Measurements of dielectric leakage, capacitance, electric strength, andd charge scattering phenomena were performed at the Kukla and Godiva III critical assemblies for tantalum and aluminum electrolytic, wax- and oilimpregnated paper, mylar, mica, and ceramic capacitors, and for mylar and Vitamin B-impregnated paper. Leakage data indicate that gamma induced conductivity in capacitor dielectric varies directly with gamma DELTA , where gamma is the gamma radiation rate and DELTA is 0.9 for mylar, 0.7 for Vitamin Q-impregnated paper, and approximately 1.0 for the other dielectrics. A small portion of the tantalum oxide conductivity induced by gamma radiation exhibited a recovery time of approximately 150 mu s. Transient capacitance changes due to radiation were non- existent within plus or minus 0.1% for mica and Vitamin Q capacitors. Transient charging of tantalum capacitors was noted during irradiation with no applied voltage. No drastic changes in electric strength were noted during irradiation of mylar and Vitamin Q-impregnated paper. Results are compared with a summary of data previously collected by others. The use of test data in parametric form as a tool for predicting transient radiation effects is discussed. (auth)

Boron nitride (BN) is a synthetic binary compound located between III and V group elements in the Periodic Table. However, its properties, in terms of polymorphism and mechanical characteristics, are rather close to those of carbon compared with other III-V compounds, such as gallium nitride. BN crystallizes into a layered or a tetrahedrally linked structure, like those of graphite and diamond, respectively, depending on the conditions of its preparation, especially the pressure applied. Such correspondence between BN and carbon readily can be understood from their isoelectronic structures [1, 2]. On the other hand, in contrast to graphite, layered BN is transparent and is an insulator. This material has attracted great interest because, similar to carbon, it exists in various polymorphic forms exhibiting very different properties; however, these forms do not correspond strictly to those of carbon. Crystallographically, BN is classified into four polymorphic forms: Hexagonal BN (h-BN) (Figure 1(b)); rhombohedral BN (r-BN); cubic BN (c-BN); and wurtzite BN (w-BN). BN does not occur in nature. In 1842, Balmain [3] obtained BN as a reaction product between molten boric oxide and potassium cyanide under atmospheric pressure. Thereafter, many methods for its synthesis were reported. h-BN and r-BN are formed under ambient …

The prospect of modeling across disparate length and time scales to achieve a predictive multiscale description of real materials properties has attracted widespread research interest in the last decade. To be sure, the challenges in such multiscale modeling are many, and in demanding cases, such as mechanical properties or dynamic phase transitions, multiple bridges extending from the atomic level all the way to the continuum level must be built. Although often overlooked in this process, one of the most fundamental and important problems in multiscale modeling is that of bridging the gap between first-principles quantum mechanics, from which true predictive power for real materials emanates, and the large-scale atomistic simulation of thousands or millions of atoms, which is usually essential to describe the complex atomic processes that link to higher length and time scales. For example, to model single-crystal plasticity at micron length scales via dislocation-dynamics simulations that evolve the detailed dislocation microstructure requires accurate large-scale atomistic information on the mobility and interaction of individual dislocations. Similarly, modeling the kinetics of structural phase transitions requires linking accurate large-scale atomistic information on nucleation processes with higher length and time scale growth processes.

Current practices within the oceanographic community have been reviewed with regard to the use of metrics to assess the realism of the upper-ocean circulation, ventilation processes diagnosed by time-evolving mixed layer depth and mode water formation, and eddy heat fluxes in large-scale fine resolution ocean model simulations. We have striven to understand the fidelity of these simulations in the context of their potential use in future fine-resolution coupled climate system studies. A variety of methodologies are used to assess the veracity of the numerical simulations. Sea surface height variability and the location of western boundary current paths from altimetry have been used routinely as basic indicators of fine-resolution model performance. Drifters and floats have also been used to provide pseudo-Eulerian measures of the mean and variability of surface and sub-surface flows, while statistical comparisons of observed and simulated means have been carried out using James tests. Probability density functions have been used to assess the Gaussian nature of the observed and simulated flows. Length and time scales have been calculated in both Eulerian and Lagrangian frameworks from altimetry and drifters, respectively. Concise measures of multiple model performance have been obtained from Taylor diagrams. The time-evolution of the mixed layer depth …

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The workshop titled, National Library of Medicine: Evidence-based Information At Your Fingertips, is a computer training class designed to meet the needs of nurses who require access to information on specific medical topics and on the adverse health effects of exposure to hazardous substances. The Specialized Information Services Division of the National Library of Medicine (NLM) is sponsoring this workshop for the National Black Nurses Association to increase the awareness of health professionals of the availability and value of the free NLM medical, environmental health, and toxicology databases.

In the past, the vast majority of nuclear physics calculations were carried out using nonrelativistic quantum mechanics. Relativistic effects were usually regarded as small corrections, primarily kinematic in origin. However, as understanding of hadronic matter has developed, and as high energy accelerators capable of probing hadronic systems to very high momenta become available, interest in relativistic methods has grown and theoretical techniques have matured. Until the early 1980's, most research was centered on methods for computing relativistic corrections to calculations which are essentially non-relativistic. The idea was to find corrections to lowest order in (v/c){sup 2}, where v is a typical particle velocity regarded as small compared to nuclear energies and masses. Recent work goes far beyond such expansion methods. Fully covariant approaches, in which the dynamics is closely connected to field theory, are now being developed.

