The spatial arrangement of sodium cations for a series of sodium phosphate glasses, xNa{sub 2}O(100-x)P{sub 2}O{sub 5} (x<55), were investigated using {sup 23}Na spin-echo NMR spectroscopy. The spin-echo decay rate is a function of the Na-Na homonuclear dipolar coupling and is related to the spatial proximity of neighboring Na nuclei. The spin-echo decay rate in these sodium phosphate glasses increases non-linearly with higher sodium number density, and thus provides a measure of the Na-Na extended range order. The results of these {sup 23}Na NMR experiments are discussed within the context of several structural models, including a decimated crystal lattice model, cubic dilation lattice model, a hard sphere (HS) random distribution model and a pair-wise cluster hard sphere model. While the experimental {sup 23}Na spin-echo M{sub 2} are described adequately by both the decimated lattice and the random HS model, it is demonstrated that the slight non-linear behavior of M{sub 2} as a function of sodium number density is more correctly described by the random distribution in the HS model. At low sodium number densities the experimental M{sub 2} is inconsistent with models incorporating Na-Na clustering. The ability to distinguish between Na-Na clusters and non-clustered distributions becomes more difficult at higher sodium concentrations.
Lodestar has been an active participant in the low power Collective Thomson Scattering (CTS) diagnostic at TFTR in collaboration with MIT. Extensive studies were conducted regarding the use of gyrotron scattering as a low cost diagnostic for both energetic ions and alpha particles on TFTR. The numerical scattering code has been improved and compared with similar code developed at JET. The authors have participated and assisted in the CTS experiments through onsite visits and have successfully performed most of the data analysis tasks remotely. Through their analysis on the initial data base accumulated, they are able to understand qualitatively the general features of the anomalous large scattered signal, have proposed an explanation for its generation mechanism, and have suggested a potential new use of CTS as an edge diagnostic.
Statistical concepts, methods, and tools are often used in the implementation of statistical thinking. Unfortunately, statistical tools are all too often misused by not applying them in the context of statistical thinking that focuses on processes, variation, and data. The consequences of this misuse may be ''data torturing'' or going beyond reasonable interpretation of the facts due to a misunderstanding of the processes creating the data or the misinterpretation of variability in the data. In the hope of averting future misuse and data torturing, examples are provided where the application of common statistical tools, in the absence of statistical thinking, provides deceptive results by not adequately representing the underlying process and variability. For each of the examples, a discussion is provided on how applying the concepts of statistical thinking may have prevented the data torturing. The lessons learned from these examples will provide an increased awareness of the potential for many statistical methods to mislead and a better understanding of how statistical thinking broadens and increases the effectiveness of statistical tools.
This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) Program Development project at the Los Alamos National laboratory (LANL). The focus of this development has been an innovative beryllium air monitor for on-site' real-time continuous monitoring which overcomes limitations of the previous techniques for beryllium monitoring. A bench-top instrument has been set up and the performance of the instrument has been tested based on a solution aerosol. The sensitivity obtained with the instrument is sufficient to ensure workers can respond at airborne levels well below current exposure regulations. With this versatile, real-time monitor, worker exposure can be greatly reduced.
A GaN/AlGaN heterojunction bipolar transistor structure with Mg doping in the base and Si Doping in the emitter and collector regions was grown by Metal Organic Chemical Vapor Deposition in c-axis Al(2)O(3). Secondary Ion Mass Spectrometry measurements showed no increase in the O concentration (2-3x10(18) cm(-3)) in the AlGaN emitter and fairly low levels of C (~4-5x10(17) cm (-3)) throughout the structure. Due to the non-ohmic behavior of the base contact at room temperature, the current gain of large area (~90 um diameter) devices was <3. Increasing the device operating temperature led to higher ionization fractions of the mg acceptors in the base, and current gains of ~10 were obtained at 300 degree C.
We demonstrate that nonlinear optical fiber arrays can support stable soliton-like pulses with finite energy. The bound state that we have found is localized both in time and in a spatial domain in the direction perpendicular to the pulse propagation. We have proved the boundedness of the Hamiltonian function for the array. Finally, numerical studies support our analytical conclusions.
This demonstration project uses modern simulation techniques to illustrate the important technologies and design variables that an auto-designer would consider in production a high efficiency, low emissions vehicle. Simulation and modeling techniques use the idea of capturing the relationships between real components of the systems with mathematical equations. These equations are then solved on a computer to simulate the behavior or performance of the system under various conditions. In the current demonstration project, we focus on many variations of a hydrogen-powered vehicle.
