Resource Type

Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties (open access)

Exploring novel silicon-containing polymers---From preceramic polymers to conducting polymers with nonlinear optical properties

Several new types of silicon-containing preceramic polymers, i.e., poly(diorganosilacetylene) and poly(diorganosilvinylene) have been synthesized with molecular weights from 10,000 to 120,000. These polymers could be thermally converted to SiC with a moderate to high char yields. Ready solubility and good processability made these types of polymers attractive in their applications to ceramics. The thermal polymerization of diethynyldiphenyl-silane, which was reported in 1968 to afford poly(diphenylsilyldiacetylene) via dehydrogenation, was reinvestigated. Spectroscopic studies showed that the polymer had a structure of polyacetylene type not diacetylene. Diphenyldiethynylgermane and a series of diorganodiethynylsilances were synthesized. These could be polymerized in the presence of MoCl{sub 5} or WCl{sub 6} to afford a soluble, violet material with Mw as high as 108,000. 100 refs., 56 figs., 16 tabs.
Date: October 7, 1991
Creator: Pang, Yi.
System: The UNT Digital Library
A miniature inexpensive, oxygen sensing element (open access)

A miniature inexpensive, oxygen sensing element

An exhaustive study was conducted to determine the feasibility of Nernst-type oxygen sensors based on ceramics containing Bi{sub 2}O{sub 3}. The basic sensor design consisted of a ceramic sensing module sealed into a metal tube. The module accommodated an internal heater and thermocouple. Thermal-expansion-matched metals, adhesives, and seals were researched and developed, consistent with sequential firings during sensor assembly. Significant effort was devoted to heater design/testing and to materials' compatibility with Pt electrodes. A systematic approach was taken to develop all sensor components which led to several design modifications. Prototype sensors were constructed and exhaustively tested. It is concluded that development of Nerst-type oxygen sensors based on Bi{sub 2}O{sub 3} will require much further effort and application of specialized technologies. However, during the course of this 3-year program much progress was reported in the literature on amperometric-type oxygen sensors, and a minor effort was devoted here to this type of sensor based on Bi{sub 2}O{sub 3}. These studies were made on Bi{sub 2}O{sub 3}-based ceramic samples in a multilayer-capacitor-type geometry and amperometric-type oxygen sensing was demonstrated at very low temperatures ({approximately} 160{degree}C). A central advantage here is that these types of sensors can be mass-produced very inexpensively ({approximately} 20--50 cents …
Date: October 7, 1991
Creator: Arenz, R. W.
System: The UNT Digital Library
Acceleration using total internal reflection (open access)

Acceleration using total internal reflection

This report considers the use of a dielectric slab undergoing total internal reflection as an accelerating structure for charged particle beams. We examine the functional dependence of the electromagnetic fields above the surface of the dielectric for polarized incident waves. We present an experimental arrangement for testing the performance of the method, using apparatus under construction for the Grating Acceleration experiment at Brookhaven National Laboratory. 13 refs., 4 figs., 2 tabs.
Date: June 7, 1991
Creator: Fernow, R.C.
System: The UNT Digital Library
Clean gasoline reforming with superacid catalysts (open access)

Clean gasoline reforming with superacid catalysts

Tasks reported on this term include optimization of chlorided Pt- alumina catalysts, testing of the optimum Pt/Cl alumina catalysts, preparation and testing of zirconia superacid catalyst. (VC)
Date: May 7, 1992
Creator: Davis, B. H.
System: The UNT Digital Library
Gaseous phase coal surface modification (open access)