Proceedings of the Environmental Health Information Partnership (EnHIP) Meeting March 25-26, 2010

A joint NREL, ORNL, and PNNL team conducted market analysis to help inform DOE/EERE's Weatherization and Intergovernmental Program planning and management decisions. This chapter presents the results of the market analysis for the Buildings sector.

To quantify metal natural attenuation processes in terms of environmental availability, sequential extraction experiments were carried out on subsurface soil samples impacted by a low pH, high sulfate, metals (Be, Ni, U, As) plume associated with the long-term operation of a coal plant at the Savannah River Site in South Carolina. Despite significant heterogeneity resulting both from natural and anthropogenic factors, sequential extraction results demonstrate that pH is a controlling factor in the prediction of the distribution of metal contaminants within the solid phases in soils at the site as well as the contaminant partitioning between the soil and the soil solution. Results for beryllium, the most mobile metal evaluated, exhibit increasing attenuation along the plume flow path which corresponds to an increasing plume pH. These laboratory- and field-scale studies provide mechanistic information regarding partitioning of metals to soils at the site (one of the major attenuation mechanisms for the metals at the field site). Subsequently, these data have been used in the definition of the contaminant source terms and contaminant transport factors in risk modeling for the site.

A number of carcinogenic heterocyclic amines (PhIP, MeIQx, and DiMeIQx) are produced from the condensation of creatinine, hexoses and amino acids during the cooking of meat (1). There are many variables that impact the production and subsequent ingestion of these compounds in our diet. Temperature, type of meat product, cooking method, doneness, and other factors affect the quantity of these carcinogens consumed by humans. Estimates of ingestion of these carcinogens are 1-20 ng/kg body weight per day (2). Human case control studies that correlate meat consumption from well-done cooking practices with cancer incidence indicate excess tumors for breast, colon, stomach, esophagus, and possibly prostate (3-5).

New airfoils have substantially increased the aerodynamic efficiency of wind turbines. It is clear that these new airfoils substantially increased energy output from wind turbines. Virtually all new blades built in this country today use these advanced airfoil designs.

The Sun's Joules is a CD-ROM that mixes interactive exercises, videos, photographs, and text to provide a comprehensive encyclopedia on renewable energy.

Thin-film photovoltaic (PV) cells are now doubling as rooftop shingles. PV shingles offer many advantages. The energy generated from a building's PV rooftop shingles can provide power both to the building and the utility's power grid.

DOE contributed markedly to the geothermal, oil, and gas industries through the development of the advanced polycrystalline diamond compact (PDC) drill bit. Diamond-cutter drill bits cut through tough rock quicker, reducing the cost of drilling for energy resources.

This long-distance solar car race provides a unique opportunity to increase America's awareness of a variety of important issues: renewable energy sources and technologies, environmentally clean energy options, improvements in transportation and opportunities in new, fast-growing energy-related businesses.

Power towers convert the thermal energy of the sun to electricity. They are large-scale power plants producing clean energy and suited for operation in sunny, semi-arid regions of the world.

As part of its energy management program, the National Park Service (NPS) has been actively promoting energy conservation and the greater use of renewable energy technologies such as photovoltaics (PV). PV is proving to be a very effective way to produce electricity in our parks.

The United States and Brazil are collaborating to bring electricity to some 5 million households in rural Brazil. Over the next decade, there is a potential to install approximately 500 megawatts (MW) of solar home systems and 1000 MW of community systems, bringing light to households, schools, and health clinics throughout rural Brazil.

Many energy efficiency and renewable energy technologies were featured at the 1996 Atlanta Olympics. Most of the projects that contributed to the Olympics continue to provide a meaningful demonstration and learning experience for the people of Atlanta.

Photovoltaics (PV) is a modern energy technology that makes use of semiconductor materials to convert sunlight directly to electricity. The idea of thin film technology is to produce truly low-cost PV devices by using pennies worth of active semiconductor materials.

A 3.5-megawatt valve-regulated lead-acid (VRLA) battery system installed at a lead recycling plant in California provides one hour of energy storage for both peak-shaving and uninterruptible power. It incorporates improvements in battery materials, manufacturing processes, and quality control.

The Solar Electric Generating System (SEGS) plants use parabolic-trough solar collectors to capture the sun's energy and convert it to heat. The SEGS plants range in capacity from 13.8 to 80 MW, and they were constructed to meet Southern California Edison Company's periods of peak power demand.

DOE research helped develop the large, untapped geothermal resource beneath the Salton Sea in California's Imperial Valley. The very hot brines under high pressure make them excellent for electric power production. The brines are very corrosive and contain high concentrations of dissolved silica. DOE worked with San Diego Gas and Electric Company to find a solution to the silica-scaling problem. This innovative brine treatment eliminated scaling and made possible the development of the Salton Sea geothermal resource.