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Control of pyrite surface chemistry in physical coal cleaning

Description: The successful separation of pyrite from coal by flotation is dependent to a large extent upon the selectivity of the process, and the use of a pyrite depressant is one of the most important and cost-effective techniques for achieving this. This report evaluates the effects of three factors on the floatability of pyrite. These are (1) the superficial oxidation of pyrite, (2) the contamination of pyrite surfaces by carbonaceous matter, and (3) pulp redox potentials. XPS (x-ray photoelectron spec… more
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H. & Ou, Z. S.
Partner: UNT Libraries Government Documents Department
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Molecular ingredients of heterogeneous catalysis

Description: The purpose of this paper is to present a review and status report to those in theoretical chemistry of the rapidly developing surface science of heterogeneous catalysis. The art of catalysis is developing into science. This profound change provides one with opportunities not only to understand the molecular ingredients of important catalytic systems but also to develop new and improved catalyst. The participation of theorists to find answers to important questions is sorely needed for the soun… more
Date: June 1, 1982
Creator: Somorjai, G.A.
Partner: UNT Libraries Government Documents Department
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Low-Btu coal-gasification-process design report for Combustion Engineering/Gulf States Utilities coal-gasification demonstration plant. [Natural gas or No. 2 fuel oil to natural gas or No. 2 fuel oil or low Btu gas]

Description: This report describes a coal gasification demonstration plant that was designed to retrofit an existing steam boiler. The design uses Combustion Engineering's air blown, atmospheric pressure, entrained flow coal gasification process to produce low-Btu gas and steam for Gulf States Utilities Nelson No. 3 boiler which is rated at a nominal 150 MW of electrical power. Following the retrofit, the boiler, originally designed to fire natural gas or No. 2 oil, will be able to achieve full load po… more
Date: June 1, 1982
Creator: Andrus, H E; Rebula, E; Thibeault, P R & Koucky, R W
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.)
Partner: UNT Libraries Government Documents Department
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Degradation of cellulosic biomass and its subsequent utilization for the production of chemical feedstocks. Progress report, March 1, 1977--May 31, 1977

Description: The degradation of cellulosic biomass continues to focus on the anaerobic thermophile Clostridium thermocellum. When grown on crystalline cellulose (MN300) in batch culture, there is an initial rapid accumulation of reducing sugars but the sugars are rapidly metabolized in later times during the fermentation. When grown on Solka floc with periodic addition of the substrate, there is a continual accumulation of reducing sugars (xylose, glucose, and cellobiose) as well as ethanol and acetic acid … more
Date: June 1, 1977
Creator: Wang, D. I. C.; Cooney, C. L.; Demain, A. L.; Gomez, R. F. & Sinskey, A. J.
Partner: UNT Libraries Government Documents Department
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A Theoretical Study of the Transient Operation and Stability of Two-Phase Natural Circulation Loops

Description: Mathematical models of the time-dependent behavior of two-phase natural- circulation loops were used to predict the operation and to explain the unusual instability sometimes observed. The initial results obtained for a loop similar to the Univ. of Minnesota loop were used to formulate a more complex and accurate model, and the predicted transient behavior was in close agreement with the experimental results from the Minnesota loop. For a 300psia, high-pressure loop, unstable oscillatory behavi… more
Date: June 1, 1961
Creator: Garlid, K.; Amundson, N. R. & Isbin, H. S.
Partner: UNT Libraries Government Documents Department
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Molecular biological enhancement of coal biodesulfurization. [Rhodococcus, thiobacillus]

Description: The objective of this project is to produce one or more microorganisms capable of removing the organic and inorganic sulfur in coal. The original specific technical objectives of the project were to: clone and characterize the genes encoding the enzymes of the 4S'' pathway (sulfoxide/sulfone/sulfonate/sulfate) for release of organic sulfur from coal; return multiple copies of genes to the original host to enhance the biodesulfurization activity of that organism; transfer this pathway into a fas… more
Date: June 14, 1990
Creator: Litchfield, J. H.; Fry, I.; Wyza, R. E.; Palmer, D. T.; Zupancic, T. J. & Conkle, H. N.
Partner: UNT Libraries Government Documents Department
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Chemistry research and development. Progress report, December 1978-May 1979. [Component, pilot plant, instrumentation]

Description: Progress and activities are reported on component development, pilot plant development, and instrumentation and statistical systems. Specific items studied include processing of pond sludge, transport of radioactive materials and wastes, corrosion, decontamination and cleaning, fluidized-bed incineration, Pu contamination of soils, chemical analysis, radiometric analysis, security. (DLC)
Date: June 30, 1980
Creator: Miner, F. J.
Partner: UNT Libraries Government Documents Department
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Study of the corrosion rate behavior of ion implanted Fe-based alloys

