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in subjects: "36 Materials Science"

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Recovery of deformed and hydrogen-charge palladium

Positron lifetime and Doppler-broadening studies made at 300 K have been used to investigate the interaction between interstitial hydrogen and lattice defects in deformed Pd. Specimens were charged with hydrogen at 300 K to levels up to 0.1%. The presence of hydrogen was found to have no effect on the recovery curves of Pd upon annealing to 400/sup 0/C. By 400/sup 0/C the values for both lifetime and Doppler-broadening for both cold worked and cold worked plus hydrogen were below the values obt… more

Date: January 1, 1982

Creator: Snead, C. L. Jr.; Lynn, K. G. & Lynch, J. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Low-Cost Solar Array Project. Progress report 14, August 1979-December 1979 and proceedings of the 14th Project Integration Meeting

Progress made by the Low-Cost Solar Array Project during the period August through November 1979, is described. Progress 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 the steps taken to integrate these efforts are detailed. A report on the Project Integration Meeting held December 5-6, 1979, including copies of the visual materials used, … more

Date: January 1, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Low cost Czochralski crystal growing technology: near term implementation of the flat plate photovoltaic cost reduction of the Low Cost Solar Array Project. Fifth quarterly progress report, April 1-June 30, 1980

During this reporting period, the primary activity has been to develop microprocessor control of the crystal growth process and to develop and demonstrate the accelerated crystal growth program. Accelerated recharging of the quartz crucible by the RF melting of polycrystalline silicon feed rods was deemphasized by JPL primarily due to the unavailability of suitable quality feed rods at an effective economical price. The development of the cold crucible program as an alternative method of crucib… more

Date: January 1, 1980

Creator: Roberts, E. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Boron reclamation

A process to recover high purity /sup 10/B enriched crystalline boron powder from a polymeric matrix was developed on a laboratory basis and ultimately scaled up to production capacity. The process is based on controlled pyrolysis of boron-filled scrap followed by an acid leach and dry sieving operation to return the powder to the required purity and particle size specifications. Typically, the recovery rate of the crystalline powder is in excess of 98.5 percent, and some of the remaining boron… more

Date: July 1, 1980

Creator: Smith, R. M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Microcrystalline silicon growth for heterojunction solar cells. Second quarterly report, 1 April 1983-30 June 1983

In this reporting period, a single source of evaporation with B mixed with highly doped Si was used instead of the co-evaporation of separate Si and B sources. The purpose was to reduce possible carbon contamination. The results of both the heterojunction or heteroface structures, however, were similar to last quarter when evaporation was used. The best Voc of the heterojunction was about 460mV and no improvement in Voc in the heteroface structure, was observed; slight Voc degradation occurred.… more

Date: January 1, 1983

Creator: Iles, P. A.; Leung, D. C. & Fang, P. H.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Sintering of polycrystalline ionic conductors:. beta. ''-Al/sub 2/O/sub 3/ and NASICON

The densification kinetics for both ..beta..''-alumina and NASICON are dramatically different. ..beta..''-Alumina sinters by a reactive liquid process whereas NASICON densifies by a solid state method. More importantly, a qualitative examination of particle and agglomerate distributions, phase composition, linear shrinkage analysis, and heating rate effects can result in a concise determination of sintering processes without recourse to more quantitative techniques. Such a s… more

Date: January 1, 1979

Creator: McEntire, B. J.; Miller, G. R. & Gordon, R. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Damage nucleation in Si during ion irradiation

Damage nucleation in single crystals of silicon during ion irradiation is investigated. Experimental results and mechanisms for damage nucleation during both room and liquid nitrogen temperature irradiation with different mass ions are discussed. It is shown that the accumulation of damage during room temperature irradiation depends on the rate of implantation. These dose rate effects are found to decrease in magnitude as the mass of the ions is increased. The significance of dose rate effects … more

Date: January 1, 1984

Creator: Holland, O.W.; Fathy, D. & Narayan, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Institutional research and development, FY 1987

The Institutional Research and Development program at Lawrence Livermore National Laboratory fosters exploratory work to advance science and technology, disciplinary research to develop innovative solutions to problems in various scientific fields, and long-term interdisciplinary research in support of defense and energy missions. This annual report describes research funded under this program for FY87. (DWL)

