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Potential effects of maternal contribution on egg and larva population dynamics of striped bass: Integrated individual-based model and directed field sampling

Description: We have used a bioenergetically-driven, individual-based model (IBM) of striped bass as a framework for synthesizing available information on population biology and quantifying, in a relative sense, factors that potentially affect year class success. The IBM has been configured to simulate environmental conditions experienced by several striped bass populations; i.e., in the Potomac River, MD; in Hudson River, NY; in the Santee-Cooper River System, SC, and; in the San Joaquin-Sacramento River S… more
Date: January 1, 1991
Creator: Cowan, J.H., Jr. (Maryland Univ., Solomons, MD (United States). Chesapeake Biological Lab.) & Rose, K.A. (Oak Ridge National Lab., TN (United States))
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Partner: UNT Libraries Government Documents Department
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Thermodynamics of natural and industrial waters

Description: The most effective general formulations of thermodynamic equations for multicomponent aqueous solutions are discussed with respect to various ranges of temperature, pressure and composition with emphasis on solutes important in natural or industrial waters. A familiar equation in molality and in excess Gibbs energy is very successful up to 300{degree}C and ionic strength 6 mol{center dot}kg{sup {minus}1}, and can often be extended to 350{degree}C or above at high pressure and in favorable cases… more
Date: August 1, 1991
Creator: Pitzer, K.S.
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Partner: UNT Libraries Government Documents Department
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Molecular interactions in dilute supercritical mixtures: Molecular dynamics investigation

Description: We performed a series of molecular dynamics simulations aimed at investigating the nature of the microstructure around solute molecules in a supercritical solvent, in the limit of infinite dilution (no solute-solute interactions). The choice of model system (pyrene in supercritical carbon dioxide) and state conditions (5--20 moles/liter; 37{degrees}C and 75{degrees}C) was done so as to match corresponding fluorescence experiments performed at Georgia Tech. 18 refs., 3 figs.
Date: January 1, 1991
Creator: Debenedetti, P.G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Research on oil recovery mechanisms in heavy oil reservoirs

Description: The goal of the Stanford University Petroleum Research Institute is to conduct research directed toward increasing the recovery of heavy oils. Presently, SUPRI is working in five main directions: To assess the influence of different reservoir conditions (temperature and pressure) on the absolute and relative permeability to oil and water and on capillary pressure; To evaluate the effect of different reservoir parameters on the in-situ combustion process. This project includes the study of the k… more
Date: January 1, 1991
Creator: Brigham, W.E.; Aziz, K. & Ramey, H.J. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Direct conversion of light hydrocarbon gases to liquid fuel

Description: The objective of this program is to investigate the direct conversion of light gaseous hydrocarbons, such as those produced during Fischer-Tropsch synthesis or as a product of gasification, to liquid transportation fuels via a partial oxidation process. The process will be tested in an existing pilot plant to obtain credible mass balances. Specific objectives to be met include determination of optimal process conditions, investigation of various processing options (e.g. feed injection, product … more
Date: January 1, 1991
Creator: Foral, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Elastic constants and the structural phase transition in La sub 2-x Sr sub x CuO sub 4

Description: Resonant ultrasound spectroscopy is used to measure the temperature dependence of all six elastic moduli of La{sub 2-x}Sr{sub x}CuO{sub 4}. A giant softening (> 50% reduction) in the in-plane shear modulus, c{sub 66}, is observed and is attributed to the tetragonal-orthorhombic structural phase transition in this material. This phase transition and the corresponding softening is examined with a simple anharmonic mechanical model and a macroscopic Ginsburg-Landau formalism exploiting the full sy… more
Date: January 1, 1991
Creator: Sarrao, J.L.; Lei, Ming; Stekel, A.; Bell, T.M.; Leisure, R. G.; Sham, L.J. et al.
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Partner: UNT Libraries Government Documents Department
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Reactivity of Young Chars via Energetic Distribution Measurements

Description: In this report, we present some preliminary work performed on the effect of CO{sub 2} partial pressure on temperature programmed desorption spectra from CO{sub 2}-oxidized chars. The following was accomplished during the reporting period: Temperature programmed desorption (TPD) experiments were conducted on oxidized resin and Wyodak coal char samples gasified under varying different CO{sub 2} partial pressures. The following observations were made: CO{sub 2} partial pressure can be an important… more
Date: January 1, 1991
Creator: Calo, J. M.; Zhang, L. H.; Rachel, W. G. & Lilly, W. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Static and dynamic spin fluctuations in the spin glass doping regime in La sub 2-x Sr sub x CuO sub 4+y

