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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
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
Simulation of longitudinal coupled-bunch instabilities (open access)

Simulation of longitudinal coupled-bunch instabilities

The purpose of this note is to document some work done as part of the effort directed at designing and simulating a bunch-by-bunch feedback system to control longitudinal coupled bunch instabilities in the B-factory. In particular, I discuss the ring model used in the simulation program developed to study this feedback system. Basically the simulation is a simple tracking program in which the rf drive voltage, the wakefields due to all the bunches, the synchrotron radiation losses, and the kicks applied to the bunches by the bunch-by-bunch feedback are all modelled as voltages applied at a single, discrete point in the ring. The computation of the bunch-by-bunch feedback voltages may of course be done by any desired algorithms. An example and discussion of the general behavior without bunch-by-bunch feedback is given at the end of this report.
Date: February 7, 1991
Creator: Thompson, K.A.
System: The UNT Digital Library
Petroleum marketing monthly, November 1991. [Contains glossary] (open access)

Petroleum marketing monthly, November 1991. [Contains glossary]

The Petroleum Marketing Monthly is designed to give information and statistical data about a variety of crude oils and refined petroleum products. The publication provides statistics on crude oil costs and refined petroleum products sales for use by industry, government, private sector analysts, educational institutions, and consumers. Data on crude oil include the domestic first purchase price, the f.o.b. and landed cost of imported crude oil, and the refiners' acquisition cost of crude oil. Sales data for motor gasoline, distillates, residuals, aviation fuels, kerosene, and propane are presented. 12 figs., 53 tabs.
Date: November 7, 1991
Creator: unknown
System: The UNT Digital Library
Colorado State University program for developing, testing, evaluating and optimizing solar heating and cooling systems (open access)

Colorado State University program for developing, testing, evaluating and optimizing solar heating and cooling systems

This report discusses the following tasks; solar heating with isothermal collector operation and advanced control strategy; solar cooling with solid desiccant; liquid desiccant cooling system development; solar house III -- development and improvement of solar heating systems employing boiling liquid collectors; generic solar domestic water heating systems; advanced residential solar domestic hot water (DHW) systems; management and coordination of Colorado State/DOE program; and field monitoring workshop.
Date: January 7, 1991
Creator: unknown
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.
System: The UNT Digital Library
Systematic preparation of selective heterogeneous catalysts (open access)

Systematic preparation of selective heterogeneous catalysts

The Single Turnover (STO) procedure, involving pulses of hydrogen and 1-butene, was developed for studying the types of active sites present on supported metal catalysts. The STO procedure was used to study direct saturated sites and other topics. Frontier molecular orbital studies were also made.
Date: November 7, 1991
Creator: Augustine, R.L.
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.
System: The UNT Digital Library
(Centralized reliability data organization for liquid metal reactor components) (open access)

(Centralized reliability data organization for liquid metal reactor components)

The Centralized Reliability Data Organization is a data bank and data analysis center, focusing on reliability, availability, and maintainability (RAM) data for components (e.g., valves, pumps, etc.) operating in liquid metal reactors and test facilities. PNC staff are using the CREDO data base as a resource for their development of a probabilistic safety assessment (PSA) for the MONJU fast breeder reactor now under construction. The meeting was held to discuss: (a) progress in FY 1989, (b) resolution of data base deficiencies and inconsistencies, (c) clarification of definitions for failure mode and failure cause, (d) component boundary definitions, (e) goals and objectives for the remainder of the fiscal year, and (f) proposals for future work. General agreement was reached on the need for improvements to the data base: resolution of data deficiencies and inconsistencies, reduction of the number of failure modes and causes, inclusion of failure severity, and a specific delineation of the boundary for each of the generic components. A schedule will be provided to PNC by 1 March 1991 addressing these issues. A proposal to develop a hybrid mainframe/PC reliability data base to improve user access was declined. A second proposal to develop a reliability data base for PNC's …
Date: February 7, 1991
Creator: Smith, M.S. & Manneschmidt, J.F.
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.
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
Working Group 7.1 on environmental transport, US-USSR Joint Coordinating Committee on Civilian Nuclear Reactor Safety. Progress report update (open access)

Working Group 7.1 on environmental transport, US-USSR Joint Coordinating Committee on Civilian Nuclear Reactor Safety. Progress report update

This report contains brief summaries of the status of projects of the Environmental Transport Group of the US-USSR Joint Coordinating Committee of Civilian Nuclear Reactor Safety. Projects reported on include: Management and Administration; Atmospheric Transport; Resuspension; External Dose; Terrestrial Food Chains; Aquatic Food Chains; Hydrological Transport; and Intercalibration
Date: September 7, 1991
Creator: Anspaugh, L. R. & Hendrickson, S. M.
System: The UNT Digital Library
[Report: Dallas Com] (open access)

[Report: Dallas Com]

A report on Ron Ruggless' commercial property including estimated value and tax information.
Date: January 7, 1991
Creator: unknown
System: The UNT Digital Library
TeV Beam Tubes Through D-0 End Calorimeter (open access)

TeV Beam Tubes Through D-0 End Calorimeter

None
Date: November 7, 1991
Creator: Leibfritz, J.R.
System: The UNT Digital Library
D to A Line Tuning (open access)

D to A Line Tuning

Although in the past the D to A line was well tuned, through the course of years of operations it has not kept up with changes in the Debuncher and Accumulator. The beam is now steered well off center in SEM's 806 and 807, and is possibly scraping in TQ5. In addition, there is some evidence that the beta functions are not matched, causing emmitance blowup of the beam. As the cycle time of the main ring has decreased these limitations have become a significant limitation to the stacking rate.
Date: May 7, 1991
Creator: Halling, Mike
System: The UNT Digital Library
Structural studies of the metal-rich region in the ternary Ta-Nb-S system (open access)

