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Generation of H sup minus , H sub 2 (v double prime ), and H atoms by H sub 2 sup + and H sub 3 sup + ions incident upon barium surfaces

Description: The generation of vibrationally excited molecules by electron excitation collisions and the subsequent generation of negative ions by dissociative attachment to these molecules has become a standard model for volume source operation. These processes have been supplemented recently by the demonstration of atom-surface recombination to form vibrationally excited molecules, and enhanced negative ion formation by protons incident upon barium electrodes. In this paper we consider the additional proc… more
Date: January 1, 1989
Creator: Hiskes, J.R. & Karo, A.M.
Partner: UNT Libraries Government Documents Department
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Chemiluminescence from the reaction of Ba /sup 3/D with nitric oxide

Description: The reaction of laser excited Ba*(/sup 3/D) states with nitric oxide is presented. BaO product is not detected, although the channel is thermodynamically open, and instead chemiluminescence is observed. Experiments which suggest that radiative recombination, Ba + NO ..-->.. BaNO* ..-->.. BaNO, is the observed reaction channel will also be presented.
Date: January 5, 1977
Creator: Johnson, S. A.; Solarz, R. W.; Dubrin, J. W. & Brotzmann, R.
Partner: UNT Libraries Government Documents Department
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A Modified Pyroelectric Sodium Fluoride Carrier Distillation Medthod For The Spectrographic Analysis Of Impurities In Plutonium

Description: A modification of the pyroelectric sodium fluoride carrier distillation method for analysis of impurities in plutonium metal is described. The metal is dissolved. Plutonium is precipitated and treated with nitric acid. The slurry obtained is dried and ignited. The resultant low density oxide is mixed with sodium fluoride and pressed into a pellet for arcing. Cobalt is used as the internal standard for densitometric using visual comparisons against prepared standards. The procedural modification… more
Date: August 1, 1966
Creator: Schreiber, G. A. & Barrick, C. W.
Partner: UNT Libraries Government Documents Department
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The EPRI Laboratory experiments at ANL. [Vaporization of core-concrete mixtures]

Description: The vaporization of core-concrete mixtures is being measured using a transpiration method. Mixtures of stainless steel, concrete (limestone or basaltic) and urania (doped with La/sub 2/O/sub 3/, SrO, BaO, and ZrO/sub 2/) are vaporized at 2150 - 2400 K from a zirconia crucible into flowing He - 6% H/sub 2/ gas. Up to 600 ppM H/sub 2/O is added to the gas to fix the partial molar free energy of oxygen in the range -420 kJ to -550 kJ. The fraction of the sample that is vaporized is determined by w… more
Date: October 28, 1987
Creator: Roche, M. F.; Settle, J. L.; Leibowitz, L.; Johnson, C. E. & Ritzman, R. L.
Partner: UNT Libraries Government Documents Department
open access

Concentration of stable elements in food products

Description: Food samples were taken from commercial markets and analyzed for stable element content. The concentrations of most stable elements (Ag, Al, As, Au, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Cu, Fe, Hf, I, K, La, Mg, Mn, Mo, Na, Rb, Sb, Sc, Se, Sr, Ta, Th, Ti, V, Zn, Zr) were determined using multiple-element neutron activation analysis, while the concentrations of other elements (Cd, Hg, Ni, Pb) were determined using atomic absorption. The relevance of the concentrations found are noted in relation to o… more
Date: January 1, 1980
Creator: Montford, M. A.; Shank, K. E.; Hendricks, C. & Oakes, T. W.
Partner: UNT Libraries Government Documents Department
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Nuclear methods in coal research

Description: Nuclear methods, particularly neutron activation analysis (NAA) provide useful information about elemental constituents in coal and fly ash, but often other techniques are required to supplement NAA data. Spark source mass spectrometry and atomic absorption have been studied as methods for determination of certain elements in coal that are not easily measured by NAA. In work concerned with the chemical speciation of elements in fly ash, a number of analytical techniques have been used; these in… more
Date: January 1, 1980
Creator: Lyon, W.S.
Partner: UNT Libraries Government Documents Department
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An analytical assessment of the chemical form of fission products during postulated severe accidents in the SRS production reactors

Description: An analysis has been performed to determine the principal chemical forms for the structural and fission product elements during a postulated severe core damage accident in tritium powered core in the Savannah River Site (SRS) reactors. These reactors are powered with UAl{sub x} fuel and are used for the production of weapons materials. Six core elements, cesium, iodine, tellurium, strontium, barium, and lithium, were emphasized in this analysis. Other elements also included were aluminum, hydro… more
Date: January 1, 1991
Creator: Adams, J.P.
Partner: UNT Libraries Government Documents Department
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Barium in Twilight Zone suspended matter as a potential proxy for particulate organic carbon remineralization: Results for the North Pacific

