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Engineering Development of Lithium/Metal Sulfide Battery Technology for Vehicle Propulsion : Summary Report, October 1977- September 1978

Description: The research, development, and management activities done in preparation for in-vehicle testing of engineering-scale lithium/metal sulfide batteries are described. These activities were carried out at Argonne National Laboratory (ANL) from October 1977 to September 1978. Over the past year, lead--acid batteries were tested both in the laboratory and in a Renault automobile. The data obtained from these tests will be used to assess the performance of lithium/metal sulfide batteries. Testing of a 40 kWh lithium/metal sulfide battery in a vehicle is planned for early 1979. The equipment needed to evaluate the performance of this battery was designed and fabricated. Testing of this equipment is expected to begin at the end of 1978. In order to carry out the above in-vehicle test, the lithium/metal sulfide battery must have a thermally efficient case and a charger. Construction of such a case is in progress. A portable charger/equalizer that has the capability of charging up to six lithium/metal sulfide cells was fabricated.
Date: March 1979
Creator: Barney, Duane L.; Chilenskas, A. A.; DeLuca, W. H.; Hayes, E. R.; Hornstra, F.; Farahat, M. K. et al.
Partner: UNT Libraries Government Documents Department

The Heat of Formation of Thorium Sesquisulfide

Description: Abstract: "The heat of solution of thorium sesquisulfide was determined in 6.000 molar HCl at 25 C to ascertain the stability of the thorium (III) halides. The molal heat of formation of Th2S3 from rhombic sulfur and crystalline thorium is calculated as 258.6 kcal."
Date: April 7, 1953
Creator: Eyring, LeRoy & Westrum, Edgar F., Jr.
Partner: UNT Libraries Government Documents Department

Organusulfur Catalysis With Reduced Molybdenum Sulfides Containing the Mo6S8 Cluster

Description: Industrial synthesis of sulfur-containing organic chemicals basically focuses on the broad categories of mercaptans (thiols), alkylsulfides (thioethers), polysulfides, and thiophenes. Of the organo-sulfur compounds produced, by far the most important in terms of quantities produced is methyl mercaptan (methanethiol or MeSH), which is produced mainly for the downstream production of methionine and methanesulfonyl chloride. Higher thiols are also used in the manufacture of rubber and plastics as polymerization regulators, chain transfer agents, or initiators. Other important organosulfur chemicals are dimethyl sulfide (DMS) and dimethyl disulfide (DMDS), both of which are used extensively for presulfiding of industrial hydroprocessing catalysts, and substituted thiophenes which are used as intermediates for production of agrochemicals, dyes, and pharmaceuticals. Thiols are produced commercially at the rate of about 10{sup 4} ton/yr from hydrogen sulfide (H{sub 2}S) and alcohols or olefins, using homogeneous free-radical synthesis, or heterogeneous catalysts based on solid acids or supported metal oxides and/or sulfides. Despite this large production rate, and the industrial importance of the organosulfur compounds, only limited research has been devoted to the development of new catalytic materials for their synthesis. Additionally, for most organosulfur catalytic reactions, only limited information exists about reaction mechanisms, active sites, adsorbed surface species, and especially the nature of the catalysts under reaction conditions.
Date: August 27, 2002
Creator: Paskach, Thomas Jay
Partner: UNT Libraries Government Documents Department

Selective Facet Reactivity During Cation Exchange in Cadmium Sulfide Nanorods

Description: The partial transformation of ionic nanocrystals through cation exchange has been used to synthesize nanocrystal heterostructures. We demonstrate that the selectivity for cation exchange to take place at different facets of the nanocrystal plays an important role in determining the resulting morphology of the binary heterostructure. In the case of copper I (Cu+) cation exchange in cadmium sulfide (CdS) nanorods, the reaction starts preferentially at the ends of the nanorods such that copper sulfide (Cu2S) grows inwards from either end. The resulting morphology is very different from the striped pattern obtained in our previous studies of silver I (Ag+) exchange in CdS nanorods where non-selective nucleation of silver sulfide (Ag2S) occurs. From interface formation energies calculated for several models of epitaxialconnections between CdS and Cu2S or Ag2S, we infer the relative stability of each interface during the nucleation and growth of Cu2S or Ag2S within the CdS nanorods. The epitaxial connections of Cu2S to the end facets of CdS nanorods minimize the formation energy, making these interfaces stable throughout the exchange reaction. However, as the two end facets of wurtzite CdS nanorods are crystallographically nonequivalent, asymmetric heterostructures can be produced.
Date: December 18, 2008
Creator: Sadtler, Bryce; Demchenko, Denis; Zheng, Haimei; Hughes, Steven; Merkle, Maxwell; Dahmen, Ulrich et al.
Partner: UNT Libraries Government Documents Department

