; T7 POLYMERASE; DNA POLYMERASE ALPHA-PRIMASE, CALF-THYMUS; SEQUENASE; POLYMERASE TRAPPING; O-4-METHYLTHYMINE; OLIGONUCLEOTIDE SEQUENCE ID BACTERIOPHAGE-T7 DNA-POLYMERASE; I KLENOW FRAGMENT; ESCHERICHIA-COLI; EXTENSION KINETICS; PYRIMIDINES; MUTAGENESIS; REPAIR; ALPHA; SITE; RATS AB We had previously reported that an oligonucleotide containing a site-specifically incorporated O-4-methylthymine (m(4)T) was replicated under kinetic conditions by the Klenow fragment of E. coli DNA polymerase I (Kf) (Dosanjh et al., 1993). Using other polymerases for complete replication, but with limiting enzyme, a pause site before the m(4)T was observed. In order to investigate whether such a pause could be due to enzyme dissociation or stalling, trapping experiments were designed to aid in differentiating the two mechanisms. Rather than the generally used heparin or sheared DNA trap, these experiments utilized as the acceptor the same oligonucleotide containing unmodified thymine. It was observed that, under enzyme-limiting conditions, the nature of the enzyme played a major role in replication of m(4)T. With a running start, Kf and calf-thymus polymerase ol-primase allowed replication beyond the m(4)T, while Sequenase and T7 showed a strong pause site at the base before m(4)T. When the oligonucleotide trap was added after different times of replication, it was found that Sequenase remained bound to the template-primer, regardless of whether T or m(4)T was present. In contrast, Kf dissociated and re-associated rapidly. Thus, m(4)T appears to be a strong replication block when using limiting amounts of a highly processive enzyme such as Sequenase or T7. This may imply that such enzymes discriminate against forming a poor basepair but remain bound to the primer-template or become inactivated. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DONNER LAB,DIV LIFE SCI,BERKELEY,CA 94720. FU NCI NIH HHS [CA 47723] NR 26 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8262 J9 MUTAT RES PD MAY 1 PY 1994 VL 307 IS 1 BP 53 EP 59 DI 10.1016/0027-5107(94)90277-1 PG 7 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA NK025 UT WOS:A1994NK02500007 PM 7513824 ER PT J AU HOFFMANN, GR SAYER, AM LITTLEFIELD, LG AF HOFFMANN, GR SAYER, AM LITTLEFIELD, LG TI POTENTIATION OF BLEOMYCIN BY THE AMINOTHIOL WR-1065 IN ASSAYS FOR CHROMOSOMAL DAMAGE IN G(0) HUMAN-LYMPHOCYTES SO MUTATION RESEARCH LA English DT Article DE BLEOMYCIN; WR-1065; AMINOTHIOL; RADIOPROTECTOR; MICRONUCLEUS; ABERRATIONS; FISH; CHROMOSOME PAINTING; LYMPHOCYTES; G(0) ID HUMAN PERIPHERAL LYMPHOCYTES; CO-60 GAMMA-RAY; V79 CELLS; 2-<(AMINOPROPYL)AMINO> ETHANETHIOL; INSITU HYBRIDIZATION; MAMMALIAN-CELLS; RADIATION; DNA; MECHANISMS; WR-2721 AB The aminothiol radioprotector WR-1065 potentiates the induction of chromosome aberrations and micronuclei by the chemotherapy drug bleomycin in G(0) human lymphocytes. Potentiation by 5 mM WR-1065 was observed at bleomycin concentrations from 0.1 to 100 mu g/ml in a 2-h treatment. The frequencies of micronuclei induced by bleomycin in the presence of WR-1065 reached that of 500-fold higher concentrations of bleomycin alone. The potential therapeutic implications of these findings are discussed. C1 OAK RIDGE INST SCI & EDUC,DIV MED SCI,OAK RIDGE,TN. RP HOFFMANN, GR (reprint author), COLL HOLY CROSS,DEPT BIOL,WORCESTER,MA 01610, USA. FU NCI NIH HHS [NCI CA 51388] NR 35 TC 21 Z9 22 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8262 J9 MUTAT RES PD MAY 1 PY 1994 VL 307 IS 1 BP 273 EP 283 DI 10.1016/0027-5107(94)90301-8 PG 11 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA NK025 UT WOS:A1994NK02500031 PM 7513807 ER PT J AU SETLOW, RB WOODHEAD, AD AF SETLOW, RB WOODHEAD, AD TI TEMPORAL CHANGES IN THE INCIDENCE OF MALIGNANT-MELANOMA - EXPLANATION FROM ACTION SPECTRA SO MUTATION RESEARCH LA English DT Article DE VISIBLE LIGHT; UV-RADIATION; ERYTHEMA; SUNSCREENS; FISH ID ULTRAVIOLET-RADIATION; HUMAN-SKIN; MONODELPHIS-DOMESTICA; CUTANEOUS MELANOMA; UNITED-STATES; ERYTHEMA; CANCER; WAVELENGTHS; EXPERIENCE; QUEENSLAND AB The incidence of malignant cutaneous melanoma has been increasing for more than 50 years, and is now rising more rapidly than that of any other cancer. This increase is not explicable by changes in the physical environment, particularly by any observed increase in UVB radiation (290-320 nm). The distribution of melanomas on the body differs from the site distribution of nonmelanoma skin cancer (relatively many more melanomas occur on areas of the body not chronically exposed to sunlight, such as the back of the trunk in males, and the legs in females). This localization of melanoma, together with its epidemiology, suggest that a change in lifestyle has contributed to the fast-rising incidence in many countries. There is no convenient mammalian animal model for malignant melanoma. However, certain inter- and intra-specific hybrids of fish of the genus Xiphophorus are very sensitive to light-induced melanomas; we have used them to determine the wavelengths effective in melanoma induction. The action spectrum has a relatively very large component in the UVA region (320-400 nm) compared to human erythema. Hence, if the human and fish spectra were similar, the use of sunscreens that minimize erythema would have little effect in preventing the induction of melanoma, and if people using sunscreens expose themselves to sunlight for longer periods, they will be increasing dramatically their exposure to these melanoma-inducing wavelengths. Such considerations are sufficient to explain the rising incidence of malignant melanoma and its distribution on the body. RP SETLOW, RB (reprint author), BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973, USA. NR 42 TC 72 Z9 72 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-8262 J9 MUTAT RES PD MAY 1 PY 1994 VL 307 IS 1 BP 365 EP 374 DI 10.1016/0027-5107(94)90310-7 PG 10 WC Genetics & Heredity; Toxicology SC Genetics & Heredity; Toxicology GA NK025 UT WOS:A1994NK02500040 PM 7513817 ER PT J AU SCHIPPER, L PRICE, L AF SCHIPPER, L PRICE, L TI EFFICIENT ENERGY USE AND WELL-BEING - THE SWEDISH EXAMPLE AFTER 20 YEARS SO NATURAL RESOURCES FORUM LA English DT Article ID OECD COUNTRIES; IMPACTS AB This paper reviews the evolution of energy use in Sweden since the early 1970s to shed light on the future, with emphasis on the role of energy efficiency. Between 1973 and 1989 improvements in end-use energy efficiency saved 8% of Sweden's primary energy use and 24% of Sweden's delivered energy use. These savings were concentrated in the residential and manufacturing sectors, with important savings also occurring in air travel and the heating of commercial buildings. Despite these accomplishments, we found that Sweden was well behind Denmark, FRGermany, Japan and the USA in energy savings during this period. At the beginning of the 1990s Sweden exhibited one of the most energy intensive economic structures in the OECD. Sweden now faces many dilemmas that will influence future energy use: the role of nuclear power, pricing and taxation policies for fuels and electricity, the future of subsidies for housing and travel, the role of Sweden's energy intensive exports, and indeed the very lifestyle of the Swedes. RP SCHIPPER, L (reprint author), LAWRENCE BERKELEY LAB,INT ENERGY STUDIES,4000 BLDG 90,BERKELEY,CA 94720, USA. NR 21 TC 12 Z9 12 U1 2 U2 3 PU BUTTERWORTH-HEINEMANN LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, OXON, ENGLAND OX5 1GB SN 0165-0203 J9 NAT RESOUR FORUM PD MAY PY 1994 VL 18 IS 2 BP 125 EP 142 PG 18 WC Environmental Sciences; Environmental Studies SC Environmental Sciences & Ecology GA NQ506 UT WOS:A1994NQ50600005 ER PT J AU EBERLING, JL RICHARDSON, BC REED, BR WOLFE, N JAGUST, WJ AF EBERLING, JL RICHARDSON, BC REED, BR WOLFE, N JAGUST, WJ TI CORTICAL GLUCOSE-METABOLISM IN PARKINSONS-DISEASE WITHOUT DEMENTIA SO NEUROBIOLOGY OF AGING LA English DT Article DE PARKINSONS DISEASE; PET; GLUCOSE METABOLISM; F-18-FLUORODEOXYGLUCOSE; HYPOMETABOLISM ID CEREBRAL BLOOD-FLOW; COMPLEX-I DEFICIENCY; EMISSION COMPUTED-TOMOGRAPHY; ALZHEIMERS-DISEASE; 1-METHYL-4-PHENYL-1,2,3,6-TETRAHYDROPYRIDINE MPTP; BRAIN MITOCHONDRIA; OXYGEN-METABOLISM; DEMENTIA; SPECT; PET AB There have been several reports of decreased regional cerebral metabolic rates for glucose (rCMRglc) in Parkinson's disease (PD), although others find no differences between PD patients and controls. Differences in the cognitive status of the PD patients may account for some of these inconsistencies. We report the results of a PET study using F-18-fluorodeoxyglucose (FDG) to measure rCMRglc in eight nondemented PD patients, six of whom were receiving dopaminergic medications, and eight age-matched control subjects. We scanned one tomographic level through the temporal lobes that included both temporal neocortex and mesial temporal cortex, and one tomographic level through the basal ganglia that included frontal and parietal cortex. Previously determined rate constants and an operational equation were used to determine rCMRglc. On average, rCMRglc values were 23% below control values for all regions studied, with the greatest differences in posterior brain regions (visual association cortex, primary visual cortex, and parietal cortex) and thalamus. These results indicate that PD patients may show neocortical hypometabolism, especially in posterior brain regions, in the absence of any demonstrable cognitive deficits. C1 UNIV CALIF DAVIS,DEPT NEUROL,DAVIS,CA 95616. RP EBERLING, JL (reprint author), LAWRENCE BERKELEY LAB,CTR FUNCT IMAGING,55-121,1 CYCLOTRON,BERKELEY,CA 94720, USA. FU NIA NIH HHS [AG07793, AG10129] NR 60 TC 68 Z9 72 U1 1 U2 3 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 SN 0197-4580 J9 NEUROBIOL AGING JI Neurobiol. Aging PD MAY-JUN PY 1994 VL 15 IS 3 BP 329 EP 335 DI 10.1016/0197-4580(94)90028-0 PG 7 WC Geriatrics & Gerontology; Neurosciences SC Geriatrics & Gerontology; Neurosciences & Neurology GA NQ033 UT WOS:A1994NQ03300006 PM 7936057 ER PT J AU ASHBY, CR ZHANG, JY EDWARDS, E WANG, RY AF ASHBY, CR ZHANG, JY EDWARDS, E WANG, RY TI THE INDUCTION OF SEROTONIN(3)-LIKE RECEPTOR SUPERSENSITIVITY AND DOPAMINE-RECEPTOR SUBSENSITIVITY IN THE RAT MEDIAL PREFRONTAL CORTEX AFTER THE INTRAVENTRICULAR ADMINISTRATION OF THE NEUROTOXIN 5,7-DIHYDROXYTRYPTAMINE - A MICROIONTOPHORETIC STUDY SO NEUROSCIENCE LA English DT Article ID DENERVATION SUPER-SENSITIVITY; ELECTROPHYSIOLOGICAL CHARACTERIZATION; SEROTONERGIC SYSTEM; RELEASE; NEURONS; SELECTIVITY; HIPPOCAMPUS; DERIVATIVES; ACTIVATION; HYDROLYSIS AB This study examines the effect of intraventricular administration of the neurotoxin 5,7-dihydroxytryptamine on serotonin(1A), serotonin(2) and serotonin(3) receptors in the rat medial prefrontal cortex using in vivo extracellular single cell recording and iontophoresis. Iontophoresis of the serotonin(1A), serotonin(1C,2) and serotonin(3) receptor agonists (+/-)-8-hydroxy-(di-n-propyl)aminotetralin, (+/-)-1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane and 2-methylserotonin, respectively, produces a current-dependent (5-80 nA) suppression of the basal firing rate of medial prefrontal cortical cells in sham- and 5,7-dihydroxytryptamine-lesioned rats. The suppression produced by 2-methylserotonin and serotonin was significantly greater in 5,7-dihydroxytryptamine-lesioned rats than in control rats. No significant difference in the spontaneous activity of medial prefrontal cortex cells was observed between experimental and control rats after iontophoresis of (+/-)-8-hydroxy-(di-n-propyl)aminotetralin or (+/-)-1(2,5-dimethoxy-4-iodophenyl)-2-aminopropane. There was no significant difference between the groups regarding the response of medial prefrontal cortex cells to the iontophoresis of GABA, whereas the response of medial prefrontal cortex cells to the iontophoresis of dopamine was significantly attenuated in animals pretreated with 5,7-dihydroxytryptamine compared to controls. Our results indicate that 5,7-dihydroxytryptamine-induced denervation selectively enhances the sensitivity of serotonin(3)-like receptors in the medial prefrontal cortex, which could, at least partially, account for the serotonin denervation supersensitivity. Moreover, the finding that the response of medial prefrontal cortical cells to the iontophoresis of dopamine is attenuated in 5,7-dihydroxytrptamine pretreated rats is consistent with the view that the inhibitory action of dopamine in the medial prefrontal cortex is dependent upon serotonin tone. C1 SUNY STONY BROOK,DEPT PSYCHIAT & BEHAV SCI,STONY BROOK,NY 11794. BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11794. UNIV MARYLAND,DEPT PHARMACOL & TOXICOL,BALTIMORE,MD 21100. FU NIDA NIH HHS [1 RO1 DA07193, 1 RO3 DA 0680072]; NIMH NIH HHS [R01 MH41440] NR 43 TC 20 Z9 21 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0306-4522 J9 NEUROSCIENCE JI Neuroscience PD MAY PY 1994 VL 60 IS 2 BP 453 EP 462 DI 10.1016/0306-4522(94)90256-9 PG 10 WC Neurosciences SC Neurosciences & Neurology GA NK708 UT WOS:A1994NK70800015 PM 8072691 ER PT J AU SHIRAI, H HIRAYAMA, T KOIDE, Y YOSHIDA, H NAITO, O SATO, M FUKUDA, T SUGIE, T AZUMI, M MIKKELSEN, DR SCOTT, SD GREK, B HILL, KW JOHNSON, DW MANSFIELD, DK PARK, HK STRATTON, BC SYNAKOWSKI, EJ TAYLOR, G TOWNER, HH AF SHIRAI, H HIRAYAMA, T KOIDE, Y YOSHIDA, H NAITO, O SATO, M FUKUDA, T SUGIE, T AZUMI, M MIKKELSEN, DR SCOTT, SD GREK, B HILL, KW JOHNSON, DW MANSFIELD, DK PARK, HK STRATTON, BC SYNAKOWSKI, EJ TAYLOR, G TOWNER, HH TI ION TEMPERATURE PROFILE SIMULATION OF JT-60 AND TFTR PLASMAS WITH ION TEMPERATURE-GRADIENT MODE TRANSPORT MODELS SO NUCLEAR FUSION LA English DT Article ID FUSION TEST REACTOR; EXCHANGE RECOMBINATION SPECTROSCOPY; TOKAMAK TRANSPORT; DRIVEN TURBULENCE; DRIFT INSTABILITIES; ENERGY CONFINEMENT; TOROIDAL ROTATION; ELECTRON; HEAT; CODE AB Ion temperature profiles of neutral beam heated plasmas in JT-60 and TFTR have been simulated using models of ion thermal diffusivity, chi(i), based on ion temperature gradient mode (eta(i) mode) turbulence and drift wave turbulence (trapped electron mode and circulating electron mode). The ion temperature profiles measured by charge exchange recombination spectroscopy are compared to predicted T(i) profiles calculated from three theoretical models for ion heat transport by Dominguez and Waltz, Lee and Diamond, and Romanelli. All three chi(i) models can reproduce the measured T(i) profile over a wide range of parameters in JT-60 L mode plasmas, except for two 1 MA limiter cases. With the use of transport models, which were adjusted to fit JT-60 plasmas, it was found that the Dominguez and Waltz and Romanelli models agree with measured T(i) profiles in TFTR L mode discharges in the region a/4 < r < a/2. The observed central peaking of T(i) near the magnetic axis of TFTR L mode plasmas cannot be reproduced. It was found that the Lee and Diamond model does not fit the data as well. The chi(i) models studied cannot consistently reproduce the measured T(i) in the peripheral region of either JT-60 or TFTR plasmas. In the high ion temperature (high T(i)) plasmas of JT-60 and supershot plasmas of TFTR, the predicted T(i) profiles are much broader than the measured profile. In supershot plasmas, the measured central ion temperature greatly exceeds the predicted temperature, although there is reasonable agreement near the edge. C1 PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08544. RP SHIRAI, H (reprint author), JAPAN ATOM ENERGY RES INST,NAKA FUS RES ESTAB,DEPT FUS PLASMA RES,NAKA,IBARAKI,JAPAN. NR 68 TC 7 Z9 7 U1 0 U2 0 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 1994 VL 34 IS 5 BP 703 EP 727 DI 10.1088/0029-5515/34/5/I09 PG 25 WC Physics, Fluids & Plasmas SC Physics GA NX960 UT WOS:A1994NX96000009 ER PT J AU STRATTON, BC FONCK, RJ MCKEE, G THORSON, T HAMMETT, GW PHILLIPS, CK SYNAKOWSKI, EJ AF STRATTON, BC FONCK, RJ MCKEE, G THORSON, T HAMMETT, GW PHILLIPS, CK SYNAKOWSKI, EJ TI SPECTROSCOPIC OBSERVATION OF O-300 KEV HE-3 IONS PRODUCED BY ICRF HEATING IN TFTR SO NUCLEAR FUSION LA English DT Letter ID ALPHA-CHERS RP STRATTON, BC (reprint author), PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08544, USA. RI Hammett, Gregory/D-1365-2011 OI Hammett, Gregory/0000-0003-1495-6647 NR 11 TC 5 Z9 5 U1 0 U2 0 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD MAY PY 1994 VL 34 IS 5 BP 734 EP 739 DI 10.1088/0029-5515/34/5/I02 PG 6 WC Physics, Fluids & Plasmas SC Physics GA NX960 UT WOS:A1994NX96000011 ER PT J AU FRIEDMAN, A BOZOKI, E AF FRIEDMAN, A BOZOKI, E TI USE OF EIGENVECTORS IN UNDERSTANDING AND CORRECTING STORAGE-RING ORBITS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB The response matrix A is defined by the equation X = ATHETA, where THETA is the kick vector and X is the resulting orbit vector. Since A is not necessarily a symmetric or even a square matrix we symmetrize it by using A(T)A. Then we find the eigenvalues and eigenvectors of this A(T)A matrix. The physical interpretation of the eigenvectors for circular machines is discussed. The task of the orbit correction is to find the kick vector THETA for a given measured orbit vector X. We are presenting a method, in which the kick vector is expressed as linear combination of the eigenvectors. An additional advantage of this method is that it yields the smallest possible kick vector to correct the orbit. We will illustrate the application of the method to the NSLS X-ray and UV storage rings and the resulting measurements. It will be evident, that the accuracy of this method allows the combination of the global orbit correction and local optimization of the orbit for beam lines and insertion devices. The eigenvector decomposition can also be used for optimizing kick vectors, taking advantage of the fact that eigenvectors with corresponding small eigenvalues generate negligible orbit changes. Thus, one can reduce a kick vector calculated by any other correction method and still stay within the tolerance for orbit correction. The use of eigenvectors in accurately measuring the response matrix and the use of the eigenvalue decomposition orbit correction algorithm in digital feedback is discussed. RP FRIEDMAN, A (reprint author), BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973, USA. NR 19 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1994 VL 344 IS 2 BP 269 EP 277 DI 10.1016/0168-9002(94)90075-2 PG 9 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NJ929 UT WOS:A1994NJ92900003 ER PT J AU FERGUSON, PD SOMMER, WF MUELLER, GE BORDEN, MJ AF FERGUSON, PD SOMMER, WF MUELLER, GE BORDEN, MJ TI A THERMOCOUPLE-BASED BEAM PROFILE MONITOR FOR AN 800 MEV PROTON ACCELERATOR SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB A thermocouple-based proton beam profile monitor is designed for use in front of the Los Alamos Neutron Scattering Center target. The purpose of the device is to determine the location and standard deviation of the incident proton beam using thermocouple temperatures. The beam profile monitor consists of two perpendicular planes of thermocouple wires mounted in 1 cm increments on Macor ceramic rings. Temperatures are measured from heat generated volumetrically in the thermocouple wires by the incident proton beam. Operating requirements for the device include the ability to work in pressure ranges of 0.1 to 10 Torr and at beam currents of 5 muA to 100 muA. Temperature data from a beam test are compared with predictions from an analytical model, a finite elements analysis using, the code TOPAZ2D, and an automated curve fitting routine. Average relative errors of less than 10% are calculated from the analytical solution and the finite elements analysis. The curve fitting routine provides quick estimates of the proton beam parameters which are useful during beam tuning. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. RP FERGUSON, PD (reprint author), UNIV MISSOURI,ROLLA,MO 65401, USA. OI Mueller, Gary/0000-0001-5963-9026; Ferguson, Phillip/0000-0002-7661-4223 NR 14 TC 0 Z9 0 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1994 VL 344 IS 2 BP 300 EP 306 DI 10.1016/0168-9002(94)90078-7 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NJ929 UT WOS:A1994NJ92900006 ER PT J AU BENARY, O CLELAND, W FERGUSON, I GORDEEV, A GORDON, H KISTENEV, E KROON, P LELTCHOUK, M LISSAUER, D MA, H MAKOWIECKI, D MASLENNIKOV, A MCCORKLE, S ONOPRIENKO, D ONUCHIN, A OREN, Y PANIN, V PARSONS, JA RADEKA, V ROGERS, L RAHM, D RESCIA, S RUTHERFOORD, J SEMAN, M SMITH, M SONDERICKER, J STEINER, R STEPHANI, D STERN, E STUMER, I TAKAI, H THEMANN, H TIKHONOV, Y WILLIS, WJ AF BENARY, O CLELAND, W FERGUSON, I GORDEEV, A GORDON, H KISTENEV, E KROON, P LELTCHOUK, M LISSAUER, D MA, H MAKOWIECKI, D MASLENNIKOV, A MCCORKLE, S ONOPRIENKO, D ONUCHIN, A OREN, Y PANIN, V PARSONS, JA RADEKA, V ROGERS, L RAHM, D RESCIA, S RUTHERFOORD, J SEMAN, M SMITH, M SONDERICKER, J STEINER, R STEPHANI, D STERN, E STUMER, I TAKAI, H THEMANN, H TIKHONOV, Y WILLIS, WJ TI PERFORMANCE OF AN ACCORDION ELECTROMAGNETIC CALORIMETER WITH LIQUID KRYPTON AND ARGON SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article ID ION-PAIR AB Test results of a liquid krypton/argon electromagnetic calorimeter with accordion type electrode structure are presented. The test was carried out at the Brookhaven AGS in a negative beam with good electron identification at momenta 5, 10, 15, and 20 GeV/c. Results on energy resolution, linearity, pointing resolution, and muon response are presented. The results are in good agreement with Monte Carlo calculations. The energy resolution of 6.7%/square-root E was achieved using liquid krypton and 7.7%/square-root E with liquid argon, with a negligible constant term. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV ARIZONA,TUCSON,AZ 85722. BUDKER NUCL PHYS INST,NOVOSIBIRSK,RUSSIA. COLUMBIA UNIV,NEVIS LABS,IRVINGTON,NY 10533. ADELPHI UNIV,GARDEN CITY,NY 11530. UNIV PITTSBURGH,PITTSBURGH,PA 15260. SUNY STONY BROOK,STONY BROOK,NY 11794. OAK RIDGE NATL LAB,OAK RIDGE,TN 37830. TEL AVIV UNIV,IL-69978 TEL AVIV,ISRAEL. RI Rescia, Sergio/D-8604-2011; Takai, Helio/C-3301-2012 OI Rescia, Sergio/0000-0003-2411-8903; Takai, Helio/0000-0001-9253-8307 NR 24 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1994 VL 344 IS 2 BP 363 EP 377 DI 10.1016/0168-9002(94)90085-X PG 15 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NJ929 UT WOS:A1994NJ92900013 ER PT J AU BOZOKI, E SAGAN, D AF BOZOKI, E SAGAN, D TI ON THE SHAKING OF IONS IN ELECTRON STORAGE-RINGS (VOL 340, PG 259, 1994) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Correction, Addition C1 CORNELL UNIV,NUCL STUDIES LAB,ITHACA,NY 14853. RP BOZOKI, E (reprint author), BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1994 VL 344 IS 2 BP 438 EP 438 DI 10.1016/0168-9002(94)90096-5 PG 1 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NJ929 UT WOS:A1994NJ92900024 ER PT J AU TATCHYN, R AF TATCHYN, R TI SIMPLE APPROXIMATIONS TO TRANSVERSE WIGGLER SPECTRA INTEGRATED OVER FINITE APERTURES IN THE WIGGLE PLANE (VOL 336, PG 361, 1993) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Correction, Addition RP TATCHYN, R (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94305, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1994 VL 344 IS 2 BP 439 EP 439 DI 10.1016/0168-9002(94)90097-3 PG 1 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NJ929 UT WOS:A1994NJ92900025 ER PT J AU SMITH, DL AF SMITH, DL TI COVARIANCE ANALYSIS AND FITTING OF GERMANIUM GAMMA-RAY DETECTOR EFFICIENCY CALIBRATION DATA (VOL 290, PG 499, 1990) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Correction, Addition RP SMITH, DL (reprint author), ARGONNE NATL LAB,DEPT TECHNOL DEV,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAY 1 PY 1994 VL 344 IS 2 BP 440 EP 440 DI 10.1016/0168-9002(94)90098-1 PG 1 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NJ929 UT WOS:A1994NJ92900026 ER PT J AU FUNSTEN, HO BARRACLOUGH, BL MCCOMAS, DJ AF FUNSTEN, HO BARRACLOUGH, BL MCCOMAS, DJ TI INTERACTIONS OF SLOW H, H-2, AND H-3 WITH THIN CARBON FOILS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID FAST MOLECULAR-IONS; MULTIPLE-SCATTERING; SOLIDS AB Interaction processes resulting from the transit of incident 2-30 keV H+, H-2+ and H-3+ through 1.2 to 2.5 mug cm-2 carbon foils are investigated by examining the charge state and angular scatter distributions Of atomic and molecular species that exit the foils. A comparison of the scatter distributions of exiting H-2+ and H-0 from incident H-2+ and H-3+ show that the atomic components of transmitted molecules scatter independently from foil atoms. For a given foil thickness, the measured fractions of H-2+ from incident H-2+ and H-3+ are inversely proportional to the square of the angular scatter half-width. RP FUNSTEN, HO (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Funsten, Herbert/A-5702-2015 OI Funsten, Herbert/0000-0002-6817-1039 NR 20 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 24 EP 28 DI 10.1016/0168-583X(94)95503-4 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600005 ER PT J AU BAUBLIS, VV CARRIGAN, RA CHEN, D COOPER, PS DANIELS, DC KHANZADEEV, AV LACH, J MORELOS, A SAMSONOV, VM SMITH, VJ STRIKHANOV, MN SUN, CR TERENTYEV, NK TIMM, S VOROBYOV, AA AF BAUBLIS, VV CARRIGAN, RA CHEN, D COOPER, PS DANIELS, DC KHANZADEEV, AV LACH, J MORELOS, A SAMSONOV, VM SMITH, VJ STRIKHANOV, MN SUN, CR TERENTYEV, NK TIMM, S VOROBYOV, AA TI MEASURING THE MAGNETIC-MOMENTS OF SHORT-LIVED PARTICLES USING CHANNELING IN BENT CRYSTALS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID CHARMED BARYONS; ASYMMETRY PARAMETER; LAMBDA-C+; SIGMA+; DECAY; HADROPRODUCTION; POLARIZATION; QUARKONIUM; HYPERON; MODEL AB A recent demonstration of spin precession using channeling in a bent crystal offers the interesting possibility of a technique to measure magnetic moments of short-lived charm baryons, There are significant differences among theoretical models of these moments. Accumulating experimental evidence indicates the tools used for hyperon magnetic moment measurements, polarized production and decay asymmetries, may also be available with heavier baryons. Useful measurements may be possible using the channeling technique but they will require challenging beam conditions. C1 MOSCOW ENGN PHYS INST,MOSCOW 115409,RUSSIA. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. UNIV BRISTOL,HH WILLS PHYS LAB,BRISTOL BS8 1TL,AVON,ENGLAND. SUNY ALBANY,ALBANY,NY 12222. CARNEGIE MELLON UNIV,PITTSBURGH,PA 15213. RP BAUBLIS, VV (reprint author), PETERSBURG NUCL PHYS INST,GATCHINA,RUSSIA. RI Strikhanov, Mikhail/P-7393-2014 OI Strikhanov, Mikhail/0000-0003-2586-0405 NR 36 TC 9 Z9 9 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 112 EP 118 DI 10.1016/0168-583X(94)95524-7 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600026 ER PT J AU BAKER, SI CARRIGAN, RA CUPPS, VR FORSTER, JS GIBSON, WM SUN, CR AF BAKER, SI CARRIGAN, RA CUPPS, VR FORSTER, JS GIBSON, WM SUN, CR TI EFFECTS ON CHANNELING OF RADIATION-DAMAGE DUE TO 28 GEV PROTONS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID BEAM; EXTRACTION; CRYSTAL AB For an irradiation of 2.9 x 10(19) protons at a beam energy of 28 GeV, the channeling minimum yield in a silicon single crystal increased from 2.3% to 4.1%. The radiation damage occurred with a proton fluence of (4.1 +/- 1.4) x 10(20)/cm2. The degradation was measured with MeV-range He ions using Rutherford backscattering. The relevance to bent crystal extraction of TeV beams is discussed. C1 FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. SUPERCOND SUPER COLLIDER LAB,DALLAS,TX 75237. AECL RES,CHALK RIVER LABS,CHALK RIVER K0J 1J0,ON,CANADA. SUNY ALBANY,ALBANY,NY 12222. NR 17 TC 14 Z9 14 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 119 EP 123 DI 10.1016/0168-583X(94)95525-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600027 ER PT J AU CARRIGAN, RA CHEN, D COLESTOCK, P HERRUP, D GODERRE, G JACKSON, G MURPHY, CT STEFANSKI, R BAKER, S MOKHOV, N PARKER, B SHIH, HJ SOUNDRANAYAGAM, R TOOHIG, T PEGGS, S SUN, CR BODEN, A CLINE, D GABELLA, W RAMACHANDRAN, S RHOADES, J ROSENZWEIG, J ARENTON, M CONETTI, S COX, B DUKES, C GOLOVATYUK, V MCMANUS, A NELSON, K NOREM, B NEWBERGER, B ELLISON, JA ERWIN, A ROSSMANITH, R KOVALENKO, A TARATIN, A MALAKHOV, N TSYGANOV, E BAVIZHEV, M BIRYUKOV, V MASLOV, M KHANZADEEV, A PROKOFIEVA, T SAMSONOV, V SOLODOV, G AF CARRIGAN, RA CHEN, D COLESTOCK, P HERRUP, D GODERRE, G JACKSON, G MURPHY, CT STEFANSKI, R BAKER, S MOKHOV, N PARKER, B SHIH, HJ SOUNDRANAYAGAM, R TOOHIG, T PEGGS, S SUN, CR BODEN, A CLINE, D GABELLA, W RAMACHANDRAN, S RHOADES, J ROSENZWEIG, J ARENTON, M CONETTI, S COX, B DUKES, C GOLOVATYUK, V MCMANUS, A NELSON, K NOREM, B NEWBERGER, B ELLISON, JA ERWIN, A ROSSMANITH, R KOVALENKO, A TARATIN, A MALAKHOV, N TSYGANOV, E BAVIZHEV, M BIRYUKOV, V MASLOV, M KHANZADEEV, A PROKOFIEVA, T SAMSONOV, V SOLODOV, G TI EXTRACTION FROM TEV-RANGE ACCELERATORS USING BENT CRYSTAL CHANNELING SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID PROTON AB Plans and first results from Fermilab Experiment 853 are presented. E853 is an experiment to test the feasibility and efficiency of extracting a low-intensity beam from the halo of the Tevatron using channeling in a bent silicon crystal. The motivation of the experiment is to apply crystal extraction to trans-TeV accelerators like the LHC. Channeling developments related to crystal extraction and some early results from accelerator studies at the Tevatron are presented. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. SUPERCOND SUPER COLLIDER LAB,DALLAS,TX 75237. UNIV NEW MEXICO,ALBUQUERQUE,NM 87131. SUNY ALBANY,ALBANY,NY 12222. UNIV CALIF LOS ANGELES,LOS ANGELES,CA 90024. UNIV VIRGINIA,CHARLOTTESVILLE,VA 22903. UNIV TEXAS,AUSTIN,TX 78712. UNIV WISCONSIN,MADISON,WI 53706. CEBAF,NEWPORT NEWS,VA 23606. JOINT INST NUCL RES,DUBNA,RUSSIA. SERPUKHOV HIGH ENERGY PHYS INST,SERPUKHOV,RUSSIA. PETERSBURG NUCL PHYS INST,GATCHINA,RUSSIA. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. RP CARRIGAN, RA (reprint author), FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510, USA. RI Biryukov, Valery/C-8432-2017 OI Biryukov, Valery/0000-0002-3591-7762 NR 23 TC 17 Z9 17 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 128 EP 132 DI 10.1016/0168-583X(94)95527-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600029 ER PT J AU BAUBLIS, VV IVANOV, IV IVOCHKIN, IG KHANZADEEV, AV KURYATKOV, VV LAPIN, E MIFTAKHOV, NM MOROZOV, VF NOVIKOV, SR PROKOFIEVA, TJ SAMSONOV, VM SOLODOV, G DVORNIKOV, BD LOGINOV, BB KOLESON, YE KOCHENOVA, AA CARRIGAN, RA CHEN, D STRIKHANOV, MN AF BAUBLIS, VV IVANOV, IV IVOCHKIN, IG KHANZADEEV, AV KURYATKOV, VV LAPIN, E MIFTAKHOV, NM MOROZOV, VF NOVIKOV, SR PROKOFIEVA, TJ SAMSONOV, VM SOLODOV, G DVORNIKOV, BD LOGINOV, BB KOLESON, YE KOCHENOVA, AA CARRIGAN, RA CHEN, D STRIKHANOV, MN TI APPARATUS FOR MAGNETIC-MOMENT MEASUREMENT USING CHANNELING IN BENT CRYSTALS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO AB A recent experiment has demonstrated spin precession using a bent channeling crystal. In the experiment defect dechanneling was studied and dechanneling from dislocation slip planes was observed for the first time. Information was gained on preparing the crystal detectors. X-ray diffraction techniques were developed for pre-alignment. Ramifications for trans-TeV channeling are explored. C1 PETERSBURG NUCL PHYS INST,GATCHINA,RUSSIA. SRI ELECTRON,ST PETERSBURG,RUSSIA. MOSCOW ENGN PHYS INST,MOSCOW 115409,RUSSIA. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. RI Strikhanov, Mikhail/P-7393-2014 OI Strikhanov, Mikhail/0000-0003-2586-0405 NR 11 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 150 EP 155 DI 10.1016/0168-583X(94)95531-X PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600033 ER PT J AU BRIERE, MA SCHNEIDER, D MCDONALD, J REAVES, M RUHLICKE, C WEINBERG, G KNAPP, D AF BRIERE, MA SCHNEIDER, D MCDONALD, J REAVES, M RUHLICKE, C WEINBERG, G KNAPP, D TI STUDIES OF THE INTERACTION OF SLOW VERY HIGHLY-CHARGED IONS WITH SOLID-SURFACES USING THE LLNL EBIT FACILITY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID ELECTRON-EMISSION; HOLLOW ATOMS; ABOVE-SURFACE; METAL-SURFACE; NEUTRALIZATION; AUGER; TRAP AB A summary of the present status of the LLNL EBIT based research program on highly charged ion-solid surface interaction is presented. New results for coincidence measurements of K(alpha)-K(beta) X-ray emission for Fe26+ incident on Al, using two Ge detectors are presented. It is shown that excellent resolution of the satellite and hypersatellite lines are achieved, in excess of what is possible with single Ge detector measurements. Recent results from ongoing investigations on electron emission, sputtered ion and energy loss phenomena are presented. Results from charge-state analysis of grazing incidence specular scattering of highly charged ions off atomically flat surfaces of gold, carbon and mica indicate that the incident ion essentially reaches ground state of its electronic distribution within the ion-surface interaction time of approximately 100 fs. Atomic force microscopy is used to investigate the formation of a new type of ion induced surface defect, peculiar to highly charged ion-surface interactions. A linear correlation, between the defect volume and the incident ion charge, supports a mechanism of defect formation due to potential energy induced electron emission and subsequent collective displacement due to local charge imbalance. RP BRIERE, MA (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV HIGH TEMP PHYS,LIVERMORE,CA 94550, USA. NR 31 TC 16 Z9 16 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 231 EP 236 DI 10.1016/0168-583X(94)95546-8 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600048 ER PT J AU OVERBURY, SH AF OVERBURY, SH TI COMPARISON OF EXPERIMENTAL AND SIMULATED LOW-ENERGY ALKALI ION-SCATTERING SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID SURFACE; SEGREGATION; MO(001); OXYGEN; LI+ AB Computer simulations performed using the MARLOWE code are compared with experimental results obtained for 1 keV Li+ ion scattering from W(001). Trajectory analysis using distributions of impact points, deflections and maximum penetration depths allow characterization of the contributing scattering mechanisms. Computer simulation is found to reproduce many of the observed features in the energy distributions and in the incident angle dependence, but there are also important differences. In agreement with experiment, a sharp, surface sensitive binary collision peak is found at certain angles but at others this peak may broaden, shift to lower energy and grow in intensity due to subsurface scattering mechanisms. Simulations overestimate the relative scattering intensity near critical edges and the importance of focused scattering from second layer atoms. RP OVERBURY, SH (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37830, USA. RI Overbury, Steven/C-5108-2016 OI Overbury, Steven/0000-0002-5137-3961 NR 11 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 286 EP 290 DI 10.1016/0168-583X(94)95558-1 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600060 ER PT J AU ALEXANDER, DE FULLERTON, EE BALDO, PM SOWERS, CH REHN, LE AF ALEXANDER, DE FULLERTON, EE BALDO, PM SOWERS, CH REHN, LE TI NEUTRON-INDUCED COLLISION CASCADE MIXING IN NB/V SUPERLATTICES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID IONS AB High-angle X-ray diffraction was used to determine cascade mixing efficiencies, Dt/dpa, in Nb/V superlattices irradiated to small doses (less-than-or-equal-to 0.26 dpa). Samples were neutron irradiated in the core of the High Flux Beam Reactor at Brookhaven National Laboratory and ion irradiated with 1.5 MeV Ne. No significant differences were observed in cascade mixing efficiencies between the two types of irradiation. Values of Dt/dpa were observed to vary with the modulation wavelength of the superlattice, with thicker wavelength samples yielding values approaching that determined from ion mixing thick Nb/V bilayers (Dt/dpa almost-equal-to 110 angstrom2/dpa). The decrease in mixing efficiency observed at lower wavelengths may be related to an observed structural transition in which the interfaces of the superlattice become coherent. RP ALEXANDER, DE (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. RI Fullerton, Eric/H-8445-2013 OI Fullerton, Eric/0000-0002-4725-9509 NR 20 TC 2 Z9 2 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 344 EP 348 DI 10.1016/0168-583X(94)95568-9 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600070 ER PT J AU PITARKE, JM RITCHIE, RH AF PITARKE, JM RITCHIE, RH TI DOUBLE PLASMON EXCITATION IN AN ELECTRON-GAS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID Z(1)(3) CORRECTION; ALUMINUM; SPECTROSCOPY AB A many-body perturbation-theoretic calculation of the double-plasmon excitation in an electron ps is presented, using Feynman diagrams. The low-q limit of the inverse mean free path for this second order process is evaluated in the random-phase-approximation, and it is compared to previous theoretical and experimental estimations. C1 OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. RP PITARKE, JM (reprint author), EUSKAL HERRIKO UNIBERTSITATEA, ZIENTZI FALKULTATEA, MATERIA KONDENTSATUAREN FIS SAILA, E-48080 BILBAO, SPAIN. RI Pitarke, Jose/C-8602-2009 OI Pitarke, Jose/0000-0002-8253-8028 NR 16 TC 13 Z9 13 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 358 EP 362 DI 10.1016/0168-583X(94)95571-9 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600073 ER PT J AU GHOSH, VJ MCKEOWN, M WELCH, DO LYNN, KG AF GHOSH, VJ MCKEOWN, M WELCH, DO LYNN, KG TI AN AB-INITIO MONTE-CARLO STUDY OF LOW-ENERGY POSITRON AND ELECTRON IMPLANTATION IN ELEMENTAL METALS AND MULTILAYERS SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID SOLIDS AB A Monte Carlo code developed at Brookhaven to study positron and electron implantation in solids will be discussed. This code models the trajectories of a large number of positrons or electrons as they move through the material and uses this information to calculate stopping profiles, backscattered fractions and transmitted fractions. The particle-atom interactions are incorporated via elastic and inelastic scattering cross-sections. The incident particle energies vary from 1 to 10 keV and the simulation stops when the particle energy goes down to 25 eV or if the particle is backscattered. Main results of our Monte Carlo simulations of the mean implantation depth and implantation profiles for both semi-infinite metallic elements and multilayers will be discussed. RP GHOSH, VJ (reprint author), BROOKHAVEN NATL LAB, DEPT APPL SCI, UPTON, NY 11973 USA. NR 24 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 442 EP 445 DI 10.1016/0168-583X(94)95590-5 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600092 ER PT J AU ROBINSON, MT AF ROBINSON, MT TI THE STATISTICS OF SPUTTERING SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID COMPUTER-SIMULATION; COLLISION CASCADES; SOLIDS AB The MARLOWE program was used to study the statistics of sputtering, on the example of 1 to 100 keV Au atoms normally incident on static (001) and (111) Au crystals. The yield of sputtered atoms was examined as a function of the impact point of the incident particles (''ions'') on the target surfaces. There were variations on two scales. The effects of the axial and planar channeling of the ions could be traced, the details depending on the orientation of the target and the energies of the ions. Locally, the sputtering yield was very sensitive to the impact point, small changes in position often producing large changes in yield. The results indicate strongly that the sputtering yield is a random (''chaotic'') function of the impact point. RP ROBINSON, MT (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,POB 2008,OAK RIDGE,TN 37831, USA. NR 15 TC 10 Z9 10 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 509 EP 512 DI 10.1016/0168-583X(94)95604-9 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600106 ER PT J AU COON, SR CALAWAY, WF PELLIN, MJ AF COON, SR CALAWAY, WF PELLIN, MJ TI NEUTRAL COPPER CLUSTER SPUTTERING YIELDS - NE+, AR+ AND XE+ BOMBARDMENT SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID KINETIC-ENERGY DISTRIBUTIONS; RESONANCE IONIZATION; MULTIPHOTON IONIZATION; MASS-DISTRIBUTION; ION-BOMBARDMENT; METAL-SURFACES AB The sputtering of neutral metal clusters was investigated by measuring relative sputtering yields of copper clusters ejected from polycrystalline copper under 3.9 keV bombardment by Ne+, Ar+ and Xe+ ions at normal incidence. The yields of clusters from Ne+ bombardment were lower than those from Ar+ bombardment, and yields from Ar+ bombardment were lower than those from Xe+ bombardment. The sputtering yield ratios Ne+/Ar+ and Xe+/Ar+ were measured to be 0.56 and 1.08. The size distribution of the sputtered clusters can be fit by a power law dependence with exponents of -8.1, -8.2 and -6.2 for Ne+, Ar+ and Xe+, respectively. The similarity of the exponents of the Ne+ and Ar+ power law fits indicates that the sputtering yields for these two primary ions are similar, while that for Xe+ is substantially higher, in contrast to the sputtering yield ratio data. The difference between the two measurements can be explained by assuming a systematic uncertainty in the sputtering yield ratio measurements that makes the measured ratios lower than the true values. Assuming a value at the high end of the experimental Ne+ sputtering yield range, the exponents of the power law fits exhibit a linear dependence on the total sputtering yield. C1 ARGONNE NATL LAB,DIV CHEM TECHNOL,ARGONNE,IL 60439. ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. RI Pellin, Michael/B-5897-2008 OI Pellin, Michael/0000-0002-8149-9768 NR 23 TC 38 Z9 38 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 518 EP 522 DI 10.1016/0168-583X(94)95606-5 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600108 ER PT J AU ANTOLAK, AJ BENCH, GS AF ANTOLAK, AJ BENCH, GS TI PIXEF - THE LIVERMORE PIXE SPECTRUM ANALYSIS PACKAGE SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 15th International Conference on Atomic Collisions in Solids (ICACS-15) CY JUL 26-30, 1993 CL UNIV W ONTARIO, LONDON, CANADA HO UNIV W ONTARIO ID QUANTITATIVE-ANALYSIS; SHELL; PROTON; YIELDS AB PIXEF (for PIXE-fit) is a proton-induced X-ray emission (PIXE) data analysis program designed for analyzing medium to heavy element matrices while retaining the capability to treat lower atomic number targets. Using nonlinear least squares fitting techniques, algorithms have been developed or modified for both fitting the characteristic X-ray peaks and representing the associated bremsstrahlung and gamma-ray background. Self-absorption and secondary fluorescence are explicitly determined for K-shell and L-subshell X-rays. Data bases have been created or improved, where necessary, from reliable current literature values or by direct measurement for element mass attenuation coefficients, photoionization and proton ionization cross sections, Coster-Kronig transition probabilities, fluorescence yields, and relative line intensities. The utility of the program is demonstrated with PIXE spectra obtained at Livermore. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP ANTOLAK, AJ (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. NR 21 TC 31 Z9 31 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 90 IS 1-4 BP 596 EP 601 DI 10.1016/0168-583X(94)95620-0 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NM766 UT WOS:A1994NM76600122 ER PT J AU EINFELD, D BUTTIG, H DIENEL, S GLASER, W GOETZ, T GURATZSCH, H HARTMANN, B JANSSEN, D KRUG, H LINNEMANN, J MATZ, W MURPHY, JB NEUMANN, W OEHME, W PICARD, M PLESKO, M PROHL, D SCHLENK, R TOMASSINI, D TYRROFF, H AF EINFELD, D BUTTIG, H DIENEL, S GLASER, W GOETZ, T GURATZSCH, H HARTMANN, B JANSSEN, D KRUG, H LINNEMANN, J MATZ, W MURPHY, JB NEUMANN, W OEHME, W PICARD, M PLESKO, M PROHL, D SCHLENK, R TOMASSINI, D TYRROFF, H TI THE SYNCHROTRON LIGHT-SOURCE ROSY SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article AB ROSY, a 3rd generation synchrotron light source, has been proposed to be built at the Research Center Rossendorf/Dresden in Germany. With its low emittance and optimized space for installing insertion devices ROSY will be the first synchrotron radiation source in the 3 GeV range in Europe, dedicated to materials research and industrial application. The critical wavelength of the synchrotron radiation spectra was designed to be 0.15 nm corresponding to a critical photon energy of 8.4 keV. It is proposed to use a ''modified multiple bend achromat'' (MBA) lattice in order to get a compact machine as well as a low emittance. For 3 GeV an emittance smaller than 30 pi nm rad can be obtained. With a fourfold symmetry and two larger straight sections within the achromatic arcs the circumference is 148 m. 23% of the circumference can be used for installing insertion devices. C1 NSLS BROOKHAVEN, UPTON, NY USA. UNIV BONN, W-5300 BONN, GERMANY. SINCROTRONE TRIESTE, TRIESTE, ITALY. RP EINFELD, D (reprint author), RES CTR ROSSENDORF INC, POB 510119, D-01314 DRESDEN, GERMANY. NR 11 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 89 IS 1-4 BP 74 EP 78 DI 10.1016/0168-583X(94)95149-7 PG 5 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NL001 UT WOS:A1994NL00100017 ER PT J AU BENCH, GS LEFEVRE, HW LEGGE, GJF AF BENCH, GS LEFEVRE, HW LEGGE, GJF TI ION-BEAM-INDUCED CHANGES IN DROSOPHILA-MELANOGASTER BRAINS STUDIED WITH STIM SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID MICROANALYSIS; MICROPROBE; MASS AB Scanning transmission ion microscopy (STIM) with energy loss contrast has been used to study the effect of ion microbeam irradiation on semi-thick animal tissue specimens. Excised, freeze substituted Drosophila melanogaster brains have been scanned with a 3 MeV proton beam of current 150 pA focused to a spot size of 5 mum for exposures between 0.15 and 2.22 mC/cm2. Sample mass loss, volume loss and specimen deformation resulting from these irradiations have been observed with STIM using a 3 MeV proton beam current of approximately 2000 ions/focused to a spot size of approximately 0.5 mum. The similarity of the sample mass loss and volume loss curves suggests that volume losses are directly linked with the same beam specimen interactions that give rise to mass loss. C1 UNIV OREGON,DEPT PHYS,EUGENE,OR 97403. UNIV MELBOURNE,MICRO ANALYT RES CTR,SCH PHYS,PARKVILLE,VIC 3052,AUSTRALIA. RP BENCH, GS (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 17 TC 1 Z9 1 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 88 IS 3 BP 229 EP 236 DI 10.1016/0168-583X(94)95317-1 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NL987 UT WOS:A1994NL98700006 ER PT J AU GLIKMAN, E KELSON, I DOAN, NV TRUCHOT, P PICCOT, D PINTE, G HAUSTEIN, PE AF GLIKMAN, E KELSON, I DOAN, NV TRUCHOT, P PICCOT, D PINTE, G HAUSTEIN, PE TI ELEMENTAL AND ISOTOPIC EFFECTS IN NEUTRON-INDUCED DESORPTION FROM SURFACES SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article AB Recoil of atoms following (n, gamma) reactions may cause them to desorb from the surface. This effect is studied in irradiation experiments under high thermal neutron flux for gold and iridium, utilizing prepackaged ampules under vacuum. The role of thermal desorption is demonstrated, through a comparative study of the behavior of different elements under identical conditions. Precise measurements of the populations of iridium isotopes were carried out, revealing large Ir-194/Ir-192 differentiation. This is shown to be related to the temporal history of desorption during the irradiation, and provides additional meaningful information about the process. C1 TEL AVIV UNIV,RAYMOND & BEVERLY SACKLER FAC EXACT SCI,SCH PHYS & ASTRON,IL-52621 TEL HASHOMER,ISRAEL. CENS,CEREM,DTM,SRMP,F-91191 GIF SUR YVETTE,FRANCE. CENS,PIERRE SUE LAB,F-91191 GIF SUR YVETTE,FRANCE. BROOKHAVEN NATL LAB,DEPT CHEM,UPTON,NY 11973. NR 7 TC 0 Z9 0 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 88 IS 3 BP 237 EP 243 DI 10.1016/0168-583X(94)95318-X PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NL987 UT WOS:A1994NL98700007 ER PT J AU ANTOLAK, AJ BENCH, GS AF ANTOLAK, AJ BENCH, GS TI PIXE TOMOGRAPHY OF SAMPLES WITH INHOMOGENEOUS ELEMENTAL COMPOSITION SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID MICROTOMOGRAPHY; YIELDS; SHELL AB Proton induced X-ray emission tomography (PIXET) can provide quantitative, three-dimensional maps of elemental composition in small (less than a few mm) samples with fine (in principle micron scale) spatial resolution. The concept of PIXET is similar to single photon emission tomography which produces cross-sectional concentration maps of photon emitting radioactive elements within a sample. In PIXET, the photon emitting ''sources'' are elements along the trajectories (rays) of the incident beam as it slows down in the sample. The number of X-rays detected from a particular element at a given location in a sample depends on the local proton energy dependent X-ray production cross-section and the attenuation of the X-rays from that location to the detector. X-ray mass attenuation coefficients and proton stopping powers are weighted by the local elemental fractions along the detected X-ray path or incident beam direction. Local areal densities needed to complete the calculation of ion energy loss or X-ray attenuation are determined using the complementary density map obtained from ion microtomography (IMT) data. A software package is described which reconstructs cross-sectional images of density and element concentration of data obtained from samples having inhomogeneous elemental composition. A code has also been developed which generates simulated IMT and PIXET sinograms from user-specified density and composition maps of test objects. Simulated data from test objects having inhomogeneous elemental composition have been used to study the quality of images produced by the reconstruction code. Limitations of the PIXET technique are addressed. PIXET and IMT reconstructions from measured experimental data are discussed. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP ANTOLAK, AJ (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. NR 15 TC 14 Z9 14 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 88 IS 3 BP 297 EP 307 DI 10.1016/0168-583X(94)95328-7 PG 11 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NL987 UT WOS:A1994NL98700017 ER PT J AU HILDNER, ML PONTAU, AE ANTOLAK, AJ WEIRUP, DL AF HILDNER, ML PONTAU, AE ANTOLAK, AJ WEIRUP, DL TI LIMITED DATA RECONSTRUCTIONS FOR ION MICROTOMOGRAPHY (IMT) SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID COMPUTED-TOMOGRAPHY; ERRORS AB Ion microtomography (IMT) is based on measuring the residual energy of ions as they pass through the sample. However, for some samples, the maximum range of the ions can prevent acquiring a complete projection data set for the density reconstruction, i.e., only a limited set of angles will allow the beam to penetrate the sample. Limited angle data sets from flat planar objects are a commonly occurring class for limited data reconstructions in IMT. Such a target can pose an additional problem in that the ion beam may not ''see'' its edges - the target is not finite in extent to the beam. Two reconstruction methods are examined to treat limited data for IMT. The first uses mathematical models of the sample to produce simulated ray-sums that are incorporated into the reconstruction of experimentally measured data. The second method produces a partial reconstruction of the region of interest. A technique is also devised, using a marker, for determining the projected center of rotation - a necessary parameter for the reconstruction algorithms - which cannot be determined from the limited data by usual methods. Examples are presented for two specific planar samples: one made of an artificial heart valve material and the other a metal matrix composite. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP HILDNER, ML (reprint author), SANDIA NATL LABS,LIVERMORE,CA 94551, USA. NR 21 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD MAY PY 1994 VL 88 IS 3 BP 317 EP 330 DI 10.1016/0168-583X(94)95331-7 PG 14 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NL987 UT WOS:A1994NL98700020 ER PT J AU SADOULET, B AF SADOULET, B TI SEARCHES FOR DARK-MATTER SO NUCLEAR PHYSICS B LA English DT Article ID OSCILLATIONS; CANDIDATES; DENSITY; OBJECTS; LIMITS; HALO AB After a rapid review of the fundamental problem of the dark matter in the universe, we present the microlensing candidates which were announced for the first time at the TAUP 93 conference. These events may be the first evidence for Massive Compact Halo Objects and the baryonic dark matter that we know should exist. We then discuss the implication of these observations for the ongoing searches for non-baryonic dark matter and argue that those efforts should be pushed at least as vigorously as before. Finally we review these experiments, focusing in particular on the Weakly Interacting Massive Particles (WIMPs). Our main remarks there are that it is essential to actively reject the background, and that cryogenic detector experiments are coming on line. C1 UNIV CALIF BERKELEY, CTR PARTICLE ASTROPHYS, DEPT PHYS, BERKELEY, CA 94720 USA. LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. NR 49 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1994 SU 35 BP 117 EP 127 DI 10.1016/0920-5632(94)90229-1 PG 11 WC Physics, Particles & Fields SC Physics GA NT280 UT WOS:A1994NT28000018 ER PT J AU SARSA, ML AVIGNONE, FT BRODZINSKI, RL CEREZO, E COLLAR, JI GARCIA, E REEVES, JH MILEY, HS MORALES, A MORALES, J NUNEZLAGOS, R DESOLORZANO, AO PUIMEDON, J SAENZ, C SALINAS, A VILLAR, JA AF SARSA, ML AVIGNONE, FT BRODZINSKI, RL CEREZO, E COLLAR, JI GARCIA, E REEVES, JH MILEY, HS MORALES, A MORALES, J NUNEZLAGOS, R DESOLORZANO, AO PUIMEDON, J SAENZ, C SALINAS, A VILLAR, JA TI DARK-MATTER SEARCHES AT THE CANFRANC TUNNEL SO NUCLEAR PHYSICS B LA English DT Article ID COLD; MODULATION AB Results of an on-going search for particle dark matter with a germanium detector at the Canfranc tunnel are reported. Contour limits for cross-sections, masses and local halo densities of particles interacting through spin-independent interactions are presented. Preliminary results and prospects of a search for timing modulation of the signal are also reported. C1 UNIV ZARAGOZA, FAC CIENCIAS, INST FIS NUCL ALTAS ENERGIAS, E-50009 ZARAGOZA, SPAIN. UNIV S CAROLINA, DEPT PHYS & ASTRON, COLUMBIA, SC 29208 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. RI Sarsa Sarsa, Maria Luisa/K-6108-2014; Villar, Jose Angel/K-6630-2014; Cerezo, Eva /L-6095-2014; OI Sarsa Sarsa, Maria Luisa/0000-0002-7552-1228; Villar, Jose Angel/0000-0003-0228-7589; Cerezo, Eva /0000-0003-4424-0770; Garcia Abancens, Eduardo/0000-0002-9827-2332 NR 16 TC 19 Z9 19 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1994 SU 35 BP 154 EP 158 DI 10.1016/0920-5632(94)90236-4 PG 5 WC Physics, Particles & Fields SC Physics GA NT280 UT WOS:A1994NT28000025 ER PT J AU BERNARDINI, P AHLEN, S AMBROSIO, M ANTOLINI, R AURIEMMA, G BAKER, R BALDINI, A BARBARINO, GC BARISH, BC BATTISTONI, G BELLOTTI, R BEMPORAD, C BILOKON, H BISI, V BLOISE, C BOWER, C BUSSINO, S CAFAGNA, F CALICCHIO, M CAMPANA, D CARBONI, M CECCHINI, S CEI, F CHIARELLA, V CORONA, A COUTU, S DECATALDO, G DEKHISSI, H DEMARZO, C DEVINCENZI, M DICREDICO, A DIEHL, E ERRIQUEZ, O FAVUZZI, C FORTI, C FUSCO, P GIACOMELLI, G GIANNINI, G GIGLIETTO, N GRASSI, M GREEN, P GRILLO, A GUARINO, F GUARNACCIA, P GUSTAVINO, C HABIG, A HANSON, K HEINZ, R HONG, JT IAROCCI, E KATSAVOUNIDIS, E KEARNS, E KYRIAZOPOULOU, S LAMANNA, E LANE, C LEVIN, D LIPARI, P LIU, G LIU, R LONGO, MJ LU, Y LUDLAM, G MANCARELLA, G MANDRIOLI, G MARGIOTTANERI, A MARIN, A MARINI, A MARTELLO, D CHIESA, AM MAZZIOTTA, MN MICHAEL, DG MIKHEYEV, SP MILLER, L MITTELBRUN, M MONACELLI, P MONTENO, M MUFSON, S MUSSER, J NICOLO, D NOLTY, R OKADA, C OSTERIA, G PALAMARA, O PARLATI, S PATERA, V PATRIZII, L PAVESI, B PAZZI, R PECK, CW PETRAKIS, J PETRERA, S PIGNATANO, ND PISTILLI, P RAINO, A REYNOLDSON, J RONGA, F SANZGIRI, A SATRIANO, C SATTA, L SCAPPARONE, E SCHOLBERG, K SCIUBBA, A LUGARESI, PS SEVERI, M SITTA, M SPINELLI, P SPINETTI, M SPURIO, M STEELE, J STEINBERG, R STONE, JL SULAK, LR SURDO, A TARLE, G TOGO, V VALENTE, V VILELA, E WALTER, CW WEBB, R WORSTELL, W AF BERNARDINI, P AHLEN, S AMBROSIO, M ANTOLINI, R AURIEMMA, G BAKER, R BALDINI, A BARBARINO, GC BARISH, BC BATTISTONI, G BELLOTTI, R BEMPORAD, C BILOKON, H BISI, V BLOISE, C BOWER, C BUSSINO, S CAFAGNA, F CALICCHIO, M CAMPANA, D CARBONI, M CECCHINI, S CEI, F CHIARELLA, V CORONA, A COUTU, S DECATALDO, G DEKHISSI, H DEMARZO, C DEVINCENZI, M DICREDICO, A DIEHL, E ERRIQUEZ, O FAVUZZI, C FORTI, C FUSCO, P GIACOMELLI, G GIANNINI, G GIGLIETTO, N GRASSI, M GREEN, P GRILLO, A GUARINO, F GUARNACCIA, P GUSTAVINO, C HABIG, A HANSON, K HEINZ, R HONG, JT IAROCCI, E KATSAVOUNIDIS, E KEARNS, E KYRIAZOPOULOU, S LAMANNA, E LANE, C LEVIN, D LIPARI, P LIU, G LIU, R LONGO, MJ LU, Y LUDLAM, G MANCARELLA, G MANDRIOLI, G MARGIOTTANERI, A MARIN, A MARINI, A MARTELLO, D CHIESA, AM MAZZIOTTA, MN MICHAEL, DG MIKHEYEV, SP MILLER, L MITTELBRUN, M MONACELLI, P MONTENO, M MUFSON, S MUSSER, J NICOLO, D NOLTY, R OKADA, C OSTERIA, G PALAMARA, O PARLATI, S PATERA, V PATRIZII, L PAVESI, B PAZZI, R PECK, CW PETRAKIS, J PETRERA, S PIGNATANO, ND PISTILLI, P RAINO, A REYNOLDSON, J RONGA, F SANZGIRI, A SATRIANO, C SATTA, L SCAPPARONE, E SCHOLBERG, K SCIUBBA, A LUGARESI, PS SEVERI, M SITTA, M SPINELLI, P SPINETTI, M SPURIO, M STEELE, J STEINBERG, R STONE, JL SULAK, LR SURDO, A TARLE, G TOGO, V VALENTE, V VILELA, E WALTER, CW WEBB, R WORSTELL, W TI MUON ASTROPHYSICS WITH THE MACRO DETECTOR SO NUCLEAR PHYSICS B LA English DT Article ID GRAN-SASSO AB Muon events collected with the streamer tube system of MACRO have been used to study the vertical muon intensity and to search for astrophysical point sources. New upper limits on the muon fluxes coming from source candidates have been obtained. The mu pair distance distribution and multimuon rates are presented and compared with Monte Carlo predictions for different primary cosmic rays composition models. C1 UNIV BARI, DIPARTIMENTO FIS, I-70124 BARI, ITALY. INFN, BARI, ITALY. UNIV BOLOGNA, DIPARTIMENTO FIS, I-40126 BOLOGNA, ITALY. INFN, BOLOGNA, ITALY. BOSTON UNIV, DEPT PHYS, BOSTON, MA 02215 USA. CALTECH, PASADENA, CA 91125 USA. DREXEL UNIV, DEPT PHYS, PHILADELPHIA, PA 19104 USA. INFN, NAZL FRASCATI LAB, FRASCATI, ITALY. INFN, LAB NAZL GRAN SASSO, LAQUILA, ITALY. INDIANA UNIV, DEPT PHYS, BLOOMINGTON, IN 47401 USA. INDIANA UNIV, DEPT ASTRON, BLOOMINGTON, IN 47401 USA. UNIV LAQUILA, DIPARTIMENTO FIS, I-67100 LAQUILA, ITALY. UNIV MICHIGAN, DEPT PHYS, ANN ARBOR, MI 48109 USA. UNIV NAPLES, DIPARTIMENTO FIS, I-80138 NAPLES, ITALY. INFN, NAPLES, ITALY. UNIV PISA, DIPARTIMENTO FIS, I-56100 PISA, ITALY. INFN, PISA, ITALY. UNIV ROME, DIPARTIMENTO FIS, I-00100 ROME, ITALY. INFN, ROME, ITALY. TEXAS A&M UNIV, DEPT PHYS, COLLEGE STN, TX 77843 USA. UNIV TURIN, DIPARTIMENTO FIS, I-10124 TURIN, ITALY. INFN, TURIN, ITALY. UNIV DELAWARE, BARTOL RES INST, NEWARK, DE 19718 USA. SANDIA NATL LABS, ALBUQUERQUE, NM 87185 USA. UNIV BASILICATA, POTENZA, ITALY. CNR, IST TESRE, I-40126 BOLOGNA, ITALY. UNIV CAMERINO, I-62032 CAMERINO, ITALY. UNIV TRIESTE, I-34100 TRIESTE, ITALY. INFN, TRIESTE, ITALY. UNIV ROME, DIPARTIMENTO ENERGET, I-00100 ROME, ITALY. RUSSIAN ACAD SCI, INST NUCL RES, MOSCOW, RUSSIA. UNIV MOHAMMED IST, OUJDA, MOROCCO. SCUOLA NORMALE SUPER PISA, I-56100 PISA, ITALY. RI Cafagna, Francesco/A-9299-2010; Guarino, Fausto/I-3166-2012; Spurio, Maurizio/G-4170-2012; giglietto, nicola/I-8951-2012; Lamanna, Ernesto/C-7658-2012; Barbarino, Giancarlo/L-2559-2015; Martello, Daniele/J-3131-2012; Mazziotta, Mario /O-8867-2015; Cei, Fabrizio/M-8891-2016; gustavino, carlo/K-4355-2015; OI Cafagna, Francesco/0000-0002-7450-4784; Guarino, Fausto/0000-0003-1427-9885; giglietto, nicola/0000-0002-9021-2888; Lamanna, Ernesto/0000-0002-7844-8230; Barbarino, Giancarlo/0000-0001-9253-3397; Martello, Daniele/0000-0003-2046-3910; Mazziotta, Mario /0000-0001-9325-4672; Cei, Fabrizio/0000-0002-8313-3540; Bellotti, Roberto/0000-0003-3198-2708; gustavino, carlo/0000-0003-3232-7027; Sciubba, Adalberto/0000-0002-3301-9176; Monteno, Marco/0000-0002-3521-6333; ERRIQUEZ, Onofrio/0000-0002-9784-6568; Carboni, Massimo/0000-0003-4296-3799; Petrera, Sergio/0000-0002-6029-1255; Coutu, Stephane/0000-0003-2923-2246 NR 11 TC 0 Z9 0 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1994 SU 35 BP 229 EP 234 DI 10.1016/0920-5632(94)90248-8 PG 6 WC Physics, Particles & Fields SC Physics GA NT280 UT WOS:A1994NT28000037 ER PT J AU NAVARRA, G AHLEN, S AMBROSIO, M ANTOLINI, R AURIEMMA, G BAKER, R BALDINI, A BARBARINO, GC BARISH, BC BATTISTONI, G BELLOTTI, R BEMPORAD, C BERNARDINI, P BILOKON, H BISI, V BLOISE, C BOWER, C BUSSINO, S CAFAGNA, F CALICCHIO, M CAMPANA, D CARBONI, M CECCHINI, S CEI, F CHIARELLA, V CORONA, A COUTU, S DECATALDO, G DEKHISSI, H DEMARZO, C DEVINCENZI, M DICREDICO, A DIEHL, E ERRIQUEZ, O FAVUZZI, C FORTI, C FUSCO, P GIACOMELLI, G GIANNINI, G GIGLIETTO, N GRASSI, M GREEN, P GRILLO, A GUARINO, F GUARNACCIA, P GUSTAVINO, C HABIG, A HANSON, K HEINZ, R HONG, JT IAROCCI, E KATSAVOUNIDIS, E KEARNS, E KYRIAZOPOULOU, S LAMANNA, E LANE, C LEVIN, D LIPARI, P LIU, G LIU, R LONGO, MJ LU, Y LUDLAM, G MANCARELLA, G MANDRIOLI, G MARGIOTTANERI, A MARIN, A MARINI, A MARTELLO, D CHIESA, AM MAZZIOTTA, MN MICHAEL, DG MIKHEYEV, SP MILLER, L MITTELBRUN, M MONACELLI, P MONTENO, M MUFSON, S MUSSER, J NICOLO, D NOLTY, R OKADA, C OSTERIA, G PALAMARA, O PARLATI, S PATERA, V PATRIZII, L PAVESI, B PAZZI, R PECK, CW PETRAKIS, J PETRERA, S PIGNATANO, ND PISTILLI, P RAINO, A REYNOLDSON, J