In collaboration with the University of California at Irvine (UCI), we are working on a new technology that relies on the precise deposition of nanoliter molten-metal droplets that are targeted onto a substrate by electrostatic charging and deflection. By this way, three-dimensional (3D) structural materials can be manufactured microlayer by microlayer. Because the volume of the droplets are small, they rapidly solidify on impact, bringing forth a material component with fine grain structures which lead to enhanced material properties (e.g., strength). UCI is responsible for an experimental investigation of the manufacturing feasibility of this process. LLNL has unique expertise in the computational modeling of 3D heat transfer and solid mechanics and has the large-scale computer resources necessary to model this large system. Process modeling will help move this technology from the bench-top to an industrial process. Applications at LLNL include rapid prototyping of metal parts and manufacturing new alloys by co-jetting different metals.
Electrometallurgical treatment is a compact, inexpensive method that is being developed at Argonne National Laboratory to deal with spent nuclear fuel, primarily metallic and oxide fuels. In this method, metallic nuclear fuel constituents are electrorefined in a molten salt to separate uranium from the rest of the spent fuel. Oxide and other fuels are subjected to appropriate head end steps to convert them to metallic form prior to electrorefining. The treatment process generates two kinds of high-level waste--a metallic and a ceramic waste. Isolation of these wastes has been developed as an integral part of the process. The wastes arise directly from the electrorefiner, and waste streams do not contain large quantities of solvent or other process fluids. Consequently, waste volumes are small and waste isolation processes can be compact and rapid. This paper briefly summarizes waste isolation processes then describes development and characterization of the two waste forms in more detail.
The scope of this plan includes the Tank Waste Information Network System II (TWINS2) that contains the following major components: Tank Characterization Database (TCD), Tank Vapor Database (TVD), Data Source Access (DSA), automated Tank Characterization Report, Best-Basis Inventory Model (BBIM), and Tracker (corrective action tracking) function. The automated Tank Characterization Report application currently in development also will reside on-the TWINS system as will the BBIM. Critical inputs to TWINS occur from the following databases: Labcore and SACS. Output does not occur from TWINS to these two databases.
This Factory Acceptance Test Procedure (FAT) is for the Westinghouse 100 Ton Hydraulic Trailer. The trailer will be used for the removal of the 101-SY pump. This procedure includes: safety check and safety procedures; pre-operation check out; startup; leveling trailer; functional/proofload test; proofload testing; and rolling load test.
The authors have performed the reaction {sup 248}Cm({sup 4}He, {sup 3}He) using 98.5-MeV alpha particles from the IUCF cyclotron to populate high-j states in {sup 249}Cm. A tentative assignment of the K{sub 17/2} component of the 1/2{sup +}[880] Nilsson state has been made.
Deep level defects in silicon are identified by measuring the recombination lifetime as a function of the injection level. The basic models for recombination at deep and shallow centers is developed. The defect used for the theoretical model is the well-known interstitial Fe ion in silicon. Data are presented on silicon samples ranging in defect content from intentionally Fe-doped samples to an ultra-pure float-zone grown sample. These data are analyzed in terms of the injection-level spectroscopy model.
The family of ternary compounds of composition InxGa1-xAs are of considerable interest for thermophotovoltaic energy converters. The recombination lifetimes of the various compositions are critical to the successful application of these materials as efficient converters. Here we will describe experimental results on the composition. In0.53Ga0.47 that is lattice-matched to InP. We will also describe lifetime results on the compositions In0.68Ga0.32As, with bandgap of 0.60 eV to compositions In0.78Ga0.22As with a bandgap of 0.50 eV. Double heterostructure confinement devices have been made over a range of both n- and p-type doping. These results are preliminary, but the goal is to obtain the radiative and Auger recombination coefficients for the alloys in this composition range.
