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(Studies of supported hydrodesulfurization catalysis)

Description: Research progress to be reviewed here will be in three areas. First, correlation of the distribution of molybdenum oxidation states in reduced Mo/Al{sub 2}O{sub 3} catalysts with benzene hydrogenation activity. Second, the use of factor analysis curve-fitting to determine the distribution of molybdenum oxidation states in reduced Mo/TiO{sub 2} catalysts. Third, quantitative Raman and ESCA characterization of W/TiO{sub 2} catalysts.
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department

Treatment of metal-laden hazardous wastes with advanced clean coal technology by-products. Quarterly report, September 1995--December 1995

Description: This fifth quarterly report describes work done during the fifth three-month period of the University of Pittsburgh`s project on the {open_quotes}Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.{close_quotes} Participating with the university on this project is Mill Service, Inc. This report describes the activities of the project team during the reporting period. The principal work has focussed upon completing laboratory evaluation of samples produced during Phase 1, preparing reports and presentations, and seeking environmental approvals and variances to permits that will allow the field work to proceed. The compressive strength of prepared concretes is described.
Date: March 1, 1996
Partner: UNT Libraries Government Documents Department

A rheometer for measuring the material moduli for granular solids. Quarterly progress report, March 1, 1991--May 31, 1991

Description: In this quarterly report, we discuss the progress that has been made with regard to our research on an experimental method for characterizing the material properties of granular solids. In the previous report we have discussed the various aspects of selecting a particular component for the instrument we have proposed to build. Keeping these various aspects in mind, we have selected and ordered these components. Some of the parts are being fabricated in the workshop while others have been ordered. While some of the orders have been delivered others are yet to come. We are in the process of putting the equipment together. However, since the load-cells and some other crucial parts have not been delivered, this will have to wait.
Date: February 1, 1996
Creator: Rajagopal, K.R.
Partner: UNT Libraries Government Documents Department

Treatment of metal-laden hazardous wastes with advanced clean coal technology by-products. Quartery report, August 1994--November 1994

Description: This first quarterly report describes work during the first three months of the University of Pittsburgh`s (Pitt`s) project on the {open_quotes}Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.{close_quotes} Participating with Pitt on this project are Dravo Lime Company (DLC), Mill Service, Inc. (MSO and the Center for Hazardous Materials Research (CHMR)). The report states the goals of the project - both general and specific - and then describes the activities of the project team during the reporting period. All of this work has been organizational and developmental in nature. No data has yet been collected. Technical details and data will appear for the first time in the second quarterly report and be the major topic of subsequent reports.
Date: December 1, 1994
Partner: UNT Libraries Government Documents Department

Treatment of metal-laden hazardous wastes with advanced clean coal technology by-products. Quarterly report, February--May 1995

Description: This report describes the activities of the project team during the reporting period. The principal work has focused upon the laboratory treatment of six wastes with three by-products and the evaluation of the stability of the resulting eighteen materials. Other efforts during the third quarter have been directed toward completion of the collection and analysis of by-products, the identification of a suitable fourth by-product, and the definition of the approach to the solidification tests. The activity on the project during the third quarter of Phase One has fallen into three major areas: acquiring and analyzing by-products; treating hazardous wastes with by-products in the laboratory and analyzing the results; and conducting administrative activities, including public relations and personnel additions. The hazardous wastes that are used include industrial wastewater treatment residue from battery manufacturing plant; contaminated soil from a remediation project conducted at a munitions depot; contaminated soil from a remediation project conducted at an abandoned industrial site; contaminated soil from a remediation project conducted at a former sewage treatment plant; air pollution control dust from basic oxygen furnace steel production; and air pollution control ash from municipal waste incineration.
Date: July 1, 1995
Partner: UNT Libraries Government Documents Department

