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On-line chemical composition analyzer development

Description: The energy consumed in distillation processes in the United States represents nearly three percent of the total national energy consumption. If effective control of distillation columns can be accomplished, it has been estimated that it would result in a reduction in the national energy consumption of 0.3%. Real-time control based on mixture composition could achieve these savings. However, the major distillation processes represent diverse applications and at present there does not exist a pro… more
Date: February 1, 1992
Creator: Roberts, M.J.; Garrison, A.A.; Muly, E.C. & Moore, C.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Raman microprobe investigation of molecular structure and organization in the native state of woody tissue

Description: Although the primary emphasis of our program has remained with the application of Raman spectroscopy to the study of native tissue, the scope of the work has been expanded to include a number of complementary approaches. These have included Solid State 13C NMR, autoradiography of radiolabeled woody tissue sections, and the generation of biomimetic tertiary aggregates which simulate states of aggregation characteristic of cell walls. Our Raman spectroscopic studies have resulted in progress in t… more
Date: August 1, 1989
Creator: Atalla, R.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surface electrochemical control for the fine coal and pyrite separation

Description: Ongoing work includes the characterization of coal pyrites, the floatability evaluation of typical US coal samples, the flotation behavior of coal pyrites, the electrochemical measurement of the surface properties of coal pyrites, and the characterization of species produced at pyrite surfaces.
Date: January 1, 1992
Creator: Hu, Weibai; Huang, Qinping; Zhu, Ximeng; Li, Jun; Bodily, D. M.; Liang, Jun et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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On-line analysis of chemical composition using an FT-Raman spectrometer in the near-ir

Description: Newly commercialized Fourier transform Raman spectroscopic instrumentation provides a simpler alternative for vibrational spectroscopic analysis. Instrument vendors currently design for laboratory use, but there are many potential process applications of these stable, easy to use instruments. Raman spectroscopy is highly suited to analysis of aqueous samples. Near infrared excitation minimized fluorescence interference and allows for remote operation via fiber optic probes. The Department of En… more
Date: January 1, 1992
Creator: Garrison, A.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vibrational Raman Characterization of Hard Carbon and Diamond Films

Description: Amorphous hard carbon'' and microcrystalline diamond films are being investigated and characterized using high-sensitivity and spatial-profiling Raman spectroscopy. The hard carbon'' films have broad Raman spectra with no diamond line while higher quality diamond films show only a single sharp diamond line. Features in the Raman spectra of the amorphous hard carbon'' films correlate with the rates of specific types of wear. Changes in the relative intensity of the Raman band near 1570 cm{sup {m… more
Date: January 1, 1991
Creator: Ager, Joel; Veirs, D. K.; Cho, Namhee; Rosenblatt, G. M. & Marchon, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Coherent anti-Stokes Raman scattering in benzene and nitromethane shock-compressed to 10 GPa

Description: The frequency shifts of the ring-stretching mode of shock-compressed liquid benzene and the CN stretching mode of nitromethane have been measured using coherent anti-Stokes Raman scattering. Shock pressures up to 11 GPa were achieved using a two-stage light gas gun. The frequency shifted Raman signal was generated using single pulse Nd:YAG and broadband-type lasers. 16 refs., 3 figs.
Date: January 1, 1985
Creator: Schmidt, S.C.; Moore, D.S.; Shaner, J.W.; Shampine, D.L. & Holt, W.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Preliminary report on fluid inclusions from halites in the Castile and lower Salado formations of the Delaware Basin, southeastern New Mexico. [Freezing-point depression]

Description: A suite of samples composed primarily of halite from the upper Castile and lower Salado Formations of the Permian Basin was selected from Waste Isolation Pilot Plant (WIPP) core for a reconnaissance study of fluid inclusions. Volume percent of these trapped fluids averaged 0.7% to 1%. Freezing-point depressions varied widely and appeared to be unrelated to fluid-inclusion type, to sedimentary facies, or to stratigraphic depth. However, because very low freezing points were usually associated wi… more
Date: September 1, 1985
Creator: Stein, C. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Textures and morphologies of chemical vapor deposited (CVD) diamond

Description: The textures, surface morphologies, structural perfection, and properties of diamond films grown by activated chemical vapor deposition (CVD) vary greatly with the growth conditions. The evolution of two commonly observed polycrystalline morphologies, which give rise to <110> textures, will be described as well as the development of four films grown to produce <100>, <111>, and near <100>'' textures with various combinations of growth facets. These films were grown to test models of texture dev… more
Date: January 1, 1991
Creator: Clausing, R. E.; Heatherly, L.; Horton, L. L.; Specht, E. D.; Begun, G. M. (Oak Ridge National Lab., TN (United States)) & Wang, Z. L. (Tennessee Univ., Knoxville, TN (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Raman Spectroscopy of Shocked Water

