States

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.
Object Type: Report
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.
Object Type: Report
System: The UNT Digital Library
U.S. Customs Service: Update on the Merchandise Processing Fee (open access)

U.S. Customs Service: Update on the Merchandise Processing Fee

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on Custom Service's Merchandise Processing Fee (MPF) that is charged on certain imports, focusing on the relationship between the fee and the cost of services provided."
Date: October 7, 1999
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Influence of faults on groundwater flow and transport at YuccaMountain, Nevada (open access)

Influence of faults on groundwater flow and transport at YuccaMountain, Nevada

Numerical simulations of groundwater flow at Yucca Mountain, Nevada are used to investigate how faults influence groundwater flow pathways and regional-scale macrodispersion. The 3-D model has a unique grid block discretization that facilitates the accurate representation of the complex geologic structure present in faulted formations. Each hydrogeologic layer is discretized into a single layer of irregular and dipping grid blocks, and faults are discretized such that they are laterally continuous and varied in displacement varies along strike. In addition, the presence of altered fault zones is explicitly modeled, as appropriate. Simulations show that upward head gradients can be readily explained by the geometry of hydrogeologic layers, the variability of layer permeabilities, and the presence of permeable fault zones or faults with displacement only, not necessarily by upwelling from a deep aquifer. Large-scale macrodispersion results from the vertical and lateral diversion of flow near the contact of high- and low-permeability layers at faults, and from upward flow within high-permeability fault zones. Conversely, large-scale channeling can occur as a result of groundwater flow into areas with minimal fault displacement. Contaminants originating at the water table can flow in a direction significantly different from that of the water table gradient, and isolated zones …
Date: October 7, 1999
Creator: Cohen, Andrew J.B. & Sitar, Nicholas
Object Type: Report
System: The UNT Digital Library
Trace gas emission data bases for atmospheric chemistry studies (open access)

Trace gas emission data bases for atmospheric chemistry studies

Global data bases of trace gas emissions to the atmosphere have been compiled for the use in atmospheric chemistry studies. The resolution provided is a 1{degree} latitude by 1{degree} longitude. A series of 3 data bases has been provided. The first is an inventory of emissions of NO{sub x} from fossil fuel combustion, while the second is an inventory of SO{sub 2} emissions from the same anthropogenic source. The third database includes a global inventory of the emissions of NO{sub x} from terrestrial biomass burning and is given seasonally for the globe. The units of emission for the inventories are given as the mass in metric tons of N for the NO{sub x} inventories and metric tons of S for the SO{sub 2} inventory for each 1{degree} {times} 1{degree} grid. The emissions are expected to represent the emissions for the year 1980. The biomass burning source is given for 2 seasons where XXXXjul represents an ascii file containing the cumulated emissions for the months from April to September, and XXXXjan represents October to March. The grid for these data bases, (i,j) arrays, is (360,180), which represents 1 degree (lon,lat) resolution. The Table shows a description of each data base and …
Date: October 7, 1991
Creator: Dignon, J.
Object Type: Report
System: The UNT Digital Library
Reactor Restart Division trend analysis report, second quarter 1991 (open access)

Reactor Restart Division trend analysis report, second quarter 1991

This document provides a trend analysis for the Savannah River Reactor Restart Program. The data contained in this report is comprised of Nonconformance Report (NCR), Surveillance Reports, and Corrective Action Reports (CAR). The data trended now includes six quarters and provides the capability of looking at changing patterns in the various performance categories over time.
Date: October 7, 1991
Creator: Castles, R.B.
Object Type: Report
System: The UNT Digital Library
Electrochemical processing of nitrate waste solutions (open access)

Electrochemical processing of nitrate waste solutions

The second phase of research performed at The Electrosynthesis Co., Inc. has demonstrated the successful removal of nitrite and nitrate from a synthetic effluent stream via a direct electrochemical reduction at a cathode. It was shown that direct reduction occurs at good current efficiencies in 1,000 hour studies. The membrane separation process is not readily achievable for the removal of nitrites and nitrates due to poor current efficiencies and membrane stability problems. A direct reduction process was studied at various cathode materials in a flow cell using the complete synthetic mix. Lead was found to be the cathode material of choice, displaying good current efficiencies and stability in short and long term tests under conditions of high temperature and high current density. Several anode materials were studied in both undivided and divided cell configurations. A divided cell configuration was preferable because it would prevent re-oxidation of nitrite by the anode. The technical objective of eliminating electrode fouling and solids formation was achieved although anode materials which had demonstrated good stability in short term divided cell tests corroded in 1,000 hour experiments. The cause for corrosion is thought to be F[sup [minus]] ions from the synthetic mix migrating across the cation …
Date: October 7, 1992
Creator: Genders, D.; Weinberg, N. & Hartsough, D. (Electrosynthesis Co., Inc., Cheektowaga, NY (United States))
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 19, Number 75, Pages 7953-8078, October 7, 1994 (open access)