Polymer pendant crown thioethers for removal of mercury from acidic wastes

Description: Removal and immobilization of mercury ions from industrial waste streams is a difficult and expensive problem requiring an efficient and selective extractant that is resistant to corrosive conditions. We have now developed an acid-resistant thiacrown polymer that has potential utility as a selective and cost-effective Hg<sup>2+</sup> extractant. Copolymerization of a novel C-substituted thiacrown, N,N-(4-vinylbenzylmethyl)-2-aminomethyl- ,4,&l 1,14- pentathiacycloheptadecane, with DVB (80% divinylbenzene) using a radical initiator generated a highly cross-linked polymer containing pendant thiacrowns. Mercury extraction capabilities of the polymer were tested in acidic media (pH range: 1.5 to 6.2) and the extraction of Hg<sup>2+</sup> was determined to be 95<sup>+</sup>% with a mixing time of 30 minutes. The thiacrown polymer was also determined to be selective for Hg*+, competing ions such as Pb<sup>2+</sup>, Cd<sup>2+</sup>, A1<sup>3+</sup>, and Fe<sup>3+</sup>. even in the presence of high concentrations of The bound Hg<sup>2+</sup> ions can then be stripped from the polymer, allowing the polymer to be reused without significant loss of loading capacity.
Date: December 22, 1998
Creator: Baumann, T F; Fox, G A & Reynolds, J
Partner: UNT Libraries Government Documents Department

Interfacial Reduction-Oxidation Mechanisms Governing Fate and Transport of Contaminants in the Vadose Zone

Description: Immobilization of toxic and radioactive metals in the vadose zone by In Situ Gaseous Reduction (ISGR) using hydrogen sulfide (H2S) is a promising technology for soil remediation. Earlier laboratory and field studies have shown that Cr(VI) can be effectively immobilized by treatment with dilute gaseous H2S. The objective of this project is to characterize the interactions among H2S, the metal contaminants, and soil components. Understanding these interactions is needed to assess the long-term effectiveness of the technology and to optimize the remediation system.
Date: January 11, 2004
Creator: Deng, Baolin; Thornton, Edward; Cantrell, Kirk; Olsen, Khris & Amonette, James
Partner: UNT Libraries Government Documents Department

A REAL TIME COAL CONTENT ORE GRADE (C2OG) SENSOR

Description: This third quarterly technical report discusses the progress made on a machine vision technique for determining coal content and ore grades. The work done this quarter has utilized a miniature imaging spectrometer. Procedures to collect and process the spectral and spatial data from the imaging spectrometer have been established, and software routines have been employed to use this data to differentiate sulfides from background rock in platinum/palladium core samples. These sulfides are indicator minerals for high-grade platinum/palladium ore. Mappings of the sulfides generated with this procedure have been quite accurate. Samples of coal have also been obtained and preliminary measurements with the imaging spectrometer have been made.
Date: April 25, 2002
Creator: Swanson, Dr. Rand
Partner: UNT Libraries Government Documents Department

Calcium/metal Sulfide Battery Development Program. Progress Report, October 1979 - September 1980

Description: A Ca-Al-Si/FeS2 cell has been developed and has exhibited reasonably stable capacity through 3200 h of operation. This system is expected to be capable of meeting the ultimate performance goals (i.e., 160 W.h/kg) of this development program. Further tests of this cell system in the coming year will better define its ultimate performance capabilities.
Date: March 1981
Creator: Barney, Duane L.; Roche, M. F.; Preto, S. K.; Ross, L. E.; Otto, N. C. & Martino, F. J.
Partner: UNT Libraries Government Documents Department