Description: We review the results of neutron scattering studies of the static and dynamic spin fluctuations crystals of La{sub 2-x}Sr{sub x}CuO{sub 4+{delta}} in the doping regime intermediate between the Neel and superconducting regions. In this regime the in-plane resistance is linear in temperature down to {approximately}80 K with a crossover due to logarithmic conductance effects at lower temperatures. The static spin correlations are well-described by a simple model in which the inverse correlation le… more
Date: January 1, 1991
Creator: Birgeneau, R.J.; Belk, N.; Kastner, M.A.; Keimer, B. (Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Physics); Endoh, Y. (Tohoku Univ., Sendai (Japan). Dept. of Physics); Erwin, R.W. (National Inst. of Standards and Technology, Gaithersburg, MD (United States)) et al.
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Partner: UNT Libraries Government Documents Department
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Magnetic multilayer interface anisotropy

Description: Ni/Mo and Ni/V multilayer magnetic anisotropy has been investigated as a function of Ni layer thickness, frequency and temperature. Variable frequency ferromagnetic resonance (FMR) measurements show, for the first time, significant frequency dependence associated with the multilayer magnetic anisotropy. The thickness dependence allows one to extract the interface contribution from the total anisotropy. Temperature dependant FMR (9 GHz) and room temperature magnetization indicate that strain bet… more
Date: January 1, 1991
Creator: Pechan, M. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermodynamics of the hydrodenitrogenation of carbazole

Description: A thermodynamic analysis, based on accurate experimental Gibbs energies of formation, was completed for the key hydrogen-consuming steps in the HDN reaction network for carbazole. The results were compared with literature reaction studies. The concept of crossover temperature'' is shown to be a valuable tool in the interpretation of literature reaction-study results. Methods of nitrogen removal from aromatic materials are discussed in light of the findings of the thermodynamic analysis. It is c… more
Date: October 1, 1991
Creator: Steele, W. V. & Chirico, R. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Solid electrolytes and impact-resistant ceramics

Description: In this proposal, we describe a program to exploit recent achievements in two distinct areas of materials science, both of them dependent on the independent motion of singly charged ions through an immobile matrix. The first is the area of non-crystalline solid electrolytes in which this laboratory has gained prominence over the past decade. The second is an area proposed for study in our previous proposal and now verified as a principle worthy of considerable further investigation: it involves… more
Date: August 1991
Creator: Angell, C. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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H sup minus temperature dependencies in a Penning surface-plasma source

Description: Simple analysis of the nearly-Maxwellian angular distribution of the ribbon H{sup {minus}} ions beams extracted from a long, narrow slit on the 8X source yields the H{sup {minus}} temperature, kT{sub H{minus}}. The derived kT{sub H{minus}} are 0.1--0.3 eV for a 2-A dc discharge and 0.7-1.3 eV for a 400-A pulsed discharge. Because this diagnostic method relies on simple electronic techniques, it allows rapid study of the dependencies of kT{sub H{minus}} on the source parameters, such as gas flow… more
Date: January 1, 1991
Creator: Smith, H. V. Jr.; Sherman, J. D.; Geisik, C. & Allison, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Temperature programmed desorption from LiAlO sub 2 treated with H sub 2

Description: Temperature programmed desorption (TPD) measurements have been made of H{sub 2}O and H{sub 2} desorption from LiAlO{sup 2} treated at 923 K with He-H{sub 2} mixtures containing 990, 495, and 227 vppm H{sub 2}. Desorptions were into sweep gases of pure He and into He-H{sub 2} mixtures. The H{sub 2}O and H{sub 2} desorption peaks were shown to be the sums of first order subpeaks which had reproducible desorption activation energy and pre-exponential terms. For H{sub 2}O desorption, the activation… more
Date: January 1, 1991
Creator: Fischer, A.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The utilization of bubble detector technology in the development of a Combination Area Neutron Spectrometer (CANS)

Description: The compact and relatively inexpensive Combination Area Neutron Spectrometer (CANS) should provide neutron spectral capabilities heretofore available only via complex set-ups and time-consuming, painstaking calculations. Some of its strong points include the measurement of neutron fluence and the need for only a single algorithm, with a single solution, regardless of the spectra. Because fluence, a real quantity, is the foundation of dose equivalent determination, the results of CANS should end… more
Date: January 1, 1991
Creator: Buckner, M.A. & Sims, C.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Combustion Research Program: Flame studies, laser diagnostics, and chemical kinetics

Description: We have made a detailed study of the care that must be taken to correctly measure OH radical concentrations in flames. A large part of these studies has concerned collisional quenching of hydride radical species (OH, NH, and NH{sub 2}), in particular the dependence upon rotational level and collision velocity (temperature). The results on OH and NH have shown unique and interesting behavior from the viewpoint of fundamental molecular dynamics, pointing to quenching often governed by collisions … more
Date: January 22, 1991
Creator: Crosley, D.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparison of eigenvalue computations for the Savannah River K Reactor using 5 and 7 digit dimensional and isotopic quantities

