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Brookhaven highlights for fiscal year 1991, October 1, 1990--September 30, 1991

Description: This report highlights Brookhaven National Laboratory's activities for fiscal year 1991. Topics from the four research divisions: Computing and Communications, Instrumentation, Reactors, and Safety and Environmental Protection are presented. The research programs at Brookhaven are diverse, as is reflected by the nine different scientific departments: Accelerator Development, Alternating Gradient Synchrotron, Applied Science, Biology, Chemistry, Medical, National Synchrotron Light Source, Nuclea… more
Date: January 1, 1991
Creator: Rowe, M.S.; Cohen, A.; Greenberg, D.; Seubert, L. & Kuper, J.B.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photoinduced Charge Separation by Polymer-Bound Chromophores

Description: This project has examined the photodynamic behavior of water-soluble polymers that have covalently linked hydrophobic chromophores spaced along the chains. These polymeric systems have been examined for photoinduced charge separation with electron-accepting ions having different total charge. Focus has been on the excited singlet (S{sub 1}) state formed by laser flash absorption. The effects of pH and ionic strength -- factors that govern the conformational nature of the polymer in solution -- … more
Date: September 1, 1991
Creator: Rodgers, M. A. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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NQR-NMR studies of higher alcohol synthesis Cu-Co catalysts

Description: Copper and cobalt are the key elements in syngas conversion catalyst systems used for higher alcohol synthesis. Their proximity and synergy sensitively control the selectivity and efficiency of the process. It is believed that their outer electronic charge distribution which is responsible for their electrical and magnetic properties might be governing their catalytic properties also. To examine the correlation between catalytic and magnetic properties, a series of copper cobalt catalysts (Co/C… more
Date: January 14, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties

Description: Several new types of silicon-containing preceramic polymers, i.e., poly(diorganosilacetylene) and poly(diorganosilvinylene) have been synthesized with molecular weights from 10,000 to 120,000. These polymers could be thermally converted to SiC with a moderate to high char yields. Ready solubility and good processability made these types of polymers attractive in their applications to ceramics. The thermal polymerization of diethynyldiphenyl-silane, which was reported in 1968 to afford poly(diph… more
Date: October 7, 1991
Creator: Pang, Yi.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermodynamic model for calorimetric and phase coexistence properties of coal derived fluids

Description: On September 1, 1989 work was initiated on a project to extend the available vapor-liquid equilibrium (VLE) model for coal fluids to allow satisfactory predictions of excess enthalpies of coal liquids at high pressures. The available vapor liquid equilibrium model was developed with support from previous grant from DOE-PETC (Grant no. DE-FG22-89PC90541). The current project also involves measurement of some model compound VLE data and chromatographic characterization of coal liquids for distrib… more
Date: October 1, 1991
Creator: Kabadi, V. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The bioenergetics of salt tolerance

Description: The aim of this project was to try to understand the adaptive mechanisms that organisms develop in order to respond to a sudden transformation in their environment to a salt shock.'' To study this problem we used a fresh water oxygenic photosynthetic cyanobacterium known as Synecoccus 6311. This organism suffers injury after this sudden exposure to high concentrations of sodium chloride equivalent to or even higher than that in sea water. Yet they are able to re-establish their photosynthetic a… more
Date: January 1, 1991
Creator: Packer, L.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Complex temporal and spatial patterns in nonequilibrium systems

Description: Dynamical systems methods are being developed and used to characterize the formation and evolution of temporal and spatial patterns in systems maintained far from equilibrium. In particular, experiments and analyses are considering electrodeposition of fractal metallic clusters, pattern formation in reaction-diffusion systems, and the primary instabilities of some fluid flows. Novel reactors have been developed to search for chemical patterns (spatial variations in the chemical composition), an… more
Date: September 1, 1991
Creator: Swinney, H. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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(Hadamard Raman imaging)

