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in subjects: "Chemical Preparation"

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Methane oxidation over dual redox catalysts

Review and analysis of the literature data on electron transfer itself and electron transfer oxidation of alkyl radicals was done in order to understand the mechanism by which methyl radical can be oxidized to CH{sub 3}{sup +} and further substituted by OH{sup {minus}} to form methanol. This allowed to compare and classify the various possible reaction patterns, understand the mechanism and circumstances of operation of each of them and select those which can be involved in oxidation of methyl … more

Date: March 1, 1989

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

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Liquefaction of coals using ultra-fine particle, unsupported catalysts: In situ generation by rapid expansion of supercritical fluid solutions

The program objective is to generate ultra-fine catalyst particles (20 to 400 {Angstrom} in size) and quantify their potential for improving coal dissolution in the solubilization stage of two-stage catalytic-catalytic liquefaction systems. In the first quarterly report for this program the concept behind our approach was detailed, the structure of the program was presented, key technical issues were identified, preliminary designs were outlined, and technical progress was discussed. All progre… more

Date: September 1, 1991

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Methanation in catalyst-sprayed tube wall reactors: a review

The design and operation of catalyst-sprayed tube wall reactors for methanation are discussed. Reactor tubes were either coated on the inner surface or on the outer surface with a Raney nickel catalyst. A liquid coolant, which was opposite the catalyst-reactant gas-side, removed the heat of methanation. Catalyst performance, reactor operating conditions, spent catalyst analyses, and other results are presented for five PDU tests.

Date: September 1, 1980

Creator: Pennline, H. W.; Schehl, R. R.; Haynes, W. P. & Forney, A. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Novel duplex vapor-electrochemical method for silicon solar cells. Quarterly progress report No. 7, August 1, 1977--October 31, 1977

Silicon obtained by the SiF/sub 4/-Na reaction was analyzed by spark source mass spectrometry (SSMS). A partial listing of the results is given below. The concentration units in parentheses are ppM wt. B(0.1), Al(0.8), Ga(0.06), P(0.2), F(0.1), Na(1.0), V(0.04), Mo(0.3), Ti(2.0), Zr(2.0), Mn(0.1), Ni(2.0), Zn(0.01), Cu(20.0), Cr(11.0), Fe(55.0). An excellent starting material for silicon solar cells is obtained on the basis of the low levels of B, Al, Ga, P and As. The source of the Fe and Cr i… more

Date: December 1, 1977

Creator: Kapur, V.K.; Nanis, L. & Sanjurjo, A.

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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Low cost hydrogen/novel membranes technology for hydrogen separation from synthesis gas, Phase 1. [Palladium-silver/poly(etherimide), polysulfone/poly(dimethylsiloxane)/poly(ether-esteramide)composite membranes]

During this quarter, work continued on the development of high-flux palladium-silver membranes for the separation of hydrogen from carbon dioxide. Palladium-silver/poly(etherimide) composite membranes were prepared by a vacuum sputtering technique. The influence of different poly(etherimide) support membranes on the performance of palladium-silver membranes was investigated. All membranes tested showed a hydrogen/carbon dioxide selectivity lower than that of the uncoated poly(etherimide)/poly(d… more

Date: January 1, 1987

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Preliminary economic evaluation of the Alkox process

A new chemical process has been invented at Battelle Pacific Northwest Laboratories for converting alkanes to alcohols. This new chemistry has been named the Alkox Process.'' Pacific Northwest Laboratory prepared a preliminary economic analysis for converting cyclohexane to cyclohexanol, which may be one of the most attractive applications of the Alkox process. A process flow scheme and a material balance were prepared to support rough equipment sizing and costing. The results from the economic… more

Date: September 1, 1991

Creator: Silva, L.J.; Lilga, M.A.; Camaioni, D.M. & Snowden, L.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Thin film cadmium telluride solar cells. Final technical report, July 1, 1979-August 31, 1980

Efforts during this program have been directed to the construction of apparatus for the chemical vapor deposition of cadmium telluride films, the selection and preparation of substrates, the deposition and characterization of cadmium telluride films, and the fabrication and characterization of solar cells. Cadmium telluride films have been deposited on a number of substrates by the direct combination of cadmium and tellurium on the substrate surface at 500/sup 0/C or higher at rates of up to 0.… more

Date: August 1, 1980

Creator: Chu, T. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Silicon halide-alkali metal flames as a source of solar grade silicon. Second quarterly report, September 1--November 30, 1977