RONGA, F SANZGIRI, A SATRIANO, C SATTA, L SCAPPARONE, E SCHOLBERG, K SCIUBBA, A LUGARESI, PS SEVERI, M SITTA, M SPINELLI, P SPINETTI, M SPURIO, M STEELE, J STEINBERG, R STONE, JL SULAK, LR SURDO, A TARLE, G TOGO, V VALENTE, V VILELA, E WALTER, CW WEBB, R WORSTELL, W AF NAVARRA, G AHLEN, S AMBROSIO, M ANTOLINI, R AURIEMMA, G BAKER, R BALDINI, A BARBARINO, GC BARISH, BC BATTISTONI, G BELLOTTI, R BEMPORAD, C BERNARDINI, P BILOKON, H BISI, V BLOISE, C BOWER, C BUSSINO, S CAFAGNA, F CALICCHIO, M CAMPANA, D CARBONI, M CECCHINI, S CEI, F CHIARELLA, V CORONA, A COUTU, S DECATALDO, G DEKHISSI, H DEMARZO, C DEVINCENZI, M DICREDICO, A DIEHL, E ERRIQUEZ, O FAVUZZI, C FORTI, C FUSCO, P GIACOMELLI, G GIANNINI, G GIGLIETTO, N GRASSI, M GREEN, P GRILLO, A GUARINO, F GUARNACCIA, P GUSTAVINO, C HABIG, A HANSON, K HEINZ, R HONG, JT IAROCCI, E KATSAVOUNIDIS, E KEARNS, E KYRIAZOPOULOU, S LAMANNA, E LANE, C LEVIN, D LIPARI, P LIU, G LIU, R LONGO, MJ LU, Y LUDLAM, G MANCARELLA, G MANDRIOLI, G MARGIOTTANERI, A MARIN, A MARINI, A MARTELLO, D CHIESA, AM MAZZIOTTA, MN MICHAEL, DG MIKHEYEV, SP MILLER, L MITTELBRUN, M MONACELLI, P MONTENO, M MUFSON, S MUSSER, J NICOLO, D NOLTY, R OKADA, C OSTERIA, G PALAMARA, O PARLATI, S PATERA, V PATRIZII, L PAVESI, B PAZZI, R PECK, CW PETRAKIS, J PETRERA, S PIGNATANO, ND PISTILLI, P RAINO, A REYNOLDSON, J RONGA, F SANZGIRI, A SATRIANO, C SATTA, L SCAPPARONE, E SCHOLBERG, K SCIUBBA, A LUGARESI, PS SEVERI, M SITTA, M SPINELLI, P SPINETTI, M SPURIO, M STEELE, J STEINBERG, R STONE, JL SULAK, LR SURDO, A TARLE, G TOGO, V VALENTE, V VILELA, E WALTER, CW WEBB, R WORSTELL, W TI STUDY OF THE COSMIC-RAY PRIMARY COMPOSITION AT E0-SIMILAR-TO-1000TEV BY EAS-TOP AND MACRO AT GRAN-SASSO SO NUCLEAR PHYSICS B LA English DT Article ID DEEP-UNDERGROUND MUONS; ENERGY-SPECTRA; DETECTOR AB An analysis of the coincident deep underground muon data and of the e.m. component of Extensive Air Showers (EAS) as measured by the MACRO and EAS-TOP experiments at Gran Sasso is presented. Constraints on the primary cosmic ray composition are obtained, with the use of an interaction model that is based on collider data. The possibility of extrapolating the directly measured energy spectra to our energy range is tested. C1 UNIV TURIN, IST FIS GEN, I-10125 TURIN, ITALY. UNIV BARI, DIPARTIMENTO FIS, I-70124 BARI, ITALY. INFN, BARI, ITALY. UNIV BOLOGNA, DIPARTIMENTO FIS, I-40126 BOLOGNA, ITALY. INFN, BOLOGNA, ITALY. BOSTON UNIV, DEPT PHYS, BOSTON, MA 02215 USA. CALTECH, PASADENA, CA 91125 USA. DREXEL UNIV, DEPT PHYS, PHILADELPHIA, PA 19104 USA. INFN, LAB NAZL GRAN SASSO, LAQUILA, ITALY. INDIANA UNIV, DEPT PHYS, BLOOMINGTON, IN 47401 USA. INDIANA UNIV, DEPT ASTRON, BLOOMINGTON, IN 47401 USA. UNIV LAQUILA, DIPARTIMENTO FIS, I-67100 LAQUILA, ITALY. UNIV MICHIGAN, DEPT PHYS, ANN ARBOR, MI 48109 USA. UNIV NAPLES, DIPARTIMENTO FIS, I-80138 NAPLES, ITALY. INFN, NAPLES, ITALY. UNIV PISA, DIPARTIMENTO FIS, I-56100 PISA, ITALY. INFN, PISA, ITALY. UNIV ROME, DIPARTIMENTO FIS, I-00100 ROME, ITALY. INFN, ROME, ITALY. TEXAS A&M UNIV, DEPT PHYS, COLLEGE STN, TX 77843 USA. UNIV TURIN, DIPARTIMENTO FIS, I-10124 TURIN, ITALY. INFN, TURIN, ITALY. UNIV DELAWARE, BARTOL RES INST, NEWARK, DE 19718 USA. SANDIA NATL LABS, ALBUQUERQUE, NM 87185 USA. UNIV BASILICATA, POTENZA, ITALY. CNR, IST TESRE, I-40126 BOLOGNA, ITALY. UNIV CAMERINO, I-62032 CAMERINO, ITALY. UNIV TRIESTE, I-34100 TRIESTE, ITALY. INFN, TRIESTE, ITALY. UNIV ROME, DIPARTIMENTO ENERGET, I-00100 ROME, ITALY. RUSSIAN ACAD SCI, INST NUCL RES, MOSCOW, RUSSIA. UNIV MOHAMMED IST, OUJDA, MOROCCO. SCUOLA NORMALE SUPER PISA, I-56100 PISA, ITALY. INFN, NAZL FRASCATI LAB, FRASCATI, ITALY. RI Spurio, Maurizio/G-4170-2012; giglietto, nicola/I-8951-2012; Cafagna, Francesco/A-9299-2010; Lamanna, Ernesto/C-7658-2012; Barbarino, Giancarlo/L-2559-2015; Martello, Daniele/J-3131-2012; Mazziotta, Mario /O-8867-2015 OI giglietto, nicola/0000-0002-9021-2888; Cafagna, Francesco/0000-0002-7450-4784; Lamanna, Ernesto/0000-0002-7844-8230; Barbarino, Giancarlo/0000-0001-9253-3397; Martello, Daniele/0000-0003-2046-3910; Mazziotta, Mario /0000-0001-9325-4672 NR 14 TC 0 Z9 0 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1994 SU 35 BP 257 EP 258 DI 10.1016/0920-5632(94)90255-0 PG 2 WC Physics, Particles & Fields SC Physics GA NT280 UT WOS:A1994NT28000044 ER PT J AU SCHRAMM, DN SHI, X AF SCHRAMM, DN SHI, X TI SOLAR NEUTRINOS - SOLAR PHYSICS AND NEUTRINO PHYSICS SO NUCLEAR PHYSICS B LA English DT Article ID KAMIOKANDE-II DETECTOR; CROSS-SECTION; CAPTURE RATE; OSCILLATIONS; MATTER; SUN; MODEL; FLUX; HELIOSEISMOLOGY; UNCERTAINTIES AB It is shown that the current solar neutrino situation, with results from the Homestake experiment, the Kamiokande experiment, GALLEX and SAGE is unfortunately still ambiguous. The differences between observations and the standard solar theory may still be due to either astrophysical inputs or new neutrino physics. The need for new neutrino physics, MSW or vacuum neutrino mixing is sensitive to the results of the Homestake experiment. If the Homestake experiment is correct, then new neutrino physics is required. A problem with the uncalibrated Homestake experiment would allow an astrophysical solution, which merely consists of a slightly cooler sun than the standard solar model of Bahcall et al. The use of future experiments, SNO, Super Kamiokande and Borexino to resolve this ambiguity are explicitly discussed. The measurement of deeper helioseismology modes by GONG will also further constrain solar model solutions. C1 UNIV CHICAGO, CHICAGO, IL 60637 USA. FERMILAB NATL ACCELERATOR LAB, NASA, FERMILAB ASTROPHYS CTR, BATAVIA, IL 60510 USA. NR 56 TC 4 Z9 4 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1994 SU 35 BP 321 EP 333 DI 10.1016/0920-5632(94)90271-2 PG 13 WC Physics, Particles & Fields SC Physics GA NT280 UT WOS:A1994NT28000060 ER PT J AU AVIGNONE, FT BRODZINSKI, RL COLLAR, JI COURANT, H GARCIA, E GUERARD, CK HENSLEY, WK KIRPICHNIKOV, IV KLIMENKO, AA MORALES, A MORALES, J MILEY, HS NUNEZLAGOS, R OSETROV, SB POGOSOV, VS POMANSKY, AA PUIMEDON, J REEVES, JH RUDDICK, K SAENZ, C SALINAS, A SARSA, ML SMOLNIKOV, AA STAROSTIN, AS TAMANYAN, AG UMATOV, VI VASILIEV, SI VILLAR, JA AF AVIGNONE, FT BRODZINSKI, RL COLLAR, JI COURANT, H GARCIA, E GUERARD, CK HENSLEY, WK KIRPICHNIKOV, IV KLIMENKO, AA MORALES, A MORALES, J MILEY, HS NUNEZLAGOS, R OSETROV, SB POGOSOV, VS POMANSKY, AA PUIMEDON, J REEVES, JH RUDDICK, K SAENZ, C SALINAS, A SARSA, ML SMOLNIKOV, AA STAROSTIN, AS TAMANYAN, AG UMATOV, VI VASILIEV, SI VILLAR, JA TI THE INTERNATIONAL GERMANIUM EXPERIMENT (IGEX) IN 1993 SO NUCLEAR PHYSICS B LA English DT Article ID DOUBLE-BETA-DECAY; GE-76 AB The data collected from the first set of three IGEX enriched germanium detectors have been analyzed. The best background obtained was less than 0.3 counts/keV/kg/y near 2 MeV, obtained in the Homestake gold mine in Lead, SD, USA. Data combined from all the detectors yield T1/2(0nu) less-than-or-equal-to 1.0 X 10(24)y (90% CL). The first detector produced in the second phase of the experiment is a 2.15 kg germanium crystal of 2.16 keV FWHM at 1332 keV. Several experiences with the first group of detectors have led to improvements in the mechanical design of the copper cryostat. Also, low background materials research done in the last two years has lowered the specific activity of the electroformed copper. The new detector is currently operating in the Homestake gold mine. C1 UNIV S CAROLINA, COLUMBIA, SC 29208 USA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. INST THEORET & EXPTL PHYS, 117259 MOSCOW, RUSSIA. UNIV MINNESOTA, MINNEAPOLIS, MN 55455 USA. BAKSAN NEUTRINO OBSERV, INST NUCL RES, 361609 NEUTRINO, RUSSIA. UNIV ZARAGOZA, ZARAGOZA, SPAIN. YEREVAN PHYS INST, 375036 YEREVAN, ARMENIA. KURCHATOV INST ATOM ENERGY, 142092 MOSCOW, RUSSIA. RI Sarsa Sarsa, Maria Luisa/K-6108-2014; Villar, Jose Angel/K-6630-2014; OI Sarsa Sarsa, Maria Luisa/0000-0002-7552-1228; Villar, Jose Angel/0000-0003-0228-7589; Garcia Abancens, Eduardo/0000-0002-9827-2332 NR 8 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1994 SU 35 BP 354 EP 357 DI 10.1016/0920-5632(94)90275-5 PG 4 WC Physics, Particles & Fields SC Physics GA NT280 UT WOS:A1994NT28000064 ER PT J AU MILEY, HS ARTHUR, RJ AVIGNONE, FT BARABASH, AS BRODZINSKI, RL COLLAR, JI COURANT, H GARCIA, E GUERARD, CK HENSLEY, WK KIRPICHNIKOV, IV KLIMENKO, AA MORALES, A MORALES, J NUNEZLAGOS, R OSETROV, SB POGOSOV, VS PUIMEDON, J REEVES, JH RUDDICK, K SAENZ, C SALINAS, A SARSA, ML SMOLNIKOV, AA STAROSTIN, AS TAMANYAN, AG UMATOV, VI VASILIEV, SI VILLAR, JA AF MILEY, HS ARTHUR, RJ AVIGNONE, FT BARABASH, AS BRODZINSKI, RL COLLAR, JI COURANT, H GARCIA, E GUERARD, CK HENSLEY, WK KIRPICHNIKOV, IV KLIMENKO, AA MORALES, A MORALES, J NUNEZLAGOS, R OSETROV, SB POGOSOV, VS PUIMEDON, J REEVES, JH RUDDICK, K SAENZ, C SALINAS, A SARSA, ML SMOLNIKOV, AA STAROSTIN, AS TAMANYAN, AG UMATOV, VI VASILIEV, SI VILLAR, JA TI SIMULATED PROGRESS IN DOUBLE-BETA DECAY SO NUCLEAR PHYSICS B LA English DT Article AB A Monte Carlo code has been developed to accurately simulate double-beta decay measurements. Coincident gamma rays, beta spectra, and angular correlations have been added to adequately simulate a complete Mo-100 nuclear decay and provide corrections to experimentally determined detector efficiencies. This code has been used to strip certain low-background spectra obtained in the Homestake gold mine in Lead, SD, for the purpose of extremely sensitive materials assay for the construction of new, large, enriched germanium detectors. Assays as low as 9 muBq/g of Pb-210 in lead shielding were obtained. C1 INST THEORET & EXPTL PHYS, 117259 MOSCOW, RUSSIA. UNIV ZARAGOZA, ZARAGOZA, SPAIN. BAKSAN NEUTRINO OBSERV, INST NUCL RES, 361609 NEUTRINO, RUSSIA. YEREVAN PHYS INST, 375036 YEREVAN, ARMENIA. KURCHATOV INST ATOM ENERGY, 142092 MOSCOW, RUSSIA. PACIFIC NW LAB, RICHLAND, WA 99352 USA. UNIV S CAROLINA, COLUMBIA, SC 29208 USA. UNIV MINNESOTA, MINNEAPOLIS, MN 55455 USA. RI Sarsa Sarsa, Maria Luisa/K-6108-2014; Villar, Jose Angel/K-6630-2014; Barabash, Alexander/S-8851-2016; OI Sarsa Sarsa, Maria Luisa/0000-0002-7552-1228; Villar, Jose Angel/0000-0003-0228-7589; Garcia Abancens, Eduardo/0000-0002-9827-2332 NR 1 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1994 SU 35 BP 388 EP 390 DI 10.1016/0920-5632(94)90286-0 PG 3 WC Physics, Particles & Fields SC Physics GA NT280 UT WOS:A1994NT28000075 ER PT J AU GAVRIN, VN FAIZOV, EL KALIKHOV, AV KNODEL, TV KNYSHENKO, II KORNOUKHOV, VN MIRMOV, IN OSTRINSKY, AV PSHUKOV, AM SHIKHIN, AA TIMOFEYEV, PV VERETENKIN, EP VERMUL, VM ZATSEPIN, GT BOWLES, TJ ELLIOTT, SR NICO, JS TEASDALE, WA WARK, DL WILKERSON, JF CLEVELAND, BT DAILY, T DAVIS, R LANDE, K LEE, CK WILDENHAIN, P CHERRY, ML KOUZES, RT AF GAVRIN, VN FAIZOV, EL KALIKHOV, AV KNODEL, TV KNYSHENKO, II KORNOUKHOV, VN MIRMOV, IN OSTRINSKY, AV PSHUKOV, AM SHIKHIN, AA TIMOFEYEV, PV VERETENKIN, EP VERMUL, VM ZATSEPIN, GT BOWLES, TJ ELLIOTT, SR NICO, JS TEASDALE, WA WARK, DL WILKERSON, JF CLEVELAND, BT DAILY, T DAVIS, R LANDE, K LEE, CK WILDENHAIN, P CHERRY, ML KOUZES, RT TI RECENT RESULTS FROM SAGE SO NUCLEAR PHYSICS B LA English DT Article ID SOLAR AB A radiochemical Ga-71-Ge-71 experiment to determine the primary flux of neutrinos from the Sun began measurements of the solar neutrino flux at the Baksan Neutrino Observatory in 1990. The number of Ge-71 atoms extracted from initially 30 and later 57 tons of metallic gallium was measured in fifteen runs during the period of January 1990 to May 1992. The observed capture rate is 70 +/- 19 (stat) +/- 10 (syst) SNU. This is to be compared with 132 SNU predicted by the Standard Solar Model. C1 RUSSIAN ACAD SCI, INST NUCL RES, MOSCOW 117312, RUSSIA. LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. UNIV PENN, PHILADELPHIA, PA 19104 USA. LOUISIANA STATE UNIV, BATON ROUGE, LA 70803 USA. PRINCETON UNIV, PRINCETON, NJ 08544 USA. OI Wilkerson, John/0000-0002-0342-0217 NR 9 TC 13 Z9 13 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1994 SU 35 BP 412 EP 417 DI 10.1016/0920-5632(94)90294-1 PG 6 WC Physics, Particles & Fields SC Physics GA NT280 UT WOS:A1994NT28000083 ER PT J AU KAFKA, T AF KAFKA, T TI CONTAINED NEUTRINO EVENTS IN SOUDAN-2 SO NUCLEAR PHYSICS B LA English DT Article ID ATMOSPHERIC FLUX AB Preliminary results from the first kiloton-year of exposure of Soudan-2 are presented. Our value for the nu(mu)/nu(e) ratio-of-ratios, 0.69 +/- 0.19 +/- 0.09, does not contradict the ''atmospheric neutrino anomaly' previously found by underground water detectors, as did earlier underground calorimeter experiments. C1 UNIV MINNESOTA, MINNEAPOLIS, MN 55455 USA. TUFTS UNIV, MEDFORD, MA 02155 USA. ARGONNE NATL LAB, ARGONNE, IL 60439 USA. UNIV OXFORD, RUTHERFORD APPLETON LAB, OXFORD, ENGLAND. NR 10 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAY PY 1994 SU 35 BP 427 EP 429 PG 3 WC Physics, Particles & Fields SC Physics GA NT280 UT WOS:A1994NT28000085 ER PT J AU GELBARD, EM GU, AG AF GELBARD, EM GU, AG TI BIASES IN MONTE-CARLO EIGENVALUE CALCULATIONS SO NUCLEAR SCIENCE AND ENGINEERING LA English DT Article AB The derivation of the standard expression for the Monte Carlo eigenvalue bias is reviewed. It is noted that the bias is due to the repeated normalization of the fission source by the eigenvalue. This normalization can be partially or completely eliminated, but when this is done, the variance in the eigenvalue may increase unacceptably. Thus, it seems impractical, in general, to eliminate the bias in this way. Next, the Brissenden-Garlick relation between eigenvalue bias and variance is rederived for nonanalog tracking and estimation. From this relation, it is shown that the eigenvalue bias under ''normal'' conditions is smaller than the eigenvalue's standard deviation. In this sense, the bias is not significant, so that it is not crucially important to eliminate or to estimate it. C1 MISSISSIPPI STATE UNIV,MISSISSIPPI STATE,MS 39762. RP GELBARD, EM (reprint author), ARGONNE NATL LAB,DIV REACTOR ANAL,ARGONNE,IL 60439, USA. NR 9 TC 12 Z9 12 U1 0 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5639 J9 NUCL SCI ENG JI Nucl. Sci. Eng. PD MAY PY 1994 VL 117 IS 1 BP 1 EP 9 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA NU309 UT WOS:A1994NU30900001 ER PT J AU HASKIN, FE HUANG, M SASSER, MK STACK, DW AF HASKIN, FE HUANG, M SASSER, MK STACK, DW TI MEAN IMPORTANCE MEASURES FOR GROUPS OF EVENTS IN FAULT-TREES SO NUCLEAR TECHNOLOGY LA English DT Article DE UNCERTAINTY ANALYSIS; SENSITIVITY ANALYSIS; K-REACTOR ID UNCERTAINTY; UNAVAILABILITY; SENSITIVITY AB The method of moments is applied to precisely determine the mean values of three importance measures: risk reduction, partial derivative, and variance reduction. Variance reduction calculations, in particular, are significantly improved by eliminating the imprecision associated with Monte Carlo estimates. The three importance measures are extended to permit analyses of the relative importance of groups of basic and initiating events. The partial derivative importance measure is extended by assessing the contribution of a group of events to the gradient of the top event frequency. The group importance measures are quantified for the overall fuel damage equation and for 14 dominant accident sequences from an independent probabilistic safety assessment of the K Production Reactor. This application demonstrates both the utility and the versatility of the group importance measures. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. RP HASKIN, FE (reprint author), UNIV NEW MEXICO,DEPT CHEM & NUCL ENGN,FARRIS ENGN CTR,ALBUQUERQUE,NM 87131, USA. NR 12 TC 3 Z9 3 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAY PY 1994 VL 106 IS 2 BP 155 EP 167 PG 13 WC Nuclear Science & Technology SC Nuclear Science & Technology GA NH409 UT WOS:A1994NH40900002 ER PT J AU BOTTONI, M LYCZKOWSKI, RW AF BOTTONI, M LYCZKOWSKI, RW TI MODELING OF BUBBLY AND ANNULAR 2-PHASE FLOW IN SUBCHANNEL GEOMETRIES WITH BACCHUS-3D/TP SO NUCLEAR TECHNOLOGY LA English DT Article DE COMPUTER MODELING; BUBBLY-ANNULAR FLOW; FAST REACTORS ID COMPUTER-PROGRAM; BUNDLES AB The theoretical and computational bases of the BACCHUS-3D/TP computer program are reviewed. The computer program has been developed in the frame of the liquid-metal fast breeder reactor safety project at the Kernforschungszentrum Karlsruhe and is used for thermal-hydraulic analyses of nuclear fuel bundles under normal and accident conditions. The present program combines two models and solution procedures previously used separately, namely, an improved slip model and a separated-phases model. The first model uses mixture equations and accounts for slip between the phases, whereas the latter uses separate continuity and momentum equations. At the present stage of development, both assume thermodynamic equilibrium. Techniques used to affect smooth transitions between the two models are described, including treatment of frictional pressure drop and solution of the Poisson pressure and momentum equations. A detailed derivation of the computation of mass transfer between the phases is given because it is a central and novel feature of the model. A summary of validations performed to date, together with the quantities measured and compared with computations is given in tabular form. RP BOTTONI, M (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 28 TC 1 Z9 1 U1 1 U2 1 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAY PY 1994 VL 106 IS 2 BP 186 EP 201 PG 16 WC Nuclear Science & Technology SC Nuclear Science & Technology GA NH409 UT WOS:A1994NH40900005 ER PT J AU REIFMAN, J VITELA, JE AF REIFMAN, J VITELA, JE TI ACCELERATING LEARNING OF NEURAL NETWORKS WITH CONJUGATE GRADIENTS FOR NUCLEAR-POWER-PLANT APPLICATIONS SO NUCLEAR TECHNOLOGY LA English DT Article DE ARTIFICIAL NEURAL NETWORKS; CONJUGATE GRADIENTS; PREMATURE SATURATION; PROCESS FAULT DIAGNOSIS AB The method of conjugate gradients is used to expedite the learning process of feedforward multilayer artificial neural networks and to systematically update both the learning parameter and the momentum parameter at each training cycle. The mechanism for the occurrence of premature saturation of the network nodes observed with the backpropagation algorithm is described, suggestions are made to eliminate this undesirable phenomenon, and the reason by which this phenomenon is precluded in the method of conjugate gradients is presented. The proposed method is compared with the standard backpropagation algorithm in the training of neural networks to classify transient events in nuclear power plants simulated by the Midland Nuclear Power Plant Unit 2 simulator. The comparison results indicate that the rate of convergence of the proposed method is much greater than the standard backpropagation, that it reduces both the number of training cycles and the CPU time, and that it is less sensitive to the choice of initial weights. The advantages of the method are more noticeable and important for problems where the network architecture consists of a large number of nodes, the training database is large, and a tight convergence criterion is desired. C1 NATL AUTONOMOUS UNIV MEXICO,INST CIENCIAS NUCL,MEXICO CITY 04510,DF,MEXICO. RP REIFMAN, J (reprint author), ARGONNE NATL LAB,DIV REACTOR ANAL,ARGONNE,IL 60439, USA. NR 34 TC 22 Z9 22 U1 2 U2 2 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAY PY 1994 VL 106 IS 2 BP 225 EP 241 PG 17 WC Nuclear Science & Technology SC Nuclear Science & Technology GA NH409 UT WOS:A1994NH40900008 ER PT J AU SMITH, AC BLAKE, JE CHILDERSON, MT OHRN, TR PRIVETTE, RM AF SMITH, AC BLAKE, JE CHILDERSON, MT OHRN, TR PRIVETTE, RM TI LOW-POWER EXPERIMENTAL-STUDY OF THE DEMAND SURFACE FOR ANNULAR GEOMETRY FUEL-ELEMENTS WITH UPFLOW OF COOLANT SO NUCLEAR TECHNOLOGY LA English DT Article DE DEMAND SURFACE; ANNULAR GEOMETRY; FUEL ELEMENT AB Analytical studies of the effects of power on flow instability in parallel channels with upward flow of coolant have predicted that the Ledinegg flow instability, encountered as flow is decreased for typical operating power levels, would not be experienced at low-power levels. For a system in which the flow of coolant is upward, the increased buoyancy enhances flow in the channel, so that as the void increases, the overall pressure loss decreases. Under this condition, flow instability does not occur. Testing was performed to confirm the predicted behavior and to provide data for benchmarking of computer codes used for predicting the performance of reactor fuel elements. The demand curves traced in these tests are part of the multidimensional demand surface for the test apparatus. The basic coordinates of this surface are flow rate, pressure drop, and power. A fourth significant independent variable is system pressure, so that the behavior of the system is represented by a family of DELTAp-flow-power surfaces for each pressure level. This testing confirmed that, at low power levels comparable to decay heat removal power, the buoyancy effects may become dominant so that the demand curve for the fuel assembly turns down ward and flow instability will not occur. C1 BABCOCK & WILCOX CO,DIV RES & DEV,ALLIANCE,OH 44601. RP SMITH, AC (reprint author), WESTINGHOUSE SAVANNAH RIVER CO,SAVANNAH RIVER SITE,POB 616,AIKEN,SC 29808, USA. NR 8 TC 0 Z9 0 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD MAY PY 1994 VL 106 IS 2 BP 254 EP 260 PG 7 WC Nuclear Science & Technology SC Nuclear Science & Technology GA NH409 UT WOS:A1994NH40900010 ER PT J AU Joubert, W Oppe, T AF Joubert, Wayne Oppe, Thomas TI Improved SSOR and Incomplete Cholesky Solution of Linear Equations on Shared Memory and Distributed Memory Parallel Computers SO NUMERICAL LINEAR ALGEBRA WITH APPLICATIONS LA English DT Article DE Linear systems; Incomplete factorizations; Parallel computation AB In this paper two new implementations of SSOR and incomplete factorization preconditioners are given, for shared memory and distributed memory parallel computers respectively. These new implementations give increased solution speeds for matrix problems such as those arising from discretized partial differential equations with natural ordering of the grid points, for which it is well-known that the standard implementation of these preconditioners is difficult to parallelize effectively. For shared memory machines, a new technique is presented here which decreases the number of synchronization points in each preconditioning step and thus allows better parallel speedups. For distributed memory machines, an implementation based on block cyclic reduction is given which circumvents the problem of idle processors during the preconditioning phase. Descriptions of the implementations are given, and numerical comparisons are given for a model diffusion problem on the Cray Y-MP and the CM-2 Connection Machine. C1 [Joubert, Wayne] Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. [Oppe, Thomas] Florida State Univ, Supercomp Computat & Res Inst, Tallahassee, FL 32306 USA. RP Joubert, W (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. FU Department of Energy [DE-FG05-87ER2.5048, W-7405-ENG-36]; University of Texas at Austin; National Science Foundation [DCR-8518722]; Cray Research Inc. [LTRDTD 1/18/90]; Advanced Computing Laboratory of Los Alamos National Laboratory; Schlumberger Laboratory for Computer Science; Los Alamos National Laboratory FX This work was supported in part by the Department of Energy through Grant DE-FG05-87ER2.5048 with the University of Texas at Austin, by the National Science Foundation through Grant DCR-8518722, by Cray Research Inc. through Grant LTRDTD 1/18/90, by the Advanced Computing Laboratory of Los Alamos National Laboratory and by the Schlumberger Laboratory for Computer Science. This work was also supported in part by the Department of Energy through grant W-7405-ENG-36, with Los Alamos National Laboratory. NR 22 TC 2 Z9 2 U1 0 U2 0 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 1070-5325 EI 1099-1506 J9 NUMER LINEAR ALGEBR JI Numer. Linear Algebr. Appl. PD MAY-JUN PY 1994 VL 1 IS 3 BP 287 EP 311 DI 10.1002/nla.1680010306 PG 25 WC Mathematics, Applied; Mathematics SC Mathematics GA V32PZ UT WOS:000208964400005 ER PT J AU WRIGHT, SJ AF WRIGHT, SJ TI STABLE PARALLEL ELIMINATION FOR BOUNDARY-VALUE ODES SO NUMERISCHE MATHEMATIK LA English DT Article ID ALGORITHMS; STABILITY AB A parallelizable and vectorizable algorithm for solving linear algebraic systems arising from two-point boundary value ODEs is described. The method is equivalent to Gaussian elimination, with row partial pivoting, applied to a certain column-reordered version of the usual almost-block-diagonal coefficient matrix. We present analytical and numerical evidence to show that the algorithm is stable in most circumstances. Results from implementation on a shared-memory multiprocessor and a vector processor are given. The approach can be extended to handle problems with multipoint and integral conditions or with algebraic parameters. RP WRIGHT, SJ (reprint author), ARGONNE NATL LAB,DIV MATH & COMP SCI,ARGONNE,IL 60439, USA. NR 13 TC 11 Z9 11 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0029-599X J9 NUMER MATH JI Numer. Math. PD MAY PY 1994 VL 67 IS 4 BP 521 EP 535 DI 10.1007/s002110050043 PG 15 WC Mathematics, Applied SC Mathematics GA NP618 UT WOS:A1994NP61800009 ER PT J AU SANGER, MJ ANGELICI, RJ AF SANGER, MJ ANGELICI, RJ TI DYNAMIC NMR-STUDIES OF THE RESTRICTED ROTATION OF THIOPHENES (TH) AND SELENOPHENES (SELN) IN THE CR(CO)3(ETA-5-TH) AND CR(CO)3(ETA-5-SELN) COMPLEXES SO ORGANOMETALLICS LA English DT Article ID TRANSITION-METAL COMPLEXES; SLOWED TRIPODAL ROTATION; CHROMIUM TRICARBONYL COMPLEXES; SULFUR-COORDINATED THIOPHENES; NUCLEAR MAGNETIC-RESONANCE; PROXIMAL ETHYL GROUPS; S BOND-CLEAVAGE; HYDRODESULFURIZATION CATALYSTS; C-13 NMR; X-RAY AB The reaction of Cr(CO)6 with thiophenes (Th) and selenophenes (Seln) produced Cr(CO)3-(eta5-Th) (Th = T, 2-MeT, 2-EtT, 3-MeT, 2,5-Me2T, and Me4T) and Cr(CO)3(eta5-Seln) (Seln = Sel, 2-MeSel, and 2,5-Me2Sel). Variable-temperature C-13 NMR spectra of these complexes in dimethyl ether indicated that there is restricted rotation about the Cr-Th and -Seln bonds. Band shape analyses of the C-13 NMR spectra using DNMR5 gave activation parameters for ring rotation. Activation enthalpies (DELTAH(double dagger), kcal/mol) for these complexes increase in the following order: T (6.2), 3-MeT (6.5), 2-EtT (6.9), 2-MeT (7.1), Me4T (7.4), 2,5-Me2T (7.7), Sel (7.8), 2-MeSel (8.4), and 2,5-Me2Sel (9.0). In general, alkyl substitution increases DELTAH(double dagger) and a-substitution leads to a larger DELTAH(double dagger) than beta-substitution. Substitution of the S heteroatom by Se also increases DELTAH(double dagger). These results are discussed in terms of the relative electron densities on the heteroatom and the diene fragment, which were estimated using extended Huckel molecular orbital (EHMO) calculations. The structure of Cr(CO)3(eta5-2,5-Me2T) was established by a single crystal X-ray diffraction study. The rotational barriers for these complexes are larger than those of Cr(CO)3(eta6-arene) complexes presumably due to the strong interaction between the chromium and the heteroatom. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. NR 117 TC 24 Z9 24 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD MAY PY 1994 VL 13 IS 5 BP 1821 EP 1831 DI 10.1021/om00017a045 PG 11 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA NL713 UT WOS:A1994NL71300045 ER PT J AU ZHU, ZL ESPENSON, JH AF ZHU, ZL ESPENSON, JH TI REACTIVITY OF A 17E ORGANOMETALLIC RADICAL IN AQUEOUS-SOLUTION SO ORGANOMETALLICS LA English DT Article ID LASER FLASH-PHOTOLYSIS; ELECTRON-TRANSFER; PHOTOCHEMISTRY; COMPLEXES; 17-ELECTRON; GENERATION; MECHANISM; KINETICS; HYDROGENATION; TUNGSTEN AB Laser flash photolysis of [(C5H4CO2-)W(CO)3]2 in aqueous solution at 460-532 nm induces homolysis of the metal-metal bond with formation of the 17e radical (C5H4CO2-)W(CO)3. The rate constant for its dimerization is 3.0 X 10(9) L mol-1 s-1 at 23-degrees-C. The radical reacts with haloacetate ions, pseudohalo- and halometal complexes by atom transfer. The reactivity trend is normal (RI > RBr > RCl). The reaction between this radical with t-BuOOH in water occurs similarly with a rate constant of 1.37 x 10(6) L mol-1 s-1. For electron-transfer reactions, the radical acts as both reductant and oxidant. It oxidizes tetramethylphenylenediamine to TMPD.+ in aqueous solution with a rate constant of 1.49 X 10(7) mol-1 s-1. The radical reduces MV2+ and Fe(CN)63- to MV.+ and Fe(CN)64- with rate constants of 2.0 x 10(6) and 6.06 X 10(7) L mol-1 s-1, respectively. The phosphine Ph2PPhSO3Na accelerates the reaction of the radical with MV2+ very mildly. This may bear on the question of whether the tungsten-phosphine adduct is a species with 19 valence electrons, a slipped cyclopentadienyl ring, or a phosphoranyl radical. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 31 TC 8 Z9 8 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0276-7333 J9 ORGANOMETALLICS JI Organometallics PD MAY PY 1994 VL 13 IS 5 BP 1893 EP 1898 DI 10.1021/om00017a053 PG 6 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA NL713 UT WOS:A1994NL71300053 ER PT J AU JONES, MT PLASSMANN, PE AF JONES, MT PLASSMANN, PE TI SCALABLE ITERATIVE SOLUTION OF SPARSE LINEAR-SYSTEMS SO PARALLEL COMPUTING LA English DT Article DE CONJUGATE GRADIENT METHODS; DISTRIBUTED-MEMORY COMPUTERS; GRAPH COLORING HEURISTICS; INCOMPLETE CHOLESKY; PARALLEL ALGORITHMS; SPARSE MATRICES ID GRAPH AB The efficiency of a parallel implementation of the conjugate gradient method preconditioned by an incomplete Cholesky factorization can very dramatically depending on the column ordering chosen. One method to minimize the number of major parallel steps is to choose an ordering based on a coloring of the symmetric graph representing the nonzero adjacency structure of the matrix. In this paper, we compare the performance of the preconditioned conjugate gradient method using these coloring orderings with a number of standard orderings on matrices arising from finite element models. Because optimal colorings for these systems may not be known a priori, we employ a graph coloring heuristic to obtain consistent colorings. Based on lower bounds obtained from the local structure of these systems, we find that the colorings determined by the heuristic are nearly optimal. For these problems, we find that the increase in parallelism afforded by the coloring-based orderings more than offsets any increase in the number of iterations required for the convergence of the conjugate gradient algorithm. We also demonstrate that the performance of this parellel preconditioner is scalable. We give results from the Intel iPSC/860 to support our claims. RP JONES, MT (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 27 TC 39 Z9 39 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8191 J9 PARALLEL COMPUT JI Parallel Comput. PD MAY PY 1994 VL 20 IS 5 BP 753 EP 773 DI 10.1016/0167-8191(94)90004-3 PG 21 WC Computer Science, Theory & Methods SC Computer Science GA NN546 UT WOS:A1994NN54600004 ER PT J AU BOIS, FY TOZER, TN HAUCK, WW CHEN, ML PATNAIK, R WILLIAMS, RL AF BOIS, FY TOZER, TN HAUCK, WW CHEN, ML PATNAIK, R WILLIAMS, RL TI BIOEQUIVALENCE - PERFORMANCE OF SEVERAL MEASURES OF EXTENT OF ABSORPTION SO PHARMACEUTICAL RESEARCH LA English DT Note DE PHARMACOKINETICS; BIOEQUIVALENCE; EXTENT OF ABSORPTION; POWER ANALYSIS AB The determination of the area under the concentration-time curve (AUC) is the method most commonly used by regulatory agencies to assess extent of drug absorption after single-dose administration of oral products. Using simulations, several approaches toward measuring the actual area, in whole or part, were tested. In addition, the performance of the peak concentration (C-max), usually taken as a measure of the rate of absorption was assessed evaluating extent. Model scenarios for drugs with typical mean characteristics and statistical distributions were investigated. Using different kinetic models of disposition, the time course of the drug concentration in plasma was simulated. Intraindividual and interindividual variability and assay error were modeled using Monte Carlo techniques. The accuracy, precision, and ease of use of the various measures of extent were evaluated, and statistical power analyses were performed. Among the measures tested, the most reliable were the AUC computed up to the time of the last quantifiable concentration, without extrapolation, and C-max. However, being also sensitive to rate, C-max as a measure of extent is of limited potential. C1 UNIV CALIF SAN FRANCISCO,SCH PHARM,SAN FRANCISCO,CA 94143. UNIV CALIF SAN FRANCISCO,DEPT EPIDEMIOL & BIOSTAT,SAN FRANCISCO,CA 94143. US FDA,CTR DRUG EVALUAT & RES,OFF GENER DRUGS,ROCKVILLE,MD 20855. RP BOIS, FY (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,INDOOR ENVIRONM PROGRAM,MAIL STOP 90-3058,BERKELEY,CA 94720, USA. RI Bois, Frederic/E-9241-2012 OI Bois, Frederic/0000-0002-4154-0391 FU PHS HHS [224-91-3007] NR 6 TC 47 Z9 47 U1 1 U2 3 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 SN 0724-8741 J9 PHARMACEUT RES JI Pharm. Res. PD MAY PY 1994 VL 11 IS 5 BP 715 EP 722 DI 10.1023/A:1018932430733 PG 8 WC Chemistry, Multidisciplinary; Pharmacology & Pharmacy SC Chemistry; Pharmacology & Pharmacy GA NJ623 UT WOS:A1994NJ62300017 PM 8058642 ER PT J AU ROSENBACHBELKIN, V SCHERZ, A MICHALSKI, TJ SCHIFFER, M NORRIS, J AF ROSENBACHBELKIN, V SCHERZ, A MICHALSKI, TJ SCHIFFER, M NORRIS, J TI THE EFFECT OF PERIPHERAL SUBSTITUTION ON THE BATHOCHROMIC SHIFT OF THE Q(Y) TRANSITION OF BACTERIOCHLOROPHYLL DIMERS - IN-VITRO MODELS OF THE PROTEIN EFFECT ON THE SPECTRUM OF PIGMENT CENTERS IN THE LIGHT-HARVESTING COMPLEXES SO PHOTOCHEMISTRY AND PHOTOBIOLOGY LA English DT Article ID PHOTOSYNTHETIC REACTION CENTER; RHODOPSEUDOMONAS-VIRIDIS; RHODOBACTER-SPHAEROIDES; SPECTROSCOPIC PROPERTIES; BACTERIA; OLIGOMERS; SUBUNITS; P-860 AB The effect of chemical modifications in the side groups of the isocyclic ring V on the formation, optical absorption and circular dichroism of bacteriochlorophyll (Bchl) dimers was examined in a mixture of formamide and water containing Triton X-100 and variable amounts of pyridine. Substitution of the carbomethoxy group in the C13(2) position with a hydrogen atom, had no effect on the dimerization constant but increased the shift of the Q(y) transition by 1000 cm(-1) with respect to the native Bchl. Substitution of the C13 hydrogen atom with OH decreased the shift of the Q(y) transition by 400 cm(-1) The similarity between the spectra of the modified Bchl dimers and Bchl dimers in vivo indicates that protein binding to the side groups at Bchl dimers may profoundly affect the energy of their Q(y) transition but have minor effects on the Q(y) transitions of the monomeric Bchl. C1 WEIZMANN INST SCI,DEPT BIOCHEM,IL-76100 REHOVOT,ISRAEL. ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439. ARGONNE NATL LAB,DIV BIOL ENVIRONM & MED,ARGONNE,IL 60439. NR 26 TC 0 Z9 0 U1 1 U2 1 PU AMER SOC PHOTOBIOLOGY PI AUGUSTA PA BIOTECH PARK, 1021 15TH ST, SUITE 9, AUGUSTA, GA 30901-3158 SN 0031-8655 J9 PHOTOCHEM PHOTOBIOL JI Photochem. Photobiol. PD MAY PY 1994 VL 59 IS 5 BP 579 EP 583 DI 10.1111/j.1751-1097.1994.tb02987.x PG 5 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA NN888 UT WOS:A1994NN88800014 ER PT J AU GLAZER, AN GINDT, YM CHAN, CF SAUER, K AF GLAZER, AN GINDT, YM CHAN, CF SAUER, K TI SELECTIVE DISRUPTION OF ENERGY-FLOW FROM PHYCOBILISOMES TO PHOTOSYSTEM-I SO PHOTOSYNTHESIS RESEARCH LA English DT Article DE CYANOBACTERIA; EXCITATION ENERGY TRANSFER; EPR; FLUORESCENCE; SULFHYDRYL MODIFICATION ID BLUE-GREEN-ALGAE; SYNECHOCOCCUS-SP; MASTIGOCLADUS-LAMINOSUS; PORPHYRIDIUM-CRUENTUM; ANACYSTIS-NIDULANS; C-PHYCOCYANIN; CYANOBACTERIUM; ORGANIZATION; POLYPEPTIDE; PROTEINS AB Efficient production of ATP and NADPH by the 'light' reactions of oxygen-evolving photosynthesis demands continuous adjustment of transfer of absorbed light energy from antenna complexes to Photosystem I (PS I) and II (PS II) reaction center complexes in response to changes in light quality. Treatment of intact cyanobacterial cells with N-ethylmaleimide appears to disrupt energy transfer from phycobilisomes to Photosystem I (PS I). Energy transfer from phycobilisomes to Photosystem II (PS II) is unperturbed. Spectroscopic analysis indicates that the individual complexes (phycobilisomes, PS II, PS I) remain functionally intact under these conditions. The results are consistent with the presence of connections between phycobiliproteins and both PS II and PS I, but they do not support the existence of direct contacts between the two photosystems. C1 UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,DIV STRUCT BIOL,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. RP GLAZER, AN (reprint author), UNIV CALIF BERKELEY,DEPT MOLEC & CELL BIOL,229 STANLEY HALL,BERKELEY,CA 94720, USA. NR 27 TC 36 Z9 38 U1 1 U2 3 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0166-8595 J9 PHOTOSYNTH RES JI Photosynth. Res. PD MAY PY 1994 VL 40 IS 2 BP 167 EP 173 DI 10.1007/BF00019333 PG 7 WC Plant Sciences SC Plant Sciences GA NZ906 UT WOS:A1994NZ90600003 PM 24311285 ER PT J AU XIAO, YG LI, JW YIN, B ZHAO, ZX FINNEMORE, DK VERHOEVEN, JD AF XIAO, YG LI, JW YIN, B ZHAO, ZX FINNEMORE, DK VERHOEVEN, JD TI IRREVERSIBILITY LINES IN CU-NB IN-SITU COMPOSITES SO PHYSICA C LA English DT Article ID HIGH-TC SUPERCONDUCTORS; TWO-DIMENSIONAL SUPERCONDUCTORS; VORTEX-GLASS SUPERCONDUCTIVITY; SINGLE-CRYSTAL YBA2CU3O7; FLUX-LATTICE; PHASE-TRANSITIONS; OXIDE SUPERCONDUCTORS; THERMAL FLUCTUATIONS; THICKNESS DEPENDENCE; ACTIVATION-ENERGIES AB The irreversibility lines in Cu-Nb in-situ formed composites have been investigated by DC magnetization measurements. Extended reversible regions are clearly identified in the H- T phase plane. The melting theory of the vortex lattice is found to describe the observed irreversibility lines well for all the three samples, whereas the flux-creep picture is also applicable for the thinnest one, due possibly to the suppression of the irreversibility line to lower temperatures at which pinning and flux creep are more important. The suppression of the irreversibility line with the reduced rolling thickness of the sample has also been discussed within the contexts of several theoretical models. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT MAT SCI ENGN,AMES,IA 50011. RP XIAO, YG (reprint author), CHINESE ACAD SCI,INST PHYS,NATL LAB SUPERCOND,BEIJING 100080,PEOPLES R CHINA. NR 49 TC 2 Z9 2 U1 1 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 1994 VL 224 IS 3-4 BP 240 EP 246 DI 10.1016/0921-4534(94)90260-7 PG 7 WC Physics, Applied SC Physics GA NK193 UT WOS:A1994NK19300006 ER PT J AU FEENSTRA, R LI, X KANAI, M KAWAI, T KAWAI, S BUDAI, JD JONES, EC SUN, YR THOMPSON, JR PENNYCOOK, SJ CHRISTEN, DK AF FEENSTRA, R LI, X KANAI, M KAWAI, T KAWAI, S BUDAI, JD JONES, EC SUN, YR THOMPSON, JR PENNYCOOK, SJ CHRISTEN, DK TI ELECTRON-DOPED AND HOLE-DOPED INFINITE-LAYER SR(1-X)CUO(2-DELTA) FILMS GROWN BY LASER MOLECULAR-BEAM EPITAXY SO PHYSICA C LA English DT Article ID CU-O SYSTEM; CRYSTAL-CHEMISTRY; THIN-FILMS; SUPERCONDUCTIVITY; OXIDES C1 OSAKA UNIV,INST SCI & IND RES,IBARAKI,OSAKA 567,JAPAN. UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. RP FEENSTRA, R (reprint author), OAK RIDGE NATL LAB,DIV SOLID STATE,POB 2008,OAK RIDGE,TN 37831, USA. RI Budai, John/R-9276-2016; OI Budai, John/0000-0002-7444-1306; Kanai, Masaki/0000-0002-0673-1512 NR 34 TC 24 Z9 24 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAY 1 PY 1994 VL 224 IS 3-4 BP 300 EP 316 DI 10.1016/0921-4534(94)90267-4 PG 17 WC Physics, Applied SC Physics GA NK193 UT WOS:A1994NK19300013 ER PT J AU ELLIOTT, S BEIERSDORFER, P NILSEN, J AF ELLIOTT, S BEIERSDORFER, P NILSEN, J TI MEASUREMENTS OF 3D-5F AND 3D-6F TRANSITION ENERGIES IN NICKEL-LIKE IONS FOR RESONANT PHOTOPUMPING BY HELIUM-LIKE IONS SO PHYSICA SCRIPTA LA English DT Article ID X-RAY LASER; ISOELECTRONIC SEQUENCE AB The 3d-5f and 3d-6f transition energies of several Ni-like ions were measured to study their suitability for use in an X-ray laser scheme that uses He-like K-shell transitions for resonant photopumping. Specifically, 19 transitions in Ag19+, Sn22+, Pr31+, Gd36+, Yb42+, Ta45+, Ir49+, Th62+ and U64+ were measured and compared to 2p-1s transitions in F7+, Ne8+, Si12+, S14+, Cl15+, Ar16+, Ti20+ and V21+. The best resonance found was for the F He-like 2P-1(1)-1S-1(0) transition pumping the Ag Ni-like 3d3/2-6f5/2 transition at 737.6 eV. The energy difference of 0.14 (24) eV corresponds to a 190-ppm resonance. An energy shift between the theoretical and measured energies of 3d5/2-6f7/2 transitions is confirmed by the present measurements; a similar effect is also observed in the 3d3/2-5f5/2, 3d5/2-5f7/2 and 3d3/2-6f5/2 transitions. RP ELLIOTT, S (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 21 TC 9 Z9 9 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PD MAY PY 1994 VL 49 IS 5 BP 556 EP 560 DI 10.1088/0031-8949/49/5/009 PG 5 WC Physics, Multidisciplinary SC Physics GA NJ503 UT WOS:A1994NJ50300009 ER PT J AU NILSEN, J SCOFIELD, JH AF NILSEN, J SCOFIELD, JH TI WAVELENGTHS OF NEON-LIKE 3P-]3S X-RAY LASER TRANSITIONS SO PHYSICA SCRIPTA LA English DT Article ID BEAM-FOIL; SOLAR-FLARES; 3P-3D TRANSITIONS; 3D CONFIGURATIONS; SPECTRAL-LINES; FE-XVII; NI-XIX; AR-IX; 3S-3P; IONS AB This paper presents the wavelengths of the neon-like 3p --> 3s laser lines which have been observed in both lasing and nonlasing plasmas and compares the experimental wavelengths with relativistic multi-configuration Hartree-Fock calculations in order to estimate the wavelengths for these lines in all neon-like ions between S6+ and Xe44+. The seven 3p --> 3s transitions which have been observed to lase in some neon-like ions are considered in this work. RP NILSEN, J (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 43 TC 43 Z9 43 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PD MAY PY 1994 VL 49 IS 5 BP 588 EP 591 DI 10.1088/0031-8949/49/5/015 PG 4 WC Physics, Multidisciplinary SC Physics GA NJ503 UT WOS:A1994NJ50300015 ER PT J AU SCHONFELD, B ICE, GE SPARKS, CJ HAUBOLD, HG SCHWEIKA, W SHAFFER, LB AF SCHONFELD, B ICE, GE SPARKS, CJ HAUBOLD, HG SCHWEIKA, W SHAFFER, LB TI X-RAY STUDY OF DIFFUSE-SCATTERING IN NI-20 AT-PERCENT CR SO PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS LA English DT Article ID SHORT-RANGE ORDER; NEUTRON-SCATTERING; ATOMIC INTERACTION; SINGLE-CRYSTALS; MONTE-CARLO; NI-MO; ALLOYS; DISPLACEMENTS; PHASE AB A single crystal of Ni-20 at% Cr aged at 744 K for 480 h, similar to the case of a previous neutron scattering experiment, is investigated by diffuse X-ray scattering using X-rays at three different wavelengths, lambda = 0.2075 nm (5975 eV), 0.1489 nm (8327.2 eV), and 0.1531 nm (8097 eV). The short-range order and displacement scattering are separated based on the 3lambda method recently introduced as well as on the Georgopoulos-Cohen method. Both evaluation schemes yield similar Warren-Cowley short-range order parameters with less agreement in the individual static atomic displacements. The nearest-neighbor displacement obtained by the 3lambda method for Ni-Cr pairs, is consistent with a simple phenomenological model in which the Cr atoms expand the Ni lattice in a short-range ordered alloy. Effective pair interactions calculated from model crystals using the inverse Monte Carlo method are found to be larger than previously deduced from neutron scattering experiments. If these pair interactions are used in Monte Carlo simulations to calculate the transition temperature T0 of Ni2Cr, T0 is underestimated compared with direct experimental findings. C1 OAK RIDGE NATL LAB, DIV MET & CERAM, OAK RIDGE, TN 37831 USA. FORSCHUNGSZENTRUM JULICH, INST FESTKORPERFORSCH, D-52428 JULICH, GERMANY. ANDERSON UNIV, DEPT PHYS, ANDERSON, IN 46012 USA. RP SCHONFELD, B (reprint author), EIDGENOSS TECH HSCH ZURICH, INST ANGEW PHYS, CH-8093 ZURICH, SWITZERLAND. NR 32 TC 22 Z9 22 U1 1 U2 12 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA PO BOX 10 11 61, D-69451 WEINHEIM, GERMANY SN 0370-1972 J9 PHYS STATUS SOLIDI B JI Phys. Status Solidi B-Basic Solid State Phys. PD MAY PY 1994 VL 183 IS 1 BP 79 EP 95 DI 10.1002/pssb.2221830105 PG 17 WC Physics, Condensed Matter SC Physics GA NP923 UT WOS:A1994NP92300004 ER PT J AU STAPP, HP AF STAPP, HP TI STRONG VERSIONS OF BELL THEOREM SO PHYSICAL REVIEW A LA English DT Article AB Technical aspects of a recently constructed strong version of Bell's theorem are discussed. The theorem assumes neither hidden variables nor factorization, and neither determinism nor counterfactual definiteness. It deals directly with logical connections. Hence its relationship with modal logic needs to be described. It is shown that the proof can be embedded in an orthodox modal logic, and hence its compatibility with modal logic assured, but that this embedding weakens the theorem by introducing as added assumptions the conventionalities of the particular modal logic that is adopted. This weakening is avoided in the recent proof by using directly the set-theoretic conditions entailed by the locality assumption. RP STAPP, HP (reprint author), LAWRENCE BERKELEY LAB,DIV PHYS,THEORET PHYS GRP,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 6 TC 6 Z9 6 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP 3182 EP 3187 DI 10.1103/PhysRevA.49.3182 PN A PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL385 UT WOS:A1994NL38500011 ER PT J AU KWIAT, PG EBERHARD, PH STEINBERG, AM CHIAO, RY AF KWIAT, PG EBERHARD, PH STEINBERG, AM CHIAO, RY TI PROPOSAL FOR A LOOPHOLE-FREE BELL INEQUALITY EXPERIMENT SO PHYSICAL REVIEW A LA English DT Article ID TIME; INTERFERENCE; VIOLATION; COHERENCE; THEOREM; PHOTONS; STATES; TESTS; INTERFEROMETRY; CONVERSION AB The nonlocality inherent in quantum mechanics has been tested experimentally, but the nonlocal interpretation of all the relevant experiments can be challenged. All past tests of Bell's inequalities have required supplementary assumptions, without which the experimental results satisfy the inequalities, in agreement with the notion of local realism. There are basically three loopholes that need to be closed; neither the cascade sources nor the parametric down-conversion sources of correlation photons used to date are capable of closing all of them, even if the detectors used had been 100% efficient. We propose a two-crystal down-conversion source, relying on type-II collinear phase matching, which should permit a violation of Bell's inequalities without the need for supplementary assumptions. As the source can produce a true singletlike state, it is also relevant for quantum cryptographic applications. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP KWIAT, PG (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Steinberg, Aephraim/C-3226-2008 NR 40 TC 119 Z9 119 U1 1 U2 11 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP 3209 EP 3220 DI 10.1103/PhysRevA.49.3209 PN A PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL385 UT WOS:A1994NL38500015 ER PT J AU SIMIONOVICI, A BIRKETT, BB MARRUS, R CHARLES, P INDELICATO, P DIETRICH, DD FINLAYSON, K AF SIMIONOVICI, A BIRKETT, BB MARRUS, R CHARLES, P INDELICATO, P DIETRICH, DD FINLAYSON, K TI CASCADE-FREE DOPPLER-TUNED PRECISION-MEASUREMENT OF THE LIFETIME OF THE 2 S-3(1) STATE IN HE-LIKE NIOBIUM (NB-93(39+) SO PHYSICAL REVIEW A LA English DT Article ID X-RAY SPECTROMETER; HELIUMLIKE IONS; 23S1 STATE AB The lifetime of the 2 S-3(1) state in He-like niobium (Nb39+) has been precisely determined with a beam-foil time-of-flight technique. The isotope Nb-93 (I = 9/2) was chosen in order to minimize cascade effects through hyperfine quenching of the primary feeding state. Further precision was obtained by removing blends with a Doppler-tuned transmission filter. Other cascade contributions were analyzed and found to be negligible. The result is 45.45 (16) X 10(-12) sec and represents increased sensitivity to corrections of O(Zalpha)2 in the Zalpha-series expansion for the lifetime by a factor of 5. C1 UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. UNIV PARIS 06,INST RADIUM,LPAN,F-75252 PARIS 05,FRANCE. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP SIMIONOVICI, A (reprint author), CENG,LAGRIPPA,BOITE POSTALE 85X,GRENOBLE,FRANCE. RI Indelicato, Paul/D-7636-2011 OI Indelicato, Paul/0000-0003-4668-8958 NR 20 TC 12 Z9 12 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP 3553 EP 3556 DI 10.1103/PhysRevA.49.3553 PN A PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL385 UT WOS:A1994NL38500050 ER PT J AU BASAVARAJU, G KANE, PP KISSEL, LD PRATT, RH AF BASAVARAJU, G KANE, PP KISSEL, LD PRATT, RH TI ELASTIC-SCATTERING OF 81-KEV GAMMA-RAYS SO PHYSICAL REVIEW A LA English DT Article ID X-RAYS; ANOMALOUS DISPERSION; INELASTIC-SCATTERING; RAYLEIGH-SCATTERING; COHERENT SCATTERING; KEV PHOTONS; EDGE; ZN; PB AB A high-purity germanium detector was used to determine differential cross sections for the elastic scattering of 81-keV gamma rays by aluminum, nickel, tantalum, gold, and lead through angles of 60-degrees, 90-degrees, 120-degrees, and 133. The atomic Rayleigh scattering amplitudes were obtained in the independent-particle approximation by calculations of modified relativistic form factors (MF's), a combination of MF's and angle-independent ''anomalous'' scattering factors (ASF's), and the relativistic second-order S matrix. Most experimental cross sections for gold and lead are slightly smaller than the calculations in the S matrix or the MF-ASF approaches, the differences being larger in the latter case. The calculated cross sections based on MF's are enormously larger than these values. The tantalum data are in good agreement with S-matrix calculations. The data for Al show agreement with the different calculations, which differ by less than about 6%. C1 LAWRENCE LIVERMORE NATL LAB,COMPUTAT PHYS GRP L-59,LIVERMORE,CA 94550. UNIV PITTSBURGH,DEPT PHYS & ASTRON,PITTSBURGH,PA 15260. RP BASAVARAJU, G (reprint author), INDIAN INST TECHNOL,DEPT PHYS,BOMBAY 400076,INDIA. NR 31 TC 26 Z9 26 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP 3664 EP 3672 DI 10.1103/PhysRevA.49.3664 PN A PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL385 UT WOS:A1994NL38500061 ER PT J AU FONTES, CJ SAMPSON, DH ZHANG, HL AF FONTES, CJ SAMPSON, DH ZHANG, HL TI USE OF THE FACTORIZED FORM FOR THE COLLISION STRENGTH IN EXPLORATION OF THE EFFECT OF THE GENERALIZED BREIT INTERACTION SO PHYSICAL REVIEW A LA English DT Article ID HIGHLY CHARGED IONS; ELECTRON-IMPACT EXCITATION; EQUAL-TO 92; OSCILLATOR-STRENGTHS; 8-LESS-THAN-OR-EQUAL-TO-Z-LESS-THAN-OR-EQUAL-TO-92; PROGRAM AB Expressions are given for the convenient factorized form [Bar-Shalom, Klapisch, and Oreg, Phys. Rev. A 38, 1773 (1988)] for the collision strength with inclusion of the generalized Breit interaction. This is used to explore further the importance of the inclusion of the generalized Breit interaction in calculating electron-impact excitation cross sections or collision strengths, by considering the inner-shell excitation of Be-like uranium and the n = 2 to n = 3 transitions in neonlike xenon and uranium. C1 PENN STATE UNIV,DEPT ASTRON & ASTROPHYS,UNIV PK,PA 16802. RP FONTES, CJ (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 24 TC 12 Z9 12 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP 3704 EP 3711 DI 10.1103/PhysRevA.49.3704 PN A PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL385 UT WOS:A1994NL38500065 ER PT J AU HINO, K NAGASE, M OKAMOTO, H MORISHITA, T MATSUZAWA, M KIMURA, M AF HINO, K NAGASE, M OKAMOTO, H MORISHITA, T MATSUZAWA, M KIMURA, M TI DOUBLE-ELECTRON EXCITATION OF H- BY FAST PROTON AND ANTIPROTON IMPACT SO PHYSICAL REVIEW A LA English DT Article ID FAST-ION IMPACT; HYPERSPHERICAL APPROACH; BORN APPROXIMATION; EXCITED-STATES; BOUNDARY-CONDITIONS; ATOM COLLISIONS; HELIUM; CAPTURE; IONIZATION; MANIFOLDS AB A theoretical investigation is carried out for double-electron excitation processes of H- induced by proton and antiproton impact at the energy of 1.5 MeV. Excitation cross sections to the 2s2 S-1(e), 2s2p P-1(o), and 2p2 1D(e) states are calculated by using the plane-wave Born approximation, the distorted-wave Born approximation, and the close-coupling method. Wave functions of H- are generated employing the hyperspherical coordinate method. It is shown that the low-lying continuum 1 skp P-1(o) is identified as an important intermediate state in the double-electron excitation process to the 2p2 1D(e) state. We have also evaluated the ejected-electron spectra from the 2s2p P-1(o) shape-resonance state. It is found that its spectral shape is close to the observed line profile of the photodetachment of H- since the excitation mechanism to this state is mostly dominated by the optically allowed transition at the projectile energy concerned here. C1 RIKEN,ATOM PHYS LAB,WAKO,SAITAMA 35101,JAPAN. UNIV ELECTROCOMMUN,DEPT APPL PHYS & CHEM,CHOFU,TOKYO 182,JAPAN. ARGONNE NATL LAB,ARGONNE,IL 60439. RICE UNIV,DEPT PHYS,HOUSTON,TX 77251. UNIV TENNESSEE,DEPT PHYS & ASTRON,200 S COLL,KNOXVILLE,TN 37996. NR 39 TC 4 Z9 4 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP 3753 EP 3760 DI 10.1103/PhysRevA.49.3753 PN A PG 8 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL385 UT WOS:A1994NL38500069 ER PT J AU HUANG, JY SHEN, YR AF HUANG, JY SHEN, YR TI THEORY OF DOUBLY RESONANT INFRARED-VISIBLE SUM-FREQUENCY AND DIFFERENCE-FREQUENCY-GENERATION FROM ADSORBED MOLECULES SO PHYSICAL REVIEW A LA English DT Article ID OPTICAL 2ND-HARMONIC GENERATION; POLYATOMIC-MOLECULES; RAMAN-SCATTERING; CONDENSED PHASES; METAL-SURFACE; PHOTON-ECHOES; SPECTROSCOPY; VIBRATION; RELAXATION; H/SI(111) AB We theoretically analyze doubly resonant infrared-visible sum-frequency (DR IVSFG) and difference-frequency generation (DR IVDFG) from a monolayer of adsorbates at an interface. our calculated results with a model molecule indicate that the resonant amplitude of nonlinear optical susceptibility of DR IVDFG and DR IVSFG processes conveys information about the electron-vibration coupling in adsorbates. Moreover, owing to a dephasing-rephasing procedure involved, DR IVDFG can also be developed into a sensitive probe for investigating the coherent phase relaxation process in adsorbed molecules without the complication of inhomogeneous broadening. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. RP HUANG, JY (reprint author), CHIAO TUNG UNIV,INST ELECTROOPT ENGN,HSINCHU,TAIWAN. NR 34 TC 47 Z9 47 U1 1 U2 10 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP 3973 EP 3981 DI 10.1103/PhysRevA.49.3973 PN B PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL386 UT WOS:A1994NL38600019 ER PT J AU STAPP, HP AF STAPP, HP TI STAPPS ALGEBRAIC ARGUMENT FOR NONLOCALITY - REPLY SO PHYSICAL REVIEW A LA English DT Letter ID BELLS THEOREM; QUANTUM AB The logical structure of my recently proved nonlocality theorem [Phys. Rev. A 46, 6860 (1992)] is examined from the perspective of the theory counterfactual conditionals. It is shown in detail why the argument of Dickson and Clifton [preceding Comment, Phys. Rev. A 49, 4259 (1994)] does not substantiate their claim. RP STAPP, HP (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 14 TC 7 Z9 7 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP 4257 EP 4260 DI 10.1103/PhysRevA.49.4257 PN B PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL386 UT WOS:A1994NL38600056 ER PT J AU CRAWFORD, OH AF CRAWFORD, OH TI MECHANISM FOR FRAGMENTATION OF MOLECULES BY POSITRON-ANNIHILATION SO PHYSICAL REVIEW A LA English DT Note ID IONIZATION MASS-SPECTROMETRY; ORGANIC-MOLECULES; SPECTRA AB A mechanism is proposed for fragmentation resulting from positron-induced ionization of polyatomic molecules at energies below the threshold for producing positronium. The mechanism is supported by calculation, and by comparison with experimental data. RP CRAWFORD, OH (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 21 TC 34 Z9 34 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP R3147 EP R3151 PN A PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL385 UT WOS:A1994NL38500002 ER PT J AU XU, J HULETT, LD LEWIS, TA DONOHUE, DL MCLUCKEY, SA CRAWFORD, OH AF XU, J HULETT, LD LEWIS, TA DONOHUE, DL MCLUCKEY, SA CRAWFORD, OH TI INTERNAL ENERGY DEPOSITION INTO MOLECULES UPON POSITRON-ELECTRON ANNIHILATION SO PHYSICAL REVIEW A LA English DT Note ID POSITRON AB The dissociative ionization of organic molecules, induced by positrons having energies below the positronium threshold (0.5-3 eV), has been studied. Cross sections for the ionization-fragmentation processes increase as positron energies decrease. The data reveal that the energy required for dissociative ionization is supplied by the annihilation process, and that fragmentation occurs by breakage of C-C single bonds in preference to double and triple bonds. RP XU, J (reprint author), OAK RIDGE NATL LAB,POB 2008,OAK RIDGE,TN 37831, USA. RI McLuckey, Scott/B-2203-2009 OI McLuckey, Scott/0000-0002-1648-5570 NR 16 TC 33 Z9 33 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD MAY PY 1994 VL 49 IS 5 BP R3151 EP R3154 PN A PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NL385 UT WOS:A1994NL38500003 ER PT J AU ROSE, JH SHORE, HB AF ROSE, JH SHORE, HB TI ELASTIC-CONSTANTS OF THE TRANSITION-METALS FROM A UNIFORM ELECTRON-GAS SO PHYSICAL REVIEW B LA English DT Article ID IDEAL METALS AB The trends in the elastic constants of the simple and transition elemental cubic metals are explained in terms of a uniform electron-gas theory. Recently, the bonding energetics of elemental metals were systematized using a new uniform electron-gas model. Dubbed the ''ideal metal,'' this model stems from a physical interpretation of the process of cleaving the positive background, and posits that no forces act on the background in the uniform state. Previously, this new model was used to show that the cohesive energies of the elemental transition metals depend primarily on the bonding valence and the average electron density at the boundary of the unit cell. Here, we use a slight modification of the same model to show that the elastic constants of the elemental cubic metals depend primarily on the bonding valence, the density at the cell boundary, and the symmetry of the lattice. C1 SAN DIEGO STATE UNIV,DEPT PHYS,SAN DIEGO,CA 92182. RP ROSE, JH (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 16 TC 31 Z9 31 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 11588 EP 11601 DI 10.1103/PhysRevB.49.11588 PG 14 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300006 ER PT J AU LIBBERT, JL KELTON, KF GOLDMAN, AI YELON, WB AF LIBBERT, JL KELTON, KF GOLDMAN, AI YELON, WB TI STRUCTURAL DETERMINATION OF A 1/1 RATIONAL APPROXIMANT TO THE ICOSAHEDRAL PHASE IN TI-CR-SI ALLOYS SO PHYSICAL REVIEW B LA English DT Article ID DIFFUSE-SCATTERING; MN; QUASICRYSTAL; DIFFRACTION; SYMMETRY; CRYSTAL; ARCS AB We report the discovery and structural refinement of a large unit cell bcc crystalline phase in a Ti-Cr-Si alloy that is a 1/1 rational approximant to the icosahedral phase in that system. The crystal structure was determined from a Rietveld analysis of x-ray and neutron powder diffraction data. Our results demonstrate that this phase is closely related to the alpha(Al-Mn-Si) phase, which in turn, is closely related to the structure of the icosahedral phase in the Al-transition-metal alloys. The neutron data indicate that the structure contains a significant amount of oxygen located in the Mackay clusters. Partial ordering of this oxygen may provide an explanation for the localized diffuse scattering often observed in the i phase and related crystalline phases in Ti-transition-metal alloys. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. UNIV MISSOURI,COLUMBIA,MO 65211. RP LIBBERT, JL (reprint author), WASHINGTON UNIV,DEPT PHYS,ST LOUIS,MO 63130, USA. NR 20 TC 29 Z9 29 U1 1 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 11675 EP 11681 DI 10.1103/PhysRevB.49.11675 PG 7 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300014 ER PT J AU BAKER, DB CONRADI, MS NORBERG, RE BARNES, RG TORGESON, DR AF BAKER, DB CONRADI, MS NORBERG, RE BARNES, RG TORGESON, DR TI EXPLANATION OF THE HIGH-TEMPERATURE RELAXATION ANOMALY IN A METAL-HYDROGEN SYSTEM SO PHYSICAL REVIEW B LA English DT Article ID NUCLEAR-MAGNETIC-RESONANCE; SPIN-LATTICE-RELAXATION; DYNAMICAL EVIDENCE; TRANSITION-METALS; HYDRIDES; DIFFUSION; COMPLEXES AB The source of high-temperature anomalous spin relaxation in a specific metal-hydrogen system has been investigated. Proton spin-lattice relaxation rates R1 from 290 to 1025 K were compared for Nb0.5V0.5H0.36 and its 90% deuterided counterpart, Nb0.5V0.5(H0.1D0.9)0.36. A substantial reduction in the anomalous proton relaxation rate R1 is observed for the deuterided metal. Thus, the proton relaxation rates R1 are determined by proton-proton (or proton-deuteron) dipolar interactions in the anomalous regime, suggesting that H-2 (or HD) molecules are the source of the relaxation. Relaxation studies with overpressures of argon and xenon gas indicate that the anomalous relaxation of protons in the metal occurs via fast exchange with rapidly relaxing gas phase H-2 molecules. A small fraction of protons in the gas phase, consistent with the H-2 vapor pressure of the metal hydride, is adequate to explain our results. A model, based on experiment, is presented along with measurements of the proton R1 for pure H-2 and HD gas and gaseous mixtures of H-2 with Ar and H-2 with D2. The model quantitatively accounts for the isotope and rare-gas effects as well as the temperature dependence. Thus, in Nb0.5V0.5H0.36, the relaxation anomaly is proven not to be an intrinsic effect. C1 IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS,AMES,IA 50011. RP BAKER, DB (reprint author), WASHINGTON UNIV,DEPT PHYS 1105,ST LOUIS,MO 63130, USA. NR 39 TC 10 Z9 10 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 11773 EP 11782 DI 10.1103/PhysRevB.49.11773 PG 10 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300025 ER PT J AU MAGNOTTA, F COLLINS, GW MAPOLES, ER AF MAGNOTTA, F COLLINS, GW MAPOLES, ER TI OPTICAL-EMISSION FROM ELECTRONS IN SOLID DEUTERIUM-TRITIUM SO PHYSICAL REVIEW B LA English DT Article ID ABSORPTION; HYDROGEN AB We report an increase in an emission from solid deuterium tritium at 825 nm, while pumping an electron bubble transition centered at approximately 350 nm. This experiment implies unbound electrons cause the emission at 825 nm. We find this steady-state emission shifts 8 nm towards longer wavelengths upon increasing the temperature from 4.5 to 10 K. Finally, the same emission in pure solid T2 is shifted 3 nm towards longer wavelengths and contains a triplet structure similar to the triplet structure observed in absorption measurements of the IS to IP transition of electron bubbles. RP MAGNOTTA, F (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551, USA. NR 23 TC 3 Z9 3 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 11817 EP 11821 DI 10.1103/PhysRevB.49.11817 PG 5 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300031 ER PT J AU HIROTA, K SHIRANE, G GEHRING, PM MAJKRZAK, CF AF HIROTA, K SHIRANE, G GEHRING, PM MAJKRZAK, CF TI NEUTRON-SCATTERING STUDIES OF THE 2 MAGNETIC CORRELATION LENGTHS IN TERBIUM SO PHYSICAL REVIEW B LA English DT Article ID CRITICAL FLUCTUATIONS; SRTIO3; SCALES; PHASE; TB AB Extensive neutron-scattering experiments have been performed in order to characterized the nature of the two correlation lengths observed in Tb, a phenomenon common to Ho as well as SrTiO3. In the vicinity of the transition temperature, each of those crystals exhibits an anomalous two-component q profile in the critical scattering; the usual broad peak and an unexpected additional narrow peak. In order to clarify the spatial origin of the narrow component, the (0, 0, delta) magnetic satellite peak of Tb has been closely examined using a very narrow neutron beam realized by a high spatial resolution reflectometer at the National Institute of Standards and Technology, which can produce well-defined beam widths of 0.3 mm and less. The small scattering angle (theta almost-equal-to 1.35-degrees) and the narrow beam width result in an extraordinarily fine q and E resolution. As recently reported, we have confirmed that the intensity of the narrow component is enhanced near the edge of the crystal; it demonstrates that the major part is located within the near surface volume or ''skin'' of the crystal. A skin thickness of approximately 0.2 mm full width at half maximum (FWHM) is obtained by fitting the results to a model scatterer distribution which convolutes the beam profile. In contrast to the case of the central peak observed in SrTiO3, this unusual spatial distribution establishes the narrow component as a distinct entity in the critical fluctuations. We have shown that the narrow component possesses a different temperature dependence of delta from that of the broad one. Moreover, high E resolution scans show that the narrow component has a distinct energy width which is smaller than our resolution limit (approximately 2 mueV FWHM), and that it is essentially temperature independent. We believe that this quasistatic character of the narrow component is the important key to understanding its physical origin. C1 NATL INST STAND & TECHNOL,GAITHERSBURG,MD 20899. RP HIROTA, K (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. RI Hirota, Kazuma/C-6797-2008; OI Gehring, Peter/0000-0002-9236-2046 NR 22 TC 52 Z9 52 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 11967 EP 11978 DI 10.1103/PhysRevB.49.11967 PG 12 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300048 ER PT J AU RUPP, B AF RUPP, B TI CERIUM MOMENT COLLAPSE IN TERNARY SILICIDES CEPD2-XMNXSI2 (0-LESS-THAN-OR-EQUAL-TO-X-LESS-THAN-OR-EQUAL-TO-2) SO PHYSICAL REVIEW B LA English DT Note ID X-RAY-ABSORPTION; CE VALENCE; FINE-STRUCTURE; EDGE; ALLOYS AB Cerium L3 XANES (x-ray-absorption near-edge-structure) spectra were analyzed to separate Ce moment contributions and mixed valence (MV) in complex magnetic silicides CePd2-xMnxSi2 (0 less-than-or-equal-to x less-than-or-equal-to 2). The Ce valence mixing does not vary linearly with x, but increases rapidly for x greater-than-or-equal-to 1.5. The associated moment collapse correlates with pronounced deviations of the unit-cell volume from Vegard law and the onset of structural instability. Reorientation of [001] Mn 3d antiferromagnetic order for x < 2 appears to rapidly suppress the weak Ce valence mixing coexisting with antiferromagnetic order in CeMn2Si2. RP RUPP, B (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94551, USA. NR 11 TC 4 Z9 4 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 12278 EP 12280 DI 10.1103/PhysRevB.49.12278 PG 3 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300089 ER PT J AU ABRIKOSOV, AA GORKOV, LP AF ABRIKOSOV, AA GORKOV, LP TI THEORY OF IMPURE SUPERCONDUCTORS - ANDERSON VERSUS ABRIKOSOV AND GORKOV - COMMENT SO PHYSICAL REVIEW B LA English DT Letter AB A response is given to a criticism in a paper of Kim and Overhauser of an earlier work by Abrikosov and Gor'kov on superconductors with impurities. The criticism is based on a primitive misunderstanding of the nature of the attraction of electrons achieved by phonons. As it was explained by the present authors in several publications, there exists a complete equivalence of their results with the later work by Anderson. C1 FLORIDA STATE UNIV,NATL HIGH MAGNET FIELD LAB,TALLAHASSEE,FL 32306. LD LANDAU THEORET PHYS INST,MOSCOW,RUSSIA. RP ABRIKOSOV, AA (reprint author), ARGONNE NATL LAB,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 6 TC 18 Z9 18 U1 2 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 12337 EP 12338 DI 10.1103/PhysRevB.49.12337 PG 2 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300105 ER PT J AU WOLVERTON, C DEFONTAINE, D AF WOLVERTON, C DEFONTAINE, D TI SITE SUBSTITUTION OF TERNARY ADDITIONS TO NI3AL (GAMMA') FROM ELECTRONIC-STRUCTURE CALCULATIONS SO PHYSICAL REVIEW B LA English DT Note ID ALLOYING BEHAVIOR; OCCUPATION; DUCTILITY; STABILITY; SYSTEM; BORON; PHASE; PD AB A real-space, Green-function method is proposed to examine the electronic structure and site preference of substitutional ternary additions to Ni3Al (gamma') using the tight-binding method of linear muffin-tin orbitals (TB-LMTO). Pairs of atoms are embedded in a random Ni0.75Al0.25 medium (of approximately 1000 atoms), one-electron energies are obtained by performing recursion on the TB-LMTO Hamiltonian, and the effective pair interactions (EPI's) determined by configurational averaging. Depending on the relative values of the three EPI's, W(Ni-Al), W(Ni-X) and W(Al-X), the ternary addition may occupy either the Ni site or the Al site exclusively, or the site preference may be a function of alloy stoichiometry. The site-substitution behavior in both stoichiometric and non-stoichiometric Ni3Al alloys is computed for six ternary additions, X (X = Co,Cu,Zn,Rh,Pd,Si). The theoretical predictions are in excellent agreement with experimental data, where available. C1 UNIV CALIF BERKELEY, DEPT PHYS, BERKELEY, CA 94720 USA. UNIV CALIF BERKELEY, DEPT MAT SCI & MINERAL ENGN, BERKELEY, CA 94720 USA. LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. RI Wolverton, Christopher/B-7542-2009 NR 30 TC 16 Z9 16 U1 2 U2 12 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 12351 EP 12354 DI 10.1103/PhysRevB.49.12351 PG 4 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300110 ER PT J AU ZHANG, LZ CANRIGHT, G BARNES, T AF ZHANG, LZ CANRIGHT, G BARNES, T TI SIMULATING COMPLEX PROBLEMS WITH THE QUANTUM MONTE-CARLO METHOD SO PHYSICAL REVIEW B LA English DT Note ID 2 DIMENSIONS; SYSTEMS; FIELD; ALGORITHM; FERMIONS AB We describe a quantum Monte Carlo technique suitable for generically complex problems, such as systems coupled to external magnetic fields or anyons in two spatial dimensions. We find that the gauge plays a nontrivial role in the simulation, and that a judicious choice of gauge considerably reduces the statistical error. One may similarly reduce the statistical error in simulations of particles in external magnetic fields by arranging an approximate cancellation between the (gauge-dependent) phases of the statistical flux and the external magnetic flux. C1 OAK RIDGE NATL LAB, DIV SOLID STATE, OAK RIDGE, TN 37831 USA. OAK RIDGE NATL LAB, DIV PHYS, OAK RIDGE, TN 37831 USA. OAK RIDGE NATL LAB, CTR COMPUTAT INTENS PHYS, OAK RIDGE, TN 37831 USA. RP UNIV TENNESSEE, DEPT PHYS & ASTRON, KNOXVILLE, TN 37996 USA. NR 22 TC 1 Z9 1 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 12355 EP 12358 DI 10.1103/PhysRevB.49.12355 PG 4 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300111 ER PT J AU ALVES, S BOEKEMA, C HALIM, C LAM, JC WHANG, E COOKE, DW LEON, M AF ALVES, S BOEKEMA, C HALIM, C LAM, JC WHANG, E COOKE, DW LEON, M TI MUON-SPIN-ROTATION STUDY OF VORTEX STATES IN RBA2CU3O7 USING MAXIMUM-ENTROPY ANALYSIS SO PHYSICAL REVIEW B LA English DT Note ID MAGNETIC-FIELD PENETRATION; II SUPERCONDUCTORS; TC; CUPRATE; PHASE; DEPTH AB A maximum-entropy method has been applied to transverse-field muon-spin-rotation vortex data of RBa2Cu3O7 (R 1:2:3:7; R =Er, Gd, and Eu); this produces spectra representing estimates for the magnetic-field distributions. The information on the field distribution is of better quality than that resulting from Fourier transformation and curve fitting of the same data. Significant deviations from Abrikosov predictions have been observed for the estimated R 1:2:3:7 vortex-field distributions. Below 10 K, for Er 1:2:3:7 and Gd 1:2:3:7, the non-Abrikosov features appear to be influenced by the magnetism of the rare-earth layers. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP ALVES, S (reprint author), SAN JOSE STATE UNIV,DEPT PHYS,SAN JOSE,CA 95192, USA. NR 30 TC 9 Z9 9 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 17 BP 12396 EP 12399 DI 10.1103/PhysRevB.49.12396 PG 4 WC Physics, Condensed Matter SC Physics GA NL643 UT WOS:A1994NL64300122 ER PT J AU MORIARTY, JA AF MORIARTY, JA TI ANGULAR FORCES AND MELTING IN BCC TRANSITION-METALS - A CASE-STUDY OF MOLYBDENUM SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-DIFFRACTION; ALLOY MO-RE; INTERATOMIC POTENTIALS; THERMODYNAMIC PROPERTIES; MOLECULAR-DYNAMICS; PHASE-TRANSITIONS; REFRACTORY-METALS; PRESSURE; COMPRESSION; NIOBIUM AB Using multi-ion interatomic potentials derived from first-principles generalized pseudopotential theory (GPT) together with molecular-dynamics (MD) simulation, a detailed study of melting and related high-temperature solid and liquid properties in molybdenum has been performed. The energetics in such bec transition metals are dominated by d-state interactions that give rise to both many-body angular forces and enhanced electron-thermal contributions. The angular forces are accounted for in the GPT through explicit three- and four-ion potentials, v3 and v4, which in the present work are applied in analytic model-GPT (MGPT) form. With the MGPT potentials, ion-thermal melting in Mo has been investigated both mechanically, by cycling up and down through the observed MD melting point at constant volume, and thermodynamically, by calculating solid and liquid free energies. In the former approach, parallel MD simulations have also been done with a corresponding effective-pair potential v2eff in which the angular dependence Of v3 and v4 has been averaged. The multi-ion angular forces, which are essential to an accurate description of the bcc solid, are found to lower the dynamically observed melting point by about 1000 K. Above the melting transition, however, v2eff gives a reasonbly good account of the structure and thermal energy of the liquid and the accuracy of this description improves with increasing temperature. Both the multi-ion and effective pair potentials also permit a large amount of supercooling of the liquid before the onset of freezing. With v2eff a bcc structure is nucleated at freezing, while with the multi-ion potentials an amorphous glasslike structure is obtained, which appears to be related to the energetically competitive A 15 structure. In our second approach to melting, the multi-ion potentials have been used to obtain accurate solid and liquid free energies from quasiharmonic lattice dynamics and MD calculations of thermal energies and pressures. The resulting ion-thermal melting curve exactly overlaps the dynamically observed melting point, indicating that no superheating of the solid occurred in our MD simulations. To obtain a full melting curve, electron-thermal contributions to the solid and liquid free energies are added in terms of the density of electronic states at the Fermi level, rho(E(F)). Here the density of states for the solid has been calculated with the linear-muffin-tin-orbital method, while for the liquid tight-binding calculations have been used to justify a simple model. In the liquid rho(E(F)) is increased dramatically over the bcc solid, and the net effect of the electron-thermal contributions is to lower the calculated melting temperatures by about a factor of 2. A full melting curve to 2 Mbar has thereby been obtained and the calculated melting properties near zero pressure are in generally good agreement with experiment. RP LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94551 USA. NR 48 TC 111 Z9 111 U1 1 U2 16 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 18 BP 12431 EP 12445 DI 10.1103/PhysRevB.49.12431 PG 15 WC Physics, Condensed Matter SC Physics GA NM433 UT WOS:A1994NM43300002 ER PT J AU RUBINI, S DIMITROPOULOS, C BORSA, F AF RUBINI, S DIMITROPOULOS, C BORSA, F TI MARTENSITIC-TRANSFORMATION IN AG-CD AND CU-ZN ALLOYS STUDIED BY NUCLEAR-MAGNETIC-RESONANCE SO PHYSICAL REVIEW B LA English DT Article ID AL-27 NMR; AL ALLOYS; THERMOELASTICITY; PSEUDOELASTICITY AB Cd-113, Ag-109, and Cu-63 nuclear-magnetic-resonance line-shape and Knight-shift measurements are reported for Ag53.5Cd46.5 and Cu61Zn39 over a temperature interval covering the martensitic phase transformation (MPT) displayed by these alloys. The changes observed in the line shape and width are explained in terms of the changes in atomic coordination and crystal symmetry occurring at the MPT. A small but non-negligible temperature dependence of the Knight shift is observed in the austenitic phase with small discontinuous changes at the transformation for all the nuclei investigated. The difference of resonance frequency of Cd-113 in the two phases has been utilized to obtain the curve of the percentage of martensite in the Ag-Cd alloy as a function of temperature during the thermoelastic transformation. It is shown that our growth curve reveals details which cannot be seen by dynamical methods such as differential scanning calorimetry. C1 UNIV PAVIA,DIPARTIMENTO FIS ALESSANDRO VOLTA,I-27100 PAVIA,ITALY. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. RP RUBINI, S (reprint author), ECOLE POLYTECH FED LAUSANNE,INST PHYS EXPTL,CH-1015 LAUSANNE,SWITZERLAND. RI Rubini, Silvia/C-8369-2012 OI Rubini, Silvia/0000-0001-5215-2223 NR 24 TC 3 Z9 3 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 18 BP 12590 EP 12595 DI 10.1103/PhysRevB.49.12590 PG 6 WC Physics, Condensed Matter SC Physics GA NM433 UT WOS:A1994NM43300021 ER PT J AU BHANOT, G CREUTZ, M GLASSNER, U SCHILLING, K AF BHANOT, G CREUTZ, M GLASSNER, U SCHILLING, K TI SPECIFIC-HEAT EXPONENT FOR THE 3-DIMENSIONAL ISING-MODEL FROM A 24TH-ORDER HIGH-TEMPERATURE SERIES SO PHYSICAL REVIEW B LA English DT Article ID EXPANSIONS AB We compute high temperature expansions of the three-dimensional Ising model using a recursive transfer-matrix algorithm and extend the expansion of the free energy to 24th order. Using inhomogeneous-differential Pade and ratio methods, we extract the critical exponent of the specific heat to be alpha = 0.104(4). C1 INST ADV STUDY,PRINCETON,NJ 08540. BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV WUPPERTAL,DEPT PHYS,D-42097 WUPPERTAL,GERMANY. RP BHANOT, G (reprint author), THINKING MACHINES CORP,245 1ST ST,CAMBRIDGE,MA 02142, USA. NR 17 TC 22 Z9 23 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 18 BP 12909 EP 12914 DI 10.1103/PhysRevB.49.12909 PG 6 WC Physics, Condensed Matter SC Physics GA NM433 UT WOS:A1994NM43300059 ER PT J AU HOWELL, RH STERNE, PA FLUSS, MJ KAISER, JH KITAZAWA, K KOJIMA, H AF HOWELL, RH STERNE, PA FLUSS, MJ KAISER, JH KITAZAWA, K KOJIMA, H TI EVOLUTION OF THE ELECTRONIC-STRUCTURE OF LA2-XSRXCUO4 WITH DOPING DETERMINED BY POSITRON-ANNIHILATION SPECTROSCOPY SO PHYSICAL REVIEW B LA English DT Article ID FERMI-SURFACE; SINGLE-CRYSTAL; YBA2CU3O7-DELTA; BANDS; (LA AB We have measured and calculated the electron-positron momentum distribution Of La2-xSrxCuO4 samples for Sr concentrations of 0, 0.1, 0.13, and 0.2. Measured distributions were obtained at room temperature with high statistical precision, greater than 4X10(8) events, in the Lawrence Livermore National Laboratory positron-annihilation angular correlation spectrometer on single-crystal samples fabricated using the traveling solvent floating zone technique. Corresponding theoretical momentum-density calculations were performed using the linear muffin-tin-orbital method. The momentum distribution of all samples contained features derived from the overlap of the positron distribution with the valence electrons. In addition, discontinuities typical of a Fermi surface are seen in the.doped samples. The form and position of these features are in general agreement with the Fermi surface and overall momentum distributions as predicted by band theory. However, the evolution of the Fermi surface with doping differed significantly from expectations based on single electron band theories. C1 UNIV CALIF DAVIS,DAVIS,CA 95616. UNIV TEXAS,DEPT PHYS,ARLINGTON,TX 76019. UNIV TOKYO,DEPT IND CHEM,TOKYO 113,JAPAN. YAMANASHI UNIV,DEPT PHYS,KOFU,YAMANASHI 400,JAPAN. RP HOWELL, RH (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 20 TC 18 Z9 18 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 18 BP 13127 EP 13136 DI 10.1103/PhysRevB.49.13127 PG 10 WC Physics, Condensed Matter SC Physics GA NM433 UT WOS:A1994NM43300086 ER PT J AU THOMPSON, JR SUN, YR CHRISTEN, DK CIVALE, L MARWICK, AD HOLTZBERG, F AF THOMPSON, JR SUN, YR CHRISTEN, DK CIVALE, L MARWICK, AD HOLTZBERG, F TI OBSERVED REGIMES OF COLLECTIVE FLUX-CREEP IN PROTON-IRRADIATED, SINGLE-CRYSTAL Y-BA-CU-O - DEPENDENCE ON CURRENT-DENSITY SO PHYSICAL REVIEW B LA English DT Note ID HIGH-TC SUPERCONDUCTORS; HIGH-TEMPERATURE SUPERCONDUCTORS; II SUPERCONDUCTORS; MAGNETIC-FIELD; YBA2CU3O7-DELTA; PHASE; IRREVERSIBILITY; LINE AB Flux-creep studies have quantified the time decay of supercurrents in a proton-irradiated YBa2Cu3O7 crystal. We determine the dependence of the characteristic exponent mu (which governs current decay) on current density and magnetic field. The results are compared with collective-creep theory for the case of random pointlike disorder. Observed are predicted regimes of creep with small and large bundles of vortices, indications of single vortex motion, and other consistencies. C1 UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. IBM CORP,THOMAS J WATSON RES CTR,YORKTOWN HTS,NY 10598. RP THOMPSON, JR (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 25 TC 33 Z9 35 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 18 BP 13287 EP 13290 DI 10.1103/PhysRevB.49.13287 PG 4 WC Physics, Condensed Matter SC Physics GA NM433 UT WOS:A1994NM43300119 ER PT J AU BLUMBERG, G LIU, R KLEIN, MV LEE, WC GINSBERG, DM GU, C VEAL, BW DABROWSKI, B AF BLUMBERG, G LIU, R KLEIN, MV LEE, WC GINSBERG, DM GU, C VEAL, BW DABROWSKI, B TI 2-MAGNON RAMAN-SCATTERING IN CUPRATE SUPERCONDUCTORS - EVOLUTION OF MAGNETIC FLUCTUATIONS WITH DOPING SO PHYSICAL REVIEW B LA English DT Note ID OXYGEN-DEFICIENT YBA2CU3O7-DELTA; MOTT-HUBBARD SYSTEMS; SPIN FLUCTUATIONS; NEUTRON-SCATTERING; LIGHT-SCATTERING; SINGLE-CRYSTALS; YBA2CU3O6+X; EXCITATIONS; DYNAMICS; LA2CUO4 AB We report observation and resonance Raman studies of spin-pair excitations in YBa2Cu3O6+x (0.37 < x < 0.7) and YBa2Cu4O8 superconductors. These excitations at energy approximately 3J (2700 +/-150 cm-1), similar to two-magnon excitations in insulators, are evidence that antiferromagnetic fluctuations with spatial extent of at least three lattice constants are not overdamped in the underdoped superconductors. With optimal hole doping, where T(c) > 80 K, the two-magnon peak can no longer be seen above the flat Raman continuum. Photoluminescence and the origin of the broad-spectrum Raman continuum are also discussed. C1 UNIV ILLINOIS,MAT RES LAB,URBANA,IL 61801. UNIV ILLINOIS,DEPT PHYS,URBANA,IL 61801. TALLINN CHEM PHYS & BIOPHYS INST,TALLINN EE0001,ESTONIA. ARGONNE NATL LAB,SCI & TECHNOL CTR SUPERCOND,ARGONNE,IL 60439. ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439. NO ILLINOIS UNIV,DEPT PHYS,DE KALB,IL 60115. RP BLUMBERG, G (reprint author), UNIV ILLINOIS,SCI & TECHNOL CTR SUPERCOND,URBANA,IL 61801, USA. NR 39 TC 41 Z9 41 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0163-1829 J9 PHYS REV B JI Phys. Rev. B PD MAY 1 PY 1994 VL 49 IS 18 BP 13295 EP 13298 DI 10.1103/PhysRevB.49.13295 PG 4 WC Physics, Condensed Matter SC Physics GA NM433 UT WOS:A1994NM43300121 ER PT J AU FLETCHER, KA AYER, Z BLACK, TC DAS, RK KARWOWSKI, HJ LUDWIG, EJ HALE, GM AF FLETCHER, KA AYER, Z BLACK, TC DAS, RK KARWOWSKI, HJ LUDWIG, EJ HALE, GM TI TENSOR ANALYZING POWERS FOR H-2 (D,P)H-3 AND H-2(D,N)HE-3 AT DEUTERON ENERGIES OF 25, 40, 60, AND 80 KEV SO PHYSICAL REVIEW C LA English DT Article ID CROSS-SECTIONS; FUSION; H-2(D,P)H-3; NUCLEI AB Angular distributions of the tensor analyzing powers A(zz) and A(xx) - A(yy) for the reactions H-2(d, p)H-3 and H-2(d, n)He-3 are presented at deuteron energies of 25, 40, 60, and 80 keV. The analyzing powers for the two reaction channels are quite similar at these energies. The data have been included in an R-matrix analysis of the four nucleon system. According to this analysis, transitions from entrance-channel quintet-S states are important in these reactions, so that the use of polarized, fuels would not result in a neutron-lean fusion reaction. C1 UNIV N CAROLINA,DEPT PHYS & ASTRON,CHAPEL HILL,NC 27599. DUKE UNIV,TRIANGLE UNIV NUCL LAB,DURHAM,NC 27708. LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. NR 33 TC 14 Z9 14 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2305 EP 2310 DI 10.1103/PhysRevC.49.2305 PG 6 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200009 ER PT J AU FORNAL, B MAYER, RH BEARDEN, IG BENET, P BRODA, R DALY, PJ GRABOWSKI, ZW AHMAD, I CARPENTER, MP FERNANDEZ, PB JANSSENS, RVF KHOO, TL LAURITSEN, T MOORE, EF DRIGERT, M AF FORNAL, B MAYER, RH BEARDEN, IG BENET, P BRODA, R DALY, PJ GRABOWSKI, ZW AHMAD, I CARPENTER, MP FERNANDEZ, PB JANSSENS, RVF KHOO, TL LAURITSEN, T MOORE, EF DRIGERT, M TI GAMMA-RAY STUDIES OF NEUTRON-RICH SDF SHELL NUCLEI PRODUCED IN HEAVY-ION COLLISIONS SO PHYSICAL REVIEW C LA English DT Article ID ENERGY-LEVELS; S-38 AB Reanalysis of gammagamma coincidence data acquired in studies of superdeformed bands in Hg and Tl nuclei has yielded spectroscopic information about light neutron-rich products of binary reactions of S-34, S-36, and Cl-37 beams on Gd-160 targets. Gates set on known gamma rays in A approximately 160 products selected individual reaction channels and identified coincident gamma rays in A approximately 36 partner products. Transfers of protons from projectile to target and of neutrons from target to projectile were generally favored, leading to excited neutron-rich light nuclei, including some difficult to reach by other means. Notable results include the observation of gamma ray cascades up to the highest known yrast states in four N=20 isotones. In two N=19 nuclei, Si-33 and P-34, and the two N=22 nuclei, 38S and Cl-39, previously unknown yrast states were identified. C1 PURDUE UNIV,DEPT PHYS,W LAFAYETTE,IN 47907. ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. IDAHO NATL ENGN LAB,IDAHO FALLS,ID 83415. INST NUCL PHYS,PL-31342 KRAKOW,POLAND. RP FORNAL, B (reprint author), PURDUE UNIV,DEPT CHEM,W LAFAYETTE,IN 47907, USA. RI Bearden, Ian/M-4504-2014; Carpenter, Michael/E-4287-2015 OI Bearden, Ian/0000-0003-2784-3094; Carpenter, Michael/0000-0002-3237-5734 NR 17 TC 50 Z9 50 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2413 EP 2418 DI 10.1103/PhysRevC.49.2413 PG 6 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200021 ER PT J AU HAMAMOTO, I NAZAREWICZ, W AF HAMAMOTO, I NAZAREWICZ, W TI K-PI=1+ PAIRING INTERACTION AND MOMENTS OF INERTIA OF SUPERDEFORMED ROTATIONAL BANDS IN ATOMIC-NUCLEI SO PHYSICAL REVIEW C LA English DT Article ID HARTREE-FOCK; FREQUENCIES; REGION; STATES; HG-192; SPIN AB The effect of the pairing interaction coming from the rotationally induced K(pi)=1+ pair-density on the nuclear moments of inertia is studied. It is pointed out that, contrary to the situation at normal deformations, the inclusion of the K(pi)=1+ pairing may appreciably modify the frequency dependence of the moments of inertia at superdeformed shapes. C1 UNIV TENNESSEE,DEPT PHYS,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. LUND INST TECHNOL,DEPT MATH PHYS,S-22100 LUND,SWEDEN. UNIV WARSAW,INST THEORET PHYS,PL-00681 WARSAW,POLAND. WARSAW INST TECHNOL,INST PHYS,WARSAW,POLAND. RP HAMAMOTO, I (reprint author), OAK RIDGE NATL LAB,JOINT INST HEAVY ION RES,POB 2008,OAK RIDGE,TN 37831, USA. NR 30 TC 20 Z9 20 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2489 EP 2492 DI 10.1103/PhysRevC.49.2489 PG 4 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200030 ER PT J AU PAN, XW FENG, DH CHEN, JQ GUIDRY, MW AF PAN, XW FENG, DH CHEN, JQ GUIDRY, MW TI TAU COMPRESSION IN THE SO(5) SCHEME SO PHYSICAL REVIEW C LA English DT Article ID INTERACTING BOSON MODEL; DYNAMICAL SYMMETRY MODEL; NUCLEI; STATES; REGION; LIMIT AB It is shown that tau-dependent compression of energy levels occurs in most SO(6)-like nuclei, where tau is the SO(5) quantum number. We suggest that this compression represents a generalization of the Coriolis antipairing effect to symmetries other than SU(3), and that it is effectively described by an SO(6)-plus-pairing model. C1 NANJING UNIV,DEPT PHYS,NANJING 210008,PEOPLES R CHINA. UNIV PENN,DEPT PHYS,PHILADELPHIA,PA 19104. UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. RP PAN, XW (reprint author), DREXEL UNIV,DEPT PHYS,PHILADELPHIA,PA 19104, USA. NR 28 TC 5 Z9 6 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2493 EP 2498 DI 10.1103/PhysRevC.49.2493 PG 6 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200031 ER PT J AU WEISS, R ACLANDER, J ALSTER, J BARAKAT, M BART, S CHRIEN, RE KRAUSS, RA JOHNSTON, K MARDOR I MARDOR, Y TALBECK, SM PIASETZKY, E PILE, PH SAWAFTA, R SEYFARTH, H STEARNS, RL SUTTER, RJ YAVIN, AI AF WEISS, R ACLANDER, J ALSTER, J BARAKAT, M BART, S CHRIEN, RE KRAUSS, RA JOHNSTON, K MARDOR, I MARDOR, Y TALBECK, SM PIASETZKY, E PILE, PH SAWAFTA, R SEYFARTH, H STEARNS, RL SUTTER, RJ YAVIN, AI TI MEASUREMENT OF LOW-ENERGY K+ TOTAL CROSS-SECTIONS ON N = Z NUCLEI SO PHYSICAL REVIEW C LA English DT Article ID SCATTERING; EXCHANGE; MESONS AB The total cross sections for K+ on deuterium, Li-6, C-12, Si-28, and Ca-40 have been measured at four-momenta in the range 480-714 MeV/c. The experimental technique was of the standard transmission type. Because of its long mean free path in nuclear matter at low energies the K+ can be expected to probe the entire volume of the nucleus. Indeed we found that, to better than 10%, sigma(K+A) = Asigma(K+N) up to A = 40. This feature was used to study more delicate effects of the nuclear medium. Special emphasis was placed on measuring the total cross section ratios of K+A to K+D with a precision of < 2%. This ratio is a good measure of nuclear medium effects because many experimental as well as theoretical systematic uncertainties cancel in the ratio. We discuss the medium dependence as a function of A. The data do not agree with calculations which include only conventional medium effects. This points towards the need of unconventional nuclear medium effects such as partial quark deconfinement, mass rescaling of nuclear pionic fields, or pion excess in nuclei. Thus far only calculations based on unconventional medium effects for C-12 exist. Calculations for the other nuclei are needed before quantitative conclusions can be drawn. C1 BROOKHAVEN NATL LAB, UPTON, NY 11973 USA. UNIV HOUSTON, HOUSTON, TX 77204 USA. TEXAS A&M UNIV, COLLEGE STN, TX 77843 USA. FORSCHUNGSZENTRUM JULICH, W-5170 JULICH 1, GERMANY. VASSAR COLL, POUGHKEEPSIE, NY 12601 USA. RP WEISS, R (reprint author), TEL AVIV UNIV, RAYMOND & BEVERLY SACKLER FAC EXACT SCI, SCH PHYS, IL-69978 TEL AVIV, ISRAEL. NR 20 TC 56 Z9 57 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2569 EP 2577 DI 10.1103/PhysRevC.49.2569 PG 9 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200038 ER PT J AU BARTEL, J JOHNSON, MB SINGHAM, M STOCKER, W AF BARTEL, J JOHNSON, MB SINGHAM, M STOCKER, W TI MICROSCOPIC COUPLED-CHANNEL DESCRIPTION OF PION INELASTIC-SCATTERING FROM ROTATIONAL NUCLEI SO PHYSICAL REVIEW C LA English DT Article ID CHARGE-EXCHANGE SCATTERING; CALCIUM ISOTOPES; RESONANCE REGION; EFFECTIVE FORCES; SINGLE; SM-152 AB We establish the applicability of a microscopic coupled-channel theory to pion inelastic scattering from rotational nuclei for the purpose of studying details of neutron and proton densities. The theory is completely specified as a result of our taking the second-order pion-nucleus optical potential from previous phenomenological studies of elastic and charge-exchange data on spherical nuclei and of our using nuclear wave functions obtained from a Hartree-Fock + BCS calculation with the Skyrme SKM* interaction. Making multipole expansions leads to a set of coupled equations, which is solved for the scattering cross sections in a standard manner. Numerical studies are presented for the specific nucleus Sm-152. The theory is shown to be stable with respect to truncation of the expansions: we find rapid convergence of the cross sections for elastic scattering and inelastic scattering to the first 2+ and 4+ states as transition densities of successively higher multipolarity are added, and as the number of coupled rotational nuclear levels is increased. Medium modifications are included and have a small but significant effect on the cross section: for scattering to the 2+ state, their effect is about 10% for both pi- and pi+. We also quantify the extent of sensitivity of pion scattering cross sections to variations in the size and shape of the neutron and proton distribution. using parametrized Woods-Saxon forms for the density. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. NR 22 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2592 EP 2601 DI 10.1103/PhysRevC.49.2592 PG 10 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200041 ER PT J AU MUSTAFA, MG BLANN, M PEILERT, G BOTVINA, A AF MUSTAFA, MG BLANN, M PEILERT, G BOTVINA, A TI COMPARISON OF FAST CASCADE PLUS STATISTICAL-MODELS FOR HEAVY-ION-INDUCED MULTIFRAGMENTATION REACTIONS SO PHYSICAL REVIEW C LA English DT Article ID MOMENTUM-TRANSFER; FRAGMENT FLOW; BREAK-UP; NUCLEI; MEV/NUCLEON; COLLISIONS; DYNAMICS; DECAY AB We consider the reaction Ar-36 + Au-197 at incident Ar-36 energies of 35, 50, 80, and 110A MeV, comparing calculations of precompound decay using the Boltzmann master equation (BME) and quantum molecular dynamics (QMD) models. We then estimate quasiequilibrated nuclei and excitations using the BME model, and use these values as input into statistical multifragmentation models. For the latter we compare sequential binary decay as an extension of the Weisskopf-Ewing evaporation model, and a simultaneous multifragmentation for an expanded low density gas. The exclusive multiplicities predicted by these models are compared with experimental results. C1 RUSSIAN ACAD SCI,INST NUCL RES,MOSCOW 117312,RUSSIA. RP MUSTAFA, MG (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 25 TC 5 Z9 5 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2602 EP 2607 DI 10.1103/PhysRevC.49.2602 PG 6 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200042 ER PT J AU GACSI, Z RAMAN, S AF GACSI, Z RAMAN, S TI DECAYS OF SB-116 ISOMERS TO LEVELS IN SN-116 SO PHYSICAL REVIEW C LA English DT Note AB The excited states of Sn-116 were studied by means of the decays of the 15.8-min, 3+Sb-116 ground state, and the 60.3-min, 8-Sb-116 isomer. Over 50 gamma rays were observed; these were incorporated into a level scheme consisting of 32 excited states. Except for one new level proposed at 3.986 MeV, the current study fully supports an exhaustive study of levels in Sn-116 reported earlier. The previous study was an attempt to develop a nearly ''complete'' level scheme of Sn-116 up to an excitation energy of 4.3 MeV. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP GACSI, Z (reprint author), HUNGARIAN ACAD SCI,INST NUCL RES,H-4001 DEBRECEN,HUNGARY. NR 12 TC 5 Z9 5 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2792 EP 2795 DI 10.1103/PhysRevC.49.2792 PG 4 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200063 ER PT J AU HENRY, EA KUHNERT, A BECKER, JA BRINKMAN, MJ WANG, TF CIZEWSKI, JA KORTEN, W AZAIEZ, F DELEPLANQUE, MA DIAMOND, RM DRAPER, JE KELLY, WH MACCHIAVELLI, AO STEPHENS, FS AF HENRY, EA KUHNERT, A BECKER, JA BRINKMAN, MJ WANG, TF CIZEWSKI, JA KORTEN, W AZAIEZ, F DELEPLANQUE, MA DIAMOND, RM DRAPER, JE KELLY, WH MACCHIAVELLI, AO STEPHENS, FS TI LACK OF EVIDENCE FOR A SUPERDEFORMED BAND IN PB-192 - COMMENT SO PHYSICAL REVIEW C LA English DT Letter AB This Comment examines the claim of a lack of evidence for a superdeformed band in Pb-192. We reaffirm the existence in our data of the superdeformed band in Pb-192. C1 CALTECH,PASADENA,CA 91125. RUTGERS STATE UNIV,NEW BRUNSWICK,NJ 08903. UNIV BONN,D-53115 BONN,GERMANY. INST PHYS NUCL LYON,F-91406 ORSAY,FRANCE. LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. UNIV CALIF DAVIS,DAVIS,CA 95616. IOWA STATE UNIV SCI & TECHNOL,AMES,IA 50011. RP HENRY, EA (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. RI KORTEN, Wolfram/H-3043-2013 NR 4 TC 6 Z9 6 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2849 EP 2850 DI 10.1103/PhysRevC.49.2849 PG 2 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200079 ER PT J AU PLOMPEN, AJM HARAKEH, MN HESSELINK, WHA VANTHOF, G KALANTARNAYESTANAKI, N VANSCHAGEN, JPS JANSSENS, RVF AHMAD, I BEARDEN, IG CARPENTER, MP KHOO, TL LAURITSEN, T LIANG, Y GARG, U REVIOL, W YE, D AF PLOMPEN, AJM HARAKEH, MN HESSELINK, WHA VANTHOF, G KALANTARNAYESTANAKI, N VANSCHAGEN, JPS JANSSENS, RVF AHMAD, I BEARDEN, IG CARPENTER, MP KHOO, TL LAURITSEN, T LIANG, Y GARG, U REVIOL, W YE, D TI LACK OF EVIDENCE FOR A SUPERDEFORMED BAND IN (192)PB - REPLY SO PHYSICAL REVIEW C LA English DT Letter ID PB-192 AB In reply to the preceding Comment, we wish to stress that lack of consistency between experiments of similar quality justifies our claim that further searches for a superdeformed band in Pb-192 with more powerful instruments are called for. We believe that the main results presented in the Comment support this conclusion. C1 FREE UNIV AMSTERDAM,FAC NAT KUNDE STERRENKUNDE,1081 HV AMSTERDAM,NETHERLANDS. ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. UNIV NOTRE DAME,DEPT PHYS,NOTRE DAME,IN 46556. RI Bearden, Ian/M-4504-2014; Carpenter, Michael/E-4287-2015; Kalantar-Nayestanaki, Nasser/A-3582-2016 OI Bearden, Ian/0000-0003-2784-3094; Carpenter, Michael/0000-0002-3237-5734; Kalantar-Nayestanaki, Nasser/0000-0002-1033-7200 NR 3 TC 3 Z9 3 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP 2851 EP 2851 DI 10.1103/PhysRevC.49.2851 PG 1 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200080 ER PT J AU PEASLEE, GF TSANG, MB SCHWARZ, C HUANG, MJ HUANG, WS HSI, WC WILLIAMS, C BAUER, W BOWMAN, DR CHARTIER, M DINIUS, J GELBKE, CK GLASMACHER, T HANDZY, DO LISA, MA LYNCH, WG MADER, CM PHAIR, L LEMAIRE, MC SOUZA, SR VANBUREN, G CHARITY, RJ SOBOTKA, LG KUNDE, GJ LYNEN, U POCHODZALLA, J SANN, H TRAUTMANN, W FOX, D DESOUZA, RT PEILERT, G FRIEDMAN, WA CARLIN, N AF PEASLEE, GF TSANG, MB SCHWARZ, C HUANG, MJ HUANG, WS HSI, WC WILLIAMS, C BAUER, W BOWMAN, DR CHARTIER, M DINIUS, J GELBKE, CK GLASMACHER, T HANDZY, DO LISA, MA LYNCH, WG MADER, CM PHAIR, L LEMAIRE, MC SOUZA, SR VANBUREN, G CHARITY, RJ SOBOTKA, LG KUNDE, GJ LYNEN, U POCHODZALLA, J SANN, H TRAUTMANN, W FOX, D DESOUZA, RT PEILERT, G FRIEDMAN, WA CARLIN, N TI ENERGY-DEPENDENCE OF MULTIFRAGMENTATION IN KR-84 PLUS AU-197 COLLISIONS SO PHYSICAL REVIEW C LA English DT Note ID HEAVY-ION COLLISIONS; MASS FRAGMENT EMISSION; E/A = 50; NUCLEAR FRAGMENTATION; IMPACT-PARAMETER; AR-36+AU-197; PROJECTILES; ENTROPY; MATTER; DECAY AB The relationship between observed intermediate mass fragment and total charged particle multiplicities has been measured for Kr-84 + Au-197 collisions at energies between E/A = 35 and 400 MeV. Fragment multiplicities are greatest for central or near-central collisions. For these collisions, fragment production increases up to E/A almost-equal-to 100 MeV, and then decreases at higher energies. C1 MICHIGAN STATE UNIV, NATL SUPERCOND CYCLOTRON LAB, E LANSING, MI 48824 USA. MICHIGAN STATE UNIV, DEPT PHYS & ASTRON, E LANSING, MI 48824 USA. CENS, LAB NATL SATURNE, F-91191 GIF SUR YVETTE, FRANCE. WASHINGTON UNIV, DEPT CHEM, ST LOUIS, MO 63130 USA. GESELL SCHWERIONENFORSCH MBH, W-6100 DARMSTADT 11, GERMANY. INDIANA UNIV, DEPT CHEM, BLOOMINGTON, IN 47405 USA. INDIANA UNIV, IUCF, BLOOMINGTON, IN 47405 USA. UNIV WISCONSIN, DEPT PHYS, MADISON, WI 53706 USA. LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. UNIV SAO PAULO, INST FIS, BR-01498 SAO PAULO, BRAZIL. RI Glasmacher, Thomas/C-4462-2008; Carlin Filho, Nelson/C-2187-2012; Souza, Sergio/B-8903-2013; Lynch, William/I-1447-2013; Glasmacher, Thomas/H-9673-2014; deSouza, Romualdo/P-5862-2015 OI Lynch, William/0000-0003-4503-176X; Glasmacher, Thomas/0000-0001-9436-2448; deSouza, Romualdo/0000-0001-5835-677X NR 36 TC 71 Z9 74 U1 1 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9985 EI 2469-9993 J9 PHYS REV C JI Phys. Rev. C PD MAY PY 1994 VL 49 IS 5 BP R2271 EP R2275 DI 10.1103/PhysRevC.49.R2271 PG 5 WC Physics, Nuclear SC Physics GA NN542 UT WOS:A1994NN54200001 ER PT J AU GOMEZ, J ARNOLD, RG BOSTED, PE CHANG, CC KATRAMATOU, AT PETRATOS, GG RAHBAR, AA ROCK, SE SILL, AF SZALATA, ZM BODEK, A GIOKARIS, N SHERDEN, DJ MECKING, BA LOMBARDNELSEN, RM AF GOMEZ, J ARNOLD, RG BOSTED, PE CHANG, CC KATRAMATOU, AT PETRATOS, GG RAHBAR, AA ROCK, SE SILL, AF SZALATA, ZM BODEK, A GIOKARIS, N SHERDEN, DJ MECKING, BA LOMBARDNELSEN, RM TI MEASUREMENT OF THE A-DEPENDENCE OF DEEP-INELASTIC ELECTRON-SCATTERING SO PHYSICAL REVIEW D LA English DT Article ID NUCLEAR-STRUCTURE FUNCTIONS; HIGH MOMENTUM-TRANSFER; R=SIGMA-L/SIGMA-T; LEPTON SCATTERING; QUARK DISTRIBUTIONS; CROSS-SECTIONS; FERMI-MOTION; MUON SCATTERING; GLOBAL ANALYSIS; IRON TARGETS AB Cross sections for deep-inelastic electron scattering from liquid deuterium, gaseous He-4, and solid Be, C, Al, Ca, Fe, Ag, and Au targets were measured at the Stanford Linear Accelerator Center using electrons with energies ranging from 8 to 24.5 GeV. These data cover a range in the Bjorken variable x from 0.089 to 0.8, and in momentum transfer Q2 from 2 to 15 (GeV/c)2. The ratios of cross sections per nucleon sigma(A)/sigma(d))is for isoscalar nuclei have been extracted from the data. These ratios are greater than unity in the range 0.1 < x < 0.3, while for 0.3 < x < 0.8 they are less than unity and decrease logarithmically with atomic weight A, or linearly with average nuclear density. No Q2 dependence in the ratios was observed over the kinematic range of the data. These results are compared to various theoretical predictions. C1 AMERICAN UNIV,DEPT PHYS,WASHINGTON,DC 20016. STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309. UNIV BONN,W-5300 BONN,GERMANY. CTR ETUD SACLAY,DAPNIA SPHN,F-91191 GIF SUR YVETTE,FRANCE. UNIV MARYLAND,DEPT PHYS,COLLEGE PK,MD 20742. NR 101 TC 228 Z9 228 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4348 EP 4372 DI 10.1103/PhysRevD.49.4348 PG 25 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500007 ER PT J AU URIBE, J HARTOUNI, EP JENSEN, DA KREISLER, MN CHURCH, MD GOTTSCHALK, EE KNAPP, BC SIPPACH, W STERN, BJ WIENCKE, LR CHRISTIAN, DC GUTIERREZ, G HOLMES, SD WEHMANN, A AVILEZ, C FORBUSH, M HUSON, FR WHITE, JT AF URIBE, J HARTOUNI, EP JENSEN, DA KREISLER, MN CHURCH, MD GOTTSCHALK, EE KNAPP, BC SIPPACH, W STERN, BJ WIENCKE, LR CHRISTIAN, DC GUTIERREZ, G HOLMES, SD WEHMANN, A AVILEZ, C FORBUSH, M HUSON, FR WHITE, JT TI PION-PION CORRELATIONS AT LOW RELATIVE MOMENTUM PRODUCED IN P-P COLLISIONS AT 27.5 GEV/C SO PHYSICAL REVIEW D LA English DT Article ID BOSE-EINSTEIN CORRELATIONS; INTERFEROMETRY; PHYSICS; PLASMA AB We have measured the momentum correlation of pion pairs produced in the collisions of 27.5 GeV/c protons in liquid hydrogen. By considering events for which all final state particles have been measured, we have succeeded in reducing backgrounds due to particle misidentification below 5% for pi+ and 1% for pi-. Our use of a precision magnetic spectrometer has provided an accurate determination of particle momenta and excellent acceptance for particle pairs with small relative momentum essential for correlations studies. A large data sample of fully reconstructed events (1 X 10(6)) allows us to analyze the correlations for pi+pi+ and pi-pi- pairs separately, and also as a function of the final state multiplicity. We find that the pion pair correlations scale, 0.98 fm describes the data well. We do not find any indication of multiplicity dependence of the correlation scale for multiplicities from 6 to 14 final state particles. C1 UNIV MASSACHUSETTS,DEPT PHYS & ASTRON,AMHERST,MA 01003. COLUMBIA UNIV,NEVIS LABS,IRVINGTON,NY 10533. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. UNIV GUANAJUATO,INST FIS,LEON,GUANAJUATO,MEXICO. TEXAS A&M UNIV,DEPT PHYS,COLLEGE STN,TX 77843. OI Hartouni, Edward/0000-0001-9869-4351 NR 38 TC 26 Z9 26 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4373 EP 4393 DI 10.1103/PhysRevD.49.4373 PG 21 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500008 ER PT J AU MAHLON, G AF MAHLON, G TI MULTIGLUON HELICITY AMPLITUDES INVOLVING A QUARK LOOP SO PHYSICAL REVIEW D LA English DT Article ID GAUGE-THEORIES; MULTIPLE BREMSSTRAHLUNG; HIGH-ENERGIES; SUPERSYMMETRY AB We apply the solution to the recursion relation for the double-off-shell quark current to the problem of computing one-loop amplitudes with an arbitrary number of gluons. We are able to compute amplitudes for photon-gluon scattering, electron-positron annihilation to gluons, and gluon-gluon scattering via a quark loop in the case of like-helicity gluons. In addition, we present the result for the one-loop gluon-gluon scattering amplitude when one of the gluons has opposite helicity from the others. RP MAHLON, G (reprint author), FERMILAB NATL ACCELERATOR LAB,POB 500,BATAVIA,IL 60510, USA. NR 34 TC 75 Z9 75 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4438 EP 4453 DI 10.1103/PhysRevD.49.4438 PG 16 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500014 ER PT J AU HILL, CT PARKE, SJ AF HILL, CT PARKE, SJ TI TOP-QUARK PRODUCTION - SENSITIVITY TO NEW PHYSICS SO PHYSICAL REVIEW D LA English DT Article ID STANDARD MODEL; TECHNICOLOR; CONDENSATION; HIERARCHIES; SIGNATURES; COLLIDERS; BREAKING AB The production cross section and distributions of the top quark are sensitive to new physics; e.g., the ttBAR system can be a probe of new resonances or gauge bosons that are strongly coupled to the top quark, in analogy with Drell-Yan production. The existence of such new physics is expected in dynamical electroweak symmetry-breaking schemes, and associated with the large mass of the top quark. The total top quark production cross section can be more than doubled, and distributions significantly distorted with a chosen scale of new physics of approximately 1 TEV in the vector color singlet or octet s channel. New resonance physics is most readily discernible in the high-P(T) distributions of the single top quark and of the W boson, and the mass distribution of the ttBAR pair. RP HILL, CT (reprint author), FERMILAB NATL ACCELERATOR LAB,POB 500,BATAVIA,IL 60510, USA. NR 23 TC 231 Z9 233 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4454 EP 4462 DI 10.1103/PhysRevD.49.4454 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500015 ER PT J AU LEVIN, E AF LEVIN, E TI HARD POMERON APPROACH TO SOFT PROCESSES AT HIGH-ENERGY SO PHYSICAL REVIEW D LA English DT Article ID DUAL-PARTON MODEL; ELASTIC-SCATTERING; CROSS-SECTIONS; QCD; COLLISIONS; DISSOCIATION; MINIJETS; ORDER AB An attempt is made to give a consistent description of high energy hadron interactions starting with the physical assumption that only ''hard'' processes contribute to the Pomeron structure. Using the general properties of a ''hard'' Pomeron in perturbative QCD an equation for shadowing corrections is suggested and solved. It allows one to extend the new approach to high energy hadron collisons. In doing so we generalize the so-called eikonal approximation widely used to describe the shadowing corrections for both hadron and nucleus scattering at high energy. New formulas are also suggested for the large rapidity gap survival probability which crucially differ from the eikonal ones. C1 ST PETERSBURG NUCL PHYS INST,GATCHINA 188350,RUSSIA. RP LEVIN, E (reprint author), FERMILAB NATL ACCELERATOR LAB,POB 500,BATAVIA,IL 60510, USA. NR 54 TC 11 Z9 11 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4469 EP 4480 DI 10.1103/PhysRevD.49.4469 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500017 ER PT J AU BERNREUTHER, W BRANDENBURG, A AF BERNREUTHER, W BRANDENBURG, A TI TRACING CP VIOLATION IN THE PRODUCTION OF TOP-QUARK PAIRS BY MULTIPLE TEV PROTON-PROTON COLLISIONS SO PHYSICAL REVIEW D LA English DT Article ID ELECTRIC-DIPOLE MOMENT; BARYON ASYMMETRY; GAUGE THEORY; FORM-FACTORS; NONCONSERVATION; MODEL; DOUBLETS; SUPERCOLLIDERS; LEPTON; DECAYS AB We investigate the possibilities of searching for nonstandard CP violation in pp --> ttXBAR at multiple TeV collision energies. A general kinematic analysis of the underlying partonic production processes gg --> ttBAR and qqBAR --> ttBAR in terms of their density matrices is given. We evaluate the CP-violating parts of these matrices in two-Higgs-doublet extensions of the standard model (SM) and give results for CP asymmetries at the parton level. We show that these asymmetries can be traced by measuring suitable observables constructed from energies and momenta of the decay products of t and tBAR. We find CP-violating effects to be of the order of 10(-3) and show that possible contaminations induced by SM interactions are safely below the expected signals. C1 STANFORD LINEAR ACCELERATOR CTR, STANFORD, CA 94309 USA. RP RHEINISCH WESTFAL TH AACHEN, INST THEORET PHYS, ZENTRUM PHYS, D-52056 AACHEN, GERMANY. NR 59 TC 85 Z9 85 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4481 EP 4492 DI 10.1103/PhysRevD.49.4481 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500018 ER PT J AU ESKOLA, KJ WANG, XN AF ESKOLA, KJ WANG, XN TI MINIJET-ASSOCIATED DILEPTON PRODUCTION IN ULTRARELATIVISTIC HEAVY-ION COLLISIONS SO PHYSICAL REVIEW D LA English DT Article ID DRELL-YAN PROCESS; NUCLEUS-NUCLEUS COLLISIONS; QUARK-QUARK CONTRIBUTION; LEPTON-PAIR PRODUCTION; LUND MONTE-CARLO; HADRON-COLLISIONS; QCD JETS; PARTICLE-PRODUCTION; ORDER ALPHA-S(3); GLUON PRODUCTION AB Dilepton production associated with minijets is calculated in ultrarelativistic heavy ion collisions using the first order approximation of the dilepton fragmentation functions of quarks and gluons. The full QCD evolution of the fragmentation functions is also studied. We find that the dilepton pairs from the fragmentation of minijets are comparable to direct Drell-Yan production at square-root s = 200A GeV for small dilepton invariant masses M approximately 1-2 GeV/c2 while they are dominant over a large range of mass at square-root s = 6400A GeV. C1 LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. RP ESKOLA, KJ (reprint author), UNIV HELSINKI,HIGH ENERGY PHYS LAB,POB 9,SF-00014 HELSINKI,FINLAND. OI Wang, Xin-Nian/0000-0002-9734-9967 NR 57 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4532 EP 4541 DI 10.1103/PhysRevD.49.4532 PG 10 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500024 ER PT J AU ESKOLA, KJ WANG, XN AF ESKOLA, KJ WANG, XN TI CALCULATING DILEPTON RATES FROM MONTE-CARLO SIMULATIONS OF PARTON PRODUCTION SO PHYSICAL REVIEW D LA English DT Article ID HEAVY-ION COLLISIONS; DRELL-YAN PROCESS; PARTICLE-PRODUCTION; JET FRAGMENTATION; E+E-PHYSICS; QCD JETS; MODEL AB To calculate dilepton rates in a Monte Carlo simulation of ultrarelativistic heavy ion collisions, one can scale the number of similar QCD processes by a ratio of the corresponding differential probabilities. We derive the formula for such a ratio especially for dilepton bremsstrahlung processes. We also discuss the non-triviality of including higher order corrections to the direct Drell-Yan process. The resultant mass spectra from our Monte Carlo simulation are consistent with the semianalytical calculation using dilepton fragmentation functions. C1 LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. RP ESKOLA, KJ (reprint author), UNIV HELSINKI,HIGH ENERGY PHYS LAB,POB 9,SF-00014 HELSINKI,FINLAND. OI Wang, Xin-Nian/0000-0002-9734-9967 NR 22 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4542 EP 4547 DI 10.1103/PhysRevD.49.4542 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500025 ER PT J AU HAWES, FT ROBERTS, CD WILLIAMS, AG AF HAWES, FT ROBERTS, CD WILLIAMS, AG TI DYNAMICAL CHIRAL-SYMMETRY BREAKING AND CONFINEMENT WITH AN INFRARED-VANISHING GLUON PROPAGATOR SO PHYSICAL REVIEW D LA English DT Article ID SCHWINGER-DYSON EQUATIONS; YANG-MILLS FIELD; QUANTUM CHROMODYNAMICS; QUARK PROPAGATOR; NONPERTURBATIVE SOLUTION; SELF-CONSISTENCY; LANDAU GAUGE; QCD; VERTEX; MODEL AB We study a model Dyson-Schwinger equation for the quark propagator closed using an Ansatz for the gluon propagator of the form D(q) is similar to q2/[(q2)2 + b4] and two Ansatze for the quark-gluon vertex: the minimal Ball-Chiu form and the modified form suggested by Curtis and Pennington. Using the quark condensate as an order parameter, we find that there is a critical value of b = b(c) such that the model does not support dynamical chiral symmetry breaking for b > b(c). We discuss and apply a confinement test which suggests that, for all values of b, the quark propagator in the model is not confining. Together these results suggest that this Ansatz for the gluon propagator is inadequate as a model since it does not yield the expected behavior of QCD. C1 FLORIDA STATE UNIV,SCRI,TALLAHASSEE,FL 32306. ARGONNE NATL LAB,DIV PHYS,ARGONNE,IL 60439. UNIV ADELAIDE,DEPT PHYS & MATH PHYS,ADELAIDE,SA 5001,AUSTRALIA. RP HAWES, FT (reprint author), FLORIDA STATE UNIV,DEPT PHYS,TALLAHASSEE,FL 32306, USA. RI Williams, Anthony/I-6698-2012; OI Roberts, Craig/0000-0002-2937-1361; Williams, Anthony/0000-0002-1472-1592 NR 73 TC 59 Z9 59 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4683 EP 4693 DI 10.1103/PhysRevD.49.4683 PG 11 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500040 ER PT J AU HEISELBERG, H AF HEISELBERG, H TI VISCOSITIES OF QUARK-GLUON PLASMAS SO PHYSICAL REVIEW D LA English DT Article ID FINITE TEMPERATURE; TRANSVERSE INTERACTIONS; QCD; TRANSPORT AB The quark and gluon viscosities are calculated in quark-gluon plasmas to leading orders in the coupling constant by including screening. For weakly interacting QCD and QED plasmas, dynamical screening of transverse interactions and Debye screening of longitudinal interactions controls the infrared divergences. For strongly interacting plasmas other screening mechanisms taken from lattice calculations are employed. By solving the Boltzmann equation for quarks and gluons including screening, the viscosity is calculated to leading orders in the coupling constant. The leading logarithmic order is calculated exactly by a full variational treatment. The next to leading orders are found to be important for the transport properties of quark-gluon plasmas created in relativistic heavy-ion collisions and the early universe, where the coupling constant is large. RP HEISELBERG, H (reprint author), LAWRENCE BERKELEY LAB,DIV NUCL SCI,MS 70A-3307,BERKELEY,CA 94720, USA. OI Heiselberg, Henning/0000-0003-2229-2000 NR 31 TC 61 Z9 62 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4739 EP 4750 DI 10.1103/PhysRevD.49.4739 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500044 ER PT J AU CHENG, HC GILL, MS HALL, LJ AF CHENG, HC GILL, MS HALL, LJ TI SO(10) OPERATOR ANALYSIS FOR NU(MU)NU(TAU) OSCILLATIONS SO PHYSICAL REVIEW D LA English DT Article ID GRAND UNIFIED THEORIES; FERMION MASS MATRICES; SUPERSYMMETRY; UNIFICATION; PREDICTIONS; ANSATZ; SU(5) AB In grand unified theories the flavor mixing angles of leptons are related to those of quarks. In this paper we study SO(10) theories with a precise group-theoretic relation at the GUT scale for mixing between the heaviest two generations: theta(mutau)0 = kappa\V(cb)0\. A comprehensive operator search yields all possible cases where kappa is a group theory Clebsch coefficient. The resulting predictions for nu(mu)nu(tau) oscillations are scaled from the grand to the weak scales. We find that all but one of the models which have such a relationship between theta(mutau)0 and V(cb)0, and are not already excluded, will be probed by the CHORUS and NOMAD experiments. A more precise mixing measurement, for example, by the proposed P803 experiment, could distinguish between the models. C1 LAWRENCE BERKELEY LAB,DIV PHYS,THEORET PHYS GRP,BERKELEY,CA 94720. RP CHENG, HC (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. NR 39 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4826 EP 4834 DI 10.1103/PhysRevD.49.4826 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500056 ER PT J AU LYKKEN, JD WILLENBROCK, S AF LYKKEN, JD WILLENBROCK, S TI PLANCK-SCALE UNIFICATION AND DYNAMICAL SYMMETRY-BREAKING SO PHYSICAL REVIEW D LA English DT Article ID GRAND UNIFIED THEORIES; TECHNICOLOR THEORIES; STANDARD MODEL; STRING UNIFICATION; ELECTROWEAK PARAMETERS; ANOMALY CANCELLATION; CHIRAL HIERARCHIES; GAUGE-THEORIES; HYPERCOLOR; MASS AB We explore the possibility of unification of gauge couplings near the Planck scale in models of extended technicolor. We observe that models of the form G X SU(3)c X SU(2)L X U(1)Y cannot be realized, due to the presence of massless neutral Goldstone bosons (axions) and light charged pseudo Goldstone bosons; thus, unification of the known forces near the Planck scale cannot be achieved. The next simplest possibility, G X SU(4)PS X SU(2)L X U(1)T3R, cannot lead to unification of the Pati-Salam and weak gauge groups near the Planck scale. However, superstring theory provides relations between couplings at the Planck scale without the need for an underlying grand-unified gauge group, which allows unification of the SU(4)PS and SU(2)L couplings. C1 FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. BROOKHAVEN NATL LAB,DEPT PHYS,UPTON,NY 11973. RP LYKKEN, JD (reprint author), UNIV CALIF SANTA BARBARA,INST THEORET PHYS,SANTA BARBARA,CA 93106, USA. NR 82 TC 7 Z9 7 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP 4902 EP 4907 DI 10.1103/PhysRevD.49.4902 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500061 ER PT J AU ALVES, GA AMATO, S ANJOS, JC APPEL, JA ASTORGA, J BRACKER, SB CREMALDI, LM DARLING, CL DIXON, RL ERREDE, D FENKER, HC GAY, C GREEN, DR HALLING, AM JEDICKE, R KARCHIN, PE KWAN, S LUEKING, LH MANTSCH, PM NETO, JRTD METHENY, J MILBURN, RH DEMIRANDA, JM DAMOTTA, H NAPIER, A PASSMORE, D RAFATIAN, A DOSREIS, AC ROSS, WR SANTORO, AFS SHEAFF, M SOUZA, MHG SPALDING, WJ STOUGHTON, C STREETMAN, ME SUMMERS, DJ TAKACH, SF WALLACE, A WU, Z AF ALVES, GA AMATO, S ANJOS, JC APPEL, JA ASTORGA, J BRACKER, SB CREMALDI, LM DARLING, CL DIXON, RL ERREDE, D FENKER, HC GAY, C GREEN, DR HALLING, AM JEDICKE, R KARCHIN, PE KWAN, S LUEKING, LH MANTSCH, PM NETO, JRTD METHENY, J MILBURN, RH DEMIRANDA, JM DAMOTTA, H NAPIER, A PASSMORE, D RAFATIAN, A DOSREIS, AC ROSS, WR SANTORO, AFS SHEAFF, M SOUZA, MHG SPALDING, WJ STOUGHTON, C STREETMAN, ME SUMMERS, DJ TAKACH, SF WALLACE, A WU, Z TI D-ASTERISK+/- PRODUCTION IN 250 GEV PI+/-N INTERACTIONS SO PHYSICAL REVIEW D LA English DT Note ID HADRONIC COLLISIONS; P INTERACTIONS; D-STAR; MESONS AB We report results from Fermilab experiment E769 on the differential cross sections of D*+/- charm vector mesons with respect to Feynman-x (x(F)) and transverse momentum (P(T)), and on the atomic mass dependence of the production. The D* mesons were produced by a 250 GeV pi beam on a target of Be, Al, Cu, and W foils. The dsigma/dx(F) distribution is fit by the form (1 - x(F))n with n = 3.5 +/- 0.3 +/- 0.1, the dsigma/dP(T)2 distribution by exp(-b x P(T)2) with b = 0.70 +/- 0.07 +/- 0.04 GeV-2, and the cross section A dependence by A(alpha) with alpha = 1.00 +/- 0.07 +/- 0.02. These results are compared to the equivalent parameters for the production of pseudoscalar D0 and D+/- charm mesons. C1 FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. UNIV MISSISSIPPI,OXFORD,MS 38677. UNIV TORONTO,TORONTO M5S 1A7,ONTARIO,CANADA. TUFTS UNIV,MEDFORD,MA 02155. UNIV WISCONSIN,MADISON,WI 53706. YALE UNIV,NEW HAVEN,CT 06511. RP ALVES, GA (reprint author), CTR BRASILEIRO PESQUISAS FIS,BR-20000 RIO JANEIRO,BRAZIL. RI Anjos, Joao/C-8335-2013; Alves, Gilvan/C-4007-2013; de Mello Neto, Joao/C-5822-2013 OI de Mello Neto, Joao/0000-0002-3234-6634 NR 13 TC 11 Z9 11 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP R4317 EP R4320 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500001 ER PT J AU GOTSMAN, E LEVIN, EM MAOR, U AF GOTSMAN, E LEVIN, EM MAOR, U TI DIFFRACTIVE DISSOCIATION AND EIKONALIZATION IN HIGH-ENERGY PP AND P(P)OVER-BAR COLLISIONS SO PHYSICAL REVIEW D LA English DT Note ID RISING CROSS-SECTIONS; CERN SPS COLLIDER; ELASTIC-SCATTERING; QCD; ISR AB We show that eikonal corrections imposed on diffraction dissociation processes calculated in the triple Regge limit produce a radical change in the energy dependence of the predicted cross section. The induced correction is shown to be in general agreement with the recent Fermilab Tevatron experimental data. C1 FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. UNIV ILLINOIS,DEPT PHYS,URBANA,IL 61801. RP GOTSMAN, E (reprint author), TEL AVIV UNIV,RAYMOND & BEVERLY SACKLER FAC EXACT SCI,SCH PHYS & ASTRON,IL-69978 TEL AVIV,ISRAEL. NR 44 TC 63 Z9 63 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP R4321 EP R4325 DI 10.1103/PhysRevD.49.R4321 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500002 ER PT J AU HUANG, Z WANG, XN AF HUANG, Z WANG, XN TI CLUSTER STRUCTURE OF DISORIENTED CHIRAL CONDENSATE IN RAPIDITY DISTRIBUTION SO PHYSICAL REVIEW D LA English DT Note ID NUCLEUS-NUCLEUS COLLISIONS; HIGH-ENERGY; PSEUDORAPIDITY DISTRIBUTIONS; MULTIPLICITIES; FIELD AB We study the creation of disoriented chiral condensates with some initial boundary conditions that may be expected in high energy collisions. The equations of motion in the linear sigma model are solved numerically with and without a Lorentz-boost invariance. We suggest that a distinct cluster structure of coherent pion production in the rapidity distribution may emerge due to a quench and may be observed in experiments. C1 LAWRENCE BERKELEY LAB, DIV NUCL SCI, BERKELEY, CA 94720 USA. RP LAWRENCE BERKELEY LAB, THEORET PHYS GRP, MAILSTOP 50A-3115, BERKELEY, CA 94720 USA. NR 26 TC 57 Z9 58 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD MAY 1 PY 1994 VL 49 IS 9 BP R4335 EP R4338 DI 10.1103/PhysRevD.49.R4335 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NK065 UT WOS:A1994NK06500005 ER PT J AU GULACSI, M LEVI, AC TOSATTI, E AF GULACSI, M LEVI, AC TOSATTI, E TI MAPPNG OF CRYSTAL-SURFACES ONTO THE 2-VERTEX MODEL SO PHYSICAL REVIEW E LA English DT Article ID ROUGHENING TRANSITION; PHASE-DIAGRAM; GROWTH; FACES AB Within the solid-on-solid framework we map certain surfaces of a simple cubic crystal onto a five-vertex model. The mapping scheme used differs from the more common body-centered solid-on-solid mapping, which uses a six-vertex model and is only suitable for interfaces whose lattice splits naturally into two sublattices. In the five-vertex model there is no touching of step lines and the arrow-reversal symmetry is broken by construction. After reviewing the exact solution of the five-vertex model and studying its phase diagram in the presence of an external field, we establish an isomorphism between some phases of the vertex model with the (100), (110) and (101BAR) faces of the simple cubic crystal. We determine exactly the mean square height difference. If no field is applied the flat surfaces undergo a transition at a critical temperature, where the inclination of the surfaces begins to change, and roughening sets in. If, however, the inclination is kept constant by applying a suitable field, the low-index flat (or high-index vicinal) surfaces remain smooth (or rough) from zero up to infinite temperature, without undergoing any roughening transition. C1 UNIV GENOA,DIPARTIMENTO FIS,I-16146 GENOA,ITALY. SCUOLA INT