Description: We report on some studies we have made of the time evolution of the corrosion behavior of ion implanted samples of pure iron, medium carbon steel, and 18-8 Cr-Ni stainless steel. Ti, Cr, Ni, Cu, Mo and Yb were implanted at mean ion energies near 100 keV and at doses up to 1 {times} 10{sup 17} cm{sup {minus}2} using a Mevva metal ion implantation facility. A novel feature of this experiment was the simultaneous implantation with several different implanted species. The implanted samples were imm… more
Date: June 1, 1991
Creator: Weiping, Cai; Wei, Tian; Wu Run (Wuhan Iron and Steel Univ., HB (China)); Godechot, X. & Brown, I. (Lawrence Berkeley Lab., CA (United States))
Partner: UNT Libraries Government Documents Department
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Control of pyrite surface chemistry in physical coal cleaning

Description: To better understand the surface chemical properties of coal and mineral pyrite, studies on the effect of flotation surfactants (frother and kerosene) on the degree of hydrophobicity have been conducted. The presence of either frother or kerosene enhanced the flotability of coal and mineral pyrite with a corresponding decrease in induction time over the pH range examined. Scanning electron microscopy (SEM) results indicate a correlation exists between the sample surface morphology and crystal s… more
Date: June 24, 1992
Creator: Luttrell, G. H.; Yoon, R. H.; Zachwieja, J. & Lagno, M.
Partner: UNT Libraries Government Documents Department
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HC quench layer formation in combustion processes. Technical progress report, January-April 1980

Description: The project is aimed at understanding wall quenching and other processes responsible for surface generated hydrocarbons in combustion under engine-like conditions. The study concerns the effects of turbulence on the evolution of hydrocarbons. At the conclusion of the program, significant new experimental information will have been generated and an analytical model of the fluid mechanics and some aspects of the chemistry of quenching will be formulated. The work is divided into three tasks: (1) … more
Date: June 1, 1980
Creator: Lavoie, G. A.
Partner: UNT Libraries Government Documents Department
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Biological production of organic solvents from cellulosic wastes. Progress report, September 15, 1976--September 14, 1977

Description: The objectives of this project are to optimize a modular process to convert cellulosic wastes to butanol and other oil-sparing chemicals. Research to date has focused on developing analytical methods, establishing a good data base and improving cellulase yields. Reliable assay methods for the Thermoactinomyces cellulase complex have been developed, measuring glucose and reducing sugar from filter paper and Avicel for total cellulase activity, viscosity change with carboxymethyl cellulose for th… more
Date: June 1, 1977
Creator: Pye, E.K.; Humphrey, A.E. & Forro, J.R.
Partner: UNT Libraries Government Documents Department
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Research into the pyrolysis of pure cellulose, lignin, and birch wood flour in the China Lake entrained-flow reactor

Description: This experimental program used the China Lake entrained-flow pyrolysis reactor to briefly investigate the pyrolysis of pure cellulose, pure lignin, and birch wood flour. The study determined that the cellulose and wood flour do pyrolyze to produce primarily gaseous products containing significant amounts of ethylene and other useful hydrocarbons. During attempts to pyrolyze powdered lignin, the material melted and bubbled to block the reactor entrance. The pure cellulose and wood flour produced… more
Date: June 1, 1980
Creator: Diebold, J.
Partner: UNT Libraries Government Documents Department
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Comet Halley, parameter study I

Description: To aid in defining a mission to comet P/Halley, its inner coma is simulated by a computer program that models time-dependent chemical reactions in a radially and isentropically expanding gas, taking into account attenuation of solar ultraviolet radiation in the subsolar direction. Column density predictions are based on intelligently selected combinations of poorly known values for nucleus parameters that include size, visual albedo, and infrared emissivity. Only one chemical composition and a … more
Date: June 1, 1982
Creator: Huebner, W.F. & Fikani, M.M.
Partner: UNT Libraries Government Documents Department
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LIMB Demonstration Project Extension

Description: The basic goal of the Limestone Injection Multistage Burner (LIMB) demonstration is to extend LIMB technology development to a full- scale application on a representative wall-fired utility boiler. The successful retrofit of LIMB to an existing boiler is expected to demonstrate that (a) reductions of 50 percent or greater in SO{sub x} and NO{sub x} emissions can be achieved at a fraction of the cost of add-on FGD systems, (b) boiler reliability, operability, and steam production can be maintain… more
Date: June 15, 1989
Partner: UNT Libraries Government Documents Department
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CHEMICAL ENGINEERING DIVISION SUMMARY REPORT, JANUARY-MARCH 1962