The Chemical Thermodynamic Properties of Hydrocarbons and Related Substances: Properties of 100 Linear Alkane Thiols, Sulfides, and Symmetrical Disulfides in the Ideal Gas State from 0° to 1,000° K

Description: Report describing the chemical thermodynamic properties of 100 linear alkane thiols, sulfides, and symmetrical disulfides in their ideal gas state. Comprehensive tables of basic data are provided.
Date: 1961
Creator: Scott, Donald W. & McCullough, John P.
Partner: UNT Libraries Government Documents Department

Magnetism in BaCoS{sub 2}

Description: BaCoS{sub 2} is a layered Mott-Hubbard insulator that orders antiferromagnetically near 300 K. We report magnetic susceptibility measurements on polycrystalline BaCoS{sub 2} from 77 K to 800 K, and in- and out-of-plane measurements on single crystals from 2 K to 350 K. We also report a powder neutron refinement of the magnetic structure of BaCoS{sub 2}. The neutron measurements indicate that the moments lie in the plane, and that the magnetic unit cell is the same as the (orthorhombic) chemical cell. The ordered moment obtained from the neutron refinement is close to 3 {mu}{sub B} indicating that the Co ions are in the high-spin (S = 3/2) configuration. The effective moment inferred from the high temperature susceptibility, p = 5.26 {mu}{sub B} is also consistent with high-spin Co{sup +2}.
Date: August 1996
Creator: Mandrus, D.; Chakoumakos, B. C.; Fernandez-Baca, J. A.; Nagler, S. E.; Sales, B. C. & Sarrao, J. L.
Partner: UNT Libraries Government Documents Department

HYDROGEN SEPARATION MEMBRANES

Description: A likely membrane for future testing of high-temperature hydrogen separation from a gasification product stream was targeted as an inorganic analog of a dense-metal membrane, where the hydrogen would dissolve into and diffuse through the membrane structure. An amorphous membrane such as zinc sulfide appeared to be promising. Previously, ZnS film coating tests had been performed using an electron-beam vacuum coating instrument, with zinc films successfully applied to glass substrates. The coatings appeared relatively stable in air and in a simple simulated gasification atmosphere at elevated temperature. Because the electron-beam coating instrument suffered irreparable breakdown, several alternative methods were tested in an effort to produce a nitrogen-impermeable, hydrogen-permeable membrane on porous sintered steel substrates. None of the preparation methods proved successful in sealing the porous substrate against nitrogen gas. To provide a nitrogen-impermeable ZnS material to test for hydrogen permeability, two ZnS infrared sample windows were purchased. These relatively thick ''membranes'' did not show measurable permeation of hydrogen, either due to lack of absorption or a negligible permeation rate due to their thickness. To determine if hydrogen was indeed adsorbed, thermogravimetric and differential thermal analyses tests were performed on samples of ZnS powder. A significant uptake of hydrogen gas occurred, corresponding to a maximum of 1 mole H{sub 2} per 1 mole ZnS at a temperature of 175 C. The hydrogen remained in the material at ambient temperature in a hydrogen atmosphere, but approximately 50% would be removed in argon. Reheating in a hydrogen atmosphere resulted in no additional hydrogen uptake. Differential scanning calorimetry indicated that the hydrogen uptake was probably due to the formation of a zinc-sulfur-hydrogen species resulting in the formation of hydrogen sulfide. The zinc sulfide was found to be unstable above approximately 200 C, probably with the reduction to metallic zinc with the evolution of hydrogen ...
Date: August 1, 1999
Creator: McCollor, Donald P. & Kay, John P.
Partner: UNT Libraries Government Documents Department

Crystalline-as-deposited CaGa{sub 2}S{sub 4}:Ce via low-temperature metal-organic chemical vapor deposition

