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Evaluation of selected chemical processes for production of low-cost silicon. Phase III. Eighteenth quarterly progress report, January 1-March 31, 1980

Description: Progress during this report period was marked by the initial operation of the Process Development Unit at about 50% of design capacity with indications that many aspects of the facility operated satisfactorily. However, a downstream constriction, the cause of which is being isolated, led to termination of the run after one-half hour of operation. In the light of observations made during earlier start-up efforts, several modifications of equipment and technique were made for improved operation. Vacuum outgassing experiments (850 to 1100/sup 0/C, 1 to 256 h) were carried out on miniplant-produced granules containing 360 and 3900 ppMw of zinc in the deposited silicon. Treatment of the data so that it can be extrapolated to the expected product of the Experimental Process System Development Unit awaits development of an appropriate model.
Date: May 15, 1980
Creator: Blocher, J.M. Jr. & Browning, M.F.
Partner: UNT Libraries Government Documents Department

Low-Cost Solar Array Project. Task I. Silicon material: investigation of the hydrogenation of SiCl/sub 4/. Fourth quarterly report

Description: 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 and H/sub 2//SiCl/sub 4/ feed ratio. 3 SiCl/sub 4/ + S H/sub 2/ + Si reversible 4 SiHCl/sub 3/. The same reaction has been studied in the presence of a copper catalyst. The presence of copper approximately doubles the reaction rates. A cement-type copper supplied by Union Carbide was evaluated at 5 wt % loading. After an induction period of about 22 hours, it began to show significant catalytic activity. Reaction kinetic measurements were then made as a function of reaction temperature (450/sup 0/, 500/sup 0/C), reactor pressure (300, 500 psig) and H/sub 2//SiCl/sub 4/ feed ratio (1.0 and 2.8). Another copper compound (CuCl) also was evaluated as a catalyst at 5 wt %. With CuCl, there was no induction period and full catalytic activity was observed soon after the reactor was brought to reaction conditions. Both cement copper and CuCl show about the same catalytic activity by doubling the reaction rate. Results of the copper studies provide some experimental evidence on the mechanism of the hydrochlorination reaction and on the nature of the copper catalyst.
Date: April 15, 1980
Creator: Mui, J.Y.P. & Seyferth, D.
Partner: UNT Libraries Government Documents Department

Development of tailored ceramics for geologic storage of nuclear wastes. Quarterly progress report, October 1, 1979-December 31, 1979

Description: Tailored ceramics are crystalline assemblages made by high-temperature and pressure consolidation of a nuclear waste with selected additives. The multitask program includes waste form development and characterizations, and process and equipment development. (DLC)
Date: February 15, 1980
Partner: UNT Libraries Government Documents Department

What masses for Cepheids

Description: To understand the evolution of giant stars, it is important to pin down the masses for Cepheids. The 7- to 10-day bump Cepheids imply lower than evolutionary mass (60%). Recent theoretical work, though, indicates that for Cepheids with periods of 15 to 16 days, the best understanding of the light curves results from using evolutionary masses.
Date: September 15, 1980
Creator: Davis, C.G.
Partner: UNT Libraries Government Documents Department

Picosecond x-ray measurements from 100 eV to 30 keV

Description: Picosecond x-ray measurements relevant to the Livermore Laser Fusion Program are reviewed. Resolved to 15 picoseconds, streak camera detection capabilities extend from 100 eV to higher than 30 keV, with synchronous capabilities in the visible, near infrared, and ultraviolet. Capabilities include automated data retrieval using charge coupled devices (CCD's), absolute x-ray intensity levels, novel cathodes, x-ray mirror/reflector combinations, and a variety of x-ray imaging devices.
Date: October 15, 1980
Creator: Attwood, D.T.; Kauffman, R.L. & Stradling, G.L.
Partner: UNT Libraries Government Documents Department

