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in subjects: "Thermal Cycling"

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Protective coatings and sealants for solar applications

An aging study has been completed which evaluated a number of polymeric materials for potential use as (1) protective coatings for back surfaces of mirrors and (2) solar heliostat edge seals. These investigations were conducted in an artificial weathering chamber that accelerated thermal cycling. The primary mirror failure mode was observed to be silver corrosion resulting from moisture exposure. To increase mirror longevity in current heliostat designs, intimate bonding at all the composite in… more

Date: September 1, 1980

Creator: Wischmann, K. B. & Gonzales, M. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Corrosion problems in Ti/KC1O/sub 4/ loaded devices when subjected to humid environments

A piston motor/igniter loaded with a Ti/KClO/sub 4/ pyrotechnic and sealed with a silicone adhesive exhibited serious corrosion problems during aging. Five 24-hour thermal cycles between room temperature and 71/sup 0/C at 90% relative humidity resulted in extensive surface corrosion of the Kovar pins and severe stress corrosion cracking of the Kovar pins in the vicinity of the bridgewire weld. No corrosion or cracking of the Nichrome bridgewire was observed. Similar results were observed after … more

Date: January 1, 1980

Creator: Massis, T. M.; Healey, J. T.; Huskisson, D. H. & Perkins, W. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Geothermal drilling problems and their impact on cost

Historical data are presented that demonstrate the significance of unexpected problems. In extreme cases, trouble costs are the largest component of well costs or severe troubles can lead to abandonment of a hole. Drilling experiences from US geothermal areas are used to analyze the frequency and severity of various problems. In addition, average trouble costs are estimated based on this analysis and the relationship between trouble and depth is discussed. The most frequent drilling and complet… more

Date: January 1, 1982

Creator: Carson, C. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effect of Au on the reliability of fine pitch surface mount solder joints

The effect of Au on the reliability of 0.65 mm pitch surface mount solder joints between plastic quad flat packs and Cu-Ni-Au FR-4 printed circuit boards was investigated. Cu-Ni-Au is a desirable printed circuit board finish for multi-chip modules or printed circuit boards that would otherwise require a selective Au finish, for example for edge connectors or wire bondable parts. However, Au is known to embrittle solder when it is present in sufficiently high concentrations, creating a concern t… more

Date: May 1, 1991

Creator: Glazer, J. (Hewlett-Packard Co., Palo Alto, CA (United States)); Kramer, P. & Morris, J.W. Jr. (Lawrence Berkeley Lab., CA (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Mechanical properties of TATB/Kel-F 800. Period covered: July--September 1975

No Description Available.

Date: January 1, 1975

Creator: Johnson, H.D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Photovoltaic module electrical termination design requirement study

Motorola Inc., in conjunction with ITT Cannon, has conducted a study to develop information to facilitate the selection of existing, commercial, electrical termination hardware for photovoltaic modules and arrays. This volume of the report contains the executive summary. Module and array design parameters were investigated and recommendations were developed for use in surveying, evaluating, and comparing electrical termination hardware. Electrical termination selection criteria factors were dev… more

Date: July 1, 1980

Creator: Mosna, F.J. Jr. & Donlinger, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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High-flux first-wall design for a small reversed-field pinch reactor

To achieve the goal of a commercially economical fusion power reactor, small physical size and high power density should be combined with simplicity (minimized use of high-technology systems). The Reversed-Field Pinch (RFP) is a magnetic confinement device that promises to meet these requirements with power densities comparable to those in existing fission power plants. To establish feasibility of such an RFP reactor, a practical design for a first wall capable of withstanding high levels of cy… more

Date: January 1, 1982

Creator: Cort, G. E.; Graham, A. L. & Christensen, K. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Precision programmable bipolar V/f instrumentation module

A precision bipolar voltage-to-frequency converter, which is computer-programmable from a digital interface, has been produced. Utilizing NIM packaging, the 1 MHz V/f has sixteen ranges and may be operated from panel controls as well as remotely programmed. Intended for use in magnetic measurements, good performance and versatility suggest wider application. The instrument is described and the circuit design is discussed in detail. Tests of the first unit are discussed and instrument specificat… more

Date: October 1, 1981

Creator: Hearn, W. E.; Green, M. I.; Nelson, D. H. & Rondeau, D. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Failure of sheathed thermocouples due to thermal cycling