Description: A metal-organic chemical vapor deposition (MOCVD) process for the growth of crystalline-as-deposited cerium doped calcium thiogallate (CaGa{sub 2}S{sub 4}:Ce) at substrate temperatures less than 600{degree}C has been developed. Blue-green electroluminescence was observed with a luminance of {approx} 2 cd/m{sup 2} at 40 volts above threshold using 60 Hz drive frequency. Threshold voltages were approximately 200 V.
Date: May 1, 1995
Creator: Smith, D.C.; Samuels, J.A.; Espinoza, B.F.; Apen, E.; Peachey, N.M.; Dye, R.C. et al.
Partner: UNT Libraries Government Documents Department

New technology for sulfide reduction and increased oil recovery. Third quarter progress report

Description: Project work was initiated by Geo-Microbial Technologies, Inc. (GMT), Ochelata, Oklahoma for Contract Number DE-FG01-97EE15659 on June 18, 1997. The purpose of this project is to demonstrate reduction of sulfide contamination, as well as possible improvement of production in oil and gas production systems. This will be accomplished by application of the BioCompetitive Exclusion (BCX) process developed by GMT. A broad spectrum of well types and geographical locations is anticipated. The BCX process is designed to manipulate indigenous reservoir bacteria with the addition of synergistic inorganic chemical formulae. These treatments will stimulate growth of beneficial microbes, while suppressing metabolic activity of sulfate reducing bacteria (SRB), the primary source of harmful sulfide production.
Date: March 20, 1998
Partner: UNT Libraries Government Documents Department

Metal-organic chemical vapor deposition of the blue electro-luminescent cerium-doped calcium thiogallate from a liquid reagent delivery system

Description: Deposition of CaS, Ga{sub 2}S{sub 3}, and CaGa{sub 2}S{sub 4}:Ce has been accomplished by MOCVD using Ca(tmhd){sub 2}, Ga(tmhd){sub 3}, and Ce(tmhd){sub 4}, with bubblers and with a liquid delivery system to control the flows. Samples were primarily characterized using x-ray fluorescence and electroluminescence measurements of the color and brightness. Deposition using the bubblers showed a definitive relationship between the Ga(tmhd){sub 3} bubbler temperature and the Ga XRF counts. The Ca conversion shows a tenuous relationship with the Ca(tmhd){sub 2} bubbler temperature, but the scatter of the data makes determining a correlation impractical. Use of the liquid delivery system is preferred to the bubblers because it delivered a reliable reagent flow without the same problems of degradation of the reagent over time. Analysis shows the CaS deposition is mass transport limited, while the Ga{sub 2}S{sub 3} is limited by the deposition kinetics. However, application of these mechanisms to the CaGa{sub 2}S{sub 4}:Ce deposition system reveals that the CaGa{sub 2}S{sub 4}: Ce is independent of its components. Further, the deposition of CaGa{sub 2}S{sub 4}:Ce is found to be Ca rich under conditions which leads to lew Ga/Ca radios in the deposited film. This indicates that the conversion of Ca from Ca(tmhd){sub 2} was catalyzed by the slight presence of Ga in the form of CaGa{sub 2}S{sub 4}:Ce or Ga{sub 2}S{sub 3} on the surface. The Ca is thought to be deposited as CaS:Ce since there is a shift in the EL color towards green under low Ga/Ca ratios. The Ca conversion is also found to approach values predicted by the CaS deposition mechanism under conditions which lead to high Ga/Ca ratios, implying that excess Ga{sub 2}S{sub 3} is needed for the deposition of CaGa{sub 2}S{sub 4}:Ce without any CaS:Ce inclusions.
Date: December 31, 1995
Creator: Moss, T.S.; Dye, R.C.; Smith, D.C.; Samuels, J.A.; DelaRosa, M.J. & Schaus, C.F.
Partner: UNT Libraries Government Documents Department

A state-space Bayesian framework for estimating biogeochemical transformations using time-lapse geophysical data

