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Electron energy distributions, vibrational population distributions, and negative-ion concentrations in hydrogen discharges

Description: We consider the negative ion concentrations in hydrogen discharges caused by electron excitation and dissociative attachment processes. The principal formation and destruction processes are discussed for electron densities in the range 10/sup 8/ to 10/sup 13/ electrons cm/sup -3/. Expressions are developed for calculating the high energy portion of the electron energy distribution in the discharge; using these energy distributions the electron excitation rates are evaluated. At low densities, t… more
Date: June 28, 1982
Creator: Hiskes, J.R. & Karo, A.M.
Partner: UNT Libraries Government Documents Department
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Heats of Formation of Triplet Ethylene, Ethylidene, and Acetylene

Description: Heats of formation of the lowest triplet state of ethylene and the ground triplet state of ethylidene have been predicted by high level electronic structure calculations. Total atomization energies obtained from coupled-cluster CCSD(T) energies extrapolated to the complete basis set limit using correlation consistent basis sets (CBS), plus additional corrections predict the following heats of formation in kcal/mol: Delta H0f(C2H4,3A1) = 80.1 at 0 K and 78.5 at 298 K, and Delta H0f(CH3CH,3A&quot… more
Date: June 28, 2007
Creator: Nguyen, M. T.; Matus, M. H.; Lester, W. A. Jr. & Dixon, David A.
Partner: UNT Libraries Government Documents Department
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Low-level detection and quantification of Plutonium(III, IV, V,and VI) using a liquid core waveguide

Description: Understanding the aqueous chemistry of plutonium, in particular in environmental conditions, is often complicated by plutonium's complex redox chemistry. Because plutonium possesses four oxidation states, all of which can coexist in solution, a reliable method for the identification of these oxidation states is needed. The identification of plutonium oxidation states at low levels in aqueous solution is often accomplished through an indirect determination using series of liquid-liquid extractio… more
Date: June 28, 2003
Creator: Wilson, Richard E.; Hu, Yung-Jin & Nitsche, Heino
Partner: UNT Libraries Government Documents Department
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Direct observation of photoinduced bent nitrosyl excited-state complexes

Description: Ground state structures with side-on nitrosyl ({eta}{sup 2}-NO) and isonitrosyl (ON) ligands have been observed in a variety of transition-metal complexes. In contrast, excited state structures with bent-NO ligands have been proposed for years but never directly observed. Here we use picosecond time-resolved infrared spectroscopy and density functional theory (DFT) modeling to study the photochemistry of Co(CO){sub 3}(NO), a model transition-metal-NO compound. Surprisingly, we have observed no … more
Date: June 28, 2008
Creator: Sawyer, Karma R.; Steele, Ryan P.; Glascoe, Elizabeth A.; Cahoon, James F.; Schlegel, Jacob P.; Head-Gordon, Martin et al.
Partner: UNT Libraries Government Documents Department
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Transparent Laser Ceramics at Lawrence Livermore National Laboratory (LLNL)

Description: LLNL has been using the largest transparent laser ceramics for the last two years in the solid-state heat capacity laser (SSHCL). The lab is very interested in extending the use of transparent ceramics to other laser applications. In this talk we will discuss work at the laboratory aimed at better understanding the sintering and the criteria needed for good ceramic transparency, the application of transparent ceramics in the SSHCL laser and possible new applications of tailored ceramics.
Date: June 28, 2007
Creator: Soules, T
Partner: UNT Libraries Government Documents Department
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Electronic Properties of LiFePO4 and Li doped LiFePO4

Description: The potential use of different iron phosphates as cathodematerials in lithium-ion batteries has recently been investigated.1 Oneof the promising candidates is LiFePO4. This compound has severaladvantages in comparison to the state-of-the-art cathode material incommercial rechargeable lithium batteries. Firstly, it has a hightheoretical capacity (170 mAh/g). Secondly, it occurs as mineraltriphylite in nature and is inexpensive, thermally stable, non-toxic andnon-hygroscopic. However, its low ele… more
Date: June 28, 2005
Creator: Zhuang, G.V.; Allen, J.L.; Ross, P.N.; Guo, J.-H. & Jow, T.R.
Partner: UNT Libraries Government Documents Department
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Self-induced rainout from a nuclear weapon

Description: The conclusions we have reached are that rainout of fresh radioactive debris occurred at Hiroshima and Nagasaki, that this precipitation was initiated either by the weapon itself or by the ensuing fires or by both, and that self-induced rainout can occur and deposit sufficient amounts of radioactivity on the ground to pose a significant collateral damage hazard.
Date: June 28, 1979
Creator: Molenkamp, C.R.
Partner: UNT Libraries Government Documents Department
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Catalytic studies on a novel synthesis of methanol

