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A SURVEY REPORT ON LITHIUM HYDRIDE

Description: ABS>The physical and chemical properties of lithium hydride are described, based on reasonably full coverage of the available unclassified literature as of July 1, 1960. Where possible, the data are presented critically. Lithium deuteride and lithium hydride gases are included. Practical matters such as thermal stability, corrosive character, utilization, handling, fabrication, and analysis are discussed. This report replaces report NYO-3957 and its supplement NYO-8022. 230 references. (auth)
Date: October 27, 1960
Creator: Messer, C.E.
Partner: UNT Libraries Government Documents Department

THE SPECTRA OF SOME ALIPHATIC ALDEHYDES AND THEIR MONODEUTERO DERIVATIVES (Part I of Thesis)

Description: BS>An investigation of the infrared and near-ultraviolet spectra of three aliphatic aldchydes and their monodeutero derivatives is described. The infrared spectra of the acetaldehydes (CH/sub 3/CHO and CH/sub 3/CDO) were in agreement with work reported recently. A few new bands are reported and discussed. The infrared spectra of C/sub 2/H/sub 5/CHO, C/sub 2/H/sub 5/CDO, C/ sub 3/H/sub 7/CHO, and C/sub 3/H/sub 7/CDO at 450 to 4000 cm/sup -1/ were observed, and an assignment of the observed bands was made. The weak absorption of the aliphatic aldehydes which extends from lambda 3500 A to lambda 2300 A was investigated. The strength of the absorption (f-value) is decreased by deuterium substitution at the aldehyde CHO group. The decrease in the f-value can be accounted for by the theory of vibrationally induced electronic transitions. The effect of isotopic substitution on the intensity of symmetry- allowed as well as synnmetryforbidden (vibrationally allowed) electronic transitions in polyatomic molecules is discussed. (auth)
Date: October 1, 1958
Creator: Worden, E.F. Jr.
Partner: UNT Libraries Government Documents Department

Propane Vibrational Analysis

Description: Using the group vibratibn method of McMurry, the normal frequencies and coordinates of propane and three of its symmetrical deuterium substituted compounds were obtained. The force constants used were taken from a variety of previous works on hydrocarbons. The results give reasonable agreements with the experimental frequency and mode assignments of others. (auth)
Date: June 12, 1962
Creator: Marshall, G. D.
Partner: UNT Libraries Government Documents Department

Predicting laser-induced bulk damage and conditioning for deuterated potassium di-hydrogen phosphate crystals using ADM (absorption distribution model)

Description: We present an empirical model that describes the experimentally observed laser-induced bulk damage and conditioning behavior in deuterated Potassium dihydrogen Phosphate (DKDP) crystals in a self-consistent way. The model expands on an existing nanoabsorber precursor model and the multi-step absorption mechanism to include two populations of absorbing defects, one with linear absorption and another with nonlinear absorption. We show that this model connects previously uncorrelated small-beam damage initiation probability data to large-beam damage density measurements over a range of ns pulse widths relevant to ICF lasers such as the National Ignition Facility (NIF). In addition, this work predicts the damage behavior of laser-conditioned DKDP and explains the upper limit to the laser conditioning effect. The ADM model has been successfully used during the commissioning and early operation of the NIF.
Date: February 26, 2010
Creator: Liao, Z M; Spaeth, M L; Manes, K; Adams, J J & Carr, C W
Partner: UNT Libraries Government Documents Department

The Reaction Between Sulfuric Acid and Aliphatic Hydrocarbons. Amsco 125- 82

Description: Concentrated sulfuric acid is regularly used to remove unsaturated hydrocarbon impurities from saturated aliphatic hydrocarbons. The reaction between concentrated sulfuric acid and saturated aliphatic hydrocarbons is not so well known. A survey of the chemical literature was found to include studies that show several relatively slow reactions. Isotopic exchange with D/sub 2/SO/ sub 4/, racemization of optically active alkanes, isomerization, cleavage to alkanes of lower molecular weight, combination to compounds of higher molecular weight and the formation of SO/sub 2/ were recognized. Amsco 125-82, the diluent used in solvent extraction, reacts with sulfuric acid forming sulfur dioxide and low boiling hydrocarbon fragments. The over-all reaction probably results in the formation of more stable hydrocarbons by rearrangement. The sulfuric acid treatment can thus produce a more desirable diluent. (auth)
Date: June 1, 1960
Creator: Baldwin, W. H.
Partner: UNT Libraries Government Documents Department