Description: This study focuses on the fate of exported organic carbon in the twilight zone at two contrasting environments in the North Pacific: the oligotrophic ALOHA site (22 degrees 45 minutes N 158 degrees W; Hawaii; studied during June-July 2004) and the mesotrophic Subarctic Pacific K2 site (47 degrees N, 161 degrees W; studied during July-August 2005). Earlier work has shown that non-lithogenic, excess particulate Ba (Ba{sub xs}) in the mesopelagic water column is a potential proxy of organic carbon… more
Date: April 10, 2008
Creator: Dehairs, F.; Jacquet, S.; Savoye, N.; Van Mooy, B. A. S.; Buesseler, K.; Bishop, J. K. B. et al.
Partner: UNT Libraries Government Documents Department
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ORNL fission product release tests VI-6

Description: The ORNL fission product release tests investigate release and transport of the major fission products from high-burnup fuel under LWR accident conditions. The two most recent tests (VI-4 and VI-5) were conducted in hydrogen. In three previous tests in this series (VI-1, VI-2, and VI-3), which had been conducted in steam, the oxidized Zircaloy cladding remained largely intact and acted as a barrier to steam reaction with the UO{sub 2}. Test VI-6 was designed to insure significant oxidation of t… more
Date: January 1, 1991
Creator: Osborne, M. F.; Lorenz, R. A.; Collins, J. L. & Lee, C. S.
Partner: UNT Libraries Government Documents Department
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Radionuclide mobility in the shallow portion of an active high-temperature geothermal system

Description: Accurate knowledge of the behavior of radionuclides in natural rock-water systems is crucial for the prediction of the consequences of failure of a high-level nuclear waste repository. Work in progress at Argonne National Laboratory involves the detailed geochemical analysis of rock, mineral, and water samples from shallow drill holes in a thermal area of Yellowstone National Park. This study is designed to provide data that will increase our understanding of the behavior of a group of radionuc… more
Date: January 1, 1984
Creator: Sturchio, N.C. & Seitz, M.G.
Partner: UNT Libraries Government Documents Department
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Computer-automated neutron activation analysis system

Description: An automated delayed neutron counting and instrumental neutron activation analysis system has been developed at Los Alamos National Laboratory's Omega West Reactor (OWR) to analyze samples for uranium and 31 additional elements with a maximum throughput of 400 samples per day. 5 references.
Date: January 1, 1983
Creator: Minor, M.M. & Garcia, S.R.
Partner: UNT Libraries Government Documents Department
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Atomic and molecular surface and volume processes in the analysis of negative hydrogen discharges

Description: The principal source of negative ion generation in hydrogen discharges is now recognized to be low-energy electron attachment to H/sub 2/(/nu//prime//prime/) molecules excited to the middle portion of the vibrational spectrum. Electron excitation processes are generally taken to be the principal source of H/sub 2/(/nu//prime//prime/) generation, with high-energy excitations through the singlet spectrum being the principal excitation process populating the active portion of the vibrational spect… more
Date: July 3, 1989
Creator: Hiskes, J.R. & Karo, A.M.
Partner: UNT Libraries Government Documents Department
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The soft-sphere model for metals near the critical point

Description: The soft-sphere model is convenient and accurate for predicting fluid phase thermodynamics. The validity of the model for describing the equation-of-state derivatives, Grueneisen's gamma and sound velocity, is shown. 7 refs., 2 figs.
Date: January 1, 1989
Creator: Shaner, J.W.
Partner: UNT Libraries Government Documents Department
open access

The oxidation of Ba dosed Mo(100) surfaces with O/sub 2/ at moderately high temperatures

Description: The oxidation of Mo(100) and Ba-covered Mo(100) by O/sub 2/ have been examined at moderately high temperature (700 to 1400/sup 0/K) using x-ray photoelectron spectroscopy. Results indicate that the Ba or BaO overlayer retards but does not prevent oxidation of the underlying Mo surface. The high temperature surface chemistry of the O/Ba/Mo surface is described. 11 refs., 3 figs.
Date: January 1, 1987
Creator: Rogers, Jr., J. W.; Blair, D. S. & Paffett, M. T.
Partner: UNT Libraries Government Documents Department
open access

Potential uses of silica-bonded macrocyclic ligands for separation of metal ions from nuclear waste

Description: This paper explores the potential of a relatively new separation material that is obtained by covalently binding macrocyclic ligands to silica gel. Fortunately, neutral macrocyclic ligands can be bound to silica gel such that metal binding constants do not differ significantly from the binding constants of the free ligands so that selectivities of free macrocyclic ligands can be used in designing silica-bound materials with appropriate selectivities. Accordingly, macrocyclic ligands known to ha… more
Date: November 1, 1991
Creator: Bruening, R.L. (IBC Advanced Technologies, Inc., Provo, UT (United States)); Camaioni, D.M.; Colton, N.G. & Morrey, J.R. (Pacific Northwest Lab., Richland, WA (United States))
Partner: UNT Libraries Government Documents Department
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Mechanistic model for Sr and Ba release from severely damaged fuel

Description: Among radionuclides associated with fission product release during severe accidents, the primary ones with health consequences are the volatile species of I, Te, and Cs, and the next most important are Sr, Ba, and Ru. Considerable progress has been made in the mechanistic understanding of I, Cs, Te, and noble gas release; however, no capability presently exists for estimating the release of Sr, Ba, and Ru. This paper presents a description of the primary physical/chemical models recently incorp… more
Date: November 1, 1985
Creator: Rest, J. & Cronenberg, A.W.
Partner: UNT Libraries Government Documents Department
open access

