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Profiling and Mapping of Advanced Materials Using Spatially Resolved Raman Spectroscopy

Description: We have developed a technique to profile important physical and chemical properties of materials based upon simultaneous acquisition of Raman spectra along a laser illumination line, coupled with extensive and rapid spectral analysis to extract the desired information. The technique uses a two-dimensional spectroscopic detector and, in contrast to Hadamard techniques, sample movement in one dimension that allows all collected light to be detected. Property maps comprised of the analysis results… more
Date: August 1, 1991
Creator: Ager, Joel; Veirs, D. K.; Lee, H. Q. & Rosenblatt, G. M.
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Partner: UNT Libraries Government Documents Department
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Array analysis of regional Pn and Pg wavefields from the Nevada Test Site

Description: Small-aperture high-frequency seismic arrays with dimensions of a few kilometers or less, can improve our ability to seismically monitor compliance with a low-yield Threshold Test Ban Treaty. This work studies the characteristics and effectiveness of array processing of the regional Pn and Pg wavefields generated by underground nuclear explosions at the Nevada Test Site. Waveform data from the explosion HARDIN (m{sub b} = 5.5) is recorded at a temporary 12-element, 3-component, 1.5 km-aperture … more
Date: June 1, 1991
Creator: Leonard, M.A. (California Univ., Berkeley, CA (United States). Dept. of Geology and Geophysics Lawrence Berkeley Lab., CA (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Studies of Coupled Chemical and Catalytic Coal Conversion Methods

Description: When an arene is coordinated to Cr(CO){sub 3}, profound changes in its reactivity occur. Ring and benzylic hydrogen atoms exhibit enhanced acidity, and typical arene reactions such as electrophilic aromatic substitutions are quenched. In contrast, the ring carbon atoms are activated toward attack by nucleophiles. These changes in reactivity are manifestations of the forceful electron withdrawing nature of the Cr(CO){sub 3} component, and of the ability of this group to stabilize charged interme… more
Date: January 1, 1991
Creator: Stock, L. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photon stimulated desorption of neutral species from aluminum

Description: Photon Simulated Desorption of neutral species (PSD) is the major dynamic gas load in electron synchrotron light source. In the National Synchrotron Light Source, PSD presented initial machine commissioning difficulty. Sensitivity to surface contamination on PSD had been experienced during an incident of Fomblin Oil contamination. U10B-Photon Stimulated Desorption Experimental Station is constructed to investigate: (1) the degree of the contribution to the photon stimulated desorption (PSD) fro… more
Date: January 1, 1991
Creator: Chou, T.S.
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Partner: UNT Libraries Government Documents Department
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Jets in CDF

Description: In the 1988/89 Tevatron Collider run the CDF experiment collected 4.0 {plus minus} 0.3 pb{sup {minus}1} of proton-antiproton interactions at a center-of-mass collision energy currently available in the laboratory and gives us a unique opportunity for studying Quantum Chromodymanics (QCD) processes at the highest available energies. We report results from various QCD studies performed with this data. 11 refs., 8 figs.
Date: July 1, 1991
Creator: Buckley-Geer, E. (Rutgers--the State Univ., New Brunswick, NJ (United States))
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Partner: UNT Libraries Government Documents Department
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Picosecond infrared study of carbonmonoxy cytochrome c oxidase: Ligand transfer dynamics and binding orientations

Description: Cytochrome c oxidase (CcO), an enzyme which catalyzes the reduction of dioxygen to water in the terminal step of the respiratory chain, combines several fundamental chemical processes in performing its function. The coordination chemistry and ligation dynamics of the cytochrome {alpha}{sub 3}-Cu{sub B} site, where O{sub 2} and other small molecules such as CO, NO and isocyanates can bind, are essential to the function of the enzyme. Recent time-resolved infrared (TRIR) and visible absorption me… more
Date: January 1, 1991
Creator: Peterson, K.A.; Stoutland, P.O.; Dyer, R.B. & Woodruff, W.H.
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Partner: UNT Libraries Government Documents Department
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WIPP/SRL in-situ tests: MIIT program--The effects of metal package components