A study of multistage/multifunction column for fine particle separation

Description: The overall objective of the research program is to explore the potential application of a new invention involving a multistage column equipped with vortex-inducing loop-flow contactors (hereafter referred to as the multistage column) for fine coal cleaning process. The research work will identify the design parameters and their effects on the performance of the separation process. The results of this study will provide an engineering basis for further development of this technology in coal cleaning and in the general areas of fluid/particle separation. In the last quarter, we investigated the fine coal beneficiation behaviors in the multistage column and the conventional column. In this quarter, we have initiated the wastewater treatment tests program to verify the multifunction features of the multistage column. We also performed data analysis of the bubble sizes using a model based on the unified proportionality equation. 7 refs., 10 figs., 7 tabs.
Date: July 1, 1996
Creator: Chiang, Shiao-Hung
Partner: UNT Libraries Government Documents Department

Stabilization of DOE hazardous wastes with clean-coal technology by-products

Description: The objective of this research is to evaluate both the long term and short term stabilization of DOE metal-containing hazardous wastes with clean coal technology (CCT) by-products. This work builds directly on a currently funded DOE/METC project with the University of Pittsburgh (prime contractor) in conjunction with Mill Service (a centralized waste treater), and Dravo Lime Corporation. Studies fall into two categories: (1) observation of the ability of CCT to stabilize and solidify characteristic toxic/hazardous metal-laden wastes (and other DOE metal containing wastes) over the near term via conversion of such wastes into a non-hazardous form by means of pozzolanic type reactions with by-products, and; (2) characterization and understanding of the longer term environmental and physical stability of the resultant solidified matrix in terms of potentially time dependent physical and chemical/toxicological leaching characteristics taking place due to slow solid phase crystalline reactions.
Date: December 31, 1996
Creator: Neufeld, R.D. & Cobb, J.T.
Partner: UNT Libraries Government Documents Department

Treatment of metal-laden hazardous wastes with advanced clean coal technology by-products. Quarterly report, November 1994--February 1995

Description: This second quarterly report describes work during the second three months of the University of Pittsburgh`s (Pitt`s) project on the {open_quotes}Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.{close_quotes} Participating with Pitt on this project are Dravo Lime Company (DLC), Mill Service, Inc. (MSI) and the Center for Hazardous Materials Research (CHMR). The report describes the activities of the project team during the reporting period. The principal work has focussed upon the acquisition of by-product samples and their initial analysis. Other efforts during the second quarter have been directed toward identifying the first hazardous waste samples and preparing for their treatment and analysis. Relatively little data has yet been collected. Major presentation of technical details and data will appear for the first time in the third quarterly report. The activity on the project during the second quarter of Phase One, as presented in the following sections, has fallen into seven areas: (1) Acquiring by-products, (2) Analyzing by-products, (3) Identifying, analyzing and treating suitable hazardous wastes, (4) Carrying out the quality assurance/quality control program, (5) Developing background, and (6) Initiating public relations
Date: March 1, 1995
Partner: UNT Libraries Government Documents Department

Treatment of metal-laden hazardous wastes with advanced clean coal technology by-products. Quarterly report, May 1995--August 1995

Description: This fourth quarterly report describes work done during the fourth three-month period of the University of Pittsburgh`s project on the {open_quotes}Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.{close_quote} Participating with the university on this project are Dravo Lime Company, Mill Service, Inc., and the Center for Hazardous Materials Research. This report describes the activities of the project team during the reporting period. The principal work has focussed upon the production of six sets of samples with high water content for solidification testing and the mixing of five dry samples for solidification testing by the Proctor method. Twenty-eight day compressive strengths are reported for five of the six sets of samples with high water content. The report also discusses completion of the format of the database and the inclusion in it of all data collected to date. Special reports presented during the quarter include the Continuation Application, a News Release, and modification to the Test Plan. Work is progressing on the NEPA report and the Topical Report. The activity on the project during the fourth quarter of Phase one, as presented in the following sections, has fallen into six major areas: (1) Completion of by-product evaluations, (2) Completion of analyses of six wastes, (3) Initiation of eleven solidification tests, (4) Continued extraction and extract analysis of solidified samples, (5) Development of the database, and (6) Production of reports.
Date: November 1, 1995
Partner: UNT Libraries Government Documents Department

