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RIMS diagnostics for laser desorption/laser ablation

Description: Laser desorption mass spectrometry is a useful method for interrogating materials and events at or near surfaces. Laser desorption/ablation combined with Resonance Ionization Mass Spectrometry (RIMS) provides a powerful tool to obtain information on chemical composition and speciation and, in some cases, internal and translational energy distributions. The application of this technique to the interrogation of materials and interfaces is discussed for several systems, including the analysis of c… more
Date: January 1, 1986
Creator: Apel, E. C.; Nogar, N. S.; Miller, C. M. & Estler, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Resonance ionization mass spectrometry at Los Alamos National Laboratory

Description: Two approaches to RIMS will be discussed here. The first is the use of continuous-wave (cw) dye lasers as the ionization source. Continuous excitation effectively matches the ionization to the evaporation of sample from a resistively heated filament, providing for efficient use of the sample. In addition, cw ionization permits pulse counting detection, necessary for the measurement of large isotope ratios on small samples. In the cases of lutetium and technetium discussed below, average ionizat… more
Date: January 1, 1986
Creator: Miller, C. M.; Nogar, N. S.; Apel, E. C. & Downey, S. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Physicochemical basis of the Na-K-Ca geothermometer

Description: Regular changes in solution composition were observed experimentally during granite reaction with dilute NaCl (+CaCl/sub 2/) solutions; these changes closely follow the empirical Na-K-Ca geothermometer relationship. Initial minerals forming the granite (quartz, plagioclase, K-feldspar, and biotite) were etched by the reactions. Alteration phases formed include calcium-zeolite at <300/sup 0/C, feldspar overgrowths at >300/sup 0/C, and minor amounts of clay and calcsilicate at all temperatures. A… more
Date: August 1, 1986
Creator: Janecky, D. R.; Charles, R. W.; Bayhurst, Gregory K. & Benjamin, T. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Anti p-nucleus interaction

Description: Status and future prospects of antiproton-nucleus scattering experiments are presented. These scattering experiments were conducted at antiproton beam momentums of 300 and 600 MeV/c on target nuclei of /sup 6/Li, /sup 12/C, /sup 16/O, /sup 18/O, /sup 40/Ca, /sup 48/Ca, and /sup 208/Pb. Antiproton-proton reactions investigated antiproton-nucleus bound or resonant states in antiproton reactions with d, /sup 6/Li, /sup 12/C, /sup 63/Cu, and /sup 209/Bi. Inelastic scattering experiments investigate… more
Date: May 1, 1986
Creator: Peng, J.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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EMC Effect

Description: A review is presented of data and theoretical interpretations of the nuclear dependence of quark and antiquark distributions as observed in the deep inelastic scattering of neutrinos and charged leptons from nuclei. After a summary of the experimental situation and a survey of the broad spectrum of proposed explanations, I concentrate on the Q/sup 2/-rescaling approach and on interpretations in terms of conventional nuclear physics. The review concludes with a list of desirable future experimen… more
Date: June 1, 1986
Creator: Berger, E. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of incomplete fusion for light heavy-ion systems using velocity distributions

Description: Experimental results on incomplete fusion for light systems are discussed by studying the velocity distribution of fusion-like residues in the energy range of 6 to 20 MeV/nucleon. Original experimental work and results from other groups including the Hahn-Meitner Institute and the Argonne National Laboratory are also cited. Reactions between /sup 14/N, /sup 16/O, /sup 19/F, and /sup 20,22/Ne projectiles and /sup 24,26/Mg, /sup 27/Al, /sup 28/Si, /sup 40/Ca and /sup 58,60/Ni targets have been st… more
Date: March 1, 1986
Creator: Chan, Y.; Albiston, C.; Bantel, M.; Budzanowski, A.; DiGregorio, D.; Stokstad, R.G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fusion-fission in the /sup 16/O + /sup 40,44/Ca and /sup 32/S + /sup 24/Mg reactions

Description: In measurements of fully-damped yields for the /sup 16/O + /sup 40,44Ca and /sup 32/S + /sup 24/Mg reactions, evidence for a fusion-fission reaction mechanism were found. The experiments were performed at the Argonne tandem-linac booster facility. Reaction products with masses 22 < A < 36 for the /sup 16/O + /sup 40,44Ca reactions and 10 < A < 28 for the /sup 32/S + /sup 24/Mg reaction were detected and identified using the time-of-flight technique. The /sup 16/O + /sup 40,44Ca reactions were m… more
Date: March 1, 1986
Creator: Sanders, S. J.; Back, B. B.; Betts, R. R.; Dichter, B. K.; Kaufman, S.; Kovar, D. G. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Elemental concentrations in bones from an ancient Egyptian mummy and from a recent man

