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[News Script: Aging]

Description: Script from the WBAP-TV/NBC station in Fort Worth, Texas, relating a news story about Senator John Tower speaking to about 1500 elderly people at the Tarrant County Conference on Aging about the government being concerned about the senior citizen's life cycle.
Date: September 23, 1972, 10:00 p.m.
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections
open access

/sup 238/PuO/sub 2/ fines generation in radioisotopic heat sources

Description: Fuel aging studies were performed on the fuel form (plutonium-238 dioxide and yttrium) used in the Milliwatt Generator Radioisotopic Heat Source to determine the possibility of fuel degradation and of the resultant generation of respirable fines. In addition to long-term thermal aging of the fuel, evaluations included the effects of thermal ramping of the aged fuel to 1000/sup 0/C and of impacting thermally hot (450/sup 0/C) heat sources at 150 m/sec after thermal aging.
Date: June 23, 1983
Creator: Teaney, P. E.
Partner: UNT Libraries Government Documents Department
open access

Fatigue-crack propagation response of two nickel-base alloys in a liquid sodium environment

Description: The elevated temperature fatigue-crack propagation response of Inconel 600 and Inconel 718 was characterized within a linear-elastic fracture mechanics framework in air and low-oxygen liquid sodium environments. The crack growth rates of both nickel-base alloys tested in liquid sodium were found to be considerably lower than those obtained in air. This enhanced fatigue resistance in sodium was attributed to the very low oxygen content in the inert sodium environment. Electron fractographic exam… more
Date: January 23, 1979
Creator: Mills, W. J. & James, L. A.
Partner: UNT Libraries Government Documents Department
open access

Aging and Phase Stability of Alloy 22 Welds FY05 SUMMARY REPORT

Description: Evaluation of the fabrication processes involved in the manufacture of waste containers is important as these processes can have an effect on the metallurgical structure of an alloy. Since material properties such as strength, toughness, aging kinetics and corrosion resistance are all dependent on the microstructure, it is important that prototypes be built and evaluated for processing effects on the performance of the material. Of particular importance are welds, which have an as-cast microstr… more
Date: November 23, 2005
Creator: Torres, S G; El-Dasher, B; McGregor, M; Etien, R; Edgecumbe, T S; Gdowski, G et al.
Partner: UNT Libraries Government Documents Department
open access

Evidence for the Spectroscopic Signature of Aging in (delta)-Pu(Ga)

Description: Plutonium, because of its radioactive nature, ages from the 'inside out' by means of self-irradiation damage and thus produces nanoscale internal defects. The self-irradiation induced defects come in the form of Frenkel-type defects (vacancies and self-interstitial atoms), helium in-growth, and defect clusters. At present there are neither experimental nor theoretical models describing the changes in the electronic structure caused by the aging in Pu. This fact appears to be associated primaril… more
Date: November 23, 2005
Creator: Chung, B. W.; Schwartz, A. J.; Ebbinghaus, B. B.; Fluss, M. J.; Haslam, J. J.; Blobaum, K. M. et al.
Partner: UNT Libraries Government Documents Department
open access

Towards Understanding the Mechanism of PETN Coarsening

Description: The long-term goal is to determine the mechanism of PETN crystallization and coarsening at the solid-vapor interface and to quantify the thermodynamic and kinetic parameters that control those processes. We achieve this goal by investigating the surface evolution of synthetic PETN single crystals using in situ atomic force microscopy (AFM) at various temperatures.
Date: March 23, 2005
Creator: Qiu, R.; Overturf, G.; Gee, R.; Burnham, A.; Weeks, B. & De Yoreo, J.
Partner: UNT Libraries Government Documents Department
open access

Liguefaction Evaluations at the Savannah River Site a Case History

Description: Over the past decade, liquefaction assessments have been performed for many existing and planned critical facilities at the Department of Energy's Savannah River Site (SRS). The assessments incorporated site-specific Cyclic Resistance Ratio (CRR) and K with the use of the cone penetration test (CPT). The SRS-specific CRR and K were developed from laboratory testing of carefully collected samples. Test results show SRS soils have increased liquefaction resistance of two to three times when compa… more
Date: September 23, 2003
Creator: McHood, M.D.
Partner: UNT Libraries Government Documents Department
open access

Aging and weathering of cool roofing membranes

Description: Aging and weathering can reduce the solar reflectance of cool roofing materials. This paper summarizes laboratory measurements of the solar spectral reflectance of unweathered, weathered, and cleaned samples collected from single-ply roofing membranes at various sites across the United States. Fifteen samples were examined in each of the following six conditions: unweathered; weathered; weathered and brushed; weathered, brushed and then rinsed with water; weathered, brushed, rinsed with water, … more
Date: August 23, 2005
Creator: Akbari, Hashem; Berhe, Asmeret A.; Levinson, Ronnen; Graveline,Stanley; Foley, Kevin; Delgado, Ana H. et al.
Partner: UNT Libraries Government Documents Department
open access

