Substitutional carbon on an arsenic lattice site is the shallowest and one of the most dominant acceptors in semi-insulating Liquid Encapsulated Czochralski (LEC) GaAs. However, the role of this acceptor in determining the well known W'' shape spatial variation of neutral EL2 concentration along the diameter of a LEC wafer is not known. In this thesis, we attempt to clarify the issue of the carbon acceptor's effect on this W'' shaped variation by measuring spatial profiles of this acceptor along the radius of three different as-grown LEC GaAs wafers. With localized vibrational mode absorption spectroscopy, we find that the profile of the carbon acceptor is relatively constant along the radius of each wafer. Average values of concentration are 8 {times} 10E15 cm{sup -3}, 1.1 {times} 10E15 cm{sup -3}, and 2.2 {times} 10E15 cm{sup -3}, respectively. In addition, these carbon acceptor LVM measurements indicate that a residual donor with concentration comparable to carbon exists in these wafers and it is a good candidate for the observed neutral EL2 concentration variation. 22 refs., 39 figs.

In this report we investigate in some detail the geometry and the cost of two modifications in the configuration of the SSC. 3 refs., 7 figs.

The primary purpose of this report is to provide a thorough and systematic planning document to reflect the continuing process of site assessment, strategy development, and planning for the current and long-term control of environmental issues, waste management practices, and remedial action requirements. The docuemnt also provides an estimate of the resources required to implement the current plan. This document is not intended to be a budget document: it is, however, intended to provide guidance to both Martin Marietta Energy Systems, Inc., and the US Department of Energy (DOE) Management as to the near order of magnitude of the resources (primarily funding requirements) and the time frame required to execute the strategy in the present revision of the plan. The near-term (one to three years) part of the plan is a realistic assessment of the current program and ongoing capital projects and reflects the efforts preceived to be necessary to comply with all current state and federal regulations and DOE orders. It also should be in general agreement with current budget (funding) requests and obligations for these immediate years. Beyond the immediate time frame, the document reflects the strategy and the project and funding estimates as a snapshot at the …

On September 6, 1987, about 6:00 a.m., a fire was discovered in the community building at Council, Alaska, where 12 radioluminescent (RL) light panels containing approximately 3000 Ci were stored. All of the tritium in the panels was released as a result of the fire. This report summarizes the recovery of the remains of the panels destroyed in the fire and investigations completed to evaluate the fire site for possible exposure of community residents or contamination by tritium release in the environment. Based on the analysis of urine samples obtained from individuals in the community and from Pacific Northwest Laboratory personnel participating in the recovery operation, no evidence of exposure to individuals was found. No tritium (above normal background) was found in water and vegetation samples obtained at various locations near the site. 12 figs., 3 tabs.

This research project involves the design, synthesis and study of molecules which mimic many of the important aspects of photosynthetic electron and energy transfer. The knowledge gained from the study of synthetic model systems which abstract features of the natural photosynthetic apparatus can be used to design artificial photosynthetic systems which employ the basic physics and chemistry of photosynthesis to help meet mankind's energy needs. More specifically, the proposed models are designed to mimic the following aspects of natural photosynthetic multistep electron transfer: electron donation from a tetrapyrrole excited singlet state, electron transfer between tetrapyrroles, electron transfer from tetrapyrroles to quinones, and electron transfer between quinones with different redox properties.

Scientific and technical journals in biology and medicine have extensively covered a debate about whether and how to determine the function and order of human genes on human chromosomes and when to determine the sequence of molecular building blocks that comprise DNA in those chromosomes. This report surveys the points made so far in the debate that involves science, technology, and politics, focusing on those that most directly influence the policy options facing the U.S. Congress.

The staff paper is part of a larger, ongoing OTA assessment of the ozone nonattainment issue, requested by the Senate Committee on Environment and Public Works and the House Committee on Energy and Commerce.

The work undertaken under this Contract is the prosecution of the preconstruction activities, including preliminary engineering design, well field development, completion of environmental review and prosecution of permits, and the economic and financial analysis of the facility. The proposed power plant is located in northeastern California in Lassen County, approximately 25 miles east of the town of Susanville. The power plant will use a combination of wood residue and geothermal fluids for power generation. The plant, when fully constructed, will generate a combined net output of approximately 33 megawatts which will be sold to Pacific Gas and Electric Company (PG E) under existing long-term power sales contracts. Transfer of electricity to the PG E grid will require construction of a 22-mile transmission line from the power plant to Susanville. 11 refs., 12 figs., 7 tabs.