The experimental effort on this program has concentrated thus far on Na/SiCl/sub 4/ and K/SiCl/sub 4/ opposed jet diffusion flames in an evacuated reaction vessel; both reactants are supplied as vapors. The flames are self-igniting, fast burning and intensely chemiluminescent. Solid reaction products have been collected, separated by simple washing, and some preliminary analyses performed which indicate that the concentrations of most impurities in the reagents are reduced during the course of … more

Date: December 1, 1977

Creator: Miller, W.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Genes and gene expression: Localization, damage and control -- A multilevel and inter-disciplinary study

All projects are working toward a goal for describing the three dimensional nuclear topography in terms of relative spatial relationships among genes (specific DNA sequence). Methods are now being perfected to detect these genes, quantitatively and spatially, to perturb these genes specifically, and to measure the perturbation in order to assure specificity. We are developing methods to assay, after perturbation of the target DNA within living cells, whether or not only the target sequence are … more

Date: September 1, 1990

Creator: Ts'o, P.O.P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Synthesis of /sup 13/C-enriched carbohydrates as chiral synthons for labeled compounds

Methods have been developed to synthesize labeled chiral compounds from labeled carbohydrates. During the course of these investigations, we have adapted both chemical and enzymatic methods for the large-scale interconversion of labeled aldoses and ketoses. 6 refs.

Date: January 1, 1985

Creator: Walker, T. E.; Unkefer, C. J. & Ehler, D. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Quarterly technical progress report, October 1-December 30, 1983

Several new initiatives were begun in coal preparation, including a project to develop a liquid CO/sub 2/ coalescence process that will produce a superclean coal containing less than 1% ash. Another new project in this area is focusing on chemical coal cleaning for the removal of harmful trace elements, such as arsenic, lead, and zinc. Milestones were reached in both of our major electron beam flue gas cleanup projects. In the area of coal-water mixtures, our major industrial contracts are now … more

Date: April 1, 1984

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Removable foam encapsulants

This paper describes the use of two different expandable bead foams as solvent removable encapsulants; specifically they are polystyrene (STYROPOR BF-414, BASF Wyandotte) and a styrenemaleic anhydride copolymer (DYTHERM X214, ARCO/Polymers). These expandable bead foams are commercially available and normally used in insulating applications. However, they have been adapted to the unusual task of encapsulating sophisticated and expensive electronic hardware which requires a rework capability. The… more

Date: January 1, 1982

Creator: Wischmann, K.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Synthesis of high specific activity (1- sup 3 H) farnesyl pyrophosphate

The synthesis of tritiated farnesyl pyrophosphate with high specific activity is reported. trans-trans Farnesol was oxidized to the corresponding aldehyde followed by reduction with lithium aluminium tritide (5%-{sup 3}H) to give trans-trans (1-{sup 3}H)farnesol. The specific radioactivity of the alcohol was determined from its triphenylsilane derivative, prepared under very mild conditions. The tritiated alcohol was phosphorylated by initial conversion to an allylic halide, and subsequent trea… more

Date: August 1, 1991

Creator: Saljoughian, M.; Morimoto, H. & Williams, P. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Preparation and some properties of Cu-Li alloys containing up to 20 at. % Li

Lithium strongly segregates to the surface of Cu-Li alloys, thus substantially lowering the Cu sputtering yield relative to pure Cu. Use of Cu-Li limiters or divertors in tokamaks can therefore be expected to be beneficial in limiting high-Z plasma impurity influx. A large scale (100-200g) method for the preparation of Cu-Li alloys is described. Analysis reveals that on solidification from the melt stratification occurs which leads to compositional inhomogeneity. The results are discussed in th… more

Date: January 1, 1985

Creator: Mendelsohn, M.; Krauss, A. R. & Gruen, D. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Relationship between fabrication parameters and structural characteristics of sintered lithium orthosilicate

Lithium orthosilicate (Li/sub 4/SiO/sub 4/) powder was synthesized by the solid-state reaction of lithium oxide with amorphous silica, and the effects of fabrication parameters on the structural characteristics of the product were investigated. Processing considerations such as milling media, drying technique, calcination time and temperature, pressing behavior, sintering time and temperatures, and impurity concentration were addressed. The initial powder particle size was observed to be import… more

Date: February 1, 1988

Creator: Chu, C.Y.; Bar, K.; Singh, J.B.; Poeppel, R.B. & Billone, M.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Harvard-MIT research program in short-lived radiopharmaceuticals

This report presents research on radiopharmaceuticals. The following topics are discussed: antibody labeling with positron-emitting radionuclides; antibody modification for radioimmune imaging; labeling antibodies; evaluation of technetium acetlyacetonates as potential cerebral blood flow agents; and studies in technetium chemistry. (CBS)

Date: January 1, 1991

Creator: Adelstein, S.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Nuclear medicine program progress report for quarter ending December 31, 1991

This report presents information on (1) a new improved synthesis of carrier-free rhenium-188-labeled Re(V) dimercaptosuccinic acid (DMSA) complex as a potential therapeutic agent for treatment of thyroid medullary carcinoma; and (2) the synthesis and evaluation of a series of iodine-125-labeled analogues of altanserine for imaging of serotonin receptors.