Secondary Isotope Effects in Molecular Structure

Description: A study was made to determine whether secondary iso tope effects also occur in molecular structure. Electron diffraction studies were carried out on ethane and deuteroethane. In C/sub 2/H/sub 6/ the mean C-C and C-H bond lengths found agreed very closely with values determined for other paraffin hydrocarbons, and the C--H bond showed a normal primary isotope effect (~ 0.005 A) similar to that found in methane when H is replaced by O. The output of the leastsquares analysis suggested that the mean C-- C bond length in C/sub 2/D/sub 6/ is shorter than in C/sub 2/H/sub 6/ and by about 0.004 A. Th e decrease seemed to be real for the apparent uncertainty was not much greater than 0.001 A. (M.C.G.)
Date: June 15, 1962
Creator: Bartell, L. S.
Partner: UNT Libraries Government Documents Department

STUDIES RELATING TO THE STRUCTURE OF ALUMINUM HYDRIDE (thesis)

Description: The object of the work was to determine the molecular structure of AlH/ sub 3/, using the techniques of nuclear spin resonance.'' Attempts to prepare ether-free AlH/sub 3/ that were unsuccessful are described. Also it was not possible to observe the deuterium signal in AlH/sub 3/. It was possible, by the use of the proton signal of the ether in AlH/sub 3/, to obtain the nuclear spin resonance absorption curve for AlH/sub 3/ by subtracting out the contributions of the ether protons to the resonance signai. A model is proposed to explain the features of the nuclear spin resonance absorption curve. The existence of LiAl/ sub 2/H/sub 7/, which has been postulated elsewhere, is assumed in order to explain the datu obtained from high-resolution nuclear spin resonance experimeats. (auth)
Date: December 16, 1957
Creator: Nickerson, R.F.
Partner: UNT Libraries Government Documents Department

Filament preheating for phi targets

Description: The vaporization and preheating of a CD/sub 2/ filament inside a target is examined to investigate operation of such a target. The experimental arrangement duplicated the previous shots, with prepulse levels of 40 to 120 kV and several kA, and use of identical phi targets with CD/sub 2/ filaments. The behavior of the filament was observed by optical methods and was seen to consist of luminous and plasma phases in turn. This behavior is consistent with earlier hypotheses concerning phi target operation.
Date: February 1, 1979
Creator: Olsen, J.N.
Partner: UNT Libraries Government Documents Department

Visualization of monoamine oxidase in human brain

Description: Monoamine oxidase is a flavin enzyme which exists in two subtypes, MAO A and MAO B. In human brain MAO B predominates and is largely compartmentalized in cell bodies of serotonergic neurons and glia. Regional distribution of MAO B was determined by positron computed tomography with volunteers after the administration of deuterium substituted [11C]L-deprenyl. The basal ganglia and thalamus exhibited the greatest concentrations of MAO B with intermediate levels in the frontal cortex and cingulate gyrus while lowest levels were observed in the parietal and temporal cortices and cerebellum. We observed that brain MAO B increases with are in health normal subjects, however the increases were generally smaller than those revealed with post-mortem studies.
Date: December 31, 1996
Creator: Fowler, J.S.; Volkow, N.D.; Wang, G.J.; Pappas, N.; Shea, C.; MacGregor, R.R. et al.
Partner: UNT Libraries Government Documents Department

Transient radiation effects in D.O.I. optical materials: KD{sup *}P

Description: Department of Energy and Defense Programs systems are becoming increasingly reliant on the use of optical technologies that must perform under a range of ionizing radiation environments. In particular, the radiation response of materials under consideration for applications in direct optical initiation (D.O.I.) schemes must be well characterized. In this report, transient radiation effects observed in a KD*P crystal are characterized. Under gamma exposure with 2 MeV photons in a 20--30 nsec pulse, the authors observe induced absorption at 1.06 {micro}m that causes a peak decrease in overall sample transmittance of only 10%. This induced loss is seen to recover fully within the first 30 {micro}sec.
Date: July 1, 1998
Creator: Simmons-Potter, K.
Partner: UNT Libraries Government Documents Department

