The beam quality or brightness of an electron beam produced with field immersed emission is studied with two models. First, an envelope formulation is used to determine the scaling of brightness with current, magnetic field and cathode radius, and examine the equilibrium beam radius. Second, the DPC computer code is used to calculate the brightness of two electron beam sources.

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Pulsed laser annealing and ion beam mixing have been used as surface modification techniques to enhance the physical properties of polycrystalline ..cap alpha..-SiC. Thin Ni overlayers (20 nm to 100 nm) were evaporated onto the SiC surface. The specimens were subsequently irradiated with pulses of a ruby or krypton fluoride (KrF) excimer laser or bombarded with high energy Xe/sup +/ or Si/sup +/ ions. Both processes are nonequilibrium methods and each has been shown to induce unique microstructural changes at the SiC surface which are not attainable by conventional thermal treatments. Under particular (and optimum) processing conditions, these changes considerably increased the mechanical properties of the SiC; following laser irradiation, the fracture strength of the SiC was increased by as much as 50%, but after ion beam mixing, no strength increase was observed. High resolution cross-section transmission electron microscopy (X-TEM), scanning electron microscopy (SEM), and Rutherford backscattering techniques were used to characterize the extent of mixing between the Ni and the SiC as a result of the surface modification.

During 1985, interest has been revived at LLNL in tandem mirrors operating in the negative-potential mode. The negative tandem is formed by combining ECRH-sustained hot electron end cell plasmas with pumping mechanisms to remove trapped ions from the end cells. No sloshing ions are required. The resulting negative potential in the end cells confines the central cell electrons. The requirement of charge neutrality causes the ambipolar potential of the central cell to become negative relative to the end wall (hence, the name ''negative' tandem mirror), thereby providing central cell ion confinement. This potential distribution is the exact inverse of the axial distribution for the conventional (positive) tandem mirror without thermal barriers. In the negative tandem mirror, central cell electrons are confined electrostatically, end cell electrons are confined magnetically, and ions are confined electrostatically everywhere. In this report, we briefly assess the reactor issues pertinent to the operation of the tandem mirror in the negative mode. 7 refs., 5 figs.

Sampling was conducted in John Day Reservoir to collect walleye, northern squawfish and smallmouth bass. Changes in distributions during sampling were characterized from changes in catch per unit effort (CPUE) in sampling areas. Observed movements of marked and radiotagged fish were examined and used to define discrete populations. Abundances were estimated using a modified Schnabel multiple mark and recapture estimator. Abundance estimates were corrected for angler harvest, size specific vulnerability to gear, recruitment due to growth and tag loss during sampling. Age composition of catch was determined to characterize relative contributions of various year classes to the populations. Ages at which fish were fully recruited to gear were defined by catch curves. Survival of fully recruited year classes was calculated from differences in CPUE's between 1984 and 1985. Mean length at age was estimated and used to determine age specific incremental growth. Eighty-eight percent of walleye were caught in McNary tailrace or Irrigon-Paterson, whereas 95% of smallmouth bass were caught from Irrigon-Paterson to the John Day forebay. Abundances of walleye and northern squawfish with fork lengths greater than 250 mm and smallmouth bass with fork lengths greater than 200 mm were estimated to be 16,219, 95,407, and 11,259. Anglers harvested …

Second regions of stability to the ideal ballooning modes have been shown to exist in large-aspect-ratio circular and small-aspect-ratio bean-shaped tokamaks. We report on the existence of these second stability regions in finite-aspect-ratio dee-shaped tokamaks. We also report on the discovery of a second-stable region with respect to the n = 1 external kink mode in a bean-shaped plasma. The role of the shear and current profile in determining these regions of parameter space are discussed. 13 refs., 6 figs.

Advanced commercial tokamak studies were performed by the Fusion Engineering Design Center (FEDC) as a participant in the Tokamak Power Systems Studies (TPSS) project coordinated by the Office of Fusion Energy. The FEDC studies addressed the issues of tokamak reactor cost, size, and complexity. A scoping study model was developed to determine the effect of beta on tokamak economics, and it was found that a competitive cost of electricity could be achieved at a beta of 10 to 15%. The implications of operating at a beta of up to 25% were also addressed. It was found that the economics of fusion, like those of fission, improve as unit size increases. However, small units were found to be competitive as elements of a multiplex plant, provided that unit cost and maintenance time reductions are realized for the small units. The modular tokamak configuration combined several new approaches to develop a less complex and lower cost reactor. The modular design combines the toroidal field coil with the reactor structure, locates the primary vacuum boundary at the reactor cell wall, and uses a vertical assembly and maintenance approach. 12 refs., 19 figs.