Date: January 1, 1987

Creator: Struble, G. L.; Lawler, G. M.; Crawford, R. B.; Kirvel, R. D.; Peck, T. M.; Prono, J. K. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Electronic band structure and optical properties of the cubic, Sc, Y and La hydride systems

Electronic band structure calculations are used to interpret the optical spectra of the cubic Sc, Y and La hydride systems. Self-consistent band calculations of ScH/sub 2/ and YH/sub 2/ were carried out. The respective joint densities of states are computed and compared to the dielectric functions determined from the optical measurements. Additional calculations were performed in which the Fermi level or band gap energies are rigidly shifted by a small energy increment. These calculations are t… more

Date: January 1, 1980

Creator: Peterman, D. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Vacuum ultraviolet electronic properties of liquids. Annual progress report, 1 November 1979-31 October 1980

Areas covered are: optical and dielectric properties of hexamethyl-phosphoric triamide; photoemission from uv irradiated liquids; photon and photoelectron mean free paths in liquids; properties of Kapton films; and uv transmission of polycyclic organic molecules. (GHT)

Date: January 1, 1980

Creator: Painter, L.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Video monitoring system for enriched uranium casting furnaces

A closed-circuit television (CCTV) system was developed to upgrade the remote-viewing capability on two oralloy (highly enriched uranium) casting furnaces in the Y-12 Plant. A silicon vidicon CCTV camera with a remotely controlled lens and infrared filtering was provided to yield a good-quality video presentation of the furnace crucible as the oralloy material is heated from 25 to 1300/sup 0/C. Existing tube-type CCTV monochrome monitors were replaced with solid-state monitors to increase the s… more

Date: March 1, 1978

Creator: Turner, P. C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Stress corrosion cracking of uranium--niobium alloys

The stress corrosion cracking behavior of U-2/sup 1///sub 4/, 4/sup 1///sub 2/, 6 and 8 wt % Nb alloys was evaluated in laboratory air and in aqueous Cl/sup -/ solutions. Thresholds for crack propagation were obtained in these environments. The data showed that Cl/sup -/ solutions are more deleterious than air environments. Tests were also conducted in pure gases to identify the species in the air responsible for cracking. These data showed the primary stress corrodent is water vapor for the mo… more

Date: March 1, 1978

Creator: Magnani, N.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Testing program for determining the mechanical properties of concrete to temperatures of 621/sup 0/C

Concrete temperatures in a Liquid Metal Fast Breeder Reactor (LMFBR) in excess of normal code limits can result from postulated large sodium spills in equipment cells. Elevated temperature concrete property data which may have application for providing a basis for the design and evaluation of such postulated accident conditions is limited. Data thus needed to be developed commensurate with LMFBR plant applications for critical physical and mechanical concrete properties under prototypic thermal… more

Date: January 1, 1980

Creator: Oland, C.B.; Naus, D.J. & Robinson, G.C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Compatibility testing of vitrified waste forms

An experimental program to evaluate candidate metals for use in the fabrication of canisters for long-term storage of vitrified radioactive wastes is described. The long-term compatibility of the candidate metal both with the contained vitrified radioactive waste and with the external environments expected in possible final storage locations will be determined. These tests involve heating combinations of waste forms and canister metals in intimate contact for up to 50,000 hr to accelerate any r… more

Date: March 6, 1978

Creator: Rankin, W.N.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Discussion: ''toughness variations during the tempering of a plain carbon martensitic steel'' by J. E. King, R. F. Smith and J. F. Knott. Retained austenite and transgranular tempered martensite embrittlement

Discussion is presented to substantiate, clarify and reinterpret some of the results of the above authors for the existence and origin of tempered martensite embrittlement (TME) in relation to retained austenite, with reference to the experimental steels worked at LBL for the past several years.

