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in publisher: "Virginia Polytechnic Institute and State University. Digital Library and Archives."

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Control of pyrite surface chemistry in physical coal cleaning

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.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Heteroatom speciation in coal liquefaction via FTIR coupled with liquid chromatography. Quarterly progress report, October 1-December 31, 1983

The objectives of the research are (1) evaluate the potential of FT-IR for qualitative functional group detection in chromatographic fractions of highly polar materials, (2) develop separation techniques with the aid of FT-IR detection for concentration of oxygen, nitrogen and sulfur functionalities in synfuels, (3) describe and quantify the various heteroatom functionalities in selected solvent refined coal fractions, (4) place speciation techniques on-line with chromatographic separations, (5… more

Date: May 1, 1984

Creator: Taylor, L.T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Low-pressure approach to the formation and study of exciplex systems. [For CDC 7600]

Studies on the formation and properties of new materials for high-energy, gas-phase lasers are described. Attention is directed mainly to systems having bound excited states but unbound ground states. An important class of such excimer/exciplex systems has a van der Waals dimer/oligomer as its ground state. This research attempts to probe the relative rates of electron pumping of excited-state manifolds and the preferentially pumped vibronic states within each manifold. Reactive quenching of em… more

Date: October 1, 1977

Creator: Sanzone, G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Control of pyrite surface chemistry in physical coal cleaning

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.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development of the chemical and electrochemical coal cleaning process

Studies concerning the use of flotation as an alternative method of separating liberated mineral matter from chemical/electrochemical coal cleaning (CECC) treated coal were continued using Elkhorn No. 3 coal. The results obtained using different methods of recovering the clean product after CECC treatment showed trends similar to those observed previously with Pittsburgh No. 8 coal. The use of flotation after CECC treatment of the Elkhorn No. 3 coal was found to be more efficient than wet-scree… more

Date: January 1, 1991

Creator: Basilio, C.I. & Yoon, Roe-Hoan.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Heat transfer in oscillatory flow. Progress report, January 1983-December 1983

Progress is reported in work with a water tunnel facility and wind tunnel facilities used to study heat transfer in oscillatory flow. Work on both facilities include construction and modifications of the facilities themselves, instrumentation and data acquisition, and experimental measurements. A computer code was developed for the calculation of steady and unsteady heat transfer over the attached portion of the boundary layer. The equations of momentum and energy were recast in their finite-di… more

Date: January 1, 1983

Creator: Telionis, D. P. & Diller, T. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development and application of analytical techniques to chemistry of donor solvent liquefaction. Final report, August 31, 1977-December 31, 1979

The scope of this project was to develop and apply analytical techniques for the characterization of coal conversion products. Solvent-refined coal served as the coal-derived material for the duration of the study. The investigation has focused primarily in the areas of separations and nuclear magnetic resonance spectroscopy. Highlights of the twenty-eight month study are listed and followed by a brief synopsis of the major findings.

Date: January 1, 1979

Creator: Squires, A. M.; Dorn, H. C.; Taylor, L. T.; Dillard, J. G. & Rony, P. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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CdSiAs/sub 2/ thin films for solar cell applications. Second quarter report, July 1, 1979-September 30, 1979. [CdSiAs/sub 2//CdS]

Sputtered films have been formed with two improved composite (Si + CdAs/sub 2/) targets. Near stoichiometric and mechanically continuous CdSiAs/sub 2/ films have been formed on metal substrates. Films of this type will be used over the next reporting period for heterojunction formation. Evaporation studies related to CdAs/sub 2/ have been completed. Stoichiometric CdAs/sub 2/ films could not be formed by means of single-source evaporation of CdAs/sub 2/ bulk. Hence, this dual source approach (S… more

Date: October 1, 1979

Creator: Burton, L.C. & Slack, L.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Control of pyrite surface chemistry in physical coal cleaning

One of the most difficult separations in minerals processing involves the differential flotation of pyrite and coal. Under practical flotation conditions, they are both hydrophobic and no cost-effective method has been developed to efficiently reject the pyrite. The problem arises from inherent floatability of coal and pyrite. Coal is naturally hydrophobic and remains so under practical flotation. Although pyrite is believed to be naturally hydrophilic under practical flotation conditions it un… more

Date: June 24, 1992

Creator: Yoon, R. H. & Richardson, P. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Low-pressure appraoch to the formation and study of exciplex systems. [VPI and SU, Blacksburg, Virginia]