Description: We describe a new technique for recording spontaneous Raman spectra from molecules during the passage of strong shock waves. We have used this technique to study the OH-stretch band of liquid H/sub 2/O shocked to pressure up to 26 GPa and 1700 K. The shape of the band changes over the range 7.5-26 GPa, and is described well by a two-component mixture model, implying changes in the intermolecular coupling of shock compressed water molecules. We discuss the implications of the spectra on the mech… more
Date: August 1, 1985
Creator: Holmes, N. C.; Nellis, W. J.; Graham, W. B. & Walrafen, G. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Laser Raman Spectroscopy in studies of corrosion and electrocatalysis

Description: Laser Raman Spectroscopy (LRS) has become an important tool for the in-situ structural study of electrochemical systems and processes in recent years. Following a brief introduction of the experimental techniques involved in applying LRS to electrochemical systems, we survey the literature for examples of studies in the inhibition of electrode reactions by surface films (e.g., corrosion and passivation phenomena) as well as the acceleration of reactions by electro-sorbates (electrocatalysis). W… more
Date: January 1, 1988
Creator: Melendres, C.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Infrared and Raman investigation of rare-earth phosphate glasses for potential use as radioactive waste forms

Description: This project was designed to investigate the properties of the rare-earth phosphate glasses CeO{sub 2}-P{sub 2}O{sub 5} and Pr{sub 2}O{sub 3}-P{sub 2}O{sub 5} for potential use as radioactive waste glasses. The research involved determination of the glass-forming region, loading capacity, and optimum processing parameters of the glasses. Structural studies of the unloaded host glasses and glasses loaded with simulated waste elements were to be done using Raman, infrared and infrared reflection … more
Date: November 10, 1986
Creator: Morgan, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transient stress evolution and crystallization in laser-irradiated amorphous titania sol-gel films

Description: Amorphous TiO{sub 2} sol-gel films are irreversibly transformed to a crystalline anatase phase when heated to temperatures in excess of 575 K or subjected to intense pulsed or CW laser irradiation. The laser-induced transformation is initiated as a result of impurity absorption and subsequent heating, and results in densification and relative changes in compressive stress of the film. Isothermally annealed films exhibit a decrease in compressive stress as crystallization proceeds while an incre… more
Date: October 1, 1991
Creator: Exarhos, G.J.; Hess, N.J. (Pacific Northwest Lab., Richland, WA (United States)) & Wood, S. (Washington State Univ., Pullman, WA (United States). Dept. of Physics)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Coherent and spontaneous Raman spectroscopy in shocked and unshocked liquids

Description: Coherent and non-coherent Raman spectroscopy is being used to study the structure and energy transfer in molecular liquids at high pressures. Stimulated Raman scattering, coherent anti-Stokes Raman scattering, and Raman induced Kerr effect scattering measurements have been performed in liquid benzene and liquid nitromethane shocked to pressures up to 11 GPa. Frequency shifts were observed for the 992 cm/sup -1/ ring stretching mode of benzene and the 920 cm/sup -1/ CN stretching mode of nitrome… more
Date: January 1, 1985
Creator: Schmidt, S.C.; Moore, D.S.; Schiferl, D.; Chatelet, M.; Turner, T.P.; Shaner, J.W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Static high pressure study of nitric oxide chemistry: proposed mechanism for nitric oxide detonation. [Shock initiated detonation]

Description: The chemistry of nitric oxide under static high pressure conditions has been studied using diamond anvil cells and spectroscopic methods. Pressurized samples warmed rapidly to room temperature undergo facile disproportionation to form N/sub 2/O, N/sub 2/O/sub 3/, N/sub 2/O/sub 4/, and NO/sup +/NO/sub 3//sup -/. Nitric oxide maintained at 80 K is observed to react at ca. 2.5 GPa to form, dominantly, N/sub 2/, O/sub 2/, and NO/sup +/NO/sub 3//sup -/. The complex chemistry of nitric oxide is best … more
Date: January 1, 1985
Creator: Swanson, B. I.; Agnew, S. F. & Greiner, N. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vibrational spectroscopy of shock-compressed liquid CO

Description: Single-pulse, multiplex, coherent anti-Stokes Raman spectroscopy (CARS) was used to observe the vibrational spectra of liquid CO shock compressed to several pressures and temperatures up to 9.9 GPa and 2010 K. The experimental spectra were compared to synthetic spectra calculated using a semiclassical model for CARS intensities and estimated vibrational frequencies, peak Raman susceptibilities and Raman line widths. A comparison of these data with result in the isoelectronic and materially very… more
Date: January 1, 1991
Creator: Moore, D. S.; Schmidt, S. C.; Shaw, M. S. & Johnson, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of sorption interactions between organic and mineral phases of processed oil shale

Description: Minerals and organic compounds representative of oil shale processing wastes were analyzed for potential sorption interactions. The analysis consisted of Fourier Transform Infrared spectroscopy, high performance liquid chromatography, thermogravimetric and differential scanning calorimetry, and laser Raman spectroscopy. Montmorillonite clay was used as a representative of the smectites found in raw and spent shales, and hematite was used as a representative of iron oxide found in spent shales. … more
Date: November 1, 1987
Creator: Blanche, M. S. & Bowen, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Energy and technology review