Phase coexistence in proton glass

Description: Proton glasses are crystals of composition M{sub 1{minus}x}(NW{sub 4}){sub x}W{sub 2}AO{sub 4}, where M = K,Rb, W = H,D, A = P,As. For x = 0 there is a ferroelectric (FE) transition, while for x = 1 there is an antiferroelectric (AFE) transition. In both cases, the transition is from a paraelectric (PE) state of tetragonal structure with dynamically disordered hydrogen bonds to an ordered state of orthorhombic structure. For an intermediate x range there is no transition, but the hydrogen rearrangements slow down, and eventually display nonergodic behavior characteristic of glasses. The authors and other have shown from spontaneous polarization, dielectric permittivity, nuclear magnetic resonance, and neutron diffraction experiments that for smaller x there is coexistence of ferroelectric and paraelectric phases, and for larger x there is coexistence of antiferroelectric and paraelectric phases. The authors present a method for analytically describing this coexistence, and the degree to which this coexistence is spatial or temporal.
Date: November 1, 1996
Creator: Schmidt, V.H.; Trybula, Z.; Pinto, N.J. & Shapiro, S.M.
Partner: UNT Libraries Government Documents Department

Producing KDP and DKDP crystals for the NIF laser

Description: The cost and physics requirements of the NIF have established two important roles for potassium dihydrogen phosphate (KDP) crystals. 1. To extract more laser energy per unit of flashlamp light and laser glass, the NIF has adopted a multipass architecture as shown in Figure 1. Light is injected in the transport spatial filter, first traverses the power amplifiers, and then is directed to main amplifiers, where it makes four passes before being redirected through the power amplifiers towards the target. To enable the multipass of the main amplifiers, a KDP-containing Pockels cell rotates the polarization of the beam to make it either transmit through or reflect off a polarizer held at Brewster's angle within the main laser cavity. If transmitted, the light reflects off a mirror and makes another pass through the cavity. If reflected, it proceeds through the power amplifier to the target. the original seed crystal as the pyramid faces grow. Unfortunately, this pyramidal growth is very slow, and it takes about two years to grow a crystal to NIF size. To provide more programmatic flexibility and reduce costs in the long run, we have developed an alternative technology commonly called rapid growth. Through a combination of higher temperatures and higher supersaturation of the growth solution, a NIF-size boule can be grown in 1 to 2 months from a small ''point'' seed. However, growing boules of adequate size is not sufficient. Care must be taken to prevent inclusions of growth solution and incorporation of atomically substituted 2. Implosions for ICF work far better at shorter wavelengths due to less generation of hot electrons, which preheat the fuel and make it harder to compress. Compromising between optic lifetime and implosion efficiency, both Nova and the NIF operate at a tripled frequency of the 1053-nm fundamental frequency of a neodymium ...
Date: September 2, 1999
Creator: Atherton, L J; Burnham, A K; Combs, R C; Couture, S A; De Yoreo, J J; Hawley-Fedder, R A et al.
Partner: UNT Libraries Government Documents Department

Dissociation of Molecular Ions by Electric Fields [Part 2]

Description: The reactions pi /sup -/ + p yields p + p + n and pi /sup -/ + p yields p + d were investigated. The calculations are based on thirdorder perturbation theory with pseudoscalar coupling between nucleons and pions and with a phenomenological treatment of the nucleon-nucleon interaction in the final state. The final-state interactions of the antinucleon are neglected. Cross sections are given in graphical form for the reactions and for trsnsitions between eigenstates of isotopic spin. The final-state nucleon-nucleon interaction is shown to have a lnrge effect on the cross sections. The cross section for the reaction pi /sup -/ + p yields p + d is found to be relatively large. At an energy of 10 Mev abcve threshold in the center-of-momentum system the ratio of this cross section to that for pi /sup -/ + p yields p + p + n is about 5: 1. At an energy of 40 Mev above threshold this ratio hns decreased to 1: I. The total cross section for the reaction leading to the unbound final state is calculated by assuming a modified Fermi statistical model. At an energy 100 Mev above threshold, this cross section is approximately 0.1 mb. A theoretical expression for the transition amplitude is developed. (auth)
Date: May 1, 1960
Creator: Hiskes, J. R.
Partner: UNT Libraries Government Documents Department