A rheometer for measuring the material moduli for granular solids. Final report, August 7, 1990--February 6, 1995

Description: A great many industrial processes involve interaction between solids and fluids (i.e. gases or liquids). Combustion, gasification of solid fuels, shales or solid wastes, drying of particles, calcining, particle heating, regenerative heat exchangers, oxidation or reduction of ores, metal surface treatments and catalytic and thermal cracking are some of such processes. Solids and fluids serve different roles and several combinations of solids and fluids can arise in a practical situation. Thus, when considering processes or plants it is necessary to be clear as to the particular purpose served by the fluids and the solids. Heating and drying of solids, for example, involve heat and mass transfer only, whereas combustors, gasifiers etc. have the additional complication of chemical reactions which have to be carried out simultaneously with heat and mass transfer. Again, there are many processes where just the flow of granular particles take place, for example, the flow of food grain, coal or sand particles through bin, silo, hoppers, chutes, conveyor belts, inclined planes etc. In most of these cases, a theoretical modeling of the process requires a complete and thorough understanding of the phenomena involved and constitutive modeling of the constituents along with the usual balance laws. In a process, where both a fluid and a solid constituents are involved, it is essential to model both the constituents such that the models accurately describes the characteristics of the constituent concerned. While there are many different models available for fluids, the models for granular materials lack from an understanding of the material parameters.
Date: March 1, 1998
Creator: Rajagopal, K.R.
Partner: UNT Libraries Government Documents Department

Measurement of time dependent B{sub d}{sup 0} {bar B}{sub d}{sup 0} mixing parameter using opposite side lepton and D* meson in p{bar p} collisions at {radical}s = 1.8 TeV

Description: This thesis presents the results from the investigation of time dependent B{sub d}{sup 0} {bar B}{sub d}{sup 0} mixing in B {yields} lepton X, B{sub d}{sup 0} {yields} D*{sup -} {yields} {bar D}{sup 0} {pi}{sup -}, {bar D}{sup 0} {yields} K{sup +} {pi}{sup -} channel in p{bar p} collisions at {radical}s = 1.8 TeV using 110 pb{sup -1} data collected with the CDF detector at the Fermilab Tevatron Collider. The {bar D}{sup 0} vertex is reconstructed. The B{sub d}{sup 0} decay length is estimated using the distance from the primary vertex to the measured position of the D{sup 0} vertex. The B{sup 0} momentum is estimated using the D{sup 0} momentum and a kinematic correction factor from Monte Carlo. With the dilution floating, {Delta}M{sub d} = 0.55 {+-}{sub 0.16}{sup 0.15} (stat) {+-} 0.06 (syst)ps{sup -1} is measured.
Date: January 13, 1998
Creator: Vandenbrink, S.C.
Partner: UNT Libraries Government Documents Department

A rheometer for measuring the material moduli for granular solids. Quarterly progress report, September 1, 1990--November 30, 1990

Description: In this quarterly report, we discuss the progress that has been made with regard to our research on an experimental method for characterizing the material properties of granular solids. We have proposed to build an orthogonal rheometer which consists of two disks rotating with the same angular speed about distinct axes. By measuring the forces and the torque acting on the top and bottom disks and correlating them with the theoretical expressions for the tractions and moment, we can characterize the properties of the material that is placed between the disks. The above described technique draws upon a method devised for measuring the properties of viscoelastic solids and fluids.
Date: February 1, 1996
Creator: Rajagopal, K.R.
Partner: UNT Libraries Government Documents Department

A rheometer for measuring the material moduli for granular solids. Quarterly progress report, December 1, 1990--Februray 28, 1991

Description: In this report, we will outline an experimental method for characterizing the material properties of granular solids, like coal particles, and other powders and slurries. The instrument to be used for this purpose consists of two disks rotating with the same angular speed about distinct axes. By measuring the forces and the torque acting on the top and bottom disks and correlating them with the theoretical expressions for the tractions and moment in question. The above described technique draws upon a method devised for measuring the properties of viscoelastic solids and fluids.
Date: February 1, 1996
Creator: Rajagopal, K.R.
Partner: UNT Libraries Government Documents Department