Description: Catalytic studies on a new method for methanol synthesis from CO and H{sub 2} in a slurry reactor are described. This reaction proceeds through the carbonylation of methanol to methyl formate in the liquid phase followed by hydrogenolysis of methyl formate to two molecules of methanol; the net result is the reaction of CO with H{sub 2} to give methanol. Moderate temperatures and pressures (100--160{degrees}C, 50--65 atm) are used. Reaction rates using mixed catalysts comprised of an alkali meth… more
Date: June 28, 1991
Creator: Palekar, V.M.; Tierney, J.W. & Wender, I.
Partner: UNT Libraries Government Documents Department
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Subsurface probing

Description: Imaging techniques that can be used to translate seismic and electromagnetic wave signals into visual representation are briefly discussed. The application of these techniques is illustrated on the example of determining the subsurface structure of a proposed power plant. Imaging makes the wave signals intelligible to the non-geologists. R and D work needed in this area are tabulated. (JSR)
Date: June 28, 1978
Creator: Lytle, R.J.
Partner: UNT Libraries Government Documents Department
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Tumulus Disposal Demonstration Facility for the Oak Ridge Reservation

Description: This disposal concept is based on the Tumulus design developed by the French at the La Manche facility. Waste units are stacked above-grade on a concrete pad. The facility currently under development at the Oak Ridge National Laboratory (ORNL) involves sealing waste in concrete vaults, placing the vaults on a grade level concrete pad, and covering the pad and vaults with a soil cover after vault emplacement is complete. Emplacement is expected to continue until the facility exhausts its approxi… more
Date: June 28, 1987
Creator: Clapp, R.B. & van Hoesen, S.D.
Partner: UNT Libraries Government Documents Department
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Electrooptic deflector design considerations or use in the crystal streak camera

Description: Figure-of-merit equations for material selection and detailed design equations have been developed to aid in the design of a linear electrooptic deflector element for use in a 10-ps streak camera. The figure of merit indicates that BaTiO/sub 3/, KTN, and ammonium oxalate (AMO) are suitable materials. Possible deflector designs, including that of a current AMO prototype development program, are discussed. Quadratic (Kerr-effect) operation and materials are discussed along with the possibility fo… more
Date: June 28, 1978
Creator: Thomas, S.W.
Partner: UNT Libraries Government Documents Department
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Non-Fermi Liquid scaling in UPd{sub x}Cu{sub 5-x}(x = 1,1.5)

Description: We have determined the inelastic magnetic response S({omega}) of UPd{sub x}cu{sub 5{minus}x} (X=1,1.5) for temperatures from 0.3 to 300 K and energies between 05 and 400 meV using the neutron time of flight technique. S({omega}) is virtually identical in the two compound, displaying marginal Fermi Liquid scaling over the entire range of temperatures, as well as scale invariant energetics.
Date: June 28, 1994
Creator: Aronson, M. C.; Osborn, R.; Robinson, R. A.; Lynn, J. W.; Chau, R.; Seaman, C. L. et al.
Partner: UNT Libraries Government Documents Department
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Hydrodynamic Modeling of a Multi-Pulse X-Ray Converter Target for DARHT - II

Description: In phase two of the Dual-Axis Radiographic Hydrodynamic Test facility (DARHT-II), four electron beam pulses of variable pulse length strike an X-ray converter target to produce time-resolved X-ray image. An important requirement for the converter target is to minimize the hydrodynamic expansion of the converter material so that there is enough material to generate the required X-ray dose for all four pulses. Minimizing the hydrodynamic expansion is also important from the standpoint of beam tra… more
Date: June 28, 2001
Creator: Ho, D. D. M.; Chen, Y. J.; Harte, J. & Young, D.
Partner: UNT Libraries Government Documents Department
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State-of-the-art Monte Carlo 1988

Description: Particle transport calculations in highly dimensional and physically complex geometries, such as detector calibration, radiation shielding, space reactors, and oil-well logging, generally require Monte Carlo transport techniques. Monte Carlo particle transport can be performed on a variety of computers ranging from APOLLOs to VAXs. Some of the hardware and software developments, which now permit Monte Carlo methods to be routinely used, are reviewed in this paper. The development of inexpensive… more
Date: June 28, 1988
Creator: Soran, P. D.
Partner: UNT Libraries Government Documents Department
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Slowly Varying Dilaton Cosmologies and Their Field Theory Duals