Description: Additional experiments conducted on nitridation of irradiated U-fissium fuel pins revealed that irradiation does not greatly affect the nitridation rate at 300 deg C. In skullreclamation development, a phase separation common to both the blanket- and skull-processes was investigated in which a 50% Mg-- Zn supernatant solution was removed from precipitated U metal. In most runs the supernatant phase was removed with negligible U entrainment. The reduction rate of ZrO by Zn--Mg solution under sku… more
Date: June 1, 1962
Partner: UNT Libraries Government Documents Department
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Effect of sulfuric acid, oxygen, and hydrogen in high-temperature water on stress corrosion cracking of sensitized Type 304 stainless steel

Description: The influence of dissolved oxygen and hydrogen and dilute sulfuric acid in 289/sup 0/C water on the stress-corrosion-cracking susceptibility of lightly and moderately sensitized Type 304 stainless steel was determined in constant-extension-rate tensile (CERT) tests. The CERT parameters and the fracture surface morphologies were correlated with the concentrations of dissolved oxygen and sulfate, and the electrochemical potentials of platinum and Type 304 stainless steel electrodes in simulated b… more
Date: June 1, 1983
Creator: Ruther, W.E.; Soppet, W.K.; Ayrault, G. & Kassner, T.F.
Partner: UNT Libraries Government Documents Department
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Pilot plant studies of the bioconversion of cellulose and production of ethanol

Description: Progress is reported in the following studies on analysis and evaluation of potential raw materials: preliminary pretreatment studies using wheat straw; extraction of wheat straw with alcohol and water at elevated temperatures; extraction of ground wood with alcohol and water at elevated temperatures; and, delignification of newsprint with ethylene glycol. Other research in progress includes studies on: utilization of hemicellulose sugars; process design and economics of hydrolysis processes an… more
Date: June 30, 1977
Creator: Wilke, C.R.
Partner: UNT Libraries Government Documents Department
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Process feasibility study in support of silicon material Task I. Quarterly technical progress report (XIX), March 1-May 31, 1980

Description: Analyses of process system properties were continued for chemical materials important in the production of silicon. Major physical, thermodynamic and transport property data are reported for silicon including critical constants, vapor pressure, heat of vaporization, heat of sublimation, heat capacity, density, surface tension, viscosity and thermal conductivity. The property data covers both liquid and solid phases and are reported as a function of temperature for rapid engineering usage. Major… more
Date: June 1, 1980
Creator: Yaws, C.L. & Li, K.Y.
Partner: UNT Libraries Government Documents Department
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Bates solar industrial process steam application environmental impact assessment

Description: It is planned to install 34,440 square feet of linear parabolic trough solar collectors at a new corrugator plant for making corrugated boxes. The system is to operate in parallel with a fossil fuel boiler. An assessment is presented of the impacts of the solar energy system on the existing environment and to determine whether or not a more detailed environmental impact statement is needed. The environmental assessment is based on actual operational data obtained on the collector, fluid, and he… more
Date: June 30, 1981
Partner: UNT Libraries Government Documents Department
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Recent coal-oil mixture combustion tests at PETC

Description: Coal-oil mixture combustion tests with coal concentrations of up to 50 percent were successfully conducted in a 700 horsepower watertube boiler designed originally for oil firing. A 500-h duration test with coal-oil mixture containing 40 percent coal has also been completed. No derating of the boiler occurred, carbon-conversion efficiencies were above 98 percent, and boiler efficiencies were the same as when firing No. 6 fuel oil. All combustion tests were conducted with No. 6 fuel oil mixed wi… more
Date: June 1, 1980
Creator: Pan, Y. S.; Bellas, G. T.; Mathur, M. P.; Joubert, J. I. & Bienstock, D.
Partner: UNT Libraries Government Documents Department
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Direct chlorination process for geothermal power plant off-gas - hydrogen sulfide abatement

Description: The Direct Chlorination Process removes hydrogen sulfide from geothermal off-gases by reacting hydrogen sulfide with chlorine in the gas phase. Hydrogen chloride and elemental sulfur are formed by this reaction. The Direct Chlorination Process has been successfully demonstrated by an on-site operation of a pilot plant at the 3 M We HPG-A geothermal power plant in the Puna District on the island of Hawaii. Over 99.5 percent hydrogen sulfide removal was achieved in a single reaction stage. Chlori… more
Date: June 1, 1983
Creator: Sims, A.V.
Partner: UNT Libraries Government Documents Department
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