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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.
Object Type: Report
System: The UNT Digital Library
Low-cost solar array project. Task I. Silicon material. Investigation of the hydrogenation of SiCl/sub 4/ (open access)

Low-cost solar array project. Task I. Silicon material. Investigation of the hydrogenation of SiCl/sub 4/

Reaction kinetic measurements on the hydrochlorination of SiCl/sub 4/ and m.g. silicon metal were last reported as a function of reaction temperature, reactor pressure, H/sub 2//SiCl/sub 4/ ratio and silicon metal particle size distribution, 3 SiCl/sub 4/ + 2 H/sub 2/ + Si reversible 4 SiHCl/sub 3/. The effect of impurities in the m.g. silicon metal on the rate of this reaction has been investigated in this quarter. The m.g. silicon was replaced with high purity, electronic grade silicon metal in the hydrochlorination reaction. With electronic grade Si, the reaction rate was found to be about one order of magnitude slower than those obtained with m.g. silicon metal. These metallic impurities in the m.g. silicon appear to have a catalytic effect. Addition of 5 wt% cuprous chloride to the electronic grade Si mass bed increased the reaction rate to the same level as those obtained with m.g. silicon with 5% CuCl added. The effect of prolonged reaction time on the hydrochlorination reaction was studied. The plan is to run the reaction for long periods of time with the objective of studying the life of the Si mass bed. No significant change in the reaction rate was observed after about 80 …
Date: October 7, 1980
Creator: Mui, J. Y. P. & Seyferth, D.
Object Type: Report
System: The UNT Digital Library
Some Scoping Experiments for a Space Reactor (open access)

Some Scoping Experiments for a Space Reactor

Some scoping experiments were performed to evaluate fuel performance in a lithium heat pipe reactor operating at a nominal 1500K heat pipe temperature. Fuel-coolant and fuel-coolant-clad relationships showed that once a failed heat pipe occurs temperatures can rise high enough so that large concentrations of uranium can be transported by the vapor phase. Upon condensation this uranium would be capable of penetrating heat pipes adjacent to the failed pipe. The potential for propagation of failure exists with UO/sub 2/ and a lithium heat pipe. Changing the composition of the metal of the heat pipe would have only a second order effect on the kinetics of the failure mechanism. Uranium carbide and nitride were considered as potential fuels which are nonreactive in a lithium environment. At high temperatures the nitride would be favored because of its better compatibility with potential cladding materials. Compositions of UN with small additions of YN appear to offer very attractive properties for a compact high temperature high power density reactor.
Date: July 7, 1983
Creator: Alexander, C. A. & Ogden, J. S.
Object Type: Report
System: The UNT Digital Library
Federal Government Health, Education, and Welfare Programs of Assistance to American Indians Residing on Federal Reservations (open access)

Federal Government Health, Education, and Welfare Programs of Assistance to American Indians Residing on Federal Reservations

This report lists and describes federal health, education, and welfare programs available to Native Americans living on federal reservations.
Date: October 7, 1969
Creator: Langone, Stephen A.
Object Type: Report
System: The UNT Digital Library
References to Safeguards, Physical Security, and Related Matters in the Nuclear Non-proliferation Act of 1978 (P.L. 95-242) (open access)

References to Safeguards, Physical Security, and Related Matters in the Nuclear Non-proliferation Act of 1978 (P.L. 95-242)

This report includes tables and excerpts of references to safeguards, physical security, and related matters in the Nuclear Non-proliferation Act of 1978.
Date: July 7, 1978
Creator: Kramer, Donna S. & Donnelly, Warren H.
Object Type: Report
System: The UNT Digital Library
Mineral Resources of the United States Continental Shelf: Some Common Questions (open access)

Mineral Resources of the United States Continental Shelf: Some Common Questions

This report answers some frequently asked questions regarding the mineral resources of the continental shelf of the United States
Date: August 7, 1970
Creator: Siehl, George H.
Object Type: Report
System: The UNT Digital Library
[News Script: Dow Jones] (open access)

[News Script: Dow Jones]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 7, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Hopstadter] (open access)

[News Script: Hopstadter]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: November 7, 1968
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Baseball] (open access)

[News Script: Baseball]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 7, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Dallas council] (open access)

[News Script: Dallas council]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: October 7, 1968
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Paul Eggers] (open access)

[News Script: Paul Eggers]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 7, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Painters] (open access)

[News Script: Painters]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: December 7, 1968
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Dayton, Colorado State] (open access)

[News Script: Dayton, Colorado State]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 7, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Tower] (open access)

[News Script: Tower]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 7, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Citrus Golf] (open access)

[News Script: Citrus Golf]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 7, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Citrus Open] (open access)

[News Script: Citrus Open]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 7, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Death] (open access)

[News Script: Death]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: October 7, 1968
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: City council filings] (open access)