Gaseous phase coal surface modification

In this report, we present an improved, feasible and potentially cost effective method of cleaning and beneficiating ultrafine coal. Increased mechanization of mining methods and the need towards depyritization, and demineralization have led to an increase in the quantity of coal fines generated in recent times. For example, the amount of {minus}100 mesh coal occurring in coal preparation plant feeds now typically varies from 5 to 25% of the total feed. Environmental constraints coupled with the greatly increased cost of coal have made it increasingly important to recover more of these fines. Our method chemically modifies the surface of such coals by a series of gaseous phase treatments employing Friedel-Crafts reactions. By using olefins (ethene, propene and butene) and hydrogen chloride catalyst at elevated temperature, the surface hydrophobicity of coal is enhanced. This increased hydrophobicity is manifest in surface phenomena which reflect conditions at the solid/liquid interphase (zeta potential) and those which reflect conditions at the solid/liquid/gas interphases (contact angle, wettability and floatability).
Date: May 7, 1992
Creator: Okoh, J.M.; Pinion, J. & Thiensatit, S.
System: The UNT Digital Library
Liquid chromatographic analysis of coal surface properties (open access)

Liquid chromatographic analysis of coal surface properties

The main objectives of this proposed research work are to refine further the inverse liquid chromatography technique for the study of surface properties of raw coals, treated coals and coal minerals in water, to evaluate relatively surface properties of raw coals, treated coals and coal minerals by inverse liquid chromatography, and to evaluate flotability of various treated coals in conjunction with surface properties of coals. Coals such as Pittsburgh seam coal, Illinois No. 6 coal, Wyodak coal are chosen as representatives of high-rank bituminous coal, high volatile bituminous coal and subbituminous coal, respectively. Coal minerals such as pyrite and dolomite are chosen as representative coal minerals.
Date: April 7, 1992
Creator: Kwon, K.C.
System: The UNT Digital Library
Department of Energy Workforce Reduction: Community Assistance Can Be Better Targeted (open access)

Department of Energy Workforce Reduction: Community Assistance Can Be Better Targeted

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO reviewed the Department of Energy's (DOE) community assistance program for minimizing the impact of downsizing its contractor workforce, focusing on: (1) how much funding DOE had committed to spend and spent in support of its worker and community assistance program for fiscal years (FY) 1994 through 1998; (2) who received benefits during FY 1997 and FY 1998; (3) comparing DOE's separation benefits with the benefit packages of other federal and nonfederal organizations; and (4) what effect DOE's criteria had on determining which communities received assistance."
Date: May 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Combating Terrorism: Need for Comprehensive Threat and Risk Assessments of Chemical and Biological Attacks (open access)

Combating Terrorism: Need for Comprehensive Threat and Risk Assessments of Chemical and Biological Attacks

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO reviewed the scientific and practical aspects of a terrorist carrying out large-scale chemical or biological attacks on U.S. soil, focusing on the: (1) technical ease or difficulty for terrorists to acquire, process, improvise, and disseminate certain chemical and biological agents; and (2) extent to which the U.S. government has assessed the threats and risks posed by chemical and biological terrorism in the United States to serve as a basis for planned investments."
Date: September 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Mental Health: Improper Restraint or Seclusion Use Places People at Risk (open access)

Mental Health: Improper Restraint or Seclusion Use Places People at Risk

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on inpatient and residential treatment facilities' use of restraints or seclusion as a means of treating mental patients, focusing on the: (1) dangers of restraint and seclusion, the extent to which restraint and seclusion are used in inpatient and residential treatment facilities for individuals with mental illness or mental retardation, and the number of related injuries and deaths; (2) federal and state policies that govern the use of restraint and seclusion in inpatient or residential treatment facilities for individuals with mental illness or mental retardation; and (3) experiences of states that have instituted regulations and reporting requirements to address the use of restraint and seclusion."
Date: September 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Crime Technology: Federal Assistance to State and Local Law Enforcement (open access)

Crime Technology: Federal Assistance to State and Local Law Enforcement

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the crime technology assistance provided by the federal government to state and local law enforcement agencies for fiscal years 1996 through 1998, focusing on the types and amounts of assistance provided by the Department of Justice (DOJ), the Department of the Treasury, and the Office of National Drug Control Policy (ONDCP)."
Date: June 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Agriculture In Transition: Farmers' Use of Risk Management Strategies (open access)