Description: We develop a state-space Bayesian framework to combine time-lapse geophysical data with other types of information for quantitative estimation of biogeochemical parameters during bioremediation. We consider characteristics of end-products of biogeochemical transformations as state vectors, which evolve under constraints of local environments through evolution equations, and consider time-lapse geophysical data as available observations, which could be linked to the state vectors through petrophysical models. We estimate the state vectors and their associated unknown parameters over time using Markov chain Monte Carlo sampling methods. To demonstrate the use of the state-space approach, we apply it to complex resistivity data collected during laboratory column biostimulation experiments that were poised to precipitate iron and zinc sulfides during sulfate reduction. We develop a petrophysical model based on sphere-shaped cells to link the sulfide precipitate properties to the time-lapse geophysical attributes and estimate volume fraction of the sulfide precipitates, fraction of the dispersed, sulfide-encrusted cells, mean radius of the aggregated clusters, and permeability over the course of the experiments. Results of the case study suggest that the developed state-space approach permits the use of geophysical datasets for providing quantitative estimates of end-product characteristics and hydrological feedbacks associated with biogeochemical transformations. Although tested here on laboratory column experiment datasets, the developed framework provides the foundation needed for quantitative field-scale estimation of biogeochemical parameters over space and time using direct, but often sparse wellbore data with indirect, but more spatially extensive geophysical datasets.
Date: April 15, 2009
Creator: Chen, J.; Hubbard, S.; Williams, K.; Pride, S.; Li, L.; Steefel, C. et al.
Partner: UNT Libraries Government Documents Department

Method for direct production of carbon disulfide and hydrogen from hydrocarbons and hydrogen sulfide feedstock

Description: A method for converting hydrocarbons and hydrogen sulfide to carbon disulfide and hydrogen is provided comprising contacting the hydrocarbons and hydrogen sulfide to a bi-functional catalyst residing in a controlled atmosphere for a time and at a temperature sufficient to produce carbon disulfide and hydrogen. Also provided is a catalyst for converting carbon sulfides and hydrogen sulfides to gasoline range hydrocarbons comprising a mixture containing a zeolite catalyst and a hydrogenating catalyst.
Date: December 1998
Creator: Miao, Frank Q. & Erekson, Erek James
Partner: UNT Libraries Government Documents Department

Uranium recovery from a low-grade Katanga sulfide concentrate : topical report

Description: A report which describes a variety of methods for processing a low-grade sulfide concentrate from the Congo. This concentrate consists primarily of sulfides of cobalt, nickel, and iron, plus about 10 percent uranium, present principally as uraninite.
Date: 1953
Creator: Bearse, A. E.; Ewing, R. A.; Sclar, C. B. & Pobereskin, M.
Partner: UNT Libraries Government Documents Department

Rate enhancement for catalytic upgrading coal naphthas. Quarterly progress report for period ending, September 1993

Description: The hydrotreatment of naphtha derived from Illinois {number_sign}6 coal has been carried out over unsupported transition metal sulfide catalysts of the second row of the Periodic Table. The catalysts prepared are similar to the catalysts prepared by Pecoraro and Chianelli (1981). The catalysts exhibit a volcano curve for the HDS of dibenzothiophene similar to that observed by Pecoraro and Chianelli (1981). The catalysts also exhibit similar volcano curves for the HDS, HDN and HDO of the total sulfur, nitrogen and oxygen heteroatoms present in coal-derived naphtha. Ruthenium sulfide is the most active catalyst for all three of these processes. The order of reactivity for HDS, HDN and HDO is Ru > Rh > Mo > Pd > Zr > Nb. The kinetics of total sulfur and nitrogen removal from the coal-derived naphtha are quite complex. The conversion versus residence time data do not fit simple zero or first order kinetics. The individual sulfur compounds present in naphtha exhibit considerable interconversion indicating that C-C bond breaking and hydrogenation of aromatic rings are involved during HDS. The individual nitrogen compounds present in naphtha show that anilines are intermediates in the HDN of nitrogen compounds.
Date: December 31, 1993
Creator: Davis, B. H.
Partner: UNT Libraries Government Documents Department

Ion beam synthesis of CdS, ZnS, and PbS compound semiconductor nanocrystals

Description: Sequential ion implantation followed by thermal annealing has been used to form encapsulated CdS, ZnS, and PbS nanocrystals in SiO{sub 2} and Al{sub 2}O{sub 3} matrices. In SiO{sub 2}, nanoparticles are nearly spherical and randomly oriented, and ZnS and PbS nanocrystals exhibit a bimodal size distribution. In Al{sub 2}O{sub 3}, nanoparticles are faceted and coherent with the matrix. Initial photoluminescence (PL) results are presented.
Date: December 1, 1997
Creator: White, C.W.; Budai, J.D. & Meldrum, A.L.
Partner: UNT Libraries Government Documents Department