Date: November 1, 1977

Creator: Sanzone, G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Control of pyrite surface chemistry in physical coal cleaning

To better understand the flotation behavior of coal pyrite, studies have been initiated to characterize the floatability of coal pyrite and mineral pyrite. The hydrophobicity of coal material pyrite was examined over a range of pH and oxidation times. The results indicate that surface oxidation plays an important role in coal and mineral pyrite hydrophobicity. The hydrophobicity of mineral pyrite decreases with increasing oxidation time (20 min. to 5 hr.) and increasing pH (pH 4.6 to 9.2), with… more

Date: January 17, 1990

Creator: Luttrell, G. H.; Yoon, R. H.; Zachwieja, J. & Lagno, M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

CdSiAs/sub 2/ thin films for solar cell applications. First quarter report April 9, 1979-June 30, 1979

Near stoichiometric bulk polycrystalline CdSiAs/sub 2/ has been synthesized by two techniques: (1) direct fusion of the elements and (2) direct fusion of the binaries SiAs, Cd/sub 3/As/sub 2/ and CdAs/sub 2/. The latter technique resulted in denser ternary material with good homogeneity. The above binaries melt congruently and were also formed by direct fusion. Sputtered ternary films were formed using a bulk CdSiAs/sub 2/ target, and a composite target of CdAs/sub 2/ discs in a Si plate. Compo… more

Date: July 25, 1979

Creator: Burton, L.C. & Slack, L.H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development of the chemical and electrochemical coal cleaning process

The objectives of this effort are (a) to learn the mechanisms by which the Chemical and Electrochemical Coal Cleaning (CECC) process removes pyritic sulfur and ash from coal, (b) to learn more about the operating parameters of the process, (c) to collect engineering information for scale-up of the process, and (d) to test the CECC process on a bench-scale continuous operation.

Date: January 1, 1988

Creator: Yoon, R. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development of the chemical and electrochemical coal cleaning process

Liberation studies on the Elkhorn No. 3 coal were completed in this quarter. The results obtained from the 65 {times} 150 mesh samples showed that the amount of mineral matter and pyrite liberated by the Chemical and Electrochemical Coal Cleaning (CECC) process increases with time. The free mineral matter undergoes some reduction in size during the CECC treatment and the majority of the liberated mineral particles in this sample are finer than 150 mesh. This is opposite that found for the Pitts… more

Date: January 1, 1991

Creator: Basilio, C.I. & Yoon, Roe-Hoan.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Performance of a diesel engine operating on raw coal-diesel fuel and solvent refined coal-diesel fuel slurries. Final report

Performance tests using an 11 kW single cylinder diesel engine were made to determine the effects of three different micronized coal-fuel oil slurries being considered as alternative fuels. Slurries containing 20, 32, and 40%-wt micronized raw coal in No. 2 fuel oil were used. Results are presented indicating the changes in the concentrations of SO/sub X/ and NO/sub X/ in the exhaust, exhaust opacity, power and efficiency, and in wear rates relative to operation on fuel oil No. 2. The engine wa… more

Date: March 1, 1980

Creator: Marshall, H. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Holifield Heavy Ion Research Facility

The Holifield Heavy Ion Research Facility has been in routine operation since July 1982. Beams have been provided using both the tandem accelerator alone and a coupled mode in which the Oak Ridge Isochronous Cyclotron is used as an energy booster for tandem beams. The coupled mode has proved to be especially effective and has allowed us to provide a wide range of energetic beams for scheduled experiments. In this report we discuss our operational experience and recent development activities.

Date: January 1, 1985

Creator: Jones, C. M.; Alton, G. D.; Ball, J. B.; Biggerstaff, J. A.; Dowling, D. T.; Erb, K. A. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Development of the chemical and electrochemical coal cleaning process

The continuous testing of the Chemical and Electrochemical Coal Cleaning (CECC) bench-scale unit (Task 6) was completed successfully in this quarter using Middle Wyodak and Elkhorn No. 3 coal samples. The CECC unit was run under the optimum conditions established for these coal samples in Task 4. For the Middle Wyodak coal, the ash content was reduced from 6.96% to as low 1.61%, corresponding to an ash rejection (by weight) of about 83%. The ash and sulfur contents of the Elkhorn No. 3 coal wer… more