Agriculture In Transition: Farmers' Use of Risk Management Strategies

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Agriculture's (USDA) efforts to educate farmers about risk management, focusing on: (1) the extent of farmers' use of risk management tools; and (2) educational programs and projects USDA has directed or initiated to prepare farmers for managing risks and determining the groups or individuals who have participated in or been served by these programs."
Date: April 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
General Services Administration: Information on Pricing Retail Packaging Products (open access)

General Services Administration: Information on Pricing Retail Packaging Products

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO examined the General Services Administration's (GSA) retail packaging products program, focusing on whether: (1) GSA is required by law to set its prices for retail packaging products at levels sufficient to ensure that all selling costs are recovered on each item; and (2) GSA's selling prices for these items do recover all costs."
Date: July 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
National Laboratories: DOE Needs to Assess the Impact of Using Performance-Based Contracts (open access)

National Laboratories: DOE Needs to Assess the Impact of Using Performance-Based Contracts

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Energy's (DOE) progress in implementing performance-based contracting at its national laboratories, focusing on: (1) the status of performance-based contracting in DOE's national laboratory contracts; and (2) DOE's efforts to determine the impact of performance-based contracting."
Date: May 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Results Act: Observations on the Department of Transportation's Fiscal Year 2000 Performance Plan (open access)

Results Act: Observations on the Department of Transportation's Fiscal Year 2000 Performance Plan

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the Department of Transportation's (DOT) performance plan for fiscal year (FY) 2000, focusing on: (1) the usefulness of DOT's plan in providing a clear picture of intended performance across the Department; (2) the strategies and resources that DOT will use to achieve its goals; and (3) whether DOT's performance information will be credible."
Date: May 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Results Act: Observations on the U.S. Department of Agriculture's Fiscal Year 2000 Performance Plan (open access)

Results Act: Observations on the U.S. Department of Agriculture's Fiscal Year 2000 Performance Plan

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Agriculture's (USDA) performance plan for fiscal year (FY) 2000, focusing on the extent to which the plan: (1) provides a clear picture of intended performance across the Department; (2) discusses the strategies and resources USDA will use to achieve its goals; and (3) provides confidence that the performance information will be credible."
Date: June 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Military Infrastructure: Real Property Management Needs Improvement (open access)

Military Infrastructure: Real Property Management Needs Improvement

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the Department of Defense's (DOD) management of the maintenance of its real properties, focusing on: (1) how the services determine and prioritize maintenance and repair requirements and how they allocate resources to meet their needs; (2) promising practices in facility management that the services could consider; and (3) barriers to implementing promising practices and ways to address them."
Date: September 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
General Aviation Airports: Unauthorized Land Use Highlights Need for Improved Oversight and Enforcement (open access)

General Aviation Airports: Unauthorized Land Use Highlights Need for Improved Oversight and Enforcement

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO provided information on: (1) the Federal Aviation Administration's (FAA) monitoring of general aviation airports' compliance with federal land-use requirements; and (2) FAA's use of enforcement tools to resolve cases of noncompliance."
Date: May 7, 1999
Creator: United States. General Accounting Office.
System: The UNT Digital Library
Clean Coal Technology III (CCT III) 10 MW demonstration of gas suspension absorption (open access)

Clean Coal Technology III (CCT III) 10 MW demonstration of gas suspension absorption

The Gas Suspension Absorber (GSA) system brings coal combustion gases into contact with a suspended mixture of solids, including sulfur-absorbing lime. After the lime absorbs the sulfur pollutants, the solids are separated from the gases in a cyclone device and recirculated back into the system where they capture additional sulfur pollutant. The cleaned flue gases are sent through a dust collector before being released into the atmosphere. The key to the system's superior economic performance with high sulfur coals is the recirculation of solids. Typically, a solid particle will pass through the system about one hundred times before leaving the system. Another advantage of the GSA system is that a single spray nozzle is used to inject fresh lime slurry. The GSA system is expected to be the answer to the need of the US industry for an effective, economic and space efficient solution to the SO{sub 2} pollution problem.
Date: February 7, 1992
Creator: unknown
System: The UNT Digital Library
Enhancing the use of coals by gas reburning-sorbent injection (open access)

