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in subjects: "37 Inorganic, Organic, Physical And Analytical Chemistry"

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Nonlinear optical properties of new KTiOPO sub 4 isostructures

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: Article

Partner: UNT Libraries Government Documents Department

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Spectroscopy of transition metal species in rare gas matrices. I. Vanadium metal. II. Sulfides. III. Carbonyl complexes. IV. Dinitrogen complexes. V. Homonuclear diatomic compounds

No Description Available.

Date: October 1, 1975

Creator: DeVore, T. C.

Item Type: Thesis or Dissertation

Partner: UNT Libraries Government Documents Department

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Application of pressurized ion exchange to separations of transplutonium elements

High-pressure ion exchange chromatography, used first for nucleic acid separations, was applied to the production of the heavier actinides, particularly the transcurium elements. Its use at the TRU plant is described. Future developments are considered briefly. (DLC)

Date: January 1, 1980

Creator: Campbell, D.O.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Wells 1/sup 0/ x 2/sup 0/ NTMS area, Nevada. Data report (abbreviated)

Surface sediment samples were collected at 1336 sites, at a target sampling density of one site per 13 square kilometers. Ground water samples were collected at 112 sites. Neutron activation analysis results are given for uranium and 16 other elements in sediments, and for uranium and 9 other elements in ground water and surface water. Mass spectrometry results are given for helium in ground water. Field measurements and observations are reported for each site. Data from ground water and surfac… more

Date: July 1, 1980

Creator: Cook, J. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Kinetics of the radiation-induced exchange reactions of H/sub 2/, D/sub 2/, and T/sub 2/: a review

Mixtures of H/sub 2/--T/sub 2/ or D/sub 2/--T/sub 2/ will exchange to produce HT or DT due to catalysis by the tritium ..beta.. particle. The kinetics of the reaction D/sub 2/ + T/sub 2/ = 2DT may play an important role in designing liquid or solid targets of D/sub 2/--DT--T/sub 2/ for implosion fusion, and distillation schemes for tritium cleanup systems in fusion reactors. Accordingly, we have critically reviewed the literature for information on the kinetics and mechanism of radiation-induce… more

Date: January 6, 1978

Creator: Pyper, J.W. & Briggs, C.K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Atomic structure of clusters through chemical reactions

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: Article

Partner: UNT Libraries Government Documents Department

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Simulation of ethylbenzene dehydrogenation in microporous catalytic membrane reactors

Current state-of-the-art inorganic oxide membranes offer the potential of being modified to yield catalytic properties. The resulting modules may be configured to simultaneously induce catalytic reactions with product concentration and separation in a single processing step. Processes utilizing such catalytically active membrane reactors have the potential for dramatically increasing yield of reactions which are currently limited by either thermodynamic equilibria, product inhibition, or kineti… more

Date: April 1, 1989

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Dynamics of H sub 2 elimination from unsaturated hydrocarbons

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: Report

Partner: UNT Libraries Government Documents Department

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Anion exchange of 58 elements in hydrobromic acid and in hydriodic acid

Anion exchange distributions of 58 elements have been measured from 0.1-8.7M HBr and from 0.1-7.4M HI onto three strong-base resins, 8 and 4% cross-linked and macroporous. Data were obtained by 16- to 18-h dynamic batch contacts. Anion exchange in these media is compared to that in HCl. The effect of resin cross-linkage is considerably greater in HI media than in HBr and HCl media. Examples are presented of potentially useful separations using HBr and HI media alone and in combination with HCl.

Date: February 1, 1978

Creator: Marsh, S. F.; Alarid, J. E.; Hammond, C. F.; McLeod, M. J.; Roensch, F. R. & Rein, J. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Neutron induced gamma spectrometry for on-line compositional analysis in coal conversion and fluidized-bed combustion plants

Nuclear techniques involving relatively penetrating radiation may offer the possibility of non-invasive, continuous on-line instrumental monitoring which is representative of the full process stream. Prompt gamma rays following neutron capture are particularly attractive because the penetrating power of the neutrons and the, typically several MeV, capture gammas makes possible interrogation of material within a pipe. We are evaluating neutron capture gamma techniques for this application, both … more

Date: January 1, 1977

Creator: Herzenberg, C. L.; O'Fallon, N. M.; Yarlagadda, B. S.; Doering, R. W.; Cohn, C. E.; Porges, K. G. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Excited-state proton-transfer kinetics in 1-naphthol, 1-naphthol-sulfonates, and organometallic complexes

The dissociation of 1-naphthol in aqueous solution occurs so rapidly that the fluorescence from the neutral form, ROH, has been previously described as completely extinguished or hardly noticeable. Apparently nearly all of the fluorescence originates from the naphtholate ion. This paper reports on the proton-transfer characteristics of a series of 1-naphthol compounds, and also reports preliminary data on excited-state proton transfer in an organometallic complex of ruthenium.

Date: July 1, 1980

Creator: Shapiro, S. L.; Winn, K. R. & Clark, J. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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The electronic structure of condensed molecular systems

We have reviewed some of the basic properties of the electronic structure of condensed molecular systems. For the rare-gas solids, we concentrated our discussion on changes in the ground- and excited-state crystal-atomic wave functions as calculated with an approximate theoretical method. Compression of these wave functions leads to a softening of the equation of state at high densities, which seems to account for much of the total many-body effects. This compression is a true many-body effect … more

Date: January 1, 1988

Creator: LeSar, R.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Trends in resonance ionization spectroscopy

The author reviews the history of resonance ionization spectroscopy and then comments on the delineations of RIS with reference to many related laser processes. The substance of the paper deals with the trends in RIS and especially how the needs for sensitive analytical methods have overshadowed the orginal plan to study excited species. 9 refs., 1 fig.

