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Correction for spectral mismatch effects on the calibration of a solar cell when using a solar simulator

Description: A general expression has been derived to enable calculation of the calibration error resulting from simulator-solar AMX spectral mismatch and from reference cell-test cell spectral mismatch. The information required includes the relative spectral response of the reference cell, the relative spectral response of the cell under test, and the relative spectral irradiance of the simulator (over the spectral range defined by cell response). The spectral irradiance of the solar AMX is assumed to be known.
Date: January 15, 1981
Creator: Seaman, C.H.
Partner: UNT Libraries Government Documents Department

Critical parameters for coarse coal underground slurry haulage systems

Description: This report describes the basic parameters which directly influence the behavior of a coal slurry pipeline transportation system and determine the limitations of the system performance. The purpose of this technology assessment is to provide an identification and understanding of the critical factors which must be given consideration in the design and evaluation of such a slurry haulage system intended for use in an underground coal mine. The slurry haulage system will be utilized to satisfy the transportation requirements of conveying, in a pipeline, the coal mined by a continuous mining machine to a storage location near the mine entrance or to a coal preparation plant located on the surface. Coal-water slurries, particularly those consisting of homogeneous suspensions of small particles, frequently behave as non-Newtonian, Bingham-plastic fluids. For successful operation, slurry transport systems should be designed to operate in the turbulent flow regime and at a flow rate at least 30% greater than the deposition velocity. The deposition velocity is defined as the slurry flow rate at which the solid particles tend to settle in the pipe. Due to the importance of accurately determining the deposition velocity and the uncertainties of current methods for predicting the deposition velocity of coarse particle slurries, it is recommended that experimental efforts be performed as a part of the system design. The capacity of the haulage system should be compatible with the mine's projected coal output in order to avoid operational delays and the necessity for in-mine coal storage. The slurry pumps must generate sufficient discharge pressure to overcome the resultant friction losses in horizontal and vertical pipe sections and to satisfy the slurry hoisting requirements.
Date: February 15, 1981
Creator: Maynard, D.P.
Partner: UNT Libraries Government Documents Department

Electric and hybrid vehicles charge efficiency tests of ESB EV-106 lead-acid batteries

Description: Charge efficiencies were determined for ESB EV-106 lead-acid batteries by measurements made under widely differing conditions of temperature, charge procedure, and battery age. The measurements were used to optimize charge procedures and to evaluate the concept of a modified, coulometric state-of-charge indicator. Charge efficiency determinations were made by measuring gassing rates and oxygen fractions. A novel, positive displacement gas flow meter which proved to be both simple and highly accurate is described and illustrated.
Date: January 15, 1981
Creator: Rowlette, J.J.
Partner: UNT Libraries Government Documents Department

Office of Nuclear Waste Isolation: HEDL stabilizer materials program, October-December quarterly report

Description: The objective of the Spent Fuel Stabilizer Materials Program is to identify, test, select, and qualify stabilizer materials for use in the design of spent fuel waste packages. Emphasis is placed on the selection of stabilizer materials with minimal interactions. The preliminary screening of candidate spent fuel stabilizer materials was completed and reported to the Office of Nuclear Waste Isolation in November 1980. Based on criteria set for thermally induced stresses, material cost, and material availability, an initial list of potential stabilizers was reduced to 34 that are recommended for additional screening tests. The spent fuel stabilizer temperature limit test was completed during this report period. Tests were conducted to establish a conservative temperature limit for spent light water reactor (LWR) fuel during the stabilizer emplacement process. Melting of metals and metal alloys, fusing of glass stabilizers,or other possible emplacement processes may require elevation of the spent fuel temperature above levels desirable for maintaining fuel rod integrity (intact cladding) or reasonable inter-rod spacing for stabilizer flow. This test was conducted to establish the temperature below which these concerns would not exist. Stabilizers that require emplacement process temperatures above the limit will be eliminated from the screening program.
Date: December 15, 1981
Creator: Fish, R.L. & Cash, R.J.
Partner: UNT Libraries Government Documents Department