Physical and chemical characteristics of candidate wastes for tailored ceramics

Description: Tailored Ceramics offer a potential alternative to glass as an immobilization form for nuclear waste disposal. The form is applicable to the wide variety of existing wastes and may be tailored to suit the diverse environments being considered as disposal sites. Consideration of any waste product form, however, require extensive knowledge of the waste to be incorporated. A varity of waste types are under consideration for incorporation into a Tailored Ceramic form. This report integrates and summarizes chemical and physical characteristics of the candidate wastes. Included here are data on Savannah River Purex Process waste; Hanford bismuth phosphate, uranium recovery, redox, Purex, evaporator and residual liquid wastes; Idaho Falls calcine; Nuclear Fuel Services Purex and Thorex wastes and miscellaneous waste including estimated waste stream compositions produced by possible future commercial fuel reprocessing.
Date: December 15, 1980
Creator: Mitchell, M.E.
Partner: UNT Libraries Government Documents Department

Development of tailored ceramics for geologic storage of nuclear wastes. Quarterly progress report, January 1-March 31, 1980

Description: In the second quarter of activities on developing Tailored Ceramic waste forms for SRP waste compositions, emphasis was on the chemistry controlling the incorporation of the waste elements into the crystalline phases of the high-alumina content ceramic and the major factors affecting the consolidation process. Research on the design and synthesis of oxide and phosphate ceramic waste forms has continued with emphasis on fluorite-structure oxides and on rare earth phosphates with the monazite structure. Dissolution studies to date indicate that monazite is very stable.
Date: May 15, 1980
Partner: UNT Libraries Government Documents Department

Basic studies of atomic dynamics. Progress report, October 1, 1979-September 30, 1980. [Univ. of Chicago]

Description: Potential ridges, now identified as the locus of breakdown of approximate separability of coordinates, require a special physico-mathematical treatment the initial phase of which has now been completed. The role of a potential ridge in separating the pair of exit channels of lower-energy two-electron excitations is circumscribed and hence accessible to numerical calculations; it has thus been studied in some detail for earth-alkaline-like configurations and for He/sup -/. Quantum defect theory approaches have been extended to molecular predissociation and to the study of Stark effect wave-functions; these extensions have now proved so far from the origins of the approach that a new name and description would be more appropriate.
Date: September 15, 1980
Creator: Fano, U.
Partner: UNT Libraries Government Documents Department

BNL neutral beam development group. Progress report, FY 1979

Description: The objective of the BNL Neutral Beam Program is to develop a 250 keV neutral beam system suitable for heating experiments in toroidal or mirror plasma devices. The system will be based on acceleration and neutralization of negative hydrogen ions produced in and directly extracted from a source. The objective of source studies is to develop a unit delivering 10 A of negative ion currents in pulses of 1 s duration or longer, operating with extracted current densities of at least 0.5 A/cm/sup 2/ and having acceptable power and gas efficiencies and good beam optics. The 250 keV accelerator development work covers different structures, including those separated from the source by a bending magnet or a beam transfer system. During FY 1979 substantial progress was achieved toward the objectives of the program; in the same period the BNL program was reviewed by a panel, resulting in suggestions for a better orientation toward prospective users' requirements and in establishment of contacts with Princeton Plasma Physics Laboratory (TFTR Project) and Lawrence Berkeley and Livermore Laboratories (MFTF Project). A cooperative effort with Westinghouse was initiated in the second half of FY 1979 in order to utilize industrial facilities and expertise.
Date: January 15, 1980
Creator: Prelec, K. & Sluyters, T.
Partner: UNT Libraries Government Documents Department

LLL calibration and standards facility

Description: The capabilities of Lawrence Livermore Laboratory's Calibration and Standards Facility are delineated. The facility's ability to provide radiation fields and measurements for a variety of radiation safety applications and the available radiation measurement equipment are described. The need for national laboratory calibration labs to maintain traceability to a national standard are discussed as well as the areas where improved standards and standardization techniques are needed.
Date: April 15, 1980
Creator: Campbell, G.W. & Elliott, J.H.
Partner: UNT Libraries Government Documents Department

