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Liquid Metal Loops Irradiated on the ORNL Graphite Reactor and the LITR

Description: From abstract: Liquid alkali metals were circulated in a series of structural alloy loops under reactor radiation at high temperature. The first of these loops was a lithium-stainless steel (type 316) system, and the remainder were sodium-Inconel. No effect of radiation other than radioactivation was found. Mass transfer and metallurgical processes attributable to the operating temperatures were observed."
Date: June 1, 1959
Creator: Parkinson, W. W. & Sisman, O.
Partner: UNT Libraries Government Documents Department

Ligand-Thickness Effect Leads to Enhanced Preference for Large Anions in Alkali Metal Extraction by Crown Ethers

Description: Jean-Marie Lehn (Nobel laureate, 1987) suggested ligand thickness to be an important consideration in the design of host molecules for cation recognition. We have recently expanded the role of this simple ligand property by demonstrating a case in which ligand thickness contributes significantly to anion discrimination. It was found that in the extraction of sodium nitrate and perchlorate by a simple crown ether, bis(t-octylbenzo)-14-crown-4 (BOB 14C4), the normal preference for perchlorate is almost completely lost when the complex cation has the open-face sandwich vs. the sandwich structure.
Date: July 11, 1999
Creator: Haverlock, T.J.; Moyer, B.A. & Sachleben, R.A.
Partner: UNT Libraries Government Documents Department

Spectroscopic Investigation of Some Allyl Alkali Metal Compounds

Description: To gain better understanding of the nature of the carbonmetal bonding in 3-neopentylallyl alkali metal (5,5-dimethyl- 2-hexenyl alkali metal) systems, an investigation is extended to 3-neopentylallylpotassium. In addition, pertinent data on the 3-neopentylallyl systems are re-examined in an attempt to understand the trends in the bonding habits, as affected by the solvent, the cation and the temperature.
Date: May 1976
Creator: Moore, Michael L.
Partner: UNT Libraries

On the neutralization of singly and multicharged projectiles during grazing interactions with LiF(100)

Description: Measurements are reported of scattered neutral fractions for Na, K, Cs, and Ne singly and multicharged ions, and of scattered negative ion fractions for incident O, F, and B projectiles grazingly incident on LiF(100) as function of projectile velocity. In the case of the Na and Ne incident ions, significant dependence of the scattered neutral fractions on incident charge state is found, which is most pronounced at the lowest investigated velocities. Possible reasons for the observed initial charge state dependence are considered. In addition, results are reported for the target azimuthal dependence of the final neutral fraction observed for grazingly incident 35 keV Cs{sup +7} ions.
Date: October 1996
Creator: Meyer, F. W.; Yan, Q.; van Emmichoven, P. Z.; Spierings, G. & Hughes, I. G.
Partner: UNT Libraries Government Documents Department

An orthotropic source of thermal atoms

Description: A source of thermal atoms that emits 100% of its atoms into a narrow beam with small angular divergence is described. It uses both surface ionization and surface neutralization in conjunction with electric fields to selectively emit a highly directional (orthotropic) beam of neutral atoms. The ion recycling process can be modulated electronically and lends itself to scanning. This orthotropic source is ideal for the efficient use of rare atomic species, well suited for atomic clocks, essential in the efficient delivery of radioactive atoms to optical traps, and has potential to produce ultra high intensity beams of stable atoms.
Date: July 1, 1995
Creator: Dinneen, T.; Ghiorso, A. & Gould, H.
Partner: UNT Libraries Government Documents Department

An Annotated Bibliography of Analytical Methods for Alkali Metals

Description: A total of 107 abstracts is presented on analytical methods for alkali metals, as a part of a program for the evaluation of the performance of the primary cold trap from the Enrico Fermi Reactor. The abstracts are arranged into sections dealing with general aspects; sampling and dissolution techniques; and determination of uncombined alkali metal, oxygen, carbon, hydrogen, nitrogen, and other impurities. (D.L.C.)
Date: March 1, 1964
Creator: Garcia, E. E. & LaMont, B. D.
Partner: UNT Libraries Government Documents Department

Chemical Engineering Division Basic Energy Sciences Research: July 1976-September 1977

Description: Studies in basic energy science covered many different activities, nearly all of which were designed to gain information required for a better understanding of systems important to national needs in energy and environment. Studies of associating gases included measurements of thermal conductivities and basic molecular orbital calculations. Raman spectroscopy and spectrophotometry were used to determine thermodynamic and spectroscopic data on salt vapor complexes. Polarized Raman spectra of As2S3 thin films and vapors were recorded. Halogenation of lanthanide oxides with aluminum chloride allowed the separation of the resultant chloride complexes by vapor transport. Electrochemical titrations were used to obtain the solubility product of iron sulfide in molten LiCl-KCl eutectic. Solubility products of eleven sulfides in the same eutectic mixture were calculated. Galvanostatic techniques were used to study metal deposition/dissolution reactions in molten salts. Activity coefficients of lithium in lithium-lead alloys were determined electrochemically; phase diagrams of ternary alloys of Li-Al-Mg and Li-Ca-Mg were computed. Thermodynamic studies are being made of the sorption of hydrogen by Li-Al and Li-Pb alloys. The study of the solubility of oxygen in liquid lithium was completed. An electric resistance method for measuring distribution properties of nonmetallic elements in binary metallic systems containing lithium is being developed. Calorimetric methods were used to measure standard enthalpies of formation of some coal components, lanthanum and rare earth trifluorides, and gamma-UO3, UF6, Cs3CrO4, Cs4CrO4, As4S4, and As2S3. High-temperature enthalpy increments were measured for LaF3 and beta-As4S4. The acidities of airborne ammonium sulfate-bearing particles from various areas of the U.S. were measured using Fourier-transform infrared spectroscopy.
Date: 1978?
Creator: Cafasso, F. A.; Blander, M.; Maroni, V. A.; Johnson, C. E.; Kumar, R. & Siegel, S.
Partner: UNT Libraries Government Documents Department


