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The ACP (Advanced Computer Program) Branch bus and real-time applications of the ACP multiprocessor system

Description: The ACP Branchbus, a high speed differential bus for data movement in multiprocessing and data acquisition environments, is described. This bus was designed as the central bus in the ACP multiprocessing system. In its full implementation with 16 branches and a bus switch, it will handle data rates of 160 MByte/sec and allow reliable data transmission over inter rack distances. We also summarize applications of the ACP system in experimental data acquisition, triggering and monitoring, with special attention paid to FASTBUS environments.
Date: May 8, 1987
Creator: Hance, R.; Areti, H.; Atac, R.; Biel, J.; Cook, A.; Fischler, M. et al.

Adiabatic supernova expansion into the circumstellar medium

Description: We perform one dimensional numerical simulations with a Lagrangian hydrodynamics code of the adiabatic expansion of a supernova into the surrounding medium. The early expansion follows Chevalier's analytic self-similar solution until the reverse shock reaches the ejecta core. We follow the expansion as it evolves towards the adiabatic blast wave phase. Some memory of the earlier phases of expansion is retained in the interior even when the outer regions expand as a blast wave. We find the results are sensitive to the initial configuration of the ejecta and to the placement of gridpoints. 6 refs., 2 figs.
Date: June 8, 1987
Creator: Band, D.L. & Liang, E.P.

Advanced high-field coil designs: 20 TESLA

Description: This study of the technology required for producing large high-field coils has shown that, with some extensions to our present technological base, feasible designs are achievable. The resulting magnets could well make a paramount contribution to the national mirror-fusion endeavor.
Date: August 8, 1983
Creator: Hoard, R.W.; Cornish, D.N.; Scanlan, R.M.; Zbasnik, J.P.; Leber, R.L.; Hickman, R.B. et al.

Application of analytical methods for jointed rock as part of a drift design methodology for the Yucca Mountain Project

Description: The Yucca Mountain Project, managed by the Nevada Operations Office of the US Department of Energy (DOE), is examining the feasibility of siting a repository for high-level nuclear waste at Yucca Mountain, on and adjacent to the Nevada Test Site. Excavation stability will be required during construction, waste emplacement, retrieval (if required), and closure, covering a period of approximately 100 years. In order to incorporate a means of evaluating excavation stability in the design process, a drift design methodology has been developed. This methodology uses both empirical and analytical methods in conjunction with detailed descriptions of site conditions to evaluate a proposed design. At present, the emphasis is on analytical numerical methods because of the limited experience, in tuff at elevated temperatures. This paper describes the proposed methods for analysis of systematically jointed, isotropically jointed, and widely spaced, discretely jointed rock masses. Loads resulting from in situ stress, thermal expansion, and seismic events are considered. Criteria for strength and failure of intact rock and the rock mass are applied to analysis results to assess the stability of proposed drift designs and to guide the design of the ground support system.
Date: December 8, 1989
Creator: Costin, L.S.; Bauer, S.J. & Hardy, M.P.

Atomic vapor laser isotope separation

Description: Atomic vapor laser isotope separation (AVLIS) is a general and powerful technique. A major present application to the enrichment of uranium for light-water power reactor fuel has been under development for over 10 years. In June 1985 the Department of Energy announced the selection of AVLIS as the technology to meet the nation's future need for the internationally competitive production of uranium separative work. The economic basis for this decision is considered, with an indicated of the constraints placed on the process figures of merit and the process laser system. We then trace an atom through a generic AVLIS separator and give examples of the physical steps encountered, the models used to describe the process physics, the fundamental parameters involved, and the role of diagnostic laser measurements.
Date: November 8, 1985
Creator: Stern, R.C. & Paisner, J.A.

Automatic gas-levitation system for vacuum deposition of laser-fusion targets

Description: An improved simple system has been developed to gas-levitate microspheres during vacuum-deposition processes. The automatic operation relies on two effects: a lateral stabilizing force provided by a centering-ring; and an automatically incremented gas metering system to offset weight increases during coating.
Date: September 8, 1981
Creator: Jordan, C.W.; Cameron, G.R.; Krenik, R.M. & Crane, J.K.