Open circuit failures (up to 100%) in small-diameter thermocouples used in electrically heated nuclear fuel rod simulator prototypes during thermal cycling tests were investigated to determine the cause(s) of the failures. The experiments conducted to determine the relative effects of differential thermal expansion, wire size, grain size, and manufacturing technology are described. It was concluded that the large grain size and embrittlement which result from certain common manufacturing anneal… more

Date: March 1, 1982

Creator: Anderson, R.L. & Ludwig, R.L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Interconnect fatigue design for terrestrial photovoltaic modules

Fatigue of solar cell electrical interconnects due to thermal cycling has historically been a major failure mechanism in photovoltaic arrays; the results of a comprehensive investigation of interconnect fatigue that has led to the definition of useful reliability-design and life-prediction algorithms are presented. Experimental data gathered in this study indicate that the classical strain-cycle (fatigue) curve for the interconnect material is a good model of mean interconnect fatigue performan… more

Date: March 1, 1982

Creator: Mon, G. R.; Moore, D. M. & Ross, R. G., Jr.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Exposure testing of solar absorber surfaces

The Los Alamos National Laboratory has been involved in supporting, monitoring and conducting exposure testing of solar materials for approximately ten years. The Laboratory has provided technical monitoring of the IITRI, DSET, Lockheed, and Berry contracts and has operated the Los Alamos exposure Facility for over five years. This report will outline some of the past exposure testing, the testing still in progress, and describe some of the major findings. While this report will primarily empha… more

Date: January 1, 1986

Creator: Moore, S.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Thermoelectric materials evaluation program. Technical summary report

Research progress on the thermoelectric materials evaluation program is reported covering the period January 1, 1976 to September 30, 1978. Topical reports are presented on (1) hot and cold end ..delta..T's, (2) hardware mobility, (3) p-leg sublimation suppression, (4) thermodynamic stability of p-legs, (5) n-leg material process improvements to reduce extraneous resistance, (6) n-leg cracking, (7) dynamic evaluation of converter, and (8) data base and degradation modes. Twenty attachments are … more

Date: April 1979

Creator: Hinderman, J.D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Phase 2 of the array automated assembly task for the low cost silicon solar array project. Fifth quarterly report

This program focuses attention on one key step of a proposed process sequence for mass production of inexpensive silicon solar arrays for terrestrial use. The process step of concern is the metallization of the solar cell. Solarex has proposed that the metallization be accomplished by a single electroless plating of nickel followed by a dip in molten solder, and Solarex manufactures solar cells using this procedure. ing, cleaning and annealing. Motorola has recommended a process which includes … more

Date: January 1, 1980

Creator: Petersen, R. C. & Anderson, J. R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Advanced photovoltaic-trough development

The scope of the work on photvoltaic troughs includes analytical studies, hardware development, and component testing. Various aspects of the system have been optimized and improvements have been realized, particularly in the receiver and reflecting surface designs. An empirical system performance model has been developed that closely agrees with measured system performance. This in-depth study of single-axis reflecting linear focus photovoltaic concentrators will be very beneficial in the deve… more

Date: April 1, 1982

Creator: Spencer, R.; Yasuda, K. & Merson, B.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Thermophysical behavior of St. Peter sandstone: application to compressed air energy storage in an aquifer

The long-term stability of a sandstone reservoir is of primary importance to the success of compressed air energy storage (CAES) in aquifers. The purpose of this study was to: develop experimental techniques for the operation of the CAES Porous Media Flow Loop (PMFL), an apparatus designed to study the stability of porous media in subsurface geologic environments, conduct experiments in the PMFL designed to determine the effects of temperature, stress, and humidity on the stability of candidate… more

Date: December 1, 1983

Creator: Erikson, R.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development of a freeze-tolerant solar water heater using crosslinked polyethylene as a material of construction. Final report, June 18, 1976--October 1, 1977

The feasibility of building a freeze-tolerant absorber for a solar water heater out of carbon-black-reinforced crosslinked polyethylene has been explored. Ten-foot tube specimens made from various crosslinked polyethylene formulations were filled with water at various pressures, and then placed into a deep freeze, then thawed and frozen again for 100 freeze-thaw cycles, or until the tube specimen failed. Tube diameters were measured before and after each freezing to determine how much distentio… more

Date: January 1, 1978

Creator: Bradley, J.M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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High temperature molten carbonate fuel cells