Development of a dc low pressure D sup minus surface-conversion source using a 10-cm-diameter solid barium converter

Description: A D{sup {minus}} surface-conversion source using a solid barium converter is designed for steady-state operation to produce 200 mA of D{sup {minus}}. A similar ion source of twice the size as the one discussed here will meet the requirements set by the present US-ITER neutral beam injector design. Among the possible types of ion sources being considered for the US-ITER neutral beam design, the barium converter surface-conversion source is the only kind that does not use cesium in the discharge.… more
Date: September 1, 1991
Creator: Kwan, J. W.; Anderson, O. A.; Chan, C. F.; Cooper, W. S.; deVries, G. J.; Kunkel, W. B. et al.
Partner: UNT Libraries Government Documents Department
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Kinetics of fission product release prior to fuel slumping

Description: This paper describes the primary physical/chemical models recently incorporated into a mechanistic code (FASTGRASS) for the estimation of fission product release from fuel, and compares predicted results with test data. The theory of noble gas behavior is discussed in relation to its effect on the release behavior of I, Cs, Te, Ba, and Sr. The behavior of these fission products in the presence of fuel liquefaction/dissolution and oxidation grain-growth phenomena is presented, as is the chemistr… more
Date: October 1, 1987
Creator: Rest, J.
Partner: UNT Libraries Government Documents Department
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Creating unstable velocity-space distributions with barium injections

Description: Large Debye lengths relative to detector dimensions and the absence of confining walls makes space an attractive laboratory for studying fundamental theories of plasma instabilities. However, natural space plasmas are rarely found displaced from equilibrium enough to permit isolation and diagnosis of the controlling parameters and driving conditions. Furthermore, any plasma or field response to the departure from equilibrium can be masked by noise in the natural system. Active experiments provi… more
Date: January 1, 1983
Creator: Pongratz, M.B.
Partner: UNT Libraries Government Documents Department
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Immobilization of high level nuclear reactor wastes in SYNROC: a current appraisal. [Synthetic perovskite and hollandite; natural zirconolite and perovskite]

Description: Results are presented for leach testing at 95/sup 0/C and 200/sup 0/C of SYNROC containing 9% and 20% simulated high level radioactive waste, synthetic hollandite and pervoskite samples, and natural zirconolite and pervoskite samples. Single phase synthetic minerals show much higher leach rates than natural mineral samples and polyphase SYNROC samples. Natural zirconolite samples with low radiation damage have leach rates at 200/sup 0/C based on U which are identical to those measured on SYNROC… more
Date: October 13, 1981
Creator: Oversby, V.M. & Ringwood, A.E.
Partner: UNT Libraries Government Documents Department
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Wet oxidation of oil-bearing sulfide wastes

Description: Oil-bearing metal sulfide sludges produced in treatment of an industrial wastewater, which includes plating wastes, have yielded to treatment by electrooxidation and hydrogen peroxide processes. The oxidation can be controlled to be mild enough to avoid decomposition of the organic phase while oxidizing the sulfides to sulfates. The pH is controlled to near neutral conditions where iron, aluminum and chromium(III) precipitate as hydrous oxides. Other metals, such as lead and barium, may be pres… more
Date: January 1, 1991
Creator: Miller, R. L. & Hotz, N. J.
Partner: UNT Libraries Government Documents Department
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Resonance and Threshold Effects in Photoemission Up to 3500 eV

Description: Beam lines at the Stanford Synchrotron Radiation Laboratory (SSRL) now provide photon beams throughout the entire energy range 5 to 5000 eV, with a pulse structure very well-suited to time-of-flight (TOF) photoelectron spectroscopy. We have used this facility, together with a TOF spectrometer, to measure photoemission cross sections sigma(epsilon) and asymmetry parameters ..beta..(epsilon) for several interesting systems. A summary of early results is given. Metal vapors (Ba, Cd, Mn, Hg) were s… more
Date: August 1, 1982
Creator: Shirley, D. A.; Kobrin, P. H.; Lindle, D. W.; Truesdale, C. M.; Southworth, S. H.; Becker, U. et al.
Partner: UNT Libraries Government Documents Department
open access

Potential uses of silica-bonded macrocyclic ligands for separation of metal ions from nuclear waste

Description: This paper explores the potential of a relatively new separation material that is obtained by covalently binding macrocyclic ligands to silica gel. Fortunately, neutral macrocyclic ligands can be bound to silica gel such that metal binding constants do not differ significantly from the binding constants of the free ligands so that selectivities of free macrocyclic ligands can be used in designing silica-bound materials with appropriate selectivities. Accordingly, macrocyclic ligands known to ha… more
Date: November 1, 1991
Creator: Bruening, R. L.; Camaioni, D. M.; Colton, N. G. & Morrey, J. R.
Partner: UNT Libraries Government Documents Department
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