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A small low energy cyclotron for radioisotope measurements

Description: Direct detection of {sup 14}C by accelerator mass spectrometry has proved to be a much more sensitive method for radiocarbon dating than the decay counting method invented earlier by Libby. A small cyclotron (the cyclotrino'') was proposed for direct detection of radiocarbon in 1980. This combined the suppression of background through the use of negative ions, which had been used effectively in tandem accelerators, with the high intrinsic mass resolution of a cyclotron. Development of a small e… more
Date: November 1, 1989
Creator: Bertsche, Kirk Joseph
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Review of monitoring instruments for transuranics in fuel fabrication and reprocessing plants. A progress report to the physical and technological programs, Division of Biomedical and Environmental Research, U. S. Energy Research and Development Administration

Description: A comprehensive review of the monitoring instruments for transuranic elements released from nuclear fuel fabrication and reprocessing plants has been compiled. The extent of routine operational releases has been reviewed for the light water reactor (LWR) fuel cycle (including plutonium recycle), the breeder reactor fuel cycle, and the high-temperature gas cooled reactor (HTGR) fuel cycle. The stack monitoring instrumentation presently in use at the various fabrication and reprocessing plants ar… more
Date: November 16, 1976
Creator: Kordas, J. F. & Phelps, P. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(. pi. ,K) production of hypernuclei

Description: Since a single {Lambda} behaves as a distinguishable particle in the nucleus, it can occupy any single-particle orbit in the {Lambda}-nucleus average field. Well-defined series of peaks corresponding to nodeless single-particle states have been identified in heavy nuclei using the ({pi}{sup +},K{sup +}) reaction at Brookhaven. The spacings of the {Lambda} single-particle levels for a given A constrain both the radius and the depth of the {Lambda} potential well. It can be seen that a Woods-Saxo… more
Date: November 1990
Creator: Millener, D. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sequential low-temperature depolymerization and liquefaction of US coals

Description: Suitable conditions for high-yield conversion of a Pittsburgh [number sign]8 (Pennsylvania) coal sample, supplied by the Argonne program and designated below as PB(PA) coal, were previously developed (see Progress Report no. 4, pp. 3--15; and Progress Report no. 6, pp- 3--4). In some recent experiments, the yield of low-boiling hydrocarbon fuel fractions (gasoline, kerosene and gas oil; b.p. up to 325[degrees]C) from this coal was further increased to a level of 70--72 wt % (MAF basis). The mai… more
Date: November 1, 1988
Creator: Shabtai, J. S. & Wiser, W. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hypernuclear structure using the (. pi. ,K)

Description: The result and theoretical interpretation of ({pi}{sup +},K{sup +}) experiments carried out at Brookhaven are summarized. Shell-model calculations are used to illustrate the precise spectroscopic studies of {Lambda} hypernuclei which could be carried out using the intense pion beams and good energy resolution for ({pi}{sup +},K{sup +}), ({pi}{sup +},K{sup +}{gamma}) and possibly ({pi}{sup {minus}},K{sup 0}) reactions at PILAC. 24 refs., 4 figs.
Date: November 1, 1990
Creator: Millener, D. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiopharmaceuticals in PET, Progress and Promise

Description: It is the intention of this presentation to focus on the current state of radiopharmaceuticals for PET and where this is leading us. PET radiopharmaceuticals can be broken down into perhaps seven categories at present with each being applicable to a different aspect of human biochemistry. These are: metabolic probes, neurochemical probes, enzyme probes, ion channel blockers, blood flow agents, ethical drugs and other positron emitters. 7 refs.
Date: November 1, 1988
Creator: Wolf, A. P. & Fowler, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Two dimensional NMR and NMR relaxation studies of coal structure

Description: This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inve… more
Date: November 25, 1992
Creator: Zilm, K.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nuclear waste management quarterly progress report, April--June 1978

Description: Work is reported in the following: decontamination and densification of chop-leach cladding residues; monitoring methods for particulate and gaseous effluents from waste solidification processes; TRU waste immobilization; krypton solidification; /sup 14/C and /sup 129/I fixation; system studies; safety studies; waste isolation safety assessment; well logging instrumentation for shallow land burial; monitoring and physical characterization of unsaturated zone transport; detection and characteriz… more
Date: November 1, 1978
Creator: Platt, A.M. & Powell, J.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coal Liquefaction Process Streams Characterization and Evaluation: The Use of Selective Chemical Reactions and Carbon NMR Spectroscopy in the Speciation and Quantification of Oxygen Functional Groups in Coal Resids

