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open access

Silicon drift chamber studies for the RHIC STAR experiment

Description: The two-hit resolution of a silicon drift chamber is measured using a pulsed Nd:Yag laser and a time digitizer readout. The data is analyzed by forming the covariance matrix in time samples, and transforming to a matrix in amplitude and time variation of each of the two hits. The resolution of the two-hit separation is found to be better than 25 microns with a drift field of 530 V/cm and a separation of more than 500 microns, with the resolution increasing to 50 microns as the separation nears … more
Date: February 24, 1992
Creator: Humanic, T.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The effect of the light round-trip time on the performance of an adaptive optics turbulence compensation system

Description: The propagation of a laser beam through atmospheric turbulence can, under many circumstances, be compensated to near diffraction limited levels, by use of an adaptive optics system. In the ideal case, a beacon light source is generated at the aimpoint. This light traverses through the turbulent path back to the aperture. The distribution of phase perturbations in the aperture plane is sensed, and the reverse of this phase is applied to the outgoing beam. When the turbulent path is long (i.e. a … more
Date: February 24, 1992
Creator: Stroud, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development of an experimental data base and theories for prediction of thermodynamic properties of aqueous electrolytes and nonelectrolytes of geochemical significance at supercritical temperatures and pressures

Description: This project is divided into method experimental measurements, theoretical development, and geochemical applications. We have completed experimental volumetric measurements on aqueous solutions of CO{sub 2} H{sub 2}S, CH{sub 4}, NH{sub 3} and B(OH){sub 3} at 25 to 432{degree}C and 280 and 350 bar. A vibrating tube densitometer that allows density measurements near bubble point and also measures the bubble pressure was developed and used to measure densities and bubble pressures of aqueous Co{su… more
Date: February 24, 1992
Creator: Wood, R.H.; Hnedkovsky, L.; Lin, Ching Lung (Delaware Univ., Newark, DE (United States). Dept. of Chemistry and Biochemistry) & Shock, E.L. (Washington Univ., St. Louis, MO (United States). Dept. of Earth and Planetary Sciences)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High Temperature Alkali Corrosion of Ceramics in Coal Gas

Description: The high temperature alkali corrosion kinetics of SiC have been systematically investigated from 950 to 1100[degrees]C at 0.63 vol % alkali vapor concentration. The corrosion rate in the presence of alkaliis approximately 10[sup 4] to 10[sup 5] times faster than the oxidation rate of SiC in air. The activation energy associated with the alkali corrosion is 406 kJ/mol, indicating a highly temperature-dependent reaction rate. The rate-controlling step of the overall reaction is likely to be the d… more
Date: February 24, 1992
Creator: Pickrell, G. R.; Sun, T. & Brown, J. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Interstitial embrittlement in vanadium laser welds

Description: Efficiencies of interstitial absorption during pulsed ND:YAG laser welding of vanadium were compared for nitrogen, oxygen, hydrogen, and water vapor. Influence of interstitial levels on the embrittlement of vanadium laser welds was also measured. For 1000 ppM contaminant levels in the weld atmosphere, weld hydrogen content increased 9 ppM, nitrogen content increased 190 ppM, and oxygen content increased from 500 ppM relative to baseplate levels. Welds in ultrahigh-purity argon atmospheres conta… more
Date: February 24, 1992
Creator: Strum, M.J. & Wagner, L.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Aspects of the DWPF melter significant to waste acceptance

Description: The repository program has established quality assurance requirements which are to be applied to activities and items which affect compliance with the Waste Acceptance Preliminary Specifications (WAPS). In this report, the aspects of the melter which are significant to meeting the WAPS are identified. Based on the Waste Form Compliance Plans (WCP), the melter plays a significant role in satisfying specification 1.3 (Product Consistency) by ensuring that feed material is sufficiently vitrified b… more
Date: February 24, 1992
Creator: Plodinec, M. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Interstitial embrittlement in vanadium laser welds

Description: Efficiencies of interstitial absorption during pulsed ND:YAG laser welding of vanadium were compared for nitrogen, oxygen, hydrogen, and water vapor. Influence of interstitial levels on the embrittlement of vanadium laser welds was also measured. For 1000 ppM contaminant levels in the weld atmosphere, weld hydrogen content increased 9 ppM, nitrogen content increased 190 ppM, and oxygen content increased from 500 ppM relative to baseplate levels. Welds in ultrahigh-purity argon atmospheres conta… more
Date: February 24, 1992
Creator: Strum, M. J. & Wagner, L. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The effect of the light round-trip time on the performance of an adaptive optics turbulence compensation system. Final report