DEVELOPMENT OF DEWATERING AIDS FOR MINERALS AND COAL FINES

Description: MCT has developed a suite of novel dewatering chemicals (or aids) that are designed to cause a decrease in the capillary pressures of the water trapped in a filter cake by (1) decreasing the surface tension of water, (2) increasing the contact angles of the particles to be dewatered, and (3) causing the particles to coagulate, all at the same time. The decrease in capillary pressure in turn causes an increase in the rate filtration, an increase in throughput, and a decrease in pressure drop requirement for filtration. The reagents are used frequently as blends of different chemicals in order to bring about the changes in all of the process variables noted above. The minerals and coal samples tested in the present work included copper sulfide, lead sulfide, zinc sulfide, kaolin clay, talc, and silica. The laboratory-scale test work included studies of reagent types, drying cycle times, cake thickness, slurry temperature, conditioning intensity and time, solid content, and reagent dosages. To better understand the mechanisms involved, fundamental studies were also conducted. These included the measurements of the contact angles of the particles to be dewatered (which are the measures of particle hydrophobicity) and the surface tensions of the filtrates produced from dewatering tests. The results of the laboratory-scale filtration experiments showed that the use of the novel dewatering aids can reduce the moistures of the filter cake by 30 to 50% over what can be achieved using no dewatering aids. In many cases, such high levels of moisture reductions are sufficient to obviate the needs for thermal drying, which is costly and energy intensive. Furthermore, the use of the novel dewatering aids cause a substantial increase in the kinetics of dewatering, which in turn results in increased throughput. As a result of these technological advantages, the novel dewatering aids have ...
Date: July 1, 2004
Creator: Yoon, Roe-Hoam; Asmatulu, Ramazan; Yildirim, Ismail; Jansen, William; Zhang, Jinmig; Atkinson, Brad et al.
Partner: UNT Libraries Government Documents Department

Removal of H2S and SO2 by CaCO3-Based Sorbents at High Pressure

Description: The theoretical and experimental investigation of the mechanism of SO2 and H2S removal by CaCO3 -based sorbents (limestones and dolomites) in pressurized uidized-bed coal combustors (PFBC) and high pressure gasi#12;ers, respectively, is the main objective of this study. It is planned to carry out reactivity evolution experiments under simulated high pressure conditions or in high pressure thermogravimetric and, if needed, uidized- bed reactor (high pressure) arrangements. The pore structure of fresh, heat-treated, and half-calcined solids (dolomites) will be analyzed using a variety of methods. Our work will focus on limestones and dolomites whose reaction with SO2 or H2S under atmospheric conditions has been studied by us or other research groups in past studies. Several theoret- ical tools will be employed to analyze the obtained experimental data including a variable di#11;usivity shrinking-core model and models for di#11;usion, reaction, and structure evolution in chemically reacting porous solids. During the six months of this reporting period, work was primarily done on the study of the behavior of the sul#12;dation of limestones under sequential calcination conditions in the presence of small amounts of oxygen and the development of a stochastic simulation code for determining the extent of pore volume trapping (formation of inaccessible pore space) in gas-solid reactions accompanied by pore volume reduction such as the sulfation and sul#12;dation of calcined limestones and dolomites. The incentive for carrying out sul#12;dation experiments in the presence of oxygen was provided by the observation that some sul#12;dation experiments that were conducted as oxygen was accidentally leaking into the feed mixture of the reactor showed completely di#11;erent behavior from that obtained in the absence of oxygen. Experiments were carried out in the thermogravimetric analysis system that we developed for studying gas-solid reactions at atmospheric or subambient pressures. The two CaCO3 solids (Greer limestone and Iceland spar) that we ...
Date: February 1, 1998
Creator: Sotirchos, Stratis V.
Partner: UNT Libraries Government Documents Department