Background radiation in the SLC ir from collimators and tune-up dumps in the ARCS

Description: There are various beam intercepting devices between the interaction point and the beam dumps of the SLC. Of these, the adjustable collimators, a fixed collimator, and the tune-up dumps are expected to intercept enough of the beam to warrant calculating the fluxes inside the interaction hall from them. The fluences of neutrons and photons in the interaction hall from these sources. Whether the beam has passed the interaction point or not is considered important in choosing a source term, primarily for photons. Neutron calculations are done only for giant resonance neutrons. (LEW)
Date: July 8, 1986
Creator: Jenkins, T.M.

Backgrounds to the detection of two-body hadronic B decays

Description: We consider backgrounds to the detection of the two-body hadronic decay modes of neutral B mesons and baryons. The largest background is due to the correlated production of pairs of high-p/sub T/ hadrons in the target, but this can be adequately rejected provided the experimental apparatus has sufficient resolution in mass and decay vertex. Another possible source of background arises from the production and decay of charmed and strange particles. Since these particles can travel considerable distances before decaying, they can give rise to backgrounds which may not be rejectable by means of vertex cut. We have simulated several backgrounds from charm, and we find them to be small compared to the expected level of signal. 8 refs., 1 fig., 2 tabs
Date: January 8, 1988
Creator: Kaplan, D.M.; Peng, Jen-Chieh; Abrams, G.S. & Stockdale, I.E.

Bio-oxidation of thiocyanates typical of coal conversion effluents. Final report

Description: Thiocyanates have been found in most coal conversion and coke plant effluents. The objectives of this study were to develop data for the biological degradation fate kinetics of thiocyanate removal, and to develop material balance information for the fate of sulfur and nitrogen resulting from such bio-decomposition of aqueous thiocyanates. A literature review of thiocyanate bio-degradation indicates that while much biochemistry information is available, little information in the biological processing arena is known. Based on both batch and continuous culture experiments utilizing an activated sludge type of system with strictly thiocyanate degradating organisms, the specific utilization rate for SCN degradation was found to follow a substrate inhibition biokinetic relationship as: d(SCN)/dt-X = 2.24/(1 + (5/SCN) + (SCN/1340)/sup 6/) where; d(SCN)/dt-X = lb SCN used/lb biomass-day, SCN = mg/L SCN in effluent. The observed biomass sludge production rate was quantified as a function of sludge age in the bio-reactor. The major metabolic by-products of SCN aerobic biodegradation are ammonia and sulfate, with such formation being stochiometric with SCN. High levels of SCN in coal conversion and Stretford system effluents may lead to biological nitrification process requirements to be added to the wastetreatment scheme for compliance with BAT effluent ammonia discharge restrictions.
Date: January 8, 1981
Creator: Neufeld, R. D.; Mattson, L. & Lubon, P.

Busing for School Desegregation

Description: The mandatory transportation of school children to desegregate public elementary and secondary schools is an issue of deep contention throughout our society. The House of Representatives has approved language for the Department of Justice FY82 authorization bill (H.R. 3462) restricting the Department's involvement in actions requiring school busing. On Mar. 2, 1962, t h e Senate approved the version of the Department of Justice F Y 8 2 authorization Bill (S. 951) with language restricting the Justice Department's involvement in busing actions as well as imposing limits on the busing plans Federal courts can impose. S. 551 was then sent to the House for consideration. Hearings on S. 951 before a house Judiciary subcommittee began on June 1'7, 1982.
Date: July 8, 1982
Creator: Stedman, James B.

Calculation of the chemical behavior of highly concentrated geothermal brines

Description: In this report, the authors describe the development of a chemical equilibrium model for hydrothermal waters based on the semiempirical equations of aqueous electrolyte solutions recently introduced by Pitzer and co-workers. Accurate solubility predictions (usually within 5-10% of experimental results) can be made for ionic strengths 0-20m. Comparison with experimental data indicates that a theory parameterized by binary and ternary data can be used to accurately predict solubilities in much more complex mixtures. Mineral solubilities calculated with this model are compared with those calculated from other currently available models. Whereas the predictions are typically within 5%, the ion pairing models are substantially in error at low ionic strengths. Recent results parameterizing the H{sub 2}S and SiO{sub 2} systems will be presented.
Date: October 8, 1982
Creator: Moller-Weare, Nancy & Weare, John H.

Calibration of a neutron log in partially saturated media IV: effects of sonde-wall gap

Description: A gap between a neutron sonde and the wall of a borehole can have a significant effect on the observed count rate. This effect was determined experimentally to be linear with gaps as large as 2.5 cm. The count rate is given by N/sub N/ = K/sub 0/ + K/sub 1/g where K/sub 0/ is the count rate that would be observed at zero gap, and g is the gap. The parameters K/sub 0/ and K/sub 1/ are dependent on both water (ie. hydrogen) content and bulk density. In many situations failure to correct the count rate for this gap effect can result in a significant degradation in the accuracy of the water content calculated from the count rate. In a dry borehole, K/sub 1/ is small at zero formation water content, and increases with formation water content. In a water-filled borehole, K/sub 1/ is large at zero formation water content, and tends to decrease with increasing formation water content, becoming zero, as of course it must, if the formation is pure water. The absolute value of K/sub 1/ increases with increasing density. A representation was determined for K/sub 0/ and K/sub 1/ from experimental data. This representation can be used to adjust the count rate at a given gap to equal its zero-gap value. The accuracy of the zero gap equation can then be recovered.
Date: March 8, 1984
Creator: Axelrod, M.C. & Hearst, J.R.

Cathodic protection for geothermal wells

Description: A study was conducted to determine the current requirements for cathodic protection of geothermal wells. Oil well technology was applied in this study. Results of laboratory tests and field tests are presented. Attenuation calculations indicate that the cathodic protection current determined from field tests would protect the specific individual geothermal well.
Date: October 8, 1982
Creator: Ohnysty, B.; Slattery, D.G. & Morris, M.

Cathodic protection of carbon steel in simulated geothermal environments

Description: The applicability of cathodic protection to mitigate corrosion of carbon steel in two different environments containing H{sub 2}S has been investigated using impressed current and sacrificial anode techniques. Results of impressed current tests conducted under potential control shows that the weight loss can be reduced significantly by shifting the potential of the metal 60 to 80 mV cathodic to the open circuit potential. The relationship between the applied current and the potential shift shows that the current requirement does not necessarily increase with the voltage shift, thus implying that the cost of cathodic protection may not increase in proportion to the protection achieved. The feasibility of using zinc as a sacrificial anode in the environment of interest has also been studied.
Date: October 8, 1982
Creator: Bandy, R. & van Rooyen, D.

Characteristics of A-150 plastic-equivalent gas in A-150 plastic ionization chambers for p(66)Be(49) neutrons

Description: The evaluation of a gas mixture having an atomic composition similar to that of A-150 TE-plastic has been extended to a high energy neutron therapy beam. A-150 gas, air and methane-based TE gas were each flowed through A-150 plastic-walled ion chambers of different sizes and irradiated with p(66)Be(49) neutrons. A tentative value for anti W(A-150) of 27.3 +- 0.5 J C/sup -1/ was derived for this beam. The anti W value of the A-150 gas mixture is compared to those of methane-based TE gas and of air for the p(66)Be(49) neutron beam as well as to corresponding values found in similar experiments using 14.8 MeV monoenergetic neutrons. 17 references, 3 figures, 3 tables.
Date: July 8, 1982
Creator: Awschalom, M.; Rosenberg, I.; Ten Haken, R.K.; Pearson, D.W.; Attix, F.H. & DeLuca, P.M.

The characterization of Nb/sub 3/Sn superconductors for use in magnets of 19 T and greater

Description: Increased resolution of NMR spectrometry will require the use of very high field Nb/sub 3/Sn superconducting magnets. Here we report the results of our investigation into mechanical and temperature effects on internal-Sn superconductors similar to those proposed for use in a 900 MHz, 21 T NMR magnet system. Thermal precompression was found to be about 0.225%, and the irreversible strain was about 0.8%. Fatigue degradation was not observed at cyclic intrinsic strains below 0.575%. Additions of reinforcing steel in cable conductors was found to reduce the critical current by as much as 50% compared to similar, unreinforced cables. Reduction of the testing temperature to 2.3 K did not increase the critical current in steel-reinforced cables to a level significantly above that of unreinforced samples. 4 refs., 3 figs., 1 tab.
Date: August 8, 1989
Creator: Summers, L.T.; Strum, M.J. & Miller, J.R.

Chloride content of dissolver solution from Rocky Flats scrub alloy ninth and tenth campaigns following head end treatment

Description: F-Canyon continues to obtain excellent chloride removal from Rocky Flats scrub alloy (RFSA) dissolver solution during head end treatment. One single batch of solution from the ninth RFSA campaign, dissolved in January and February of this year, and two batches from the tenth campaign, dissolved in February, have been successfully processed. Following dissolution in Tank 6.4D, chloride was precipitated with mercurous ion added as the nitrate. The precipitate, Hg{sub 2}Cl{sub 2}, was concurrently removed with the gelatin floc via centrifugation. For each of these three batches processed, a set of duplicate samples was obtained from Tank 11.2 or from Tank 13.3, containing the head end product. The samples were preanalyzed by Laboratories Department for density and acidity to ensure them to be representative of the tank`s contents prior to chloride analysis by the Separations Technology Laboratory. Previous work indicated that in order to protect downstream canyon equipment from chloride attack, the chloride content of RFSA solutions should be less than 100 ppm. All batches from these two RFSA campaigns meet this criterion.
Date: March 8, 1988
Creator: Holcomb, H.P.

Chloride content of Rocky Flats scrub alloy twelfth campaign solution following head end treatment

Description: A single batch of dissolver solution from the twelfth Rocky Flats Scrub Alloy (RFSA) campaign has been analyzed for chloride content following head end treatment to reduce its concentration. Scrub alloy buttons were dissolved in Tank 6.4D during July. In subsequent head end processing, chloride was precipitated with mercurous ion added as the nitrate. The precipitate, Hg{sub 2}Cl{sub 2}, was co-removed with the gelatin floc via centrifugation. Duplicate samples from Tank 11.2, containing the head end product, produced excellent agreement between their density measurements and acid analyses, indicating them to be truly representative of the tank`s contents. Duplicate aliquots from each of these solutions were analyzed using the turbidimetric chloride method developed in the Separations Technology Laboratory. These resulted in an average chloride value of 53 ppm ({micro}g/mL) chloride for the head end product. Relative standard deviation of the measurement was {+-}6 ppm (n = 4), a precision of {+-}11%. Such a variance is normal at this low chloride level. Since initial chloride values prior to head end averaged 1365 ppm (0.0385M), as analyzed by Laboratories Department, a chloride DF of approximately 26 was obtained. Such a reduced chloride level (to less than 100 ppm) in the treated solution will permit further canyon processing with minimal corrosion.
Date: August 8, 1988
Creator: Holcomb, H. P.

Combination free-electron and gaseous laser

Description: A multiple laser having one or more gaseous laser stages and one or more free electron stages is described. Each of the free electron laser stages is sequentially pumped by a microwave linear accelerator. Subsequently, the electron beam is directed through a gaseous laser, in the preferred embodiment, and in an alternative embodiment, through a microwave accelerator to lower the energy level of the electron beam to pump one or more gaseous lasers. The combination laser provides high pulse repetition frequencies, on the order of 1 kHz or greater, high power capability, high efficiency, and tunability in the synchronous production of multiple beams of coherent optical radiation.
Date: June 8, 1981
Creator: Brau, C.A.; Rockwood, S.D. & Stein, W.E.