Date: June 1, 1977

Creator: Rao, B.V.N. & Thomas, G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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High temperature ceramic membrane reactors for coal liquid upgrading

In this project we intend to study a novel process concept, i.e, the use of ceramic membranes reactors in upgrading of coal derived liquids. Membrane reactors have been used in a number of catalytic reaction processes in order to overcome the limitations on conversion imposed by thermodynamic equilibrium. They have, furthermore, the inherent capability for combining reaction and separation in a single step. Thus they offer promise for improving and optimizing yield, selectivity and performance … more

Date: January 1, 1992

Creator: Tsotsis, T.T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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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(diph… more

Date: October 7, 1991

Creator: Pang, Yi.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Joining of ceramics for high performance energy systems. Mid-term progress report, August 1, 1979-March 31, 1980

The subject program is primarily an exploratory and demonstration study of the use of silicate glass-based adhesives for bonding silicon-base refractory ceramics (SiC, Si/sub 3/N/sub 4/). The projected application is 1250 to 2050/sup 0/F relaxing joint service in high-performance energy conversion systems. The five program tasks and their current status are as follows. Task 1 - Long-Term Joint Stability. Time-temperature-transformation studies of candidate glass adhesives, out to 2000 hours sim… more

Date: October 6, 1980

Creator: Smeltzer, C E & Metcalfe, A G

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Cause of pitting in beryllium

Light microscopy, bare-film radiography, secondary ion mass spectroscopy, electron microprobe and physical testing were used to examine beryllium specimens exhibiting a stratified, pitted, pattern after chemical milling. The objective was to find the cause of this pattern. Specimens were found to have voids in excess of density specification allowances. These voids are attributed, at least in part, to the sublimation of beryllium fluoride during the vacuum hot pressing operation. The origin of … more

Date: April 16, 1982

Creator: Kershaw, R. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Measurements of the dependence of damage thresholds on laser wavelength, pulse duration and film thickness

Results of three experiments will be described. We used 351-nm and 355-nm pulses with durations of 0.6, 1, 5 and 9 ns measure thresholds for a variety of anti-reflectance and high reflectance coatings. The functional form t/sup m/, with t the pulse duration, was used to scale fluence thresholds measured at 0.6 ns to those measured at 9.0 ns. Values of the coefficient m ranged from 0.10 to 0.51. The average value was 0.30. In the second experiment, we measured thresholds at 1064 nm, 527 nm and 3… more

Date: March 1, 1984

Creator: Rainer, F.; Vercimak, C.L.; Milam, D.; Carniglia, C.K. & Tuttle Hart, T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Cadmium sulfide/copper sulfide heterojunction cell research. Final report, February 26, 1979-July 15, 1980

Extensive modifications were made to the multi-source deposition apparatus. These include the installation of a larger vacuum chamber on the existing system. The new chamber provides improved inter-source shielding, an improved substrate mounting and heating system, and a vacuum interlock for introducing substrates. CdS resistivity control by both In doping and off-stoichiometric deposition has been investigated. Indium doping has been achieved both by diffusion from a pre-deposited In layer an… more

Date: June 30, 1980

Creator: Thornton, J. A. & Cornog, D. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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X-ray measurements of stresses and defects in EFG and large grained polycrystalline silicon ribbons. First quarterly report

The first model of a modified Bond goniometer has been built and tested for the precision measurement of interplanar spacings in Si-single crystals. A change in interplanar spacing ..delta..d/d approximately = to +- 10/sup -5/ can be detected which corresponds to surface stresses of the order of +- 1000 psi. A second version of the goniometer is being assembled incorporating a removable microscope for precision alignment of the Si-strip into the primary X-ray beam.

Date: January 1, 1978

Creator: Wagner, C.N.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Repair Welding of Fusion Reactor Components

Recent experimental investigations indicate that the repair welding of irradiated materials containing greater than 1 to 2.5 appm helium leads to catastrophic cracking in the heat affected zone of the weld. The high temperatures and cooling tensile stresses which occur during the welding process lead to enhanced helium bubble growth in the heat affected zone region, resulting in catastrophic cracking upon cooling. An investigation is proposed which seeks to determine the effect of stress state … more

Date: May 20, 1992

Creator: Chin, Bryan A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Pacific Northwest Laboratory Report on Fusion Energy Research, April 1977 - June 1977

The development of economic data for fusion power plants continued in a study estimating the potential impact of a shortage of materials important in fusion plant construction. In studies developing heat transfer and fluid flow design tools for fusion reactor blankets, preconceptual design studies were initiated to identify the potential design limits of water cooling in the first wall of Tokamak Next Step (TNS) concepts. In surface effects research clean gold samples were irradiated in the Uni… more

Date: July 1, 1977

Item Type: Report

Partner: UNT Libraries Government Documents Department

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