Description: Calculations are presented of the amount of mass transfer to be expected in liquid alkali metal-Ni alloy systems for two assumed diffusion mechanisms. In one, the boundary layer is assumed saturated and the transfer rate is limited by the rate of diffusion of solute into the liquid. In the other, the mass transfer rate is assumed to be limited by the diffusion rate of a component of the solid alloy to the solid surface. It is concluded tbat a more general hypothesis is needed. (T.R.H.)
Date: July 22, 1957
Creator: Keyes, J.J. Jr.
Partner: UNT Libraries Government Documents Department


Description: ABS>The preparation of germanium hydrides, by the dropwise addition of al alkaline solution of hydroborate and germanate to aqueous acid, was studied systematically. As much as 70% of the germanium in solution could be converted to germane, Digermane, trigermane, and a polymeric germane were also obtained, and the infrared absorption spectra of gaseous trigermane and of polymeric germane were recorded. (auth)
Date: May 18, 1961
Creator: Drake, J.E.
Partner: UNT Libraries Government Documents Department


Description: The vapors of potassium, rubidium, and cesium have been photoionized with light absorbed in the discrete region of the atomic spectrum. The energy threshold for the ionization process has been determined and the ions produced identified by mobility measurements. The data give lower limits for the dissociation energies of K{sup +2}, Rb{sup +2} and Cs{sup +2}. Each of these molecular ions has a bond energy approximately 50% greater than that of the corresponding neutral molecule. In addition, lower limits for the electron affinities of the alkali atoms and approximate values for the mobilities of Rb{sup +} and Rb{sup +2} in rubidium vapor are given.
Date: February 1, 1965
Creator: Lee, Yuan-tseh & Mahan, Bruce H.
Partner: UNT Libraries Government Documents Department

Heat pipe transient response approximation.

Description: A simple and concise routine that approximates the response of an alkali metal heat pipe to changes in evaporator heat transfer rate is described. This analytically based routine is compared with data from a cylindrical heat pipe with a crescent-annular wick that undergoes gradual (quasi-steady) transitions through the viscous and condenser boundary heat transfer limits. The sonic heat transfer limit can also be incorporated into this routine for heat pipes with more closely coupled condensers. The advantages and obvious limitations of this approach are discussed. For reference, a source code listing for the approximation appears at the end of this paper.
Date: January 1, 2001
Creator: Reid, R. S. (Robert Stowers)
Partner: UNT Libraries Government Documents Department

Electron capture from occupied surface states within the band gap of LiF(100)

Description: Measurements of scattered neutral fractions for Na, K, and Cs multicharged ions grazingly incident on Li(100) as function of projectile velocity suggest that near resonant processes are active in the final neutral formation, involving occupied surface states within the band gap of the alkali halide target. Observed scattered negative fractions for incident 0, F. and B projectiles are consistent with such a scenario as well. A model treatment of the projectile charge fraction velocity dependence is utilized to deduce from the experimental data a work function and Fermi energy of 3.8 eV and 0.8 eV, respectively, for this surface band. Measurement of the parallel velocity dependence of the image charge acceleration of Ne{sup 6+} grazingly incident on LiF(100) in the range 0.1 - 0.52 a.u. are shown to provide further support for the presence of a band of surface states having the above parameters.
Date: September 1, 1996
Creator: Yan, Q. & Meyer, F.W.
Partner: UNT Libraries Government Documents Department

High Temperature Akali Corrosion of Dense SiC and Si(3)N(4) Coated with CMZP and Mg-Doped Al(2)TiO(5) in Coal Gas

Description: Si{sub 3}N{sub 4} ceramics possess properties that are attractive for high temperature heat exchanger applications. These properties include high strength, good thermal conductivity and excellent resistance to thermal shock and oxidation. However when subjected to alkaline containing environments, Si{sub 3}N{sub 4} is prone to corrode and eventually loses its properties. Because it was found that oxide ceramics corrode substantially less, they can be used as a coating to protect Si{sub 3}N{sub 4}. Therefore the first objective of this work is to develop thin film of CMZP and Mg-doped Al{sub 2}TiO{sub 5} since both of them are good candidate coating materials of primary interest for the protection of Si{sub 3}N{sub 4} against alkaline corrosion.
Date: April 15, 1997
Creator: Thierry, N. & Brown, J.J.
Partner: UNT Libraries Government Documents Department