A rheometer for measuring the material moduli for granular solids. Quarterly progress report, March 1, 1993--May 31, 1993

Description: This report describes the design of an orthogonal rheometer for the measuring of properties of granular materials such as coal. A section is presented on constitutive modeling of granular materials based on continuum theory.
Date: February 1, 1996
Creator: Rajagopal, K.R.
Partner: UNT Libraries Government Documents Department

(The relationship between microstructure and magnetic properties in high-energy permanent magnets characterized by polytwinned structures)

Description: This report summarizes the results of a study of the relationship between microstructure and magnetic properties in a unique genre of ferromagnetic material characterized by a polysynthetically twinned structure which arises during solid state transformation. These results stem from the work over a period of approximately 27 months of a nominal 3 year grant period. The report also contains a proposal to extend the research project for an additional 3 years. The polytwinned structures produce an inhomogeneous magnetic medium in which the easy axis of magnetization varies quasi-periodically giving rise to special domain configurations which are expected to markedly influence the mechanism of magnetization reversal and hysteresis behavior of these materials in bulk or thin films. The extraordinary permanent magnet properties exhibited by the well-known Co-Pt alloys as well as the Fe-Pt and Fe-Pd systems near the equiatomic composition derive from the formation of a polytwinned microstructure.
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department

(Time-resolved fluorescence studies of surface recombination in CdSe electrodes)

Description: The long range goal of our investigations is to understand the dynamics of heterogeneous electron transfer reactions. The primary method we use to monitor the carrier dynamics is the fluorescence of the bandgap emission. This all optical approach circumvents the limitations of photopotential and photocurrent methods. Before such studies on a reactive system can be informative, it is necessary to understand the dynamics of the photogenerated carriers under nonreactive conditions. Presently we are concentrating on carrier dynamics in the materials, cadmium selenide (CdSe) and cadmium sulfide (CdS). Under these conditions the carriers recombine either directly or through intragap electronic states. 2 refs., 1 fig.
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department

[Time-resolved optical studies of charge relaxation and charge transfer at electrode interfaces]

Description: Key components were identified in a quantitative model of carrier relaxation in semiconductor electrodes: nonlinear aspects of nonradiative and radiative recombination, effect of space charge field on carrier dynamics, self-absorption effects in direct gas semiconductors, and influence of surface state population kinetics on charge carrier recombination. For CdSe, the first three are operative (no direct proof of the last one). A realistic kinetic model for carrier recombination in the bulk of CdSe was used which includes important nonlinear effects, both radiative and nonradiative. The change in interfacial recombination velocity with the chemical nature of the sinterface was studied (n-CdSe/silane interfaces). Temperature effect (278 to 328 K) on fluorescence decay of n-CdSe in contact with 0.5 M KOH was found to be weak. An analytical solution was obtained for time-resolved fluoresence from electrodes under potential bias, and is being tested. Fluorescence work on a different material, CdS, indicate different recombination kinetics; this material was used to directly pump an optical transition of a surface state.
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department

[The physics of pattern formation of liquid interfaces]

Description: Energy consumption in fabrication of materials for all applications is process dependent. Improvements in the ability to process materials are of great importance to the DOE mission. This project addresses basic science questions related to the processing of materials and is aimed at understanding growth of interfaces and evolution of patterns on interfaces, both macroscopic and microscopic. Three laboratory experiments are proposed: A study of the changes in patterns available to the growth of a macroscopic interface when that interface is grown over one of a variety of microscopic'' lattices; a study of reversible aggregation of colloidal particles in a mixed solvent, and of the interactions and relaxations of both solvent and suspended particles when thermodynamic conditions are changed for a liquid matrix with suspended particles or fibres; and, an investigation of the sedimentation of particles in a quasi-two-dimensional viscous fluid, with attention both to the dynamics of the flow and to the roughness of the resulting surface of settled particles.
Date: January 1, 1993
Partner: UNT Libraries Government Documents Department