Description: The propagation of a laser beam through atmospheric turbulence can, under many circumstances, be compensated to near diffraction limited levels, by use of an adaptive optics system. In the ideal case, a beacon light source is generated at the aimpoint. This light traverses through the turbulent path back to the aperture. The distribution of phase perturbations in the aperture plane is sensed, and the reverse of this phase is applied to the outgoing beam. When the turbulent path is long (i.e. a … more
Date: February 24, 1992
Creator: Stroud, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High temperature alkali corrosion of ceramics in coal gas. Quarterly progress report No. 6, December 1, 1992--February 28, 1993

Description: The high temperature alkali corrosion kinetics of SiC have been systematically investigated from 950 to 1100{degrees}C at 0.63 vol % alkali vapor concentration. The corrosion rate in the presence of alkaliis approximately 10{sup 4} to 10{sup 5} times faster than the oxidation rate of SiC in air. The activation energy associated with the alkali corrosion is 406 kJ/mol, indicating a highly temperature-dependent reaction rate. The rate-controlling step of the overall reaction is likely to be the d… more
Date: February 24, 1992
Creator: Pickrell, G. R.; Sun, T. & Brown, J. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

[Fax from William McCarter to Sheila Brown, February 24, 1992]

Description: A fax from William McCarter, co-director of North Texas Institute for Educators on the Visual Arts, to Sheila Brown, director of Prairie Visions, the Nebraska Institute. In reply to a fax from Brown to McCarter with an attachment from Mike Feduk and Braden Kuhlmen to the Satellite Educational Resources Consortium, Inc. The attachment is in regards to descriptors Feduk and Kuhlmen have provided to SERC, in regards to the teleconference between Nebraska and the North Texas Institute. McCarter's n… more
Date: February 24, 1992
Creator: McCarter, William
Item Type: Refine your search to only Letter
Partner: UNT Libraries Special Collections
open access

Aspects of the DWPF melter significant to waste acceptance

Description: The repository program has established quality assurance requirements which are to be applied to activities and items which affect compliance with the Waste Acceptance Preliminary Specifications (WAPS). In this report, the aspects of the melter which are significant to meeting the WAPS are identified. Based on the Waste Form Compliance Plans (WCP), the melter plays a significant role in satisfying specification 1.3 (Product Consistency) by ensuring that feed material is sufficiently vitrified b… more
Date: February 24, 1992
Creator: Plodinec, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Silicon drift chamber studies for the RHIC STAR experiment. Progress report, [May 1, 1991--April 30, 1992]

Description: The two-hit resolution of a silicon drift chamber is measured using a pulsed Nd:Yag laser and a time digitizer readout. The data is analyzed by forming the covariance matrix in time samples, and transforming to a matrix in amplitude and time variation of each of the two hits. The resolution of the two-hit separation is found to be better than 25 microns with a drift field of 530 V/cm and a separation of more than 500 microns, with the resolution increasing to 50 microns as the separation nears … more
Date: February 24, 1992
Creator: Humanic, T. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Development of an experimental data base and theories for prediction of thermodynamic properties of aqueous electrolytes and nonelectrolytes of geochemical significance at supercritical temperatures and pressures. Annual performance report

Description: This project is divided into method experimental measurements, theoretical development, and geochemical applications. We have completed experimental volumetric measurements on aqueous solutions of CO{sub 2} H{sub 2}S, CH{sub 4}, NH{sub 3} and B(OH){sub 3} at 25 to 432{degree}C and 280 and 350 bar. A vibrating tube densitometer that allows density measurements near bubble point and also measures the bubble pressure was developed and used to measure densities and bubble pressures of aqueous Co{su… more
Date: February 24, 1992
Creator: Wood, R. H.; Hnedkovsky, L.; Lin, Ching Lung & Shock, E. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
captions transcript

[News Clip: GM Reaction]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: February 24, 1992, 10:00 p.m.
Duration: 1 minute 27 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: EPA Lead Again!!]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: February 24, 1992, 6:00 p.m.
Duration: 42 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
captions transcript

[News Clip: Dallas Budget]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: February 24, 1992, 6:00 p.m.
Duration: 1 minute 51 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
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