Description: Three review articles are presented. The first describes the Lawrence Livermore Laboratory role in the research and development of oil-shale retorting technology through its studies of the relevant chemical and physical processes, mathematical models, and new retorting concepts. Second is a discussion of investigation of properties of dense molecular fluids at high pressures and temperatures to improve understanding of high-explosive behavior, giant-planet structure, and hydrodynamic shock inte… more
Date: October 1, 1983
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Non-destructive Identification of Individual Leukemia Cells by Optical Trapping Raman Spectroscopy

Description: Currently, a combination of technologies is typically required to assess the malignancy of cancer cells. These methods often lack the specificity and sensitivity necessary for early, accurate diagnosis. Here we demonstrate using clinical samples the application of laser trapping Raman spectroscopy as a novel approach that provides intrinsic biochemical markers for the noninvasive detection of individual cancer cells. The Raman spectra of live, hematopoietic cells provide reliable molecular fing… more
Date: March 5, 2007
Creator: Chan, J W; Taylor, D S; Lane, S; Zwerdling, T; Tuscano, J & Huser, T
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High-Resolution Structure of the Photosynthetic Mn4Ca Catalyst from X-ray Spectroscopy

Description: The application of high-resolution X-ray spectroscopy methods to study the photosynthetic water oxidizing complex, which contains a unique hetero-nuclear catalytic Mn4Ca cluster, are described. Issues of X-ray damage especially at the metal sites in the Mn4Ca cluster are discussed. The structure of the Mn4Ca catalyst at high-resolution which has so far eluded attempts of determination by X-ray diffraction, EXAFS and other spectroscopic techniques has been addressed using polarized EXAFS techniq… more
Date: August 1, 2007
Creator: Yachandra, Vittal; Yano, Junko; Kern, Jan; Pushkar, Yulia; Sauer, Kenneth; Glatzel, Pieter et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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AFM CHARACTERIZATION OF LASER INDUCED DAMAGE ON CDZNTE CRYSTAL SURFACES

Description: Semi-conducting CdZnTe (or CZT) crystals can be used in a variety of detector-type applications. CZT shows great promise for use as a gamma radiation spectrometer. However, its performance is adversely affected by point defects, structural and compositional heterogeneities within the crystals, such as twinning, pipes, grain boundaries (polycrystallinity), secondary phases and in some cases, damage caused by external forces. One example is damage that occurs during characterization of the surfac… more
Date: June 10, 2008
Creator: Hawkins, S; Lucile Teague, L; Martine Duff, M & Eliel Villa-Aleman, E
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Monitoring Dynamic Protein Expression in Single Living E. Coli. Bacterial Cells by Laser Tweezers Raman Spectroscopy

Description: Laser tweezers Raman spectroscopy (LTRS) is a novel, nondestructive, and label-free method that can be used to quantitatively measure changes in cellular activity in single living cells. Here, we demonstrate its use to monitor changes in a population of E. coli cells that occur during overexpression of a protein, the extracellular domain of myelin oligodendrocyte glycoprotein (MOG(1-120)) Raman spectra were acquired of individual E. coli cells suspended in solution and trapped by a single tight… more
Date: January 9, 2007
Creator: Chan, J W; Winhold, H; Corzett, M H; Ulloa, J M; Cosman, M; Balhorn, R et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Raman Spectroscopy and instrumentation for monitoring soil carbon systems.

Description: This work describes developments in the application of Raman scattering and surface-enhanced Raman scattering (SERS) towards the assessment/characterization of carbon in soil. In the past, the nonspecific total carbon mass content of soil samples has generally been determined through mass loss techniques and elemental analysis. However, because of the concern over CO{sub 2} buildup in the atmosphere and its possible role in the ''Greenhouse Effect,'' there is a need for better-defined models of… more
Date: December 8, 2003
Creator: Stokes, D.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cell-directed assembly on an integrated nanoelectronic/nanophotonic device for probing cellular responses on the nanoscale.

Description: Our discovery that the introduction of living cells (Saccharomyces cerevisiae) alters dramatically the evaporation driven self-assembly of lipid-silica nanostructures suggested the formation of novel bio/nano interfaces useful for cellular interrogation at the nanoscale. This one year ''out of the box'' LDRD focused on the localization of metallic and semi-conducting nanocrystals at the fluid, lipid-rich interface between S. cerevisiae and the surrounding phospholipid-templated silica nanostruc… more
Date: January 1, 2006
Creator: Brinker, C. Jeffrey; Dunphy, Darren Robert; Ashley, Carlee E. (University of New Mexico, Albuquerque, NM); Fan, Hongyou; Lopez, DeAnna (University of New Mexico, Albuquerque, NM); Simpson, Regina Lynn et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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