This report is the second volume of the Recovery Efficiency Test Phase I Report of Activities. Volume 1 covered selection, well planning, drilling, coring, logging and completion operations. This volume reports on well testing activities, reclamation activities on the drilling site and access roads, and the results of physical and mechanical properties tests on the oriented core material obtained from a horizontal section of the well. 3 refs., 21 figs., 10 tabs.

This document discusses the development of quantitative simulation models for the investigation of geologic systems. The selection of variables, model verification, evaluation, and future directions in quantitative dynamic stratigraphy (QDS) models are detailed. Interdisciplinary applications, integration, implementation, and transfer of QDS are also discussed. (FI)

The work undertaken under this Contract is the prosecution of the preconstruction activities, including preliminary engineering design, well field development, completion of environmental review and prosecution of permits, and the economic and financial analysis of the facility. The proposed power plant is located in northeastern California in Lassen County, approximately 25 miles east of the town of Susanville. The power plant will use a combination of wood residue and geothermal fluids for power generation. The plant, when fully constructed, will generate a combined net output of approximately 33 megawatts which will be sold to Pacific Gas and Electric Company (PGandE) under existing long-term power sales contracts. Transfer of electricity to the PGandE grid will require construction of a 22-mile transmission line from the power plant to Susanville. 11 refs., 12 figs., 4 tabs.

In accordance with the requirements of the Remedial Investigation/Feasibility Study (RI/FS) Project Quality Assurance Plan, this Waste Management Plan establishes clear lines of responsibility and authority, documentation requirements, and operational guidance for the collection, identification, segregation, classification, packaging, certification, and storage/disposal of wastes. These subjects are discussed in the subsequent sections of this document.

The Rayleigh-Taylor instability response of elastic-plastic solids can be modeled by approximate means. However, neither the linear elastic response equation nor the so-called /open quotes/minimum amplitude/close quotes/ instability criterion derived from rigid plastic analyses is sufficient to describe overall stability characteristics at very large driving pressures. We compare several versions of the modal or one-degree-of-freedom approximation technique and indicate the common features which must be included to obtain the qualitative response seen in numerical experiments.

This document describes the relationship between indoor radon exposure, cigarette smoking, and lung cancer. The author explains the sources of radon, the tissues at risk, the human populations most likely to be affected, and the estimates of lung cancer in the population. 6 refs., 2 tabs. (TEM)

Progress is reported in the field of condensed matter physics in the area of two-dimensional critical phenomena, specifically results allowing complete classification of all possible two-dimensional critical phenomena in a certain domain. In the field of high energy physics, progress is reported in string and conformal field theory, and supersymmetry.

The general goals of this research project is to enhance and transfer to DOE a new computer simulation model for analyzing the performance and cost of integrated environmental control (IEC) systems for coal-fired power plants. A unique capability of this model is the probabilistic representation of uncertainty in model parameters. This capability allows performance and cost to be quantified stochastically in comparing conventional technologies with advanced systems offering improved cost and/or effectiveness for SO{sub 2} and NO{sub x} removal. Several pre-combustion and post-combustion processes of interest to DOE have been selected for detailed modeling and analysis as part of this project.

The data base for thermal expansion, elastic constants, compressive and tensile failure strengths and secondary thermal creep of leading solid-breeder (Li/sub 2/O, Li/sub 4/SiO/sub 4/, and LiAlO/sub 2/) and multiplier (Be) materials is reviewed, porosity, grain size, and stress (for thermal creep). Because the data base is rather sparse in some areas, general properties of ceramics and metals are used to help guide the formulation of the correlations. The primary purpose of the data base summary and correlation development is to pave the way for stress analysis sensitivity studies. These studies will help determine which properties are important enough to structural lifetime and deformation assessments to require more data. 18 refs., 5 figs., 20 tabs.

The genesis and growth of Sandia National Laboratories, the nation's largest nuclear weapons lab, stands as a pertinent case study showing the oftentimes complex, but effective interaction of government, industry, and the growth of cooperative research. Originally a part of Los Alamos Scientific Laboratory under management by the University of California, Sandia traces its roots to Z Division, an ordnance-engineering arm located at Sandia Base on the desert outskirts of Albuquerque, New Mexico, in September 1945. For Sandia National Laboratories, the early postwar years/emdash/rather than representing a transformation to peacetime/emdash/were characterized by a continued mobilization of engineering and science in the name of national readiness.