Texas Register, Volume 19, Number 75, Pages 7953-8078, October 7, 1994

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: October 7, 1994
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
Reactor Restart Division trend analysis report, second quarter 1991 (open access)

Reactor Restart Division trend analysis report, second quarter 1991

This document provides a trend analysis for the Savannah River Reactor Restart Program. The data contained in this report is comprised of Nonconformance Report (NCR), Surveillance Reports, and Corrective Action Reports (CAR). The data trended now includes six quarters and provides the capability of looking at changing patterns in the various performance categories over time.
Date: October 7, 1991
Creator: Castles, R. B.
Object Type: Report
System: The UNT Digital Library
The Savannah River Site`s Groundwater Monitoring Program: Second quarter 1992 (open access)

The Savannah River Site`s Groundwater Monitoring Program: Second quarter 1992

The Environmental Protection Department/Environmental Monitoring Section (EPD/EMS) administers the Savannah River Site`s (SRS) Groundwater Monitoring Program. During second quarter 1992, EPD/EMS conducted extensive sampling of monitoring wells. EPD/EMS established two sets of criteria to assist in the management of sample results. The flagging criteria do not define contamination levels; instead, they aid personnel in sample scheduling, interpretation of data, and trend identification. Since 1991, the flagging criteria have been based on the federal Environmental Protection Agency (EPA) drinking water standards and on method detection limits. A detailed explanation of the current flagging criteria is presented in the Flagging Criteria section of this document. Analytical results from second quarter 1992 are listed in this report.
Date: October 7, 1992
Creator: Rogers, C. D.
Object Type: Report
System: The UNT Digital Library
PXAMS -- Projectile X ray AMS: X ray yields and applications (open access)

PXAMS -- Projectile X ray AMS: X ray yields and applications

Characteristic x rays have recently been explored as a method for the detection and identification of ions in accelerator mass spectrometry (AMS). After analysis in the AMS spectrometer, the ions stop in an appropriately chosen target and the induced x rays identify the ions by atomic number. For the application of AMS to higher mass isotopes, characteristic x rays allow significantly better discrimination of competing atomic isobars than is possible using energy loss detectors. Characteristic x rays also show promise as a convenient component in hybrid detection systems. Measurements of x ray yields are presented for Si, Fe, Ni, Se, Mo, and Pd ions of 0.5--2 MeV/AMU. The yields rise by more than a factor of 10 over this energy range, and approach 1 x-ray per incident ion at 2 MeV/AMU for the lighter ions. Preliminary work on the application of PXAMS to the detection of {sup 79}Se is described.
Date: October 7, 1994
Creator: McAninch, J. E.; Bench, G. S.; Freeman, S. P. H. T.; Roberts, M. L.; Southon, J. R.; Vogel, J. S. et al.
Object Type: Report
System: The UNT Digital Library
ARAC: A flexible real-time dose consequence assessment system (open access)

ARAC: A flexible real-time dose consequence assessment system

Since its beginning, the Atmospheric Release Advisory Capability (ARAC), an emergency radiological dose assessment service of the US Government, has been called on to do consequence assessments for releases into the atmosphere of radionuclides and a variety of other substances. Some of the more noteworthy emergency responses have been for the Three Mile Island and Chernobyl nuclear power reactor accidents, and more recently, for a cloud of gases from a rail-car spill into the Sacramento river of the herbicide metam sodium, smoke from hundreds of burning oil wells in Kuwait, and ash clouds from the eruption of Mt. Pinatubo. The spatial scales of these responses range from local, to regional, to global, and the response periods from hours, to weeks, to months. Because of the variety of requirements of each unique assessment, ARAC has developed and maintains a flexible system of people, computer software and hardware.
Date: October 7, 1993
Creator: Ellis, J. S. & Sullivan, T. J.
Object Type: Article
System: The UNT Digital Library
Spool assembly support analysis (open access)

Spool assembly support analysis

This document provides the wind/seismic analysis and evaluation for the pump pit spool assemblies. Hand calculations were used for the analysis. UBC, AISC, and load factors were used in this evaluation. The results show that the actual loads are under the allowable loads and all requirements are met.
Date: October 7, 1994
Creator: Norman, B. F.
Object Type: Report
System: The UNT Digital Library
Thermodynamic analysis of actinide volatilities for the thermal processor units in the ITTS study (open access)

Thermodynamic analysis of actinide volatilities for the thermal processor units in the ITTS study

Available thermodynamic data for volatilization of U and Pu gaseous species under oxidizing conditions are tabulated: UO{sub 3}, UO{sub 2}(OH){sub 2}, UO{sub 2}F{sub 2}, PuO{sub 3}, PuO{sub 2}(OH){sub 2}. Results of a thermodynamic analysis of U, Pu, and Am volatilities in the secondary combustor, plasma arc process, and vitrifier are given.
Date: October 7, 1993
Creator: Krikorian, O. H.
Object Type: Report
System: The UNT Digital Library
Characterization of 618-11 solid waste burial ground, disposed waste, and description of the waste generating facilities (open access)