Date: April 1, 1992

Creator: Knapp, F. F., Jr.; Ambrose, K. R.; Callahan, A. P.; McPherson, D. W.; Mirzadeh, S.; Srivastava, P. C. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Summaries of FY 1979 research in the chemical sciences

The purpose of this report is to help those interested in research supported by the Department of Energy's Division of Chemical Sciences, which is one of six Divisions of the Office of Basic Energy Sciences in the Office of Energy Research. Chemists, physicists, chemical engineers and others who are considering the possibility of proposing research for support by this Division wll find the booklet useful for gauging the scope of the program in basic research, and the relationship of their inter… more

Date: May 1, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

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/sup 18/F-4-fluoroantipyrine

The novel radioactive compound /sup 18/F-4-fluoroantipyrine having high specific activity which can be used in nuclear medicine in diagnostic applications, prepared by the direct fluorination of antipyrine in acetic acid with radioactive fluorine at room temperature and purifying said radioactive compound by means of gel chromatography with ethyl acetate as eluent is disclosed. The non-radioactive 4-fluoroantipyrine can also be prepared by the direct fluorination of antipyrine in acetic acid wi… more

Date: January 1, 1980

Creator: Shiue, Chyng-Ysnn & Wolf, Alfred P.

Item Type: Patent

Partner: UNT Libraries Government Documents Department

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Synthesis and characterization of a covalently bound self-assembled macrocycle monolayer thin film for nonlinear optical materials

Synthesis and characterization of covalently bound self-assembled, 5,10,15,20-Tetra(4-pyridyl)-21H,23H-porphine monolayer superlattices on various oxide surfaces such as fused silica, glass or silicon are described. The mono-molecular thin film structures are characterized by UV-visible ({lambda}{sub max} = 447 nm) and FTIR-ATR spectroscopy. In addition, X-ray photoelectron spectroscopy and secondary ion mass spectroscopy studies are used to confirm the formation of a self-assembled monolayer o… more

Date: January 1, 1992

Creator: Li, DeQuan; Swanson, B. I.; Robinson, J. M. & Hoffbauer, M. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Coal liquefaction catalyst development. Quarterly progress report No. 3, October 1-December 31, 1979

Catalytic baseline runs continued with HDS-1442A in order to improve our baseline statistics as well as to monitor batch reactor performance. Testing of several new catalyst formulations was completed. No promising candidates for testing in the continuous aging unit were identified. The new SRC-II slurry oil was evaluated as a hydrogen donor liquefaction solvent. Our data indicates that the SRC-II heavy distillate oil is not as effective a hydrogen donor solvent as the hydrogenated anthracene o… more

Date: January 1, 1980

Creator: Kim, D. K.; Pellet, R. J. & Mahoney, J. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development and radiotherapeutic application of /sup 211/At-labeled radiopharmaceuticals. Progress report, March 1, 1981-February 28, 1982

This project is concerned with developing the potential of alpha-emitting radionuclides as agents for radiotherapy. Alpha-emitters seem ideally suited for his application because their high linear energy transfer and short range permit the deposition of considerable energy in a very small volume of tissue. Unlike the beta particles of /sup 131/I which have a range of about 1 to 2 mm in tissue, 5 to 7 MeV alpha particles would traverse only a few cell diameters. Among the available alpha-emitter… more

Date: January 1, 1981

Creator: Adelstein, S.J.; Zalutsky, M. & Bloomer, W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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TATB dry amination fine particle process. Period covered: July--September 1977

A process was developed on the pilot plant scale which can be used to reproduce fine particle TATB by dry amination. A series of 10 batches, with each batch yielding from 15 to 20 kg was produced to evaluate the process. The total chlorine content of the batches was generally about 0.5 percent but one of the batches had a total chlorine content higher than expected (1.05 percent).

Date: January 1, 1977

Creator: Quinlin, W. T. & Locke, J. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department