SUPER STUDI AVANZATI,I-34014 TRIESTE,ITALY. INT CTR THEORET PHYS,I-34104 TRIESTE,ITALY. RP GULACSI, M (reprint author), LOS ALAMOS NATL LAB,DIV MAGNETISM,LOS ALAMOS,NM 87545, USA. NR 34 TC 3 Z9 3 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP 3843 EP 3851 DI 10.1103/PhysRevE.49.3843 PN A PG 9 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN994 UT WOS:A1994NN99400043 ER PT J AU GERASIMOV, A LEE, SY AF GERASIMOV, A LEE, SY TI RANDOM DRIVING OF A NONLINEAR OSCILLATOR SO PHYSICAL REVIEW E LA English DT Article AB The-evolution equations for the density distribution and its two phase-space point correlation for nonlinear oscillators under the influence of an external random driving force are derived. We found that the correlation function obeys a Fokker-Planck-like evolution equation with decoherence, diffusion, and source terms. An asymptotic steady state solution is discussed, where the small-amplitude and short-wavelength spatial fluctuations of density (''microstructure'') are found to be the special effect of the coherent random driving, distinguishing it from incoherent noise. C1 INDIANA UNIV,DEPT PHYS,BLOOMINGTON,IN 47405. RP GERASIMOV, A (reprint author), FERMILAB NATL ACCELERATOR LAB,POB 500,BATAVIA,IL 60510, USA. NR 9 TC 1 Z9 1 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP 3881 EP 3887 DI 10.1103/PhysRevE.49.3881 PN A PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN994 UT WOS:A1994NN99400047 ER PT J AU FERER, M SMITH, DH AF FERER, M SMITH, DH TI DYNAMICS OF GROWING INTERFACES FROM THE SIMULATION OF UNSTABLE FLOW IN RANDOM-MEDIA SO PHYSICAL REVIEW E LA English DT Article ID POROUS-MEDIA; GROWTH; NOISE; MODELS AB Viscous fingering in random porous media is encountered in many applications of two-phase flow, where the interface is unstable because the ratio of the viscosity of the displaced fluid to that of the injected fluid is large. In these applications, including enhanced oil recovery, characterization of the width of the interface is an important concern. In the limit of stable flow, the interfacial width had been found to grow as w almost-equal-to t(beta), where beta almost-equal-to 0.66, approximately independent of capillary number. To study the same behavior for the unstable case, we have simulated flow in two-dimensional random porous media using a standard model with different viscosity ratios and zero capillary pressure. When the injected fluid has zero viscosity, viscosity ratio M = infinity, the interfacial width has the expected self-similar diffusion-limited-aggregation-like behavior. For smaller viscosity ratios, the flow is self-affine with beta = 0.66 +/- 0.04, which is the same value that had been observed in studies of stable flow. Furthermore, the crossover from self-similar fractal flow to self-affine fractal flow is observed to scale with the same ''characteristic'' time, tau = M0.17, that had been found to scale the average interface position. This ''fractal'' scaling of the crossover leads to definite predictions about the viscosity-ratio dependence of the amplitudes associated with interfacial position and interfacial width. C1 US DOE,MORGANTOWN ENERGY TECHNOL CTR,MORGANTOWN,WV 26507. RP FERER, M (reprint author), W VIRGINIA UNIV,DEPT PHYS,POB 6315,MORGANTOWN,WV 26506, USA. NR 25 TC 21 Z9 21 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP 4114 EP 4120 DI 10.1103/PhysRevE.49.4114 PN A PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN994 UT WOS:A1994NN99400072 ER PT J AU PEURRUNG, AJ KOUZES, RT AF PEURRUNG, AJ KOUZES, RT TI LONG-TERM COHERENCE OF THE CYCLOTRON MODE IN A TRAPPED ION CLOUD SO PHYSICAL REVIEW E LA English DT Article ID RESONANCE MASS-SPECTROMETRY; PURE ELECTRON PLASMAS; NONNEUTRAL PLASMAS; EQUILIBRIA; SPECTRA; THEOREM; NUMBER; COLUMN; MOTION; SHIFT AB An entire family of mass spectrometers relies on the excitation and subsequent detection of the cyclotron mode in a trapped ion cloud. The observed long-term coherence of this mode is critical to the success of these instruments. This paper analyzes the dynamics of the charge cloud after excitation and finds that they are mathematically equivalent to the dynamics of the cloud before excitation. A vortex-like rotation of the cloud prevents expansion under many conditions depending on the trap geometry and the properties of the cloud. The stability of an excited ion cloud with velocity dispersion and applied shear is analyzed and numerical predictions of relevance for ion cyclotron mass spectroscopy are made. RP PEURRUNG, AJ (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 33 TC 28 Z9 28 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP 4362 EP 4368 DI 10.1103/PhysRevE.49.4362 PN B PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN995 UT WOS:A1994NN99500008 ER PT J AU BENAGE, JF SHANAHAN, WR SHERWOOD, EG JONES, LA TRAINOR, RJ AF BENAGE, JF SHANAHAN, WR SHERWOOD, EG JONES, LA TRAINOR, RJ TI MEASUREMENT OF THE ELECTRICAL-RESISTIVITY OF A DENSE STRONGLY COUPLED PLASMA SO PHYSICAL REVIEW E LA English DT Article ID ONE-COMPONENT PLASMA; CONDUCTIVITY; TEMPERATURE AB We present measurements of the electrical resistivity of a dense strongly coupled plasma. This plasma is created in a comprehensively diagnosed capillary discharge that produces uniform well-characterized dense plasmas. Data for polyurethane at densities rho = 0.01rho0, where rho0 = 1.265 g/cm3, and temperatures in the 25-30 eV range are compared with several dense plasma theories, and show a significant disagreement. These results are of importance for the modeling of pulsed power experiments and the understanding of transport processes in many astrophysical plasmas. RP BENAGE, JF (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. NR 28 TC 36 Z9 36 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP 4391 EP 4396 DI 10.1103/PhysRevE.49.4391 PN B PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN995 UT WOS:A1994NN99500011 ER PT J AU YU, LH JOHNSON, E LI, D UMSTADTER, D AF YU, LH JOHNSON, E LI, D UMSTADTER, D TI FEMTOSECOND FREE-ELECTRON LASER BY CHIRPED PULSE AMPLIFICATION SO PHYSICAL REVIEW E LA English DT Article ID MULTIPLE-HARMONIC CONVERSION; RARE-GASES; 1064-NM RADIATION; GENERATION; POWER; INTENSITY AB In this work we combine elements of chirped pulse amplification techniques, now familiar in solid-state lasers, with an amplifier based upon a seeded free-electron laser (FEL). The resulting device would produce amplified pulses of unprecedented brevity at wavelengths shorter than can be currently obtained by any tunable laser system. We use a subharmonically seeded FEL to illustrate the concept. Radiation from a Ti:sapphire laser is frequency tripled and stretched optically to provide a coherent seed pulse for the FEL. When coupled to an electron beam inside a magnetic wiggler, the seed radiation introduces an additional energy modulation on the electron bunch, which has been prepared with an energy chirp to match the chirp in the optical pulse. The energy modulated electrons are then spatially bunched in a dispersion magnet and introduced to a wiggler configured to be resonant to a harmonic of the seed laser, providing additional frequency multiplication. The coherent radiation produced by these electrons is amplified as it traverses the wiggler and is recompressed optically. The preservation of phase coherence provided by this scheme results in a device which can yield 4-fs pulses with 0.3 mJ at a central wavelength of ca. 88 nm, easily the shortest duration of amplified pulses produced by any laser. In this paper we discuss various aspects of the concept, including the generation of short pulses, temporal stretching and compression, and potential applications of the device. The phase distortion during the wide bandwidth FEL amplification is discussed in detail, and is shown to be within the bounds required to produce a 4-fs pulse upon compression. C1 UNIV MICHIGAN,CTR ULTRAFAST OPT SCI,ANN ARBOR,MI 48109. RP YU, LH (reprint author), BROOKHAVEN NATL LAB,NATL SYNCHROTRON LIGHT SOURCE,UPTON,NY 11973, USA. RI Umstadter, Donald/A-1581-2016 OI Umstadter, Donald/0000-0002-2182-4346 NR 28 TC 21 Z9 22 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP 4480 EP 4486 DI 10.1103/PhysRevE.49.4480 PN B PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN995 UT WOS:A1994NN99500022 ER PT J AU KIVSHAR, YS GRONBECHJENSEN, N PARMENTIER, RD AF KIVSHAR, YS GRONBECHJENSEN, N PARMENTIER, RD TI KINKS IN THE PRESENCE OF RAPIDLY VARYING PERTURBATIONS SO PHYSICAL REVIEW E LA English DT Article ID SINE-GORDON CHAIN; SOLITONS; DYNAMICS AB The dynamics of sine-Gordon kinks in the presence of rapidly varying periodic perturbations of different physical origins is described analytically and numerically. The analytical approach is based on asymptotic expansions, and it allows one to derive, in a rigorous way, an effective nonlinear equation for the slowly varying field component in any order of the asymptotic procedure as expansions in the small parameter omega-1, omega being the frequency of the rapidly varying ac driving force. Three physically important examples of such a dynamics, i.e., kinks driven by a direct or parametric ac force, and kinks on a rotating and oscillating background, are analyzed in detail. It is shown that in the main order of the asymptotic procedure the effective equation for the slowly varying field component is a renormalized sine-Gordon equation in the case of the direct driving force or rotating (but phase locked to an external ac force) background, and it is the double sine-Gordon equation for the parametric driving force. The properties of the kinks described by the renormalized nonlinear equations are analyzed, and it is demonstrated analytically and numerically which kinds of physical phenomena may be expected in dealing with the renormalized, rather than the unrenormalized, nonlinear dynamics. In particular, we predict several qualitatively new effects which include, e.g., the perturbation-induced internal oscillations of the 2pi kink in a parametrically driven sine-Gordon model, and the generation of kink motion by a pure ac driving force on a rotating C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. UNIV SALERNO,DIPARTIMENTO FIS,I-84081 SALERNO,ITALY. RP KIVSHAR, YS (reprint author), AUSTRALIAN NATL UNIV,CTR OPT SCI,CANBERRA,ACT 0200,AUSTRALIA. NR 17 TC 18 Z9 18 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP 4542 EP 4551 DI 10.1103/PhysRevE.49.4542 PN B PG 10 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN995 UT WOS:A1994NN99500030 ER PT J AU SANCHEZ, A BISHOP, AR DOMINGUEZADAME, F AF SANCHEZ, A BISHOP, AR DOMINGUEZADAME, F TI KINK STABILITY, PROPAGATION, AND LENGTH-SCALE COMPETITION IN THE PERIODICALLY MODULATED SINE-GORDON EQUATION SO PHYSICAL REVIEW E LA English DT Article ID NONLINEAR SCHRODINGER-EQUATION; DYNAMICS; POTENTIALS; SYSTEM; PERTURBATIONS; SOLITONS; WAVES; MODEL AB We have examined the dynamical behavior of the kink solutions of the one-dimensional sine-Gordon equation in the presence of a spatially periodic parametric perturbation. Our study clarifies and extends the currently available knowledge on this and related nonlinear problems in four directions. First, we present the results of a numerical simulation program that are not compatible with the existence of a radiative threshold predicted by earlier calculations. Second, we carry out a perturbative calculation that helps interpret those previous predictions, enabling us to understand in depth our numerical results. Third, we apply the collective coordinate formalism to this system and demonstrate numerically that it reproduces accurately the observed kink dynamics. Fourth, we report on the occurrence of length-scale competition in this system and show how it can be understood by means of linear stability analysis. Finally, we conclude by summarizing the general physical framework that arises from our study. C1 LOS ALAMOS NATL LAB, CTR NONLINEAR STUDIES, LOS ALAMOS, NM 87545 USA. UNIV CARLOS III, ESCUELA POLITECN SUPER, E-28911 LEGANES, SPAIN. UNIV COMPLUTENSE MADRID, FAC FIS, DEPT FIS MAT, E-28040 MADRID, SPAIN. RP SANCHEZ, A (reprint author), LOS ALAMOS NATL LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. RI Sanchez, Angel/A-9229-2008; Dominguez-Adame, Francisco/E-4277-2010 OI Sanchez, Angel/0000-0003-1874-2881; Dominguez-Adame, Francisco/0000-0002-5256-4196 NR 23 TC 22 Z9 22 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP 4603 EP 4615 DI 10.1103/PhysRevE.49.4603 PN B PG 13 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN995 UT WOS:A1994NN99500035 ER PT J AU BATON, SD ROUSSEAUX, C MOUNAIX, P LABAUNE, C LAFONTAINE, B PESME, D RENARD, N GARY, S LOUISJACQUET, M BALDIS, HA AF BATON, SD ROUSSEAUX, C MOUNAIX, P LABAUNE, C LAFONTAINE, B PESME, D RENARD, N GARY, S LOUISJACQUET, M BALDIS, HA TI STIMULATED BRILLOUIN-SCATTERING WITH A 1 PS LASER-PULSE IN A PERFORMED UNDERDENSE PLASMA SO PHYSICAL REVIEW E LA English DT Note ID PARAMETRIC-INSTABILITIES; ELECTROMAGNETIC-WAVES; RAMAN-SCATTERING; LIGHT; WAVELENGTH; BEHAVIOR; DURATION AB An experimental study of stimulated Brillouin scattering (SBS) with a 1 ps laser pulse in a large underdense preformed plasma is presented. It is shown that the SBS reflectivity increases from 10(-4) to 10(-1) as the intensity of the interaction beam rises from 5 x 10(14) to 10(16) W/cm2; for intensities between 10(16) and 10(17) W/CM2, a saturation level at 10% is experimentally established. This experimental result is compared with theoretical estimates of time-integrated SBS reflectivity in the transient phase of the so-called modified decay regime. The latter results are seen to be consistent with the experimental data provided that there exists a nonthermal noise in the plasma depending on the laser intensity. C1 CEA,CTR ETUD LIMEIL VALENTON,F-94195 VILLENEUVE ST GEO,FRANCE. ECOLE POLYTECH,CTR PHYS THEOR,F-91128 PALAISEAU,FRANCE. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. RP BATON, SD (reprint author), ECOLE POLYTECH,UTILISAT LASERS INTENSES LAB,F-91128 PALAISEAU,FRANCE. NR 22 TC 25 Z9 25 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP R3602 EP R3605 PN A PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN994 UT WOS:A1994NN99400014 ER PT J AU BINDER, PM AF BINDER, PM TI FLUCTUATING HYDRODYNAMICS OF THE CLASSICAL ELECTRON-GAS SO PHYSICAL REVIEW E LA English DT Note ID STATIONARY RANDOM-MEDIA; LONG-TIME TAILS; LATTICE GAS; LORENTZ GAS; DIFFUSION; AUTOMATA; TRACER; DISPLACEMENT; FIELD; MODEL AB Fluctuations of the diffusion tensor in a lattice Lorentz gas model are calculated numerically from a sample of mesoscopic-size systems, and used as input in a mode-coupling expression that predicts long-time tail amplitudes. The results are in good agreement with previously published direct measurements of the tail amplitude over a wide range of scatterer concentrations. We argue that the previous, long-standing disagreement between theory and simulations comes from concentration-independent configurational fluctuations in the diffusion tensor, which we have measured separately and which are not taken into account by existing theories. C1 LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP BINDER, PM (reprint author), UNIV OXFORD WOLFSON COLL,OXFORD OX2 6UD,ENGLAND. NR 32 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP R3565 EP R3567 PN A PG 3 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN994 UT WOS:A1994NN99400004 ER PT J AU CIRILLO, M BISHOP, AR GRONBECHJENSEN, N LOMDAHL, PS AF CIRILLO, M BISHOP, AR GRONBECHJENSEN, N LOMDAHL, PS TI TRANSITION FROM QUASI-PERIODICITY TO CHAOS OF A SOLITON OSCILLATOR SO PHYSICAL REVIEW E LA English DT Note ID LONG JOSEPHSON-JUNCTIONS; PHASE-LOCKING; SIGNALS; SYSTEMS; DRIVEN AB We study the properties of the quasiperiodic attractors of the driven and damped sine-Gordon system close to the onset of chaotic dynamics. Our system is a perturbed sine-Gordon equation with ac and dc forcing terms over a finite-size spatial interval. In this system the quasiperiodic trajectories are generated by the incommensurability of the soliton oscillation and external drive frequencies. For increasing values of the ac drive amplitude the attractors of the system, displayed in a spatially averaged Poincare section, present the characteristic folding and mixing properties of the transition to chaos through quasiperiodicity. In the parameter plane that we scan, the basic features of the transition are not dependent upon the particular ac drive amplitude and frequency causing the transition. Analysis of the singularity spectrum f(alpha) of several attractors at the chaotic threshold exhibits general features of the transition. C1 LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. UNIV ROMA TOR VERGATA,DIPARTIMENTO FIS,I-00133 ROME,ITALY. RP CIRILLO, M (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545, USA. NR 21 TC 5 Z9 5 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD MAY PY 1994 VL 49 IS 5 BP R3606 EP R3609 PN A PG 4 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA NN994 UT WOS:A1994NN99400015 ER PT J AU YANG, YM ZHANG, QA SHARP, DH AF YANG, YM ZHANG, QA SHARP, DH TI SMALL AMPLITUDE THEORY OF RICHTMYER-MESHKOV INSTABILITY SO PHYSICS OF FLUIDS LA English DT Article ID RIEMANN PROBLEM; SHOCK-WAVES; REFRACTION; INTERFACE; STABILITY AB This paper presents a new analysis of small amplitude Richtmyer-Meshkov instability. The linear theory for the case of reflected rarefaction waves, a problem not treated in previous work, is formulated and numerically solved. This paper also carries out a systematic comparison of Richtmyer's impulsive model to the small amplitude theory, which has identified domains of agreement as well as disagreement between the two. This comparison includes both the reflected shock and reflected rarefaction cases. Additional key results include the formulation of criteria determining the reflected wave type in terms of preshocked quantities, identification of parameter regimes corresponding to total transmission of the incident wave, discussion of an instability associated with a rarefaction wave, investigation of phase inversions and the related phenomenon of freeze-out, and study of the sensitivity of the numerical solutions to initial conditions. C1 LOS ALAMOS NATL LAB,DIV THEORET,LOS ALAMOS,NM 87545. RP YANG, YM (reprint author), SUNY STONY BROOK,DEPT APPL MATH & STAT,STONY BROOK,NY 11794, USA. OI ZHANG, Qiang /0000-0002-8659-5396 NR 14 TC 119 Z9 121 U1 3 U2 22 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD MAY PY 1994 VL 6 IS 5 BP 1856 EP 1873 DI 10.1063/1.868245 PG 18 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA NH624 UT WOS:A1994NH62400022 ER PT J AU MOORE, JE FISCH, NJ AF MOORE, JE FISCH, NJ TI GUIDING-CENTER EQUATIONS FOR ELECTRONS IN ULTRAINTENSE LASER FIELDS SO PHYSICS OF PLASMAS LA English DT Article ID ACCELERATION; RADIATION AB The guiding-center equations are derived for electrons in arbitrarily intense laser fields also subject to external fields and ponderomotive forces. Exhibiting the relativistic mass increase of the oscillating electrons, a simple frame-invariant equation is shown to govern the behavior of the electrons for sufficiently weak background fields and ponderomotive forces. The parameter regime for which such a formulation is valid is made precise, and some predictions of the equation are checked by numerical simulation. RP MOORE, JE (reprint author), PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,POB 451,PRINCETON,NJ 08543, USA. RI Moore, Joel/O-4959-2016 OI Moore, Joel/0000-0002-4294-5761 NR 20 TC 9 Z9 9 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1105 EP 1116 DI 10.1063/1.870760 PN 1 PG 12 WC Physics, Fluids & Plasmas SC Physics GA NK071 UT WOS:A1994NK07100002 ER PT J AU SOBEHART, JB FARENGO, R AF SOBEHART, JB FARENGO, R TI A SINGULAR PERTURBATION APPROACH TO ION AND ELECTRON CONFINEMENT IN TRAPPING FIELDS SO PHYSICS OF PLASMAS LA English DT Article ID MOTION AB The confinement of ions and electrons by linear and nonlinear fields is studied. It is assumed that both species are perturbed by collisions with a neutral background gas with the resulting energy and momentum transfer between the interacting species. Asymptotic expansions, based on a singular perturbation approach in terms of the momentum exchange during collisions, are used to determine the distribution function of the confined species. C1 COMIS NACL ENERGIA ATOM,DIV FUS NUCL GERENCIA DESARROLLO,RA-1429 BUENOS AIRES,ARGENTINA. RP SOBEHART, JB (reprint author), LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,MS B-258,LOS ALAMOS,NM 87545, USA. NR 14 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1128 EP 1136 PN 1 PG 9 WC Physics, Fluids & Plasmas SC Physics GA NK071 UT WOS:A1994NK07100005 ER PT J AU SIDIKMAN, KL CARRERAS, BA DIAMOND, PH GARCIA, L AF SIDIKMAN, KL CARRERAS, BA DIAMOND, PH GARCIA, L TI THEORY OF ELECTRIC-FIELD CURVATURE EFFECTS ON LONG-WAVELENGTH DRIFT-WAVE TURBULENCE SO PHYSICS OF PLASMAS LA English DT Article ID EDGE TURBULENCE; TOKAMAK; CONFINEMENT AB A simple model of long-wavelength drift waves is used to study the way in which a radial electric-field profile influences the growth and saturation of turbulence. For a fixed external field, the effect of curvature (partial derivative 2E(r)/partial derivative r2) dominates that of shear (partial derivative E(r)/partial derivative r). In the linear regime, both affect the average k(parallel-to) at which ion damping occurs: shear by shifting the eigenmode off the resonant surface and curvature by changing the eigenmode width. Curvature damps more efficiently and also shifts the real frequency of the drift wave, changing the instability drive. In the nonlinear regime, radial trapping at large fluctuation levels limits the ability of an external electric-field profile to affect the spatial structure. Changes in damping are now less effective than the feedback between frequency shift and drive. The importance of the frequency shift caused by electric-field curvature in the presence of finite-amplitude fluctuations has been demonstrated by numerical calculations. C1 UNIV CALIF SAN DIEGO,LA JOLLA,CA 92093. GEN ATOM,SAN DIEGO,CA 92186. UNIV CARLOS III,MADRID,SPAIN. RP SIDIKMAN, KL (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. RI Garcia, Luis/A-5344-2015 OI Garcia, Luis/0000-0002-0492-7466 NR 21 TC 27 Z9 27 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1142 EP 1153 DI 10.1063/1.870765 PN 1 PG 12 WC Physics, Fluids & Plasmas SC Physics GA NK071 UT WOS:A1994NK07100007 ER PT J AU SHAING, KC HSU, CT DOMINGUEZ, N AF SHAING, KC HSU, CT DOMINGUEZ, N TI RESONANCE PARALLEL VISCOSITY IN THE BANANA REGIME IN POLOIDALLY ROTATING TOKAMAK PLASMAS SO PHYSICS OF PLASMAS LA English DT Article ID L-H TRANSITION; TOROIDAL PLASMAS; TRANSPORT-THEORY; SHOCK FORMATION; ELECTRIC-FIELD; JFT-2M TOKAMAK; MODE; FLUCTUATIONS; BIFURCATION; GEOMETRY AB Parallel viscosity in the banana regime in a poloidally (EXB) rotating tokamak plasma is calculated to include the effects of orbit squeezing and to allow the poloidal EXB Mach number M(p) to have a value of order unity. Here, E is the electric field and B is the magnetic field. The effects of orbit squeezing not only modify the size of the particle orbit, but also change the fraction of poloidally trapped particles. Resonance between the particle parallel (to B) speed u and the poloidal component of the EXB velocity can only occur for those particles with energy (v/v(t))2 > M(p)2 (with v the particle speed and v(t) the thermal speed). Thus, the resonance parallel plasma viscosity in the banana regime decreases exponentially with M(p)2 when M(p)2 greater-than-or-equal-to 1, and has a local maximum of M(p)2 approximately 1. C1 MIT,CTR PLASMA FUS,CAMBRIDGE,MA 02139. RP SHAING, KC (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 35 TC 19 Z9 19 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1168 EP 1176 DI 10.1063/1.870713 PN 1 PG 9 WC Physics, Fluids & Plasmas SC Physics GA NK071 UT WOS:A1994NK07100010 ER PT J AU TSIDULKO, YA BERK, HL COHEN, RH AF TSIDULKO, YA BERK, HL COHEN, RH TI INSTABILITY DUE TO AXIAL SHEAR AND SURFACE IMPEDANCE SO PHYSICS OF PLASMAS LA English DT Article ID TURBULENCE AB The stability of plasma flow in the scrape-off layer of a tokamak, taking into account the surface sheath impedance and the axial shear in the EXB flow is analyzed. An interesting stability problem arises in the limit that end plates are sufficiently far apart, so that stability can be analyzed when the plasma is taken to interact with a single end plate. As parameters are varied, windows of instability are found, and it is shown that growth rates are maximized for an insulating end plate and are also quite sensitive to the ratio of the ion diamagnetic and EXB drift frequencies. Mixing-length estimates of the diffusivity are comparable to experimentally observed values. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. BUDKER NUCL PHYS INST,NOVOSIBIRSK,RUSSIA. RP TSIDULKO, YA (reprint author), UNIV TEXAS,INST FUS STUDIES,AUSTIN,TX 78712, USA. NR 15 TC 17 Z9 17 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1199 EP 1213 DI 10.1063/1.870717 PN 1 PG 15 WC Physics, Fluids & Plasmas SC Physics GA NK071 UT WOS:A1994NK07100014 ER PT J AU KAISER, TB COHEN, BI BERGER, RL LASINSKI, BF LANGDON, AB WILLIAMS, EA AF KAISER, TB COHEN, BI BERGER, RL LASINSKI, BF LANGDON, AB WILLIAMS, EA TI LANDAU-FLUID SIMULATION OF LASER FILAMENTATION SO PHYSICS OF PLASMAS LA English DT Article ID PLASMAS AB The Landau-fluid model is a recently introduced fluid-moment closure scheme [G. W. Hammett and F. W. Perkins, Phys. Rev. Lett. 64, 3019 (1990)] that was designed to include kinetic dissipative effects like Landau damping in fluid calculations. The fluid-moment hierarchy is terminated by assuming linear relationships among the retained moments in Fourier-transform space, with coefficients determined by matching the plasma response to that obtained from a kinetic analysis. This paper generalizes the technique to the full range of ion and electron collisionality and applies it to a new fluid simulation code constructed to study laser filamentation in underdense plasmas [Berger et al., Phys. Fluids B 5, 2243 (1993)]. By matching the ion-acoustic complex frequency derived from the fluid model with that predicted by collisional, Fokker-Planck, and kinetic analyses, the specific heat ratio, thermal conductivity coefficient, and viscosity coefficient for ions and the thermal conductivity coefficient for electrons are determined as functions of the wave number k. For frequencies much less than the pump frequency this leads to a fourth-order polynomial dispersion relation whose spectrum includes damped ion-acoustic waves as well as filamentation modes whose stability depends on the pump strength. An analytic instability threshold condition on the laser intensity is derived from which the relative importance of ponderomotive and thermal drives can be assessed. Expressions for the linear susceptibilities in the presence of a finite-amplitude pump are also given, which might prove useful for understanding spectral linewidths for Thomson scattering. RP KAISER, TB (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 20 TC 28 Z9 28 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1287 EP 1302 DI 10.1063/1.870727 PN 1 PG 16 WC Physics, Fluids & Plasmas SC Physics GA NK071 UT WOS:A1994NK07100024 ER PT J AU QIAN, Q DAVIDSON, RC CHEN, CP AF QIAN, Q DAVIDSON, RC CHEN, CP TI CHAOTIC PARTICLE DYNAMICS IN A PERIODIC FOCUSING QUADRUPOLE MAGNETIC-FIELD SO PHYSICS OF PLASMAS LA English DT Article AB The Hamiltonian for a test particle is used to study the two-dimensional transverse particle dynamics in a non-neutral charged particle beam propagating through a periodic quadrupole focusing field. The self-electric and self-magnetic fields produced by the beam space charge and current are taken into account. The Lie point-symmetry group method and Noether's theorem are applied to study the integrability of the equations of motion. It is concluded that the particle orbits are regular only for the case of a uniform density beam, and become chaotic when the beam density is nonuniform. Numerical computations, including Poincare surface-of-section plots and Lyapunov exponents, have been performed to confirm the analytical results. A new numerical scheme, called the numerical irreversibility method, is proposed as an alternative approach to determine the integrability of Hamiltonian systems. C1 MIT,CTR PLASMA FUS,CAMBRIDGE,MA 02139. RP QIAN, Q (reprint author), PRINCETON UNIV,PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 26 TC 6 Z9 7 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1328 EP 1337 DI 10.1063/1.870731 PN 1 PG 10 WC Physics, Fluids & Plasmas SC Physics GA NK071 UT WOS:A1994NK07100028 ER PT J AU BERGER, RL LASINSKI, BF KAISER, TB WILLIAMS, EA LANGDON, AB COHEN, BI AF BERGER, RL LASINSKI, BF KAISER, TB WILLIAMS, EA LANGDON, AB COHEN, BI TI THEORY AND 3-DIMENSIONAL SIMULATION OF LIGHT FILAMENTATION IN LASER-PRODUCED PLASMAS - COMMENT SO PHYSICS OF PLASMAS LA English DT Note RP BERGER, RL (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 7 TC 0 Z9 0 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1366 EP 1368 DI 10.1063/1.870738 PN 1 PG 3 WC Physics, Fluids & Plasmas SC Physics GA NK071 UT WOS:A1994NK07100035 ER PT J AU SHAING, KC AF SHAING, KC TI TEST OF TOKAMAK LOW-MODE-HIGH-MODE TRANSITION THEORY IN STELLARATORS (VOL 5, PG 3841, 1993) SO PHYSICS OF PLASMAS LA English DT Correction, Addition RP SHAING, KC (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1373 EP 1373 DI 10.1063/1.870946 PN 1 PG 1 WC Physics, Fluids & Plasmas SC Physics GA NK071 UT WOS:A1994NK07100038 ER PT J AU KILKENNY, JD GLENDINNING, SG HAAN, SW HAMMEL, BA LINDL, JD MUNRO, D REMINGTON, BA WEBER, SV KNAUER, JP VERDON, CP AF KILKENNY, JD GLENDINNING, SG HAAN, SW HAMMEL, BA LINDL, JD MUNRO, D REMINGTON, BA WEBER, SV KNAUER, JP VERDON, CP TI A REVIEW OF THE ABLATIVE STABILIZATION OF THE RAYLEIGH-TAYLOR INSTABILITY IN REGIMES RELEVANT TO INERTIAL CONFINEMENT FUSION SO PHYSICS OF PLASMAS LA English DT Review ID INDUCED SPATIAL INCOHERENCE; HYDRODYNAMIC INSTABILITIES; NUMERICAL-SIMULATION; LASER-BEAM; LARGE GROWTH; TARGETS; PLASMA; NOVA AB It has been recognized for many years that the most significant limitation of inertial confinement fusion (ICF) is the Rayleigh-Taylor (RT) instability. it limits the distance an ablatively driven shell can be moved to several times its initial thickness. Fortunately material flow through the unstable region at velocity v(A) reduces the growth rate to square-root kg/1+kL-betakv(A) with beta from 2-3. In recent years experiments using both x-ray drive and smoothed laser drive to accelerate foils have confirmed the community's understanding of the ablative RT instability in planar geometry. The growth of small initial modulations on the foils is measured for growth factors up to 60 for direct drive and 80 for indirect drive. For x-ray drive large stabilization is evident. After some growth, the instability enters the nonlinear phase when mode coupling and saturation are also seen and compare well with modeling. Normalized growth rates for direct drive are measured to be higher, but strategies for reduction by raising the isentrope are being investigated. For direct drive, high spatial frequencies are imprinted from the laser beam and amplified by the RT instability. Modeling shows an understanding of this ''laser imprinting.'' C1 UNIV ROCHESTER,LASER ENGN LAB,ROCHESTER,NY 14620. RP KILKENNY, JD (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 56 TC 142 Z9 151 U1 6 U2 30 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1379 EP 1389 DI 10.1063/1.870688 PN 2 PG 11 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200002 ER PT J AU PARKER, SE DORLAND, W SANTORO, RA BEER, MA LIU, QP LEE, WW HAMMETT, GW AF PARKER, SE DORLAND, W SANTORO, RA BEER, MA LIU, QP LEE, WW HAMMETT, GW TI COMPARISONS OF GYROFLUID AND GYROKINETIC SIMULATIONS SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID POLOIDAL FLOW GENERATION; PARTICLE SIMULATION; DRIFT INSTABILITIES; TFTR TOKAMAK; TURBULENCE; EQUATIONS; TRANSPORT; PLASMA; MODELS AB The gyrokinetic and gyrofluid models show the most promise for large scale simulations of tokamak microturbulence. This paper discusses detailed comparisons of these two complementary approaches. Past comparisons with linear theory have been fairly good, therefore the emphasis here is on nonlinear comparisons. Simulations include simple two-dimensional slab test cases, turbulent three-dimensional slab cases, and toroidal cases, each modeling the nonlinear evolution of the ion temperature gradient instability. There is good agreement in both turbulent and coherent nonlinear slab comparisons in terms of the ion heat flux, both in magnitude and scaling with magnetic shear. However, the nonlinear saturation level for \PHI\ in the slab comparisons shows differences of approximately 40%. Preliminary toroidal comparisons show agreement within 50%, in terms of ion heat flux and saturation level. RP PARKER, SE (reprint author), PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,POB 451,PRINCETON,NJ 08543, USA. RI Hammett, Gregory/D-1365-2011; Dorland, William/B-4403-2009 OI Hammett, Gregory/0000-0003-1495-6647; Dorland, William/0000-0003-2915-724X NR 40 TC 44 Z9 44 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1461 EP 1469 DI 10.1063/1.870696 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200010 ER PT J AU ZWEBEN, SJ BUSH, CE CHANG, CS CHANG, Z DARROW, DS FREDRICKSON, ED HERRMANN, HW MYNICK, HE SCHIVELL, J BELL, M BOIVIN, R BUDNY, RV CHENG, CZ ERNST, D HAMMETT, G JOHNSON, LC MCCUNE, D MURAKAMI, M OWENS, DK PARK, J PHILLIPS, CK REDI, MH SCOTT, S STRACHAN, JD TAYLOR, G TUSZEWSKI, M WHITE, RB WILSON, JR ZARNSTORFF, M AF ZWEBEN, SJ BUSH, CE CHANG, CS CHANG, Z DARROW, DS FREDRICKSON, ED HERRMANN, HW MYNICK, HE SCHIVELL, J BELL, M BOIVIN, R BUDNY, RV CHENG, CZ ERNST, D HAMMETT, G JOHNSON, LC MCCUNE, D MURAKAMI, M OWENS, DK PARK, J PHILLIPS, CK REDI, MH SCOTT, S STRACHAN, JD TAYLOR, G TUSZEWSKI, M WHITE, RB WILSON, JR ZARNSTORFF, M TI ANOMALOUS LOSSES OF DEUTERIUM DEUTERIUM FUSION PRODUCTS IN THE TOKAMAK FUSION TEST REACTOR SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID TFTR TOKAMAK; FAST IONS; CONFINEMENT AB In the Tokamak Fusion Test Reactor (TFTR) [International Conference on Plasma Physics and Controlled Nuclear Fusion Research, Wurzburg, Paper No. A-2-2 (International Atomic Energy Agency, Vienna, 1993)] there have been at least three types of anomalous loss of alpha-like deuterium-deuterium (D-D) fusion products: (1) a magnetohydrodynamic (MHD)-induced loss of D-D fusion products correlated with Mirnov and fishbone-type oscillations and sawtooth crashes, (2) a slow ''delayed'' loss of partially thermalized D-D fusion products occurring without large MHD activity, and (3) ion cyclotron resonance heating (ICRH)-induced loss of D-D fusion products ions observed during direct electron heating experiments, and possibly also during He-3 minority heating. In this paper each of these will be reviewed, concentrating on those due to MHD activity, which are the largest of these anomalous losses. The experimental results are compared with numerical models of various fusion product transport mechanisms. RP ZWEBEN, SJ (reprint author), PRINCETON PLASMA PHYS LAB,POB 451,PRINCETON,NJ 08543, USA. RI Hammett, Gregory/D-1365-2011; Ernst, Darin/A-1487-2010; White, Roscoe/D-1773-2013; Cheng, Chio/K-1005-2014 OI Hammett, Gregory/0000-0003-1495-6647; Ernst, Darin/0000-0002-9577-2809; White, Roscoe/0000-0002-4239-2685; NR 31 TC 27 Z9 27 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1469 EP 1478 DI 10.1063/1.870697 PN 2 PG 10 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200011 ER PT J AU SPONG, DA CARRERAS, BA HEDRICK, CL AF SPONG, DA CARRERAS, BA HEDRICK, CL TI NONLINEAR EVOLUTION OF THE TOROIDAL ALFVEN INSTABILITY USING A GYROFLUID MODEL SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID ENERGETIC TRAPPED-PARTICLES; INTERNAL KINK MODES; BALLOONING MODES; ALPHA-PARTICLES; EXCITATION; TOKAMAKS; TURBULENCE; EIGENMODES; EQUATIONS; PLASMAS AB Discrete shear Alfven modes such as the TAE (toroidal Alfven eigenmode) are susceptible to destabilization by energetic alpha populations and neutral beams; this can lead to enhanced fast ion losses and degraded heating efficiencies. A gyrofluid model with Landau closure has been developed for understanding both the linear and nonlinear phases of these instabilities. The linear wave-particle resonances necessary to excite Alfven instabilities are included in a coupled set of fluid equations. This model is used to analyze several nonlinear saturation mechanisms that arise from mode coupling effects. The effects of shear flow velocity generation (through the Reynolds stress) and localized current generation (leading to modifications in the q profile) are specifically examined. RP SPONG, DA (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. RI Spong, Donald/C-6887-2012 OI Spong, Donald/0000-0003-2370-1873 NR 35 TC 48 Z9 48 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1503 EP 1510 DI 10.1063/1.870700 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200015 ER PT J AU POLITZER, PA CASPER, T FOREST, CB GOHILL, P HEIDBRINK, WW HYATT, AW JAMES, RA JONG, R LAO, LL MAKOWSKI, M MEYER, W PORTER, GD SAGER, GT STALLARD, BW STJOHN, H THOMPSON, SJ TURNBULL, AD WROBLEWSKI, D AF POLITZER, PA CASPER, T FOREST, CB GOHILL, P HEIDBRINK, WW HYATT, AW JAMES, RA JONG, R LAO, LL MAKOWSKI, M MEYER, W PORTER, GD SAGER, GT STALLARD, BW STJOHN, H THOMPSON, SJ TURNBULL, AD WROBLEWSKI, D TI EVOLUTION OF HIGH BETA-P PLASMAS WITH IMPROVED STABILITY AND CONFINEMENT SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID TOKAMAKS AB Experiments to explore the long-time evolution of noninductive, high beta(p) plasmas in the DIII-D tokamak [Plasma Physics and Controlled Nuclear Fusion Research, 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. 1, p. 159], have identified a new, quiescent, high performance regime. The experiments were carried out at low current (400-800 kA) with medium power neutral beam injection (3-10 MW). This regime is characterized by high q0 ( > 2) and moderate l(i)(approximately 1.3). It is reached by slow relaxation of the current profile, on the resistive time scale. As the profiles relax, q0 rises and l(i) falls. When q0 goes above 2 (approximately), magnetohydrodynamic (MHD) activity disappears, and the stored energy rises. Most dramatic is the strong peaking of the central density, which increases by as much as a factor of 2. The improved central confinement appears similar to the PEP/reversed central shear/second stable core modes seen in tokamak experiments, but in this case without external intervention or transient excitation. At high current, a similar, but slower relaxation is seen. Also notable in connection with these discharges is the behavior of the edge and scrape-off layer (SOL). The edge localized modes (ELM's) as seen previously, are small and very rapid (to 1 kHz). The SOL exhibits high density (greater-than-or-equal-to 1 X 101(9) m-3), which shows little or no falloff with radius. Also the power deposition at the divertor surface is very broad, up to four times the width usually seen. This regime is of particular interest for the development of steady-state tokamak operating scenarios, for the Tokamak Physics Experiment (TPX), and following reactors. C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. UNIV CALIF IRVINE,IRVINE,CA 92717. RP POLITZER, PA (reprint author), GEN ATOM,POB 85608,SAN DIEGO,CA 92186, USA. NR 18 TC 34 Z9 34 U1 1 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1545 EP 1553 DI 10.1063/1.870937 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200021 ER PT J AU HAWRYLUK, RJ ADLER, H ALLING, P ANCHER, C ANDERSON, H ANDERSON, JL ANDERSON, JW ARUNASALAM, V ASCIONE, G ASCHROFT, D BARNES, CW BARNES, G BATCHELOR, DB BATEMAN, G BATHA, S BAYLOR, LA BEER, M BELL, MG BIGLOW, TS BITTER, M BLANCHARD, W BONOLI, P BRETZ, NL BRUNKHORST, C BUDNY, R BURGESS, T BUSH, H BUSH, CE CAMP, R CAORLIN, M CARNEVALE, H CHANG, Z CHEN, L CHENG, CZ CHRZANOWSKI, J COLLAZO, I COLLINS, J COWARD, G COWLEY, S CROPPER, M DARROW, DS DAUGERT, R DELOOPER, J DUONG, H DUDEK, L DURST, R EFTHIMION, PC ERNST, D FAUNCE, J FONCK, RJ FREDD, E FREDRICKSON, E FROMM, N FU, GY FURTH, HP GARZOTTO, V GENTILE, C GETTELFINGER, G GILBERT, J GIOIA, J GOLDFINGER, RC GOLIAN, T GORELENKOV, N GOUGE, MJ GREK, B GRISHAM, LR HAMMETT, G HANSON, GR HEIDBRINK, W HERMANN, HW HILL, KW HIRSHMAN, S HOFFMAN, DJ HOSEA, J HULSE, RA HSUAN, H JAEGER, EF JANOS, A JASSBY, DL JOBES, FC JOHNSON, DW JOHNSON, LC KAMPERSCHROER, J KESNER, J KUGEL, H KWON, S LABIK, G LAM, NT LAMARCHE, PH LAUGHLIN, MJ LAWSON, E LEBLANC, B LEONARD, M LEVINE, J LEVINTON, FM LOESSER, D LONG, D MACHUZAK, J MANSFIELD, DE MARCHLIK, M MARMAR, ES MARSALA, R MARTIN, A MARTIN, G MASTROCOLA, V MAZZUCATO, E MCCARTHY, MP MAJESKI, R MAUEL, M MCCORMACK, B MCCUNE, DC MCGUIRE, KM MEADE, DM MEDLEY, SS MIKKELSEN, DR MILORA, SL MONTICELLO, D MUELLER, D MURAKAMI, M MURPHY, JA NAGY, A NAVRATIL, GA NAZIKIAN, R NEWMAN, R NISHITANI, T NORRIS, M OCONNOR, T OLDAKER, M ONGENA, J OSAKABE, M OWENS, DK PARK, H PARK, W PAUL, SF PAVLOV, YI PEARSON, G PERKINS, F PERRY, E PERSING, R PETROV, M PHILLIPS, CK PITCHER, S POPOVICHEV, S QUALLS, AL RAFTOPOULOS, S RAMAKRISHNAN, R RAMSEY, A RASMUSSEN, DA REDI, MH RENDA, G REWOLDT, G ROBERTS, D ROGERS, J ROSSMASSLER, R ROQUEMORE, AL SABBAGH, SA SASAO, M SCHARER, J SCHILLING, G SCHIVELL, J SCHMIDT, GL SCILLIA, R SCOTT, SD SENKO, T SISSINGH, R SKINNER, C SNIPES, J SNOOK, P STENCEL, J STEVENS, J STEVENSON, T STRATTON, BC STRACHAN, JD STODIEK, W SWANSON, J SYNAKOWSKI, E TANG, W TAYLOR, G TERRY, J THOMPSON, ME TIMBERLAKE, JR TOWNER, HH ULRICKSON, M VONHALLE, A VANNOY, C WIELAND, R WILGEN, JB WILLIAMS, M WILSON, JR WRIGHT, K WONG, D WONG, KL WOSKOV, P WURDEN, GA YAMADA, M YEUN, A YOSHIKAWA, S YOUNG, KM ZAKHAROV, L ZARNSTORFF, MC ZWEBEN, SJ AF HAWRYLUK, RJ ADLER, H ALLING, P ANCHER, C ANDERSON, H ANDERSON, JL ANDERSON, JW ARUNASALAM, V ASCIONE, G ASCHROFT, D BARNES, CW BARNES, G BATCHELOR, DB BATEMAN, G BATHA, S BAYLOR, LA BEER, M BELL, MG BIGLOW, TS BITTER, M BLANCHARD, W BONOLI, P BRETZ, NL BRUNKHORST, C BUDNY, R BURGESS, T BUSH, H BUSH, CE CAMP, R CAORLIN, M CARNEVALE, H CHANG, Z CHEN, L CHENG, CZ CHRZANOWSKI, J COLLAZO, I COLLINS, J COWARD, G COWLEY, S CROPPER, M DARROW, DS DAUGERT, R DELOOPER, J DUONG, H DUDEK, L DURST, R EFTHIMION, PC ERNST, D FAUNCE, J FONCK, RJ FREDD, E FREDRICKSON, E FROMM, N FU, GY FURTH, HP GARZOTTO, V GENTILE, C GETTELFINGER, G GILBERT, J GIOIA, J GOLDFINGER, RC GOLIAN, T GORELENKOV, N GOUGE, MJ GREK, B GRISHAM, LR HAMMETT, G HANSON, GR HEIDBRINK, W HERMANN, HW HILL, KW HIRSHMAN, S HOFFMAN, DJ HOSEA, J HULSE, RA HSUAN, H JAEGER, EF JANOS, A JASSBY, DL JOBES, FC JOHNSON, DW JOHNSON, LC KAMPERSCHROER, J KESNER, J KUGEL, H KWON, S LABIK, G LAM, NT LAMARCHE, PH LAUGHLIN, MJ LAWSON, E LEBLANC, B LEONARD, M LEVINE, J LEVINTON, FM LOESSER, D LONG, D MACHUZAK, J MANSFIELD, DE MARCHLIK, M MARMAR, ES MARSALA, R MARTIN, A MARTIN, G MASTROCOLA, V MAZZUCATO, E MCCARTHY, MP MAJESKI, R MAUEL, M MCCORMACK, B MCCUNE, DC MCGUIRE, KM MEADE, DM MEDLEY, SS MIKKELSEN, DR MILORA, SL MONTICELLO, D MUELLER, D MURAKAMI, M MURPHY, JA NAGY, A NAVRATIL, GA NAZIKIAN, R NEWMAN, R NISHITANI, T NORRIS, M OCONNOR, T OLDAKER, M ONGENA, J OSAKABE, M OWENS, DK PARK, H PARK, W PAUL, SF PAVLOV, YI PEARSON, G PERKINS, F PERRY, E PERSING, R PETROV, M PHILLIPS, CK PITCHER, S POPOVICHEV, S QUALLS, AL RAFTOPOULOS, S RAMAKRISHNAN, R RAMSEY, A RASMUSSEN, DA REDI, MH RENDA, G REWOLDT, G ROBERTS, D ROGERS, J ROSSMASSLER, R ROQUEMORE, AL SABBAGH, SA SASAO, M SCHARER, J SCHILLING, G SCHIVELL, J SCHMIDT, GL SCILLIA, R SCOTT, SD SENKO, T SISSINGH, R SKINNER, C SNIPES, J SNOOK, P STENCEL, J STEVENS, J STEVENSON, T STRATTON, BC STRACHAN, JD STODIEK, W SWANSON, J SYNAKOWSKI, E TANG, W TAYLOR, G TERRY, J THOMPSON, ME TIMBERLAKE, JR TOWNER, HH ULRICKSON, M VONHALLE, A VANNOY, C WIELAND, R WILGEN, JB WILLIAMS, M WILSON, JR WRIGHT, K WONG, D WONG, KL WOSKOV, P WURDEN, GA YAMADA, M YEUN, A YOSHIKAWA, S YOUNG, KM ZAKHAROV, L ZARNSTORFF, MC ZWEBEN, SJ TI PREPARATIONS FOR DEUTERIUM-TRITIUM EXPERIMENTS ON THE TOKAMAK FUSION TEST REACTOR .3. SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID ALFVEN EIGENMODES; ALPHA-PARTICLES; TFTR AB The final hardware modifications for tritium operation have been completed for the Tokamak Fusion Test Reactor (TFTR) [Fusion Technol. 21, 1324 (1992)]. These activities include preparation of the tritium gas handling system, installation of additional neutron shielding, conversion of the toroidal field coil cooling system from water to a Fluorinert(TM) system, modification of the vacuum system to handle tritium, preparation, and testing of the neutral beam system for tritium operation and a final deuterium-deuterium (D-D) run to simulate expected deuterium-tritium (D-T) operation. Testing of the tritium system with low concentration tritium has successfully begun. Simulation of trace and high power D-T experiments using D-D have been performed. The physics objectives of D-T operation are production of almost-equal-to 10 MW of fusion power, evaluation of confinement, and heating in deuterium-tritium plasmas, evaluation of a-particle heating of electrons, and collective effects driven by alpha particles and testing of diagnostics for confined a particles. Experimental results and theoretical modeling in support of the D-T experiments are reviewed. RP HAWRYLUK, RJ (reprint author), PRINCETON UNIV,PLASMA PHYS LAB,POB 451,PRINCETON,NJ 08543, USA. RI Cheng, Chio/K-1005-2014; Yamada, Masaaki/D-7824-2015; Wurden, Glen/A-1921-2017; Sabbagh, Steven/C-7142-2011; Hammett, Gregory/D-1365-2011; Ernst, Darin/A-1487-2010; chen, liu/I-2297-2013 OI Yamada, Masaaki/0000-0003-4996-1649; Wurden, Glen/0000-0003-2991-1484; Mauel, Michael/0000-0003-2490-7478; Hammett, Gregory/0000-0003-1495-6647; Ernst, Darin/0000-0002-9577-2809; NR 27 TC 7 Z9 7 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1560 EP 1567 DI 10.1063/1.870707 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200023 ER PT J AU NEWMAN, DE TERRY, PW DIAMOND, PH LIANG, YM CRADDOCK, GG KONIGES, AE CROTTINGER, JA AF NEWMAN, DE TERRY, PW DIAMOND, PH LIANG, YM CRADDOCK, GG KONIGES, AE CROTTINGER, JA TI THE DYNAMICS OF LONG-WAVELENGTH ELECTROSTATIC TURBULENCE IN TOKAMAKS SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID CONVECTIVE-CELL TURBULENCE AB From extensive simulation of simple local fluid models of long wavelength drift wave turbulence in tokamaks, it is found that conventional notions concerning directions of cascades, locality and isotropy of spectral transfer, frequencies of fluctuations, and stationarity of saturation do not hold for moderate to long wavelengths (kp(s) less-than-or-equal-to 1). In particular, at long wavelengths, where spectral transfer of energy is dominated by the E X B nonlinearity, energy is carried to short scale (even in two dimensions) in a manner that is anisotropic and highly nonlocal (energy is efficiently passed between modes separated by the entire spectrum range in a correlation time). At short wavelengths, transfer is dominated by the polarization drift nonlinearity. While the standard dual cascade applies in this subrange, it is found that finite spectrum size can produce cascades that are reverse directed (i.e., energy to high k) and are nonconservative in enstrophy and energy similarity ranges (but conservative overall). In regions where both nonlinearities are important, cross-coupling between the nonlinearities gives rise to large nonlinear frequency shifts which profoundly affect the dynamics of saturation by modifying the growth rate and nonlinear transfer rates. These modifications produce a nonstationary saturated state with large amplitude, long period relaxation oscillations in the energy, spectrum shape, and transport rates. Methods of observing these effects are presented. C1 UNIV WISCONSIN,DEPT PHYS,MADISON,WI 53706. UNIV CALIF SAN DIEGO,DEPT PHYS,LA JOLLA,CA 92093. LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. NR 12 TC 17 Z9 17 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1592 EP 1600 DI 10.1063/1.870935 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200027 ER PT J AU MANICKAM, J CHANCE, MS JARDIN, SC KESSEL, C MONTICELLO, D POMPHREY, N REIMAN, A WANG, C ZAKHAROV, LE AF MANICKAM, J CHANCE, MS JARDIN, SC KESSEL, C MONTICELLO, D POMPHREY, N REIMAN, A WANG, C ZAKHAROV, LE TI THE PROSPECTS FOR MAGNETOHYDRODYNAMIC STABILITY IN ADVANCED TOKAMAK REGIMES SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID MHD AB Stability analysis of advanced regime tokamaks is presented. Here advanced regimes are defined to include configurations where the ratio of the bootstrap current, I(BS), to the total plasma current, I(p), approaches unity, and the normalized stored energy, beta(N)* = 80pi[p2]1/2a/I(p)B0, has a value greater than 4.5. Here, p is the plasma pressure, a the minor radius in meters, I(p) is in mega-amps, B0 is the magnetic field in Tesla, and [.] represents a volume average. Specific scenarios are discussed in the context of Toroidal Physics Experiment (TPX) [Proceedings of the 20th European Physical Society Conference on Controlled Fusion and Plasma Physics, Lisbon, 1993, edited by J. A. Costa Cabral, M. E. Manso, F. M. Serra, and F. C. Schuller (European Physical Society, Petit-Lancy, 1993), p. 1-80]. The best scenario is one with reversed shear, in the q profile, in the central region of the tokamak. The bootstrap current obtained from the plasma profiles provides 90% of the required current, and is well aligned with the optimal current profile for ideal magnetohydrodynamic stability. This configuration is stable up to beta(N)* almost-equal-to 6.8, if the external boundary conditions are relaxed to those corresponding to an ideal structure at a moderate distance of approximately 1.3 times the minor radius. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP MANICKAM, J (reprint author), PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. RI Jardin, Stephen/E-9392-2010; pomphrey, neil/G-4405-2010 NR 16 TC 64 Z9 64 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1601 EP 1605 DI 10.1063/1.870660 PN 2 PG 5 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200028 ER PT J AU RICHARDS, B UCKAN, T WOOTTON, AJ CARRERAS, BA BENGTSON, RD HURWITZ, P LI, GX LIN, H ROWAN, WL TSUI, HYW SEN, AK UGLUM, J AF RICHARDS, B UCKAN, T WOOTTON, AJ CARRERAS, BA BENGTSON, RD HURWITZ, P LI, GX LIN, H ROWAN, WL TSUI, HYW SEN, AK UGLUM, J TI MODIFICATION OF TOKAMAK EDGE TURBULENCE USING FEEDBACK SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID SPECTRA AB Using active feedback, the turbulent fluctuation levels have been reduced by as much as a factor of 2 in the edge of the Texas Experimental Tokamak (TEXT) [K. W. Gentle, Nucl. Fusion Technol. 1, 479 (1981)]. A probe system was used to drive a suppressor wave in the TEXT limiter shadow. A decrease in the local turbulence-induced particle flux has been seen, but a global change in the particle transport at the present time has not been observed. By changing the phase shift and gain of the feedback network, the amplitude of the turbulence was increased by a factor of 10. C1 OAK RIDGE NATL LAB,DIV FUS ENERGY,OAK RIDGE,TN 37831. UNIV TEXAS,FUS RES CTR,AUSTIN,TX 78712. OAK RIDGE NATL LAB,DIV FUS ENERGY,OAK RIDGE,TN 37831. AUBURN UNIV,DEPT PHYS,AUBURN,AL 36849. COLUMBIA UNIV,PLASMA PHYS LAB,NEW YORK,NY 10027. RP RICHARDS, B (reprint author), UNIV TEXAS,FUS RES CTR,AUSTIN,TX 78712, USA. NR 22 TC 21 Z9 24 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1606 EP 1611 DI 10.1063/1.870661 PN 2 PG 6 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200029 ER PT J AU TABAK, M HAMMER, J GLINSKY, ME KRUER, WL WILKS, SC WOODWORTH, J CAMPBELL, EM PERRY, MD MASON, RJ AF TABAK, M HAMMER, J GLINSKY, ME KRUER, WL WILKS, SC WOODWORTH, J CAMPBELL, EM PERRY, MD MASON, RJ TI IGNITION AND HIGH-GAIN WITH ULTRAPOWERFUL LASERS SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID RAYLEIGH-TAYLOR INSTABILITY; ABSORPTION; PLASMAS; PULSES; TARGETS; FUSION; MODEL AB Ultrahigh intensity lasers can potentially be used in conjunction with conventional fusion lasers to ignite inertial confinement fusion (ICF) capsules with a total energy of a few tens of kilojoules of laser light, and can possibly lead to high gain with as little as 100 kJ. A scheme is proposed with three phases. First, a capsule is imploded as in the conventional approach to inertial fusion to assemble a high-density fuel configuration. Second, a hole is bored through the capsule corona composed of ablated material, as the critical density is pushed close to the high-density core of the capsule by the ponderomotive force associated with high-intensity laser light. Finally, the fuel is ignited by suprathermal electrons, produced in the high-intensity laser-plasma interactions, which then propagate from critical density to this high-density core. This new scheme also drastically reduces the difficulty of the implosion, and thereby allows lower quality fabrication and less stringent beam quality and symmetry requirements from the implosion driver. The difficulty of the fusion scheme is transferred to the technological difficulty of producing the ultrahigh-intensity laser and of transporting this energy to the fuel. C1 LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544. RP TABAK, M (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 33 TC 2282 Z9 2376 U1 26 U2 116 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1626 EP 1634 DI 10.1063/1.870664 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200032 ER PT J AU HAMMEL, BA KILKENNY, JD MUNRO, D REMINGTON, BA KORNBLUM, HN PERRY, TS PHILLION, DW WALLACE, RJ AF HAMMEL, BA KILKENNY, JD MUNRO, D REMINGTON, BA KORNBLUM, HN PERRY, TS PHILLION, DW WALLACE, RJ TI X-RAY RADIOGRAPHIC IMAGING OF HYDRODYNAMIC PHENOMENA IN RADIATION-DRIVEN MATERIALS - SHOCK PROPAGATION, MATERIAL COMPRESSION, AND SHEAR-FLOW SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID LASER; TARGETS AB One- and two-dimensional, time-resolved x-ray radiographic imaging at high photon energy (5-7 keV) is used to study shock propagation, material motion and compression, and the effects of shear flow in solid density samples which are driven by x-ray ablation with the Nova laser. By backlighting the samples with x rays and observing the increase in sample areal density due to shock compression, the trajectories of strong shocks (approximately 40 Mbars) in flight are directly measured in solid density plastic samples. Doping a section of the samples with high-Z material (Br) provides radiographic contrast, allowing a measurement of the shock-induced particle motion. Instability growth due to shear flow at an interface is investigated by imbedding a metal wire in a cylindrical plastic sample and launching a shock in the axial direction. Time-resolved radiographic measurements are made with either a slit-imager coupled to an x-ray streak camera or a pinhole camera coupled to a gated microchannel plate detector, providing approximately 10 mum spatial and approximately 100 ps temporal resolution. RP HAMMEL, BA (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. RI Perry, Theodore/K-3333-2014 OI Perry, Theodore/0000-0002-8832-2033 NR 16 TC 33 Z9 33 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1662 EP 1668 DI 10.1063/1.870668 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200036 ER PT J AU OKUDA, H CHOUEIRI, EY AF OKUDA, H CHOUEIRI, EY TI NUMERICAL-SIMULATION OF NEUTRAL GAS-RELEASE EXPERIMENTS IN THE IONOSPHERE SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID CRITICAL IONIZATION VELOCITY; COLLISIONAL PROCESSES AB A two-and-one-half-dimensional electrostatic particle simulation model has been developed to study neutral gas release experiments into the ionosphere. The electrons are assumed guiding center particles, while the full dynamics of the ions (with real masses) are followed in time and space. Ionization processes of the neutral gas by charge exchange and electron impact are included by means of the Monte Carlo technique. It is shown that the model can be used to simulate the neutral gas interaction, with the ionosphere using realistic experimental parameters. The model was applied to study the critical ionization velocity (CIV) tests recently conducted as part of the ATLAS-1 [Geophys. Res. Lett. 20, 499 (1993)] xenon ps releases from the space shuttle. The simulation results show suprathermal electrons produced by an ion beam-driven lower hybrid instability, create a xenon ion population much more rapidly than the production by classical processes, indicating the prevalence of a CIV-type mechanism. C1 PRINCETON UNIV,ELECT PROPULS & PLASMA DYNAM LAB,PRINCETON,NJ 08544. RP OKUDA, H (reprint author), PRINCETON UNIV,PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 23 TC 9 Z9 9 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1669 EP 1675 DI 10.1063/1.870669 PN 2 PG 7 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200037 ER PT J AU GARY, SP ANDERSON, BJ DENTON, RE FUSELIER, SA MCKEAN, ME AF GARY, SP ANDERSON, BJ DENTON, RE FUSELIER, SA MCKEAN, ME TI A LIMITED CLOSURE RELATION FOR ANISOTROPIC PLASMAS FROM THE EARTHS MAGNETOSHEATH SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID DEPLETION LAYER; MIRROR WAVES; MAGNETOPAUSE; INSTABILITY AB The ions of the terrestrial magnetosheath are typically observed to have bi-Maxwellian velocity distributions with T(perpendicular-to) > T(parallel-to), where perpendicular-to and parallel-to denote directions perpendicular and parallel to the background magnetic field. Observations of the highly compressed magnetosheath have demonstrated an inverse correlation between the proton temperature anisotropy and the proton parallel beta. Hybrid computer simulations have shown that wave-particle scattering by the proton cyclotron anisotropy instability can yield similar correlations between these two parameters. Although these correlations are due to nonlinear plasma processes, they correspond to a threshold of this instability that can be determined from linear Vlasov theory. This proton anisotropy/beta correlation represents a limited closure relation for anisotropic magnetohydrodynamic plasma models. C1 JOHNS HOPKINS UNIV,APPL PHYS LAB,LAUREL,MD 20723. DARTMOUTH COLL,HANOVER,NH 03755. LOCKHEED PALO ALTO RES LABS,PALO ALTO,CA 94304. UNIV CALIF SAN DIEGO,LA JOLLA,CA 92093. RP GARY, SP (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545, USA. RI Anderson, Brian/I-8615-2012 NR 32 TC 46 Z9 46 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1676 EP 1683 DI 10.1063/1.870670 PN 2 PG 8 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200038 ER PT J AU YOUNG, FC HUBBARD, RF LAMPE, M NERI, JM OTTINGER, PF STEPHANAKIS, SJ SLINKER, SP HINSHELWOOD, DD ROSE, DV OLSON, CL WELCH, DR AF YOUNG, FC HUBBARD, RF LAMPE, M NERI, JM OTTINGER, PF STEPHANAKIS, SJ SLINKER, SP HINSHELWOOD, DD ROSE, DV OLSON, CL WELCH, DR TI INTERACTION OF INTENSE MEV LIGHT-ION BEAMS WITH LOW-PRESSURE GASES SO PHYSICS OF PLASMAS LA English DT Article; Proceedings Paper CT 35th Annual Meeting of the Division-of-Plasma-Physics of the American-Physical-Society CY NOV 01-05, 1993 CL ST LOUIS, MO SP AMER PHYS SOC, DIV PLASMA PHYS ID PLASMA AB The interaction of intense proton beams with low-pressure (0.25 to 4 Torr) background gases is studied to evaluate beam-current neutralization during transport. Electrons to neutralize the beam are provided by beam-induced ionization of the gas. In experiments with 1 MeV, 1 kA/cm2 protons, net currents outside the beam envelope and electron densities within the beam envelope are measured for helium, neon, argon, and air. Net-current fractions are 2% to 8% and ionization fractions are 0.6% to 5% for 5 to 7 kA beams. Simulations of the experiments for helium and argon suggest that fast electrons play an important role in generating a significant fraction of the return current in a halo outside the beam. As a result, net currents inside the beam may be larger than inferred from magnetic-field measurements outside the beam. Ions at the head of the beam are observed to lose more energy than expected from collisional energy losses in the background gas. C1 JAYCOR INC,VIENNA,VA 22182. SANDIA NATL LABS,ALBUQUERQUE,NM 87165. MISSION RES CORP,ALBUQUERQUE,NM 87106. RP YOUNG, FC (reprint author), USN,RES LAB,DIV PLASMA PHYS,WASHINGTON,DC 20375, USA. NR 25 TC 16 Z9 16 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1700 EP 1708 DI 10.1063/1.870673 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200041 ER PT J AU EDER, DC AMENDT, P DASILVA, LB LONDON, RA MACGOWAN, BJ MATTHEWS, DL PENETRANTE, BM ROSEN, MD WILKS, SC DONNELLY, TD FALCONE, RW STROBEL, GL AF EDER, DC AMENDT, P DASILVA, LB LONDON, RA MACGOWAN, BJ MATTHEWS, DL PENETRANTE, BM ROSEN, MD WILKS, SC DONNELLY, TD FALCONE, RW STROBEL, GL TI TABLETOP X-RAY LASERS SO PHYSICS OF PLASMAS LA English DT Article ID FIELD-INDUCED IONIZATION; IONIZED PLASMAS; RECOMBINATION AB Details of schemes for two tabletop size x-ray lasers that require a high-intensity short-pulse driving laser are discussed. The first is based on rapid recombination following optical-field ionization. Analytical and numerical calculations of the output properties are presented. Propagation in the confocal geometry is discussed and a solution for x-ray lasing in Li-like N at 247 angstrom is described. Since the calculated gain coefficient depends strongly on the electron temperature, the methods of calculating electron heating following field ionization are discussed. Recent experiments aimed at demonstrating lasing in H-like Li at 135 angstrom are discussed along with modeling results. The second x-ray laser scheme is based on the population inversion obtained during inner-shell photoionization by hard x rays. This approach has significantly higher-energy requirements, but lasing occurs at very short wavelengths (lambda less-than-or-equal-to 15 angstrom). Experiments that are possible with existing lasers are discussed. C1 LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. UNIV CALIF BERKELEY, BERKELEY, CA 94720 USA. UNIV GEORGIA, ATHENS, GA 30602 USA. RP LAWRENCE LIVERMORE NATL LAB, LIVERMORE, CA 94550 USA. NR 38 TC 102 Z9 106 U1 1 U2 3 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 1070-664X EI 1089-7674 J9 PHYS PLASMAS JI Phys. Plasmas PD MAY PY 1994 VL 1 IS 5 BP 1744 EP 1752 DI 10.1063/1.870936 PN 2 PG 9 WC Physics, Fluids & Plasmas SC Physics GA NK072 UT WOS:A1994NK07200047 ER PT J AU LURIE, S LEVIN, A GREVE, LC LABAVITCH, JM AF LURIE, S LEVIN, A GREVE, LC LABAVITCH, JM TI PECTIC POLYMER CHANGES IN NECTARINES DURING NORMAL AND ABNORMAL RIPENING SO PHYTOCHEMISTRY LA English DT Article DE PRUNUS PERSICA; CELL WALL; CONTROLLED ATMOSPHERE; MEALINESS ID CONTROLLED-ATMOSPHERE STORAGE; CELL-WALL CHANGES; WOOLLY BREAKDOWN; MEALY FRUIT; PEACHES; WOOLLINESS AB Nectarines (Prunus persica, cv Fiesta Red) were harvested and either ripened for five days at 20 degrees or stored for eight weeks at 0 degrees in air or in a controlled atmosphere (CA) of 10% CO2 and 15% O-2 before ripening. Air-stored fruit developed the flesh disorder of mealiness, while CA-stored fruit did not. During storage, the degree of esterification of the cell wall decreased in air- but not CA-stored fruits. Air-stored fruits retained more pectin in the sodium carbonate fraction after ripening and the polymers in the trans-1,2-diaminocyclohexane-N,N,N',N'-tetraacetic acid (CDTA) and water-soluble fractions were of smaller M(r) than unstored or CA-stored fruits. Air storage also led to loss of arabinose from the sodium carbonate and guanidine thiocyanate fractions, and a lower arabinose content was also found in the CDTA fraction when air-stored fruits were ripened. The size distribution of components of the pectic fractions from air-stored fruits differed from fruits after harvest or CA-storage. In comparison with air-stored fruit, the CA-stored fruit showed changes in cell wall components which were very similar to those in fruit ripened immediately after harvest. 