CQ Inc. and its project team members--Howard University, PrepTech Inc., Fossil Fuel Sciences, the United States Geological Survey (USGS), and industry advisors--are applying mature coal cleaning and scientific principles to the new purpose of removing potentially hazardous air pollutants from coal. The team uniquely combines mineral processing, chemical engineering, and geochemical expertise. This project meets more than 11 goals of the U.S. Department of Energy (DOE), the National Energy Strategy, and the 1993 Climate Change Action Plan. During this project: (1) Equations were developed to predict the concentration of trace elements in as-mined and cleaned coals. These equations, which address both conventional and advanced cleaning processes, can be used to increase the removal of hazardous air pollutant precursors (HAPs) by existing cleaning plants and to improve the design of new cleaning plants. (2) A promising chemical method of removing mercury and other HAPs was developed. At bench-scale, mercury reductions of over 50 percent were achieved on coal that had already been cleaned by froth flotation. The processing cost of this technology is projected to be less than $3.00 per ton ($3.30 per tonne). (3) Projections were made of the average trace element concentration in cleaning plant solid waste streams from individual states. Average concentrations were found to be highly variable. (4) A significantly improved understanding of how trace elements occur in coal was gained, primarily through work at the USGS during the first systematic development of semiquantitative data for mode of occurrence. In addition, significant improvement was made in the laboratory protocol for mode of occurrence determination. (5) Team members developed a high-quality trace element washability database. For example, the poorest mass balance closure for the uncrushed size and washability data for mercury on all four coals is 8.44 percent and the best is 0.46 percent. This indicates an extremely …
Using the CRYRing Facility in Stockholm Coupled with an MCP-CCD detector, and a differential stopping foil, we have determined dynamic parameters in the three-body dissociative recombination of H<sub>2</sub>O<sup>+</sup>. These include the distribution between the O(<sup>3</sup>P) and O(<sup>1</sup>D) channels, the distribution of H atom recoil energies in the O(<sup>3</sup>P) channel and the distribution of angles between the two departing H atoms.
I present some of the current ideas about a Very Large Hadron Collider [1] which could eventually extend the high energy frontier beyond that of the Large Hadron Collider (LHC) or any other machine seriously conceived at this time.
The authors describe the design and microfabrication of an extremely compact optical system as a key element in an integrated capillary-channel electrochromatograph with laser induced fluorescence detection. The optical design uses substrate-mode propagation within the fused silica substrate. The optical system includes a vertical cavity surface-emitting laser (VCSEL) array, two high performance microlenses and a commercial photodetector. The microlenses are multilevel diffractive optics patterned by electron beam lithography and etched by reactive ion etching in fused silica. Two generations of optical subsystems are described. The first generation design is integrated directly onto the capillary channel-containing substrate with a 6 mm separation between the VCSEL and photodetector. The second generation design separates the optical system onto its own module and the source to detector length is further compressed to 3.5 mm. The systems are designed for indirect fluorescence detection using infrared dyes. The first generation design has been tested with a 750 nm VCSEL exciting a 10{sup -4} M solution of CY-7 dye. The observed signal-to-noise ratio of better than 100:1 demonstrates that the background signal from scattered pump light is low despite the compact size of the optical system and meets the system sensitivity requirements.
InGaAsN alloys are a promising material for increasing the efficiency of multi-junction solar cells now used for satellite power systems. However, the growth of these dilute N containing alloys has been challenging with further improvements in material quality needed before the solar cell higher efficiencies are realized. Nitrogen/V ratios exceeding 0.981 resulted in lower N incorporation and poor surface morphologies. The growth rate was found to depend on not only the total group III transport for a fixed N/V ratio but also on the N/V ratio. Carbon tetrachloride and dimethylzinc were effective for p-type doping. Disilane was not an effective n-type dopant while SiCl4 did result in n-type material but only a narrow range of electron concentrations (2-5e17cm{sup -3}) were achieved.
Environmental surveillance of low-level radioactive particles in air requires a thorough understanding of low-level techniques and air sample collection media. High-volume air sampling for radioactive particles around Lawrence Livermore National Laboratory (LLNL) employs glass-fiber filters that are analyzed for gross alpha and gross beta activity and for specific isotopes. This study was conducted to determine the activities of radionuclides contained in blank glass-fiber filters. Data from this study provided a partial explanation of differences between current reported concentrations of radionuclides in air and those reported historically when cellulose filters were used in the LLNL monitoring effort.
A computational procedure for extracting substructure-by-substructure flexibility properties from global modal parameters is presented. The present procedure consists of two key features: an element-based direct flexibility method which uniquely determines the global flexibility without resorting to case-dependent redundancy selections; and, the projection of cinematically inadmissible modes that are contained in the iterated substructural matrices. The direct flexibility method is used as the basis of an inverse problem, whose goal is to determine substructural flexibilities given the global flexibility, geometrically-determined substructural rigid-body modes, and the local-to-global assembly operators. The resulting procedure, given accurate global flexibility, extracts the exact element-by-element substructural flexibilities for determinate structures. For indeterminate structures, the accuracy depends on the iteration tolerance limits. The procedure is illustrated using both simple and complex numerical examples, and appears to be effective for structural applications such as damage localization and finite element model reconciliation.