Description: We have used newly developed holographic notch filters for obtaining both Stokes and anti-Stokes Raman images. The filters can be used as close as {plus minus}70 cm{sup {minus}1} from the Rayleigh line. We have demonstrated that they are insensitive to polarization, have 80% transmission across their clear apertures and block laser light by 10{sup 4}. The devices now have replaced sharp-cut glass filters on our microscope. We have successfully developed multispectral control and display softwar… more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Capillary liquid chromatography using laser-based and mass spectrometric detection

Description: The research performed during the past year has mainly focused on investigating and minimizing the problems listed below that limit the practical utility of these capillary electrokinetic separation techniques in chemical analysis. (1) Analyses are hindered by poor reproducibility. This is largely a result of complicated and irreproducible capillary wall-solute interactions that often result in adsorption and mobility changes. (2) While the Micellar Electrokinetic Capillary Chromatography techn… more
Date: January 1, 1991
Creator: Sepaniak, M.J. & Cook, K.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Cationically polymerizable monomers derived from renewable sources

Description: The objective of this project is to make use of products obtained from renewable plant sources as monomers for the direct production of polymers which can be used for a wide range of plastic applications. In this report is described progress in the synthesis and polymerization of cationically polymerizable monomers and oligomers derived from botanical oils, terpenes, natural rubber, and lignin. Nine different botanical oils were obtained from various sources, characterized and then epoxidized. … more
Date: October 1, 1991
Creator: Crivello, J. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Manual of analytical methods for the Industrial Hygiene Chemistry Laboratory

Description: This Manual is compiled from techniques used in the Industrial Hygiene Chemistry Laboratory of Sandia National Laboratories in Albuquerque, New Mexico. The procedures are similar to those used in other laboratories devoted to industrial hygiene practices. Some of the methods are standard; some, modified to suit our needs; and still others, developed at Sandia. The authors have attempted to present all methods in a simple and concise manner but in sufficient detail to make them readily usable. I… more
Date: August 1, 1991
Creator: Greulich, K. A. & Gray, C. E.
Item Type: Refine your search to only Report
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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Micro-scale mass-transfer variations during electrodeposition

Description: Results of two studies on micro-scale mass-transfer enhancement are reported: (1) Profiled cross-sections of striated zinc surfaces deposited in laminar channel flow were analyzed with fast-fourier transforms (FFT) to determine preferred striation wavelengths. Striation frequency increases with current density until a minimum separation between striae of 150 {mu}m is reached. Beyond this point, independent of substrate used, striae meld together and form a relatively smooth, nodular deposit. Su… more
Date: August 1, 1991
Creator: Sutija, D.P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Future aircraft and potential effects on stratospheric ozone and climate

Description: The purpose of this study is to extend the recent research examining the global environmental effects from potential fleets of subsonic and supersonic commercial aircraft. Initial studies with LLNL models of global atmospheric chemical, radiative, and transport processes have indicated that substantial decreases in stratospheric ozone concentrations could result from emissions of NO{sub x} from aircraft flying in the stratosphere, depending on fleet size and magnitude of the engine emissions. T… more
Date: October 1, 1991
Creator: Kinnison, D.E. & Wuebbles, D.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Object-oriented data handling system for an automated chemistry laboratory

Description: The environmental-remediation efforts at DOE complexes require characterizing problems at each site before cleanup action. Characterization will require the chemical analysis of millions of samples at a significant cost. Automation of the required chemical analyses methods provides a cost-effective solution. An object-oriented approach was deemed necessary to allow for modularization, maintainability, reusability, and flexibility of the software and hardware. Each chemical analysis method is im… more
Date: January 1, 1991
Creator: Medvick, P.A.; Mniszewski, S.M. & Beugelsdijk, T.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nonlinear optical properties of new KTiOPO sub 4 isostructures