4 C1 LAWRENCE LIVERMORE NATL LAB,DEPT POMOL,DAVIS,CA 95616. RP LURIE, S (reprint author), AGR RES ORG,VOLCANI CTR,DEPT POSTHARVEST SCI,IL-50250 BET DAGAN,ISRAEL. NR 21 TC 52 Z9 56 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0031-9422 J9 PHYTOCHEMISTRY JI Phytochemistry PD MAY PY 1994 VL 36 IS 1 BP 11 EP 17 DI 10.1016/S0031-9422(00)97003-1 PG 7 WC Biochemistry & Molecular Biology; Plant Sciences SC Biochemistry & Molecular Biology; Plant Sciences GA NL391 UT WOS:A1994NL39100003 ER PT J AU WOLF, S LUCAS, WJ AF WOLF, S LUCAS, WJ TI VIRUS MOVEMENT PROTEINS AND OTHER MOLECULAR PROBES OF PLASMODESMAL FUNCTION SO PLANT CELL AND ENVIRONMENT LA English DT Review DE CARBON ALLOCATION; CELL-TO-CELL COMMUNICATION; DYSFUNCTIONAL MOVEMENT PROTEINS; MACROMOLECULAR TRAFFICKING; PHYSIOLOGICAL DOMAINS; PLASMODESMATA; ROOT-TO-SHOOT RATIOS; TOBACCO MOSAIC VIRUS; TRANSGENIC TOBACCO; VIRAL MOVEMENT PROTEINS; VIRAL RESISTANCE ID TOBACCO MOSAIC-VIRUS; STRANDED NUCLEIC-ACIDS; TRANSGENIC PLANTS; SALICYLIC-ACID; RESISTANCE RESPONSE; ACQUIRED-RESISTANCE; BINDING-PROTEIN; LUCIFER YELLOW; LEAF SYMPLAST; LEAVES AB Plasmodesmata exist as supramolecular complexes that interconnect plant cells to form a symplasmic continuum. Microinjection (dye-coupling) studies confirmed the validity of the symplasmic concept by establishing that molecules of up to 1kDa can pass from cell to cell, via plasmodesmata. Thus, cells can exchange small molecules, such as metabolites and hormones, to coordinate biochemical and physiological processes occurring within tissues. Plasmodesmata also mediate in cell-to-cell transport of macromolecules, including proteins and nucleic acids. This new function was elucidated by studies on virus-plasmodesmata interaction. Plant viruses encode for movement proteins (MPs) that are essential for cell-to-cell spread of infectious material. When expressed in transgenic plants, these MPs are targeted to plasmodesmata and induce a considerable increase in plasmodesmal size exclusion limit (SEL). Studies on mutant MPs confirmed that this increase in SEL is essential for viral infection. Microinjection of MP alone, or together with its conjugate infectious viral transcript, indicated that both the protein and the viral RNA (or DNA) move rapidly from cell to cell. These findings are consistent with the operation of an endogenous plasmodesmal macromolecular transport pathway. Control over this transport pathway has been probed using viral MPs, and the results support the hypothesis that plasmodesmata are involved in the creation of physiological and developmental domains. Elucidation of the molecular constituents involved in the formation and functioning of plasmodesmata will provide valuable insights into the integrated functioning of higher plants, as well as potentiating the development of new strategies for viral resistance. C1 LAWRENCE LIVERMORE NATL LAB,DIV BIOL SCI,PLANT BIOL SECT,DAVIS,CA 95616. RP WOLF, S (reprint author), HEBREW UNIV JERUSALEM,FAC AGR,DEPT FIELD & VEGETABLE CROPS,IL-76100 REHOVOT,ISRAEL. NR 68 TC 20 Z9 20 U1 0 U2 3 PU BLACKWELL SCIENCE LTD PI OXFORD PA OSNEY MEAD, OXFORD, OXON, ENGLAND OX2 0EL SN 0140-7791 J9 PLANT CELL ENVIRON JI Plant Cell Environ. PD MAY PY 1994 VL 17 IS 5 BP 573 EP 585 DI 10.1111/j.1365-3040.1994.tb00150.x PG 13 WC Plant Sciences SC Plant Sciences GA NK352 UT WOS:A1994NK35200007 ER PT J AU KOSOLA, KR BLOOM, AJ AF KOSOLA, KR BLOOM, AJ TI METHYLAMMONIUM AS A TRANSPORT ANALOG FOR AMMONIUM IN TOMATO (LYCOPERSICON-ESCULENTUM L) SO PLANT PHYSIOLOGY LA English DT Article ID ASPERGILLUS-NIDULANS; CHAROPHYTE CELLS; AMINE UNIPORT; PLASMALEMMA; KINETICS; ROOTS; METHYLAMINE; NITRATE; INFLUX; SYSTEM AB Methylammonium (CH3NH3+) has been widely used as an analog of ammonium (NH4+) for examining transport in bacteria and fungi. We compared the kinetics of root CH3NH3+ and NH4+ uptake from solution culture in intact tomato (Lycopersicon esculentum cv T5) plants. Efflux of NH4+ and CH3NH3+ was negligible. The apparent maximum rate of absorption (apparent V-max) was similar for NH4+ and CH3NH3+, but the apparent affinity (apparent K-m) was about 10-fold greater for NH4+ than for CH3NH3+. In characterizing the interaction between NH4+ and CH3NH3+ transport, we used [N-15]-NH4+ and [C-14]CH3NH3+ as well as improved methods for analysis of nonisotopic CH3NH3+ and NH4+. CH3NH3+ acted as an inhibitor of NH4+ influx. Relatively low concentrations of NH4+ strongly inhibited CH3NH3+ influx. Treatments with 1 mM methionine sulfoximine that blocked NH4+ assimilation had little influence on NH4+ inhibition of CH3NH3+ influx. These results suggest that the two ions share a common transport system in tomato, but because this transport system has a much greater affinity for NH4+, CH3NH3+ may be used as a transport analog only when ambient concentrations of NH4+ are very low. C1 LAWRENCE LIVERMORE NATL LAB,DEPT VEGETABLE CROPS,DAVIS,CA 95616. NR 29 TC 29 Z9 30 U1 1 U2 2 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD MAY PY 1994 VL 105 IS 1 BP 435 EP 442 PG 8 WC Plant Sciences SC Plant Sciences GA NL641 UT WOS:A1994NL64100052 ER PT J AU SCHIVELL, J MONTICELLO, DA FISCH, NJ RAX, JM AF SCHIVELL, J MONTICELLO, DA FISCH, NJ RAX, JM TI MODELING OF MEV ALPHA-PARTICLE ENERGY-TRANSFER TO LOWER-HYBRID WAVES SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID CURRENT DRIVE AB The interaction between a lower hybrid wave and a fusion alpha particle displaces the alpha particle simultaneously in space and energy. This results in coupled diffusion. Diffusion of alphas down the density gradient could lead to their transferring energy to the wave. This could, in turn, put energy into current drive. An initial analytic study was done by Fisch and Rax. Here we calculate numerical solutions for the alpha energy transfer and study a range of conditions that are favourable for wave amplification from alpha energy. We find that it is possible for fusion alpha particles to transfer a large fraction of their energy to the lower hybrid wave. The numerical calculation shows that the net energy transfer is not sensitive to the value of the diffusion coefficient over a wide range of practical values. An extension of this idea, the use of a lossy boundary to enhance the energy transfer, is investigated. This technique is shown to offer a large potential benefit. C1 CEA,CTR ETUD SACLAY,F-91191 GIF SUR YVETTE,FRANCE. RP SCHIVELL, J (reprint author), PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. NR 11 TC 2 Z9 2 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD MAY PY 1994 VL 36 IS 5 BP 855 EP 866 DI 10.1088/0741-3335/36/5/007 PG 12 WC Physics, Fluids & Plasmas SC Physics GA NK903 UT WOS:A1994NK90300007 ER PT J AU WONG, KL WILSON, JR CHANG, ZY FU, GY FREDRICKSON, E HAMMETT, GW BUSH, C PHILLIPS, CK SNIPES, J TAYLOR, G AF WONG, KL WILSON, JR CHANG, ZY FU, GY FREDRICKSON, E HAMMETT, GW BUSH, C PHILLIPS, CK SNIPES, J TAYLOR, G TI EXPANSION OF PARAMETER SPACE FOR TOROIDAL ALFVEN EIGENMODE EXPERIMENTS IN TFTR SO PLASMA PHYSICS AND CONTROLLED FUSION LA English DT Article ID ALPHA-PARTICLE LOSSES; FUSION TEST REACTOR; TOKAMAKS; EXCITATION; MODES; WAVES; IONS; INSTABILITIES; SIMULATIONS; PLASMA AB Several techniques were used to excite toroidal Alfven eigenmodes (TAE) in the Tokamak Fusion Test Reactor (TFTR) (Proc. 13th Int. Conf. on Plasma Physics and Controlled Nuclear Fusion Research Vol 1 (Vienna: IAEA, 1990) 9) at magnetic fields above 10 kG. These involved pellet injection to raise the plasma density, variation of the plasma current to change the energetic ion orbit and the q-profile. and ICRF heating to produce energetic hydrogen ions al velocities comparable with 3.5 MeV alpha particles created in deuterium-tritium (d-t) fusion reactions. The amplitude of the TAE modes observed in ICRF-heated plasmas behaves differently from those driven bv neutral beams. This can be explained by the difference in the energetic ion orbits. These experimental results are presented and relevance to fusion reactors are discussed. C1 MIT,CTR PLASMA FUS,CAMBRIDGE,MA 02139. RP WONG, KL (reprint author), PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,POB 451,PRINCETON,NJ 08543, USA. RI Hammett, Gregory/D-1365-2011 OI Hammett, Gregory/0000-0003-1495-6647 NR 29 TC 43 Z9 43 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0741-3335 J9 PLASMA PHYS CONTR F JI Plasma Phys. Control. Fusion PD MAY PY 1994 VL 36 IS 5 BP 879 EP 895 DI 10.1088/0741-3335/36/5/009 PG 17 WC Physics, Fluids & Plasmas SC Physics GA NK903 UT WOS:A1994NK90300009 ER PT J AU Veerasingam, R Campbell, RB Klevans, EH McGrath, RT AF Veerasingam, Ramana Campbell, Robert B. Klevans, Edward H. McGrath, Robert T. TI Ray tracing calculations of ECR absorption in plasma etching and deposition devices SO PLASMA SOURCES SCIENCE & TECHNOLOGY LA English DT Article AB Ray tracing is used to calculate the power absorbed in electron cyclotron resonance plasma sources used in plasma etching and deposition devices. The microwaves are launched at 2.45 GHz corresponding to a fundamental resonance at 875G. The power in each ray is weighted to represent the power distribution of the waveguide mode that is launched into the device. The ray trajectories describe the refraction of the microwave power in the plasma due to the gradients in the plasma density and magnetic field. To calculate power absorption, the damping coefficient is evaluated using a warm plasma correction to the cold plasma dispersion relation. When the rays are launched onto a magnetic beach, most of the microwave power is absorbed before the omega = omega(ce) surface is reached. For the cases studied, the axial width of the absorption layer is typically about 0.5-2 cm and is wider on axis becoming narrower at larger radii. The width of the absorption layer varies inversely with the magnetic field gradient consistent with analytical results obtained from linear theory. The calculations show a significant two-dimensional structure to the absorbed power profile which depends on the launched mode power distribution, the plasma density and the magnetic field profiles. C1 [Campbell, Robert B.; McGrath, Robert T.] Sandia Natl Labs, Albuquerque, NM 87185 USA. [Veerasingam, Ramana; Klevans, Edward H.] Penn State Univ, Dept Nucl Engn, University Pk, PA 16802 USA. RP Veerasingam, R (reprint author), Penn State Univ, Dept Nucl Engn, 231 Sackett Bldg, University Pk, PA 16802 USA. NR 11 TC 7 Z9 7 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0963-0252 J9 PLASMA SOURCES SCI T JI Plasma Sources Sci. Technol. PD MAY PY 1994 VL 3 IS 2 DI 10.1088/0963-0252/3/2/004 PG 12 WC Physics, Fluids & Plasmas SC Physics GA V10QC UT WOS:000207477500004 ER PT J AU PLASYNSKI, SI KLINZING, GE MATHUR, MP AF PLASYNSKI, SI KLINZING, GE MATHUR, MP TI HIGH-PRESSURE VERTICAL PNEUMATIC TRANSPORT INVESTIGATION SO POWDER TECHNOLOGY LA English DT Article ID FLOW AB Vertical pneumatic transport was investigated in a 0.026 m i.d. Lucite tube at various pressures. Nitrogen was the conveying gas at pressures of 101, 790, 2170 and 4238 kPa. Pressure drop, particle velocity, pressure fluctuations and flow patterns were measured or visually observed and recorded. Choking velocity, velocity at minimum pressure drop and the particle friction factor were also investigated at these elevated pressures. Glass beads (97 and 545 mum) and coal (89 and 505 mum) were used as the conveyed solids. The use of Lucite tubing was made possible by encapsulating the entire transport system in a high-pressure containment vessel and pressurizing the outside and the inside of the transport tube simultaneously. A Zenz-type diagram of pressure drop per unit length versus superficial gas velocity was plotted at all pressures investigated. As pressure increased, the curve shifted toward a higher pressure drop at a given gas velocity. Gas velocity at minimum pressure drop thereby decreases as the pressure increases. The same trend is observed for the choking velocity. Average particle velocity of the gas-solid flow mixture approaches the superficial gas velocity at higher pressures more readily than it does at lower pressures. Investigation of the friction factors for the small particles (89 and 97 mum) at elevated pressures revealed that the friction factors due to the gas and solid were dependent on the loading of the system. Expressions were developed for predicting the frictional pressure drop for the gas and solid at low loadings for small particles. Correlations for particle velocity, choking velocity, particle friction factor and velocity at minimum pressure drop are recommended for designing dilute-phase (i.e. epsilon > 0.9) high-pressure transport systems. C1 US DOE,PITTSBURGH ENERGY TECHNOL CTR,PITTSBURGH,PA 15236. RP PLASYNSKI, SI (reprint author), UNIV PITTSBURGH,DEPT CHEM & PETR ENGN,PITTSBURGH,PA 15261, USA. NR 35 TC 23 Z9 26 U1 0 U2 5 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0032-5910 J9 POWDER TECHNOL JI Powder Technol. PD MAY PY 1994 VL 79 IS 2 BP 95 EP 109 DI 10.1016/0032-5910(94)02814-1 PG 15 WC Engineering, Chemical SC Engineering GA NN889 UT WOS:A1994NN88900001 ER PT J AU TRUMBLE, WR HUANG, M WEST, JW REASONER, JL HUANG, JL WANG, CL DOUTHART, RJ BIRDSELL, DC AF TRUMBLE, WR HUANG, M WEST, JW REASONER, JL HUANG, JL WANG, CL DOUTHART, RJ BIRDSELL, DC TI GENE SYNTHESIS AND FUNCTIONAL EXPRESSION OF A PROTEIN EXHIBITING MONODOMAIN IGG FC BINDING SO PROTEIN ENGINEERING LA English DT Article DE FC BINDING PROTEIN; IGG BINDING; PROTEIN ENGINEERING; SINGLE BINDING DOMAIN; SYNTHETIC GENE ID STAPHYLOCOCCUS-AUREUS; ESCHERICHIA-COLI; ALKALINE-PHOSPHATASE; IMMUNOGLOBULIN-G; STREPTOCOCCI; MUTAGENESIS; RECEPTORS; SEQUENCES; PLASMID; REAGENT AB A gene encoding a bacterial IgG Fc binding domain was designed and synthesized. The synthetic DNA fragment was cloned 3' to an inducible trpE promoter such that expression of the gene in Escherichia coli produced abundant Fc binding protein fused to the first seven amino acids of the trpE protein. The recombinant protein contained a single Fc binding domain and demonstrated efficient binding to human IgG in Western blot analysis. This protein degraded rapidly following cell lysis in the absence of protease inhibitors, but could be effectively protected by the addition of protease inhibitor. After purification of the protein by IgG affinity chromatography, IgG Fc binding ability was retained for at least 24 h at either 23 or 37 degrees C and on heating for 15 min at temperatures up to 65 degrees C. No immunoprecipitation was observed in interactions between the monodomain Fc binding protein and IgG molecules. Unlike staphylococcal protein A, no detectable binding of the monodomain IgG Fc binding protein was observed to either IgM or IgA. Truncated proteins, expressed from a series of 3' deletions of the synthetic gene, were used to estimate the minimum portion of a monodomain Fc binding protein that retained Fc binding ability. C1 PACIFIC NW LAB, DEPT BIOL & CHEM, RICHLAND, WA 99352 USA. BIOSYNERGISM INC, SEATTLE, WA 98109 USA. RP TRUMBLE, WR (reprint author), UNIV IDAHO, DEPT BACTERIOL & BIOCHEM, MOSCOW, ID 83844 USA. NR 54 TC 2 Z9 2 U1 0 U2 2 PU OXFORD UNIV PRESS UNITED KINGDOM PI OXFORD PA WALTON ST JOURNALS DEPT, OXFORD, ENGLAND OX2 6DP SN 0269-2139 J9 PROTEIN ENG JI Protein Eng. PD MAY PY 1994 VL 7 IS 5 BP 705 EP 713 DI 10.1093/protein/7.5.705 PG 9 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA NM001 UT WOS:A1994NM00100014 PM 8073040 ER PT J AU SHIN, DH HWANG, KY KIM, KK KIM, SS SWEET, RM SUH, SW AF SHIN, DH HWANG, KY KIM, KK KIM, SS SWEET, RM SUH, SW TI CRYSTALLIZATION AND PRELIMINARY-X-RAY CRYSTALLOGRAPHIC ANALYSIS OF PHOSPHOLIPID TRANSFER PROTEIN FROM MAIZE SEEDLINGS SO PROTEINS-STRUCTURE FUNCTION AND BIOINFORMATICS LA English DT Note DE MAIZE PROTEIN; CRYSTALS; X-RAY DIFFRACTION ID AMINO-ACID-SEQUENCE; ALPHA-AMYLASE INHIBITOR; LIPID TRANSFER PROTEIN; INDIAN FINGER MILLET; INTRACELLULAR EXCHANGE; PURIFICATION; MITOCHONDRIA; BARLEY; SEEDS; LIPOSOMES AB Phospholipid transfer protein from maize seedlings has been crystallized using trisodium citrate as precipitant. The crystal belongs to the orthorhombic space group P2(1)2(1)2(1) with unit cell dimensions of a = 24.46 Angstrom, b = 49.97 Angstrom, and c = 69.99 Angstrom. The presence of one molecule in the asymmetric unit gives a crystal volume per protein mass (V-m) of 2.36 Angstrom(3)/Da and a solvent content of 48% by volume. The X-ray diffraction pattern extends at least to 1.6 Angstrom Bragg spacing when exposed to both CuK alpha and synchrotron X-rays. A set of X-ray data to approximately 1.9 Angstrom Bragg spacing has been collected from a native crystal. (C) 1994 Wiley-Liss, Inc. C1 SEOUL NATL UNIV, COLL NAT SCI, DEPT CHEM, SEOUL 151742, SOUTH KOREA. LUCKY R&D CTR, TAEJON, SOUTH KOREA. BROOKHAVEN NATL LAB, DEPT BIOL, UPTON, NY 11973 USA. RI Suh, Se Won/H-8306-2013 OI Suh, Se Won/0000-0002-1768-4635 NR 31 TC 4 Z9 4 U1 0 U2 1 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0887-3585 J9 PROTEINS JI Proteins PD MAY PY 1994 VL 19 IS 1 BP 80 EP 83 DI 10.1002/prot.340190111 PG 4 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA NJ755 UT WOS:A1994NJ75500010 PM 8066090 ER PT J AU FISHER, CL CABELLI, DE TAINER, JA HALLEWELL, RA GETZOFF, ED AF FISHER, CL CABELLI, DE TAINER, JA HALLEWELL, RA GETZOFF, ED TI THE ROLE OF ARGININE-143 IN THE ELECTROSTATICS AND MECHANISM OF CU,ZN SUPEROXIDE-DISMUTASE - COMPUTATIONAL AND EXPERIMENTAL EVALUATION BY MUTATIONAL ANALYSIS SO PROTEINS-STRUCTURE FUNCTION AND GENETICS LA English DT Article DE BROWNIAN DYNAMICS; MOLECULAR RECOGNITION; SITE-DIRECTED MUTAGENESIS; FACILITATED DIFFUSION ID PULSE-RADIOLYSIS; CHEMICAL MODIFICATION; RECOMBINANT HUMAN; FREE CYSTEINES; ACTIVE-SITE; COPPER; DYNAMICS; MUTANTS; ENZYME; SEQUENCE AB Cu,Zn superoxide dismutase protects cells from oxidative damage by removing superoxide radicals in one of the fastest enzyme reactions known. The redox reaction at the active-site Cu ion is rate-limited by diffusion and enhanced by electrostatic guidance. To quantitatively define the electrostatic and mechanistic contributions of sequence-invariant Arg-143 in human Cu,Zn superoxide dismutase, single-site mutants at this position were investigated experimentally and computationally. Rate constants for several Arg-143 mutants were determined at different pH and ionic strength conditions using pulse radiolytic methods and compared to results from Brownian dynamics simulations. At physioloscal pH, substitution of Arg-143 by Lys caused a a-fold drop in rate, neutral substitutions (Ile, Ala) reduced the rate about 10-fold, while charge-reversing substitutions (Asp, Glu) caused a 100-fold decrease. Position 143 mutants showed pH dependencies not seen in other mutants. At low pH, the acidic residue mutations exhibited protonation/deprotonation effects. At high pH, all enzymes showed typical decreases in rate except the Lys mutant in which the rate dropped off at an unusually low pH. Increasing ionic strength at acidic pH decreased the rates of the wild-type enzyme and Lys mutant, while the rate of the Glu mutant was unaffected. Increasing ionic strength at higher pH (>10) increased the rates of the Lys and Glu mutants while the rate of the wild-type enzyme was unaffected. Reaction simulations with Brownian dynamics incorporating electrostatic effects tested computational predictability of ionic strength dependencies of the wild-type enzyme and the Lys, Ile, and Glu mutants. The calculated and experimental ionic strength profiles gave similar slopes in all but the Glu mutant, indicating that the electrostatic attraction of the substrate is accurately modeled. Differences between the calculated and experimental rates for the Glu and Lys mutants reflect the mechanistic contribution of Arg-143. Results from this joint analysis establish that, aside from the Cu ligands, Arg-143 is the single most important residue in Cu,Zn superoxide dismutase both electrostatically and mechanistically, and provide an explanation for the evolutionary selection of arginine at position 143. (C) 1994 Wiley-Liss, Inc. C1 SCRIPPS RES INST, DEPT MOLEC BIOL MB4, LA JOLLA, CA 92037 USA. BROOKHAVEN NATL LAB, DEPT CHEM, UPTON, NY 11973 USA. UNIV LONDON IMPERIAL COLL SCI & TECHNOL, DEPT BIOCHEM, LONDON SW7 2AZ, ENGLAND. FU NIGMS NIH HHS [GM 11612, GM 37684, GM 39345]; Wellcome Trust NR 41 TC 79 Z9 80 U1 0 U2 8 PU WILEY-LISS PI NEW YORK PA DIV JOHN WILEY & SONS INC 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0887-3585 J9 PROTEINS JI Proteins PD MAY PY 1994 VL 19 IS 1 BP 24 EP 34 DI 10.1002/prot.340190105 PG 11 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA NJ755 UT WOS:A1994NJ75500004 PM 8066083 ER PT J AU ROGERS, RD RIESS, AG AF ROGERS, RD RIESS, AG TI DETECTION AND CLASSIFICATION OF CCD DEFECTS WITH AN ARTIFICIAL NEURAL-NETWORK SO PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC LA English DT Article AB We have developed an artificial neural-network (ANN) system which locates and classifies defects in CCDs. This system, based-on a feedforward neural network, was trained with a conjugate gradient training algorithm using observational data from an astronomical telescope. The network was tested with data from four large CCDs (2048 X 2048 pixels each) and found defects with a higher efficiency and in a much shorter time than human inspectors. This method of detecting and classifying objects in images is quite general and we discuss other applications in astronomy. In an appendix we provide a recipe for neural computing to make this technique more accessible to the astronomical community. C1 HARVARD UNIV,DEPT ASTRON,CAMBRIDGE,MA 02138. RP ROGERS, RD (reprint author), LLNL,INST GEOPHYS & PLANETARY PHYS,L-413,7000 E AVE,LIVERMORE,CA 94550, USA. NR 16 TC 5 Z9 6 U1 0 U2 3 PU ASTRONOMICAL SOC PACIFIC PI SAN FRANCISCO PA 390 ASHTON AVE, SAN FRANCISCO, CA 94112 SN 0004-6280 J9 PUBL ASTRON SOC PAC JI Publ. Astron. Soc. Pac. PD MAY PY 1994 VL 106 IS 699 BP 532 EP 541 DI 10.1086/133409 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA NQ416 UT WOS:A1994NQ41600013 ER PT J AU STURCHIO, NC PIERCE, KL MURRELL, MT SOREY, ML AF STURCHIO, NC PIERCE, KL MURRELL, MT SOREY, ML TI URANIUM-SERIES AGES OF TRAVERTINES AND TIMING OF THE LAST GLACIATION IN THE NORTHERN YELLOWSTONE AREA, WYOMING-MONTANA SO QUATERNARY RESEARCH LA English DT Article ID CLIMATE CHANGE; NATIONAL-PARK; GREENLAND ICE; DEVILS-HOLE; TIME-SCALE; RECORD; STRATIGRAPHY; CHRONOLOGY; ISOTOPES; CALCITE AB Uranium-series age determinations by mass spectrometric methods were done for travertines and associated carbonate veins related to clastic deposits of the last glaciation (Pinedale) in the northern Yellowstone area. Dramatic variations in the hydrologic head are inferred from variations in the elevation of travertine deposition with time and are consistent with the expected hydrologic effects of glaciation. We determine the following chronology of the Pinedale Glaciation, with the key assumption that travertine deposits (and associated carbonate veins) perched high above present thermal springs were deposited when glaciers filled the valley below these perched deposits: (1) the early Pinedale outlet glacier advanced well downvalley between 47,000 and 34,000 yr B.P.; (2) the outlet glacier receded to an interstadial position between 34,000 and 30,000 yr B.P.; (3) an extensive Pinedale ice advance occurred between 30,000 and 22,500 yr B.P.; (4) a major recession occurred between 22,500 and 19,500 yr B.P.; (5) a minor readvance (Deckard Flats) culminated after 19,500 yr B.P.; and (6) recession from the Deckard Flats position was completed before 15,500 yr B.P. This chronology is consistent with the general trend of climatic changes in the northern hemisphere as revealed by recent high-resolution ice-core records from the Greenland ice sheet. (C) 1994 University of Washington. C1 US GEOL SURVEY,DENVER,CO 80225. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. US GEOL SURVEY,MENLO PK,CA 94025. RP STURCHIO, NC (reprint author), ARGONNE NATL LAB,CMT-205,ARGONNE,IL 60439, USA. NR 45 TC 67 Z9 67 U1 0 U2 6 PU ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 SN 0033-5894 J9 QUATERNARY RES JI Quat. Res. PD MAY PY 1994 VL 41 IS 3 BP 265 EP 277 DI 10.1006/qres.1994.1030 PG 13 WC Geography, Physical; Geosciences, Multidisciplinary SC Physical Geography; Geology GA NM451 UT WOS:A1994NM45100002 ER PT J AU SAUER, MC SCHMIDT, KH AF SAUER, MC SCHMIDT, KH TI ELECTRON-CAPTURE RATE CONSTANTS FOR SOLUTES IN ALKANE LIQUIDS MEASURED BY TRANSIENT PHOTOCONDUCTIVITY SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article AB Electron capture rate constants for several solutes in isooctane, cyclohexane and n-hexane are reported. The method of measurement, which allows determination of the rate constants with an accuracy estimated to be better than 5%, involves the use of low power pulses of 337 nm light from a nitrogen laser, and detection of the transient conductivity of escaped electrons. RP SAUER, MC (reprint author), ARGONNE NATL LAB,DIV CHEM,ARGONNE,IL 60439, USA. NR 9 TC 6 Z9 6 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0146-5724 J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD MAY PY 1994 VL 43 IS 5 BP 413 EP 415 DI 10.1016/0969-806X(94)90056-6 PG 3 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA MU841 UT WOS:A1994MU84100001 ER PT J AU STRAUME, T HARRIS, LJ MARCHETTI, AA EGBERT, SD AF STRAUME, T HARRIS, LJ MARCHETTI, AA EGBERT, SD TI NEUTRONS CONFIRMED IN NAGASAKI AND AT THE ARMY PULSED RADIATION FACILITY - IMPLICATIONS FOR HIROSHIMA SO RADIATION RESEARCH LA English DT Article ID EU-152 ACTIVITIES; DOSIMETRY SYSTEM; ATOMIC-BOMB; KERMA; DS86 AB Recent reports have clearly demonstrated that large discrepancies exist between neutron activation measured in Hiroshima and activation calculated using the current dosimetry system, DS86. The reports confirmed previous results for cobalt activation in Hiroshima that suggested problems, and this has spurred a joint U.S.-Japan effort to identify the source(s) of this discrepancy. Here, new results are presented that appear to eliminate both the measurements of neutron activation and the DS86 air-transport calculations as potential sources of the discrepancy in Hiroshima. Computer transport of DS86 fission neutrons through large distances of air was validated using concrete samples from Nagasaki and chloride detectors placed at selected distances from a bare uranium reactor. In both cases, accelerator mass spectrometry was used to measure thermal neutron activation via the reaction, Cl-35(n,gamma)(36)C1 (half-life; 301,000 years). Good agreement was observed between measurements of neutron activation and DS86 calculations for Nagasaki, as well as for the reactor experiment. Thus the large discrepancy observed in Hiroshima appears not to be due to uncertainties in air-transport calculations or in the activation measurements; rather, the discrepancy appears to be due to uncertainties associated with the Hiroshima bomb itself. C1 SCI APPLICAT INT CORP,SAN DIEGO,CA 92121. RP STRAUME, T (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 5507,LIVERMORE,CA 94550, USA. NR 15 TC 28 Z9 28 U1 0 U2 1 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAY PY 1994 VL 138 IS 2 BP 193 EP 200 DI 10.2307/3578589 PG 8 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA NH841 UT WOS:A1994NH84100006 PM 8183989 ER PT J AU CRONKITE, EP INOUE, T BULLIS, JE AF CRONKITE, EP INOUE, T BULLIS, JE TI INFLUENCE OF RADIATION FRACTIONATION ON SURVIVAL OF MICE AND SPLEEN COLONY-FORMING-UNITS SO RADIATION RESEARCH LA English DT Article ID HEMATOPOIETIC STEM-CELLS; FATALLY IRRADIATED MICE; BONE-MARROW; RESIDUAL DAMAGE; SELF-RENEWAL; MOUSE AB C57B1/6 mice were given 10 Gy X rays fractionated in several ways. There was a cyclical pattern of animal survival which was correlated to the fractionation interval and which indicated a periodicity of 6 h. Ten grays given in a single dose is fatal to 100% of the mice and depresses the CFU-S to about one per leg with no evidence of proliferation during the remaining life. Ten grays given in 2.5-Gy increments at 24-h intervals causes no fatalities and results in a similar CFU-S depression but is followed by an exponential increase in CFU-S over the ensuing 12 days. Although bone marrow from survivors of such treatment was comparable to control marrow in its capacity for short-term rescue, it was clearly inferior in its capacity for long-term rescue. The periodicity of 6 h suggests that the cells responsible for survival of the mice have been synchronized into more or less radiosensitive and radioresistant stages of the cell cycle as a result of the time between the 2.5-Gy increments. Implications for the CFU-S and long-term repopulating cells are discussed. C1 YOKOHAMA CITY UNIV,SCH MED,DEPT PATHOL,YOKOHAMA 236,JAPAN. RP CRONKITE, EP (reprint author), BROOKHAVEN NATL LAB,DEPT MED,UPTON,NY 11973, USA. NR 22 TC 4 Z9 4 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAY PY 1994 VL 138 IS 2 BP 266 EP 271 DI 10.2307/3578597 PG 6 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA NH841 UT WOS:A1994NH84100014 PM 8183997 ER PT J AU MORRIS, MD JONES, TD AF MORRIS, MD JONES, TD TI THE RADIOSENSITIVITY OF THE TARGET-CELLS FOR MYELOPOIESIS - COMMENTS ON THE CELL-KINETICS MODEL OF MORRIS ET-AL (RADIAT RES 135, 320-331,1993) - RESPONSE SO RADIATION RESEARCH LA English DT Letter C1 OAK RIDGE NATL LAB,DIV HLTH & SAFETY RES,OAK RIDGE,TN 37831. RP MORRIS, MD (reprint author), OAK RIDGE NATL LAB,DIV ENGN PHYS & MATH,POB 2008,OAK RIDGE,TN 37831, USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD MAY PY 1994 VL 138 IS 2 BP 303 EP 305 DI 10.2307/3578604 PG 3 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA NH841 UT WOS:A1994NH84100021 ER PT J AU KEGELMEYER, WP PRUNEDA, JM BOURLAND, PD HILLIS, A RIGGS, MW NIPPER, ML AF KEGELMEYER, WP PRUNEDA, JM BOURLAND, PD HILLIS, A RIGGS, MW NIPPER, ML TI COMPUTER-AIDED MAMMOGRAPHIC SCREENING FOR SPICULATED LESIONS SO RADIOLOGY LA English DT Article DE BREAST NEOPLASMS, DIAGNOSIS; COMPUTERS, DIAGNOSTIC AID; IMAGES, DIGITIZATION; IMAGES, ENHANCEMENT ID AUTOMATED DETECTION; TUMORS AB PURPOSE: To study the use of a computer vision method as a second reader for the detection of spiculated lesions on screening mammograms. MATERIALS AND METHODS: An algorithmic computer process for the detection of spiculated lesions on digitized screen-film mammograms was applied to 85 four-view clinical cases: 36 cases with cancer proved by means of biopsy and 49 cases with negative findings at examination and follow-up. The computer detections were printed as film with added outlines that indicated the suspected cancers. Four radiologists screened the 85 cases twice, once without and once with the computer reports as ancillary films. RESULTS: The algorithm alone achieved 100% sensitivity, with a specificity of 82%. The computer reports increased the average radiologist sensitivity by 9.7% (P = .005), moving from 80.6% to 90.3%, with no decrease in average specificity. CONCLUSION: The study demonstrated that computer analysis of mammograms can provide a substantial and statistically significant increase in radiologist screening efficacy. C1 SANDIA NATL LABS,LIVERMORE,CA. TEXAS A&M UNIV,HLTH SCI CTR,COLL MED,SCOTT & WHITE CLIN & MEM HOSP,DEPT RADIOL,TEMPLE,TX 76508. TEXAS A&M UNIV,HLTH SCI CTR,COLL MED,SCOTT & WHITE CLIN & MEM HOSP,DEPT BIOSTAT,TEMPLE,TX 76508. TEXAS A&M UNIV,HLTH SCI CTR,COLL MED,SCOTT SHERWOOD & BRINDLEY FDN,TEMPLE,TX. NR 13 TC 228 Z9 229 U1 0 U2 6 PU RADIOLOGICAL SOC NORTH AMER PI EASTON PA 20TH AND NORTHAMPTON STS, EASTON, PA 18042 SN 0033-8419 J9 RADIOLOGY JI Radiology PD MAY PY 1994 VL 191 IS 2 BP 331 EP 337 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA NG955 UT WOS:A1994NG95500010 PM 8153302 ER PT J AU LAMMERT, SA AF LAMMERT, SA TI 1994 DIRECTORY OF MASS-SPECTROMETRY MANUFACTURERS AND SUPPLIERS SO RAPID COMMUNICATIONS IN MASS SPECTROMETRY LA English DT Article ID PRODUCTS; SYSTEMS AB An annual directory of companies which supply mass spectrometers and mass spectrometry components and services. RP LAMMERT, SA (reprint author), OAK RIDGE NATL LAB,M-S 6120,POB 2008,OAK RIDGE,TN 37831, USA. NR 3 TC 7 Z9 7 U1 0 U2 0 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX, ENGLAND PO19 1UD SN 0951-4198 J9 RAPID COMMUN MASS SP JI Rapid Commun. Mass Spectrom. PD MAY PY 1994 VL 8 IS 5 BP 343 EP 357 DI 10.1002/rcm.1290080502 PG 15 WC Chemistry, Analytical; Spectroscopy SC Chemistry; Spectroscopy GA NN136 UT WOS:A1994NN13600001 ER PT J AU VONGOELER, S JONES, S KAITA, R BERNABEI, S DAVIS, W FISHMAN, H GETTELFINGER, G IGNAT, D PAOLETTI, F PETRAVICH, G RIMINI, F RONEY, P STEVENS, J STODIEK, W AF VONGOELER, S JONES, S KAITA, R BERNABEI, S DAVIS, W FISHMAN, H GETTELFINGER, G IGNAT, D PAOLETTI, F PETRAVICH, G RIMINI, F RONEY, P STEVENS, J STODIEK, W TI CAMERA FOR IMAGING HARD X-RAYS FROM SUPRATHERMAL ELECTRONS DURING LOWER-HYBRID CURRENT DRIVE ON PBX-M SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID BREMSSTRAHLUNG EMISSION; TOKAMAK; PLT; STABILITY AB During lower hybrid current drive on tokamaks, suprathermal electrons are generated that emit hard x-ray bremsstrahlung. A pinhole camera has been installed on the PBX-M tokamak that records 128 X 128 pixel images of the hard x-ray plasma bremsstrahlung emitted in the 30-200 keV photon energy range. The camera has a temporal resolution of 3 ms and a spatial resolution of 3-4 cm in the plasma. The detector is a 230-mm-diam hard x-ray image intensifier. This instrument has identified hollow radiation profiles on PBX-M, indicating off-axis current drive. A detailed account of the construction of the hard x-ray camera, its operation, and its performance is given. C1 MIT,CTR PLASMA FUS,CAMBRIDGE,MA 02139. CRIP,BUDAPEST,HUNGARY. JET JOINT UNDERTAKING,ABINGDON OX14 3EA,OXON,ENGLAND. RP VONGOELER, S (reprint author), PRINCETON UNIV,PLASMA PHYS LAB,PRINCETON,NJ 08543, USA. OI Davis, William/0000-0003-0666-7247 NR 24 TC 20 Z9 20 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 1994 VL 65 IS 5 BP 1621 EP 1630 DI 10.1063/1.1144850 PG 10 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA NM231 UT WOS:A1994NM23100025 ER PT J AU RUTKOWSKI, HL EYLON, S CHUPP, WW AF RUTKOWSKI, HL EYLON, S CHUPP, WW TI ION SOURCES FOR INDUCTION LINAC DRIVEN HEAVY-ION FUSION SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB The use of ion sources in induction linacs for heavy ion fusion is fundamentally different from their use in the rf linac-storage rings approach. Induction linacs require very high current, short pulse extraction usually with large apertures which are dictated by the injector design. One is faced with the problem of extracting beams in a pulsed fashion while maintaining high beam quality during the pulse (low emittance). Four types of sources have been studied for this application. The vacuum arc and the rf cusp field source are the plasma-types and the porous plug and hot alumino-silicate surface source are the thermal types. The hot alumino-silicate potassium source has proved to be the best candidate for the next generation of scaled experiments. The porous plug for potassium is somewhat more difficult to use. The vacuum arc suffers from noise and lifetime problems and the rf cusp field source is difficult to use with very short pulses. Operational experience with all of these types of sources is presented. RP RUTKOWSKI, HL (reprint author), LAWRENCE BERKELEY LAB,BERKELEY,CA 94720, USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD MAY PY 1994 VL 65 IS 5 BP 1728 EP 1731 DI 10.1063/1.1144867 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA NM231 UT WOS:A1994NM23100043 ER PT J AU HUSBAND, DM MONDY, LA GANANI, E GRAHAM, AL AF HUSBAND, DM MONDY, LA GANANI, E GRAHAM, AL TI DIRECT MEASUREMENTS OF SHEAR-INDUCED PARTICLE MIGRATION IN SUSPENSIONS OF BIMODAL SPHERES SO RHEOLOGICA ACTA LA English DT Article DE SUSPENSION; PARTICLE MIGRATION; DEMIXING; BIMODAL; ANISOTROPY; CONCENTRATION GRADIENT ID CONCENTRATED SUSPENSIONS; COUETTE-FLOW; SOLID SPHERES; SIMULATION AB A variety of studies reported in the literature have established that initially well mixed suspensions subjected to non-homogeneous shear flows attain an anisotropic particulate structure. It has also been shown that non-homogeneous shearing causes suspensions of unimodal spheres to demix, ie., gradients in solids concentration are formed. The objective of this study was to determine the effect of non-homogeneous shear flows on suspensions of bimodal particles, and specifically, to determine if the solids concentration gradients which develop are accompanied by size segregation of the coarse with respect to the fine fraction. We used the simplest and most direct methods to determine the relative solids concentrations: visual observation of tracer particles in transparent suspensions and physical separation of the coarse and fine solid fractions. Three different types of non-homogeneous shear flows were examined, and in each case the data support two main conclusions: 1) suspended particles migrate from regions of high shear rate to regions of low shear rate, and 2) the coarse fraction of particles migrates much faster than the fine fraction, leading to size segregation of initially well-mixed suspensions. While the former conclusion is consistent with other studies reported in the literature, to our knowledge this paper provides the first data supporting and, to a limited extent, quantifying the latter conclusion. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. RAFAEL,HAIFA,ISRAEL. LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87545. RP HUSBAND, DM (reprint author), WL,MAT DIRECTORATE,MLBP BLDG 654,WRIGHT PATTERSON AFB,OH 45433, USA. NR 19 TC 32 Z9 32 U1 0 U2 3 PU DR DIETRICH STEINKOPFF VERLAG PI BERLIN 33 PA C/O SPRINGER-VERLAG, HEIDELBERGER PLATZ 3, 1000 BERLIN 33, GERMANY SN 0035-4511 J9 RHEOL ACTA JI Rheol. Acta PD MAY-JUN PY 1994 VL 33 IS 3 BP 185 EP 192 DI 10.1007/BF00437303 PG 8 WC Mechanics SC Mechanics GA NX689 UT WOS:A1994NX68900004 ER PT J AU HEISS, W UNTERRAINER, K GORNIK, E HANSEN, WL HALLER, EE AF HEISS, W UNTERRAINER, K GORNIK, E HANSEN, WL HALLER, EE TI INFLUENCE OF IMPURITY ABSORPTION ON GERMANIUM HOT-HOLE LASER SPECTRA SO SEMICONDUCTOR SCIENCE AND TECHNOLOGY LA English DT Article; Proceedings Paper CT 8th International Conference on Hot Carriers in Semiconductors CY AUG 16-20, 1993 CL OXFORD UNIV, OXFORD, ENGLAND SP SCI & ENGN RES COUNCIL, ROYAL SOC, BRIT COUNCIL, OXFORD UNIV HO OXFORD UNIV ID SHALLOW ACCEPTOR STATES; P-TYPE-GE; STIMULATED-EMISSION; EXCITATION-SPECTRA; UNIAXIAL-STRESS; EXCITED-STATES; TRANSITIONS AB We investigate the stimulated emission spectra of p-Ge hot-hole lasers, To clarify the influence of impurity absorption we use for the first time a Tl-doped p-Ge laser. Since we observe a clear difference between the spectrum of this laser and that of normally used Ga-doped lasers with respect to the 'emission gap' and to the low-frequency range, we can give definite evidence that impurity transitions are involved in the lasing process. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP HEISS, W (reprint author), VIENNA TECH UNIV,INST FESTKORPERELEKTRON,A-1040 VIENNA,AUSTRIA. RI Heiss, Wolfgang/F-1200-2011; Unterrainer, Karl/J-4248-2016 OI Heiss, Wolfgang/0000-0003-0430-9550; Unterrainer, Karl/0000-0003-1970-9071 NR 12 TC 15 Z9 15 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0268-1242 J9 SEMICOND SCI TECH JI Semicond. Sci. Technol. PD MAY PY 1994 VL 9 IS 5 SU S BP 638 EP 640 DI 10.1088/0268-1242/9/5S/064 PG 3 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Materials Science; Physics GA NM753 UT WOS:A1994NM75300064 ER PT J AU BROWN, PN SAAD, Y AF BROWN, PN SAAD, Y TI CONVERGENCE THEORY OF NONLINEAR NEWTON-KRYLOV ALGORITHMS SO SIAM JOURNAL ON OPTIMIZATION LA English DT Article DE NONLINEAR SYSTEMS; NONLINEAR PROJECTION METHODS; KRYLOV SUBSPACE METHODS; INEXACT NEWTON METHODS; TRUST REGION TECHNIQUES; CONJUGATE GRADIENT METHODS ID CONJUGATE-GRADIENT METHOD; LINEAR-SYSTEMS; MINIMIZATION; EQUATIONS; GMRES; CODES AB This paper presents some convergence theory for nonlinear Krylov subspace methods. The basic idea of these methods, which have been described by the authors in an earlier paper, is to use variants of Newton's iteration in conjunction with a Krylov subspace method for solving the Jacobian linear systems. These methods are variants of inexact Newton methods where the approximate Newton direction is taken from a subspace of small dimension. The main focus of this paper is to analyze these methods when they are combined with global strategies such as linesearch techniques and model trust region algorithms. Most of the convergence results are formulated for projection onto general subspaces rather than just Krylov subspaces. C1 UNIV MINNESOTA,DEPT COMP SCI,MINNEAPOLIS,MN 55455. RP BROWN, PN (reprint author), LAWRENCE LIVERMORE NATL LAB,DIV COMP & MATH RES,APPL MATH SCI RES PROGRAM,L-316,LIVERMORE,CA 94550, USA. NR 32 TC 115 Z9 122 U1 2 U2 8 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 SN 1052-6234 J9 SIAM J OPTIMIZ JI SIAM J. Optim. PD MAY PY 1994 VL 4 IS 2 BP 297 EP 330 DI 10.1137/0804017 PG 34 WC Mathematics, Applied SC Mathematics GA PW285 UT WOS:A1994PW28500005 ER PT J AU BRAMBLE, JH GOLDSTEIN, CI PASCIAK, JE AF BRAMBLE, JH GOLDSTEIN, CI PASCIAK, JE TI ANALYSIS OF V-CYCLE MULTIGRID ALGORITHMS FOR FORMS DEFINED BY NUMERICAL QUADRATURE SO SIAM JOURNAL ON SCIENTIFIC COMPUTING LA English DT Article; Proceedings Paper CT 1992 Copper Mountain Conference on Iterative Methods in Numerical Linear Algebra CY APR 09-14, 1992 CL COPPER MT RESORT, COPPER MT, CO SP US DOE HO COPPER MT RESORT DE MULTIGRID METHODS; ELLIPTIC EQUATIONS; FINITE ELEMENTS; NUMERICAL QUADRATURE AB The authors describe and analyze certain V-cycle multigird algorithms with forms defined by numerical quadrature applied to the approximation of symmetric second-order elliptic boundary value problems. This approach can be used for the efficient solution of finite element systems resulting from numerical quadrature as well as systems arising from finite difference discretizations. The results are based on a regularity free theory and hence apply to meshes with local grid refinement as well as the quasi-uniform case. It is shown that uniform (independent of the number of levels) convergence rates often hold for appropriately defined V-cycle algorithms with as few as one smoothing per grid. These results bold even on applications without full elliptic regularity, e.g., a domain in R2 with a crack. C1 BROOKHAVEN NATL LAB,DEPT APPL MATH,UPTON,NY 11973. RP BRAMBLE, JH (reprint author), CORNELL UNIV,DEPT MATH,ITHACA,NY 14853, USA. NR 17 TC 4 Z9 5 U1 0 U2 0 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 SN 1064-8275 J9 SIAM J SCI COMPUT JI SIAM J. Sci. Comput. PD MAY PY 1994 VL 15 IS 3 BP 566 EP 576 DI 10.1137/0915037 PG 11 WC Mathematics, Applied SC Mathematics GA NH805 UT WOS:A1994NH80500006 ER PT J AU CARY, JW SIMMONS, CS MCBRIDE, JF AF CARY, JW SIMMONS, CS MCBRIDE, JF TI INFILTRATION AND REDISTRIBUTION OF ORGANIC LIQUIDS IN LAYERED POROUS-MEDIA SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID WATER; PERMEABILITY; AIR AB The remediation of many toxic waste sites throughout the world requires a better understanding of the flow of organic liquids in the vadose zone. The infiltration and redistribution of three water-immiscible oils into columns filled with porous material containing different textural layers are reported. In some experiments, oil followed water into the columns and in others, water followed oil. An explicit, one-dimensional, multiphase flow code was used to model the results. The numerical model contains elements of code that: (i) mimic the Haines jump phenomenon in dry sand, (ii) account for oil entrapment when water infiltrates, (iii) include forces on the oil phase caused by surface-spreading pressures at the oil front in water-wetted pores, (iv) include forces on the oil phase caused by water intrusion into hydrophilic oil-saturated pores, and (v) generate a factor that matches the water potentials of textural layers for the initial boundary conditions. In general, the model did a reasonable job of predicting the distribution of both water and oil 8 h after infiltration was started, though some unresolved problems persist. The liquid potential matching factor and the hydrophobicity of the mineral particles induced by a transmission oil have practical applications. The matching factor may be easily adapted to all codes that model flow through layers. The in situ creation of hydrophobic mineral particles may prove useful for containing immiscible organic liquids that leak into the vadose zone. RP CARY, JW (reprint author), PACIFIC NW LAB, POB 999,BATTELLE BLVD, RICHLAND, WA 99352 USA. NR 15 TC 6 Z9 6 U1 0 U2 2 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD MAY-JUN PY 1994 VL 58 IS 3 BP 704 EP 711 PG 8 WC Soil Science SC Agriculture GA NX647 UT WOS:A1994NX64700010 ER PT J AU ZACHARA, JM SMITH, SC AF ZACHARA, JM SMITH, SC TI EDGE COMPLEXATION REACTIONS OF CADMIUM ON SPECIMEN AND SOIL-DERIVED SMECTITE SO SOIL SCIENCE SOCIETY OF AMERICA JOURNAL LA English DT Article ID MAGNESIUM EXCHANGE; WYOMING BENTONITE; WATER INTERFACE; ADSORPTION; MONTMORILLONITE; SURFACE; KAOLINITE; CALCIUM; SODIUM AB The contribution of edge-complexation reactions to metal ion sorption by smectites has not been well documented through experimentation or modeling. A model containing fixed-charge (X -) and hydroxylated edge sites (AlOH and SiOH) was applied to sorption data for Cd on SWy-1 smectite and a smectitic soil isolate in Na+, Ca2+, and mixed electrolytes to evaluate the potential contributions of ion exchange and surface coordination to metal cation binding. Sorption modeling was performed with FITEQL. Edge reactions were described using the triple-layer model (TLM) and an inner sphere Cd complex on AlOH sites and outer sphere complexes on SiOH sites. The complexation reactions were parameterized using (i) Cd sorption data from silica and alumina and (ii) site concentration estimates based on cation-exchange capacity (X-) and particle size measurements (AlOH and SiOH). Ion-exchange reactions were described in half-reaction format; exchange constants were fit using Cd sorption data in either Na+ or Ca2+ electrolyte. The sorption data was qualitatively described across ranges in pH and electrolyte concentration using a combination of ion exchange (CdX2) and edge (AlOCd+) complexes. Complexation of Cd to edge SiOH was calculated to be unimportant. The calculated contribution of AlOCd+ complexes increased with increases in pH and ionic strength. Good predictions of Cd sorption in mixed electrolytes were obtained using constants derived from single-electrolyte systems. Edge sorption reactions were computed to be more important for the soil smectite than for SWy-1 because of its smaller particle size. However, the slope and magnitude of sorption on the soil isolate was inadequately described by the model. Competitive sorption reactions on the edge sites and binding to organic material are additional factors that must be considered to adequately describe Cd sorption to smectitic soil clays. RP ZACHARA, JM (reprint author), PACIFIC NW LAB, DEPT GEOSCI, POB 999,BATTELLE BLVD, RICHLAND, WA 99352 USA. NR 31 TC 58 Z9 58 U1 2 U2 9 PU SOIL SCI SOC AMER PI MADISON PA 677 SOUTH SEGOE ROAD, MADISON, WI 53711 SN 0361-5995 J9 SOIL SCI SOC AM J JI Soil Sci. Soc. Am. J. PD MAY-JUN PY 1994 VL 58 IS 3 BP 762 EP 769 PG 8 WC Soil Science SC Agriculture GA NX647 UT WOS:A1994NX64700018 ER PT J AU PESARAN, AA WIPKE, KB AF PESARAN, AA WIPKE, KB TI USE OF UNGLAZED TRANSPIRED SOLAR COLLECTORS FOR DESICCANT COOLING SO SOLAR ENERGY LA English DT Article AB The use of unglazed transpired solar collectors for desiccant regeneration in a solid desiccant cooling cycle was investigated because these collectors are less expensive than conventional glazed flat-plate collectors. Using computer models, we studied the performance of a desiccant cooling ventilation cycle integrated with either unglazed transpired collectors or conventional glazed flat-plate collectors. We found that the thermal coefficient of performance of the cooling system with unglazed collectors was lower than that of the cooling system with glazed collectors because the former system did not use the heat of adsorption released during the dehumidification process. Although the area required for the unglazed collector array was 70% more than that required for the glazed collector array in a 10.56 kW (3 ton) solar cooling system, the cost of the unglazed array was 45% less than the cost of the glazed array. The simple payback period of the unglazed collector was half of the payback period of the glazed collector when replacing an equivalent gas-fired air heater. Although the use of unglazed transpired collectors seems to make economic sense relative to use of glazed conventional collectors, some practical considerations may limit their use for desiccant regeneration. RP PESARAN, AA (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO, USA. NR 13 TC 15 Z9 15 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-092X J9 SOL ENERGY JI Sol. Energy PD MAY PY 1994 VL 52 IS 5 BP 419 EP 427 DI 10.1016/0038-092X(94)90119-M PG 9 WC Energy & Fuels SC Energy & Fuels GA NG537 UT WOS:A1994NG53700007 ER PT J AU LAMPERT, CM VISCO, SJ DOEFF, MM MA, YP HE, Y GIRON, JC AF LAMPERT, CM VISCO, SJ DOEFF, MM MA, YP HE, Y GIRON, JC TI CHARACTERISTICS OF LAMINATED ELECTROCHROMIC DEVICES USING POLYORGANODISULFIDE ELECTRODES SO SOLAR ENERGY MATERIALS AND SOLAR CELLS LA English DT Article ID REDOX POLYMERIZATION ELECTRODES; ALL-SOLID-STATE; ELECTROCHEMICAL PROPERTIES; BATTERIES AB The application of polyorganodisulfides as optically passive counter-electrodes in a variety of electrochromic smart glazing devices are discussed. Characteristic data is presented for electrochromic devices using proton, and lithium coloration ions with modified polyethylene oxide electrolyte and polydimercaptothiadiazole positive electrodes. Solid state devices, consisting of molybdenum doped WO3, amorphous polyethylene oxide electrolyte (a-PEO), and a polyorganodisulfide counter-electrode colored rapidly from a pale yellow to a deep blue-green, upon application of -1.2 V DC. The photopic transmittance (T(p)) changes from 61 to 9%, and the solar transmittance (T(s)) changes from 45 to 5% during the coloration process. Also, our experiments with polyimidazole are detailed. This family of compounds due to its unique electrical and ion conduction properties allow a single composite ion storage and ion conductor electrode to be made, simplifying the device construction. Devices made from this family of compounds color to deep blue-gray upon application of -1.2-1.5 V DC. Bleaching occurs at -0.4 to -0.5 V DC. The photopic transmittance changed from 55 to 9%, and the solar transmittance from 34 to 4% during coloration. Both coloration and bleaching are quite rapid. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP LAMPERT, CM (reprint author), LAWRENCE BERKELEY LAB,DIV ENERGY & ENVIRONM,1 CYCLOTRON RD,BERKELEY,CA 94720, USA. RI Doeff, Marca/G-6722-2013 OI Doeff, Marca/0000-0002-2148-8047 NR 12 TC 9 Z9 12 U1 1 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0248 J9 SOL ENERG MAT SOL C JI Sol. Energy Mater. Sol. Cells PD MAY PY 1994 VL 33 IS 1 BP 91 EP 105 DI 10.1016/0927-0248(94)90293-3 PG 15 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA NU470 UT WOS:A1994NU47000011 ER PT J AU CHEN, XM QUINN, JJ AF CHEN, XM QUINN, JJ TI ON THE INTERPRETATION OF THE PHOTOLUMINESCENCE SPECTRUM OF FRACTIONAL QUANTUM HALL SYSTEMS SO SOLID STATE COMMUNICATIONS LA English DT Article ID HIERARCHY; INTEGER; STATES; LIQUID; FLUID AB The photoluminescence of a fractional quantum Hall system is studied by numerically diagonalizing the Hamiltonian of an electron-hole system of a finite-size. When valence band holes are located at a distance d away from the electron layer, the PL spectrum in general displays a multipeak structure that can be classified in terms of the number of quasielectrons involved in the recombination process. The 3-quasielectron process, which for large d is suppressed by the repulsive interaction between quasielectrons, is greatly enhanced by the attractive interaction between quasielectrons and the valence band hole when d is of the order of or smaller than the magnetic length l. The existence of the bound state complex (consisting of two quasielectrons and one hole) predicted earlier at d approximately 1.5l can also be traced in the luminescence spectrum. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP CHEN, XM (reprint author), UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996, USA. NR 17 TC 1 Z9 1 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD MAY PY 1994 VL 90 IS 5 BP 303 EP 306 DI 10.1016/0038-1098(94)90156-2 PG 4 WC Physics, Condensed Matter SC Physics GA NH618 UT WOS:A1994NH61800005 ER PT J AU CHOI, IH YU, PY AF CHOI, IH YU, PY TI PRESSURE-DEPENDENCE OF RAMAN-SCATTERING IN AGGASE2 SO SOLID STATE COMMUNICATIONS LA English DT Article AB The pressure dependence of several one-phonon Raman modes in AgGaSe2 has been measured by using a dye laser tuned near the bandgap exciton at low temperatures to enhance their Raman intensities. Most of the modes exhibit large nonlinear pressure dependence. Although none of the observed modes showed any softening at pressures approaching the structural phase transition value, the GAMMA5L(W3) mode at 139 cm-1 was found to broaden anomalously with pressure. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. CHUNG AN UNIV,DEPT PHYS,SEOUL,SOUTH KOREA. RP CHOI, IH (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. NR 10 TC 4 Z9 4 U1 1 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD MAY PY 1994 VL 90 IS 6 BP 345 EP 348 DI 10.1016/0038-1098(94)90795-1 PG 4 WC Physics, Condensed Matter SC Physics GA NK057 UT WOS:A1994NK05700001 ER PT J AU FUHRER, MS HOU, JG XIANG, XD ZETTL, A AF FUHRER, MS HOU, JG XIANG, XD ZETTL, A TI C60 INTERCALATED GRAPHITE - PREDICTIONS AND EXPERIMENTS SO SOLID STATE COMMUNICATIONS LA English DT Article ID SUPERCONDUCTIVITY AB We propose a new class of Graphite Intercalation Compounds (GICs) containing C60 and alkali metals. The compound C32K4C60 is predicted and attempts to synthesize it using a C8K precursor and benzene-dissolved C60 are reported. C8K samples exposed to C60 and benzene display a reproducible resistive transition at 19.5K indicative of superconductivity. C8K samples exposed to benzene alone show no transition for T > 4.2K. Possible origins of the superconductivity are discussed. C1 LAWRENCE BERKELEY LAB,DIV MAT SCI,BERKELEY,CA 94720. RP FUHRER, MS (reprint author), UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720, USA. RI Fuhrer, Michael/E-7634-2010; Hou, Jianguo/G-5076-2010; Xiang, Xiaodong/A-9445-2012; Zettl, Alex/O-4925-2016 OI Fuhrer, Michael/0000-0001-6183-2773; Zettl, Alex/0000-0001-6330-136X NR 16 TC 14 Z9 14 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD MAY PY 1994 VL 90 IS 6 BP 357 EP 360 DI 10.1016/0038-1098(94)90798-6 PG 4 WC Physics, Condensed Matter SC Physics GA NK057 UT WOS:A1994NK05700004 ER PT J AU WANG, ZN SHI, DL AF WANG, ZN SHI, DL TI SELF-ORGANIZED CRITICALITY NEAR THE BEAN CRITICAL-STATE - A POWER-LAW BEHAVIOR OF FLUX MOTION SO SOLID STATE COMMUNICATIONS LA English DT Article ID 1-F NOISE; FLUCTUATIONS AB The characteristics of the self-organized criticality (SOC) theory have been investigated in high-T(c) superconductors (single crystals of Bi2SrCa2Cu2Ox and YBa2Cu3Ox) near the Bean critical state. Using the SOC framework, we develop a power-law relation 1 - j/j(c) = (t/psitau)psi that describes the dynamical behavior of the vortex state. We experimentally show that the vortex state is a temporally and spatially extended SOC system. C1 IIT,DEPT PHYS,CHICAGO,IL 60616. RP WANG, ZN (reprint author), ARGONNE NATL LAB,DIV MAT SCI,ARGONNE,IL 60439, USA. NR 18 TC 7 Z9 7 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0038-1098 J9 SOLID STATE COMMUN JI Solid State Commun. PD MAY PY 1994 VL 90 IS 6 BP 405 EP 408 DI 10.1016/0038-1098(94)90809-5 PG 4 WC Physics, Condensed Matter SC Physics GA NK057 UT WOS:A1994NK05700015 ER PT J AU BATES, JB GRUZALSKI, GR DUDNEY, NJ LUCK, CF YU, XH AF BATES, JB GRUZALSKI, GR DUDNEY, NJ LUCK, CF YU, XH TI RECHARGEABLE THIN-FILM LITHIUM BATTERIES SO SOLID STATE IONICS LA English DT Article; Proceedings Paper CT 9th International Conference on Solid State Ionics CY SEP 12-17, 1993 CL THE HAGUE, NETHERLANDS SP DELFT UNIV TECHNOL, UNIV TWENTE, MINIST ECON AFFAIRS (NETHERLANDS), ROYAL NETHERLANDS CHEM SOC, INT SCI FDN, NEW YORK, ELECTROCHEM SOC INC, HIGH TEMP MAT DIV, NETHERLANDS AGCY ENERGY & ENVIRONM, NETHERLANDS ENERGY RES FDN, ELSEVIER SCI PUBL B V, TNO, DSM, BURGOMASTER & ALDERMAN THE HAGUE, INT SOC SOLID STATE ION ID AMORPHOUS V2O5; MICROBATTERIES; CONDUCTIVITY; ELECTROLYTE; GLASSES AB Rechargeable thin-film batteries consisting of lithium metal anodes, an amorphous inorganic electrolyte, and cathodes of lithium intercalation compounds have been fabricated and characterized. These include Li-TiS2, Li-V2O5, and Li-LiMn2O4 cells with open circuit voltages at full charge of about 2.5 V, 3.7 V, and 4.2 V, respectively. The realization of these robust cells, which can be cycled thousands of times, was possible because of the stability of the amorphous lithium electrolyte, lithium phosphorus oxynitride. This material has a typical composition of Li3.3PO3.8N0.22 and a conductivity at 25-degrees-C of 2 muS/cm. The thin-film cells have been cycled at 100% depth of discharge using current densities of 5 to 100 muA/cm2. Over most of the charge-discharge range, the internal resistance appears to be dominated by the cathode, and the major source of the resistance is the diffusion of Li+ ions from the electrolyte into the cathode. Chemical diffusion coefficients were determined from ac impedance measurements. RP BATES, JB (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. RI Dudney, Nancy/I-6361-2016 OI Dudney, Nancy/0000-0001-7729-6178 NR 24 TC 158 Z9 160 U1 7 U2 76 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-2738 J9 SOLID STATE IONICS JI Solid State Ion. PD MAY-JUN PY 1994 VL 70 BP 619 EP 628 DI 10.1016/0167-2738(94)90383-2 PN 1 PG 10 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA NY911 UT WOS:A1994NY91100104 ER PT J AU LUDWIG, F DANTSKER, E NEMETH, DT KOELLE, D MIKLICH, AH CLARKE, J KNAPPE, S KOCH, H THOMSON, R AF LUDWIG, F DANTSKER, E NEMETH, DT KOELLE, D MIKLICH, AH CLARKE, J KNAPPE, S KOCH, H THOMSON, R TI FABRICATION ISSUES IN OPTIMIZING YBA2CU3O7-X FLUX TRANSFORMERS FOR LOW 1/F NOISE SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID MAGNETOMETER AB We describe an improved interconnect technology for the fabrication of multiturn flux transformers from YBa2Cu3O7-x-SrTiO3-YBa2Cu3O7-x multilayers. The essential improvements are reductions in the thicknesses of the trilayer films, typically to 100 nm, 250 nm and 250 nm respectively, and in the deposition rate, to 0.07 nm/laser pulse. This process yields crossovers in which the critical current density in the upper YBa2Cu3O7-x film at 77 K is (2-3) X 10(6) cm-2. In situ trilayers exhibited 1/f flux noise levels at 1 Hz below the measurement sensitivity of 15 muPHI0 Hz-1/2, where PHI0 is the flux quantum. However the flux noise of trilayers in which each layer had been patterned was significantly higher. The best flip-chip magnetometer had a white noise of 40 fT Hz-1/2, increasing to 340 fT Hz-1/2 at 1 Hz; the corresponding flux noise levels were 9 muPHI0 Hz-1/2 and 75 muPHI0 Hz-1/2. C1 LAWRENCE BERKELEY LAB, DIV MAT SCI, BERKELEY, CA 94720 USA. PHYS TECH BUNDESANSTALT, INST BERLIN, D-10587 BERLIN, GERMANY. NATL INST STAND & TECHNOL, BOULDER, CO 80303 USA. RP UNIV CALIF BERKELEY, DEPT PHYS, BERKELEY, CA 94720 USA. RI Koelle, Dieter/E-5111-2011 NR 13 TC 17 Z9 17 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 EI 1361-6668 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD MAY PY 1994 VL 7 IS 5 BP 273 EP 276 DI 10.1088/0953-2048/7/5/011 PG 4 WC Physics, Applied; Physics, Condensed Matter SC Physics GA NM578 UT WOS:A1994NM57800012 ER PT J AU RAO, GR MONAR, K LEE, EH TREGLIO, JR AF RAO, GR MONAR, K LEE, EH TREGLIO, JR TI METAL-ION IMPLANTATION EFFECTS ON SURFACE-PROPERTIES OF POLYMERS SO SURFACE & COATINGS TECHNOLOGY LA English DT Article ID WEAR PROPERTIES; HARDNESS; INDENTATION; POLYIMIDE; LOAD AB Polyethylene (PE), polycarbonate (PC) and polyetherimide (PEI) have been implanted with a variety of metallic ions from a metal vapor arc source at low energies yielding shallow depth implants. PC and PEI have been implanted with Cr, Ti, Si and Pt, while PE was implanted with Cr and Ti. Nanoindentation hardness and surface resistivity changes were measured for the implanted polymers. Results showed that the Ti and Si implantations caused similar hardness increases for PC and PEI while Cr implantation resulted in the largest hardness improvement for the two polymers. These effects were attributed to energy and dose effects. Pt implantation, on the contrary, had very little effect on hardness. This was attributed to a greater extent of chain scission caused by nuclear collisions by the heavy Pt ions than cross-linking caused by electronic excitation. In the case of PE, Ti and Cr yielded similar hardness increases although the measured hardness values were smaller than those for PC and PEI. The implantations also decreased electrical resistivities of the polymers. Ti, Si and Cr implantations exhibited trends for a decrease in resistivity similar to those for the increase in hardness suggesting similar underlying causes, namely cross-linking. It appears that irradiation-induced cross-links provide paths for increased mobility of carriers contributing towards decreased resistivity. Pt implantation yielded the largest increase in conductivity as a result of the high dose used as well as the deposition of microdroplets of Pt which form at the metal ion source causing Pt to accumulate at the polymer surface leading to metallic conduction. This study represents the first use of a mixed energy spectrum of ion implantation to modify surface properties of polymers. C1 ISM TECHNOL INC,SAN DIEGO,CA 92131. UNIV TENNESSEE,DEPT MAT SCI & ENGN,KNOXVILLE,TN 37996. RP RAO, GR (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,POB 2008,OAK RIDGE,TN 37831, USA. NR 17 TC 42 Z9 48 U1 0 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0257-8972 J9 SURF COAT TECH JI Surf. Coat. Technol. PD MAY PY 1994 VL 64 IS 2 BP 69 EP 74 PG 6 WC Materials Science, Coatings & Films; Physics, Applied SC Materials Science; Physics GA NN237 UT WOS:A1994NN23700002 ER PT J AU RAEKER, TJ DEPRISTO, AE AF RAEKER, TJ DEPRISTO, AE TI THE DEFINITION AND CALCULATION OF INTERFACIAL ENERGIES FOR THIN-FILMS SO SURFACE SCIENCE LA English DT Article ID CORRECTED EFFECTIVE-MEDIUM; MOLECULAR-DYNAMICS SIMULATION; GROWTH; DEPOSITION; RELAXATION; EPITAXY; AG(100); SYSTEMS; METALS; NI AB We provide a new definition of the interfacial energy which eliminates three physically extraneous contributions from the conventional definition: (1) the strain or stress energy due to lattice mismatch between film and substrate; (2) the surface energy of the film-vacuum interface; and, (3) the substrate surface energy contribution from substrate layers below the film layers. This new interface energy then quantifies the variation in interactions among film/substrate, film/film and substrate/substrate bonding. Using this new definition, we derive the equations for evaluation of the interfacial energy in terms of the interaction energy for any atom in each layer of the film/substrate, film/film and substrate/substrate systems. With this formulation, it is simple to determine the dependence of the interfacial energy on the film thickness using virtually any interaction potential. Using a corrected effective medium theory, we present results for a few pseudomorphic film systems containing Ni/Cu, Ni/Ag, Cu/Ag and Rh/Ag on (111) and (100) surfaces. These systems cover a wide range of lattice mismatch and alloy formation energies. The results demonstrate that the new definition of interfacial energy converges after only 3-4 film layers, regardless of the degree of lattice mismatch. We also show that the interfacial energies at (100) and (111) interfaces differ and that the interfacial energy for a given pair of materials depends on which of the materials is the film. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. NR 37 TC 6 Z9 6 U1 3 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 1 PY 1994 VL 310 IS 1-3 BP 337 EP 346 DI 10.1016/0039-6028(94)91397-8 PG 10 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA NK049 UT WOS:A1994NK04900044 ER PT J AU KELCHNER, CL HALSTEAD, DM PERKINS, LS WALLACE, NM DEPRISTO, AE AF KELCHNER, CL HALSTEAD, DM PERKINS, LS WALLACE, NM DEPRISTO, AE TI CONSTRUCTION AND EVALUATION OF EMBEDDING FUNCTIONS SO SURFACE SCIENCE LA English DT Article ID CORRECTED EFFECTIVE-MEDIUM; ATOM-METHOD; MOLECULAR-DYNAMICS; TRANSITION-METALS; BODY POTENTIALS; SELF-DIFFUSION; SURFACES; CU; CLUSTERS; AG AB Non-self-consistent density functional theories require specification of the embedding energy for an atom in a reference system. We combine the embedding energies determined from linear muffin tin orbital (LMTO) calculations of the bulk cohesive energy curves with those determined from the experimental diatomic binding curve. These new embedding functions contain information about the variation of binding with both coordination and separation between atomic centers. These are shown to be superior to embedding functions determined solely from bulk cohesive energy curves through tests on structures and energies of small metal clusters, self-diffusion of adatoms on metal surfaces, and scattering of metal atoms from metal surfaces. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. RP KELCHNER, CL (reprint author), IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011, USA. NR 43 TC 124 Z9 124 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAY 1 PY 1994 VL 310 IS 1-3 BP 425 EP 435 DI 10.1016/0039-6028(94)91405-2 PG 11 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA NK049 UT WOS:A1994NK04900052 ER PT J AU STORMS, E AF STORMS, E TI WARMING UP TO COLD-FUSION SO TECHNOLOGY REVIEW LA English DT Article RP STORMS, E (reprint author), LOS ALAMOS NATL LAB,LOS ALAMOS,NM 87544, USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MASS INST TECHNOL PI CAMBRIDGE PA CAMBRIDGE, MA 02139 SN 0040-1692 J9 TECHNOL REV JI Technol. Rev. PD MAY-JUN PY 1994 VL 97 IS 4 BP 19 EP 29 PG 11 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA NH366 UT WOS:A1994NH36600020 ER PT J AU GILBERT, RO DOCTOR, PG AF GILBERT, RO DOCTOR, PG TI THE USE OF CONDITIONAL SIMULATION IN NUCLEAR-WASTE-SITE PERFORMANCE ASSESSMENT - DISCUSSION SO TECHNOMETRICS LA English DT Discussion ID NUREG-1150 C1 PACIFIC NW LAB, CTR EARTH & ENVIRONM SCI, RICHLAND, WA 99352 USA. RP GILBERT, RO (reprint author), PACIFIC NW LAB, DEPT ANALYT SCI, STAT DESIGN & ANAL GRP, RICHLAND, WA 99352 USA. NR 16 TC 0 Z9 0 U1 0 U2 0 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD MAY PY 1994 VL 36 IS 2 BP 141 EP 144 PG 4 WC Statistics & Probability SC Mathematics GA NH522 UT WOS:A1994NH52200002 ER PT J AU WENDELBERGER, J BECKMAN, R AF WENDELBERGER, J BECKMAN, R TI THE USE OF CONDITIONAL SIMULATION IN NUCLEAR-WASTE-SITE PERFORMANCE ASSESSMENT - DISCUSSION SO TECHNOMETRICS LA English DT Discussion RP WENDELBERGER, J (reprint author), LOS ALAMOS NATL LAB,STAT GRP,LOS ALAMOS,NM 87545, USA. NR 2 TC 0 Z9 0 U1 0 U2 1 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD MAY PY 1994 VL 36 IS 2 BP 144 EP 147 PG 4 WC Statistics & Probability SC Mathematics GA NH522 UT WOS:A1994NH52200003 ER PT J AU DOWNING, DJ AF DOWNING, DJ TI THE USE OF CONDITIONAL SIMULATION IN NUCLEAR-WASTE-SITE PERFORMANCE ASSESSMENT - DISCUSSION SO TECHNOMETRICS LA English DT Discussion ID MODELS RP DOWNING, DJ (reprint author), OAK RIDGE NATL LAB,MATH SCI SECT,OAK RIDGE,TN 37831, USA. NR 9 TC 0 Z9 0 U1 0 U2 0 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD MAY PY 1994 VL 36 IS 2 BP 147 EP 149 PG 3 WC Statistics & Probability SC Mathematics GA NH522 UT WOS:A1994NH52200004 ER PT J AU TORAN, L AF TORAN, L TI THE USE OF CONDITIONAL SIMULATION IN NUCLEAR-WASTE-SITE PERFORMANCE ASSESSMENT - DISCUSSION SO TECHNOMETRICS LA English DT Discussion ID HYDROGEOLOGICAL DECISION-ANALYSIS; HYDRAULIC CONDUCTIVITY; POROUS-MEDIA; SOLUTE TRANSPORT; SAND; VARIABILITY; DISPERSION RP TORAN, L (reprint author), OAK RIDGE NATL LAB,DIV ENVIRONM SCI,OAK RIDGE,TN 37831, USA. NR 15 TC 0 Z9 0 U1 0 U2 0 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD MAY PY 1994 VL 36 IS 2 BP 150 EP 152 PG 3 WC Statistics & Probability SC Mathematics GA NH522 UT WOS:A1994NH52200006 ER PT J AU RUTHERFORD, BM AF RUTHERFORD, BM TI THE USE OF CONDITIONAL SIMULATION IN NUCLEAR-WASTE-SITE PERFORMANCE ASSESSMENT - DISCUSSION SO TECHNOMETRICS LA English DT Discussion RP RUTHERFORD, BM (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 11 TC 0 Z9 0 U1 0 U2 0 PU AMER STATISTICAL ASSOC PI ALEXANDRIA PA 1429 DUKE ST, ALEXANDRIA, VA 22314 SN 0040-1706 J9 TECHNOMETRICS JI Technometrics PD MAY PY 1994 VL 36 IS 2 BP 152 EP 156 PG 5 WC Statistics & Probability SC Mathematics GA NH522 UT WOS:A1994NH52200007 ER PT J AU FANG, JY UPHAUS, RA STROEVE, P AF FANG, JY UPHAUS, RA STROEVE, P TI IMAGING OF STRUCTURED AND DISORDERED HEMICYANINE MONOLAYERS BY ATOMIC-FORCE MICROSCOPY SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 6th International Conference on Organized Molecular Films CY JUL 04-09, 1993 CL TROIS RIVIERES, CANADA ID LANGMUIR-BLODGETT-FILMS; 2ND-HARMONIC GENERATION; DYE; MULTILAYERS; ABSORPTION AB Monolayers of surface-active hemicyanine dyes have been extensively studied owing in part to their potential importance for fabrication it to non-linear optical m rials. In an effort to increase the dipole moment to a value larger than that present in the typical hemicyanine, a new compound was characterized, having the structure: (CH3)2N-C6H4-CH=CH-CH=CH-C6H4N+C22H45Br- (1) which contains a more extended pi-bonded system compared with some more commonly studied hemicyanines. It is known that hemicyanines may be present in various aggregated states as well as species having varying degrees of order when in monolayer form. For the new compound, monolayers could be produced having both ordered and disordered structures. On a pure water subphase, the new hemicyanine in a highly compressed monolayer had a narrow, blue-shifted absorption band with a maximum at 435 nm. Such a spectrum is characteristic of H-aggregate species. When the subphase contained cadmium chloride (1 x 10(3) M) the optical absorption band was similar to that seen in chloroform solution for disaggregated species, with a broad absorption band at 485 nm, shifting only slightly as the monolayer was progressively compressed. Atomic force microscopy visualizing the two different films indicated that monolayers transferred from pure water subphase appeared inhomogeneous, discontinous and indicative of island structures possibly present in the original spread monolayer, or formed during transfer. Monolayers formed on Cd2+-containing subphase were uniform except for some small surface defects. C1 UNIV CALIF DAVIS,DEPT CHEM ENGN,DAVIS,CA 95616. RP FANG, JY (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 9 TC 8 Z9 8 U1 0 U2 2 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD MAY 1 PY 1994 VL 243 IS 1-2 BP 450 EP 454 DI 10.1016/0040-6090(93)04071-Y PG 5 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA NM421 UT WOS:A1994NM42100031 ER PT J AU DELUCCHI, MA GREENE, DL WANG, MQ AF DELUCCHI, MA GREENE, DL WANG, MQ TI MOTOR-VEHICLE FUEL-ECONOMY - THE FORGOTTEN HYDROCARBON CONTROL STRATEGY SO TRANSPORTATION RESEARCH PART A-POLICY AND PRACTICE LA English DT Article AB For the past twenty years, energy and environmental analysts in the U.S. have been searching for ways to improve urban air quality and make the country less vulnerable to supply and price volatility in the world oil market. To improve urban air quality, the U.S. Environmental Protection Agency and a number of state air-quality agencies favor controls on emissions of non-methane hydrocarbons, which are one of the main contributors to ozone formation, and which are emitted along the entire fuel production-and-use chain, from drilling for oil through oil refining and gasoline marketing, to vehicle tailpipe emissions. To reduce oil consumption, some analysts and policy makers have suggested that the fuel economy of motor vehicles be increased substantially. These policies - to control emissions in order to improve air quality, and to increase fuel economy in order to reduce oil consumption - have always been considered separately in the U.S. In this paper we connect emission reduction policy with fuel-economy-improvement policy. We also examine a related issue: Does the side benefit of lower emissions due to improved fuel economy mean that fuel economy standards should be set even higher? Typically, when analysts estimate how high fuel economy standards should be, they compare the extra costs of efficiency-improving technology (including perhaps such things as reduced safety and performance) with the benefits of reduced fuel consumption. Such cost-benefit analyses have indicated an ''optimal'' level of fuel economy (where benefits balance costs) of between 30 and 40 mpg, depending on assumptions and methods. However, the analyses done to date have not counted the potential reduction in emissions as a benefit of improved fuel economy. We do so here, by assuming that the value of a ton of emissions eliminated by higher fuel economy is equal to the cost of controlling (eliminating) that ton by traditional control means. We find that adding the value of emission reductions to the benefit side of the cost-benefit analysis justifies raising fuel economy standards by an additional one mile per gallon only. C1 OAK RIDGE NATL LAB,CTR TRANSPORTAT ANAL,OAK RIDGE,TN 37831. ARGONNE NATL LAB,CTR TRANSPORTAT RES,ARGONNE,IL 60439. RP DELUCCHI, MA (reprint author), UNIV CALIF DAVIS,INST TRANSPORTAT STUDIES,DAVIS,CA 95616, USA. NR 42 TC 4 Z9 4 U1 0 U2 4 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD, ENGLAND OX5 1GB SN 0965-8564 J9 TRANSPORT RES A-POL JI Transp. Res. Pt. A-Policy Pract. PD MAY PY 1994 VL 28 IS 3 BP 223 EP 244 DI 10.1016/0965-8564(94)90019-1 PG 22 WC Economics; Transportation; Transportation Science & Technology SC Business & Economics; Transportation GA NK682 UT WOS:A1994NK68200005 ER PT J AU JAMIL, M BATTA, R MALON, DM AF JAMIL, M BATTA, R MALON, DM TI THE TRAVELING REPAIRPERSON HOME BASE LOCATION PROBLEM SO TRANSPORTATION SCIENCE LA English DT Article ID QUEUE AB This paper considers the problem of locating the home base of a traveling server on a network. Calls for service arrive solely at nodes via independent, time-homogeneous Poisson processes. Calls finding the server busy enter a finite capacity queue which is depleted in a First-Come-First-Served (FCFS) manner. The server travels from his/ her home base serving calls back-to-back, returning home only when he/she finds the system empty upon the completion of a service. The objective we consider is to minimize the average response time to an accepted call. The queueing system is analyzed via a busy period analysis, which uses a decoupling scheme to simplify the task of optimizing the home base location. Computational experience is discussed and a numerical example is presented. Generalizations of the model are also discussed. C1 SUNY BUFFALO,DEPT IND ENGN,BUFFALO,NY 14260. ARGONNE NATL LAB,ARGONNE,IL 60439. RP JAMIL, M (reprint author), RUTGERS STATE UNIV,SCH BUSINESS,CAMDEN,NJ 08102, USA. NR 17 TC 10 Z9 11 U1 0 U2 0 PU OPERATIONS RESEARCH SOC AMER PI LINTHICUM HTS PA 901 ELKRIDGE LANDING RD, STE 400, LINTHICUM HTS, MD 21090-2920 SN 0041-1655 J9 TRANSPORT SCI JI Transp. Sci. PD MAY PY 1994 VL 28 IS 2 BP 150 EP 161 DI 10.1287/trsc.28.2.150 PG 12 WC Operations Research & Management Science; Transportation; Transportation Science & Technology SC Operations Research & Management Science; Transportation GA NM183 UT WOS:A1994NM18300006 ER PT J AU PERRY, EM MORAN, MS AF PERRY, EM MORAN, MS TI AN EVALUATION OF ATMOSPHERIC CORRECTIONS OF RADIOMETRIC SURFACE TEMPERATURES FOR A SEMIARID RANGELAND WATERSHED SO WATER RESOURCES RESEARCH LA English DT Article ID SATELLITE; CALIBRATION; EMISSIVITY AB As part of an interdisciplinary effort to describe the hydrologic and surface energy balance of a semiarid rangeland watershed, remote and ground radiometric surface temperature measurements were collected at the Walnut Gulch experimental watershed near Tombstone, Arizona. To correct for atmospheric effects on the remotely sensed data, radiosondes were launched on and off the watershed, and the LOWTRAN7 radiative transfer model was used to evaluate these observed as well as two standard atmospheric profiles. Comparison of the results for five atmospheric profiles, for each of three days, showed no correlation between radiosonde location or launch time and resulting temperature corrections. Comparison of corrected temperatures using five different atmospheric profiles on each of two days with the corresponding ground-based radiometric temperatures demonstrated significant errors (greater than 2.0-degrees-C) as the atmospheric profiles generally yielded underestimates of ground radiometric temperatures. C1 USDA ARS, WATER CONSERVAT LAB, TUCSON, AZ 85719 USA. USDA ARS, BELTSVILLE AGR RES CTR, REMOTE SENSING RES LAB, BELTSVILLE, MD 20705 USA. RP PERRY, EM (reprint author), PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 20 TC 16 Z9 16 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1994 VL 30 IS 5 BP 1261 EP 1269 DI 10.1029/93WR03056 PG 9 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA NJ817 UT WOS:A1994NJ81700005 ER PT J AU MORENO, L TSANG, CF AF MORENO, L TSANG, CF TI FLOW CHANNELING IN STRONGLY HETEROGENEOUS POROUS-MEDIA - A NUMERICAL STUDY SO WATER RESOURCES RESEARCH LA English DT Article ID SOLUTE TRANSPORT; STOCHASTIC-ANALYSIS; SPATIAL MOMENTS; SINGLE FRACTURE; TRACER TEST; DISPERSION; MACRODISPERSION; VARIABILITY; GROUNDWATER; PREDICTION AB Flow and solute transport through porous media having strongly variable permeability were studied for parallel and convergent/divergent flows. The variation in hydraulic conductivity K causes (1) the fluid to flow through a porous medium along least resistive pathways and (2) solute dissolved in the fluid to be transported with widely differing velocities. Numerical simulations were performed to study flow and solute transport in a three-dimensional heterogeneous porous block. It is found that for a strongly heterogeneous medium the particles (or solutes) travel through the medium along preferred flow paths, which we call channels. These channels possess hydraulic properties that are different from those of the global porous medium and which are invariant regardless of the direction from which the hydraulic gradient is applied to the porous block. The log-hydraulic conductivities along these channels have a greater mean value and a smaller standard deviation than for the global porous medium. These differences or ''shifts'' were calculated as a function of the hydraulic conductivity variance of the global porous medium. Tracer breakthrough curves for a pulse injection were also calculated. For small standard deviations of the global hydraulic conductivity distribution, a peak in the breakthrough curve is found which spreads out around its peak value as the standard deviation is increased. However, as the standard deviation is increased further, a new peak emerges at a much earlier time. This may be the result of increasing channeling effects at large standard deviations. For the cage of a spherical pressure boundary around point tracer injection, the flow follows the usual divergent pattern only for small variations in hydraulic conductivity. When the standard deviation in log K is large, a significant portion of the flow becomes channelized; i.e., it tends toward a linear flow pattern. C1 LAWRENCE BERKELEY LAB,DIV EARTH SCI,BERKELEY,CA 94720. RP MORENO, L (reprint author), ROYAL INST TECHNOL,DEPT CHEM ENGN,S-10044 STOCKHOLM 70,SWEDEN. NR 28 TC 84 Z9 89 U1 1 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1994 VL 30 IS 5 BP 1421 EP 1430 DI 10.1029/93WR02978 PG 10 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA NJ817 UT WOS:A1994NJ81700020 ER PT J AU JOHNSON, TM DEPAOLO, DJ AF JOHNSON, TM DEPAOLO, DJ TI INTERPRETATION OF ISOTOPIC DATA IN GROUNDWATER-ROCK SYSTEMS - MODEL DEVELOPMENT AND APPLICATION TO SR ISOTOPE DATA FROM YUCCA MOUNTAIN SO WATER RESOURCES RESEARCH LA English DT Article ID CHEMICAL EVOLUTION; SOUTHERN NEVADA; MASS BALANCE; FLUID-FLOW; EXCHANGE; WATER; DIAGENESIS; SEAWATER; CALCITE; ORIGIN AB A model enabling extraction of hydrologic information from spatial and temporal patterns in measurements of isotope ratios in water-rock systems is presented. The model describes the evolution of isotope ratios in response to solute transport and water-rock interaction. In advective systems, a single dimensionless parameter (a Damkohler number, N(D)) dominates in determining the distance over which isotopic equilibrium between the water and rock is approached. Some isotope ratios act as conservative tracers (N(D) much less than 1), while others reflect only interaction with the local host rock (N(D) much greater than 1). If N(D) is close to one (i.e., the distance for equilibration is close to the length scale of observation), isotope ratio measurements can be used to determine N(D), which in turn may yield information concerning reaction rates, or spatial variations in water velocity. Zones of high velocity (e.g., as a result Of greater fracture density), or less reactive zones, may be identified through observation of their lower N(D) values. The model is applied to paleohydrologic interpretations of Sr isotope data from calcite fracture fillings in drill cores from Yucca Mountain, Nevada (Marshall et al., 1992). The results agree with other studies suggesting ''fast path'' transport in the unsaturated zone. Also, we find that the data do not give a conclusive indication of paleowater table elevation because of the effects of water-rock interaction. C1 LAWRENCE BERKELEY LAB,DIV EARTH SCI,BERKELEY,CA 94720. RP JOHNSON, TM (reprint author), UNIV CALIF BERKELEY,DEPT GEOL & GEOPHYS,BERKELEY CTR ISOTOPE GEOCHEM,BERKELEY,CA 94720, USA. RI Johnson, Thomas/A-2740-2008 OI Johnson, Thomas/0000-0003-1620-1408 NR 53 TC 72 Z9 74 U1 1 U2 11 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1994 VL 30 IS 5 BP 1571 EP 1587 DI 10.1029/94WR00157 PG 17 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA NJ817 UT WOS:A1994NJ81700033 ER PT J AU WILLIAMS, GP AF WILLIAMS, GP TI A PERFORMANCE COMPARISON OF SCALAR, VECTOR, AND CONCURRENT VECTOR COMPUTERS INCLUDING SUPERCOMPUTERS FOR MODELING TRANSPORT OF REACTIVE CONTAMINANTS IN GROUNDWATER - COMMENT SO WATER RESOURCES RESEARCH LA English DT Note C1 NORTHWESTERN UNIV,DEPT CIVIL ENGN,EVANSTON,IL 60201. RP WILLIAMS, GP (reprint author), ARGONNE NATL LAB,DIV ENVIRONM ASSESSMENT & INFORMAT SCI,9700 S CASS AVE,ARGONNE,IL 60439, USA. RI Williams, Gustavious/P-7252-2014 OI Williams, Gustavious/0000-0002-2781-0738 NR 6 TC 1 Z9 1 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD MAY PY 1994 VL 30 IS 5 BP 1635 EP 1637 DI 10.1029/94WR00158 PG 3 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA NJ817 UT WOS:A1994NJ81700044 ER PT J AU RAO, GR LEE, EH MANSUR, LK AF RAO, GR LEE, EH MANSUR, LK TI WEAR PROPERTIES OF ARGON IMPLANTED POLY(ETHER ETHER KETONE) SO WEAR LA English DT Article ID SURFACE-PROPERTIES; PEEK COMPOSITES; BEHAVIOR; POLYETHERETHERKETONE; HARDNESS AB The sliding wear properties of Ar+-implanted poly(ether ether ketone) (PEEK) using nylon 66 and SAE 52100 high carbon chrome steel ball counterfaces have been investigated in this study. PEEK was implanted with 1 MeV Ar+ to fluences of 5 x 10(18), 1 x 10(19) and 5 x 10(19) ions m-2. Reciprocating sliding wear tests were conducted using a 1 N normal load, 3 mm sliding distance and 100 cpm frequency for 10 000 sliding cycles. The implantation significantly improved the wear properties of PEEK for the nylon ball tests to the extent that no wear tracks were evident on the PEEK surface. This was attributed to significant strengthening of the PEEK surface by ion beam induced cross-linking which, in tum, caused corresponding wear of the softer nylon counterface. For the steel counterface tests, the intermediate-fluence implanted specimen showed no wear damage on the surface. There was wear damage for the unimplanted, lower and higher fluence implanted specimens. The results indicate that the best wear properties appeared at some optimum level of ion-beam induced cross-linking of PEEK for the steel counterface. Friction coefficient data were correlated with the observed wear behavior. Mechanisms of energy transfer from the energetic ions to the polymer molecules were analyzed to explain the wear improvements. This study shows that ion implantation is a promising technique for significant improvements in the tribological properties of PEEK. RP RAO, GR (reprint author), OAK RIDGE NATL LAB,DIV MET & CERAM,POB 2008,OAK RIDGE,TN 37831, USA. NR 16 TC 8 Z9 10 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0043-1648 J9 WEAR JI Wear PD MAY PY 1994 VL 174 IS 1-2 BP 103 EP 109 DI 10.1016/0043-1648(94)90091-4 PG 7 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA NN747 UT WOS:A1994NN74700012 ER PT J AU ARVAY, Z ZIMANYI, J CSORGO, T DOVER, CB HEINZ, U AF ARVAY, Z ZIMANYI, J CSORGO, T DOVER, CB HEINZ, U TI PRODUCTION OF STRANGE CLUSTERS BY QUARK-GLUON-PLASMA FRAGMENTATION SO ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI LA English DT Article ID HEAVY-ION COLLISIONS; NUCLEAR COLLISIONS; MATTER DROPLETS; SEPARATION; EVOLUTION; KINETICS; MODEL AB We discuss the production of strange quark clusters in high energy heavy ion reactions in which a Quark-Gluon-Plasma (QGP) intermediate state is excited. A microscopic fission-chain model (PHASER) has been constructed for the description of QGP rehadronization. Color fluctuations, QQBAR pair production and energy fragmentation have been taken into account. We determined the spin-flavor degeneracy factors and the formation factors for multibaryon quark clusters. Baryon, antibaryon and meson yields have been estimated, as well as those of light multi-strange quark clusters. C1 BROOKHAVEN NATL LAB,UPTON,NY 11973. UNIV REGENSBURG,INST THEORET PHYS,D-93040 REGENSBURG,GERMANY. RP ARVAY, Z (reprint author), CENT RES INST PHYS,POB 49,H-1525 BUDAPEST 114,HUNGARY. RI Csorgo, Tamas/I-4183-2012 NR 30 TC 3 Z9 3 U1 0 U2 2 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0939-7922 J9 Z PHYS A-HADRON NUCL JI Z. Phys. A.-Hadrons Nuclei PD MAY PY 1994 VL 348 IS 3 BP 201 EP 210 DI 10.1007/BF01291918 PG 10 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA NR033 UT WOS:A1994NR03300007 ER PT J AU BERNASCONI, A MOMBELLI, M FISK, Z OTT, HR AF BERNASCONI, A MOMBELLI, M FISK, Z OTT, HR TI LOW-TEMPERATURE TRANSPORT-PROPERTIES OF UCU5 SO ZEITSCHRIFT FUR PHYSIK B-CONDENSED MATTER LA English DT Article ID HEAVY AB The electrical resistivity rho(T) and the thermal conductivity lambda(T) have been measured for UCu5 in the temperature range between 0.02 and 20 K. Two distinct anomalies in rho(T) are due to previously established phase transitions at approximately 15 and 1 K, respectively. They indicate considerable changes in the electronic structure of this compound, implying sizeable truncations of the Fermi surface with decreasing temperature at both transitions. In almost the entire covered temperature range the thermal conductivity is dominated by phonon contributions. Its temperature dependence is fairly well reproduced by a calculation considering phonon scattering by electrons and by point defects, At very low temperatures, as T approaches 0 K, the Wiedemann-Franz law lambda(e) . rho = L0 T, where lambda(e) is the electronic part of lambda(T) and L0 is the Lorenz number, is almost perfectly fulfilled. C1 LOS ALAMOS NATL LAB, DIV MAT SCI & TECHNOL, LOS ALAMOS, NM 87545 USA. RP BERNASCONI, A (reprint author), SWISS FED INST TECHNOL, FESTKORPERPHYS LAB, CH-8093 ZURICH, SWITZERLAND. NR 14 TC 9 Z9 9 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0722-3277 J9 Z PHYS B CON MAT JI Z. Phys. B-Condens. Mat. PD MAY PY 1994 VL 94 IS 4 BP 423 EP 429 DI 10.1007/BF01317404 PG 7 WC Physics, Condensed Matter SC Physics GA NP165 UT WOS:A1994NP16500009 ER PT J AU WHITMORE, JJ PERSI, F TOOTHACKER, WS ELCOMBE, PA HILL, JC NEALE, WW WALKER, WD KOWALD, W LUCAS, P VOYVODIC, L AMMAR, R COPPAGE, D DAVIS, R GRESS, J KANEKAL, S KWAK, N BISHOP, JM BISWAS, NN CASON, NM KENNEY, VP MATTINGLY, MCK RUCHTI, RC SHEPHARD, WD AF WHITMORE, JJ PERSI, F TOOTHACKER, WS ELCOMBE, PA HILL, JC NEALE, WW WALKER, WD KOWALD, W LUCAS, P VOYVODIC, L AMMAR, R COPPAGE, D DAVIS, R GRESS, J KANEKAL, S KWAK, N BISHOP, JM BISWAS, NN CASON, NM KENNEY, VP MATTINGLY, MCK RUCHTI, RC SHEPHARD, WD TI INCLUSIVE CHARGED PION-PRODUCTION IN HADRON-NUCLEUS INTERACTIONS AT 100 AND 320 GEV/C SO ZEITSCHRIFT FUR PHYSIK C-PARTICLES AND FIELDS LA English DT Article ID CRISIS DETECTOR; GEV-C; COLLISIONS; IDENTIFICATION; PERFORMANCE; IONIZATION; PARTICLES; PROTONS AB An experiment has been performed with the Fermilab 30-inch bubble chamber and Downstream Particle Identifier to study inclusive charged pion production in the high energy interactions of pi+/-, K+, p and pBAR with thin foils of magnesium, silver and gold. The laboratory rapidity and transverse momentum distributions are presented separately for pi+ and pi- production. Comparisons are made with data from hadron-proton interactions and the A dependence of the cross sections in the different kinematic regions is discussed. We investigate the dependence of the cross sections on the number of observed protons ejected from the nucleus. By using our pi- A data from two different beam energies, we study the energy dependence of these spectra. Comparisons are made with the VENUS string model Monte Carlo. C1 PENN STATE UNIV,MT ALTO,PA 17237. UNIV CAMBRIDGE,CAMBRIDGE CB3 0HE,ENGLAND. DUKE UNIV,DURHAM,NC 27706. FERMILAB NATL ACCELERATOR LAB,BATAVIA,IL 60510. UNIV KANSAS,LAWRENCE,KS 66045. UNIV NOTRE DAME,NOTRE DAME,IN 46556. RP WHITMORE, JJ (reprint author), PENN STATE UNIV,DEPT PHYS,ELEMENTARY PARTICLE SCI LAB,UNIV PK,PA 16802, USA. NR 28 TC 10 Z9 10 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 SN 0170-9739 J9 Z PHYS C PART FIELDS JI Z. Phys. C-Part. Fields PD MAY PY 1994 VL 62 IS 2 BP 199 EP 227 DI 10.1007/BF01560238 PG 29 WC Physics, Particles & Fields SC Physics GA NQ098 UT WOS:A1994NQ09800002 ER PT J AU KHAKHALIN, SY BRYUNETKIN, BA SKOBELEV, IY FAENOV, AY NILSEN, D OSTERKHELD, A PIKUZ, SA AF KHAKHALIN, SY BRYUNETKIN, BA SKOBELEV, IY FAENOV, AY NILSEN, D OSTERKHELD, A PIKUZ, SA TI DIELECTRON SATELLITES OF RESONANCE LINES OF NE-LIKE IONS IN A HIGH-TEMPERATURE PLASMA SO ZHURNAL EKSPERIMENTALNOI I TEORETICHESKOI FIZIKI LA Russian DT Article ID X-RAY-SPECTRA; LASER; TRANSITIONS C1 LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. PN LEBEDEV PHYS INST, MOSCOW 117924, RUSSIA. RP KHAKHALIN, SY (reprint author), ALL RUSSIAN PHYS TECH & RADIO TECH MEASUREMENTS RE, SCI IND ASSOC, MENDELEYEVSK 141570, RUSSIA. RI Pikuz, Sergey/M-8231-2015 NR 18 TC 2 Z9 2 U1 0 U2 0 PU MEZHDUNARODNAYA KNIGA PI MOSCOW PA 39 DIMITROVA UL., 113095 MOSCOW, RUSSIA SN 0044-4510 J9 ZH EKSP TEOR FIZ+ JI Zhurnal Eksperimentalnoi Teor. Fiz. PD MAY PY 1994 VL 105 IS 5 BP 1181 EP 1198 PG 18 WC Physics, Multidisciplinary SC Physics GA NP398 UT WOS:A1994NP39800007 ER PT J AU SORENSEN, SP CHAO, WQ AF SORENSEN, SP CHAO, WQ TI MONTE-CARLO CODE ODIN AND ENERGY DENSITY ANALYSIS IN RELATIVISTIC HEAVY-ION COLLISIONS SO COMMUNICATIONS IN THEORETICAL PHYSICS LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS AB The energy density reached in relativistic heavy ion collisions is analyzed based on the Monte Carlo code ODIN. The effect of different parameters in ODIN code on the energy density is investigated. The results show that the actually reached energy density is lower than Bjorken's estimation due to the finite collision time. C1 ACAD SINICA,INST HIGH ENERGY PHYS,POB 9184,BEIJING 100039,PEOPLES R CHINA. UNIV TENNESSEE,KNOXVILLE,TN 37996. CCAST,WORLD LAB,BEIJING 100080,PEOPLES R CHINA. OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. NR 9 TC 7 Z9 7 U1 0 U2 0 PU HUAZHONG UNIV SCI TECH PRESS PI WUHAN PA WUHAN, PEOPLES R CHINA SN 0253-6102 J9 COMMUN THEOR PHYS JI Commun. Theor. Phys. PD APR 30 PY 1994 VL 21 IS 3 BP 317 EP 326 PG 10 WC Physics, Multidisciplinary SC Physics GA NM500 UT WOS:A1994NM50000010 ER PT J AU BHOWMIK, PK BEAUCAGE, G BHATTACHARYA, SK LENZ, RW AF BHOWMIK, PK BEAUCAGE, G BHATTACHARYA, SK LENZ, RW TI CRYSTALLINITY OF FULLY AROMATIC THERMOTROPIC POLYESTERS OF 3,3'-BIS (PHENYL)-4,4'-BIPHENOL AND 1,1'-BINAPHTHYL-4,4'-DIOL SO JOURNAL OF POLYMER SCIENCE PART B-POLYMER PHYSICS LA English DT Article DE DEGREE OF CRYSTALLINITY; FULLY AROMATIC; THERMOTROPIC HOMOPOLYESTER; THERMOTROPIC COPOLYESTER; X-RAY DIFFRACTION ID MAIN-CHAIN; 4-HYDROXYBENZOIC ACID; COPOLYESTERS AB The degree of crystallinity of as-made fully aromatic, thermotropic polyesters was determined for two different series of polymers, each of which contained a symmetric monomer having either pendant phenyl groups or fused aromatic rings by the WAXD technique. All of the homopolymers had a high degree of crystallinity in spite of bulky substituents attached to the mesogenic moiety. Surprisingly, the homopolymer of 2,6-naphthalenedicarboxylic acid with each of the monomers had a higher degree of crystallinity and T(m) than those of the homopolymer of terephthalic acid with each of the respective monomers. As expected, on copolymerization with 30 mol % of either 4-hydroxybenzoic acid or 6-hydroxy-2-naphthoic acid, all of the resulting copolymers had a much lower degree of crystallinity and T(m)/T(f) values compared to those of the respective homopolymers in each series. (C) 1994 John Wiley & Sons, Inc. C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. HINDUSTAN LEVER LTD,RES CTR,BOMBAY 400099,INDIA. UNIV MASSACHUSETTS,DEPT POLYMER SCI & ENGN,AMHERST,MA 01003. RP BHOWMIK, PK (reprint author), UNIV DETROIT MERCY,DEPT CHEM,4001 W MCNICHOLS RD,POB 19900,DETROIT,MI 48219, USA. RI Bhowmik, Pradip/B-7673-2008 NR 21 TC 8 Z9 8 U1 0 U2 1 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0887-6266 J9 J POLYM SCI POL PHYS JI J. Polym. Sci. Pt. B-Polym. Phys. PD APR 30 PY 1994 VL 32 IS 6 BP 1023 EP 1031 DI 10.1002/polb.1994.090320608 PG 9 WC Polymer Science SC Polymer Science GA NB408 UT WOS:A1994NB40800008 ER PT J AU TRIVEDI, R AF TRIVEDI, R TI MICROSTRUCTURE CHARACTERISTICS OF RAPIDLY SOLIDIFIED ALLOYS SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT NATO Advanced Research Workshop on Undercooled Metallic Melts: Properties, Solidification and Metastable Phases CY JUN 06-12, 1993 CL IL CIOCCO CENTRO INT SPA, IL CIOCCO, ITALY SP NATO, SCI AFFAIRS DIV, EUROPEAN SPACE AGCY, NASA, GERMAN AEROSP RES ESTAB, GERMAN SPACE AGCY, CNR, DORNIER GMBH HO IL CIOCCO CENTRO INT SPA ID DENDRITIC GROWTH; CRYSTAL-GROWTH; NI MELTS; INSTABILITIES; INTERFACE; MODEL AB The microstructural characteristics of rapidly solidified materials were examined in terms of the effect of high velocity on the physical processes that govern microstructure formation. Under rapid solidification conditions, non-equilibrium conditions at the interface and a modified diffusional instability condition play critical roles in the selection of morphology and its microstructural scales. These effects were examined in terms of their influence on the physical processes. Appropriate characteristic lengths of physical processes for rapid solidification were developed, and relationships obtained for low and high growth rate conditions which characterize microstructural transition conditions and microstructural scales of cellular, dendritic and eutectic structures under free and constrained growth conditions. It is shown that all the results at low and high growth rates can be represented by unified expression in terms of redefined characteristic lengths. C1 IOWA STATE UNIV SCI & TECHNOL,MAT SCI & ENGN,AMES,IA 50011. RP TRIVEDI, R (reprint author), US DOE,AMES LAB,AMES,IA 50011, USA. NR 22 TC 16 Z9 16 U1 1 U2 4 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD APR 30 PY 1994 VL 178 IS 1-2 BP 129 EP 135 DI 10.1016/0921-5093(94)90531-2 PG 7 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA NH615 UT WOS:A1994NH61500024 ER PT J AU MACDONALD, LE DURBIN, RK DUNN, JJ MCALLISTER, WT AF MACDONALD, LE DURBIN, RK DUNN, JJ MCALLISTER, WT TI CHARACTERIZATION OF 2 TYPES OF TERMINATION SIGNAL FOR BACTERIOPHAGE-T7 RNA-POLYMERASE SO JOURNAL OF MOLECULAR BIOLOGY LA English DT Article DE TRANSCRIPTION; PHAGE RNA POLYMERASE; TERMINATION ID TRANSCRIPTION TERMINATION; T7-RNA POLYMERASE; DNA; PROMOTER; INVITRO; PROCESSIVITY; EFFICIENCY; MECHANISM; SEQUENCE; ELEMENTS C1 SUNY HLTH SCI CTR,MORSE INST MOLEC GENET,DEPT MICROBIOL & IMMUNOL,BROOKLYN,NY 11203. BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973. FU NIGMS NIH HHS [GM38147] NR 33 TC 60 Z9 61 U1 0 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON, ENGLAND NW1 7DX SN 0022-2836 J9 J MOL BIOL JI J. Mol. Biol. PD APR 29 PY 1994 VL 238 IS 2 BP 145 EP 158 DI 10.1006/jmbi.1994.1277 PG 14 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA NH632 UT WOS:A1994NH63200003 PM 8158645 ER PT J AU WAKATSUKI, S KIMURA, Y STOECKENIUS, W GILLIS, N ELIEZER, D HODGSON, KO DONIACH, S AF WAKATSUKI, S KIMURA, Y STOECKENIUS, W GILLIS, N ELIEZER, D HODGSON, KO DONIACH, S TI BLUE FORM OF BACTERIORHODOPSIN AND ITS ORDER-DISORDER TRANSITION DURING DEHYDRATION SO BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS LA English DT Article DE TIME-RESOLVED SMALL-ANGLE X-RAY DIFFRACTION; BLUE MEMBRANE; DEIONIZED PURPLE MEMBRANE; ORDER-DISORDER TRANSITION; RADIAL AUTOCORRELATION FUNCTION; DEHYDRATION ID X-RAY-DIFFRACTION; SOLID-STATE C-13; PURPLE MEMBRANE; NEUTRON-DIFFRACTION; HALOBACTERIUM-HALOBIUM; ABSORPTION-SPECTRUM; PH; INTERMEDIATE; CHROMOPHORE; HYDRATION AB Freshly-prepared blue membranes from Halobacterium halobium, previously reported to be disordered, are shown to have a distinct crystal lattice structure, slightly different from the native form. The lattice of the blue form is disrupted irreversibly when dehydrated. The disorder process was observed using time-resolved small-angle X-ray diffraction and analyzed by radial autocorrelation functions. The diffraction peaks of the in-plane lattice first sharpen and increase due to improved membrane orientation, then the trimer lattice becomes disordered and the unit cell dimension decreases by 1.8 Angstrom. In contrast, dehydration of purple membranes does not disorder the lattice, and the unit cell dimension shrinks by only 1.0 Angstrom. Comparisons of radial autocorrelation functions for the blue membrane during drying show drastic loss of inter-trimer, long-range correlation while the intra-trimer, short-range correlations remain more or less unchanged. This suggests that the deionized protein trimers can maintain their overall structure during the dehydration, even though the lattice dimension decreases appreciably and the two-dimensional crystallinity is disrupted. C1 STANFORD UNIV,DEPT CHEM,STANFORD,CA 94305. STANFORD UNIV,STANFORD SYNCHROTRON RADIAT LAB,STANFORD,CA 94305. UNIV CALIF SAN FRANCISCO,CARDIOVASC RES INST,SAN FRANCISCO,CA 94143. STANFORD UNIV,DEPT APPL PHYS,STANFORD,CA 94305. STANFORD UNIV,DEPT PHYS,STANFORD,CA 94305. FU NCRR NIH HHS [RR1209]; NIGMS NIH HHS [GM27057] NR 37 TC 5 Z9 5 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0005-2728 J9 BBA-BIOENERGETICS JI Biochim. Biophys. Acta-Bioenerg. PD APR 28 PY 1994 VL 1185 IS 2 BP 160 EP 166 DI 10.1016/0005-2728(94)90206-2 PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA NK097 UT WOS:A1994NK09700003 PM 8167134 ER PT J AU THOMAS, RC TANGYUNYONG, P HOUSTON, JE MICHALSKE, TA CROOKS, RM AF THOMAS, RC TANGYUNYONG, P HOUSTON, JE MICHALSKE, TA CROOKS, RM TI CHEMICALLY-SENSITIVE INTERFACIAL FORCE MICROSCOPY - CONTACT POTENTIAL MEASUREMENTS OF SELF-ASSEMBLING MONOLAYER FILMS SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Letter ID ORGANIC-SURFACES; GOLD AB We report contact potential difference (CPD) measurements of n-alkanethiol self-assembling monolayers (SAMs) adsorbed to Au substrates using an organomercaptan-modified Au probe. We perform experiments by applying a triangular-sweep voltage between the sample and probe while measuring the resulting electrostatic force. The interfacial force microscope permits us to keep the probe/sample distance rigidly fixed, which allows us to directly measure the electrostatic force at a constant interfacial separation. The CPD is determined by measuring the applied potential necessary to null the electric field and eliminate the interfacial force between the two surfaces. We show that CPD values obtained using Au probes modified with methyl-terminated SAMs are stable and reproducible, whereas identical unmodified probes yield highly variable data. Our experimentally determined CPD values are in qualitative agreement with calculated CPDs for several different omega-terminated SAMs. C1 SANDIA NATL LABS,DEPT SURFACE & INTERFACE SCI,ALBUQUERQUE,NM 87185. UNIV NEW MEXICO,DEPT CHEM,ALBUQUERQUE,NM 87131. NR 18 TC 61 Z9 62 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 28 PY 1994 VL 98 IS 17 BP 4493 EP 4494 DI 10.1021/j100068a002 PG 2 WC Chemistry, Physical SC Chemistry GA NJ538 UT WOS:A1994NJ53800002 ER PT J AU REDDY, NRS VANAMERONGEN, H KWA, SLS VANGRONDELLE, R SMALL, GJ AF REDDY, NRS VANAMERONGEN, H KWA, SLS VANGRONDELLE, R SMALL, GJ TI LOW-ENERGY EXCITON LEVEL STRUCTURE AND DYNAMICS IN LIGHT-HARVESTING COMPLEX-II TRIMERS FROM THE CHL A/B ANTENNA COMPLEX OF PHOTOSYSTEM-II SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID PHOTOSYNTHETIC REACTION CENTERS; BACTERIOCHLOROPHYLL-A-PROTEIN; BACTERIAL REACTION CENTERS; ELECTRON-DONOR STATE; RHODOBACTER-SPHAEROIDES; RHODOPSEUDOMONAS-VIRIDIS; LHC-II; PROSTHECOCHLORIS-AESTUARII; SPECTROSCOPIC PROPERTIES; DISPERSIVE KINETICS AB Nonphotochemical hole-burned spectra obtained as a function of burn wavelength at 4.2 K are reported for the isolated LHC II peripheral antenna complex of photosystem II. The lowest-energy state of the trimer complex is shown to lie at 680 nm, 4 nm below the most intense Chl a band at 676 nm. The linear electron-phonon coupling for the 680-nm state is characterized and used to predict that its fluorescence origin should lie at 681 nm, precisely coincident with the observed origin at 4.2 K. The 680-nm band carries the equivalent absorption strength of about one chlorophyll a molecule per C-3 trimer complex, which contains about 27 chlorophyll a molecules. The 680-nm absorption band possesses an inhomogeneous width of similar to 120 cm(-1), and its zero-phonon line distribution function is largely uncorrelated with those of the higher-energy states. Zero-phonon hole widths are used to determine that the fluorescent 680-nm state dephases in 10 ps at 4.2 K. An interpretation of this dephasing is given in terms of the trimer of subunits structure. Based on the satellite hole structure observed upon hole burning into the 680-nm state, two new states at 674 and 678 nm are identified. The possibility that these three states are excitonically correlated is considered. The observed trend in the zero-phonon hole burning efficiency as a function of burn frequency is qualitatively consistent with the states at energies higher than 680 nm having ultrashort lifetimes at 4.2 K. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. FREE UNIV AMSTERDAM,DEPT PHYS & ASTRON,AMSTERDAM,NETHERLANDS. RI van Amerongen, Herbert/J-9483-2016 OI van Amerongen, Herbert/0000-0002-9783-2895 NR 55 TC 69 Z9 72 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 28 PY 1994 VL 98 IS 17 BP 4729 EP 4735 DI 10.1021/j100068a040 PG 7 WC Chemistry, Physical SC Chemistry GA NJ538 UT WOS:A1994NJ53800040 ER PT J AU DU, M XIE, XL METS, L FLEMING, GR AF DU, M XIE, XL METS, L FLEMING, GR TI DIRECT OBSERVATION OF ULTRAFAST ENERGY-TRANSFER PROCESSES IN LIGHT-HARVESTING COMPLEX-II SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID CHLOROPHYLL-A/B PROTEIN; CORE ANTENNA; LHC-II; 3-DIMENSIONAL STRUCTURE; EXCITATION TRANSFER; MOLECULAR PAIRS; PHOTOSYSTEM-II; TRANSFER RATES; FLUORESCENCE; DYNAMICS AB A femtosecond fluorescence upconversion apparatus was used to study the isotropic and anisotropic fluorescence dynamics in the chlorophyll a/b light harvesting complex II of a PS I-PS II double-deficiency strain, C2, of Chlamydomonas reinhardtii. The fluorescence depolarization measurements reveal nonexponential behavior that is well described by a sum of two exponentials with time constants of 250-300 fs and 5-12 ps. The nonexponential behavior likely arises from intracomplex heterogeneity in the structural and spectral factors that control energy-transfer dynamics. Isotropic fluorescence measurements reveal a rise time of 250-300 fs at both 700 and 710 nm, but not at 730 nm. We discuss the implications of our data for LHC II structural organization. C1 UNIV CHICAGO, DEPT CHEM, CHICAGO, IL 60637 USA. UNIV CHICAGO, JAMES FRANCK INST, CHICAGO, IL 60637 USA. UNIV CHICAGO, DEPT MOLEC GENET & CELL BIOL, CHICAGO, IL 60637 USA. PACIFIC NW LAB, MOLEC SCI RES CTR, RICHLAND, WA 99352 USA. NR 36 TC 70 Z9 77 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 28 PY 1994 VL 98 IS 17 BP 4736 EP 4741 DI 10.1021/j100068a041 PG 6 WC Chemistry, Physical SC Chemistry GA NJ538 UT WOS:A1994NJ53800041 ER PT J AU SATAKA, M IMAI, M YAMAZAKI, Y KOMAKI, K KAWATSURA, K KANAI, Y TAWARA, H SCHULTZ, DR REINHOLD, CO AF SATAKA, M IMAI, M YAMAZAKI, Y KOMAKI, K KAWATSURA, K KANAI, Y TAWARA, H SCHULTZ, DR REINHOLD, CO TI PROJECTILE CHARGE-STATE DEPENDENCE OF BINARY ELECTRON PRODUCTION FOR 1-MEV U(-1) AU(Q+) (Q=12-37) ION IMPACT ON HE SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Letter ID QUASI-FREE ELECTRONS; ATOM COLLISIONS; CROSS-SECTIONS; ELASTIC-SCATTERING; IONIZATION; PEAK; 0-DEGREES; EMISSION; RYDBERG; TARGETS AB The absolute cross section for the production of binary encounter electrons has been studied at zero degree for highly charged, clothed ions. Experimental and theoretical results for 1 MeV u-1 Au(q+) (q = 12-37) colliding with helium are presented. It is found experimentally that as the charge state of the incident ion is increased (1) the binary peak magnitude increases, (2) the electron energy at which the peak occurs decreases, and (3) the peak broadens. Classical trajectory Monte Carlo (CTMC) calculations are found to give good account for the magnitude and the shift to lower electron energy of the peak. the continuum distorted wave-eikonal initial state (CDW-EIS) approximation is shown to yield cross sections which are much smaller in magnitude than the experiments, but to reproduce well the relative magnitudes and shapes of the peaks for these ions. It is noted that the increase in the binary peak magnitude with increasing ionic charge state is in distinction to previous measurements which showed enhancement of the binary peak with decreasing charge state for clothed ions. C1 UNIV TOKYO,COLL ARTS & SCI,INST PHYS,TOKYO 153,JAPAN. KYOTO INST TECHNOL,FAC ENGN & DESIGN,DEPT CHEM,SAKYO KU,KYOTO 606,JAPAN. INST PHYS & CHEM RES RIKEN,WAKO,SAITAMA 35101,JAPAN. NATL INST FUS SCI,NAGOYA 46401,JAPAN. OAK RIDGE NATL LAB,DIV PHYS,OAK RIDGE,TN 37831. UNIV TENNESSEE,DEPT PHYS & ASTRON,KNOXVILLE,TN 37996. RP SATAKA, M (reprint author), JAPAN ATOM ENERGY RES INST,DEPT MAT SCI & ENGN,TOKAI,IBARAKI 31911,JAPAN. RI Yamazaki, Yasunori/N-8018-2015; Kanai, Yasuyuki/A-2599-2009 OI Yamazaki, Yasunori/0000-0001-5712-0853; NR 35 TC 7 Z9 7 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD APR 28 PY 1994 VL 27 IS 8 BP L171 EP L177 DI 10.1088/0953-4075/27/8/007 PG 7 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA NK149 UT WOS:A1994NK14900007 ER PT J AU HUGHES, RJ AF HUGHES, RJ TI ATOMIC PHYSICS - NEW LIGHT ON ANTIPROTONIC ATOMS SO NATURE LA English DT Editorial Material ID METASTABLE STATES; HELIUM RP HUGHES, RJ (reprint author), LOS ALAMOS NATL LAB,DIV PHYS,LOS ALAMOS,NM 87545, USA. NR 10 TC 0 Z9 0 U1 0 U2 0 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD APR 28 PY 1994 VL 368 IS 6474 BP 813 EP 814 DI 10.1038/368813a0 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA NH717 UT WOS:A1994NH71700047 ER PT J AU LIU, J WONG, CY SHIH, CC WANG, RC AF LIU, J WONG, CY SHIH, CC WANG, RC TI ONE-PARTICLE FRAGMENTATION FUNCTIONS IN THE MASSLESS SCHWINGER MODEL SO PHYSICS LETTERS B LA English DT Article ID LIGHT-CONE AB One-particle fragmentation functions in the massless Schwinger model are calculated using the bosonization formula. C1 UNIV TENNESSEE,KNOXVILLE,TN 37996. UNIV SCI & TECHNOL CHINA,HEFEI,PEOPLES R CHINA. RP LIU, J (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. OI Wong, Cheuk-Yin/0000-0001-8223-0659 NR 16 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 28 PY 1994 VL 326 IS 1-2 BP 154 EP 160 DI 10.1016/0370-2693(94)91207-6 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NJ361 UT WOS:A1994NJ36100026 ER PT J AU MOUNTFORD, HS MACQUEEN, DB LI, AP OTVOS, JW CALVIN, M FRANKEL, RB SPREER, LO AF MOUNTFORD, HS MACQUEEN, DB LI, AP OTVOS, JW CALVIN, M FRANKEL, RB SPREER, LO TI SPECTROSCOPIC AND ELECTROCHEMICAL CHARACTERIZATION OF A BIS-MACROCYCLIC DIIRON COMPOUND SO INORGANIC CHEMISTRY LA English DT Article ID CHARGE-TRANSFER; COMPLEXES; IRON(II); LIGANDS; RUTHENIUM(II); OSMIUM(II); REDOX; SPIN AB The properties of the complex [Fe2(C20H36N8)(CH3CN)4](ClO4)4 have been extensively investigated by optical and Mossbauer spectroscopy as well as by electrochemistry. The binucleating ligand TIED (tetraiminoethylene dimacrocycle) is an exceptionally good pi acceptor as indicated by the Mossbauer spectrum, which shows a low value for the center shift and a high value for the quadrupole splitting parameter. This behavior is consistent with the unusually high value for the first oxidation potential (1.18 V vs NHE) since Fe2+ is a much better pi donor than Fe3+. Also, extensive back-bonding from iron to an unoccupied pi* orbital of the ligand may help produce the very short Fe-N(imine) distance of 1.89 angstrom that was found in the complex. Electrochemical oxidation apparently occurs at the metal centers, since the potential shows a large solvent dependence, which we attribute to axial ligand exchange by coordinating solvent molecules. Electrochemical reduction, while formally occurring at the ligand, shows indications of extensive mixing of ligand and metal orbitals. There is a change from two, well-separated one-electron reductions in CH3CN to closely overlapping reductions in DMF and H2O. Another indication of orbital mixing is the fact that substitution of Ni for Fe in the complex causes a large shift of 780 mV in the first ligand reduction potential. C1 UNIV PACIFIC,DEPT CHEM,STOCKTON,CA 95211. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. CALIF POLYTECH STATE UNIV SAN LUIS OBISPO,DEPT PHYS,SAN LUIS OBISPO,CA 93407. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. NR 25 TC 27 Z9 27 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD APR 27 PY 1994 VL 33 IS 9 BP 1748 EP 1752 DI 10.1021/ic00087a005 PG 5 WC Chemistry, Inorganic & Nuclear SC Chemistry GA NJ344 UT WOS:A1994NJ34400005 ER PT J AU SPREER, LO LI, AP MACQUEEN, DB ALLAN, CB OTVOS, JW CALVIN, M FRANKEL, RB PAPAEFTHYMIOU, GC AF SPREER, LO LI, AP MACQUEEN, DB ALLAN, CB OTVOS, JW CALVIN, M FRANKEL, RB PAPAEFTHYMIOU, GC TI CHARACTERIZATION OF A DELOCALIZED MIXED-VALENCE BIS-MACROCYCLIC DIIRON COMPOUND SO INORGANIC CHEMISTRY LA English DT Article ID COMPLEX; SYSTEM AB A mixed-valence Fe(II)/Fe(III) compound has been obtained by electrochemical oxidation of a bis-macrocyclic Fe(II)/Fe(II) complex. The binucleating ligand provides a delocalized pi system that facilitates electronic interaction between the metals. The Mossbauer spectrum of the mixed-valence compound consists of a single quadrupole-split doublet down to 4 K which establishes the equivalency of the two iron atoms. The cyclic voltammogram of the Fe(II)/Fe(II) species in rigorously dried acetonitrile shows two reversible oxidations with DELTAE1/2 = 500 mV. This corresponds to a comproportionation constant for the mixed-valence compound of 10(11). This large value also indicates the mixed-valence species is valence-averaged class III and is stabilized by delocalization. The mixed-valence compound has an intense near-infrared band (lambda(max) = 940 nm, epsilon = 27 000 M-1 cm-1). Analysis of this band using Hush's equations for an intervalence transition also indicates the system is delocalized. C1 CALIF POLYTECH STATE UNIV SAN LUIS OBISPO,DEPT PHYS,SAN LUIS OBISPO,CA 93407. MIT,FRANCIS BITTER NATL MAGNET LAB,CAMBRIDGE,MA 02139. UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RP SPREER, LO (reprint author), UNIV PACIFIC,DEPT CHEM,STOCKTON,CA 95211, USA. NR 13 TC 25 Z9 25 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD APR 27 PY 1994 VL 33 IS 9 BP 1753 EP 1755 DI 10.1021/ic00087a006 PG 3 WC Chemistry, Inorganic & Nuclear SC Chemistry GA NJ344 UT WOS:A1994NJ34400006 ER PT J AU HILSENBECK, SJ YOUNG, VG MCCARLEY, RE AF HILSENBECK, SJ YOUNG, VG MCCARLEY, RE TI SYNTHESIS, STRUCTURE, AND CHARACTERIZATION OF N-LIGATED MO6S8L6 CLUSTER COMPLEXES - MOLECULAR PRECURSORS TO CHEVREL PHASES SO INORGANIC CHEMISTRY LA English DT Article ID MOLYBDENUM SULFIDES; SPECTRA; HYDRODESULFURIZATION AB A modified method has been developed for the synthesis of the Mo6S8 Cluster unit in one step from Mo6Cl12 via reaction with NaSH and NaOBu in refluxing n-BuOH-pyridine. The ligand-deficient Na2xMo6S8+x(py)y (1) serves as a convenient starting material for the preparation of the amine complexes Mo6S8L6, with L = pyridine (2), pyrrolidine (4), and piperidine (5). Although propylamine readily dissolves the ligand-deficient starting material, only amorphous Mo6S8(PrNH2)6-x (3) could be isolated. However, the latter acts as a facile reactant for the preparation of the other complexes by ligand substitution. Crystallographic data for the complexes are as follows: Mo6S8(py)6.2py (2), cubic, Pa3BAR, a = 16.994(2) angstrom, Z = 4, R = 0.0381, R(w) = 0.0351; Mo6S8(pyrr)6.pyrr (4), tetragonal, I4(1)/a, a = 29.933(4) angstrom, c = 23.697(8) angstrom, Z = 16, R = 0.0675, wR2 = 0.2034; Mo6S8(pip)6.7pip, (5), tetragonal, I4BAR, a = 19.421(2) angstrom, c = 22.584 (3) angstrom, Z = 8, R = 0.0317, R(w) = 0.0366. These complexes all show strong bands in the IR at 380 +/- 5 cm-1 and in the Raman at 414 +/- 4 cm-1, assigned as predominantly Mo-S stretching modes. XP spectra give characteristic binding energies at 227.7 +/- 0.1 (Mo 3d5/2), 230.8 +/- 0.1 (Mo 3d3/2), 225.1 +/- 0.3 (S 2s), 160.6 +/- 0.1 (S 2p3/2), and 161.8 +/- 0.1 (S 2p1/2) eV. Mo-Mo and Mo-S bond distances show little variation among the complexes, with average values of 2.647 and 2.454 angstrom, respectively. The average Mo-N bond distance, 2.297 angstrom, indicates rather weak bonding of these N-donor ligands. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,MOLEC STRUCT LAB,AMES,IA 50011. NR 29 TC 67 Z9 67 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD APR 27 PY 1994 VL 33 IS 9 BP 1822 EP 1832 DI 10.1021/ic00087a017 PG 11 WC Chemistry, Inorganic & Nuclear SC Chemistry GA NJ344 UT WOS:A1994NJ34400017 ER PT J AU LIANG, W LATIMER, MJ DAU, H ROELOFS, TA YACHANDRA, VK SAUER, K KLEIN, MP AF LIANG, W LATIMER, MJ DAU, H ROELOFS, TA YACHANDRA, VK SAUER, K KLEIN, MP TI CORRELATION BETWEEN STRUCTURE AND MAGNETIC SPIN-STATE OF THE MANGANESE CLUSTER IN THE OXYGEN-EVOLVING COMPLEX OF PHOTOSYSTEM-II IN THE S-2 STATE - DETERMINATION BY X-RAY-ABSORPTION SPECTROSCOPY SO BIOCHEMISTRY LA English DT Article ID ELECTRON-PARAMAGNETIC-RES; PHOTOSYNTHETIC APPARATUS; O2-EVOLVING COMPLEX; FINE-STRUCTURE; O2 EVOLUTION; EPR; RESONANCE; ENZYME; MEMBRANES; SITE AB The structure of the manganese cluster in the S-2 state with the g approximate to 4 EPR signal (S-2.g4 state) generated by 130 K illumination of photosystem II (PSII) membranes prepared from spinach has been investigated by X-ray absorption spectroscopy. The Mn X-ray absorption K-edge spectra of the S-2-g4 state not only show a shift of the inflection point to higher energy from the S-1 state but also reveal a different edge shape from that of the S-2 state with the multiline signal (S-2-MLS state). Extended X-ray absorption fine structure (EXAFS) studies of the Mn K-edge show that the structure of the Mn cluster in the S-2-g4 state is distinctly different from those in the S-2-MLS or S-1 states. In the S-2-g4 state, the second shell of back-scatterers from the Mn absorber is found to contain two Mn-Mn distances of 2.73 and 2.85 Angstrom. We interpret this to indicate the presence of two nonequivalent di-mu-oxo-bridged Mn binuclear structures in the Mn cluster of the S-2-g4 state. The third shell of the S-2-g4 state at about 3.3 Angstrom also contains increased heterogeneity. By contrast, very little distance disorder was found to exist in the second shell of the S-1 or S-2-MLS states. A mechanism is proposed to explain these results in the context of our model for the Mn cluster and the EPR properties of the Mn complex in the S-2 state. C1 UNIV CALIF BERKELEY, LAWRENCE BERKELEY LAB, DIV STRUCT BIOL, BERKELEY, CA 94720 USA. UNIV CALIF BERKELEY, LAWRENCE BERKELEY LAB, DEPT CHEM, BERKELEY, CA 94720 USA. NR 46 TC 55 Z9 55 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD APR 26 PY 1994 VL 33 IS 16 BP 4923 EP 4932 DI 10.1021/bi00182a022 PG 10 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA NH633 UT WOS:A1994NH63300022 PM 8161553 ER PT J AU CHENG, XD ZHANG, X PFLUGRATH, JW STUDIER, FW AF CHENG, XD ZHANG, X PFLUGRATH, JW STUDIER, FW TI THE STRUCTURE OF BACTERIOPHAGE-T7 LYSOZYME, A ZINC AMIDASE AND AN INHIBITOR OF T7 RNA-POLYMERASE SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID TRANSCRIPTION; DETECTOR AB The lysozyme of bacteriophage T7 is a bifunctional protein that cuts amide bonds in the bacterial cell wall and binds to and inhibits transcription by T7 RNA polymerase. The structure of a mutant T7 lysozyme has been determined by x-ray crystallography and refined at 2.2-Angstrom resolution. The protein folds into an alpha/beta-sheet structure that has a prominent cleft. A zinc atom is located in the cleft, bound directly to three amino acids and, through a water molecule, to a fourth. Zinc is required for amidase activity but not for inhibition of T7 RNA polymerase. Alignment of the zinc ligands of T7 lysozyme with those of carboxypeptidase A and thermolysin suggests structural similarity among the catalytic sites for the amidase and these zinc proteases. Mutational analysis identified presumed catalytic residues for amidase activity within the cleft and a surface that appears to be the site of binding to T7 RNA polymerase. Binding of T7 RNA polymerase inhibits amidase activity. C1 BROOKHAVEN NATL LAB,DEPT BIOL,UPTON,NY 11973. RP CHENG, XD (reprint author), COLD SPRING HARBOR LAB,WM KECK STRUCT BIOL LAB,COLD SPRING HARBOR,NY 11724, USA. FU NIGMS NIH HHS [GM21872] NR 22 TC 143 Z9 148 U1 2 U2 12 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD APR 26 PY 1994 VL 91 IS 9 BP 4034 EP 4038 DI 10.1073/pnas.91.9.4034 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA NJ034 UT WOS:A1994NJ03400116 PM 8171031 ER PT J AU FEMEC, DA MCCAFFREY, RR AF FEMEC, DA MCCAFFREY, RR TI SOLVENT REPLACEMENT IN THE SYNTHESIS OF PERSUBSTITUTED PHOSPHONITRILIC HYDROQUINONE PREPOLYMER MATERIALS SO JOURNAL OF APPLIED POLYMER SCIENCE LA English DT Article ID CR IONS; MN IONS; MEMBRANES; SEPARATION; CO AB A desirable solvent replacement has been effected in the synthesis of persubstituted phosphonitrilic hydroquinone prepolymer materials. The replacement of carbon tetrachloride with cyclohexane has no adverse effect on the composition and quality of the material prepared. The overall yield of the reaction increases from 65 to 70% and the toxicity of the reaction mixture and of the waste generated from the reaction are greatly reduced. The particularly close match of solvent properties between carbon tetrachloride and cyclohexane makes this an excellent solvent replacement. Such changes to less-expensive, less-toxic, and less-environmentally damaging solvents are on the increase. A brief list of some known replacement solvents for use in polymer and coatings applications is presented. (C) 1994 John Wiley & Sons, Inc. RP FEMEC, DA (reprint author), EG&G IDAHO INC,DEPT SCI & TECHNOL,CHEM SCI GRP,POB 1625,IDAHO FALLS,ID 83415, USA. NR 12 TC 12 Z9 12 U1 0 U2 0 PU JOHN WILEY & SONS INC PI NEW YORK PA 605 THIRD AVE, NEW YORK, NY 10158-0012 SN 0021-8995 J9 J APPL POLYM SCI JI J. Appl. Polym. Sci. PD APR 25 PY 1994 VL 52 IS 4 BP 501 EP 505 DI 10.1002/app.1994.070520404 PG 5 WC Polymer Science SC Polymer Science GA NB986 UT WOS:A1994NB98600004 ER PT J AU LUO, WF FELDBERG, SW RUDOLPH, M AF LUO, WF FELDBERG, SW RUDOLPH, M TI ENSURING SELF-CONSISTENT ASSIGNMENT OF THERMODYNAMIC PARAMETERS IN SIMULATIONS OF ELECTROCHEMICAL CHEMICAL-SYSTEMS SO JOURNAL OF ELECTROANALYTICAL CHEMISTRY LA English DT Article ID CYCLIC VOLTAMMETRY; ECE MECHANISM; ALGORITHM; NUANCES AB A general method for ensuring the self-consistent assignment of thermodynamic parameters in simulations of electrochemical-chemical systems is described. An essential part of the method is the identification of thermodynamically superfluous reactions (TSRs) which are defined as reactions in which the value of K(m) or E(m)o is a function of one or more previously specified values of K(m) or E(m)o for other reactions. A TSR can be removed from the system without altering the final equilibrium distribution of concentrations. However, a TSR can modify the time-dependent behavior of the system significantly. By identifying a TSR, assignment of an athermodynamic value for its equilibrium constant or formal potential can be precluded. The value of the equilibrium constant K(m) or formal potential E(m)o associated with any given TSR can be computed. This approach, which is designed to function in a cyclic voltammetric simulator which can generate and solve the requisite kinetic equations for any user-specified mechanism, is also generally applicable to any chemical or electrochemical simulation. C1 FRIEDRICH SCHILLER UNIV,FAK CHEM,INST ANORGAN & ANALYT CHEM,O-6900 JENA,GERMANY. RP LUO, WF (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,DIV CHEM SCI,UPTON,NY 11973, USA. NR 11 TC 29 Z9 29 U1 0 U2 1 PU ELSEVIER SCIENCE SA LAUSANNE PI LAUSANNE 1 PA PO BOX 564, 1001 LAUSANNE 1, SWITZERLAND SN 0022-0728 J9 J ELECTROANAL CHEM JI J. Electroanal. Chem. PD APR 25 PY 1994 VL 368 IS 1-2 BP 109 EP 113 DI 10.1016/0022-0728(93)03083-2 PG 5 WC Chemistry, Analytical; Electrochemistry SC Chemistry; Electrochemistry GA NK414 UT WOS:A1994NK41400012 ER PT J AU WANG, CZ HO, KM AF WANG, CZ HO, KM TI THE ELECTRONIC-STRUCTURE OF DIAMOND-LIKE AMORPHOUS-CARBON SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter ID FILMS AB The electronic structure of diamond-like amorphous carbon is investigated using a tight-binding molecular dynamics method. The study shows that bonding and antibonding of pi-states associated with pairs and quartets of threefold 'defected atoms' embedded in the fourfold matrix yield a band gap of about 2 eV as observed in optical absorption experiments. These states are in general very localized. However, coupling between the threefold 'defects' can produce delocalized states near the band gap, which is essential for electronic conductivity in the material. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. RP WANG, CZ (reprint author), IOWA STATE UNIV SCI & TECHNOL,AMES LAB,AMES,IA 50011, USA. NR 19 TC 18 Z9 18 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TECHNO HOUSE, REDCLIFFE WAY, BRISTOL, ENGLAND BS1 6NX SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD APR 25 PY 1994 VL 6 IS 17 BP L239 EP L244 DI 10.1088/0953-8984/6/17/002 PG 6 WC Physics, Condensed Matter SC Physics GA NH957 UT WOS:A1994NH95700002 ER PT J AU CHEUNG, YW STEIN, RS LIN, JS WIGNALL, GD AF CHEUNG, YW STEIN, RS LIN, JS WIGNALL, GD TI SMALL-ANGLE SCATTERING INVESTIGATIONS OF POLY(EPSILON-CAPROLACTONE) POLYCARBONATE BLENDS .2. SMALL-ANGLE X-RAY AND LIGHT-SCATTERING STUDY OF SEMICRYSTALLINE SEMICRYSTALLINE AND SEMICRYSTALLINE AMORPHOUS BLEND MORPHOLOGIES SO MACROMOLECULES LA English DT Article ID POLYETHYLENE; POLYMERS; NEUTRON AB Crystalline morphologies of poly(epsilon-caprolactone) (PCL) and polycarbonate (PC) blends were probed with small-angle X-ray scattering (SAXS) and small-angle light scattering (SALS). Quantitative SAXS analysis suggested that random mixing of PCL and PC lamellae occurred in the semicrystalline/semicrystalline state. Two distinct regions of incorporation were identified in the semicrystalline/amorphous state. It was found that PCL was rejected from the PC interlamellar region in the PCL-rich blends. In contrast, PCL was incorporated into the amorphous phase between the crystalline lamellae in the PC-rich blends. This transition from interlamellar exclusion to interlamellar inclusion may be related to the glass transition temperatures or the mobility of the blends. It is proposed that the mode of incorporation or exclusion is governed by the competition between entropy and diffusion. Additionally, SALS coupled with optical microscopy indicated that PC is an effective nucleating agent for PCL crystallization as manifested by the reduction of PCL spherulitic size with the addition of PC. C1 UNIV MASSACHUSETTS, DEPT POLYMER SCI & ENGN, AMHERST, MA 01003 USA. OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. OI Wignall, George/0000-0002-3876-3244 NR 34 TC 68 Z9 70 U1 1 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 EI 1520-5835 J9 MACROMOLECULES JI Macromolecules PD APR 25 PY 1994 VL 27 IS 9 BP 2520 EP 2528 DI 10.1021/ma00087a021 PG 9 WC Polymer Science SC Polymer Science GA NJ226 UT WOS:A1994NJ22600021 ER PT J AU CODY, GD BOTTO, RE AF CODY, GD BOTTO, RE TI IN-SITU ANALYSIS AND QUANTIFICATION OF SWELLING KINETICS IN GLASSY AND RUBBERY NETWORKS USING H-1 AND F-19 MAGNETIC-RESONANCE MICROSCOPIES SO MACROMOLECULES LA English DT Article ID CASE-II DIFFUSION; POLYMER-SOLVENT SYSTEMS; MACROMOLECULAR STRUCTURE; ANOMALOUS DIFFUSION; SOLID POLYMERS; SORPTION; COAL; GELS; THERMODYNAMICS; TEMPERATURE AB H-1 and F-19 magnetic resonance microscopies are used to determine the characteristics of diffusion in four different network-solvent systems. Time-resolved analysis of the concentration profiles of toluene in polybutadiene and hexafluorobenzene in poly(methyl silicone) demonstrates that solvent transport in these systems is Fickian. The kinetics of solvent transport in two glassy networks, however, is shown to be non-Fickian. These latter two systems are characterized by sharp solvent fronts which propagate into the cores of the samples at a constant velocity. The swelling kinetics are quantified by applying a simple model which couples the kinetics of solvent diffusion to a second-order phase transition which induces network relaxation. Parameterization is accomplished with two kinetic terms and one thermodynamic parameter. These are a mass-fixed glassy diffusion coefficient, a network relaxation constant, and a critical concentration corresponding to the concentration of solvent necessary to induce a glass to rubber transition. Solvent from velocities, obtained through magnetic resonance microscopy, are used with independently derived critical concentrations to calculate the glassy diffusion coefficient and network relaxation rate constant. Kinetic swelling data are then fit with theoretical uptake curves computed using these parameters. A high-quality fit demonstrates that the proposed model successfully quantifies non-Fickian transport using a small number of physically based dynamic parameters. RP CODY, GD (reprint author), ARGONNE NATL LAB,DIV CHEM,9700 S CASS AVE,ARGONNE,IL 60439, USA. NR 42 TC 26 Z9 27 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD APR 25 PY 1994 VL 27 IS 9 BP 2607 EP 2614 DI 10.1021/ma00087a033 PG 8 WC Polymer Science SC Polymer Science GA NJ226 UT WOS:A1994NJ22600033 ER PT J AU LOPEZ, JA RANDRUP, J AF LOPEZ, JA RANDRUP, J TI THEORY OF NUCLEAR MULTIFRAGMENTATION .3. PRETRANSITION NUCLEON RADIATION SO NUCLEAR PHYSICS A LA English DT Article ID MOMENTA AB Within the framework of a previously developed transition-state theory for nuclear multifragmentation, we study the effect of pre-transition radiation of nucleons on the partial widths for breakup into specified multifragment channels. Typically, a considerable portion of the mass and energy of the source is radiated during the evolution of the system from a spherical compound nucleus towards the conditional saddle configuration, thus causing a significant reduction of the multifragmentation width. C1 LAWRENCE BERKELEY LAB,DIV NUCL SCI,BERKELEY,CA 94720. RP LOPEZ, JA (reprint author), UNIV TEXAS,DEPT PHYS,EL PASO,TX 79968, USA. NR 11 TC 12 Z9 12 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9474 J9 NUCL PHYS A JI Nucl. Phys. A PD APR 25 PY 1994 VL 571 IS 2 BP 379 EP 392 DI 10.1016/0375-9474(94)90066-3 PG 14 WC Physics, Nuclear SC Physics GA NG977 UT WOS:A1994NG97700009 ER PT J AU BURWICK, TT AF BURWICK, TT TI ALL-ORDER QUANTUM-GRAVITY IN 2 DIMENSIONS SO NUCLEAR PHYSICS B LA English DT Article ID HIGHER-DERIVATIVE GRAVITY; PLANAR RANDOM SURFACES; LIOUVILLE THEORY; ARBITRARY DIMENSIONS; FIELD-THEORY; 2-DIMENSIONAL GRAVITY; NONCRITICAL STRINGS; BACKGROUND FIELDS; VERTEX OPERATORS; QUANTIZATION AB We derive curvature counterterms in two-dimensional gravity coupled to conformal matter up to infinite order. By construction the higher-order action is equivalent to a finite first-order theory with an auxiliary scalar. Due to this equivalence it shares the following remarkable properties: There is no need for gravitational dressing of the cosmological constant, quantization is consistent for any conformal anomaly c of the coupled matter system, and if the coupled matter system is a (c = d)-dimensional string theory in a euclidean background then the effective string theory is (D = d + 2)-dimensional with Minkowski signature (1, D - 1). The resulting quantum theory favours flat geometries and suppresses both parabolic and hyperbolic singularities. RP BURWICK, TT (reprint author), STANFORD UNIV,STANFORD LINEAR ACCELERATOR CTR,STANFORD,CA 94309, USA. NR 70 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD APR 25 PY 1994 VL 418 IS 1-2 BP 257 EP 277 DI 10.1016/0550-3213(94)90247-X PG 21 WC Physics, Particles & Fields SC Physics GA NN122 UT WOS:A1994NN12200013 ER PT J AU ALTSCHULER, EL WILLIAMS, TJ RATNER, ER DOWLA, F WOOTEN, F AF ALTSCHULER, EL WILLIAMS, TJ RATNER, ER DOWLA, F WOOTEN, F TI METHOD OF CONSTRAINED GLOBAL OPTIMIZATION SO PHYSICAL REVIEW LETTERS LA English DT Article ID POINT CHARGES; SPHERE; CONFIGURATIONS AB We present a new method for optimization: constrained global optimization (CGO). CGO iteratively uses a Glauber spin flip probability and the Metropolis algorithm. The spin flip probability allows changing only the values of variables contributing excessively to the function to be minimized. We illustrate CGO with two problems-Thomson's problem of finding the minimum-energy configuration of unit charges on a spherical surface, and a problem of assigning offices-for which CGO finds better minima than other methods. We think CGO will apply to a wide class of optimization problems. C1 UNIV CALIF DAVIS LIVERMORE,DEPT APPL SCI,LIVERMORE,CA 94551. STANFORD UNIV,DEPT APPL PHYS,STANFORD,CA 94305. RP ALTSCHULER, EL (reprint author), LAWRENCE LIVERMORE NATL LAB,POB 808,LIVERMORE,CA 94550, USA. NR 13 TC 66 Z9 68 U1 1 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 25 PY 1994 VL 72 IS 17 BP 2671 EP 2674 DI 10.1103/PhysRevLett.72.2671 PG 4 WC Physics, Multidisciplinary SC Physics GA NH254 UT WOS:A1994NH25400001 ER PT J AU LIU, JM DEGROOT, JS MATTE, JP JOHNSTON, TW DRAKE, RP AF LIU, JM DEGROOT, JS MATTE, JP JOHNSTON, TW DRAKE, RP TI MEASUREMENTS OF INVERSE BREMSSTRAHLUNG ABSORPTION AND NON-MAXWELLIAN ELECTRON VELOCITY DISTRIBUTIONS SO PHYSICAL REVIEW LETTERS LA English DT Article ID HEAT-TRANSPORT; PLASMAS AB Non-Maxwellian (flattopped) electron velocity distributions resulting from inverse bremsstrahlung of intense microwaves are measured directly for the first time in experiments performed on the UCD AURORA II device. The experiments are performed in the afterglow of a pulsed discharge plasma that is moderately collisional and sufficiently ionized (approximately 1%) that Coulomb collisions are dominant. Langmuir probe measurements indicate that the isotropic component of the electron velocity distribution is non-Maxwellian in very good agreement with electron kinetic (Fokker-Planck) simulations. C1 INST NATL RECH SCI ENERGIE & MAT,VARENNES J3X 1S2,PQ,CANADA. LAWRENCE LIVERMORE NATL LAB,PLASMA PHYS RES INST,LIVERMORE,CA 94551. RP LIU, JM (reprint author), UNIV CALIF DAVIS,DEPT APPL SCI,PLASMA RES GRP,DAVIS,CA 95616, USA. RI Drake, R Paul/I-9218-2012 OI Drake, R Paul/0000-0002-5450-9844 NR 18 TC 85 Z9 85 U1 1 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 25 PY 1994 VL 72 IS 17 BP 2717 EP 2720 DI 10.1103/PhysRevLett.72.2717 PG 4 WC Physics, Multidisciplinary SC Physics GA NH254 UT WOS:A1994NH25400013 ER PT J AU PASTERNAK, MP TAYLOR, RD KRUGER, MB JEANLOZ, R ITIE, JP POLIAN, A AF PASTERNAK, MP TAYLOR, RD KRUGER, MB JEANLOZ, R ITIE, JP POLIAN, A TI PRESSURE-INDUCED AMORPHIZATION OF GEI4 MOLECULAR-CRYSTALS SO PHYSICAL REVIEW LETTERS LA English DT Article ID ALPHA-QUARTZ; ALPO4; SNI4; SPECTROSCOPY; MOSSBAUER; MEMORY; STATE; PHASE; GLASS AB X-ray, Mossbauer spectroscopy, and extended x-ray absorption fine structure studies provide an atomic-scale description of the pressure-amorphized GeI4. At P > 12 GPa a gradual onset of structural disorder accompanied by a molecular-association process is observed. An amorphized state concurring with the transformation of the molecular crystal into a metallic glass stabilizes at 25 GPa. It is accomplished by a gradual growth of a disordered (GeI4)n polymer, a phase characterized by enhanced Ge-I bond lengths and charge delocalization. Both phenomena are consistent with a I5p --> Ge4s4p charge-transfer band closure. C1 LOS ALAMOS NATL LAB,DIV PHYS,LOS ALAMOS,NM 87545. UNIV CALIF BERKELEY,DEPT GEOL & GEOPHYS,BERKELEY,CA 94720. UNIV PARIS 06,F-75252 PARIS 05,FRANCE. RP PASTERNAK, MP (reprint author), TEL AVIV UNIV,SCH PHYS & ASTRON,IL-69978 TEL AVIV,ISRAEL. RI Polian, Alain/E-1555-2017 OI Polian, Alain/0000-0003-2261-9114 NR 26 TC 29 Z9 29 U1 0 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 25 PY 1994 VL 72 IS 17 BP 2733 EP 2736 DI 10.1103/PhysRevLett.72.2733 PG 4 WC Physics, Multidisciplinary SC Physics GA NH254 UT WOS:A1994NH25400017 ER PT J AU MCKEE, RA WALKER, FJ SPECHT, ED JELLISON, GE BOATNER, LA HARDING, JH AF MCKEE, RA WALKER, FJ SPECHT, ED JELLISON, GE BOATNER, LA HARDING, JH TI INTERFACE STABILITY AND THE GROWTH OF OPTICAL-QUALITY PEROVSKITES ON MGO SO PHYSICAL REVIEW LETTERS LA English DT Article ID THIN-FILMS; EPITAXIAL-GROWTH; SEGREGATION AB An understanding of heteroepitaxy between perovskite and alkaline earth oxides is developed in terms of ion size and interfacial electrostatics. Interfacial energy minimization at the first atomic layers is the basis for a commensurate, unit-cell stability. This unit-cell stability presents the opportunity to study reduced dimensional or two-dimensional phenomena in thin-film ferroelectrics and is the basis for growth of high crystal quality, mum-thick films for optical device applications. C1 UNIV TENNESSEE,KNOXVILLE,TN 37996. HARWELL LAB,AEA IND TECHNOL,DEPT THEORET STUDIES,DIDCOT OX11 0RA,OXON,ENGLAND. RP MCKEE, RA (reprint author), OAK RIDGE NATL LAB,OAK RIDGE,TN 37831, USA. RI Specht, Eliot/A-5654-2009; Boatner, Lynn/I-6428-2013; OI Specht, Eliot/0000-0002-3191-2163; Boatner, Lynn/0000-0002-0235-7594; Walker, Frederick/0000-0002-8094-249X NR 20 TC 113 Z9 114 U1 0 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 25 PY 1994 VL 72 IS 17 BP 2741 EP 2744 DI 10.1103/PhysRevLett.72.2741 PG 4 WC Physics, Multidisciplinary SC Physics GA NH254 UT WOS:A1994NH25400019 ER PT J AU GULACSI, M BEDELL, KS AF GULACSI, M BEDELL, KS TI METAL-INSULATOR-TRANSITION IN 1D HUBBARD-MODEL SO PHYSICAL REVIEW LETTERS LA English DT Article ID CORRELATED ELECTRON-SYSTEMS; CORRELATION EXPONENTS; COMPLEX WAVENUMBERS; QUANTUM FLUIDS; EXCITATIONS; CHAIN; SPECTRUM; STATES AB For the one-dimensional Hubbard model we extended the bosonization technique, away from half filling, in such a way that a general formula is obtained for the zero temperature single-particle Green function with validity over the whole doping range. Our method allows us to calculate, for the first time, the one-body Green function in both Tomonaga-Luttinger and Luther-Emery universality classes, to characterize the crossover between these two behaviors and thus, to describe the metal-insulator transition. We have found that the transition can be characterized as a Brinkman-Rice transition with a diverging effective mass. RP GULACSI, M (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,MS-B262,LOS ALAMOS,NM 87545, USA. NR 33 TC 25 Z9 25 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 25 PY 1994 VL 72 IS 17 BP 2765 EP 2768 DI 10.1103/PhysRevLett.72.2765 PG 4 WC Physics, Multidisciplinary SC Physics GA NH254 UT WOS:A1994NH25400025 ER PT J AU REYNOLDS, WN PEARSON, JE PONCEDAWSON, S AF REYNOLDS, WN PEARSON, JE PONCEDAWSON, S TI DYNAMICS OF SELF-REPLICATING PATTERNS IN REACTION-DIFFUSION SYSTEMS SO PHYSICAL REVIEW LETTERS LA English DT Article AB Recently solutions to a simple reaction diffusion system have been discovered in which localized structures (spots) make copies of themselves. In this Letter we analyze the one-dimensional analog of this process in which replication occurs until the domain is filled with a periodic array of spots. We provide a heuristic explanation of why this replication process should occur in a broad class of systems. Time dependent solutions are developed for model systems and their analytic structures investigated. C1 LOS ALAMOS NATL LAB,CTR NONLINEAR STUDIES,LOS ALAMOS,NM 87545. RP REYNOLDS, WN (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,COMPLEX SYST GRP,LOS ALAMOS,NM 87545, USA. OI Ponce Dawson, Silvina/0000-0001-6550-4267 NR 14 TC 129 Z9 129 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 25 PY 1994 VL 72 IS 17 BP 2797 EP 2800 DI 10.1103/PhysRevLett.72.2797 PG 4 WC Physics, Multidisciplinary SC Physics GA NH254 UT WOS:A1994NH25400033 ER PT J AU KRAUS, GA LI, J GORDON, M JENSEN, JH AF KRAUS, GA LI, J GORDON, M JENSEN, JH TI REGIOCONTROL BY REMOTE SUBSTITUENTS - A DIRECT TOTAL SYNTHESIS OF RACEMIC HONGCONIN SO JOURNAL OF ORGANIC CHEMISTRY LA English DT Article ID DIELS-ALDER REACTIONS; AKLAVINONE AB The total synthesis of hongconin (1) has been completed. Key steps include the metalation of a benzylic alcohol, the formation of a six-membered ring ether via a mercury-mediated cyclization, and the regioselective installation of the naphthalene ring by way of a Diels-Alder reaction. C1 US DOE,AMES LAB,AMES,IA 50011. US DOE,DEPT CHEM,AMES,IA 50011. RP KRAUS, GA (reprint author), IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011, USA. RI Jensen, Jan/G-4338-2010 OI Jensen, Jan/0000-0002-1465-1010 NR 18 TC 26 Z9 26 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3263 J9 J ORG CHEM JI J. Org. Chem. PD APR 22 PY 1994 VL 59 IS 8 BP 2219 EP 2222 DI 10.1021/jo00087a044 PG 4 WC Chemistry, Organic SC Chemistry GA NJ137 UT WOS:A1994NJ13700044 ER PT J AU TARTER, CB AF TARTER, CB TI LIVERMORE LAB HEAD SO SCIENCE LA English DT Letter RP TARTER, CB (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD APR 22 PY 1994 VL 264 IS 5158 BP 489 EP 489 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA NH010 UT WOS:A1994NH01000002 ER PT J AU HULET, EK AF HULET, EK TI ELEMENT NAMING SO SCIENCE LA English DT Letter RP HULET, EK (reprint author), LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550, USA. NR 5 TC 1 Z9 1 U1 0 U2 0 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 SN 0036-8075 J9 SCIENCE JI Science PD APR 22 PY 1994 VL 264 IS 5158 BP 491 EP 491 DI 10.1126/science.264.5158.491 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA NH010 UT WOS:A1994NH01000009 PM 17732720 ER PT J AU SCOTT, CD WOODWARD, CA SCOTT, TC AF SCOTT, CD WOODWARD, CA SCOTT, TC TI USE OF CHEMICALLY-MODIFIED ENZYMES IN ORGANIC-SOLVENTS FOR CONVERSION OF COAL TO LIQUIDS SO CATALYSIS TODAY LA English DT Article ID SOLUBILIZATION AB Reductive enzymes can be used to enhance the conversion of coal to liquids. This can be carried out in both aqueous and organic media, but, in the latter case, the enzymes must be chemically modified so that they are soluble and active in the organic environment. The most effective chemical modification of enzymes is achieved by using reagents such as activated polyethylene glycol or dinitrofluorobenzene that add hydrophobic groups. Use of such modified enzymes in organic solvents such as benzene or pyridine has resulted in the conversion of over 40% of bituminous coal. RP SCOTT, CD (reprint author), OAK RIDGE NATL LAB,CTR BIOPROC RES & DEV,POB 2008,OAK RIDGE,TN 37831, USA. NR 23 TC 7 Z9 8 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 J9 CATAL TODAY JI Catal. Today PD APR 21 PY 1994 VL 19 IS 3 BP 381 EP 393 DI 10.1016/0920-5861(94)87005-5 PG 13 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA NJ109 UT WOS:A1994NJ10900005 ER PT J AU CUGINI, AV KRASTMAN, D LETT, RG BALSONE, VD AF CUGINI, AV KRASTMAN, D LETT, RG BALSONE, VD TI DEVELOPMENT OF A DISPERSED IRON CATALYST FOR 1ST STAGE COAL-LIQUEFACTION SO CATALYSIS TODAY LA English DT Article AB A procedure yielding a very small particle size iron catalyst for coal liquefaction has been developed at the Pittsburgh Energy Technology Center. This procedure has two important components. The first is incipient wetness impregnation of coal with an aqueous solution of ferric nitrate (subsequently converted to hydrated iron oxide by contact with ammonium hydroxide). The second is proper time/temperature activation of the iron under a gaseous atmosphere of H-2/H2S to produce pyrrholite. In continuous operations. an optimum preliquefaction temperature of 275-degrees-C was observed for the activation of hydrated iron oxide in the presence of Illinois No. 6 coal. The net effect of proper implementation of this procedure was the development of a finely divided iron catalyst that exhibited high levels of activity in comparisons with molybdenum catalysts. C1 GILBERT COMMONWEALTH INC, LIB, PITTSBURGH, PA 15129 USA. RP US DOE, PITTSBURGH ENERGY TECHNOL CTR, POB 10940, PITTSBURGH, PA 15236 USA. NR 19 TC 17 Z9 20 U1 2 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5861 EI 1873-4308 J9 CATAL TODAY JI Catal. Today PD APR 21 PY 1994 VL 19 IS 3 BP 395 EP 407 DI 10.1016/0920-5861(94)87006-3 PG 13 WC Chemistry, Applied; Chemistry, Physical; Engineering, Chemical SC Chemistry; Engineering GA NJ109 UT WOS:A1994NJ10900006 ER PT J AU JIN, CM HETTICH, R COMPTON, R JOYCE, D BLENCOE, J BURCH, T AF JIN, CM HETTICH, R COMPTON, R JOYCE, D BLENCOE, J BURCH, T TI DIRECT SOLID-PHASE HYDROGENATION OF FULLERENES SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Letter ID C-60; CARBON; BUCKMINSTERFULLERENE; IONIZATION AB Direct hydrogenation of C-60 and C-70 was achieved without the use of a catalyst by exposing solid-phase fullerenes to high-pressure hydrogen gas (500-850 bar) at temperatures ranging from 573 to 623 K. Efficient production of C60Hx (X = 2-18) and C70Hy (y = 4-30) was identified by laser desorption Fourier transform mass spectrometry. Temperatures above 950 K in the presence of H-2 resulted in complete degradation of the fullerene samples. Gas-phase studies of the C60Hx+ ions revealed that these species will undergo proton transfer to pyridine, indicating that at least some of the hydrogens are bound exohedral to the fullerene cage and that the C60Hx species have lower ionization potentials than C-60 itself. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RI Hettich, Robert/N-1458-2016 OI Hettich, Robert/0000-0001-7708-786X NR 21 TC 84 Z9 87 U1 1 U2 7 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 21 PY 1994 VL 98 IS 16 BP 4215 EP 4217 DI 10.1021/j100067a004 PG 3 WC Chemistry, Physical SC Chemistry GA NH490 UT WOS:A1994NH49000004 ER PT J AU LONG, MA KALER, EW LEE, SP WIGNALL, GD AF LONG, MA KALER, EW LEE, SP WIGNALL, GD TI CHARACTERIZATION OF LECITHIN-TAURODEOXYCHOLATE MIXED MICELLES USING SMALL-ANGLE NEUTRON-SCATTERING AND STATIC AND DYNAMIC LIGHT-SCATTERING SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID NUCLEAR MAGNETIC-RESONANCE; BILIARY LIPID SYSTEMS; BILE-SALT MICELLES; CHOLESTEROL SOLUBILIZATION; CONCENTRATION FLUCTUATION; SEMIDILUTE REGIMES; POLYMER SYSTEMS; ISOTROPIC-PHASE; STIFF POLYMERS; MODEL BILE AB We have used small-angle neutron scattering (SANS) to probe the structure and interparticle interactions of lecithin-taurodeoxycholate mixed micelles. The data are fit to a core-shell model that provides the micelle composition and dimensions. The effects on the scattering spectra of electrostatic and excluded-volume interactions are explored in terms of the decoupling approximation (Kotlarchyk, M.; Chen, S.-H. J. Chem. Phys. 1983, 79, 2461) and the random phase approximation (Shimada, T.; Doi, M.; Okano, K. J. Chem. Phys. 1988, 88, 2815). We found the TDC-lecithin micelles are cylindrical particles with an average cross-sectional radius of 26.7 +/- 0.4 Angstrom. The core-shell structure is found to be an appropriate model for the highly hydrated micelles. The micelle length increases dramatically with an increase in added electrolyte, but not with decreasing concentration as previously reported. The SANS data analysis shows that particles in 0.05 M NaCl grow by less than 15% with a 3-fold decrease in the total surfactant concentration. This is in contrast to the simple interpretation of dynamic light scattering of the same samples that shows an apparent doubling of the micelle length with the same decrease in surfactant concentration. This discrepancy is attributed to neglect of the thermodynamic and hydrodynamic interactions in the analysis of the dynamic light scattering data. Corrections for the thermodynamic interactions are determined from the static data and applied to the interpretation of dynamic light scattering measurements. The strength of hydrodynamic and entanglement interactions is also discussed in relation to existing models for both semidilute polymer solutions and spherical particles. C1 UNIV DELAWARE,CTR MOLEC & ENGN THERMODYNAM,DEPT CHEM ENGN,NEWARK,DE 19716. VET ADM MED CTR,SEATTLE,WA 98108. OAK RIDGE NATL LAB,DIV SOLID STATE,OAK RIDGE,TN 37830. RI Lee, Sum Ping/C-4333-2009; OI Wignall, George/0000-0002-3876-3244 NR 59 TC 44 Z9 44 U1 1 U2 12 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 21 PY 1994 VL 98 IS 16 BP 4402 EP 4410 DI 10.1021/j100067a031 PG 9 WC Chemistry, Physical SC Chemistry GA NH490 UT WOS:A1994NH49000031 ER PT J AU ANCHELL, JL WHITE, JC THOMPSON, MR HESS, AC AF ANCHELL, JL WHITE, JC THOMPSON, MR HESS, AC TI AN AB-INITIO PERIODIC HARTREE-FOCK STUDY OF GROUP IA CATIONS IN ANA-TYPE ZEOLITES SO JOURNAL OF PHYSICAL CHEMISTRY LA English DT Article ID MOLECULAR-ORBITAL METHODS; VALENCE BASIS-SETS; POLLUCITE STRUCTURE; CESIUM; IMMOBILIZATION; STRONTIUM; ELEMENTS AB This study investigates the electronic structure of Group IA cations intercalated into zeolites with the analcime (ANA) framework using ab initio periodic Hartree-Fock theory. The purpose of the study is to gain a better understanding of the role played by electron-donating species in zeolites in general, with specific applications to materials that have been suggested as storage matrices for radioactive materials. The effect of the intercalated species (Na, K, Rb, and Cs) on the electronic structure of the zeolite is presented on the basis of an analysis of the total and projected density of states, Mulliken charges, and charge density differences. The results of those analyses indicate that, relative to a charge neutral atomic state, the Group IA species donate an electron to the zeolite lattice and interact most strongly with the s and p atomic states of oxygen as the species are moved through the lattice. In addition, estimates of the self-diffusion constants of Na, K, Rb, and Cs based upon a one-dimensional diffusion model parameterized from the ab initio total energy data will be presented. We find that the estimated self-diffusion rate decreased markedly with increasing cation size, and that the diffusion rate of Cs was essentially zero in bulk pollucite. The cationic charge is unchanged as the species moves through the lattice. This indicates that model potentials based upon an ionic interpretation of the Group IA species may be reasonable. C1 PACIFIC NW LAB, RICHLAND, WA 99352 USA. NR 23 TC 16 Z9 17 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0022-3654 J9 J PHYS CHEM-US JI J. Phys. Chem. PD APR 21 PY 1994 VL 98 IS 16 BP 4463 EP 4468 DI 10.1021/j100067a038 PG 6 WC Chemistry, Physical SC Chemistry GA NH490 UT WOS:A1994NH49000038 ER PT J AU GINGRICH, D GREENIOUS, G KITCHING, P OLSEN, B PINFOLD, J RODNING, N BOOS, E SCHAOUTNIKOV, BO AUBERT, B BAZAN, A BEAUGIRAUD, B COLAS, J LEFLOUR, T MARIE, M STIPCEVIC, M WINGERTERSEEZ, I ZOLNIEROWSKI, YP CHEMEISSIANI, M FERNANDEZ, E GARRIDO, L MARTINEZ, M PADILLA, C GORDON, HA RADEKA, V RAHM, D STEPHANI, D CHEVALLEY, JL FABJAN, CW GILDEMEISTER, O JENNI, P NESSI, M POGGIOLI, L RICHTEL, W VUILLEMIN, V BAZE, JM GOSSET, L LAVOCAT, P LOTTIN, JP MANSOULIE, B MEYER, JP RENARDY, JF SCHWINDLING, J TEIGER, J ZACCONE, H COLLOT, J DESAINTIGNON, P DZAHINI, D LABORIE, G MAHOUT, G MERCHEZ, E POUXE, J BATTISTONI, G CAMIN, DV CAVALLI, D COSTA, G COZZI, L CRAVERO, A FERRARI, A GIANOTTI, F MANDELLI, L MANFREDI, F MAZZANTI, M PERINI, L RE, V SALA, P SPEZIALI, V BARREIRO, F HERVAS, L LABARGA, L BASA, S CHECKTMAN, A CLEMENS, JC COUSINOU, MC DARGENT, P ETIENNE, F FOUCHEZ, D MONNIER, E NACASH, R NAGY, E OLIVETTO, C SAUVAGE, D TISSERANT, S AZUELOS, G BEAUDOIN, G DEPOMMIER, P FLORIAN, EI LEROY, C ROY, J AUGE, E CHASE, R CHOLLET, JC DELATAILLE, C FAYARD, L FOURNIER, D HIROSOHO, A JEAN, P ICONOMIDOUFAYARD, L MERKEL, B NOPPE, JM PARROUR, G PETROFF, P REPELLIN, JP SCHAFFER, A SEGUIN, N SERIN, L UNAL, G CANTON, D HANSLKOZANECKA, G IMBAULT, D LORY, J ZITOUN, R EEK, LO LUNDJENSEN, B SODERQVIST, J ASTBURY, A GAIDOS, G KEELER, R LEFEBVRE, M WHITE, J AF GINGRICH, D GREENIOUS, G KITCHING, P OLSEN, B PINFOLD, J RODNING, N BOOS, E SCHAOUTNIKOV, BO AUBERT, B BAZAN, A BEAUGIRAUD, B COLAS, J LEFLOUR, T MARIE, M STIPCEVIC, M WINGERTERSEEZ, I ZOLNIEROWSKI, YP CHEMEISSIANI, M FERNANDEZ, E GARRIDO, L MARTINEZ, M PADILLA, C GORDON, HA RADEKA, V RAHM, D STEPHANI, D CHEVALLEY, JL FABJAN, CW GILDEMEISTER, O JENNI, P NESSI, M POGGIOLI, L RICHTEL, W VUILLEMIN, V BAZE, JM GOSSET, L LAVOCAT, P LOTTIN, JP MANSOULIE, B MEYER, JP RENARDY, JF SCHWINDLING, J TEIGER, J ZACCONE, H COLLOT, J DESAINTIGNON, P DZAHINI, D LABORIE, G MAHOUT, G MERCHEZ, E POUXE, J BATTISTONI, G CAMIN, DV CAVALLI, D COSTA, G COZZI, L CRAVERO, A FERRARI, A GIANOTTI, F MANDELLI, L MANFREDI, F MAZZANTI, M PERINI, L RE, V SALA, P SPEZIALI, V BARREIRO, F HERVAS, L LABARGA, L BASA, S CHECKTMAN, A CLEMENS, JC COUSINOU, MC DARGENT, P ETIENNE, F FOUCHEZ, D MONNIER, E NACASH, R NAGY, E OLIVETTO, C SAUVAGE, D TISSERANT, S AZUELOS, G BEAUDOIN, G DEPOMMIER, P FLORIAN, EI LEROY, C ROY, J AUGE, E CHASE, R CHOLLET, JC DELATAILLE, C FAYARD, L FOURNIER, D HIROSOHO, A JEAN, P ICONOMIDOUFAYARD, L MERKEL, B NOPPE, JM PARROUR, G PETROFF, P REPELLIN, JP SCHAFFER, A SEGUIN, N SERIN, L UNAL, G CANTON, D HANSLKOZANECKA, G IMBAULT, D LORY, J ZITOUN, R EEK, LO LUNDJENSEN, B SODERQVIST, J ASTBURY, A GAIDOS, G KEELER, R LEFEBVRE, M WHITE, J TI PERFORMANCE OF THE LIQUID ARGON ELECTROMAGNETIC AND HADRONIC ACCORDION CALORIMETER FOR THE LHC SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article; Proceedings Paper CT 5th Topical Seminar on Experimental Apparatus for High Energy Particle Physics and Astrophysics CY APR 26-30, 1993 CL SAN MINIATO, ITALY SP ITALIAN INST NUCL PHYS, UNIV BOLOGNA, UNIV FLORENCE, REG TOSCANA, CASSA RISPARMIO SAN MINIATO AB A large scale prototype of a liquid argon accordion calorimeter, conceived as a sector of a full LHC Barrel detector and consisting of an electromagnetic and a hadronic section, has been constructed and tested at the CERN SPS with electron and pion beams in the energy range 10-287 GeV. The energy resolution measured for electrons is 10%/square-root E[GeV] with a local constant of 0.2%. Preliminary results on the hadronic section, which for this first exposure had only half of its transverse coverage, look encouraging and show that the calorimeter behaves according to the design figures. C1 UNIV MILAN,DIPARTIMENTO FIS,MILAN,ITALY. UNIV ALBERTA,EDMONTON T6G 2E1,ALBERTA,CANADA. LAPP,ANNECY,FRANCE. UNIV AUTONOMA BARCELONA,BARCELONA,SPAIN. BROOKHAVEN NATL LAB,UPTON,NY 11973. CERN,CH-1211 GENEVA 23,SWITZERLAND. SPP SACLAY,DAPNIA,GIF SUR YVETTE,FRANCE. INFN,SEZ MILANO,MILAN,ITALY. UNIV AUTONOMA MADRID,MADRID 34,SPAIN. CPP,MARSEILLE,FRANCE. UNIV MONTREAL,MONTREAL H3C 3J7,QUEBEC,CANADA. LAL,ORSAY,FRANCE. IN2P3,CNRS,PARIS,FRANCE. MANNE SIEGBANN INST,STOCKHOLM,SWEDEN. UNIV VICTORIA,VICTORIA V8W 2Y2,BC,CANADA. RI Boos, Eduard/D-9748-2012; sala, paola/E-2868-2013; Fernandez, Enrique/L-5387-2014; OI sala, paola/0000-0001-9859-5564; Fernandez, Enrique/0000-0002-6405-9488; Garrido Beltran, Lluis/0000-0001-8883-6539; Re, Valerio/0000-0003-0697-3420 NR 6 TC 1 Z9 1 U1 2 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 1994 VL 344 IS 1 BP 39 EP 46 DI 10.1016/0168-9002(94)90648-3 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NG995 UT WOS:A1994NG99500005 ER PT J AU AMBROSI, G BABUCCI, E BATTISTON, R BIASINI, M EASO, S KRASTEV, V PAULUZZI, M SANTOCCHIA, A BAY, A BURGER, WJ EXTERMANN, P PERRIN, E SUSINNO, G BROOKS, M KAPUSTINSKY, JS KINNISON, WW LEE, DM MILLS, GB THOMPSON, TC DIBITONTO, D PENNINGTON, T SUBHANI, K HAUVILLER, C AF AMBROSI, G BABUCCI, E BATTISTON, R BIASINI, M EASO, S KRASTEV, V PAULUZZI, M SANTOCCHIA, A BAY, A BURGER, WJ EXTERMANN, P PERRIN, E SUSINNO, G BROOKS, M KAPUSTINSKY, JS KINNISON, WW LEE, DM MILLS, GB THOMPSON, TC DIBITONTO, D PENNINGTON, T SUBHANI, K HAUVILLER, C TI DESIGN AND CONSTRUCTION OF DOUBLE-SIDED SILICON LADDERS FOR THE L3 MICROVERTEX DETECTOR SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB The techniques used in the construction of the double-sided ladders for the L3 Silicon Microvertex Detector (SMD) are presented. The detector consists of two cylindrical layers, each of 12 ladders, with double-sided silicon detectors which provide r-phi and z coordinates measurements. This description includes ladder mechanical design and the assembly. A novel solution to readout the z-coordinates is presented. It optimizes very effectively the removal of heat generated by the readout electronics and minimizes the radiation length in the central region. Some results from the survey of the individual ladders are also discussed. C1 INFN, SEZ PERUGIA, I-06100 PERUGIA, ITALY. UNIV ALABAMA, TUSCALOOSA, AL 35486 USA. UNIV PERUGIA, I-06100 PERUGIA, ITALY. UNIV GENEVA, CH-1211 GENEVA 4, SWITZERLAND. LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87544 USA. CERN, CH-1211 GENEVA 23, SWITZERLAND. OI Ambrosi, Giovanni/0000-0001-6977-9559 NR 9 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 EI 1872-9576 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 1994 VL 344 IS 1 BP 133 EP 136 DI 10.1016/0168-9002(94)90660-2 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NG995 UT WOS:A1994NG99500017 ER PT J AU BATTISTON, R BERTUCCI, B BILEI, G CHECCUCCI, B SERVOLI, L WANG, SJ PASSALEVA, G BAY, A BURGER, WJ EXTERMANN, P SUSINNO, G BROOKS, M KAPUSTINSKY, JS KINNISON, WW LEE, DM MILLS, GB AF BATTISTON, R BERTUCCI, B BILEI, G CHECCUCCI, B SERVOLI, L WANG, SJ PASSALEVA, G BAY, A BURGER, WJ EXTERMANN, P SUSINNO, G BROOKS, M KAPUSTINSKY, JS KINNISON, WW LEE, DM MILLS, GB TI EXPERIENCE WITH THE SVX-H CHIP IN THE CONSTRUCTION OF THE L3 SILICON MICROVERTEX DETECTOR SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB The SVX is a charge preamplifier with a sample and hold stage and sparse readout capability developed at the Lawrence Berkeley Laboratory. The SVX radiation hard version has been used by the SMD collaboration to build the L3 Silicon Microvertex Detector where double-sided AC coupled silicon sensors are read out. The SVX-H test procedure in the SMD detector assembly phase will be described as well as the obtained results. C1 INFN, SEZ PERUGIA, I-06100 PERUGIA, ITALY. UNIV PERUGIA, I-06100 PERUGIA, ITALY. INFN, SEZ FIRENZE, I-50100 FLORENCE, ITALY. UNIV GENEVA, CH-1211 GENEVA 4, SWITZERLAND. LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87544 USA. RI Servoli, Leonello/E-6766-2012; bertucci, bruna/J-5237-2012; OI Servoli, Leonello/0000-0003-1725-9185; Bertucci, Bruna/0000-0001-7584-293X NR 7 TC 4 Z9 4 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 EI 1872-9576 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 21 PY 1994 VL 344 IS 1 BP 216 EP 219 DI 10.1016/0168-9002(94)90673-4 PG 4 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA NG995 UT WOS:A1994NG99500030 ER PT J AU EISEMAN, SE ETKIN, A FOLEY, KJ HACKENBURG, RW LONGACRE, RS LOVE, WA MORRIS, TW PLATNER, ED SAULYS, AC LINDENBAUM, SJ CHAN, CS EFSTATHIADIS, EF KRAMER, MA ZHAO, K ZHU, Y HALLMAN, TJ MADANSKY, L AHMAD, S BONNER, BE BUCHANAN, JA CHIOU, CN CLEMENT, JM MUTCHLER, GS AF EISEMAN, SE ETKIN, A FOLEY, KJ HACKENBURG, RW LONGACRE, RS LOVE, WA MORRIS, TW PLATNER, ED SAULYS, AC LINDENBAUM, SJ CHAN, CS EFSTATHIADIS, EF KRAMER, MA ZHAO, K ZHU, Y HALLMAN, TJ MADANSKY, L AHMAD, S BONNER, BE BUCHANAN, JA CHIOU, CN CLEMENT, JM MUTCHLER, GS TI XI-PRODUCTION IN HEAVY-ION COLLISIONS AT THE AGS SO PHYSICS LETTERS B LA English DT Article ID QUARK-GLUON PLASMA; SULFUR TUNGSTEN INTERACTIONS; 200 GEV/C; STRANGENESS; NUCLEON AB We report the first observation of XI- in heavy ion collisions at the AGS. The lifetime of XI- measured agrees very well with the particle data group value. We present the observed XI- effective mass spectrum and the rapidity distribution after acceptance correction. In the measured rapidity region (1.4-2.9) for 14.6 GeV/c Si on Pb, we obtained a yield of 0.25 +/- 0.04 XI- per central event and a ratio of N(XI-)/N(LAMBDA) = 0.12 +/- 0.02 using a fireball+ model (a model which includes a fireball plus a term simulating a cascade) tor acceptance correction (see text for systematic error). This result is larger than any cascade model prediction so far. C1 CUNY CITY COLL,NEW YORK,NY 10031. JOHNS HOPKINS UNIV,BALTIMORE,MD 21218. RICE UNIV,HOUSTON,TX 77251. RP EISEMAN, SE (reprint author), BROOKHAVEN NATL LAB,UPTON,NY 11973, USA. NR 20 TC 20 Z9 20 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD APR 21 PY 1994 VL 325 IS 3-4 BP 322 EP 326 DI 10.1016/0370-2693(94)90019-1 PG 5 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA NH327 UT WOS:A1994NH32700013 ER PT J AU CHANG, JJ AF CHANG, JJ TI TIME-RESOLVED BEAM-QUALITY CHARACTERIZATION OF COPPER-VAPOR LASERS WITH UNSTABLE RESONATORS SO APPLIED OPTICS LA English DT Article DE LASER RESONATORS; METAL-VAPOR LASERS; COPPER-VAPOR LASERS ID APERTURE; OSCILLATOR; DIVERGENCE; COHERENCE AB Beam quality (BQ) of a 4-cm copper-vapor laser (CVL) with unstable resonators of different magnifications was characterized based on time-resolved far-field measurement. It was found that the BQ improvement after each round trip of the cavity cannot be predicted correctly from resonator theory. With a cavity Fresnel number of approximately 300, the achievable CVL BQ at the later part of the pulse was limited to approximately 4 times diffraction limited (x DL), even with a cavity magnification of 130. A pronounced temporal BQ oscillation, which is synchronized with the temporal pulse modulation, was also observed throughout the entire pulse. Examination of the temporal evolution of the far-field spot with use of a gated camera revealed that the strong presence of amplified spontaneous emission (ASE) in the cavity during the entire laser pulse severely limited the achievable BQ because of consecutive cavity feedback that included this highly divergent ASE. BQ deterioration caused by intense ASE throughout the pulse was reduced when a cavity with a smaller Fresnel number was used. RP CHANG, JJ (reprint author), LAWRENCE LIVERMORE NATL LAB, POB 5508, MS L-464, LIVERMORE, CA 94550 USA. NR 19 TC 47 Z9 50 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0003-6935 J9 APPL OPTICS JI Appl. Optics PD APR 20 PY 1994 VL 33 IS 12 BP 2255 EP 2265 PG 11 WC Optics SC Optics GA NF491 UT WOS:A1994NF49100002 PM 20885572 ER PT J AU FRIEMAN, JA GAZTANAGA, E AF FRIEMAN, JA GAZTANAGA, E TI THE 3-POINT FUNCTION AS A PROBE OF MODELS FOR LARGE-SCALE STRUCTURE SO ASTROPHYSICAL JOURNAL LA English DT Article DE COSMOLOGY, THEORY; GALAXIES, CLUSTERING; LARGE-SCALE STRUCTURE OF THE UNIVERSE; METHODS, NUMERICAL ID COLD DARK MATTER; BIASED GALAXY FORMATION; SHANE-WIRTANEN CATALOG; CORRELATION HIERARCHY; DENSITY-FLUCTUATIONS; REDSHIFT SURVEY; IRAS GALAXIES; POWER-LAW; UNIVERSE; SPECTRUM AB We analyze the consequences of models of structure formation for higher order (n-point) galaxy correlation functions in the mildly nonlinear regime. Several variations of the standard Omega=1 cold dark matter model with scale-invariant primordial perturbations have recently been introduced to obtain more power on large scales, R(p) similar to 20 h(-1) Mpc, e.g., low matter-density (nonzero cosmological constant) models, ''tilted'' primordial spectra, and scenarios with a mixture of cold and hot dark matter. They also include models with an effective scale-dependent bias, such as the cooperative galaxy formation scenario of Bower et al. We show that higher-order (n-point) galaxy correlation functions can provide a useful test of such models and can discriminate between models with true large-scale power in the density field and those where the galaxy power arises from scale-dependent bias: a bias with rapid scale dependence leads to a dramatic decrease of the hierarchical amplitudes Q(J) at large scales, r greater than or similar to R(p). Current observational constraints on the three-point amplitudes Q(3) and S-3 can place limits on the bias parameter(s) and appear to disfavor, but not yet rule out, the hypothesis that scale-dependent bias is responsible for the extra power observed on large scales. C1 UNIV OXFORD,DEPT ASTROPHYS,OXFORD OX1 3RH,ENGLAND. RP FRIEMAN, JA (reprint author), FERMILAB NATL ACCELERATOR LAB,NASA,FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510, USA. OI Gaztanaga, Enrique/0000-0001-9632-0815 NR 69 TC 60 Z9 60 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1994 VL 425 IS 2 BP 392 EP 402 DI 10.1086/173995 PN 1 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA PM579 UT WOS:A1994PM57900005 ER PT J AU LATTIMER, JM VANRIPER, KA PRAKASH, M PRAKASH, M AF LATTIMER, JM VANRIPER, KA PRAKASH, M PRAKASH, M TI RAPID COOLING AND THE STRUCTURE OF NEUTRON-STARS SO ASTROPHYSICAL JOURNAL LA English DT Article DE DENSE MATTER; STARS, EVOLUTION; STARS, INTERIORS; STARS, NEUTRON ID DIRECT URCA PROCESS; LIQUID-METAL PHASE; X-RAY-EMISSION; DENSE MATTER; THERMAL-CONDUCTIVITIES; PSR-0656+14; EQUATION; SYSTEMS; STATE; HOT AB Recently proposed neutrino emission processes in high-density matter result in the relatively rapid cooling of a neutron star's interior followed by a precipitous drop in the surface temperature. We show that the time interval between the formation of the neutron star and the drop in the surface temperature is primarily determined by the structure of the neutron star and is relatively insensitive to the rapid cooling mechanism itself. Thus, observations of thermal emissions from neutron stars have the potential for constraining the neutron star's structure and the underlying equation of state of dense matter. C1 LOS ALAMOS NATL LAB,DIV APPL THEORET PHYS,RADIAT TRANSPORT GRP,LOS ALAMOS,NM 87545. SUNY STONY BROOK,DEPT PHYS,STONY BROOK,NY 11794. RP LATTIMER, JM (reprint author), SUNY STONY BROOK,DEPT EARTH & SPACE SCI,STONY BROOK,NY 11794, USA. RI Prakash, Madappa/D-9820-2016 NR 41 TC 137 Z9 137 U1 0 U2 5 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1994 VL 425 IS 2 BP 802 EP 813 DI 10.1086/174025 PN 1 PG 12 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA PM579 UT WOS:A1994PM57900035 ER PT J AU HERANT, M WOOSLEY, SE AF HERANT, M WOOSLEY, SE TI POSTEXPLOSION HYDRODYNAMICS OF SUPERNOVAE IN RED SUPERGIANTS SO ASTROPHYSICAL JOURNAL LA English DT Article DE HYDRODYNAMICS; STARS, INTERIORS; SUPERGIANTS; SUPERNOVAE, GENERAL ID RAYLEIGH-TAYLOR INSTABILITIES; MASSIVE STARS; EARLY EVOLUTION; II SUPERNOVAE; SN-1987A; PROGENITOR; EXPLOSION; MODEL; RATES AB Shock propagation, mixing, and clumping are studied in the explosion of red supergiants as Type II supernovae using a two-dimensional smooth particle hydrodynamic (SPH) code. We show that extensive Rayleigh-Taylor instabilities develop in the ejecta in the wake of the reverse shock wave. In all cases, the shell structure of the progenitor is obliterated to leave a clumpy, well-mixed supernova remnant. However, the occurrence of mass loss during the lifetime of the progenitor can significantly reduce the amount of mixing. These results are independent of the Type II supernova explosion mechanism. C1 LAWRENCE LIVERMORE NATL LAB,DIV GEN STUDIES,LIVERMORE,CA. RP HERANT, M (reprint author), UNIV CALIF SANTA CRUZ,UNIV CALIF OBSERV,LICK OBSERV,BOARD STUDIES ASTRON & ASTROPHYS,SANTA CRUZ,CA 95064, USA. NR 46 TC 100 Z9 100 U1 0 U2 2 PU UNIV CHICAGO PRESS PI CHICAGO PA 5720 S WOODLAWN AVE, CHICAGO, IL 60637 SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD APR 20 PY 1994 VL 425 IS 2 BP 814 EP 828 DI 10.1086/174026 PN 1 PG 15 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA PM579 UT WOS:A1994PM57900036 ER PT J AU DEGIORGI, L OTT, HR DRESSEL, M GRUNER, G FISK, Z AF DEGIORGI, L OTT, HR DRESSEL, M GRUNER, G FISK, Z TI OPTICAL PROBING OF THE ANTIFERROMAGNETIC PHASE-TRANSITIONS IN THE HEAVY-ELECTRON COMPOUNDS U2ZN17 AND UCU5 SO EUROPHYSICS LETTERS LA English DT Article ID MAGNETIC-STRUCTURE; STATE AB We have investigated the complete electrodynamic response of the heavy-electron compounds U2Zn17 and UCu5. Particular emphasis has been devoted to the optical evidence of the antiferromagnetic phase transitions at 9.7 K and 15 K for U2Zn17 and UCu5, respectively. In UCu5, we found an absorption in the far infrared, which is ascribed to excitations across a spin-density-wave-type gap. This feature is absent in U2Zn17. We argue that UCu5 belongs to a characteristically different class of antiferromagnets than U2Zn17 which represents the class of heavy-electron compounds with localized magnetic moments. C1 UNIV CALIF LOS ANGELES,DEPT PHYS,LOS ANGELES,CA 90024. LOS ALAMOS NATL LAB,DIV MAT SCI & TECHNOL,LOS ALAMOS,NM 87545. RP DEGIORGI, L (reprint author), ETH ZURICH,FESTKOERPERPHYS LAB,CH-8093 ZURICH,SWITZERLAND. RI Dressel, Martin/D-3244-2012 NR 13 TC 12 Z9 12 U1 0 U2 0 PU EDITIONS PHYSIQUE PI LES ULIS CEDEX PA Z I DE COURTABOEUF AVE 7 AV DU HOGGAR, BP 112, 91944 LES ULIS CEDEX, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD APR 20 PY 1994 VL 26 IS 3 BP 221 EP 226 DI 10.1209/0295-5075/26/3/011 PG 6 WC Physics, Multidisciplinary SC Physics GA NJ651 UT WOS:A1994NJ65100011 ER PT J AU HOBBS, JD MAJUMDER, SA LUO, L SICKELSMITH, GA QUIRKE, JME MEDFORTH, CJ SMITH, KM SHELNUTT, JA AF HOBBS, JD MAJUMDER, SA LUO, L SICKELSMITH, GA QUIRKE, JME MEDFORTH, CJ SMITH, KM SHELNUTT, JA TI STRUCTURAL HETEROGENEITY AND COORDINATION CHEMISTRY OF NICKEL(II) OCTAETHYL-MESO-NITROPORPHYRINS SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID RESONANCE RAMAN-SPECTRA; NUCLEAR MAGNETIC-RESONANCE; N-15 SUBSTITUTED DERIVATIVES; LIGHT-ABSORPTION PROPERTIES; PORPHYRIN FORCE-FIELD; PHOTOSYNTHETIC CHROMOPHORES; METAL-COMPLEXES; ZINC-COMPLEXES; NMR-SPECTRA; MODELS AB The role of steric crowding of peripheral substituents in causing nonplanar distortions of the porphyrin macrocycle has been investigated in a series of nickel(II) meso-nitrooctaethylporphyrins as models for protein-induced nonplanar distortions of metal-tetrapyrrole cofactors. UV-visible absorption spectra, resonance Raman spectra, nuclear magnetic resonance spectra, and molecular mechanics calculations are given for nickel(II) derivatives of 5-mono-, 5,15-di-, 5,10-di-, 5,10,15-tri-, and 5,10,15,20-meso-nitro-substituted octaethylporphyrins. The frequencies of the structure-sensitive Raman lines are found to shift to lower energies in response to sterically induced nonplanar distortion of the porphyrin macrocycle rather than in response to the addition of a strong electron-withdrawing nitro substituent. The Raman spectra of all except tetranitrooctaethylporphyrin show spectroscopic evidence of heterogeneity resulting from the presence of conformers with differing degrees of nonplanarity. Evidence from UV-visible absorption spectra, nuclear magnetic resonance spectra, and molecular mechanics calculations suggests that nickel tetranitrooctaethylporphyrin in solution may exhibit conformers with different types of nonplanar distortions which however do not differ in the relative degree of distortion. We find that the effect of increasing distortion on the chemical reactivity with axial ligating agents, which normally acts to lower the affinity, is overcome in the case of the nitrooctaethylporphyrin series by the increasing electron depletion of the porphyrin ring as the number of nitro substituents increases. C1 UNIV NEW MEXICO,DEPT CHEM,ALBUQUERQUE,NM 87131. FLORIDA INT UNIV,DEPT CHEM,MIAMI,FL 33199. LAWRENCE LIVERMORE NATL LAB,DEPT CHEM,DAVIS,CA 95616. RP HOBBS, JD (reprint author), SANDIA NATL LABS,DEPT FUEL SCI,POB 5800,ALBUQUERQUE,NM 87185, USA. RI Shelnutt, John/A-9987-2009; Medforth, Craig/D-8210-2013; REQUIMTE, FMN/M-5611-2013; REQUIMTE, UCIBIO/N-9846-2013; Smith, Kevin/G-1453-2011 OI Shelnutt, John/0000-0001-7368-582X; Medforth, Craig/0000-0003-3046-4909; Smith, Kevin/0000-0002-6736-4779 NR 57 TC 73 Z9 73 U1 0 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD APR 20 PY 1994 VL 116 IS 8 BP 3261 EP 3270 DI 10.1021/ja00087a011 PG 10 WC Chemistry, Multidisciplinary SC Chemistry GA NG889 UT WOS:A1994NG88900011 ER PT J AU DONG, ZC CORBETT, JD AF DONG, ZC CORBETT, JD TI NA2K21TL19, A NOVEL THALLIUM COMPOUND CONTAINING ISOLATED TL(5)(7-) AND TL(9)(9-) GROUPS - A NEW HYPOELECTRONIC CLUSTER SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID HOMOPOLYATOMIC ANIONS; CRYSTAL-STRUCTURES; ELEMENTS; SALTS AB The title compound is synthesized in high yield by fusion of the elements in sealed Ta containers followed by slow cooling to and annealing at 250 degrees C. The structure was established by single crystal means (Cmcm, Z = 4, a = 11.345 (2) Angstrom, b = 13.807 (3) Angstrom, c = 41.832 (8) Angstrom, R/R(w) = 5.3/4.3%). The independent unit contains two Tl-5 and one Tl-9 units ordered in layers and well separated by the cations which bond to, and bridge between, faces, edges, and vertices of the clusters. The sodium appears essential in this role. The former cluster, a distorted trigonal bipyramid (C-m symmetry), is proportioned as is Pb-5(2-), etc. and should be analogously formulated as the isoelectronic Tl-5(7-) according to EHMO calculations. The new Tl-9 geometry (C-2v, d(Tl-Tl) = 3.13-3.44 Angstrom) can be obtained by substantial elongation of two side edges of a tricapped trigonal prism (D-3h) so that the intervening face-capping atom moves close to that face and becomes eight-bonded. MO calculations illustrate how this distortion of either Bi-9(5+)- or B9H92--like polyhedra affords a hypoelectronic state for Tl-9(9-) (2n skeletal electrons). More direct geometric and electronic relationships are found on removal of four adjoining vertices from a centered icosahedral Tl-13 The compound is diamagnetic and a very poor conductor (rho(293) similar to 800 mu Omega.cm). C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. NR 42 TC 61 Z9 61 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD APR 20 PY 1994 VL 116 IS 8 BP 3429 EP 3435 DI 10.1021/ja00087a030 PG 7 WC Chemistry, Multidisciplinary SC Chemistry GA NG889 UT WOS:A1994NG88900030 ER PT J AU KUNG, PJ PETERSON, EJ FLYNN, ER MOMBOURQUETTE, CB FOLTYN, SR BRAINARD, RJ AF KUNG, PJ PETERSON, EJ FLYNN, ER MOMBOURQUETTE, CB FOLTYN, SR BRAINARD, RJ TI PHASE EVOLUTION AND SUPERCONDUCTIVITY EMERGENCE IN REPETITIVELY ANNEALED BI-SR-CA-CU-O THIN-FILMS SO PHYSICA C LA English DT Article ID HIGH-TC PHASE; DEPOSITION TECHNIQUE; INSITU; OXYGEN; SYSTEM; GROWTH; CVD AB Bi(Pb)-Sr-Ca-Cu-O superconducting thin films on MgO (100) substrates have been made by laser deposition in combination with repetitive post-annealing treatments. The films of nominal composition (Bi, Pb)2Sr2Ca2Cu3O10+delta were deposited at 400-degrees-C and then heated in air at a rate of 75-80-degrees-C/min, held at 845-847-degrees-C for 10 min, quenched to 600-degrees-C at a rate of 80-degreesC/min, and slowly cooled at a rate of 3.3-degrees-C/min to room temperature. The Bi2Sr2CaCu2O8+delta (2212) phase was found to crystallize first in these as-deposited amorphous films, whereas the (Bi, Pb)2Sr2Ca2Cu3O10+delta (2223) phase was grown in large quantities by repeating the annealing cycle. With this protocol, the 2223 phase is developed more effectively than that observed in the long period of annealing, and the formation of pinholes on the surface is significantly reduced. Surface morphologies examined by scanning electron microscopy (SEM) are improved for films repetitively annealed under reduced pressure conditions. The results of magnetic susceptibility measurements on these films correspond well with the phase behavior seen by X-ray diffractometry (XRD) analyses. The transport critical current densities, J(c), of the film are 9.0x10(5) and 5.5x10(4) A/cm2 at 5 and 40 K, respectively. The magnetization critical current densities derived from M(H) data at 6 K are two orders of magnitude higher in the orientation of H perpendicular-to c-axis than of H parallel-to c-axis. As a preliminary study, XRD line-broadening analysis was performed to investigate the effects of lattice strain and crystallite size in the set of films that were annealed at various temperatures for 3-6 h. The microstrain values are in the range of 10(-4)-10(-3), and the crystallite sizes in films obtained for the 2212 and 2223 phases depend on annealing time, temperature, and cooling rate. Microstrain associated with the 2223 phase is more sensitive to annealing parameters. These results suggest that XRD line-broadening analysis may be a valuable method to study the growth mechanism and material properties of the repetitively annealed films. C1 LOS ALAMOS NATL LAB,SUPERCOND TECHNOL CTR,LOS ALAMOS,NM 87545. UNIV WISCONSIN,MAT SCI PROGRAM,MADISON,WI 53706. RP KUNG, PJ (reprint author), LOS ALAMOS NATL LAB,BIOPHYS GRP,MS M715,LOS ALAMOS,NM 87545, USA. NR 41 TC 0 Z9 1 U1 1 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD APR 20 PY 1994 VL 224 IS 1-2 BP 58 EP 68 DI 10.1016/0921-4534(94)90605-X PG 11 WC Physics, Applied SC Physics GA NH559 UT WOS:A1994NH55900009 ER PT J AU SMITH, MG PHILLIPS, DS PETERSON, DE WILLIS, JO AF SMITH, MG PHILLIPS, DS PETERSON, DE WILLIS, JO TI ATOMIC REDISTRIBUTION AND MASS-TRANSPORT IN THE FORMATION OF BI1.80PB0.43SR1.71CA2.14CU3O10+X SO PHYSICA C LA English DT Article ID CU-O SUPERCONDUCTOR; PHASE AB A sample of nominal Bi1.80Pb0.43Sr1.71Ca2.14Cu3O10+x (Bi-2223) composition consisting primarily of fine grains of Bi2Sr2CaCu2O8+x (Bi-2212) and Ca2PbO4 was synthesized under pure oxygen by a solid-state reaction. This assemblage was then converted to large grains of the 110 K superconducting Bi-222 3 phase by annealing at 860-degrees-C in air. Utilizing scanning electron microscopy and wavelength dispersive X-ray spectroscopy we show that a redistribution of Ca and Pb occurs throughout the matrix during the formation of Bi-2223. These results indicate that the driving force for Pb doped Bi-2223 formation may be due to the large change in entropy caused by melting of one or more of the precursor phases and mixing of the liquid constituents. Melting may be driven by the dependence of the conversion Pb4+ <-> Pb2+ on the oxygen partial pressure, with Pb2+ in Ca2PbO4 and Pb2+ in the Bi-2223 phase. RP SMITH, MG (reprint author), LOS ALAMOS NATL LAB,CTR SUPERCOND TECHNOL,LOS ALAMOS,NM 87545, USA. NR 12 TC 18 Z9 18 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD APR 20 PY 1994 VL 224 IS 1-2 BP 168 EP 174 DI 10.1016/0921-4534(94)90618-1 PG 7 WC Physics, Applied SC Physics GA NH559 UT WOS:A1994NH55900022 ER PT J AU OPRESKO, DM CAIRNS, SD AF OPRESKO, DM CAIRNS, SD TI DESCRIPTION OF THE NEW GENUS ALLOPATHES (CNIDARIA, ANTIPATHARIA) AND ITS TYPE SPECIES CIRRIPATHES DESBONNI SO PROCEEDINGS OF THE BIOLOGICAL SOCIETY OF WASHINGTON LA English DT Article AB The rarely collected species originally described as Cirripathes desbonni is redescribed based on two specimens. A neotype is designated because the type is presumed to be lost. A new genus, Allopathes, is proposed for this species based on its unusual colony form: numerous elongate, mostly unbranched stems originating from a short, trunk-like base. Antipathes robillardi Bell is also placed in this genus, which gives the genus a range of western Atlantic and Mauritius at 129-161 m. C1 SMITHSONIAN INST,DEPT INVERTEBRATE ZOOL,WASHINGTON,DC 20560. RP OPRESKO, DM (reprint author), OAK RIDGE NATL LAB,DIV HLTH SCI RES,OAK RIDGE,TN 37830, USA. NR 8 TC 3 Z9 3 U1 0 U2 0 PU BIOL SOC WASHINGTON PI WASHINGTON PA NAT MUSEUM NAT HIST SMITHSONIAN INST, WASHINGTON, DC 20560 SN 0006-324X J9 P BIOL SOC WASH JI Proc. Biol. Soc. Wash. PD APR 20 PY 1994 VL 107 IS 1 BP 185 EP 192 PG 8 WC Biology SC Life Sciences & Biomedicine - Other Topics GA NG958 UT WOS:A1994NG95800020 ER PT J AU SPRUNGER, PT PLUMMER, EW AF SPRUNGER, PT PLUMMER, EW TI THE INTERACTION OF HYDROGEN WITH SIMPLE METAL-SURFACES SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 13th European Conference on Surface Science (ECOSS-13) CY AUG 30-SEP 04, 1993 CL UNIV WARWICK, ARTS CTR, WARWICK, ENGLAND SP BRIT VACUUM COUNCIL, EUROPEAN PHYS SOC, INT UNION VACUUM SCI TECH & APPL, INST PHYS, THIN FILMS & SURFACES GRP HO UNIV WARWICK, ARTS CTR ID ADSORPTION SITES; BINDING-ENERGIES; CHEMISORPTION; H-2; AL; MG; NA AB The interaction of atomic and molecular hydrogen with a number of simple metal surfaces (Mg(0001), Mg(1120BAR), Li(110), K(110)) has been studied using EELS, TDS, and core-level spectroscopy. Although no evidence for molecular hydrogen adsorption is observed at greater-than-or-equal-to 100 K, atomic hydrogen is bound to the surface in a strongly chemisorbed phase (hydride). When the substrate is annealed, hydrogen is irreversibly absorbed into the bulk region; in the case of the alkali metals, clusters of bulk hydride are nucleated within the bulk clean metal. Overall trends of the H/simple metal interaction are discussed in light of theoretical (jellium model) predictions and experimental results from similar systems. C1 UNIV PENN, DEPT PHYS, PHILADELPHIA, PA 19104 USA. UNIV TENNESSEE, DEPT PHYS, KNOXVILLE, TN 37996 USA. OAK RIDGE NATL LAB, DIV SOLID STATE, OAK RIDGE, TN 37831 USA. NR 18 TC 28 Z9 30 U1 2 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 20 PY 1994 VL 307 BP 118 EP 123 DI 10.1016/0039-6028(94)90380-8 PN A PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA NH824 UT WOS:A1994NH82400021 ER PT J AU SWIECH, W RASTOMJEE, CS IMBIHL, R EVANS, JW RAUSENBERGER, B ENGEL, W SCHMID, AK BRADSHAW, AM ZEITLER, E AF SWIECH, W RASTOMJEE, CS IMBIHL, R EVANS, JW RAUSENBERGER, B ENGEL, W SCHMID, AK BRADSHAW, AM ZEITLER, E TI ON THE COMPLEX STRUCTURE OF REACTION-DIFFUSION FRONTS OBSERVED DURING CO OXIDATION ON PT(100) SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 13th European Conference on Surface Science (ECOSS-13) CY AUG 30-SEP 04, 1993 CL UNIV WARWICK, ARTS CTR, WARWICK, ENGLAND SP BRIT VACUUM COUNCIL, EUROPEAN PHYS SOC, INT UNION VACUUM SCI TECH & APPL, INST PHYS, THIN FILMS & SURFACES GRP HO UNIV WARWICK, ARTS CTR ID KINETIC OSCILLATIONS; ADSORPTION; SURFACES AB In the catalytic oxidation of CO on Pt{100}, we have been able to identify, using small-area LEED, the different adsorbate-covered regions which constitute the reaction-diffusion fronts observed in photoelectron emission microscopy. The resulting concentration profile is simulated in one dimension with the help of a simple two-variable model derived from the Langmuir-Hinshelwood mechanism. The characteristic features of the experiment are reproduced if it is assumed that the CO diffusion coefficient is strongly enhanced (by a factor of 7) at coverages corresponding to the (square-root 2 x square-root 2)R45-degrees-CO phase and reduced by surface defects. C1 MAX PLANCK GESELL, FRITZ HABER INST, FARADAYWEG 4-6, D-14195 BERLIN, GERMANY. UNIV WROCLAW, INST EXPTL PHYS, PL-50204 WROCLAW, POLAND. IOWA STATE UNIV SCI & TECHNOL, AMES LAB, AMES, IA 50011 USA. NR 20 TC 24 Z9 24 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 20 PY 1994 VL 307 BP 138 EP 142 PN A PG 5 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA NH824 UT WOS:A1994NH82400024 ER PT J AU DOLL, R KOTTCKE, M HEINZ, K HAMMER, L MULLER, K ZEHNER, DM AF DOLL, R KOTTCKE, M HEINZ, K HAMMER, L MULLER, K ZEHNER, DM TI APPLICATION OF CHEMICAL TENSOR LEED TO MOXRE1-X(100) SURFACES SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 13th European Conference on Surface Science (ECOSS-13) CY AUG 30-SEP 04, 1993 CL UNIV WARWICK, ARTS CTR, WARWICK, ENGLAND SP BRIT VACUUM COUNCIL, EUROPEAN PHYS SOC, INT UNION VACUUM SCI TECH & APPL, INST PHYS, THIN FILMS & SURFACES GRP HO UNIV WARWICK, ARTS CTR ID ENERGY ELECTRON-DIFFRACTION; APPROXIMATION; ALLOYS AB We present and apply an extension of the perturbation method tensor LEED in order to handle surface stoichiometry, i.e. the substitution of surface atoms by chemically different species. This avoids the need for new full dynamical calculations for surfaces of different chemical composition and allows fast access to their LEED intensities. This ''chemical tensor LEED'' is applied to the chemically disordered alloy MoxRe1-x(100) for x = 0.75, 0.85 and 0.95 for which LEED intensities were measured. Oscillatory layer dependent segregation is found in agreement with conventional LEED analyses. Even small Re concentrations strongly modify the structure of the pure Mo(100) surface, i.e. the surface reconstruction is lifted and multilayer relaxation effects are increased. C1 OAK RIDGE NATL LAB, OAK RIDGE, TN 37831 USA. RP DOLL, R (reprint author), UNIV ERLANGEN NURNBERG, LEHRSTUHL FESTKORPERPHYS, STAUDTSTR 7, D-91058 ERLANGEN, GERMANY. RI Hammer, Lutz/D-9863-2013 NR 22 TC 31 Z9 31 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 20 PY 1994 VL 307 BP 434 EP 439 DI 10.1016/0039-6028(94)90432-4 PN A PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA NH824 UT WOS:A1994NH82400073 ER PT J AU HAAS, J ROOS, KR JESINA, A TRINGIDES, MC AF HAAS, J ROOS, KR JESINA, A TRINGIDES, MC TI SURFACE-DIFFUSION IN TEMPORALLY AND SPATIALLY INHOMOGENEOUS SYSTEMS SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 13th European Conference on Surface Science (ECOSS-13) CY AUG 30-SEP 04, 1993 CL UNIV WARWICK, ARTS CTR, WARWICK, ENGLAND SP BRIT VACUUM COUNCIL, EUROPEAN PHYS SOC, INT UNION VACUUM SCI TECH & APPL, INST PHYS, THIN FILMS & SURFACES GRP HO UNIV WARWICK, ARTS CTR ID 110 PLANE; TUNGSTEN; OXYGEN; COVERAGE AB Non-equilibrium processes in an overlayer with the system evolving between two different states (i.e., ordering, disordering, adsorption) can be used to study surface diffusion. Diffraction experiments on O/W(110) at high coverage measure an activation energy E(d) = 0.6 +/- 0.05 eV during ordering and E(d) = 1 +/- 0.05 eV during disordering. These results are consistent with other diffusion experiments carried out with the fluctuation and Boltzmann-Matano methods. The difference between the measured activation energies can be accounted for in terms of the interactions which contribute differently in different overlayer configurations. Computer simulations on lattice gas models illustrate the dependence on the configuration, by comparing diffusion coefficients obtained with different methods. C1 IOWA STATE UNIV SCI & TECHNOL, DEPT PHYS & ASTRON, AMES LAB, AMES, IA 50011 USA. NR 14 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 20 PY 1994 VL 307 BP 465 EP 470 DI 10.1016/0039-6028(94)90438-3 PN A PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA NH824 UT WOS:A1994NH82400079 ER PT J AU WEITERING, HH CHEN, J PEREZSANDOZ, R DINARDO, NJ AF WEITERING, HH CHEN, J PEREZSANDOZ, R DINARDO, NJ TI ELECTRON LOCALIZATION AND THE NONMETAL-TO-METAL TRANSITION AT ULTRATHIN ALKALI-METAL/SI(111) INTERFACES SO SURFACE SCIENCE LA English DT Article; Proceedings Paper CT 13th European Conference on Surface Science (ECOSS-13) CY AUG 30-SEP 04, 1993 CL UNIV WARWICK, ARTS CTR, WARWICK, ENGLAND SP BRIT VACUUM COUNCIL, EUROPEAN PHYS SOC, INT UNION VACUUM SCI TECH & APPL, INST PHYS, THIN FILMS & SURFACES GRP HO UNIV WARWICK, ARTS CTR ID SURFACE-STATES; OVERLAYER; METALLIZATION; SI(001)-(2X1); ADSORPTION; CS AB The K/Si(111)7 X 7 and K/Si(111)(square-root 3 x square-root 3)R30-degrees-B interfaces are nonmetallic at room temperature saturation coverage. In contrast, the Cs/Si(111)7 X 7 interface metallizes below saturation coverage. Possible mechanisms of electron localization in pre-metallized films will be discussed. We conclude that electron correlation effects are important in determining the electronic properties of these interfaces. C1 DREXEL UNIV, DEPT PHYS & ATMOSPHER SCI, PHILADELPHIA, PA 19104 USA. UNIV PENN, DEPT PHYS, PHILADELPHIA, PA 19104 USA. OAK RIDGE NATL LAB, DIV SOLID STATE, OAK RIDGE, TN 37831 USA. UNIV PENN, DEPT MAT SCI & ENGN, PHILADELPHIA, PA 19104 USA. RP WEITERING, HH (reprint author), UNIV TENNESSEE, DEPT PHYS & ASTRON, KNOXVILLE, TN 37996 USA. NR 21 TC 20 Z9 21 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 20 PY 1994 VL 307 BP 978 EP 983 DI 10.1016/0039-6028(94)91527-X PN B PG 6 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA NH823 UT WOS:A1994NH82300063 ER PT J AU HOLBROOK, SR AF HOLBROOK, SR TI CRYSTALLOGRAPHIC STUDIES OF RNA OLIGOMERS INCORPORATING INTERNAL LOOPS SO FASEB JOURNAL LA English DT Meeting Abstract C1 LAWRENCE BERKELEY LAB,DIV STRUCT BIOL,BERKELEY,CA 94720. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 19 PY 1994 VL 8 IS 7 BP A1262 EP A1262 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA NH516 UT WOS:A1994NH51600237 ER PT J AU KIM, SH AF KIM, SH TI STRUCTURAL BASIS FOR ACTIVATION OF CDK2, A CELL-CYCLE KINASE SO FASEB JOURNAL LA English DT Meeting Abstract C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 19 PY 1994 VL 8 IS 7 BP A1322 EP A1322 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA NH516 UT WOS:A1994NH51600583 ER PT J AU LI, D STEVENS, FJ SCHIFFER, M ANDERSON, LE AF LI, D STEVENS, FJ SCHIFFER, M ANDERSON, LE TI MECHANISM OF LIGHT-MODULATION - IDENTIFICATION OF POTENTIAL REDOX-SENSITIVE CYSTEINES IN CHLOROPLAST FRUCTOSE-1,6-BISPHOSPHATASE AND SEDOHEPTULOSE-1,7-BISPHOSPHATASE SO FASEB JOURNAL LA English DT Meeting Abstract C1 UNIV ILLINOIS,DEPT BIOL SCI,CHICAGO,IL 60607. ARGONNE NATL LAB,ARGONNE,IL 60439. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 19 PY 1994 VL 8 IS 7 BP A1290 EP A1290 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA NH516 UT WOS:A1994NH51600400 ER PT J AU MILNE, JC FURLONG, D HANNA, PC WALL, J COLLIER, RJ AF MILNE, JC FURLONG, D HANNA, PC WALL, J COLLIER, RJ TI ANTHRAX PROTECTIVE ANTIGEN FORMS RING-SHAPED OLIGOMERS DURING INTOXICATION OF MAMMALIAN-CELLS SO FASEB JOURNAL LA English DT Meeting Abstract C1 HARVARD UNIV,SCH MED,BOSTON,MA 02115. BROOKHAVEN NATL LAB,UPTON,NY 11973. NR 0 TC 1 Z9 1 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 19 PY 1994 VL 8 IS 7 BP A1464 EP A1464 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA NH516 UT WOS:A1994NH51601406 ER PT J AU NANDAGOPAL, K TADAKI, DK NIYOGI, SK AF NANDAGOPAL, K TADAKI, DK NIYOGI, SK TI MUTATIONAL ANALYSIS OF LEUCINE-15 OF HUMAN EPIDERMAL GROWTH-FACTOR (HEGF) SO FASEB JOURNAL LA English DT Meeting Abstract C1 UNIV TENNESSEE,OAK RIDGE GRAD SCH BIOMED SCI,OAK RIDGE,TN 37830. OAK RIDGE NATL LAB,DIV BIOL,PROT ENGN PROGRAM,OAK RIDGE,TN 37831. NR 0 TC 2 Z9 2 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 19 PY 1994 VL 8 IS 7 BP A1460 EP A1460 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA NH516 UT WOS:A1994NH51601382 ER PT J AU NICHOLSON, C KNAPP, J GRIFFIN, GD AF NICHOLSON, C KNAPP, J GRIFFIN, GD TI EFFECT OF ELECTROMAGNETIC-RADIATION ON MODEL MEMBRANES SO FASEB JOURNAL LA English DT Meeting Abstract C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. NR 0 TC 0 Z9 0 U1 0 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 19 PY 1994 VL 8 IS 7 BP A1339 EP A1339 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA NH516 UT WOS:A1994NH51600682 ER PT J AU OU, MC LEE, TC SNYDER, F AF OU, MC LEE, TC SNYDER, F TI SUBCELLULAR AND TISSUE DISTRIBUTION OF PLATELET-ACTIVATING-FACTOR (PAF) TRANSACETYLASE SO FASEB JOURNAL LA English DT Meeting Abstract C1 OAK RIDGE ASSOCIATED UNIV,DIV MED SCI,OAK RIDGE,TN 37831. NR 1 TC 1 Z9 1 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 19 PY 1994 VL 8 IS 7 BP A1402 EP A1402 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA NH516 UT WOS:A1994NH51601050 ER PT J AU PERRY, J LENNON, G AF PERRY, J LENNON, G TI OPTIMIZED SEQUENCING PRIMERS FOR AUTOMATED DNA-SEQUENCING SO FASEB JOURNAL LA English DT Meeting Abstract C1 LAWRENCE LIVERMORE NATL LAB,LIVERMORE,CA 94550. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 19 PY 1994 VL 8 IS 7 BP A1362 EP A1362 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA NH516 UT WOS:A1994NH51600818 ER PT J AU TADAKI, DK CAMPION, SR NIYOGI, SK AF TADAKI, DK CAMPION, SR NIYOGI, SK TI ANALYSIS OF THE TYROSINE RESIDUES AT POSITION-22 AND POSITION-29 OF HUMAN EPIDERMAL GROWTH-FACTOR (HEGF) BY SITE-DIRECTED MUTAGENESIS SO FASEB JOURNAL LA English DT Meeting Abstract C1 UNIV TENNESSEE,OAK RIDGE GRAD SCH BIOMED SCI,OAK RIDGE,TN 37830. OAK RIDGE NATL LAB,DIV BIOL,PROT ENGN PROGRAM,OAK RIDGE,TN 37831. NR 0 TC 3 Z9 3 U1 0 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD APR 19 PY 1994 VL 8 IS 7 BP A1459 EP A1459 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA NH516 UT WOS:A1994NH51601381 ER PT J AU HENDERSON, CC ROHLFING, CM ASSINK, RA CAHILL, PA AF HENDERSON, CC ROHLFING, CM ASSINK, RA CAHILL, PA TI C60H4 - KINETICS AND THERMODYNAMICS OF MULTIPLE ADDITION TO C-60 SO ANGEWANDTE CHEMIE-INTERNATIONAL EDITION IN ENGLISH LA English DT Article ID SEMIEMPIRICAL CALCULATIONS C1 SANDIA NATL LABS,ALBUQUERQUE,NM 87185. NR 18 TC 107 Z9 107 U1 0 U2 1 PU VCH PUBLISHERS INC PI DEERFIELD BEACH PA 303 NW 12TH AVE, DEERFIELD BEACH, FL 33442-1788 SN 0570-0833 J9 ANGEW CHEM INT EDIT JI Angew. Chem.-Int. Edit. Engl. PD APR 18 PY 1994 VL 33 IS 7 BP 786 EP 788 DI 10.1002/anie.199407861 PG 3 WC Chemistry, Multidisciplinary SC Chemistry GA NG649 UT WOS:A1994NG64900027 ER PT J AU OZBAY, E MICHEL, E TUTTLE, G BISWAS, R SIGALAS, M HO, KM AF OZBAY, E MICHEL, E TUTTLE, G BISWAS, R SIGALAS, M HO, KM TI MICROMACHINED MILLIMETER-WAVE PHOTONIC BAND-GAP CRYSTALS SO APPLIED PHYSICS LETTERS LA English DT Article ID PERIODIC DIELECTRIC STRUCTURES AB We have developed a new technique for fabricating three-dimensional photonic band-gap crystals. Our method utilizes an orderly stacking of micromachined (110) silicon wafers to build the periodic structure. A structure with a full three-dimensional photonic band gap centered near 100 GHz was measured, with experimental results in good agreement with theoretical predictions. This basic approach described should be extendable to build structures with photonic band-gap frequencies ranging from 30 GHz to 3 THz. C1 IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT ELECT ENGN,AMES,IA 50011. IOWA STATE UNIV SCI & TECHNOL,DEPT PHYS & ASTRON,AMES,IA 50011. RP OZBAY, E (reprint author), IOWA STATE UNIV SCI & TECHNOL,MICROELECTR RES CTR,AMES,IA 50011, USA. RI Ozbay, Ekmel/B-9495-2008 NR 10 TC 195 Z9 209 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 18 PY 1994 VL 64 IS 16 BP 2059 EP 2061 PG 3 WC Physics, Applied SC Physics GA NG495 UT WOS:A1994NG49500005 ER PT J AU CHOQUETTE, KD RICHIE, DA LEIBENGUTH, RE AF CHOQUETTE, KD RICHIE, DA LEIBENGUTH, RE TI TEMPERATURE-DEPENDENCE OF GAIN-GUIDED VERTICAL-CAVITY SURFACE-EMITTING LASER POLARIZATION SO APPLIED PHYSICS LETTERS LA English DT Article AB We show the polarization characteristics of gain-guided vertical-cavity surface emitting lasers are related to the temperature-dependent cavity optical resonance and laser gain spectral alignment. Simultaneous nearly degenerate orthogonal eigen polarization states are observed at and above lasing threshold. The partitioning of power between the linear polarization states is shown to depend on the relative spectral overlap of the cavity resonance of each state with the gain. Near the condition of cavity resonance/gain alignment, an abrupt switch in the dominant eigen polarization with a region of polarized output fluctuations is evident. Rotation of the eigen polarization directions relative to the crystal axes is also observed at temperatures where the gain is blue shifted from the cavity resonances. C1 AT&T BELL LABS,STC,BREINIGSVILLE,PA 18031. RP CHOQUETTE, KD (reprint author), SANDIA NATL LABS,ALBUQUERQUE,NM 87185, USA. NR 14 TC 189 Z9 189 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 18 PY 1994 VL 64 IS 16 BP 2062 EP 2064 DI 10.1063/1.111737 PG 3 WC Physics, Applied SC Physics GA NG495 UT WOS:A1994NG49500006 ER PT J AU ITOH, KM HALLER, EE HANSEN, WL BEEMAN, JW FARMER, JW RUDNEV, A TIKHOMIROV, A OZHOGIN, VI AF ITOH, KM HALLER, EE HANSEN, WL BEEMAN, JW FARMER, JW RUDNEV, A TIKHOMIROV, A OZHOGIN, VI TI NEUTRON TRANSMUTATION DOPING OF ISOTOPICALLY ENGINEERED GE SO APPLIED PHYSICS LETTERS LA English DT Article ID GERMANIUM AB We report a novel approach for obtaining precise control of both p- and n-type dopant concentrations in bulk Ge single crystals. High-purity Ge single crystals of controlled Ge-74/Ge-70 isotope composition ratios were grown and subsequently doped by the neutron transmutation doping (NTD) technique. The resulting net-impurity concentrations and the compensation ratios were precisely determined by the thermal neutron fluence and the [Ge-74]/[Ge-70] ratios of the starting Ge materials, respectively. Application of NTD to seven crystals with O less-than-or-equal-to [Ge-74]/[Ge-70] less-than-or-equal-to 4.34 lead to p-type Ge:Ga,As with compensation ratios in the range 0-0.76. The ability to grow crystals with accurately controlled Ge isotope mixtures allows us to obtain ratios anywhere between 0 and 1 for both p- and n-type doping. C1 LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. UNIV MISSOURI,COLUMBIA,MO 65211. IV KURCHATOV ATOM ENERGY INST,MOSCOW 123182,RUSSIA. RP ITOH, KM (reprint author), UNIV CALIF BERKELEY,BERKELEY,CA 94720, USA. RI Itoh, Kohei/C-5738-2014 NR 17 TC 32 Z9 32 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD APR 18 PY 1994 VL 64 IS 16 BP 2121 EP 2123 DI 10.1063/1.111703 PG 3 WC Physics, Applied SC Physics GA NG495 UT WOS:A1994NG49500027 ER PT J AU BONSIGNORE, PV AF BONSIGNORE, PV TI BENEFITS OF EYE PROTECTION SO CHEMICAL & ENGINEERING NEWS LA English DT Letter C1 ARGONNE NATL LAB,ARGONNE,IL 60439. NR 2 TC 0 Z9 0 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0009-2347 J9 CHEM ENG NEWS JI Chem. Eng. News PD APR 18 PY 1994 VL 72 IS 16 BP 2 EP 2 PG 1 WC Chemistry, Multidisciplinary; Engineering, Chemical SC Chemistry; Engineering GA NG034 UT WOS:A1994NG03400003 ER PT J AU COWLEY, RA WARD, RCC WELLS, MR MATSUDA, M STERNLIEB, B AF COWLEY, RA WARD, RCC WELLS, MR MATSUDA, M STERNLIEB, B TI THE MAGNETIC-STRUCTURE AND PHASE-TRANSITIONS OF HOLMIUM-YTTRIUM ALLOYS SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID CRITICAL-BEHAVIOR; SINGLE-CRYSTAL; MODELS; HEAT; HO; DY AB Films of holmium-yttrium alloys were grown by molecular beam epitaxy (MBE), and found to have a mosaic spread of about 0.2-degrees, a concentration uniformity of better than 0.5% and a concentration accuracy of better than 2%. Neutron scattering techniques at the Brookhaven HFBR were used to study the magnetic structures and phase transitions of four samples Ho(x)Y1-x with x = 1.0, 0.9, 0.7 and 0.5 in zero field, and one sample with x = 0.7 as a function of applied magnetic field. In zero field the structures are all helical structures with the moments in the basal planes and the wavevectors of the helix along the hexagonal c-axis. At T(N), the wavevectors are 0.282c*, and decrease on cooling, until at low temperatures the structures become commensurate with wavevectors of 1/5c*(x = 1), 2/9c*(x = 0.9), 1/4c*(x = 0.7) and 4/15c*(x = 0.5). The critical exponent beta was measured for each of the films and is consistent for all of the materials with beta = 0.50 +/- 0.05. There is some rounding at T(N) which may be due to the second and long length scale that has been found in pure holmium. When a magnetic field between 0 and 6 T is applied in the basal plane, the phase diagram for x = 0.7 has six phases. On cooling in a low field the sequence is paramagnetic, incommensurate helix, q = 1/4 helix, while for fields above 4 T, the sequence is paramagnetic, incommensurate fan, q = 1/4 fan. On increasing the field the helical phase goes directly to the fan phase, but on decreasing the field from the q = 1/4 fan phase, the system shows a q = 1/4 helifan phase between the fan and helical phases. C1 INST PHYS & CHEM RES, WAKO, SAITAMA 35101, JAPAN. BROOKHAVEN NATL LAB, UPTON, NY 11973 USA. RP UNIV OXFORD, CLARENDON LAB, PARKS RD, OXFORD, ENGLAND. RI Matsuda, Masaaki/A-6902-2016 OI Matsuda, Masaaki/0000-0003-2209-9526 NR 17 TC 17 Z9 17 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 EI 1361-648X J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD APR 18 PY 1994 VL 6 IS 16 BP 2985 EP 2998 DI 10.1088/0953-8984/6/16/004 PG 14 WC Physics, Condensed Matter SC Physics GA NH054 UT WOS:A1994NH05400004 ER PT J AU ALFORD, M MARCHRUSSELL, J AF ALFORD, M MARCHRUSSELL, J TI RADIATIVELY INDUCED 1ST-ORDER PHASE-TRANSITIONS - THE NECESSITY OF THE RENORMALIZATION-GROUP SO NUCLEAR PHYSICS B LA English DT Article ID INFLATIONARY UNIVERSE; FINITE TEMPERATURE; GAUGE-THEORIES; BARYOGENESIS; FLUCTUATIONS; FLATNESS; HORIZON AB We advocate a (Wilson) renormalization-group (RG) treatment of finite-temperature first-order phase transitions, in particular those driven by radiative corrections such as occur in the standard model, and other spontaneously broken gauge theories. We introduce the scale-dependent coarse-grained free energy S(LAMBDA[phi]) which we explicitly calculate, using the Wilson RG and a (4 - epsilon)-expansion, for a scalar toy model that shares many features of the gauged case. As argued by Langer and others, the dynamics of the phase transition are described by S(LAMBDA[phi]) with I/LAMBDA of order the bubble wall thickness, and not by the usual (RG-improved) finite-temperature effective action which is reproduced by S(LAMBDA[phi]) for LAMBDA --> 0. We argue that for weakly first-order transitions (such as that in the standard model) the (4 - epsilon)-expansion is necessary to control an inevitable growth of the effective scale-dependent coupling towards the strong-coupling regime, and that diagrammatic resummation techniques are unlikely to be appropriate. C1 LAWRENCE BERKELEY LAB, THEORET PHYS GRP, BERKELEY, CA 94720 USA. RP CORNELL UNIV, NUCL STUDIES LAB, ITHACA, NY 14853 USA. NR 40 TC 26 Z9 26 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD APR 18 PY 1994 VL 417 IS 3 BP 527 EP 552 DI 10.1016/0550-3213(94)90483-9 PG 26 WC Physics, Particles & Fields SC Physics GA NM361 UT WOS:A1994NM36100007 ER PT J AU HSU, CT CHENG, CZ HELANDER, P SIGMAR, DJ WHITE, R AF HSU, CT CHENG, CZ HELANDER, P SIGMAR, DJ WHITE, R TI PARTICLE DYNAMICS IN CHIRPED-FREQUENCY FLUCTUATIONS SO PHYSICAL REVIEW LETTERS LA English DT Article ID ALFVEN EIGENMODES AB Hamiltonian systems describing particle motion in a wave with time-dependent (chirped) frequency are studied. The wave is found to form a single-node separatrix (bucket) moving in the phase space at a rate proportional to that of the frequency change. Particles trapped inside the bucket undergo convection, while untrapped particles colliding with the bucket get a resonant kick, in phase space. In toroidal systems, these effects can result in a large radial convective flux roughly proportional to the size of the bucket and the frequency chirping. Possible applications of this novel mechanism to tokamak plasmas are discussed. C1 CHALMERS UNIV TECHNOL,INST ELECTROMAGNET FIELD THEORY & PLASMA PHYS,S-41296 GOTHENBURG,SWEDEN. PRINCETON UNIV,PRINCETON PLASMA PHYS LAB,PRINCETON,NJ 08543. RP HSU, CT (reprint author), MIT,CTR PLASMA FUS,167 ALBANY ST,NW16-260,CAMBRIDGE,MA 02139, USA. RI Cheng, Chio/K-1005-2014 NR 18 TC 35 Z9 35 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 18 PY 1994 VL 72 IS 16 BP 2503 EP 2507 DI 10.1103/PhysRevLett.72.2503 PG 5 WC Physics, Multidisciplinary SC Physics GA NG380 UT WOS:A1994NG38000001 ER PT J AU ZUREK, WH PAZ, JP AF ZUREK, WH PAZ, JP TI DECOHERENCE, CHAOS, AND THE 2ND LAW SO PHYSICAL REVIEW LETTERS LA English DT Article ID QUANTUM BROWNIAN-MOTION; WAVE PACKET; DISSIPATION; MECHANICS; ENVIRONMENT; OSCILLATOR; SYSTEMS AB Quantum wave function of a chaotic system spreads rapidly over distances on which the potential is significantly nonlinear. As a result, the effective force is no longer just a gradient of the potential, and predictions of classical and quantum dynamics begin to differ. We show how the interaction with the environment limits distances over which quantum coherence can persist, and therefore reconciles quantum dynamics with classical Hamiltonian chaos. The entropy production rate for such open chaotic systems exhibits a sharp transition between reversible and dissipative regimes, where it is set by the chaotic dynamics. RP LOS ALAMOS NATL LAB, T-6 MAIL STOP B288, LOS ALAMOS, NM 87545 USA. RI Paz, Juan/C-5947-2008 NR 30 TC 296 Z9 296 U1 3 U2 20 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 18 PY 1994 VL 72 IS 16 BP 2508 EP 2511 DI 10.1103/PhysRevLett.72.2508 PG 4 WC Physics, Multidisciplinary SC Physics GA NG380 UT WOS:A1994NG38000002 ER PT J AU GATES, E TURNER, MS AF GATES, E TURNER, MS TI HALO COLD DARK-MATTER AND MICROLENSING SO PHYSICAL REVIEW LETTERS LA English DT Article ID GALACTIC HALOS; IRAS GALAXIES; UNIVERSE; INFALL; MASS AB We discuss expectations, for the abundance of baryons and cold dark matter (CDM) in our own galactic halo and show that in plausible CDM models the local CDM density is at least 10(-25) g cm-3. Based upon a suite of two-component halo models we conclude that the microlensing of stars in the Large Magellanic Cloud by dark halo stars is not a sensitive probe of the local CDM density. Thus, even if the number of candidate microlensing events increases significantly, experiments designed to detect halo CDM are still warranted. C1 FERMILAB NATL ACCELERATOR LAB,NASA FERMILAB ASTROPHYS CTR,BATAVIA,IL 60510. UNIV CHICAGO,ENRICO FERMI INST,DEPT PHYS,CHICAGO,IL 60637. RP GATES, E (reprint author), UNIV CHICAGO,ENRICO FERMI INST,DEPT ASTRON & ASTROPHYS,CHICAGO,IL 60637, USA. NR 33 TC 26 Z9 26 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 18 PY 1994 VL 72 IS 16 BP 2520 EP 2523 DI 10.1103/PhysRevLett.72.2520 PG 4 WC Physics, Multidisciplinary SC Physics GA NG380 UT WOS:A1994NG38000005 ER PT J AU LEITCH, MJ BOISSEVAIN, J CAREY, TA JANSEN, DM JEPPESEN, RG KAPUSTINSKY, JS LANE, DW LILLBERG, JW MCGAUGHEY, PL MOSS, JM PENG, JC ISENHOWER, LD SADLER, ME SCHNATHORST, R GIDAL, G HO, PM KOWITT, MS LUK, KB PRIPSTEIN, D LEDERMAN, LM SCHUB, MH BROWN, CN COOPER, WE GLASS, HD GOUNDER, KN MISHRA, CS KAPLAN, DM LUEBKE, WR MARTIN, VM PRESTON, RS SA, J TANIKELLA, V CHILDERS, R DARDEN, CW WILSON, JR CHEN, YC KIANG, GC TENG, PK AF LEITCH, MJ BOISSEVAIN, J CAREY, TA JANSEN, DM JEPPESEN, RG KAPUSTINSKY, JS LANE, DW LILLBERG, JW MCGAUGHEY, PL MOSS, JM PENG, JC ISENHOWER, LD SADLER, ME SCHNATHORST, R GIDAL, G HO, PM KOWITT, MS LUK, KB PRIPSTEIN, D LEDERMAN, LM SCHUB, MH BROWN, CN COOPER, WE GLASS, HD GOUNDER, KN MISHRA, CS KAPLAN, DM LUEBKE, WR MARTIN, VM PRESTON, RS SA, J TANIKELLA, V CHILDERS, R DARDEN, CW WILSON, JR CHEN, YC KIANG, GC TENG, PK TI NUCLEAR-DEPENDENCE OF NEUTRAL-D-MESON PRODUCTION BY 800-GEV/C PROTONS SO PHYSICAL REVIEW LETTERS LA English DT Article ID PRODUCTION CROSS-SECTION; STRIP DETECTOR READOUT; J-PSI SUPPRESSION; CHARM PRODUCTION; J/PSI-PRODUCTION; A-DEPENDENCE; 800 GEV/C; EMULSION INTERACTIONS; COLLISIONS; SYSTEMATICS AB The nuclear dependence for 800 GeV/c proton production of neutral D mesons has been measured near x(F) = 0 in Experiment 789 at Fermilab. D mesons from beryllium and gold targets were detected with a pair spectrometer and a silicon vertex detector via their decay D --> Kpi. No nuclear dependence is found, with a measured alpha = 1.02 +/- 0.03 +/- 0.02. The measured differential cross section, dsigma/dx(F), for neutral-D-meson production at [x(F)] = 0.031 is 58 +/- 3 +/- 7 mub/nucleon. The integrated cross section obtained by extrapolation of the measured cross section to all x(F) is 17.7 +/- 0.9 +/- 3.4 mub/nucleon and is consistent with previous measurements. C1 ABILENE CHRISTIAN UNIV, ABILENE, TX 79699 USA. UNIV CALIF BERKELEY, BERKELEY, CA 94720 USA. UNIV CHICAGO, CHICAGO, IL 60637 USA. FERMILAB NATL ACCELERATOR LAB, BATAVIA, IL 60510 USA. NO ILLINOIS UNIV, DE KALB, IL 60115 USA. UNIV S CAROLINA, COLUMBIA, SC 29208 USA. NATL CHENG KUNG UNIV, INST PHYS, TAINAN, TAIWAN. ACAD SINICA, INST PHYS, TAIPEI 115, TAIWAN. LAWRENCE BERKELEY LAB, BERKELEY, CA 94720 USA. RP LOS ALAMOS NATL LAB, LOS ALAMOS, NM 87545 USA. NR 33 TC 92 Z9 92 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 18 PY 1994 VL 72 IS 16 BP 2542 EP 2545 DI 10.1103/PhysRevLett.72.2542 PG 4 WC Physics, Multidisciplinary SC Physics GA NG380 UT WOS:A1994NG38000011 ER PT J AU DIAMOND, PH LIANG, YM CARRERAS, BA TERRY, PW AF DIAMOND, PH LIANG, YM CARRERAS, BA TERRY, PW TI SELF-REGULATING SHEAR-FLOW TURBULENCE - A PARADIGM FOR THE L TO H TRANSITION SO PHYSICAL REVIEW LETTERS LA English DT Article ID POLOIDAL ROTATION; HIGH-BETA; TOKAMAK; GENERATION; MODEL AB A self-consistent model of the L to H transition is derived from coupled nonlinear envelope equations for the fluctuation level and radial electric field shear E(r)'. These equations exhibit a supercritical bifurcation between dual L-mode and H-mode fixed points. The transition occurs when the turbulence level is large enough for the Reynolds stress drive to overcome the damping of the E x B flow. This defines a power threshold for the transition, which is calculated and found to be consistent with experimental findings. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37830. UNIV WISCONSIN,MADISON,WI 53706. GEN ATOM CO,SAN DIEGO,CA 92186. RP DIAMOND, PH (reprint author), UNIV CALIF SAN DIEGO,LA JOLLA,CA 92093, USA. NR 21 TC 269 Z9 269 U1 4 U2 26 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 18 PY 1994 VL 72 IS 16 BP 2565 EP 2568 DI 10.1103/PhysRevLett.72.2565 PG 4 WC Physics, Multidisciplinary SC Physics GA NG380 UT WOS:A1994NG38000017 ER PT J AU WANG, CZ HO, KM AF WANG, CZ HO, KM TI STRUCTURE, DYNAMICS, AND ELECTRONIC-PROPERTIES OF DIAMOND-LIKE AMORPHOUS-CARBON - REPLY SO PHYSICAL REVIEW LETTERS LA English DT Note C1 IOWA STATE UNIV SCI & TECHNOL, DEPT PHYS, AMES, IA 50011 USA. RP WANG, CZ (reprint author), IOWA STATE UNIV SCI & TECHNOL, AMES LAB, AMES, IA 50011 USA. NR 8 TC 3 Z9 3 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 18 PY 1994 VL 72 IS 16 BP 2667 EP 2667 DI 10.1103/PhysRevLett.72.2667 PG 1 WC Physics, Multidisciplinary SC Physics GA NG380 UT WOS:A1994NG38000045 ER PT J AU CAMASSA, R AF CAMASSA, R TI DO RESONANTLY FORCED INTERNAL SOLITARY WAVES PROTECT THE FUEL OF HURRICANES - COMMENT SO PHYSICAL REVIEW LETTERS LA English DT Note C1 LOS ALAMOS NATL LAB, CTR NONLINEAR STUDIES, LOS ALAMOS, NM 87545 USA. RP CAMASSA, R (reprint author), LOS ALAMOS NATL LAB, DIV THEORET, LOS ALAMOS, NM 87545 USA. NR 4 TC 0 Z9 0 U1 1 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD APR 18 PY 1994 VL 72 IS 16 BP 2668 EP 2668 DI 10.1103/PhysRevLett.72.2668 PG 1 WC Physics, Multidisciplinary SC Physics GA NG380 UT WOS:A1994NG38000046 ER PT J AU MAAS, FE BRAUN, B GEERDS, H JUNGMANN, K MATTHIAS, BE PUTLITZ, GZ REINHARD, I SCHWARZ, W WILLMANN, L ZHANG, L BAIRD, PEG SANDARS, PGH WOODMAN, GS EATON, GH MATOUSEK, P TONER, WT TOWRIE, M BARR, JRM FERGUSON, AI PERSAUD, MA RIIS, E BERKELAND, D BOSHIER, MG HUGHES, VW WOODLE, KA AF MAAS, FE BRAUN, B GEERDS, H JUNGMANN, K MATTHIAS, BE PUTLITZ, GZ REINHARD, I SCHWARZ, W WILLMANN, L ZHANG, L BAIRD, PEG SANDARS, PGH WOODMAN, GS EATON, GH MATOUSEK, P TONER, WT TOWRIE, M BARR, JRM FERGUSON, AI PERSAUD, MA RIIS, E BERKELAND, D BOSHIER, MG HUGHES, VW WOODLE, KA TI A MEASUREMENT OF THE 1S-2S TRANSITION FREQUENCY IN MUONIUM SO PHYSICS LETTERS A LA English DT Article ID LAMB SHIFT; LASER SPECTROSCOPY; RYDBERG CONSTANT; HYDROGEN; N=2; POLARIZATION; VACUUM; ATOMS AB Doppler-free two-photon laser spectroscopy has been employed to measure the 1(2)S1/2-2(2)S1/2 transition in the muonium atom (mu+e-). A value of 2 455 529 002 (33) (46) MHz has been obtained, which agrees with QED calculations within two standard deviations. The Lamb shift contributions are tested to the level 8 x 10(-3). The corresponding measurements in hydrogen and deuterium using the same apparatus and laser system provide a test of the applied systematic corrections and have verified the systematic error of 46 MHz quoted. The mass of the positive muon has been derived from the isotope shift in this transition and yields a value of 105.65880 (29) (43) MeV/c2. C1 UNIV HEIDELBERG,INST PHYS,D-69120 HEIDELBERG,GERMANY. UNIV OXFORD,CLARENDON LAB,OXFORD OX1 3PU,ENGLAND. RUTHERFORD APPLETON LAB,DIDCOT OX11 0QX,OXON,ENGLAND. UNIV SOUTHAMPTON,DEPT PHYS,SOUTHAMPTON SO9 5NH,HANTS,ENGLAND. UNIV STRATHCLYDE,DEPT PHYS & APPL PHYS,GLASGOW G4 0NG,SCOTLAND. YALE UNIV,GIBBS LAB,NEW HAVEN,CT 06511. BROOKHAVEN NATL LAB,UPTON,NY 11973. RI Matousek, Pavel/D-5750-2011; Jungmann, Klaus/A-7142-2010; jungmann, klaus/H-1581-2013; Boshier, Malcolm/A-2128-2017 OI Matousek, Pavel/0000-0003-0912-5339; jungmann, klaus/0000-0003-0571-4072; Boshier, Malcolm/0000-0003-0769-1927 NR 32 TC 46 Z9 46 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD APR 18 PY 1994 VL 187 IS 3 BP 247 EP 254 DI 10.1016/0375-9601(94)90903-2 PG 8 WC Physics, Multidisciplinary SC Physics GA NG607 UT WOS:A1994NG60700009 ER PT J AU SUPERKO, HR MYLL, J DIRICCO, C WILLIAMS, PT BORTZ, WM WOOD, PD AF SUPERKO, HR MYLL, J DIRICCO, C WILLIAMS, PT BORTZ, WM WOOD, PD TI EFFECTS OF CESSATION OF CAFFEINATED-COFFEE CONSUMPTION ON AMBULATORY AND RESTING BLOOD-PRESSURE IN MEN SO AMERICAN JOURNAL OF CARDIOLOGY LA English DT Article ID CORONARY HEART-DISEASE; CARDIOVASCULAR-DISEASE; MYOCARDIAL-INFARCTION; DRINKING; SMOKERS; MORTALITY; SMOKING; FRAMINGHAM; MALES; AGE AB Coffee consumption has bees weakly linked to high blood pressure (BP). The hypothesis that cessation of caffeinated-coffee consumption lowers ambulatory BP was tested in men in a randomized trial. One hundred eighty-six middle-aged, normotensive, male, habitual caffeinated-coffee consumers were recruited. Of these subjects, 150 had sufficiently complete, ambulatory BP measurements for analysis. After 2 months of standard caffeinated-coffee consumption, subjects were randomized to consume an equal amount of the same standard caffeinated coffee or a standard decaffeinated coffee, or to discontinue coffee consumption for 2 months. Diet composition, body weight and exercise did not change. Resting BP and heart rate were not different between the groups before and after intervention. In comparison with the continued caffeinated-coffee group (control), the decaffeinated-coffee group revealed significant reductions in mean ambulatory systolic BP during the morning (-4.0 +/- 11 mm Hg; p = 0.014), afternoon (-5.3 +/- 10 mm Hg; p = 0.001) and evening (-3.2 +/- 10 mm Hg; p = 0.003) hours, reductions in mean ambulatory diastolic BP during the afternoon (-1.8 +/- 10 mm Hg; p = 0.063) and evening (-1.8 +/- 10 mm Hg; p = 0.059) hours and no change in ambulatory heart rate. The group randomized to no coffee revealed significant reductions in ambulatory systolic BP during the morning (-4.1 +/- 9 mm Hg; p = 0.007), afternoon (-3.3 +/- 10 mm Hg; p = 0.023) and evening (-2.2 +/- 11 mm Hg; p = 0.015) hours, significant reductions in ambulatory diastolic BP during the afternoon (-2.6 +/- 6 mm Hg; p = 0.006) and evening (-2.1 +/- 6 mm Hg; p = 0.016) hours, and no significant change in ambulatory heart rate. This suggests that cessation of caffeinated coffee results in significant reductions in ambulatory systolic and diastolic BP in normotensive men, which are not apparent from resting BP measurements. C1 STANFORD UNIV,STANFORD CTR RES DIS PREVENT,STANFORD,CA. RP SUPERKO, HR (reprint author), UNIV CALIF BERKELEY,LAWRENCE BERKELEY LAB,CHOLESTEROL RES CTR,DEPT MOLEC & NUCL MED,BERKELEY,CA 94720, USA. OI Superko, H. Robert/0000-0002-3542-0393 FU NHLBI NIH HHS [HL 24462, HL 33577] NR 44 TC 22 Z9 22 U1 0 U2 1 PU EXCERPTA MEDICA INC PI NEW YORK PA 245 WEST 17TH STREET, NEW YORK, NY 10011 SN 0002-9149 J9 AM J CARDIOL JI Am. J. Cardiol. PD APR 15 PY 1994 VL 73 IS 11 BP 780 EP 784 DI 10.1016/0002-9149(94)90881-8 PG 5 WC Cardiac & Cardiovascular Systems SC Cardiovascular System & Cardiology GA NG546 UT WOS:A1994NG54600010 PM 8160616 ER PT J AU VO-DINH, T PAL, A PAL, T AF VO-DINH, T PAL, A PAL, T TI PHOTOACTIVATED LUMINESCENCE METHOD FOR RAPID SCREENING OF POLYCHLORINATED-BIPHENYLS SO ANALYTICAL CHEMISTRY LA English DT Article ID ROOM-TEMPERATURE PHOSPHORESCENCE; THIN-LAYER CHROMATOGRAPHY; PCBS AB This paper describes a new method based on enhanced photoactivated luminescence (EPL) for rapid detection of polychlorinated biphenyls (PCBs). The EPL method described here is a unique procedure combining several processes including (i) photoactivation by UV irradiation, (ii) excitation of the photoproduct complex, and (iii) fluorescence detection of the product. The EPL procedure is simple and rapid and can de performed as a spot test method under field conditions. The methodology for determination of total chlorine content of complex PCB mixtures is described. Limits of detection of PCBs are in the parts-per-billion range. RP VO-DINH, T (reprint author), OAK RIDGE NATL LAB, DIV HLTH & SAFETY RES, ADV MONITORING DEV GRP, OAK RIDGE, TN 37831 USA. NR 14 TC 20 Z9 22 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD APR 15 PY 1994 VL 66 IS 8 BP 1264 EP 1268 DI 10.1021/ac00080a011 PG 5 WC Chemistry, Analytical SC Chemistry GA NF411 UT WOS:A1994NF41100014 ER PT J AU STEMMLER, EA BUCHANAN, MV HURST, GB HETTICH, RL AF STEMMLER, EA BUCHANAN, MV HURST, GB HETTICH, RL TI STRUCTURAL CHARACTERIZATION OF POLYCYCLIC AROMATIC HYDROCARBON DIHYDRODIOL EPOXIDE DNA-ADDUCTS USING MATRIX-ASSISTED LASER DESORPTION/IONIZATION FOURIER-TRANSFORM MASS-SPECTROMETRY SO ANALYTICAL CHEMISTRY LA English DT Article ID FAST-ATOM-BOMBARDMENT; NUCLEIC-ACID CONSTITUENTS; DESORPTION IONIZATION; DIOL EPOXIDES; NUCLEOSIDES; IDENTIFICATION; METABOLITES; BINDING; OLIGONUCLEOTIDES; CARCINOGENESIS AB Matrix-assisted laser desorption/ionization (MALDI) Fourier transform ion cyclotron resonance mass spectrometry (FTMS) has been applied for the structural characterization of four polycyclic aromatic hydrocarbon dihydrodiol epoxide (PAH-DE) adducts, including the 5,6-dimethylchrysene DE adduct of 2'-deoxyadenosine, the 5-methyl- and 5,6-dimethylchrysene DE adducts of 2'-deoxyguanosine, and the benzo[a]pyrene-DE adduct of 2'-deoxyguanosyl 3'-phosphate. Measurement of positive and negative ion mass spectre, accurate mass determinations, and CID experiments were carried out using 10-40 ng (20-70 pmol) of sample. An evaluation of five MALDI matrices showed that matrix selection can be used to control the degree of analyte fragmentation. Three MALDI matrices commonly used for the analysis of proteins (sinapinic acid, ferulic acid, 2,5-dihydroxybenzoic acid) gave positive ion adduct mass spectra showing protonated or sodiated molecular ions accompanied by abundant, structurally informative fragment ions. Fragmentation was significantly reduced when working with two matrices used for oligonucleotide analysis (an anthranilic-nicotinic acid mixture and 3-hydroxypicolinic acid). Using the CID capabilities of FTMS, isolation and activation of the MALDI-produced ions was used to provide additional structural information. While characteristic negative ions were not detected for the adenosyl adduct, the guanosyl and guanosyl 3'-phosphate adducts gave [M - H](-) ions when the anthranilic-nicotinic acid matrix mixture was used. The guanosyl adducts also showed [M - H - 2H(2)O](-) fragments. Compared with FAB or FAB-MS/MS for the analysis of underivatized PAH-DE adducts, MALDI-FTMS signals are long-lived, the direct MALDI-FT mass spectra show more structurally informative fragments, and accurate mass and CID experiments require lower sample quantities. C1 OAK RIDGE NATL LAB,OAK RIDGE,TN 37831. RP STEMMLER, EA (reprint author), BOWDOIN COLL,DEPT CHEM,BRUNSWICK,ME 04011, USA. RI Hettich, Robert/N-1458-2016; Buchanan, Michelle/J-1562-2016 OI Hettich, Robert/0000-0001-7708-786X; Buchanan, Michelle/0000-0002-8078-4575 FU NCI NIH HHS [NCIYO1-CP-20512-13] NR 68 TC 28 Z9 28 U1 1 U2 9 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD APR 15 PY 1994 VL 66 IS 8 BP 1274 EP 1285 DI 10.1021/ac00080a013 PG 12 WC Chemistry, Analytical SC Chemistry GA NF411 UT WOS:A1994NF41100016 PM 8210044 ER PT J AU TISSUE, BM PICKETT, DA FEAREY, BL AF TISSUE, BM PICKETT, DA FEAREY, BL TI MEASUREMENT OF HIGH-DYNAMIC-RANGE THORIUM ISOTOPIC-RATIOS USING CONTINUOUS-WAVE RESONANCE IONIZATION MASS-SPECTROMETRY SO ANALYTICAL CHEMISTRY LA English DT Article ID JUAN-DE-FUCA; GORDA RIDGES; SYSTEMATICS; SPECTROSCOPY; SELECTIVITY; RHENIUM; OSMIUM; TH AB We have developed continuous-wave resonance ionization mass spectrometry (cw-RIMS) methods to measure Th-230/Th-232 isotopic ratios. The overall Th ionization detection efficiency using a 1 + 1 RIMS process (narrow-band laser for the resonant step and a high-power ultraviolet- (UV-) Ar+ laser for the ionization step) is 0.10%. Measurement of the Th-230/Th-232 ratio (4.096 X 10(-4)) of a laboratory standard shows that the cw-RIMS method has internal precision comparable to thermal ionization mass spectrometry measurements (similar to 0.5%, 2 sigma(m)), but introduces a small bias (2-4%), which is correctable by calibration with an isotopic standard. The bias is due to intrinsic laser-induced biases in the 1 + 1 RIMS process and in a nonresonant process due to the UV-Ar+ laser alone, which contributes similar to 3% to the total Th+ signal. Laser power dependence experiments show that neither the resonant nor the ionization step is entirely saturated; therefore, the isotopic bias is probably due to differences in the transition strengths of the isotopes. The reproducibility of the RIMS-induced bias is dependent on the reproducibility of the laser parameters, but can be kept within the precision of the measurements (similar to 0.5%). Ratio measurements of the 4.096 x 10(-4) standard and of a sample of Table Mountain Latite demonstrates that cw-RIMS can accurately measure Th-230/Th-233 ratios when the laser-induced biases are calibrated and kept constant. C1 LOS ALAMOS NATL LAB, NIS 7, LOS ALAMOS, NM 87532 USA. VIRGINIA POLYTECH INST & STATE UNIV, DEPT CHEM, BLACKSBURG, VA 24061 USA. LOS ALAMOS NATL LAB, CST 8, LOS ALAMOS, NM 87545 USA. NR 44 TC 5 Z9 5 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 EI 1520-6882 J9 ANAL CHEM JI Anal. Chem. PD APR 15 PY 1994 VL 66 IS 8 BP 1286 EP 1293 DI 10.1021/ac00080a014 PG 8 WC Chemistry, Analytical SC Chemistry GA NF411 UT WOS:A1994NF41100017 ER PT J AU QUIRKE, JME ADAMS, CL VANBERKEL, GJ AF QUIRKE, JME ADAMS, CL VANBERKEL, GJ TI CHEMICAL DERIVATIZATION FOR ELECTROSPRAY-IONIZATION MASS-SPECTROMETRY .1. ALKYL-HALIDES, ALCOHOLS, PHENOLS, THIOLS, AND AMINES SO ANALYTICAL CHEMISTRY LA English DT Article ID ION TRAP; PEPPERMINT OIL; CHROMATOGRAPHY; BIOMOLECULES; CHLOROPHENOLS; DESORPTION; PEPTIDES; SPECTRA; CATIONS; ACETATE AB Derivatization strategies and specific derivatization reactions for conversion of simple alkyl halides, alcohols, phenols, thiols, and amines to ionic or solution-ionizable derivatives, that is ''electrospray active'' (ES-active) forms of the analyte, are presented. Use of these reactions allows detection of analytes among those listed that are not normally amenable to analysis by electrospray ionization mass spectrometry (ES-MS). In addition, these reactions provide for analysis specificity and flexibility through functional group specific derivatization and through the formation of derivatives that can be detected in positive ion or in negative ion mode. For a few of the functional groups, amphoteric derivatives are formed that can be analyzed in either positive or negative ion modes. General synthetic strategies for transformation of members of these five compound classes to ES-active species are presented along with illustrative examples of suitable derivatives. Selected derivatives were prepared using model compounds and the ES mass spectra obtained for these derivatives are discussed. The analytical utility of derivatization for ES-MS analysis is illustrated in three experiments: (1) specific detection of the major secondary alcohol in oil of peppermint, (2) selective detection of phenols within a synthetic mixture of phenols, and (3) identification of the medicinal amines within a commercially available cold medication as primary, secondary or tertiary. C1 FLORIDA INT UNIV,DEPT CHEM,MIAMI,FL 33199. RP QUIRKE, JME (reprint author), OAK RIDGE NATL LAB,DIV CHEM & ANALYT SCI,OAK RIDGE,TN 37831, USA. NR 65 TC 139 Z9 142 U1 2 U2 31 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD APR 15 PY 1994 VL 66 IS 8 BP 1302 EP 1315 DI 10.1021/ac00080a016 PG 14 WC Chemistry, Analytical SC Chemistry GA NF411 UT WOS:A1994NF41100019 ER PT J AU MADOK, JH HAEGEL, NM MOLL, A HALLER, EE YU, KM AF MADOK, JH HAEGEL, NM MOLL, A HALLER, EE YU, KM TI DIRECT MEASUREMENT OF C-AS IN GROUP-III+C COIMPLANTED GAAS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID ENCAPSULATED CZOCHRALSKI GAAS; LOCALIZED VIBRATIONAL-MODE; GALLIUM-ARSENIDE; IMPLANTED GAAS; POINT-DEFECTS; CARBON; IMPURITIES; SEMICONDUCTORS; ENERGIES; PAIRS AB The effect of In and Ga coimplanted with C into GaAs on the concentration Of C(As) has been investigated by local vibrational mode spectroscopy, Rutherford backscattering, particle-induced x-ray emission, and Hall effect. The dose of the C was fixed at 5 X 10(14) cm-2, 27 keV, while the doses of either In, 185 keV, or Ga, 160 keV, ranged from 5 X 10(13) to 5 X 10(15) cm-2. Based on the Hall-effect and local vibrational mode data, 99% of the C, when implanted alone and annealed, is not located as isolated, substitutional atoms on either sublattice, but in an inactive complex. The coimplanted group-III species acts to increase both the concentration of C(As) ([C(As)]) and the sheet hole concentration. For coimplant doses of 5 X 10(13) and 5 X 10(14) cm-2, these values are in good agreement. Increasing the dose of the group-III coimplanted ion to 5 X 10(15) cm-2 results in a hole concentration that is 45 % less than the [C(As)] and the coimplanted ions begin to occupy nonsubstitutional sites. The reduction in the concentration of holes due to C(As) at the highest dose of coimplanted ion appears to be caused by a compensating defect which limits the maximum sheet hole concentration obtainable by the coimplantation technique in GaAs. C1 UNIV CALIF LOS ANGELES,DEPT MAT SCI & ENGN,LOS ANGELES,CA 90024. UNIV CALIF BERKELEY,DEPT MAT SCI & MINERAL ENGN,BERKELEY,CA 94720. LAWRENCE BERKELEY LAB,BERKELEY,CA 94720. RI Yu, Kin Man/J-1399-2012 OI Yu, Kin Man/0000-0003-1350-9642 NR 32 TC 4 Z9 4 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1994 VL 75 IS 8 BP 3829 EP 3834 DI 10.1063/1.356061 PG 6 WC Physics, Applied SC Physics GA NG577 UT WOS:A1994NG57700018 ER PT J AU RAISER, GF WISE, JL CLIFTON, RJ GRADY, DE COX, DE AF RAISER, GF WISE, JL CLIFTON, RJ GRADY, DE COX, DE TI PLATE IMPACT RESPONSE OF CERAMICS AND GLASSES SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID THERMAL-EXPANSION ANISOTROPY; STAR-SHAPED FLYER; MECHANICAL-PROPERTIES; FAILURE WAVES; NANOINDENTATION; MICROCRACKING; FRACTURE; STRESS AB Soft-recovery plate impact experiments have been conducted to study the evolution of damage in polycrystalline Al2O3 samples. Examination of the recovered samples by means of scanning electron microscopy and transmission electron microscopy has revealed that microcracking occurs along grain boundaries; the cracks appear to emanate from grain-boundary triple points. Velocity-time profiles measured at the rear surface of the momentum trap indicate that the compressive pulse is not fully elastic even when the maximum amplitude of the pulse is significantly less than the Hugoniot elastic limit. Attempts to explain this seemingly anomalous behavior are summarized. Primary attention is given to the role of the intergranular glassy phase which arises from sintering aids and which is ultimately forced into the interfaces and voids between the ceramic grains. Experiments are reported on the effects of grain size and glass content on the resistance of the sample to damage during the initial compressive pulse. To further understand the role of the glass, plate impact experiments were conducted on glass with chemical composition comparable to that which is present in the ceramic. These experiments were designed to gain further insight into the possibility of ''failure waves'' in glasses under compressive loading. C1 BROWN UNIV,DIV ENGN,PROVIDENCE,RI 02912. SANDIA NATL LABS,ALBUQUERQUE,NM 87185. NR 28 TC 81 Z9 81 U1 2 U2 20 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1994 VL 75 IS 8 BP 3862 EP 3869 DI 10.1063/1.356066 PG 8 WC Physics, Applied SC Physics GA NG577 UT WOS:A1994NG57700023 ER PT J AU FUERST, CD BREWER, EG MISHRA, RK ZHU, YM WELCH, DO AF FUERST, CD BREWER, EG MISHRA, RK ZHU, YM WELCH, DO TI DIE-UPSET PR-FE-B-TYPE MAGNETS FROM MELT-SPUN RIBBONS SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID SINTERED MAGNETS; SPIN-REORIENTATION; PERMANENT-MAGNETS; COERCIVITY; CU; TEXTURE; DEPENDENCE; MODEL AB In order to optimize the magnetic properties of die-upset Pr-Fe-B magnets, we have systematically altered alloy compositions, including partial substitution of cobalt and neodymium, and low-level additions of gallium. In general, the remanences of Pr-Fe-B die-upset magnets were lower by approximately 1 kG, and coercivities were higher by approximately 4 kOe, than analogous Nd-Fe-B magnets. The microstructure of the Pr-Fe-B die-upset magnets was similar to Nd-Fe-B magnets. Both systems are two phase, consisting of oriented flat platelet-shaped grains of 2-14-1 separated by a rare earth-rich intergranular phase. The intergranular phase is thicker for the Pr-Fe-B magnets, resulting in enhanced magnetic domain wall pinning and increased coercivity. Even higher coercivities were obtained with small amounts of cobalt substitution (less-than-or-equal-to 5 at. % of the transition metal) and by very low-level additions of gallium (less-than-or-equal-to 0.5 at. %). The largest remanence (B(r) = 13.7 kG) for a Pr-based 75% die-upset magnet was obtained with the alloy (R13TM81B6)0.9975Ga0.25, Where R= (Pr0.8Nd0.2) and TM = (Fe0.95Co0.05). C1 BROOKHAVEN NATL LAB, DEPT APPL SCI, UPTON, NY 11973 USA. RP FUERST, CD (reprint author), GM CORP, CTR NAO RES & DEV, DEPT PHYS, WARREN, MI 48090 USA. NR 30 TC 13 Z9 13 U1 0 U2 4 PU AMER INST PHYSICS PI MELVILLE PA CIRCULATION & FULFILLMENT DIV, 2 HUNTINGTON QUADRANGLE, STE 1 N O 1, MELVILLE, NY 11747-4501 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1994 VL 75 IS 8 BP 4208 EP 4213 DI 10.1063/1.356006 PG 6 WC Physics, Applied SC Physics GA NG577 UT WOS:A1994NG57700075 ER PT J AU KEYES, BM DUNLAVY, DJ AHRENKIEL, RK SHAW, G SUMMERS, GP TZAFARAS, N LENTZ, C AF KEYES, BM DUNLAVY, DJ AHRENKIEL, RK SHAW, G SUMMERS, GP TZAFARAS, N LENTZ, C TI TIME-RESOLVED PHOTOLUMINESCENCE OF UNDOPED INP SO JOURNAL OF APPLIED PHYSICS LA English DT Note ID SURFACE RECOMBINATION; SOLAR-CELLS; N-TYPE; GAAS AB Energy and time-resolved photoluminescence data have been obtained for nominally undoped (n 4.5 X 10(15) cm-3) bulk InP grown by the vertical-gradient freeze method. The data were taken as a function of temperature, from 80 to 290 K, and analyzed using a solution to the continuity equation. The resulting lifetime values range from 300 ns to 3.2 mus, and surface recombination velocities were fund to be on the order of 10(3) cm/s. The temperature dependence can be explained by assuming a radiatively limited recombination with a resulting B coefficient greater-than-or-equal-to 5.9 X 10(-11) cm3/s at 300 K. C1 USN,RES LAB,WASHINGTON,DC 20375. AT&T MICROELECTR LAB,READING,PA 19612. RP KEYES, BM (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 14 TC 8 Z9 8 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1994 VL 75 IS 8 BP 4249 EP 4251 DI 10.1063/1.355962 PG 3 WC Physics, Applied SC Physics GA NG577 UT WOS:A1994NG57700082 ER PT J AU ROSENWAKS, Y NOZIK, AJ YAVNEH, I AF ROSENWAKS, Y NOZIK, AJ YAVNEH, I TI THE EFFECT OF ELECTRIC-FIELDS ON TIME-RESOLVED PHOTOLUMINESCENCE SPECTRA IN SEMICONDUCTORS SO JOURNAL OF APPLIED PHYSICS LA English DT Note ID SURFACE; INTERFACES; INP AB We present a rigorous analysis of the effects of electric fields on time-resolved photoluminescence in semiconductors. The results show that the effect of the field alone on the photoluminescence decay can be distinguished from that of field-enhanced surface recombination if the carrier injection levels, the surface recombination velocity at zero field, and the band bending in the dark are within certain limits. When these experimental conditions are met it is possible to extract the recombination and/or transfer velocity of free carriers in the presence of electric fields. C1 TECHNION ISRAEL INST TECHNOL,DEPT COMP SCI,IL-32000 HAIFA,ISRAEL. RP ROSENWAKS, Y (reprint author), NATL RENEWABLE ENERGY LAB,GOLDEN,CO 80401, USA. NR 12 TC 9 Z9 9 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD APR 15 PY 1994 VL 75 IS 8 BP 4255 EP 4257 DI 10.1063/1.355964 PG 3 WC Physics, Applied SC Physics GA NG577 UT WOS:A1994NG57700084 ER PT J AU LARIMER, FW HARPEL, MR HARTMAN, FC AF LARIMER, FW HARPEL, MR HARTMAN, FC TI BETA-ELIMINATION OF PHOSPHATE FROM REACTION INTERMEDIATES BY SITE-DIRECTED MUTANTS OF RIBULOSE-BISPHOSPHATE CARBOXYLASE OXYGENASE SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID RIBULOSE-1,5-BISPHOSPHATE CARBOXYLASE; RIBULOSEBISPHOSPHATE CARBOXYLASE; RHODOSPIRILLUM-RUBRUM; ACTIVE-SITE; 1,5-BISPHOSPHATE CARBOXYLASE; TRIOSEPHOSPHATE ISOMERASE; CRYSTALLOGRAPHIC ANALYSIS; DIPHOSPHATE OXYGENASE; CRYSTAL-STRUCTURE; PYRUVATE-KINASE AB Five residues (Thr-53, Asn-54, Gly-370, Gly-393, and Gly-394) of Rhodospirillum rubrum ribulose-bisphosphate carboxylase/oxygenase are positioned to serve as hydrogen-bond donors for the C1 phosphate of ribulose bisphosphate and thereby constrain conformational flexibility of the initial enediol(ate) intermediate (Knight, S., Andersson, I., and Branden, C.-I. (1990) J. Mol. Biol. 215, 113-160). To study the functional contributions of the residues implicated in ribulose bisphosphate binding and intermediate stabilization, we have replaced them individually with alanine, either to remove the H-bonding group (T53A, N54A) or to introduce bulk (G370A, G393A, G394A). Consequences of substitutions include diminution of carboxylase activity (with a lesser impact on enolization activity), increase of K(m) (ribulose bisphosphate), and decrease of carboxylation: oxygenation specificity. During catalytic turnover of ribulose bisphosphate by several mutants, substantial amounts of the substrate are diverted to 1-deoxy-D-glycero-2,3-pentodiulose 5-phosphate, reflecting beta-elimination of phosphate from the enediol(ate) intermediate. This side product is not observed with wild-type enzyme, nor has it been reported with mutant enzymes characterized previously. Another consequence of disruption of the phosphate binding site is enhanced production of pyruvate, relative to wild-type enzyme, by some of the mutants due to decomposition of the aci-carbanion of 3-phosphoglycerate (the terminal intermediate). These data provide direct evidence that phosphate ligands stabilize conformations of intermediates that favor productive turnover and mitigate beta-elimination at two stages of overall catalysis. RP LARIMER, FW (reprint author), OAK RIDGE NATL LAB,DIV BIOL,PROT ENGN PROGRAM,OAK RIDGE,TN 37831, USA. NR 45 TC 28 Z9 28 U1 2 U2 2 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD APR 15 PY 1994 VL 269 IS 15 BP 11114 EP 11120 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA NF966 UT WOS:A1994NF96600025 PM 8157638 ER PT J AU RUEDENBERG, K SUN, JQ AF RUEDENBERG, K SUN, JQ TI GRADIENT FIELDS OF POTENTIAL-ENERGY SURFACES SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID QUADRATIC STEEPEST DESCENT; SADDLE POINTS; PATH; EXTREMALS; LOCATION; LINES AB While contour plots provide conceptual pictures of potential energy surfaces and exhibit their critical points, quantitative determinations of critical points and reaction paths as well as dynamical calculations require a knowledge of the gradient fields. The corresponding orthogonal trajectory maps are more complex than contour maps, but they provide additional insights. They are found to contain certain frequently occurring structural elements and these patterns are here examined. It is shown that many of them result from local confluences of orthogonal trajectory bundles with gradient extremals. The analysis leads to the distinction between eight different kinds of such gradient extremal channels. The most important ones are the streambeds and ridges, the former being typical conceptual prototypes of reaction channels, the latter being prototypes of reaction barriers. Gradient extremal channels emanate from second order critical points in the directions of all normal modes, but they do not necessarily follow along the entire reaction path of any one reaction. They can also exist unrelated to critical points. The conclusions are exemplified on a number of model potential energy surfaces. C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP RUEDENBERG, K (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 15 TC 29 Z9 29 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 15 PY 1994 VL 100 IS 8 BP 5836 EP 5848 DI 10.1063/1.467147 PG 13 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NF081 UT WOS:A1994NF08100044 ER PT J AU DUNPHY, JC MCINTYRE, BJ GOMEZ, J OGLETREE, DF SOMORJAI, GA SALMERON, MB AF DUNPHY, JC MCINTYRE, BJ GOMEZ, J OGLETREE, DF SOMORJAI, GA SALMERON, MB TI COADSORBATE INDUCED COMPRESSION OF SULFUR OVERLAYERS ON RE(0001) AND PT(111) BY CO SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID SINGLE-CRYSTAL SURFACES; CARBON-MONOXIDE; ADSORPTION; TRANSFORMATION; SYSTEM AB Low coverages of sulfur chemisorbed on the rhenium(0001) and platinum(111) surfaces were studied in UHV by scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED). On both of these surfaces of triangular symmetry the lowest coverage (almost-equal-to 0.25 monolayers) ordered structure is p(2 x 2). Exposure of this ordered sulfur overlayer on either surface to low pressures (10(-9) Torr) of CO induces compression of the sulfur layer to a structure associated with a higher local coverage and CO chemisorbs in the holes created in the sulfur layer. The reordering was observed by both a change in the LEED pattern and by real space STM imaging of the surface. On the Re surface the new overlayer has (3 square-root 3 x 3 square-root)R30-degrees symmetry, while on the Pt surface it has (square-root 3 x square-root 3)R30-degrees symmetry. There was no increase in the amount of sulfur on the surface during this reordering. On both surfaces the overlayers could be returned to the original p(2 x 2) by annealing for several seconds at 600-degrees-C, during which CO desorbs and sulfur atoms reoccupy the vacant metal sites. This phenomenon of the compression of atoms in a strongly chemisorbed layer upon coadsorption of another molecule provides a mechanism for carrying out catalytic reactions on metal surfaces that are covered with strongly chemisorbed layers that do not participate in the reaction. C1 UNIV CALIF BERKELEY,DEPT CHEM,BERKELEY,CA 94720. UNIV AUTONOMA MADRID,DEPT FIS MAT CONDENSADA,MADRID 34,SPAIN. UNIV CALIF BERKELEY,DEPT PHYS,BERKELEY,CA 94720. RP DUNPHY, JC (reprint author), LAWRENCE BERKELEY LAB,CTR ADV MAT,DIV MAT SCI,BERKELEY,CA 94720, USA. RI Gomez-Herrero, Julio/B-6094-2013; Ogletree, D Frank/D-9833-2016 OI Gomez-Herrero, Julio/0000-0001-8583-8061; Ogletree, D Frank/0000-0002-8159-0182 NR 20 TC 30 Z9 31 U1 0 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 15 PY 1994 VL 100 IS 8 BP 6092 EP 6097 DI 10.1063/1.467121 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NF081 UT WOS:A1994NF08100072 ER PT J AU RUEDENBERG, K SUN, JQ AF RUEDENBERG, K SUN, JQ TI QUADRATIC STEEPEST DESCENT ON POTENTIAL-ENERGY SURFACES .4. ADAPTATION TO SINGULAR HESSIANS SO JOURNAL OF CHEMICAL PHYSICS LA English DT Note C1 IOWA STATE UNIV SCI & TECHNOL,DEPT CHEM,AMES,IA 50011. RP RUEDENBERG, K (reprint author), IOWA STATE UNIV SCI & TECHNOL,US DOE,AMES LAB,AMES,IA 50011, USA. NR 3 TC 12 Z9 12 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 15 PY 1994 VL 100 IS 8 BP 6101 EP 6101 DI 10.1063/1.467123 PG 1 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA NF081 UT WOS:A1994NF08100074 ER PT J AU WALLACE, DWR BEINING, P PUTZKA, A AF WALLACE, DWR BEINING, P PUTZKA, A TI CARBON-TETRACHLORIDE AND CHLOROFLUOROCARBONS IN THE SOUTH-ATLANTIC OCEAN, 19-DEGREES-S SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID ATMOSPHERIC LIFETIME EXPERIMENT; WESTERN BOUNDARY CURRENT; LAW CONSTANTS; WATER; CHLOROFLUOROMETHANES; TRACERS; CIRCULATION; SEAWATER; CCL2F2; CCL3F AB Exploratory measurements of a suite of anthropogenic halocarbon compounds (CCl4, CCl2FCClF2 (CFC-113), CH3CCl3, CCl3F (CFC-11)) were made using a new analytical technique on RV Meteor cruise 15 along 19-degrees-S (World Ocean Circulation Experiment (WOCE) Line A9)) in the Atlantic Ocean during February-March 1991. A separate analytical system was used to determine CCl2F2 (CFC-12) and CCl3F (CFC-11). A limited number of CFC-113 profiles indicated that it was undetectable below 400-500 m. The CCl4 data indicate that the entire Brazil Basin contains readily measurable levels of CCl4 (>0.05 pmol kg-1), whereas the deep Angola Basin contains very low levels (less-than-or-equal-to 0.02 pmol kg-1). Slightly higher levels were found close to the bottom in the deep Angola Basin: possibly an anthropogenic signature. In contrast, most of the deep Brazil Basin and all of the deep Angola Basin (> 1000 m) had undetectable levels of CFC-11, CFC-12, and CFC-113. Preindustrial levels of CCl4 in the atmosphere were therefore negligible (atmospheric mixing ratio <0.1 pptv). CCl4/CFC-11 ratios are used to estimate apparent ages and dilution factors for the North Atlantic Deep te an Antarctic Bottom Water. Whereas CCl4/CFC-11/CFC-12 levels are internally consistent in deep waters, suggesting near-conservative behavior, there is evidence for very rapid removal of CCl4 in the thermocline. Removal rates suggest that in addition to neutral hydrolysis, some other loss pathway must be involved. C1 UNIV BREMEN,W-2800 BREMEN,GERMANY. RP WALLACE, DWR (reprint author), BROOKHAVEN NATL LAB,DEPT APPL SCI,UPTON,NY 11973, USA. NR 43 TC 58 Z9 58 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD APR 15 PY 1994 VL 99 IS C4 BP 7803 EP 7819 DI 10.1029/94JC00031 PG 17 WC Oceanography SC Oceanography GA NG710 UT WOS:A1994NG71000036 ER PT J AU DUKOWICZ, JK SMITH, RD AF DUKOWICZ, JK SMITH, RD TI IMPLICIT FREE-SURFACE METHOD FOR THE BRYAN-COX-SEMTNER OCEAN MODEL SO JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS LA English DT Article ID CIRCULATION AB The surface pressure reformulation of the Bryan-Cox-Semtner global ocean model, which we developed recently, has been further improved by eliminating the rigid-lid approximation in favor of an implicit free-surface method for the barotropic mode. This retains the advantages of the surface pressure formulation and in addition (1) substantially improves the computational efficiency of the barotropic mode; (2) computes surface height directly, allowing comparison with and assimilation of altimetry data (with a rigid-lid case the surface height is accurately computed only in the limit of a steady state); (3) improves accuracy in the computation of long-wavelength Rossby waves and includes the effects of long-wavelength surface gravity waves; (4) provides robustness by selectively damping computational modes; (5) simplifies satisfying global energetic balances required for energetic consistency; and (6) alleviates ''checkerboarding'' in the surface height or pressure fields. A variable thickness top-layer model is developed to account for the free surface, and a generalized form of implicit time discretization of the barotropic equations is introduced. This discretization is analyzed in detail from the point of view of accuracy, stability, and damping properties, and certain cases are selected for their advantageous properties. The performance of the method is demonstrated on the Connection Machine, CM-200, and the results of numerical simulations are compared using the stream function, rigid-lid surface pressure, and free-surface formulations. RP DUKOWICZ, JK (reprint author), LOS ALAMOS NATL LAB,DIV THEORET,GRP T-3,MS B216,LOS ALAMOS,NM 87545, USA. NR 19 TC 264 Z9 266 U1 0 U2 12 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 SN 0148-0227 J9 J GEOPHYS RES-OCEANS JI J. Geophys. Res.-Oceans PD APR 15 PY 1994 VL 99 IS C4 BP 7991 EP 8014 DI 10.1029/93JC03455 PG 24 WC Oceanography SC Oceanography GA NG710 UT WOS:A1994NG71000051 ER PT J AU LEE, JC SUBRAMANIAN, KN KIM, Y AF LEE, JC SUBRAMANIAN, KN KIM, Y TI THE INTERFACE IN AL2O3 PARTICULATE-REINFORCED ALUMINUM-ALLOY COMPOSITE AND ITS ROLE ON THE TENSILE PROPERTIES SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID METAL MATRIX COMPOSITES; CAST ALUMINUM; FABRICATION; FIBER; BEHAVIOR; PHASE AB The interface characterization of the aluminium alloy reinforced with Al2O3 particulates ((Al2O3)p/Al composite) was performed using X-ray diffractometry and energy dispersive X-ray spectroscopy. A layer of MgAl2O4 single crystals was observed at the (Al2O3)p/Al interface in the as-received extruded composites. Such MgAl2O4 crystals formed at the surface of (Al2O3)p are believed to grow by consuming a certain amount of (Al2O3)p. Upon loading, interfacial debonding was observed to occur at the boundary between MgAl2O4 and the aluminium alloy, or along the MgAl2O4 layer itself. These experimental observations are correlated with the tensile properties of such composites. C1 US DOE,AMES LAB,AMES,IA 50011. RP LEE, JC (reprint author), MICHIGAN STATE UNIV,DEPT MAT SCI & MECH,E LANSING,MI 48823, USA. NR 25 TC 28 Z9 29 U1 0 U2 1 PU CHAPMAN HALL LTD PI LONDON PA 2-6 BOUNDARY ROW, LONDON, ENGLAND SE1 8HN SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD APR 15 PY 1994 VL 29 IS 8 BP 1983 EP 1990 DI 10.1007/BF01154671 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA NJ064 UT WOS:A1994NJ06400001 ER EF