Moving baseline for evaluation of advanced coal-extraction systems

Description: This document reports results from the initial effort to establish baseline economic performance comparators for a program whose intent is to define, develop, and demonstrate advanced systems suitable for coal resource extraction beyond the year 2000. Systems used in this study were selected from contemporary coal mining technology and from conservative conjectures of year 2000 technology. The analysis was also based on a seam thickness of 6 ft. Therefore, the results are specific to the study systems and the selected seam thickness. To be more beneficial to the program, the effort should be extended to other seam thicknesses. This document is one of a series which describe systems level requirements for advanced underground coal mining equipment. Five areas of performance are discussed: production cost, miner safety, miner health, environmental impact, and recovery efficiency. The projections for cost and production capability comprise a so-called moving baseline which will be used to assess compliance with the systems requirement for production cost. Separate projections were prepared for room and pillar, longwall, and shortwall technology all operating under comparable sets of mining conditions. This work is part of an effort to define and develop innovative coal extraction systems suitable for the significant resources remaining in the year 2000.
Date: April 15, 1981
Creator: Bickerton, C.R. & Westerfield, M.D.
Partner: UNT Libraries Government Documents Department

Performance of a 100-kV, 78-kJ electric-gun system

Description: A new electric gun system was constructed for use in high-pressure EOS studies. The system is powered by a 100 kV, 15.6 ..mu..F capacitor bank. At 100 kV charging voltage the system inductance is 23 nH. This system has driven 0.3 mm-thick Kapton projectiles to > 20 km/s and 0.3 mm Kapton/30 ..mu..m Ta projectiles to approx. 10 km/s. Projectile velocity is modeled phenomenlogically by an electrical Gurney model.
Date: June 15, 1981
Creator: Chau, H.; Dittbenner, G.; Mikkelsen, K.; Weingart, R.; Froeschner, K. & Lee, R.
Partner: UNT Libraries Government Documents Department

[News Clip: "Gallipoli"]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: October 15, 1981, 5:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Investigation of the hydrogenation of SiCl/sub 4/. Final report, March 31, 1979-April 1, 1981

Description: A two-year research and development program was initiated in April of 1979 to study the hydrochlorination of silicon tetrachloride and metallurgical grade (m.g.) silicon metal to trichlorosilane, 3 SiCl/sub 4/ + 2H/sub 2/ + Si in equilibrium 4 SiHCl/sub 3/. A laboratory scale pressure reactor was constructed to study this reaction at pressures up to 500 psig. Reaction kinetic measurements were carried out as a function of reactor pressure, reaction temperature and H/sub 2//SiCl/sub 4/ feed ratio. Based on the reaction kinetic data, the hydrochlorination of SiCl/sub 4/ and m.g. silicon metal is found to be an efficient process to produce SiHCl/sub 3/ in good conversions and in high yields. Copper is an effective catalyst. Results of a corrosion study show that conventional nickel-chromium alloys are suitable material of construction for the hydrochlorination reactor. The hydrochlorination reaction is relatively insensitive to external process parameters such as silicon particle size distribution and the impurities in the m.g. silicon metal.
Date: April 15, 1981
Creator: Mui, J. Y.P. & Seyferth, D.
Partner: UNT Libraries Government Documents Department

Absorption spectrophotometric characterization of Sm(II), Sm(III), and Sm(II/III) bromides and Sm(III) oxybromide in the solid state

Description: Absorption spectra obtained from SmBr/sub 3/, SmBr/sub 2/, and Sm0Br were used in identifying the samarium species in several mixed-valence Sm(II/III) compounds produced by H/sub 2/ reduction of SmBr/sub 3/. The nature of the absorption of Sm0Br made it possible to detect even traces of Sm0Br in the Sm bromides.
Date: June 15, 1981
Creator: Wood, A.B.; Young, J.P.; Peterson, J.R. & Haschke, J.M.
Partner: UNT Libraries Government Documents Department