Description: The Materials Interface Interactions Tests or MIIT is the largest in-situ testing program in progress, involving burial of many simulated nuclear waste systems and accompanying package components. In MIIT, waste glass samples were fabricated into the shape of pineapple slices', polished on one side. Proposed package components were also made into a similar configuration and the various glasses, metals, and geologic samples were than stacked onto heater elements within Teflon assemblies. This pr… more
Date: January 1, 1991
Creator: Covington, J.A. (Clemson Univ., SC (United States)); Wicks, G.G. (Westinghouse Savannah River Co., Aiken, SC (United States)) & Molecke, M.A. (Sandia National Labs., Albuquerque, NM (United States))
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Partner: UNT Libraries Government Documents Department
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Vibrational spectroscopy of shock-compressed liquid CO

Description: Single-pulse, multiplex, coherent anti-Stokes Raman spectroscopy (CARS) was used to observe the vibrational spectra of liquid CO shock compressed to several pressures and temperatures up to 9.9 GPa and 2010 K. The experimental spectra were compared to synthetic spectra calculated using a semiclassical model for CARS intensities and estimated vibrational frequencies, peak Raman susceptibilities and Raman line widths. A comparison of these data with result in the isoelectronic and materially very… more
Date: January 1, 1991
Creator: Moore, D. S.; Schmidt, S. C.; Shaw, M. S. & Johnson, J. D.
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Partner: UNT Libraries Government Documents Department
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QCD tests at CDF

Description: Recent analysis of jet data taken at the Fermilab Tevatron Collider at {radical}S = 1.8 Tev are presented. Inclusive jet, dijet, trijet and direct photon measurements are compared to QCD parton level calculations, at orders {alpha}{sub s}{sup 3} or {alpha}{sub s}{sup 2}. The large total transverse energy events are well described by the Herwig shower Montecarlo. 19 refs., 20 figs., 1 tab.
Date: May 1, 1991
Creator: Giannetti, P. (Istituto Nazionale di Fisica Nucleare, Pisa (Italy))
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Partner: UNT Libraries Government Documents Department
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NMR imaging: A chemical' microscope for coal analysis

Description: This paper presents a new three-dimensional (3-D) nuclear magnetic resonance (NMR) imaging technique for spatially mapping proton distributions in whole coals and solvent-swollen coal samples. The technique is based on a 3-D back-projection protocol for data acquisition, and a reconstruction technique based on 3-D Radon transform inversion. In principle, the 3-D methodology provides higher spatial resolution of solid materials than is possible with conventional slice-selection protocols. The ap… more
Date: January 1, 1991
Creator: French, D.C.; Dieckman, S.L.; Gopalsami, N. & Botto, R.E.
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Partner: UNT Libraries Government Documents Department
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Prediction of thermodynamic properties of coal derivatives

Description: The purpose of this research program is to understand and model the effect of the different intermolecular forces on the thermodynamic properties of systems containing pure compounds and mixtures. The compounds under consideration vary considerably in size, shape and energy. Therefore in order to develop a theory capable of describing accurately the thermodynamic properties and phase behavior of such systems over a wide range of temperature and pressure, one has to take into account explicitly … more
Date: October 1, 1991
Creator: Donohue, M.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The ligand shuttle'' reactions of cytochrome oxidase: Spectroscopic evidence, dynamics, and functional significance

Description: Time-resolved electronic absorption, infrared, resonance Raman, and magnetic circular dichroism spectroscopies are applied to characterization of the intermediate which is formed within 20 ps after photodissociation of CO from cytochrome a{sub 3} of reduced cytochrome oxidase. This intermediate decays with the same halflife (ca. 1 {mu}s) as the post-photodissociation Cu{sub B}{sup +} -CO species previously observed by time-resolved infrared. The transient UV-Vis spectra, kinetics, infrared, and… more
Date: January 1, 1991
Creator: Woodruff, W. H.; Dyer, R. B.; Peterson, K. A.; Stoutland, P. O.; Bagley, K. A. (Los Alamos National Lab., NM (USA)); Einarsdottir, O. et al.
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Partner: UNT Libraries Government Documents Department
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The performance of a single-crystal BGO annulus as a Compton- suppression detector