Description: This study demonstrated the feasibility of using phase-transfer methylation reactions for the derivatization of hydroxyl functionalities and single-electron transfer reactions to cleave ether groups in distillation resid materials derived from direct coal liquefaction. [sup 13]C-NMR was used to analyze the reaction products. It was demonstrated that the techniques can be used to speciate and quantify about half of the oxygen in resids. The remaining half of the oxygen is presumed to be present … more
Date: November 1, 1992
Creator: Stock, L. M. & Cheng, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Coal liquefaction process streams characterization and evaluation: [sup 13]C-NMR analysis of CONSOL THF-soluble residual materials from the Wilsonville coal liquefaction process

Description: This study demonstrated the feasibility of using CP/MAS [sup 13]C-NMR spectroscopy for the chemical structural examination of distillation resid materials derived from direct coal liquefaction. A set of twelve carbon skeletal-structure parameters and eight molecular structural descriptors were derived from the NMR data. The technique was used previously to determine these parameters for coal and char, and in the construction of a coal pyrolysis model. The method was applied successfully to the … more
Date: November 1, 1992
Creator: Solum, M. S. & Pugmire, R. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Water use, productivity and interactions among desert plants

Description: Water plays a central role affecting all aspects of the dynamics in aridland ecosystems. Productivity, stability, and competitive interactions among ecosystem components within aridlands are key processes related directly to water in deserts. The ecological studies in this project revolve around one fundamental premise: that integrated aspects of plant metabolism provide insight into the structure and function of plant communities and ecosystems. While it is difficult to extrapolate from instan… more
Date: November 17, 1992
Creator: Ehleringer, J.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Analysis of stirred-tank carbonation reactors. [Removal of /sup 14/CO/sub 2/ by reaction with Ca(OH)/sub 2/]

Description: The removal of CO/sub 2/ from air in a calcium hydroxide slurry-agitated reactor was investigated to aid the design of such vessels. Gas-liquid interfacial areas were calculated using theoretical rate expression and experimental data at specific operating conditions. A correlation for interfacial areas was then determined as a function of impeller speed, impeller diameter, gas flow rate, and concentration of the slurry. Decontamination factors were also determined.
Date: November 21, 1978
Creator: Sheppard, N.F.; Rizo-Patron, R.C. & Sun, W.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Molecular laser studies in the 7-16. mu. m range. Final report, October 1, 1976-September 30, 1977

Description: Exploratory research efforts on obtaining 7.7, 8.6, 12 and 16 ..mu..m wavelength radiation by means of multi-photon pumping of molecular gases and by means of metal oxidation chemical lasers are described. A strong 822.6534 cm/sup -1/ lasing signal was obtained from NH/sub 3/ by a two photon pumping process to excite the 2..nu../sub 2/ a(53) energy level, with lasing taking place to ..nu../sub 2/ s(63). The pump lines were the P/sub 9/(24) line of /sup 12/CO/sub 2/ and the P/sub 9/(8) line of /… more
Date: November 1, 1977
Creator: Coleman, P.D.; Adams, R.; Kim, D. & Leap, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tritium, carbon-14, and iodine-129 as indicators for localized vertical recharge along an anticline in the Columbia River Basalts using a decay-corrected mixing model

Description: Tritium, /sup 14/C, and /sup 129/I in groundwater samples are used to demonstrate vertical recharge and measure flow velocity in the fractured and faulted Umtanum Ridge-Gable Mountain acticline, within the Columbia River Basalts, at a sampling site about 6 mi northeast of the proposed high-level nuclear waste repository at the Hanford Site, Washington State. Mixing model calculations yield an apparent downward migration rate of 15 to 19 ft/yr through a sequence of aquifers in the Wanapum Basalt… more
Date: November 1, 1987
Creator: Hall, S. H.; Johnson, V. G. & Early, T. O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Inhibition of retrogressive reactions in coal/petroleum co-processing

Description: The overall objective of this project is to develop a fundamental understanding of the reactions occurring at the onset of coke formation during the co-processing of coals with petroleum residua. The specific objectives include examination of chemical components, or groups of components, in coals and petroleum feedstocks to quantify and rank the effects of these components in retarding or enhancement of coke formation. The work involves bench scale reactions in microautoclaves, supplemented by … more
Date: November 1, 1991
Creator: Schobert, H.H. & Tomic, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling of gaseous sup 14 CO sub 2 release from perforations in spent fuel disposal containers