Description: We consider a deformation of the AdS{sub 5} x S{sup 5} solution of IIB supergravity obtained by taking the boundary value of the dilaton to be time dependent. The time dependence is taken to be slowly varying on the AdS scale thereby introducing a small parameter {epsilon}. The boundary dilaton has a profile which asymptotes to a constant in the far past and future and attains a minimum value at intermediate times. We construct the sugra solution to first non-trivial order in {epsilon}, and fin… more
Date: June 28, 2011
Creator: Awad, Adel; Das, Sumit R.; Ghosh, Archisman; Oh, Jae-Hyuk & Trivedi, Sandip P.
Partner: UNT Libraries Government Documents Department
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Stable Non-Supersymmetric Throats in String Theory

Description: We construct a large class of non-supersymmetric AdS-like throat geometries in string theory by taking non-supersymmetric orbifolds of supersymmetric backgrounds. The scale of SUSY breaking is the AdS radius, and the dual field theory has explicitly broken supersymmetry. The large hierarchy of energy scales in these geometries is stable. We establish this by showing that the dual gauge theories do not have any relevant operators which are singlets under the global symmetries. When the geometrie… more
Date: June 28, 2011
Creator: Kachru, Shamit; Simic, Dusan; /Stanford U., ITP /SLAC /Santa Barbara, KITP; Trivedi, Sandip P. & /Tata Inst. /Stanford U., ITP /SLAC
Partner: UNT Libraries Government Documents Department
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Lifetime Measurement of the 2{sup +}{sub 1} state in {sup 20}C

Description: Establishing how and when large N/Z values require modified or new theoretical tools is a major quest in nuclear physics. Here we report the first measurement of the lifetime of the 2{sup +}{sub 1} state in the near-dripline nucleus {sup 20}C. The deduced value of {tau}{sub #28;2{sup +}{sub 1}} = 9.8 ± 2.8(stat){sup +0.5}{sub −1.1}(syst) ps gives a reduced transition probability of B(E2;2{sup +}{sub 1}{yields}0{sup +}{sub g.s.}) = 7.5{sup +3.0}{sub −1.7}(stat){sup +1.0}{sub −0.4}(syst) e{sup 2}… more
Date: June 28, 2011
Creator: Petri, Marina-Kalliopi; Fallon, Paul; Macchiavelli, Augusto; Paschalis, Stephanos; Starosta, Krzysztof; Baugher, Travis et al.
Partner: UNT Libraries Government Documents Department
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Productivity Techniques and Quality Aspects in the Criticality Safety Evaluation of Y-12 Type-B Fissile Material Packages

Description: The inventory of certified Type-B fissile material packages consists of ten performance-based packages for offsite transportation purposes, serving transportation programs at the Y-12 National Security Complex. The containment vessels range from 5 to 19 in. in diameter and from 17 to 58 in. in height. The drum assembly external to the containment vessel ranges from 18 to 34 in. in diameter and from 26 to 71 in. in height. The weight of the packaging (drum assembly and containment vessel) ranges… more
Date: June 28, 2011
Creator: DeClue, J. F.
Partner: UNT Libraries Government Documents Department
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Power Supply Changes for NSTX Resistive Wall Mode Coils

Description: The National Spherical Torus Experiment (NSTX) has been designed and installed in the existing facilities at Princeton Plasma Physics Laboratory (PPPL). Most of the hardware, plant facilities, auxiliary sub-systems, and power systems originally used for the Tokamak Fusion Test Reactor (TFTR) have been used with suitable modifications to reflect NSTX needs. Prior to 2004, the NSTX power system was feeding twelve (12) circuits in the machine. In 2004 the Resistive Wall Mode (RWM) Coils were insta… more
Date: June 28, 2013
Creator: Ramakrishnan, S S.
Partner: UNT Libraries Government Documents Department
open access

The History of X-ray Free-Electron Lasers

Description: The successful lasing at the SLAC National Accelerator Laboratory of the Linear Coherent Light Source (LCLS), the first X-ray free-electron laser (X-ray FEL), in the wavelength range 1.5 to 15 {angstrom}, pulse duration of 60 to few femtoseconds, number of coherent photons per pulse from 10{sup 13} to 10{sup 11}, is a landmark event in the development of coherent electromagnetic radiation sources. Until now electrons traversing an undulator magnet in a synchrotron radiation storage ring provide… more
Date: June 28, 2012
Creator: Pellegrini, C. & /SLAC, /UCLA
Partner: UNT Libraries Government Documents Department
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