CP: AN INVESTIGATION OF COEFFICIENT OF THERMAL EXPANSION, DECOMPOSITION KINETICS, AND REACTION TO VARIOUS STIMULI

Description: The properties of pentaamine (5-cyano-2H-tetrazolato-N2) cobalt (III) perchlorate (CP), which was first synthesized in 1968, continues to be of interest for predicting behavior in handling, shipping, aging, and thermal cook-off situations. We report coefficient of thermal expansion (CTE) values over four specific temperature ranges, decomposition kinetics using linear heating rates, and the reaction to three different types of stimuli: impact, spark, and friction. The CTE was measured using a T… more
Date: March 23, 2005
Creator: Weese, R. K.; Burnham, A. K. & Fontes, A. T.
Partner: UNT Libraries Government Documents Department
open access

Containment Prospectus for the PIANO Experiment

Description: PIANO is a dynamic, subcritical, zero-yield experiment intended for execution in the U1a.102C drift of the U1a complex at the Nevada Test Site (NTS) (Figure 1). The data from the PIANO experiment will be used in the Stockpile Stewardship Program to assess the aging of nuclear weapon components and to better model the long-term performance of the weapons in the enduring stockpile. The PIANO experiment is composed of one experimental package. The experimental package will have high explosive (HE)… more
Date: March 23, 2001
Creator: Burkhard, N R
Partner: UNT Libraries Government Documents Department
open access

Pattern recognition at Lawrence Livermore Laboratory

Description: Possible uses of pattern recognition techniques for solving complex scientific problems are discussed, and previous experience in using the pattern recognition computer code RECOG to solve materials problems, specifically in determining the mechanical properties of high explosives, is described. (LCL)
Date: May 23, 1975
Creator: Bender, C. F.
Partner: UNT Libraries Government Documents Department
open access

Compatibility and Outgassing Studies for Directed Stockpile Work (FY05)

Description: Compatibility and outgassing studies of non-nuclear materials were carried out in support of the W80 Life Extension Program. These studies included small-scale laboratory experiments as well as participation in Sandia's Materials Aging and Compatibility test (MAC-1). Analysis of the outgassing signature of removable epoxy foam (REF) revealed unusually high levels of volatile organic compounds in the material. REF was replaced with the polyurethane PMDI. Laboratory compatibility tests of high pr… more
Date: November 23, 2005
Creator: Alviso, C; Harvey, C & Vance, A
Partner: UNT Libraries Government Documents Department
open access

Electrical Contact Performance Degradation in Electromechanical Components

Description: Detailed materials evaluations have been performed for MC2969 Intent Stronglink switch monitor circuit parts returned from the field out of retired weapon systems. Evaluations of local contact resistance, surface chemical composition and surface roughness and wear have been determined as a function of component level contact loop resistance testing position. Several degradation mechanisms have been identified and correlated with the component level measurements. Operational degradation produces… more
Date: March 23, 1999
Creator: Peebles, D. E.; Dugger, M. T.; Neff, S. G.; Sorroche, E. H.; Robinson, J. A.; Fanska, J. et al.
Partner: UNT Libraries Government Documents Department
open access

Aging and Phase Stability of Waste Package Outer Barrier

Description: This Analysis Model Report (AMR) was prepared in accordance with the Work Direction and Planning Document, ''Aging and Phase Stability of Waste Package Outer Barrier'' (CRWMS M&O 1999a). ICN 01 of this AMR was developed following guidelines provided in TWP-MGR-MD-000004 REV 01, ''Technical Work Plan for: Integrated Management of Technical Product Input Department'' (BSC 2001, Addendum B). It takes into consideration the Enhanced Design Alternative II (EDA II), which has been selected as the… more
Date: August 23, 2001
Creator: Summers, Tammy S. Edgecumble
Partner: UNT Libraries Government Documents Department
open access

An Evaluation of Condition Monitoring Techniques for Low-Voltage Electric Cables

Description: Aging of systems and components in nuclear power plants is a well known occurrence that must be managed to ensure the continued safe operation of these plants. Much of the degradation due to aging is controlled through periodic maintenance and/or component replacement. However, there are components that do not receive periodic maintenance or monitoring once they are installed; electric cables are such a component. To provide a means of monitoring the condition of electric cables, research is on… more
Date: July 23, 2000
Creator: Lofaro, Robert J.; Grove, Edward & Soo, Peter
Partner: UNT Libraries Government Documents Department
open access

Silicon materials task of the low cost solar array project (Phase III). Effects of impurities and processing on silicon solar cells. Phase III summary and seventeenth quarterly report, Volume 2: analysis of impurity behavior

Description: The object of this phase of the program has been to investigate the effects of various processes, metal contaminants and contaminant-process interactions on the properties of silicon and on the performance of terrestrial silicon solar cells. The study encompassed topics including thermochemical (gettering) treatments, base doping concentration, base doping type (n vs. p), grain boundary-impurity interaction, non-uniformity of impurity distribution, long term effects of impurities, as well as sy… more
Date: January 23, 1980
Creator: Hopkins, R. H.; Davis, J. R.; Rohatgi, A.; Campbell, R. B.; Blais, P. D.; Rai-Choudhury, P. et al.
Partner: UNT Libraries Government Documents Department
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