The three-dimensional diagnostic wind field model (MATHEW) and the particle-in-cell transport and diffusion model (ADPIC) are used by the Atmospheric Release Advisory Capability (ARAC) for real-time assessments of the consequences from accidental releases of radioactivity into the atmosphere. For the dispersion of hazardous heavier-than-air gases, a time-dependent, three-dimensional finite element model (FEM3) is used. These models have been evaluated extensively against a wide spectrum of field experiments involving the release of chemically inert tracers or heavier-than-air gases. The results reveal that the MATHEW/ADPIC models are capable of simulating the spatial and temporal distributions of tracer concentration to within a factor of 2 for 50% of the measured tracer concentrations for near surface releases in relatively flat terrain and within a factor of 2 for 20% of the comparisons for elevated releases in complex terrain. The FEM3 model produces quite satisfactory simulations of the spatial and temporal distributions of heavier-than-air gases, typically within a kilometer of the release point. The ARAC consists of a centralized computerized emergency response system that is capable of supporting up to 100 sites and providing real-time predictions of the consequence of transportation accidents that may occur anywhere. It utilizes pertinent accident information, local and regional meteorology, …

The Analytical Chemistry Laboratory is a full-cost-recovery service center, with the primary mission of providing a broad range of technical support services to the scientific and engineering programs at ANL. In addition, ACL conducts a research program in analytical chemistry, works on instrumental and methods development, and provides analytical services for governmental, educational, and industrial organizations. The ACL handles a wide range of analytical problems, from routine standard analyses to unique problems that require significant development of methods and techniques. The purpose of this report is to summarize the technical and administrative activities of the Analytical Chemistry Laboratory (ACL) at Argonne National Laboratory (ANL) for Fiscal Year 1985 (October 1984 through September 1985). This is the second annual report for the ACL. 4 figs., 1 tab.

Savannah River Plant (SRP) Waste Management Technology Department retained Woodward-Clyde Consultants to oversee collection and analysis of soil core samples and to develop closure plans for the F- and H-Area seepage basins. Waste Management Technology requested the SRL Environmental Sciences Division to provide database management and quality assurance of analytical data from the F- and H-Area seepage basin soil cores. The establishment of a computerized database and data reporting in table and graph forms were incorporated into the database management program. A database of analytical results for radionuclides, cations, and anions was constructed on an IBM 3081 mainframe computer. Two subcontractors were chosen to perform the laboratory analyses of the soil cores. This document provides a discussion of the database management and the soil sampling and analysis studies.

In view of the recent shift in emphasis of the DOE/Industry HTGR development efforts to smaller modular designs it became necessary to review the modelling needs and the codes available to assess the safety performance of these new designs. This report provides a final assessment of the most urgent modelling needs, comparing these to the tools available, and outlining the most significant areas where further modelling is required. Plans to implement the required work are presented. 47 refs., 20 figs.

Investigations of barometric pressure testing of NTS nuclear chimneys were reviewed. This review includes the models used in the interpretation, methods of analysis, and results. Analytic and semi-analytic models were presented and applied to both historical data and new data taken for this current project. An interpretation technique based on non-linear least squares methods was used to analyze this data in terms of historic and more recent chimney models. Finally, a detailed discussion of radioactive gas transport due to surface barometric pressure fluctuations was presented. This mechanism of transport, referred to as ''barometric pumping,'' is presented in terms of conditions likely to be encountered at the NTS. The report concludes with a discussion of the current understanding of gas flow properties in the alluvial and volcanic areas of the NTS, and suggestions for future efforts directed toward increasing this understanding are presented.

A survey is given of topological-bootstrap-theory aspects that connect objective reality, the S matrix and elementary particles. 3 refs., 9 figs.

One method of adding capacity is to install another array of turbines whose hub height is above the existing array. This report estimates the wake interference that could be expected in a two-level array. Interference is estimated for a typical situation that may be encountered by a wind farm developer. A modified Lissaman array model is used to make the wake interference calculations. The model calculations show that the wake interference between the two levels is small for the turbine characteristics and turbine layouts considered. (The windwise spacings are about 5.4 and 10.8D for the lower and upper levels of turbines, respectively.) Power losses are about 5% or less at rated speed. Thus, two-level arrays may be a viable way of increasing the generating capacity of existing wind farms.

The objective of this program is to determine how retorting process parameters affect the partitioning of Hg, As, Se, and Cd from raw oil shale to spent shale, shale oil, retort water, and offgas. For each of the elements, the objective of this study is to (1) determine the distribution coefficients for each product stream; (2) identify the chemical forms in water, gas, and oil streams, with particular emphasis on inorganic or organometallic species known to be or suspected of being carcinogenic, toxic, or otherwise harmful; (3) investigate the mechanism(s) responsible for mobilization into each product stream for toxic or labile chemical forms identified in item 2 are mobilized into each product stream; and (4) the effect of retorting rate, maximum retorting temperature, and retorting atmosphere on items 1 and 3. A Green River shale from Colorado and a New Albany shale from Kentucky were heated at 1 to 2/sup 0/C/min and at 10/sup 0/C/min to maximum temperatures of 500 and 750/sup 0/C under a nitrogen sweep gas. The product streams were analyzed using a variety of methods including Zeeman atomic absorption spectroscopy, microwave-induced helium plasma spectroscopy, x-ray fluorescence, instrumental neutron activation analysis, high-pressure liquid and silica gel column chromatography, …

Research needs on the climate consequences of nuclear war were discussed. These include: (1) a better definition of the emissions from massive urban fires; (2) the exploration of prescribed forest burns; (3) the dirty cloud problem; (4) microphysical studies of soot; and (5) simulation of the second summer season after nuclear war. (ACR)

Research on Columbia River white sturgeon has been directed at their early life history as it may apply to production and enhancement strategies for management of the species. The river environment in which sturgeon historically migrated, spawned, and reared has changed through development. Habitat changes are expected to precipitate genetic changes in the fish, as well as reduce the fitness in populations. Genetic analysis of samples taken from various locations over the length of the Columbia River have indicated that observed gene frequencies in all areas sampled were not in Hardy-Weinburg equilibrium, which could suggest that the general population is experiencing perturbation in the system. Analysis thus far has exposed few differences between samples from the lower, middle, and upper portions of the system. Allelic differences were identified in fish from the Roosevelt Lake, which may be evidence of unique characteristics among fish from that general area.

The development of numerical models for plasma phenomena and magnetic confinement devices is discussed. The multidimensional Fokker-Planck and transport codes are applied to toroidal mirror and compact toroid devices. Linear and nonlinear resistive magnetohydrodynamics in two and three dimensions are used in the investigation of various fusion devices. 362 refs., 4 tabs. (WRF)

This report describes a comprehensive computer program that allows the user to simulate the performance of realistic coal preparation plants. Use of the simulator requires that the user specify the appearance of the plant configuration, the plant operating conditions, and a description of the coal feed. The simulator will then determine the flowrates within the plant, and a description of each flowrate (i.e., the weight distribution, percent ash, pyritic sulfur and total sulfur, moisture, and Btu content). The simulation program has been written in modular form using the Fortran language. It can be implemented on a great many different types of computers, ranging from large scientific mainframes to IBM-type personal computers with a fixed disk. Part I of this report contains a general description of the methods used to carry out the simulation. Each of the major types of units is described separately, in addition to a description of the overall system analysis. Part II is intended as a user's manual. It contains a listing of the mainframe version of the program, instructions for its use (on both a mainframe and a microcomputer), and output for a representative sample problem. 22 refs., 9 figs., 1 tab.

This report describes a comprehensive computer program that allows the user to simulate the performance of realistic coal preparation plants. The program is very flexible in the sense that it can accommodate any particular plant configuration that may be of interest. This allows the user to compare the performance of different plant configurations and to determine the impact of various modes of operation with the same configuration. In addition, the program can be used to assess the degree of cleaning obtained with different coal feeds for a given plant configuration and a given mode of operation. Use of the simulator requires that the user specify the appearance of the plant configuration, the plant operating conditions, and a description of the coal feed. The simulator will then determine the flowrates within the plant, and a description of each flowrate (i.e., the weight distribution, percent ash, pyritic sulfur and total sulfur, moisture, and Btu content). The simulation program has been written in modular form using the Fortran language. It can be implemented on a great many different types of computers, ranging from large scientific mainframes to IBM-type personal computers with a fixed disk. Some customization may be required, however, to ensure compatibility …

This report presents a research agenda of Consumer Decision and Behavior Projects related to improving, facilitating and planning Building and Community Systems, (BCS) research and development activities. Information for developing this agenda was gathered through focus group and depth interviews with BCS staff, directors and program managers.

The specific objectives of this report are to present a technically detailed site description for the Metallurgical Laboratory basin, to document the manner in which it was modeled by the PATHRAE computer code, and to present the results of the pathway analyses, in terms of both contaminant transport and health risks. This will provide part of a detailed assessment of environmental risks and impacts from the Metallurgical Laboratory both in its present condition and after possible remedial actions to aid in selection of the appropriate remedial action options. In a broader sense, these objectives support the general SRP (Savannah River Plant) operations policy of protecting the environment and the health and safety of the public and operating personnel.

By combining a digitizing system with a contour-to-grid program, digital elevation data may be developed from contour maps automatically for any existing contour map.

The Nuclear Waste Policy Act of 1982 directs the Department of Energy (DOE) to dispose permanently high level radioactive waste and civilian spent nuclear fuel by January 31, 1998. DOE has responded by creating an organizational structure that directs all the activities necessary to carry out the legislative demands. LLNL is conducting research in the earth sciences and is developing some unique computer codes to help establish the feasibility of geologic repositories for nuclear waste. LLNL has several codes under development. This paper examines the administrative and organizational measures that were and still are being undertaken in order to control the development of the two major codes. In the case of one code, the software quality assurance requirements were imposed five years after the code began its development. This required a retroactive application of requirements. The other code is still in the conceptual stages of development and here requirements can be applied as soon as the initial code design begins. Both codes are being developed by scientists, not computer programmers, and both are modeling codes, not data acquisition and reduction codes. Also the projects for which these codes are being developed have slightly different software quality assurance requirements. All these …