Date: January 1, 1991

Creator: Basilio, C.I. & Yoon, Roe-Hoan.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

In-Plant Testing of High-Efficiency Hydraulic Separators, Phase II Annual Technical Progress Report: 2005

Hydraulic separators are commonly used for particle size classification and gravity concentration of minerals and coal. Unfortunately, the efficiency of these processes can be quite low due to poor equipment design and variations in feed consistency. To help alleviate these problems, an industry-driven R&D program has been undertaken to develop a new generation of hydraulic separators that are more efficient and less costly to operate and maintain. These units, which are commercially called… more

Date: May 22, 2006

Creator: Luttrell, G. H.; Honaker, R. Q.; Bratton, R. C.; Westerfield, T. C. & Kohmuench, J. N.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Optical Fiber Sensor Instrumentation for Slagging Coal Gasifiers

Coal gasifier is one of the most promising solutions for clean fossil energy. Refractory thickness monitoring and online real-time temperature measurement is needed for improved reliability and advanced process control for current and future generation power plants. The objective of this program is to design and implement an optical fiber based sensing system that could potentially be used to monitor refractory wall thickness and temperature inside a coal gasifier. For the thickness monitoring,… more

Date: July 19, 2008

Creator: Wang, Anbo & Cooper, Kristie

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Digital Manufacturing of Gradient Meshed SOFC Sealing Composites with Self-Healing Capabilities

Solid oxide fuel cells (SOFC) hold great promise for clean power generation. However, high temperature stability and long term durability of the SOFC components have presented serious problems in SOFC technological advancement and commercialization. The seals of the fuel cells are the most challenging area to address. A high temperature gas seal is highly needed which is durable against cracking and gas leakage during thermal cycling and extended operation. This project investigates a novel com… more

Date: December 21, 2007

Creator: Lu, Kathy; Story, Christopher & Reynolds, W.T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Properties of e/sup +/e/sup -/ interactions at. sqrt. s = 50 and 52 GeV

Bhabha scattering and multi-hadronic e/sup +/e/sup -/ annihilation events have been observed in the AMY detector at ..sqrt..s = 50 GeV and ..sqrt..s = 52 GeV at the TRISTAN e/sup +/e/sup -/ storage ring. Here we report the results of a preliminary analysis of the properties of these events. We present results for the e/sup +/e/sup -/ ..-->.. e/sup +/e/sup -/, e/sup +/e/sup -/ ..-->.. ..gamma gamma.. and e/sup +/e/sup -/ ..-->.. ..mu../sup +/..mu../sup -/ differential cross sections as well as f… more

Date: July 1, 1987

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Control of pyrite surface chemistry in physical coal cleaning

Several pyrite depressants have been evaluated for their effectiveness in depressing coal pyrite. A novel reagent, NVT, has been synthesized and shown to be selective for the separation of coal from coal pyrite by froth flotation. This organic reagent contains no sulfur group in its structure and exhibits a stronger affinity toward pyrite than toward coal. The effects of a number of parameters such as pH, reagent concentration and flotation time on flotation response were investigated in a micr… more

Date: January 1, 1990

Creator: Luttrell, G. H.; Yoon, R. H.; Zachwieja, J. B. & Lagno, M. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Research and development entitled smart structures for fossil energy applications

Two different fiber optic sensors were considered for use in ceramic cross flow filters. The intensity-based sensor was tested with a great degree of success. Even with a computerized data acquisition system, the intensity-based sensor was unable to achieve the resolution of the Fabry-Perot sensor. Another drawback of the intensity sensor is the hysteresis behavior observed over cyclic variation of temperature. We have determined that extrinsic Fabry-Perot fiber optic sensors can be used to mea… more

Date: December 1, 1990

Creator: Claus, R.O.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Performance of a diesel engine; operating on raw coal-diesel engine; solvent refined coal-diesel fuel slurries. Quarterly report

It has been difficult to obtain stable experimental slurries of coal or solvent-refined coal for testing in diesel engines. Attempts to burn the 40 percent by weight raw coal-fuel oil slurry were hampered from the outset. First the transfer pump would not deliver the slurry to the injection pump. This problem was overcome by raising the slurry storage tank to increase the positive head on the pump inlet. With the engine running on the slurry blow-by of gases into the crank case increased consid… more

Date: December 1, 1979

Creator: Marshall, H. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department