X-ray diffraction studies of binary plutonium. Uranium alloys: an interim report

Description: This report describes x-ray diffraction studies of Pu-U alloys carried on at LLNL in 1972. These studies were part of a larger project to understand the 2-phase, banded microstructures observed in Pu-15 wt% U alloys by Riefenberg and Ellinger. This work has produced relatively high-quality diffraction patterns for both components of the banded structures, but computer indexing of these patterns did not produce acceptable solutions for either the zeta-phase or the second component of the banded structures. The effect of uranium on ..cap alpha..-Pu's lattice parameters is determined, and the data for the effect of uranium on ..beta..-Pu's lattice parameters are extended.
Date: December 15, 1980
Creator: Wallace, P.L. & Harvey, M.R.
Partner: UNT Libraries Government Documents Department

Utilization of coal associated minerals. Quarterly report No. 10, January 1-March 31, 1980

Description: In the preceding quarterly report, it was reported that while sampling the Solvent Refined Coal II (SRC II) pilot plant at Fort Lewis, Washington, the plant went down and vacuum bottoms waste material representing the minerals flow at the last steady state condition were obtained. This plant has been sampled again and samples of the incoming feed coal, sized coal and vacuum bottoms waste material were obtained. As part of our effort to trace the same mineral suite through mining, preparation and conversion, new samples of feed coal, cleaned coal and refuse were obtained from the District 4 commercial preparation plant. This preparation plant supplies coal to the SRC II pilot plant at Fort Lewis, Washington. A study of the thermal insulating properties of fired flyash based structural materials was completed and is included.
Date: July 15, 1980
Creator: Slonaker, J. F.; Buttermore, W. H.; Carlisle, J. A.; Durham, D. L.; Muter, R. B. & Alderman, J. K.
Partner: UNT Libraries Government Documents Department

Project for laboratory study for removal of organic sulfur from coal. Quarterly technical progress report

Description: The Gravimelt Process was extended to the desulfurization of ordinary mine-cleaned Kentucky No. 11 coal obtained from the Tennessee Valley Authority. Eight process runs were made resulting in reduction of the sulfur content from a starting 2.7 lbs S/10/sup 6/ Btu to a mean of 0.475 lbs S/10/sup 6/ Btu, (0.95 lbs SO/sub 2//10/sup 6/ Btu) for an average 82% sulfur reduction. The effect of utilization of molten sodium hydroxide alone vs molten mixed potassium and sodium hydroxide was investigated for this coal; sulfur reduction averaged 84% for the mixed melt and 78% for the use of sodium hydroxide alone. A double extraction with sodium hydroxide resulted in a reduction in total sulfur to 0.3 lbs S/10/sup 6/ Btu which is an 89% reduction. In a series of experiments, the melt was reused three times on fresh samples of coal, always giving the same amount of sulfur reduction. Extraction of the desulfurized Kentucky No. 11 coals with an additional dilute sulfuric acid wash reduced the ash content of the coal from 7.9% to a level of 0.3%, thus providing a solid hydrocarbon fuel similar in both ash and sulfur content to a medium grade fuel oil. Multiple experimentation on high ash Kentucky No. 9 sink coal demonstrated that water washing alone reduces the sum of sodium and potassium retained on the coal the the level of the starting input coal or to a level of approximately 1% total alkali metals. Thus, retention of alkali metals by Gravimelt treated coal will not be a problem.
Date: October 15, 1980
Partner: UNT Libraries Government Documents Department

Saturation of hot CO/sub 2/ at 10. 6. mu. m

Description: Saturation of the short laser pulse transmission of hot CO/sub 2/ has been studied experimentally and theoretically. Pure CO/sub 2/ at 200 torr and 400 +- 3/sup 0/C was contained in a special temperature-controlled 118 cm absorption cell. The cell's energy transmission was measured as a function of the incident pulse's fluence. The incident pulses' wavelengths were either at the P18 or P20 lines of the 10.6 ..mu..m band, and their temporal shape (FWHM of 1.6 ns) was kept fixed as the fluence was changed. The data showed that the absorption of hot CO/sub 2/ saturated differently at the two wavelengths, with the P20 transition being the harder to saturate.
Date: December 15, 1980
Creator: Goldstein, J.C.; Czuchlewski, S.J. & Nowak, A.V.
Partner: UNT Libraries Government Documents Department