Description: We have tested a single-crystal bismuth-germanate annulus in conjunction with a high-purity germanium detector as a Compton-suppression spectrometer, and have measured gamma-ray energies of up to 6.13 MeV. 1 ref., 9 figs., 2 tabs.
Date: January 1, 1991
Creator: Ussery, L.E. (Los Alamos National Lab., NM (United States)) & Matthews, S.K. (George Washington Univ., Washington, DC (United States))
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Partner: UNT Libraries Government Documents Department
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Activation analyses for different fusion structural alloys

Description: The leading candidate structural materials, viz., the vanadium alloys, the nickel or the manganese stabilized austenitic steels, and the ferritic steels, are analysed in terms of their induced activation in the TPSS fusion power reactor. The TPSS reactor has 1950 MW fusion power and inboard and outboard average neutron wall loading of 3.75 and 5.35 MW/m{sup 2} respectively. The results shows that, after one year of continuous operation, the vanadium alloys have the least radioactivity at reacto… more
Date: January 1, 1991
Creator: Attaya, H. & Smith, D.
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Partner: UNT Libraries Government Documents Department
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Evidence for. rho. sub 1 (1600) from the decay J/. psi. yields. pi. sup minus. pi. sup +. pi. sup 0

Description: Data from MARK 3 on the decay J/{psi} {yields} {pi}{sup {minus}}{pi}{sup +}{pi}{sup 0} are described in terms of amplitudes representing the sequential two-body decay processes J/{psi} {yields} {rho}{pi}, {rho}{yields}{pi}{pi}. It is found that a complete description requires contributions from excited J{sup PC} = 1{sup --} states in addition to the dominant contribution form the {rho}(770). The characteristics of these additional states are discussed. 11 refs., 6 figs.
Date: October 1, 1991
Creator: Chen, Liang-Ping (Vanderbilt Univ., Nashville, TN (United States)) & Dunwoodie, W. (Stanford Linear Accelerator Center, Menlo Park, CA (United States))
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Partner: UNT Libraries Government Documents Department
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Synthesis of a C sub 60 -para-xylylene copolymer

Description: The preparation and purification of macroscopic quantities of buckminsterfullerenes of buckyballs has ignited an explosion of research into their physical and chemical properties, and a variety of strategies for preparing new fullerene-based materials. Free radical synthesis is an appealing approach for forming polymeric fullerene materials. We report a polymeric fullerene material prepared by reacting pure C{sub 60} with xylylene from the thermolysis of paracyclophane. Addition of xylylene to … more
Date: January 1, 1991
Creator: Loy, Douglas A. & Assink, Roger A.
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Partner: UNT Libraries Government Documents Department
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Comparison of explicit calculations for n = 3 to 8 dielectronic satellites of the FeXXV K. alpha. resonance line with experimental data from the Tokamak Fusion Test Reactor

Description: Dielectronic satellite spectra of the FeXXV K{alpha} resonance line observed from the Tokamak Fusion Test Reactor (TFTR) plasmas have been compared with recent explicit calculations for the n = 3 to 8 dielectronic satellites as well as the earlier theoretical predictions, which were based on the 1/n{sup 3} scaling law for n > 4 satellites. The analysis has been performed by least-squares fits of synthetic spectra to the experimental data. The synthetic spectra constructed from both theories are… more
Date: December 1, 1991
Creator: Decaux, V.; Bitter, M.; Hsuan, H.; Hill, K.W.; Von Goeler, S.; Park, H. (Princeton Univ., NJ (United States). Plasma Physics Lab.) et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Infrared Synchrotron Radiation instrumentation and applications

Description: Infrared Synchrotron Radiation (IRSR) is a blossoming field which has three working beamlines, U4IR at the National Synchrotron Light Source, Brookhaven National Laboratory, USA, and two at the Institute of Molecular Sciences in Okasaki, Japan with extensive research projects. There are also several new beamlines in the planning and development stages, both in the United States and abroad. IRSR offers a unique way to access the far infrared (30 {mu} to approx 1 mm) which is a notoriously diffic… more
Date: January 1, 1991
Creator: Hirschmugl, C. (Yale Univ., New Haven, CT (United States). Dept. of Applied Physics)
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Partner: UNT Libraries Government Documents Department
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WZ Sge: An accretion test case