[News Script: City council filings]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 7, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[News Script: Bert Yancey] (open access)

[News Script: Bert Yancey]

Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: March 7, 1969
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Object Type: Script
System: The UNT Digital Library
[Letter from Marvin E. Edwards to Bill McCarter, February 7, 1992] (open access)

[Letter from Marvin E. Edwards to Bill McCarter, February 7, 1992]

Photocopy of a letter from Marvin E. Edwards, General Superintendent, Dallas ISD, to Bill McCarter, co-director for North Texas Institute for Educators on the Visual Arts. Thanking McCarter for his letter of January 10, 1992 requesting the attendance of Janice Wiggins, Visual Arts Specialist for the DISD at the National Art Education Association Conference, which Edwards is pleased to have her participate in the DBAE report. Edwards also is in support of the discipline-based approach to teaching of the art as it not only encourages studio art training but reinforces other goals like improved reading, interdisciplinary studies and high lever activities. Edwards is pleased with the program and what opportunities it offers their students.
Date: February 7, 1992
Creator: Edwards, Marvin E.
Object Type: Letter
System: The UNT Digital Library
[RE: "Achieving National Education Reform: Arts Education as Catalyst," January 7, 1993] (open access)

[RE: "Achieving National Education Reform: Arts Education as Catalyst," January 7, 1993]

Photocopy of a letter from Vicki Rosenberg, program officer of the Getty Center, to the Regional and Californian Institute Exhibition Staff. In regards to "Achieving National Education Reform: Art Education as Catalyst" conference being held at San Francisco Hilton and Towers, February 3, 1993. The letter holds information about travel arrangements needed to be made before January 20th, hotel reservations and notification that the Getty center will cover the cost of lodging, incidental expenses that the center will reimburse related to the attendance at the conference, including meals and transportation from airport, exhibition staff duties being members of the regional institute, and conference registration. Enclosed with the invitation, are a schedule of the conference for the exhibit staff and an agenda list.
Date: January 7, 1993
Creator: Rosenberg, Vicki
Object Type: Letter
System: The UNT Digital Library
[Letter from Nancy Reynolds to Nancy Ruff, May 7, 1993] (open access)

[Letter from Nancy Reynolds to Nancy Ruff, May 7, 1993]

Photocopy of a letter from Nancy Reynolds, project coordinator of North Texas Institute for Educators on the Visual Arts, to Nancy Ruff, Hurst-Euless-Bedford ISD. In regards to a letter that Bill McCarter and Jack Davis wrote to Russ Chapman, Principal of Lakewood Elementary School, to congratulate Chapman on being selected by the Getty Institute to attend a National Administrators Focus Group Conference. Reynolds informs Ruff that Chapman will give presentations on two different days about the importance of arts in education, June 8th and June 14th.
Date: May 7, 1993
Creator: Reynolds, Nancy
Object Type: Letter
System: The UNT Digital Library
[Letter from Jack Davis to Janice Wiggins, April 7, 1995] (open access)

[Letter from Jack Davis to Janice Wiggins, April 7, 1995]

Photocopy of a letter from Jack Davis, co-director of North Texas Institute for Educators on the Visual Arts, to Janice Wiggins, Dallas ISD. Discussing the use of grant money. Wiggins requested that the grant money, intended to be used for support of Dallas I.S.D's participation in the Secondary Institute be used to stipends for participants of the Elementary Institute instead. Davis writes back that this is not possible for several reason which he encloses in the letter, the first being that he does not want to jeopardize the relationship with his funders by using the grants for something that was not made clear in the condition when the money was given. Davis explains that if the money is not used for its original intended purpose for which they were in agreement, then they are obligated to return the money back. Copied on the letter is Bill Cormack.
Date: April 7, 1995
Creator: Davis, Donald Jack
Object Type: Letter
System: The UNT Digital Library
[Letter from Bill McCarter, Jack Davis and Nancy Reynolds to Russell Chapman, May 7, 1993] (open access)

[Letter from Bill McCarter, Jack Davis and Nancy Reynolds to Russell Chapman, May 7, 1993]

Photocopy of a letter from Bill McCarter, Jack Davis and Nancy Reynolds, North Texas Institute for Educators on the Visual Arts, to Russel Chapman, Principal of Lakewood Elementary School. In regards to Chapman's selection by the Getty Institute to represent North Texas Institute for Educators on the Visual Arts at the upcoming National Administrators Focus Group Conference and that Chapman's enthusiasm and dedication to the discipline-based art education, DBAE, program deserves recognition. The focus group meeting is an opportunity for Chapman to convene with other administrators to discuss programs such as DBAE and to present how successful DBAE is with Lakewood.
Date: May 7, 1993
Creator: Davis, Donald Jack; McCarter, William & Reynolds, Nancy
Object Type: Letter
System: The UNT Digital Library