Description: The atomic structures of the nonlinear optical materials potassium titanyl phosphate (KTiOPO{sub 4}, or KTP) and potassium titanyl arsenate (KTiOAsO{sub 4}) feature one-dimensional channels through which the potassium ions are relatively free to migrate. Ion exchange results when these materials are immersed in molten salts containing alkali metal ions. Sodium, lithium and silver all exchange readily for K{sup +} single crystals of both KTP and KTA to yield the exchanged derivatives Na{sub .95}… more
Date: January 1, 1991
Creator: Phillips, M. L. F.; Harrison, W. T. A. & Stucky, G. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Atomic structure of clusters through chemical reactions

Description: Techniques for the probing of isolated metal cluster structure through adsorbate binding patterns will be described. The saturation of clusters with reagents such as ammonia and nitrogen provides information on the number of preferred binding sites for these reagents. The dependence of this number on cluster size can suggest particular structural themes. The equilibrium reaction with water can be used to identify cluster sizes having especially enhanced binding for the water molecule. Again, th… more
Date: January 1, 1991
Creator: Riley, S.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Dynamics of H sub 2 elimination from unsaturated hydrocarbons

Description: State-of-the-art laser and molecular beam techniques are used to study the dynamics of H{sub 2} elimination from 1,4-cyclohexadiene and ethylene. Information on the transition state configurations and the dynamics of the dissociation processes for these reactions is reported. 152 refs., 54 figs., 12 tabs.
Date: February 1, 1991
Creator: Cromwell, E.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Influences of clouds and rain on the large-scale transport and deposition of sulfur

Description: This paper describes the application of a three-dimensional, global-scale Eulerian model with an explicit description of cloud and chemical processes. Simulation results describing the transport of sulfur from North America and Europe across the north Atlantic Ocean during a climatological July are presented. Wet deposition was found to contribute slightly more to total sulfur deposition than dry deposition, a feature explained by the large amounts of precipitation during this month. The wet de… more
Date: July 1, 1991
Creator: Luecken, D.J.; Berkowitz, C.M. & Easter, R.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Steroselective synthesis and application of L-( sup 15 N) amino acids

Description: We have developed two general approaches to the stereoselective synthesis of {sup 15}N- and {sup 13}C-labeled amino acids. First, labeled serine, biosynthesized using the methylotrophic bacterium M. extorquens AM1, serves as a chiral precursor for the synthesis of other amino acids. For example, pyridoxal phosphate enzymes can be used for the conversion of L-({alpha}-{sup 15}N)serine to L-({alpha}-{sup 15}N)tyrosine, L-({alpha}-{sup 15}N)tryptophan, and L-({alpha}-{sup 15}N)cysteine. In the sec… more
Date: January 1, 1991
Creator: Unkefer, C.J. (Los Alamos National Lab., NM (United States)) & Lodwig, S.N. (Centralia Coll., WA (United States). Div. of Science)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Research for Electric Energy Systems

Description: This report documents the technical progress in investigations. The first investigation is concerned with the measurement of magnetic fields in support of epidemiogical and in vitro studies of biological field effects. NIST cohosted a workshop on exposure and biological parameters that should be considered during the vitro studies with extremely low frequency (ELF) magnetic and electric fields. Also, equations were developed to predict the magnetic field in a parallel plate magnetic field expos… more
Date: June 1, 1991
Creator: Anderson, W.E. (ed.)
Item Type: Refine your search to only Report
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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Detection sensitivity of x-ray CT imaging for NDE of green-state ceramics

Description: Improved ceramic-processing methods that use pressure slip-casting and injection molding are being developed at Norton Advanced Ceramics, with a goal of producing reliable structural ceramics for advanced heat engines. Nondestructive evaluation (NDE) of ceramic parts at different stages of processing can provide useful diagnostic information to help improve processing techniques. For example, an evaluation of density gradients in as-cast green-body samples can be used to judge mold performance … more
Date: 1991~
Creator: Gopalsami, N.; Rizo, P.; Ellingson, W. A. & Tracey, D. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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