Progress is reported on four tasks: (1) component development, (2) cell testing, (3) stack design and development, and (4) modeling and systems analysis. A hydrogen sintering furnace capable of producing 0.5 sq meter electrodes was installed and operating procedures are being established. To develop stabilized anode structures, a fine particle nickel-cobalt alloy powder was prepared from their hydroxide mixture through the steps of co-precipitation, spray-drying and reduction. Electrodes have b… more

Date: February 1, 1978

Creator: Baker, B.; Burns, D.; Dharia, D.; Herscovici, C.; Kinnibrugh, D.; Paetsch, L. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Photovoltaic module electrical termination design requirement study. Final report

Motorola Inc., in conjunction with ITT Cannon, has conducted a study to develop information to facilitate the selection of existing, commercial, electrical termination hardware for photovoltaic modules and arrays. Details of the study are presented in this volume. Module and array design parameters were investigated and recommendations were developed for use in surveying, evaluating, and comparing electrical termination hardware. Electrical termination selection criteria factors were developed … more

Date: July 1, 1980

Creator: Mosna, F.J. Jr. & Donlinger, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Reentry thermal testing of a general purpose heat source fueled clad

A General Purpose Heat Source (GPHS) module was exposed to heat treatments simulating an isothermal prelaunch condition, followed by thermal pulses corresponding to atmospheric reentry. Helium release rates were determined during each heating and modeled after simple diffusion theory. Following the tests, the module was examined metallurgically with no evidence of swelling of the cladding nor degradation of the fuel.

Date: March 1, 1982

Creator: Peterson, D. E. & Frantz, C. E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Heat and mass transfer considerations in advanced heat pump systems

Advanced heat-pump cycles are being investigated for various applications. However, the working media and associated thermal design aspects require new concepts for maintaining high thermal effectiveness and phase equilibrium for achieving maximum possible thermodynamic advantages. In the present study, the heat- and mass-transfer processes in two heat-pump systems -- those based on absorption processes, and those using refrigerant mixtures -- are analyzed. The major technical barriers for achi… more

Date: January 1, 1992

Creator: Panchal, C.B. & Bell, K.J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Initial testing of coated limiters in ISX-B

Low-Z coatings on graphite substrates have been developed for testing as limiters in the Impurity Study Experiment (ISX-B) tokamak. Laboratory and tokamak testings have been accomplished. The laboratory tests included thermal shock experiments by means of pulsed e-beam irradiation, arcing experiments, and hydrogen and xenon ion erosion experiments. The tokamak testing consisted of ohmically heated plasma exposures with energy depositions up to 10 kJ/discharge on the limiters. The coatings, appl… more

Date: January 1, 1980

Creator: Langley, R. A.; Emerson, L. C.; Whitley, J. B. & Mullendore, A. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Thumb tack physical model evaluation of polystyrene bead foam as an encapsulant for electronic packages

A physical model in the shape of a thumb tack is used to measure forces on electronic component lead wires when soldered into printed wiring boards. Encapsulation of electronic packages in polystyrene bead foam of 0.2, 0.3, 0.4, 0.5, and 0.6 g/cm/sup 3/ densities was evaluated. No solder joint damage was seen. Crushing pressures on metal transistors also were safe for all densities. Experimental data agreed well with theoretical calculations based on the concept of constrained thermal expansion. more

Date: March 1, 1980

Creator: Fossey, D. J. & Swanson, G. D.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Progress report 13 for April 1979-August 1979 and proceedings of the 13th project integration meeting

This report describes progress made by the Low-Cost Solar Array Project during the period April through August 1979. It includes reports on project analysis and integration; technology development in silicon material, large-area sheet silicon, and encapsulation; production process and equipment development; engineering and operations, and a discussion of the steps taken to integrate these efforts. It includes a report on, and copies of viewgraphs presented at the Project Integration Meeting hel… more

Date: January 1, 1979

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Improved alkaline hydrogen/air fuel cells for transportation applications

Considerable progress has been made in the last few years on improvement of alkaline air electrodes for air depolarized chlor-alkali cells. Some of these electrodes from Union Carbide Corporation have been evaluated at Brookhaven National Laboratory in alkaline hydrogen/air fuel cells. In initial tests with 289 cm/sup 2/ electrodes, power densities of 100 mW/cm/sup 2/ were obtained at 0.65 V. This compares with power densities of 27 mW/cm/sup 2/ obtained by Kordesch in his vehicle fuel cell in … more

Date: January 1, 1980

Creator: McBreen, J; Kissel, G; Kordesch, K V; Kulesa, F; Taylor, E J; Gannon, E et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department