[Studies of supported hydrodesulfurization catalysis]

Description: Research progress is in three areas. First, correlation of the distribution of molybdenum oxidation states in reduced Mo/Al[sub 2]O[sub 3] catalysts with benzene hydrogenation activity. Second, the use of factor analysis curve-fitting to determine the distribution of molybdenum oxidation states educed Mo/TiO[sub 2] catalysts. Third, quantitative Raman and ESCA characterization of W/TiO[sub 2] catalysts.
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department

Computer simulations for the adsorption of polymers onto surfaces

Description: Polymer-surface interactions are important in every stage of oil and coal production, production of new energy-efficient composite materials, and in medicine. Therefore, it is important to isolate the factors that influence the interfacial activity of polymer chains. We developed theoretical models and computer simulations to determine effects of polymer architecture, solvent quality, and surface morphology on properties of chains at penetrable and impenetrable interfaces. 7 figs, 27 refs.
Date: January 1, 1993
Creator: Balazs, A.C.
Partner: UNT Libraries Government Documents Department

Electromagnetic dissociation of relativistic [sup 28]Si by nucleon emission

Description: A detailed study of the electromagnetic dissociation of [sup 28]Si by nucleon emission at E[sub lab]/A = 14.6 (GeV/nucleon was carried out with [sup 28]Si beams interacting on [sup 208]Pb). [sup 120]Sn. [sup 64]C targets. The measurements apparatus consists of detectors in the target area which measure the energy and charged multiplicity, and a forward spectrometer which measures the position, momentum and energy of the reaction fragments. The exclusive electromagnetic dissociation cross sections for decay channels having multiple nucleons in the final state have been measured which enables the selection of events produced in pure electromagnetic interactions. The measured cross sections agree well with previous measurements obtained for the removal of a few nucleons as well as with measurements on total charge removal cross sections from other experiments. The dependence of the integrated cross sections on the target charge Z[sub T] and the target mass AT confirms that for higher Z targets the excitation is largely electromagnetic. Direct measurements of the excitation energy for the electromagnetic dissociation of [sup 28]Si [yields] p+[sup 27]Al and [sup 28]Si [yields] n+[sup 27]Si have been obtained through a calculation of the invariant mass in kinematically, reconstructed events. The excitation energy spectrum for all targets peak near the isovector giant dipole resonance in [sup 28]Si. These distributions are well reproduced by combining the photon spectrum calculated using the Weizsaecker-Williams approximation with the experimental data on the photonuclear [sup 28]Si([sub [gamma],p])[sup 27]Al and [sup 28]Si([sub [gamma],n])[sup 27]Si. The possibilities of observing double giant dipole resonance excitations in [sup 28]Si have been investigated with cross section measurements as well as with excitation energy reconstruction.
Date: December 1, 1992
Creator: Sonnadara, U.J.
Partner: UNT Libraries Government Documents Department

New infrared photon absorption processes

Description: The fast ionization of atoms by very short laser pulses, and its possible suppression at extreme pulse intensities, is an active new field of investigation at present. Described is an investigation of whether past techniques for infrared laser multiphoton ionization of excited hydrogen atoms and of one-dimensional microwave ionization of highly excited hydrogen atoms can be combined and extended to address the new issues. Although technically difficult and requiring further improvement of apparatus, intense-field infrared laser experiments on excited hydrogen atoms are possible and can directly test theoretical and numerical results.
Date: May 1, 1993
Creator: Bayfield, J.E.
Partner: UNT Libraries Government Documents Department

Vibrational spectroscopic studies of surface chemical interactions in chemisorption and catalysis

Description: Various methods of vibrational spectroscopy are being employed to study the interaction and behavior of catalytically important species on both single crystal and high area catalytic surfaces. A number of interrelated themes are being investigated as shown below.
Date: January 1, 1991
Creator: Yates, J.T. Jr.
Partner: UNT Libraries Government Documents Department