Description: The potential release of gaseous {sup 14}CO{sub 2} from small perforations in spent fuel containers has been evaluated as a function of temperature, hole size, effective porosity of corrosion products within the hole, and time, based on the waste package design parameters and environmental conditions described in the Yucca Mountain Site Characterization Report (SCP). The SCP does not specify initial fill gas (argon) pressure and temperature. It is shown that, if significant {sup 14}C oxidation … more
Date: November 1, 1991
Creator: Pescatore, C. & Sullivan, T.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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NMR investigation of dynamic processes in complexes of nickel(II) and zinc(II) with iminodiacetate, n-methyliminodiacetate and n-ethyliminodiacetate

Description: Analysis of oxygen-17 bulk water relaxation rates with an aqueous solution of 1:1 Ni(II):ida reveals that two rate-limiting processes are involved with solvent exchange. Analysis of carbon-13 longitudinal relaxation rates of the bis-ligand complexes with zinc(II) are used to determine molecular tumbling rates and methyl rotation rates. The carbon-13 transverse relaxation rates for the carbons in the bis-ligand complex with Ni(II) are adequately fitted to the Solomon-Bloembergen equation. Three … more
Date: November 1, 1985
Creator: Wagner, M.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization and properties of plasma polymerized 2-vinylpyridine

Description: The chemical structure, aging, thermal, and adhesive behavior of plasma-deposited 2-vinylpyridine has been investigated. The molecular structure of the plasma polymer is significantly different from the conventional, linear polymer and is strongly dependent on plasma reactor variables. Additional cyano, methyl, and olefinic groups were identified in the plasma polymer, and aromaticity retention was reduced at the more severe (low pressure, high rf power) reactor conditions studied. Post-deposit… more
Date: November 1, 1979
Creator: Bieg, K. W.; Ottesen, D. K. & Brower, K. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nuclear waste management. Quarterly progress report, July-September 1979

Description: Research is reported on: decontamination and densification of chop-leach cladding residues, monitoring of effluents from waste solidification, TRU waste mobilization, Kr solidification, /sup 14/C and /sup 129/I fixation, waste management system and safety studies, waste isolation safety assessment, logging systems for shallow land burial, unsaturated zone transport, mobile organic complexes of fission products, electropolishing for surface decontamination of metals, and decontamination and deco… more
Date: November 1, 1979
Creator: Platt, A.M. & Powell, J.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mercury in mussels of Bellingham Bay, Washington, (USA)

Description: Laboratory experiments demonstrated the existence of metallothionein-like, low molecular weight, mercury-binding proteins in the marine mussel Mytilus edulis. Relatively large quantities of mercury were associated with such proteins in gills and digestive gland, the organs of interest in the present study. /sup 14/C-incorporation indicated induction of the protein in gills, but not in digestive gland. Mercury in digestive gland may have bound to existing metal-binding proteins. Short-term incor… more
Date: November 1, 1978
Creator: Roesijadi, G.; Drum, A.S. & Bridge, J.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Compatibility of technologies with regulations in the waste management of H-3, I-129, C-14, and Kr-85. Part II. Analysis

Description: Waste forms of /sup 3/H, /sup 129/I, /sup 14/C, and /sup 85/Kr separated from fuel reprocessing streams and procedures for managing them were analyzed regarding compliance with regulations. Transportation of these wastes in certain DOT-specification packagings would be permissible, but some of these packagings may not be acceptable in some disposal situations. Transportation of gaseous /sup 85/Kr in a currently certified cylinder is possible, but a fuel reprocessor may wish to ship larger quant… more
Date: November 1, 1983
Creator: Trevorrow, L.E.; Kolba, V.M.; Vandegrift, G.F. & Steindler, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Coal liquefaction process streams characterization and evaluation

Description: This study clearly demonstrated the usefulness of liquid- and solid-state {sup 13}C- and {sup 1}H-NMR for the examination of process-derived materials from direct coal liquefaction. The techniques can provide data not directly obtainable by other methods to examine the saturation of aromatic rings and to determine the modes of hydrogen utilization during coal liquefaction. In addition, these methods can be used to infer the extent of condensation and retrograde reactions occurring in the direct… more
Date: November 1, 1991
Creator: Miknis, F.P. (Western Research Inst., Laramie, WY (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nuclear magnetic resonance studies of the regulation of the pentose phosphate pathway

Description: The goal of this work is to investigate the potential for and limitations of in vivo nuclear magnetic resonance (NMR) spectroscopy for quantitation of glucose flux through the pentose phosphate pathway (shunt). Interest in the shunt is motivated by the possibility that its activity may be greatly increased in cancer and in the pathological states of cardiac and cerebral ischemia. The ability to dynamically monitor flux through the pentose shunt can give new knowledge about metabolism in patholo… more
Date: November 1, 1991
Creator: Bolo, N.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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