Structural studies of the metal-rich region in the ternary Ta-Nb-S system

Six new solid solution type compounds have been prepared using high temperature techniques and characterized by means of single crystal x-ray techniques during a study of the metal-rich region of the ternary Ta-Nb-S system. The structures of Nb{sub x}Ta{sub 11-x}S{sub 4} are reminiscent of niobium-rich sulfides, rather than of tantalum-rich sulfides. The coordinations of sulfur are capped trigonal prismatic while the metal coordinations are capped distorted cubic prismatic for Nb{sub x}Ta{sub 11-x}S{sub 4}, and capped distorted cubic prismatic and pentagonal prismatic for Nb{sub 12-x}Ta{sub x}S{sub 4}. The structures of Nb{sub x}Ta{sub 5-x}S{sub 2} contain homoatomic layers sequenced S-M3-M2-M1-M2-M3-S (M is mixed Nb, Ta) generating six-layer sheets, respectively. Weak S-S interactions at 3.26 and 3.19{Angstrom} between sheets contrast with the M-M binding within and between the sheets in these two novel layered compounds. The former are presumably responsible for the observed graphitic slippage of the samples. Nb{sub 21-x}Ta{sub x}S{sub 8} and Nb{sub x}Ta{sub 2-x}S are isostructural with Nb{sub 21}S{sub 8} and Ta{sub 2}S, respectively. Extended Hueckel band calculations were carried out for two layered compounds, Nb{sub x}Ta{sub 5-x}S{sub 2} (x {approx} 1.72) and Nb{sub x}ta{sub 2-x}S (x {approx} 0.95). Based upon band calculations metallic properties can be expected for these two …
Date: October 7, 1991
Creator: Yao, Xiaoqiang.
System: The UNT Digital Library
Systematic preparation of selective heterogeneous catalysts. Final report, September 1, 1984--August 31, 1991 (open access)

Systematic preparation of selective heterogeneous catalysts. Final report, September 1, 1984--August 31, 1991

The Single Turnover (STO) procedure, involving pulses of hydrogen and 1-butene, was developed for studying the types of active sites present on supported metal catalysts. The STO procedure was used to study direct saturated sites and other topics. Frontier molecular orbital studies were also made.
Date: November 7, 1991
Creator: Augustine, R. L.
System: The UNT Digital Library
(Limiting the greenhouse effect) (open access)

(Limiting the greenhouse effect)

Traveler attended the Dahlem Research Conference organized by the Freien Universitat, Berlin. The subject of the conference was Limiting the Greenhouse Effect: Options for Controlling Atmospheric CO{sub 2} Accumulation. Like all Dahlem workshops, this was a meeting of scientific experts, although the disciplines represented were broader than usual, ranging across anthropology, economics, international relations, forestry, engineering, and atmospheric chemistry. Participation by scientists from developing countries was limited. The conference was divided into four multidisciplinary working groups. Traveler acted as moderator for Group 3 which examined the question What knowledge is required to tackle the principal social and institutional barriers to reducing CO{sub 2} emissions'' The working rapporteur was Jesse Ausubel of Rockefeller University. Other working groups examined the economic costs, benefits, and technical feasibility of options to reduce emissions per unit of energy service; the options for reducing energy use per unit of GNP; and the significant of linkage between strategies to reduce CO{sub 2} emissions and other goals. Draft reports of the working groups are appended. Overall, the conference identified a number of important research needs in all four areas. It may prove particularly important in bringing the social and institutional research needs relevant to climate change closer to …
Date: January 7, 1991
Creator: Rayner, S.
System: The UNT Digital Library
Nucleon-Antinucleon Annihilation in Chiral Soliton Model (open access)

Nucleon-Antinucleon Annihilation in Chiral Soliton Model

We investigate annihilation process of nucleons in the chiral soliton model by the path integral method. A soliton-antisoliton pair is shown to decay into mesons at range of about 1fm, defined by the S{bar S} potential. Contribution of the annihilation channel to the elastic scattering is discussed.
Date: September 7, 1991
Creator: Musakhanov, M. M. & Musatov, I. V.
System: The UNT Digital Library
Japan's World War II Reparations: A Fact Sheet (open access)

Japan's World War II Reparations: A Fact Sheet

Japan's war reparations following World War II came in two stages. In the first, 1946-1949, U.S. and allied governments arranged for U.S. occupation authorities to ship about $160 million in Japanese industrial equipment to China, the Philippines, Indonesia, and the British colonies in East Asia.
Date: March 7, 1991
Creator: Niksch, Larry A.
System: The UNT Digital Library
Nucleon-antinucleon annihilation in chiral soliton model (open access)

Nucleon-antinucleon annihilation in chiral soliton model

We investigate annihilation process of nucleons in the chiral soliton model by the path integral method. A soliton-antisoliton pair is shown to decay into mesons at range of about 1fm, defined by the S{bar S} potential. Contribution of the annihilation channel to the elastic scattering is discussed.
Date: September 7, 1991
Creator: Musakhanov, M. M. & Musatov, I. V.
System: The UNT Digital Library
The Savannah River Site`s groundwater monitoring program: 1990 sampling schedule (open access)

The Savannah River Site`s groundwater monitoring program: 1990 sampling schedule

This schedule provides a final record of the 1990 sampling schedule for the SRS groundwater monitoring program conducted by the Environmental Protection Department/Environmental Section (EPD/EMS). It includes all the wells monitored by EPD/EMS at SRS during 1990 and identifies the constituents sampled, the sampling frequency, and the reasons for sampling. Sampling requests are incorporated into the schedule throughout the year. Drafts of the schedule are produced and revised quarterly.
Date: February 7, 1991
Creator: Rogers, C.D.
System: The UNT Digital Library