This report presents a method for calculating the J/sub C/, H/sub C/, T/sub C/ surface for Type II Superconductors. The method requires that one knows T/sub C/ at zero current and field, H/sub c2/ at zero current and temperature, and J/sub c/ at at least one temperature and field. The theory presented in this report agrees with the measured data quite well over virtually the entire J/sub c/, H/sub c/, T/sub c/ surface given the value of J/sub c/ versus H at one or two temperatures. This report presents calculated and measured values of J/sub c/ versus T and B for niobium titanium, niobium zirconium, niobium tin, niobium titanium tin, niobium tantalum tin, vanadium zirconium hafnium, and vanadium gallium. Good agreement of theory with measured data was obtained for commercial niobium titanium and niobium tin. 76 refs., 26 figs., 6 tabs.

The PISCES plasma surface interaction facility at UCLA generates plasmas with characteristics similar to those found in the edge plasmas of tokamaks. Steady state magnetized plasmas produced by this device are used to study plasma-wall interaction phenomena which are relevant to tokamak devices. We report here progress on some detailed investigations of the presheath region that extends from a wall surface into these /open quotes/simulated tokamak/close quotes/ edge plasma discharges along magnetic field lines.

In these lectures, my aim is to present an up-to-date status report on the standard model and some key tests of electroweak unification. Within that context, I also discuss how and where hints of new physics may emerge. To accomplish those goals, I have organized my presentation as follows: I discuss the standard model parameters with particular emphasis on the gauge coupling constants and vector boson masses. Examples of new physics appendages are also briefly commented on. In addition, because these lectures are intended for students and thus somewhat pedagogical, I have included an appendix on dimensional regularization and a simple computational example that employs that technique. Next, I focus on weak charged current phenomenology. Precision tests of the standard model are described and up-to-date values for the Cabibbo-Kobayashi-Maskawa (CKM) mixing matrix parameters are presented. Constraints implied by those tests for a 4th generation, supersymmetry, extra Z/prime/ bosons, and compositeness are also discussed. I discuss weak neutral current phenomenology and the extraction of sin/sup 2/ /theta//sub W/ from experiment. The results presented there are based on a recently completed global analysis of all existing data. I have chosen to concentrate that discussion on radiative corrections, the effect of a heavy …

We review the present state of knowledge of the mixing of quark flavors under weak interactions and the associated explanation of CP violation inherent in the single nontrivial phase present in the three-generation mixing matrix. In this context we present the phenomenological basis for the increasing possibility that large CP violation asymmetries can be experimentally observed in the B meson system. 39 refs., 11 figs.,

A statistical analysis of spatial patterns of 1980 US urban total mortality (all causes) was performed, evaluating demographic, socioeconomic and air pollution factors as predictors. Specific mortality predictors included cigarette smoking, drinking water hardness, heating fuel use, and 1978-1982 annual concentrations of the following air pollutants: ozone, carbon monoxide, sulfate aerosol, particulate concentrations of lead, iron, cadmium, manganese, vanadium, as well as total and fine particle mass concentrations from the inhalable particulate network (dichotomous samplers). In addition, estimates of sulfur dioxide, oxides of nitrogen, and sulfate aerosol were made for each city using the ASTRAP long-range transport diffusion model, and entered into the analysis as independent variables. Because the number of cities with valid air quality and water hardness data varied considerably by pollutant, it was necessary to consider several different data sets, ranging from 48 to 952 cities. The relatively strong associations (ca. 5--10%) shown for 1980 pollution with 1980 total mortality are generally not confirmed by independent studies, for example, in Europe. In addition, the US studies did not find those pollutants with known adverse health effects at the concentrations in question (such as ozone or CO) to be associated with mortality. The question of causality vs. circumstantial …

Sandia National Laboratories, the nation's nuclear ordnance laboratory, is operated on a no-profit, no-fee basis by ATandT Technologies, Inc., as a prime contractor for the Department of Energy. This unique arrangement began in 1949 when President Harry Truman personally requested that ATandT assume management of the nuclear weapons laboratory as a service in the national interest. The story of how this unusual relationship came about makes for an interesting chapter in the annals of US legal and institutional history. This report describes the historical background, political negotiations, and prime contract provisos that established the legal framework for the Labs.