Description: A study was undertaken to characterize the reactivity temperature coefficient (RTC) behavior for the Savannah River K-Reactor pursuant to the safety review mandated by the Department of Energy (DOE) in August 1988. During the course of the investigation, it was found that the accuracy levels required in dimensional and isotopic quantities at elevated temperatures were much greater than was initially supposed and are typically used in reactor neutronics calculations. The codes involved do not au… more
Date: January 1, 1991
Creator: Durkee, J.W. Jr.; Mosteller, R.D.; Perry, R.T. & Sapir, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High-temperature plasticity in copper polycrystals

Description: A procedure for testing and analysis is described that elicits the material parameters for deformation at elevated temperatures and at strain rates high enough to make diffusion an unimportant mechanism. As a first step, a simple scaling procedure is used on continuous stress strain curves to reduce the data to essentially one curve; the differentiated, normalized hardening diagram. A unique curve of this kind is then assumed at the microscopic level: it reflects the mechanism of hardening and … more
Date: January 1, 1991
Creator: Chen, Shuh Rong & Kocks, U.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Preliminary examination of oil bonding at sand surfaces and its influence on hot water separation

Description: The efficiency of water-based separation of oil from sand particles is dependent on the nature of the oil-sand association and a preliminary examination of this bonding has been completed. The degree of hydration of the sand surface at the time of contact with oil was related to the subsequent efficiency of the oil-sand separation process. Variables which influence hot water separation were correlated by multiple linear regression, and a second order experimental model was obtained. The process… more
Date: January 1, 1991
Creator: Hupka, J.; Budzich, M. & Miller, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development of an experimental database and theories for prediction of thermodynamic properties of aqueous electrolytes and nonelectrolytes of geochemical significance at supercritical temperatures and pressures

Description: Volumetric measurements have been completed for CH{sub 4}, CO{sub 2}, and H{sub 2}S at temperatures from 25{degrees}C to 380{degrees}C and 2 or 3 pressures at each temperature. The H{sub 2}S and CO{sub 2} solutions are stored in aluminized mylar bags in PVC pipes with water surrounding the bags at a pressure of several atmospheres. The methane is stored in a one liter autoclave with a sliding teflon piston engaging the sides of the autoclave which separates the standard methane solution from th… more
Date: May 2, 1991
Creator: Wood, R.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Compact Fusion Advanced Rankine (CFARII) power cycle---Operating regimes

Description: Performance (cost/kWe and efficiency) of generic Compact Fusion Advanced Rankine (CFARII) power conversion is investigated for various working fluids, operating temperatures and pressures, and thermal power levels. A general conclusion is that good CFARII performance is found for a remarkably broad range of materials, temperatures, pressures and power levels, which gives considerable flexibility to future design studies which may apply CFARII energy conversion to specific fusion energy sources … more
Date: September 30, 1991
Creator: Logan, B. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A co-metabolic approach to groundwater remediation

Description: In support of the US Department of Energy's (DOE) Integrated Demonstration (Cleanup of Organics in Soils and Groundwater at Non-arid Sites) at the Savannah River Site (SRS), Oak Ridge National Laboratory (ORNL) and the University of Tennessee (UT) are involved in demonstrations of the use of methanotrophs in bioreactors for remediation of contaminated groundwater. In preparation for a field demonstration at ORNL's K-25 Site in Oak Ridge, Tennessee, ORNL is conducting batch experiments, is opera… more
Date: January 1, 1991
Creator: Palumbo, A. V.; Boerman, P. A.; Strandberg, G. W.; Donaldson, T. L.; Jennings, H. L.; Lucero, A. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Review of CERN heavy-ion physics

Description: Results from the heavy-ion experiments at the CERN SPS are reviewed in the context of possible formation and identification of a quark-gluon plasma (QGP).
Date: November 1, 1991
Creator: Odyniec, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The thermodynamic properties of benzothiazole and benzoxazole

Description: This research program, funded by the Department of Energy, Office of Fossil Energy, Advanced Extraction and Process Technology, provides accurate experimental thermochemical and thermophysical properties for key'' organic diheteroatom-containing compounds present in heavy petroleum feedstocks, and applies the experimental information to thermodynamic analyses of key hydrodesulfurization, hydrodenitrogenation, and hydrodeoxygenation reaction networks. Thermodynamic analyses, based on accurate in… more
Date: August 1, 1991
Creator: Steele, W. V.; Chirico, R. D.; Knipmeyer, S. E. & Nguyen, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Direct conversion of light hydrocarbon gases to liquid fuel

Description: The objective of this program is to investigate the direct conversion of light gaseous hydrocarbons, such as those produced during Fischer-Tropsch synthesis or as a product of gasification, to liquid transportation fuels via a partial oxidation process. The process will be tested in an existing pilot plant to obtain credible mass balances. Specific objectives to be met include determination of optimal process conditions, investigation of various processing options (e.g. feed injection, product … more
Date: January 1, 1991
Creator: Foral, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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