Characterization of 618-11 solid waste burial ground, disposed waste, and description of the waste generating facilities

The 618-11 (Wye or 318-11) burial ground received transuranic (TRTJ) and mixed fission solid waste from March 9, 1962, through October 2, 1962. It was then closed for 11 months so additional burial facilities could be added. The burial ground was reopened on September 16, 1963, and continued operating until it was closed permanently on December 31, 1967. The burial ground received wastes from all of the 300 Area radioactive material handling facilities. The purpose of this document is to characterize the 618-11 solid waste burial ground by describing the site, burial practices, the disposed wastes, and the waste generating facilities. This document provides information showing that kilogram quantities of plutonium were disposed to the drum storage units and caissons, making them transuranic (TRU). Also, kilogram quantities of plutonium and other TRU wastes were disposed to the three trenches, which were previously thought to contain non-TRU wastes. The site burial facilities (trenches, caissons, and drum storage units) should be classified as TRU and the site plutonium inventory maintained at five kilograms. Other fissile wastes were also disposed to the site. Additionally, thousands of curies of mixed fission products were also disposed to the trenches, caissons, and drum storage units. Most …
Date: October 7, 1997
Creator: Hladek, K. L.
Object Type: Report
System: The UNT Digital Library
Texas Attorney General Opinion: DM-259 (open access)

Texas Attorney General Opinion: DM-259

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification; Whether a member of an appraisal review board may appear before the board either in a capacity as a court-appointed receiver or a registered property tax consultant without violating conflict-of-interest laws and related questions (RQ-507, ID# 18811)
Date: October 7, 1993
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: JC-122 (open access)

Texas Attorney General Opinion: JC-122

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, John Cornyn, regarding a legal question submitted for clarification: Whether a purchase from jail-commissary proceeds is subject to statutory competitive procurement requirements.
Date: October 7, 1999
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: JC-123 (open access)

Texas Attorney General Opinion: JC-123

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, John Cornyn, regarding a legal question submitted for clarification: Whether a county officer may be credited or compensated for unused vacation time he earned while a county employee.
Date: October 7, 1999
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: JC-124 (open access)

Texas Attorney General Opinion: JC-124

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, John Cornyn, regarding a legal question submitted for clarification: Whether Texas Department of Transportation may restrict material specifications to products of only one vendor if other vendors have similar products of equal quality, and related questions.
Date: October 7, 1999
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: LO92-062 (open access)

Texas Attorney General Opinion: LO92-062

Letter opinion issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification: Kinds of evidence a notary public may accept for the purpose of acknowledging a written instrument (ID# 16743)
Date: October 7, 1992
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: LO92-063 (open access)

Texas Attorney General Opinion: LO92-063

Letter opinion issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification: Whether a physician who monitors the treatment of a patient in an ambulance by telemetry “attends” that patient for purposes of section 6 of article 49.25 of the Code of Criminal Procedure (ID# 16514)
Date: October 7, 1992
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Texas Attorney General Opinion: LO93-088 (open access)

Texas Attorney General Opinion: LO93-088

Letter opinion issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification: Removal of criminal record subject to expunction order from agency files (ID# 18550)
Date: October 7, 1993
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Obstruction of Justice Under Federal Law: An Abbreviated Sketch (open access)

Obstruction of Justice Under Federal Law: An Abbreviated Sketch

This report focuses on selected aspects of the general obstruction of justice provisions found in 18 U.S.C. 1503, 1505, and 1512. It is essentially a replica, without footnotes or citations, of CRS Report 98-832, Obstruction of Justice Under Federal Law: A Review of Some of the Elements.
Date: October 7, 1998
Creator: Doyle, Charles
Object Type: Report
System: The UNT Digital Library
Measurement of the Angular Distribution of the Electron From W {r_arrow} E = {Nu} decay, in P{Anti P} at {Radical}S = 1.8 Tev, as Function of P{Sub T}{Sup W}; Medida De La Distribucion Angular Del Electron De W en E + Neutrino en P{Anti P} a 1.8 Tev (open access)

Measurement of the Angular Distribution of the Electron From W {r_arrow} E = {Nu} decay, in P{Anti P} at {Radical}S = 1.8 Tev, as Function of P{Sub T}{Sup W}; Medida De La Distribucion Angular Del Electron De W en E + Neutrino en P{Anti P} a 1.8 Tev

The goal of this work was to study the behavior of the angular distribution of the electron form the decay of the W boson in a specific rest-frame of the W, the Collins-Soper frame. This thesis consists of four major divisions, each dealing with closely related themes: (a) Physics Background, (b) Description of the Hardware and General Software Tools, (c) Description of the Analysis and Specific Tools, and (d) Results and Conclusions. Each division is comprised of one or more chapters and each chapter is divided into sections and subsections.
Date: October 7, 1996
Creator: Ramos, M. I. M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library