Description: Differences in elemental concentrations in bones taken from an ancient Egyptian mummy and a contemporary man were investigated by using proton induced x-ray emission (PIXE) in combination with Rutherford backscattering (RBS). Remarkable differences were noticed in the Fe/Ca and Pb/Ca relative concentrations, which were consistently higher in the contemporary man. 5 refs., 2 figs., 2 tabs.
Date: June 1, 1986
Creator: Cholewa, M.; Kwiatek, W. M.; Jones, K. W.; Schidlovsky, G.; Paschoa, A. S.; Miller, S. C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Preparation of fused chloride salts for use in pyrochemical plutonium recovery operations at Los Alamos

Description: The Plutonium Metal Technology Group at Los Alamos routinely uses pyrochemical processes to produce and purify plutonium from impure sources. The basic processes (metal production, metal purification, and residue treatment) involve controlling oxidation and reduction reactions between plutonium and its compounds in molten salts. Current production methods are described, as well as traditional approaches and recent developments in the preparation of solvent salts for electrorefining, molten salt… more
Date: July 1, 1986
Creator: Fife, K. W.; Bowersox, D. F.; Christensen, D. C. & Williams, J. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron-induced gamma-ray spectroscopy: simulations for chemical mapping of planetary surfaces

Description: Cosmic rays interact with the surface of a planetary body and produce a cascade of secondary particles, such as neutrons. Neutron-induced scattering and capture reactions play an important role in the production of discrete gamma-ray lines that can be measured by a gamma-ray spectrometer on board of an orbiting spacecraft. These data can be used to determine the concentration of many elements in the surface of a planetary body, which provides clues to its bulk composition and in turn to its ori… more
Date: January 1, 1986
Creator: Brueckner, J.; Waenke, H. & Reedy, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Roles of Calcium Ions and Cyclic AMP in Olfactory Transduction

Description: The roles of Ca2 + and cAMP in olfactory transduction were explored using agents which affect calcium channels and second messenger systems. These agents were applied at certain calculated final concentrations onto olfactory epithelia of urethane-anesthetized frogs (Sana PiPlens) by two-sec aerosol spray. During extracellular recording, saturated vapors of isoamyl acetate were delivered every 100 sec in 0.3 sec pulses to produce an electroolfactogram (EOG). Inorganic cations that block inward … more
Date: December 1986
Creator: Winegar, Bruce D. (Bruce David)
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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Conversion of forest residues to a methane-rich gas. Phase completion report

Description: This report describes the progress made to investigate the use of various catalysts and methods of incorporation for the gasification of forest residue materials. Catalyst effectiveness was determined by measuring the gasification rate directly in a differential reactor that utilized approximately one gram samples and by gasifying approximately 10 to 20 gram samples in a batch-solids fluid bed (BSFB) to determine the effect of catalysts on product gas composition. 2 refs., 24 figs., 12 tabs.
Date: March 1, 1986
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemistry of brines in salt from the Waste Isolation Pilot Plant (WIPP), southeastern New Mexico: a preliminary investigation

Description: We present here analyses of macro- and microscopic (intracrystalline) brines observed within the WIPP facility and in the surrounding halite, with interpretations regarding the origin and history of these fluids and their potential effect(s) on long-term waste storage. During excavation, several large fluid inclusions were recovered from an area of highly recrystallized halite in a thick salt bed at the repository horizon (2150 ft below ground level). In addition, 52 samples of brine ''weeps'' … more
Date: March 1, 1986
Creator: Stein, C.L. & Krumhansl, J.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transfer reactions with heavy elements

Description: Transfer reactions for several transuranium elements are studied. (/sup 248/Cm, /sup 249/Bk, /sup 249/CF, /sup 254/Es), /sup 16,18/O, /sup 20,22/Ne, and /sup 40,48/Ca projectiles are used. The production of neutron-rich heavy actinides is enhanced by the use of neutron-rich projectiles /sup 18/O and /sup 22/Ne. The maxima of the isotopic distributions occur at only 2 to 3 mass numbers larger for /sup 48/Ca than for /sup 40/Ca reactions with /sup 248/Cm. The cross sections decrease rapidly with … more
Date: April 1, 1986
Creator: Hoffman, D.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Two-electron capture and loss in fast highly charged ion-atom collisions

Description: Two-electron capture and loss processes have been investigated for highly charged ions colliding with gas targets in the energy range 0.5 to 9.0 MeV/u. Ionic species used for projectiles were S(13+), Ar(15+), Ca(12-19+), and V(18-22+); target gases used were H2, He, and Ne. Double-electron capture decreases very rapidly with increasing beam energy, and the cross sections are typically 1 to 2 orders of magnitude smaller than the single-electron capture cross sections over the energy range studie… more
Date: January 1, 1986
Creator: Tanis, J. A.; Bernstein, E. M.; Clark, M. W.; Graham, W. G.; McFarland, R. H.; Morgan, T. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Entrance Channel Limitations in the High Energy Fusion of Light-Heavy Systems Leading to /sup 40/Ca and /sup 42/Ca