Even-parity quartet autodetaching states of He/sup -/

Description: The total photodetachment cross section of the metastable, (1s2s2p) /sup 4/P/sup 0/ state of He/sup -/ has been recently measured at several wavelengths between 10 ..mu.. and 308 nm. As part of these calculations, the even parity, quartet, autodetaching states of He/sup -/ which are optically connected to the metastable /sup 4/P/sup 0/ state and which are associated with the n = 2 and n = 3 states of He were studied. In both the photodetachment and electron scattering calculations, extensive configuration interaction (CI) wavefunctions were used to describe the He target states, the He/sup -/ resonance states and the photodetachment continua. The Stieltjes moment-theory technique was used to extract the partial photodetachment cross sections from the discrete representations of the electron scattering continua. The use of the Stieltjes technique allowed the inclusion of both channel-channel coupling and fully correlated He /sup 3/S and /sup 3/P/sup 0/ wavefunctions in the calculations. Results are presented and discussed. (WHK)
Date: July 15, 1981
Creator: Hazi, A.U.
Partner: UNT Libraries Government Documents Department

Occurrence and use of complex resonances (poles in scattering and radiation problems)

Description: In a wide variety of physics problems, especially those which involve wave phenomena such as in electromagnetics and acoustics, a behavior results that can be described by systems of linear (partial) differential equations. Solutions to such problems often can be expressed simply in the form of an exponential series. Some specific background material for this approach is discussed, and a variety of example applications is summarized. (WHK)
Date: December 15, 1981
Creator: Miller, E.K.
Partner: UNT Libraries Government Documents Department

Usng subjective percentiles and test data for estimating fragility functions

Description: Fragility functions are cumulative distribution functions (cdfs) of strengths at failure. They are needed for reliability analyses of systems such as power generation and transmission systems. Subjective opinions supplement sparse test data for estimating fragility functions. Often the opinions are opinions on the percentiles of the fragility function. Subjective percentiles are likely to be less biased than opinions on parameters of cdfs. Solutions to several problems in the estimation of fragility functions are found for subjective percentiles and test data. How subjective percentiles should be used to estimate subjective fragility functions, how subjective percentiles should be combined with test data, how fragility functions for several failure modes should be combined into a composite fragility function, and how inherent randomness and uncertainty due to lack of knowledge should be represented are considered. Subjective percentiles are treated as independent estimates of percentiles. The following are derived: least-squares parameter estimators for normal and lognormal cdfs, based on subjective percentiles (the method is applicable to any invertible cdf); a composite fragility function for combining several failure modes; estimators of variation within and between groups of experts for nonidentically distributed subjective percentiles; weighted least-squares estimators when subjective percentiles have higher variation at higher percents; and weighted least-squares and Bayes parameter estimators based on combining subjective percentiles and test data. 4 figures, 2 tables.
Date: January 15, 1981
Creator: George, L.L. & Mensing, R.W.
Partner: UNT Libraries Government Documents Department

[News Clip: Insulation]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: September 15, 1981, 12:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Radiation and transmutation effects relevant to solid nuclear waste forms

Description: Radiation effects in insulating solids are discussed in a general way as an introduction to the quite sparse published work on radiation effects in candidate nuclear waste forms other than glasses. Likely effects of transmutation in crystals and the chemical mitigation strategy are discussed. It seems probable that radiation effects in solidified HLW will not be serious if the actinides can be wholly incorporated in such radiation-resistant phases as monazite or uraninite.
Date: March 15, 1981
Creator: Vance, E.R.; Roy, R. & Pillay, K.K.S.
Partner: UNT Libraries Government Documents Department

[News Clip: Chet Flippo]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: April 15, 1981, 5:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

[News Clip: Evans riot]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: June 15, 1981, 6:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections