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Single particle behavior in plasmas

Description: The paper follows the history of a neutral atom or molecule into a plasma--ionization, dissociation, radiation,--until it becomes a set of charged particles moving in the electromagnetic fields of the plasma system. The various useful forms of the method of averaging are displayed and applied to calculation of constants of motion. The breakdown of these constants is discussed along with some of the implications for fusion systems.
Date: March 10, 1977
Creator: McNamara, B.
open access

COMP: a BASIC language nonlinear least-squares curve fitting program

Description: COMP is an interactive nonlinear least squares routine written in BASIC language and used to obtain estimates of parameters in nonlinear functions and to approximate their associated statistical errors. The program uses the linearizing (or Taylor Series) expansion of partial derivatives outlined in Draper and Smith, (1966, pp. 267 to 270). Therefore, partial derivatives must be supplied (as well as the function) by the user for any new models not currently contained in the programs. When a linearizing method is used to estimate parameters in a nonlinear model, all the usual procedures of linear regression theory can be applied. However, the results so obtained are only valid insofar as the linearized form approximates the true model. All of the statistics computed by COMP should be viewed with this restriction in mind. The output of COMP includes the variance-covariance matrix, t-tests for parameters, Von Neumann's ratio, observed, predicted and residual values, the error mean square, and an optional procedure to evaluate heteroscedasticity.
Date: November 1, 1977
Creator: Thomas, J. M.; Cochran, M. I.; Watson, C. R. & Eberhardt, L. L.
open access

Correlation of alluvial deposits at the Nevada Test Site

Description: Because characteristics of rock layers and problems in drilling must be studied before radioactive waste can be safely contained, an evaluation was made of methods for correlating alluvial deposits at Yucca Flat of the Nevada Test Site (NTS). Although correlation of Tertiary volcanic tuff beds at the NTS has been successfully achieved, correlation of stratigraphic zones in the overlying alluvium has posed technical difficulties. We have evaluated several methods for correlating alluvial deposits from drillholes, including electric resistivity logs (E logs), visual examination of sidewall samples and comparison of their carbonate (CO/sub 2/) content, downhole stereo photography for identifying debris flow deposits, caliche age-dating, and specific yield and permeability measurements of deposits. For predicting the thickness of zones having similar physical properties in the alluvium, E log measurements were found to be the most useful of these methods.
Date: September 30, 1977
Creator: Grothaus, B. & Howard, N.
open access

Note on the cryostatic stability of superconducting composites

Description: A careful discussion is given of the ''equal area condition'' developed by Maddock et al. In order to make the essential points as clear as possible, analytical solutions are derived under simplifying assumptions (simple model for heat transfer by nucleate and film boiling liquid helium; constant heat conduction and specific heat) instead of using more realistic but less controllable computer calculations. A quantitative definition of the concept of a long wire is given. Numerical examples for the Maddock transition characterized by the equal area condition are given for a long superconducting composite with linear cooling and for a liquid helium-cooled resistance wire of finite length. In addition, cases are shown where instead of applying the equal area stability condition, time-dependent solutions should be considered.
Date: February 1, 1978
Creator: Gauster, W. F.
open access

Comparative assessment of energy-economy interactions

Description: This analysis is concerned with the impact of energy-policy measures on the level, growth, and structure of the US economy. In particular, the nature and magnitude of the causal relationship between variations in the prices of various energy forms and economic performance, as measured by real gross national product (GNP), is studied. The combined Brookhaven National Laboratory/Dale W. Jorgenson Associates (BNL/DHA) energy-economy model system is used to determine the economic effects of three energy-price futures combined with an invariant set of energy policies. The price alternatives are intended to characterize the uncertainty that exists in the policy-planning environment. In addition, the results are compared to those obtained from another DOE-sponsored analysis which used the Data Resources, Incorporated (DRI) quarterly macroeconomic model to assess the effects of these same three cases. Significant numerical differences in the results from these modeling systems are observed and are attributed to structural differences between the two methodologies. The methodological issues emerging from this comparison have important policy implications which are independent of the specific numerical conclusions. Since it is uncertain which, if either, of the models is correct, the use of one for policy analysis entails the risk that policy will be predicated on inaccurate information. This risk is analyzed within an explicit framework and clear decision rules for information selection and the choice between the modeling systems are formulated.
Date: December 1, 1978
Creator: Goettle, R.J. IV; Hudson, E.A. & Lukachinski, J.
open access

Defects in metal crystals. Progress report, May 1, 1973--April 30, 1974

Description: Progress was made in the following areas: FIM (field ion microscopy) studies of defects in W irradiated with W ions or electrons; FIM studies of Au irradiated with Au or Xe ions; FIM and electrical resistivity study of vacancy defects in quenched W; FIM studies of dilute Pt alloys; measurement of the range of focused replacement sequences in Au; investigation of grain boundary strtucture (using Au); FIM observation of dissociated screw dislocations in Mo; calculation of properties of point defects in metals; and atom probe FIM. (auth)
Date: January 1, 1974
Creator: Balluffi, R.W. & Seidman, D.N.
open access

Development of a High Velocity Solid Particle Launcher for Laboratory Erosion Studies. [Reentry Vehicle Heat Shields]

Description: A solid particle launcher for laboratory erosion studies has been developed and successfully demonstrated. Performance of the launcher is predicted by a two-dimensional, time-dependent theoretical analysis to within the experimental uncertainty. The present device accelerates 100 μm diameter glass spheres to velocities of 2.1+/- 0.6 km/sec. The system is safe, reliable, and has a test repetition of about 2 shots/hour.
Date: March 1, 1975
Creator: Aeschliman, D. P.; Mulac, A. J.; Guzman, J. A.; Eaton, R. R. & Fox, R. L.
open access

Solar-thermal energy conversion and storage: cyclohexane dehydrogenation. Progress report, 30 September 1977-30 June 1978

Description: The objective of this project is to provide research support for the benzene/cyclohexane heat pipe development program at Sandia. The kinetics of the cyclohexane decomposition (energy collection) reaction over a commercially available naphtha reforming catalyst (RD-150, Englehard Industries) in the temperature range 400 to 800/sup 0/F and pressures of 1 to 40 atmospheres were measured. Significant amounts of side products such as toluene and butane were identified at temperatures above 550/sup 0/F at atmospheric pressure and significant mass transfer limitations on conversions were observed at the higher space velocities and higher temperatures. No significant decreases in catalyst activity were measured at temperatures below 800/sup 0/F. However, at 800/sup 0/F there was a significant decrease in catalyst activity which does not appear to be a poisoning problem but a thermal limitation on catalyst effectiveness. A test facility has been fabricated to study the behavior of the benzene/cyclohexane (or any other gas phase catalytic reaction) system and its catalysts under long term cycling at temperatures up to 1000/sup 0/F, and pressures up to 1000 psig at a wide variety of space velocities. A mathematical model was developed which simulates the dynamic behavior of the collector (endothermic) reactor and allows the evaluation of such things as startup, shutdown, switching and process control algorithms.
Date: July 1, 1978
Creator: Ritter, A.B.; DeLancey, G.B.; Schneider, J. & Silla, H.
open access

Geothermal resources in California: the problems and the potential

Description: The report is presented under the following section headings: introduction; conclusions and recommendations; legislative activity in 1973; United Nations Geothermal Conference; International Geothermal Conference--1975; National Conference on Geothermal Energy, May 10--11, Palm Springs, Calif.; Imperial Valley field trip and joint interim hearing October 16--17, 1973 (Senate Committee on Natural Resources and Wildlife on Senate Bill 577 in San Diego); hearing of the Subcommittee on Geothermal Resources and the Senate Committee on Public Utilities and Corporations, Nov. 12, 1973 in San Francisco (public access to steam at The Geysers); hearing of the Senate Committee on Natural Resources and Wildlife on the continued availability of natural gas and other sources of energy, Nov. 15, 1973, in Martinez, Calif; and Appendix. (JGB)
Date: January 1, 1973
open access

Redox reactions involving chromium, plutonium, and manganese in soils

Description: Plutonium speciation in soils is discussed. Chromium was selected as a model for studying soil Pu. Similarities between Cr and Pu are pointed out, and a hypotheses concerning Pu speciation in soils is presented. Findings from Cr oxidation studies that may be relevant to the problem of Pu oxidation in soils are discussed. (JGB)
Date: January 1, 1979
Creator: Amacher, M.C. & Baker, D.E.
open access

Video monitoring system for enriched uranium casting furnaces

Description: 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 system reliability.
Date: March 1, 1978
Creator: Turner, P. C.
open access

Stress corrosion cracking of uranium--niobium alloys

Description: 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 most reactive alloy, U-2/sup 1///sub 4/% Nb, while O/sub 2/ is primarily responsible for cracking in the more corrosion resistant alloys, U-6 and 8% Nb. The 4/sup 1///sub 2/% alloy was found to be susceptible in both H/sub 2/O and O/sub 2/ environments.
Date: March 1, 1978
Creator: Magnani, N.J.
open access

Selected constituents in the smoke of domestic low tar cigarettes

Description: Thirty-two brands of domestic commercial low tar and nicotine cigarettes were analyzed for their production of tar, nicotine, nitrogen oxides (as nitric oxide), hydrogen cyanide, acrolein, carbon monoxide and carbon dioxide under standard analytical smoking conditions. Results are compared with published data for certain brands.
Date: December 1, 1977
Creator: Griest, W. H.; Quincy, R. B. & Guerin, M. R.
open access

Pilot plant test plan, Task IX: technical support. Industrial Low-Btu Fuel Gas Demonstration-Plant Program

Description: The objective of the AAG pilot plant operation is to provide process data for the gasification and related sections of the demonstration plant. Since the pilot plant will not operate at the actual pressure of the demonstration plant, it is planned to perform tests at two different pressures to obtain a sound basis for pressure scale-up. Other objectives are listed briefly.
Date: January 1, 1978
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