Description: WZ Sge provides us with an excellent test for numerical codes trying to reproduce the heating and cooling of a white dwarf due to accreted material. This is because of both the many observed quantities of this binary and its long quiescent state. However, a large discrepancy appears between the observed white dwarf's cooling curve and calculated cooling curve from the deduced accreted mass. Possible causes for this discrepancy are discussed.
Date: January 1, 1991
Creator: Sparks, W. M.; Sion, E. M.; Starrfield, S. G. & Austin, S.
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Partner: UNT Libraries Government Documents Department
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Results from AGS E845: K sub L sup 0 yields. pi. sup 0 e sup + e sup minus , e sup + e sup minus. gamma. , e sup + e sup minus e sup + e sup minus

Description: Results from AGS experiment 845 are reviewed. The data was collected during 1989. Final results on K{sub L}{sup 0} {yields} {pi}{sup 0}e{sup +}e{sup {minus}} and e{sup +}e{sup {minus}} {gamma} are described. Preliminary results on e{sup +}e{sup {minus}}{gamma}{gamma} and e{sup +}e{sup {minus}}e{sup +}e{sup {minus}} are discussed. 10 refs., 5 figs.
Date: January 1, 1991
Creator: Morse, W.M.; Leipuner, L.B.; Larsen, R.C.; Jastrzembski, E. (Brookhaven National Lab., Upton, NY (USA)); Adair, R.K.; Greenlee, H.B. et al.
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Partner: UNT Libraries Government Documents Department
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Spectroscopy of transient neutral species via negative ion photoelectron spectroscopy

Description: Negative ion photoelectron spectroscopy has been used to study two types of transient neutral species: bound free radicals (NO{sub 2} and NO{sub 3}) and unstable neutral species ((IHI) and (FH{sub 2})). The negative ion time-of-flight photoelectron spectrometer used for these experiments is described in detail.
Date: December 1, 1991
Creator: Weaver, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simulations of a spectral gamma-ray logging tool response to a surface source distribution on the borehole wall

Description: We have developed Monte Carlo and discrete ordinates simulation models for the large-detector spectral gamma-ray (SGR) logging tool in use at the Nevada Test Site. Application of the simulation models produced spectra for source layers on the borehole wall, either from potassium-bearing mudcakes or from plate-out of radon daughter products. Simulations show that the shape and magnitude of gamma-ray spectra from sources distributed on the borehole wall depend on radial position with in the air-f… more
Date: January 1, 1991
Creator: Wilson, R.D. (Highland Scientific Ltd., Ashland, OR (United States)) & Conaway, J.G. (Los Alamos National Lab., NM (United States))
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Partner: UNT Libraries Government Documents Department
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The neutral kaon program at Fermilab and recent E731 results

Description: Currently, Fermilab has a long-range program in neutral kaon physics which covers a wide variety of physics topics. In this report, I will be discussing the latest results from experiment E731 on the radiative decay of neutral kaons K{sub L,S} {yields} {pi}{sup +}{pi}{sup {minus}} {gamma}. These results include the first measurement of two new CP violation parameters: {eta}{sub +} {sub {minus}}{gamma} = (2.60{plus minus}0.54{plus minus}0.21) {center dot} 10{sup {minus}3}, and {phi}{sub +}{sub {… more
Date: September 1, 1991
Creator: Ramberg, E.J.
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Partner: UNT Libraries Government Documents Department
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Diagnostic studies of YBa sub 2 Cu sub 3 O sub 7-. delta. laser ablation

Description: The use of a variety of diagnostics can offer significant insight into the mechanisms of laser ablation and film growth. It seems clear that under conditions of optimum film growth that significant collisional processes occur both within the laser-desorbed plume, and between the plume and the processing gas. These collisional processes are responsible for the macroscopic characteristics of the plume, including velocity and spatial distributions, the ratio of ions and particles to neutral atoms … more
Date: January 1, 1991
Creator: Nogar, N. S.; Dye, R. C.; Foltyn, S. R.; Muenchausen, R. E.; Wu, X. D. & Estler, R. C.
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Partner: UNT Libraries Government Documents Department
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