Enhancing the use of coals by gas reburning-sorbent injection

Clean Coal Technology implies the use of coal in an environmentally acceptable manner. Coal combustion results in the emission of two types of acid rain precursors: oxides of sulfur (SO{sub x}) and oxides of nitrogen (NO{sub x}). This Clean Coal Technology project will demonstrate a combination of two developed technologies to reduce both NO{sub x} and SO{sub x} emissions: gas reburning and calcium based dry sorbent injection. The demonstrations will be conducted on two pre-NSPS utility boilers representative of the US boilers which contribute significantly to the inventory of acid rain precursor emissions: tangentially and cyclone fired units. Because of cost growth and lack of available funding, no further work has been done after Phase 1 at site B; the wall fired unit.
Date: February 7, 1992
Creator: unknown
System: The UNT Digital Library
Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. [Pseudomonas, Thiobacillus, Rhodococcus] (open access)

Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. [Pseudomonas, Thiobacillus, Rhodococcus]

The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate ( 4S'') pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a fermentor'' for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.
Date: February 7, 1992
Creator: Krawiec, S.
System: The UNT Digital Library
The Savannah River Site's Groundwater Monitoring Program, second quarter 1990 (open access)

The Savannah River Site's Groundwater Monitoring Program, second quarter 1990

The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site's (SRS) Groundwater Monitoring Program. During second quarter 1990 (April through June) EPD/EMS conducted routine sampling of monitoring wells and drinking water locations. EPD/EMS established two sets of flagging criteria in 1986 to assist in the management of sample results. The flagging criteria aid personnel in sample scheduling, interpretation of data, and trend identification. The flagging criteria are based on detection limits, background levels in SRS groundwater, and drinking water standards. An explanation of flagging criteria for the second quarter is presented in the Flagging Criteria section of this document. All analytical results from second quarter 1990 are listed in this report.
Date: February 7, 1991
Creator: unknown
System: The UNT Digital Library
Investigative Oversight: An Introduction to the Law, Practice and Procedure of Congressional Inquiry (open access)

Investigative Oversight: An Introduction to the Law, Practice and Procedure of Congressional Inquiry

This report provides an overview of some of the more common legal, procedural, and practical issues, questions and problems that committees have faced in the courts of an oversight investigation.
Date: April 7, 1995
Creator: Rosenberg, Morton
System: The UNT Digital Library
Military Retirement and Veterans' Compensation: Concurrent Receipt Issues (open access)

Military Retirement and Veterans' Compensation: Concurrent Receipt Issues

This report describes the history and background of the offset and the legislative history of recent attempts to eliminate or reduce the offset. It delineates and analyzes the arguments for and against eliminating or reducing the offset and allowing concurrent receipt, and addresses the issues of costs, precedents in other Federal programs, purposes of the two programs, and equity issues. Finally, options other than full concurrent receipt are mentioned.
Date: April 7, 1995
Creator: Goldich, Robert L.
System: The UNT Digital Library
The Endangered Species Act and Private Property (open access)

The Endangered Species Act and Private Property

If the 103rd Congress embarks upon an effort to reauthorize the Endangered Species Act (ESA), it will run into an old acquaintance: the property rights issue. As now written, the ESA has at least the potential to curtail property rights (whatever its actual impact as implemented may be). This report explores the legal repercussions of those impacts, especially whether they constitute takings of property under the fifth amendment of the U.S. Constitution.
Date: March 7, 1993
Creator: Meltz, Robert
System: The UNT Digital Library