Description: The question of compound nucleus or entrance channel-type limitation to the fusion cross section has been approached effectively in experiments where the same compound nucleus is populated by different projectile-target combinations. Fusion data are available for several systems leading to the compound nuclei /sup 40/Ca and /sup 42/Ca. In this study we report on measurements of fusion cross sections done on /sup 28/Si + /sup 12/C and /sup 30/Si + /sup 2/C over a wide range of bombarding energie… more
Date: January 1, 1986
Creator: Harmon, B. A.; Shapira, D.; Stelson, P. H.; Burks, B. L.; Erb, K. A.; Shivakumar, B. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Energy conservation potential of Portland cement particle size distribution control

Description: The main objective of Phase 3 is to develop practical economic methods of controlling the particle size distribution of portland cements using existing or modified mill circuits with the principal aim of reducing electrical energy requirements for cement manufacturing. Because of its scope, the work of Phase 3 will be carried out in 10 main tasks, which will be discussed in this report.
Date: January 1, 1986
Creator: Tresouthick, S.W. & Weiss, S.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Geothermal research at the Puna Facility

Description: Chemical analyses were conducted on the flocculated silica samples obtained during previous field experiments at HGP-A on both flashed and unflashed brines to determine the composition of the recovered silica for specific constituents of the brine which seem to often be entrapped in the silica during the flocculation process. Metals added as flocculants to the brine were also analyzed in order to evaluate the ease or difficulty with which these can be removed from the precipitated silica under … more
Date: May 1, 1986
Creator: Chen, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Regeneration and recycle of spent oxide reduction solvent salts used in pyrochemical plutonium recovery operations at Los Alamos

Description: One method used at Los Alamos for producing plutonium metal is to chemically reduce the oxide with calcium metal in molten CaCl/sub 2/ at 850/sup 0/C. The solvent CaCl/sub 2/ from this reduction step is currently discarded as low-level radioactive waste because it is saturated with the reaction by-product, CaO. We have developed and demonstrated a molten salt technique for rechlorinating the CaO, thereby regenerating the CaCl/sub 2/ and incorporating solvent recycle into the batch PuO/sub 2/ re… more
Date: January 1, 1986
Creator: Fife, K. W.; Bowersox, D. F.; Simpson, J. J.; Davis, C. C.; Phillips, B. J. & McCormick, E. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Loss and excitation in single collisions of highly-stripped heavy ions with atoms

Description: Cross sections for projectile loss and excitation (LE) in single collisions of heavy ions with atoms have been measured for 15 to 460 MeV S, Ar, Ca, and V ions, with charge states varying from 12+ to 21+ in H/sub 2/, He, Ne, and Ar gas targets. The results indicate that K x-ray production takes place through excitation rather than loss of a 1s electron. An independent electron model appears to provide a reasonable description of LE for Li-like projectiles. However, there are also indications th… more
Date: January 1, 1986
Creator: Graham, W. G.; Bernstein, E. M.; Clark, M. W.; Oglesby, C. S.; Tanis, J. A.; Berkner, K. H. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Energy conservation potential of Portland cement particle size distribution control

Description: The main objective of Phase 3 is to develop practical economic methods of controlling the particles size distribution of portland cements using existing or modified mill circuits with the principal aim of reducing electrical energy requirements for cement manufacturing.
Date: January 1, 1986
Creator: Tresouthick, S.W. & Weiss, S.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Field study of tracer and geochemistry behavior during hydraulic fracturing of a hot dry rock geothermal reservoir

Description: This study presents tracer and geochemistry data from several hydraulic fracturing experiments at the Fenton Hill, NM, HDR geothermal reservoir. Tracers have been injected at various times during these tests: (1) initially, before any flow communication existed between the wells; (2) shortly after a flow connection was established; and (3) after the outlet flow had increased to its steady state value. An idealized flow model consisting of a combination of main fracture flow paths and fluid leak… more
Date: January 1, 1986
Creator: Robinson, Bruce A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Energy conservation potential of Portland Cement particle size distribution control

Description: The main objective of Phase 3 is to develop practical economic methods of controlling the particle size distribution of portland cements using exiting or modified mill circuits with the principal aim of reducing electrical energy requirements for cement manufacturing. Because of its scope, the work of Phase 3 will be carried out in 10 main tasks, which will be discussed in this report.
Date: January 1, 1986
Creator: Tresouthick, S.W. & Weiss, S.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effects of carbon dioxide attack on geothermal cement grouts

Description: Studies of carbonation of geotheirmal grouts have shown that the physical criteria recommended by the American Petroleum Institute do not apply for durability in CO/sub 2/-containing fluids. The high silica binders, normally considered desirable because of their high strengths and low permeability, become permeable when carbonated. This allows further attack on the grout, and if the fluids are undersaturated with CaCO/sub 3/, then rapid corrosion will occur. On the other hand, grouts which cont… more
Date: March 1, 1986
Creator: Milestone, N. B.; Kukacka, L. E. & Carciello, N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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