Date: January 1, 1986

Creator: Hurst, G.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Isotopically selective, Doppler-free, saturation spectroscopy of lutetium isotopes via resonance ionization mass spectrometry

A new technique utilizing RIMS to obtain very high resolution atomic spectra with isotopic selectivity has been demonstrated. This technique allows the precise determination of HF splitting constants, limited only by the transition's natural linewidth. In addition, it is also feasible with this technique to accurately determine atomic isotope shifts. The exact determination of HF component line positions provides data for isotopically selective ionization which, in turn, will increase RIMS' dyn… more

Date: January 1, 1988

Creator: Fearey, B. L.; Parent, D. C.; Keller, R. A. & Miller, C. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Design requirements for uranium ion exchange from acidic solutions in a fluidized system

A fluidized, countercurrent ion-exchange system was developed, operated, and evaluated by the Bureau of Mines in support of its objective to help assure an adequate uranium supply for future national needs. The system consisted of integrated multiple-compartment absorption and elution columns in which the solution flows are continuous, except for short periods when resin increments are withdrawn. The exchange of uranyl sulfate between a simulated acid-leach-uranium solution and a strong-base, i… more

Date: January 1, 1974

Creator: Traut, D.E.; Nichols, I.L. & Seidel, D.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Experimental investigation of the chemistry of excited states of rare gases. First quarterly progress report, October 15, 1977--January 15, 1978

The quenching of XeF(B) was studied using the steady-state photolysis of XeF/sub 2/ as the source of XeF(B). The product states from the sensitized reaction of Xe(/sup 3/P/sub 1/) with Cl/sub 2/ and COCl/sub 2/ also were studied. The new XeF(B) quenching rate constants are described. The pulsed laser induced fluorescence technique was used to measure radiative lifetimes and two-body quenching rate constant (with Ar) for the low energy Xe(6p)* states. Serious signal/noise problems for the lowest… more

Date: February 1978

Creator: Setser, D. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Uranium hexafluoride: Safe handling, processing, and transporting: Conference proceedings

This conference seeks to provide a forum for the exchange of information and ideas of the safety aspects and technical issue related to the handling of uranium hexafluoride. By allowing operators, engineers, scientists, managers, educators, and others to meet and share experiences of mutual concern, the conference is also intended to provide the participants with a more complete knowledge of technical and operational issues. The topics for the papers in the proceedings are widely varied and inc… more

Date: January 1, 1988

Creator: Strunk, W.D. & Thornton, S.G. (eds.)

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Evaluation of the radionuclide concentrations in soil and plants from the 1975 terrestrial survey of Bikini and Eneu Islands

In June 1975 a radiological survey was conducted of the terrestrial environment of Bikini and Eneu islands (Bikini Atoll) to evaluate the potential radiation dose to the returning Bikini population. In this report, we present measurements of the radionuclide concentration in soil profiles and in dominant species of edible and nonedible, indicator plants. The use of these data to derive relationships to predict the plant uptake of radionuclides from soil is described. Approximately 620 soil and … more

Date: January 21, 1977

Creator: Colsher, C. S.; Robison, W. L. & Gudiksen, P. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Steroselective synthesis and application of L-( sup 15 N) amino acids

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: Article

Partner: UNT Libraries Government Documents Department

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Research for Electric Energy Systems

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: Report

Partner: UNT Libraries Government Documents Department

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Methane oxidation over dual redox catalysts

The objective of this research is to develop approaches to direct catalytic oxidation of methane over oxides that are doubly doped with transition metal ions. The desired process aims at employing a double redox mechanism, where one redox couple is utilized for activation of oxygen and another for the trapping of CH{sub 3} radicals. The methyl radicals can either recombine, giving C{sub 2} hydrocarbons, or be converted, via electron transfer reaction, to carbocations. The latter species can rea… more

Date: September 1, 1989

Creator: Klier, Kamil; Herman, Richard G. & Sojka, Zbigniew

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Reactivity of Young Chars via Energetic Distribution Measurements

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: Report

Partner: UNT Libraries Government Documents Department

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Automation of the National Water Quality Laboratories, U. S. Geological Survey. I. Description of laboratory functions and definition of the automation project

In January 1976, the Water Resources Division of the U.S. Geological Survey asked Lawrence Livermore Laboratory to conduct a feasibility study for automation of the National Water Quality (NWQ) Laboratory in Denver, Colorado (formerly Denver Central Laboratory). Results of the study were published in the Feasibility Study for Automation of the Central Laboratories, Lawrence Livermore Laboratory, Rept. UCRL-52001 (1976). Because the present system for processing water samples was found inadequat… more

Date: July 1, 1977

Creator: Morris, W.F. & Ames, H.S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Radiation effects and metalloproteins studied by x-ray photoelectron spectroscopy

X-ray photoelectron spectroscopy (XPS) is used to study the bonding structure at the iron site of cytochrome c and the bonding of rare earth ions to the phosphate oxygens of ATP. Radiation effects are studied on several amino acid and simple peptide model systems. The emission spectrum of the x-ray source is calculated from literature references. The distributions of photon energy as a function of photon frequency and as a function of take-off angle are obtained. From these distributions, the r… more

Date: July 1, 1975

Creator: Wurzbach, J.A.

Item Type: Report

Partner: UNT Libraries Government Documents Department