This report documents the determination that the in-basin activities at 105 K East (KE) and 105 K West (KW) on the Hanford Reservation associated with the fuel characterization program are classified as Hazard Category 3 (hazard analysis shows the potential for only significant localized consequences). Potential accident consequences, a description of significant activities around the site, and hazard identification and management were explored.
The quantum confined Stark effect was found to result in a strong quantum well width dependence of threshold current density in strained group-III nitride quantum well lasers. For an In{sub 0.2}Ga{sub 0.8}N/GaN structure with quantum well width in the neighborhood of 3.5nm, our analysis shows that the reduction in spontaneous emission loss by the electron-hole spatial separation outweighs the corresponding reduction in gain to produce a threshold current density minimum.
The measurement of liquid levels is the primary method of early leak detection in some underground waste storage tanks at Hanford, as well as for the detection of intrusion of liquids into the tanks. The gauges used for many years for this purpose are no longer available and are rapidly failing. After extensive evaluation and testing, the ENRAF Series 854 level gauge was selected as the primary instrument for monitoring waste surface levels. The material for the wire from which the displacer of the gauge is suspended was selected to be type 316 stainless steel based upon its excellent corrosion resistance in Hanford tank wastes. After approximately 10 weeks of service, the displacer attached to the gauge installed in tank 241-S-106 separated from the wire. It was determined that the wire failure was due to chloride ion stress corrosion cracking of the 316 wire. Radiation induced breakdown of the polyvinyl chloride (PVC) riser liners is suspected to be the source of the chloride ions. The task team proposed short-term and long-term actions. The short-term actions included evaluating the source of the chloride ions, while continuing to monitor liquid levels. One of the long-term actions is the selection of a wire material that is compatible with the PVC liner and the tank waste environment. This document describes the test plan for the selection of one material, from the list of candidate materials, that is the most suitable material for use in the combined environment of the PVC liner and the tank waste. The candidate materials to be tested are Hastelloy C-22, Pt-10% Rh, Pt-20% Rh, and Pt-20% Ir.
An analytic treatment of the one Higgs doublet, electroweak phase transition is given. The phase transition is first order, occurs by the nucleation of thin walled bubbles and completes at a temperature where the order parameter, {l_angle}{phi}{r_angle}{sub T} is significantly smaller than it is when the origin becomes absolutely unstable. The rate of anomalous baryon number violation is an exponentially function of {l_angle}{phi}{r_angle}{sub T}. In very minimal extensions of the standard model it is quite easy to increase {l_angle}{phi}{r_angle}{sub T} so that anomalous baryon number violation is suppressed after completion of the phase transition. Hence baryogenesis at the electroweak phase transition is tenable in minimal of the standard model. In some cases additional phase transitions are possible. For a light Higgs boson, when the top quark mass is sufficiently large, the state where the Higgs field has a vacuum expectation value {l_angle}{phi}{r_angle} = 246 GeV is not the true minimum of the Higgs potential. When this is the case, and when the top quark mass exceeds some critical value, thermal fluctuations in the early universe would have rendered the state {l_angle}{phi}{r_angle} = 246 GeV unstable. The requirement that the state {l_angle}{phi}{r_angle} = 246 GeV is sufficiently long lived constrains the masses of the Higgs boson and the top quark. Finally, we consider whether local phase transitions can be induced by heavy particles which act as seeds for deformations in the scalar field.
An analytic treatment of the one Higgs doublet, electroweak phase transition is given. The phase transition is first order, occurs by the nucleation of thin walled bubbles and completes at a temperature where the order parameter, {l angle}{phi}{r angle}{sub T} is significantly smaller than it is when the origin becomes absolutely unstable. The rate of anomalous baryon number violation is an exponentially function of {l angle}{phi}{r angle}{sub T}. In very minimal extensions of the standard model it is quite easy to increase {l angle}{phi}{r angle}{sub T} so that anomalous baryon number violation is suppressed after completion of the phase transition. Hence baryogenesis at the electroweak phase transition is tenable in minimal of the standard model. In some cases additional phase transitions are possible. For a light Higgs boson, when the top quark mass is sufficiently large, the state where the Higgs field has a vacuum expectation value {l angle}{phi}{r angle} = 246 GeV is not the true minimum of the Higgs potential. When this is the case, and when the top quark mass exceeds some critical value, thermal fluctuations in the early universe would have rendered the state {l angle}{phi}{r angle} = 246 GeV unstable. The requirement that the state {l angle}{phi}{r angle} = 246 GeV is sufficiently long lived constrains the masses of the Higgs boson and the top quark. Finally, we consider whether local phase transitions can be induced by heavy particles which act as seeds for deformations in the scalar field.
Technical guidance for performance assessment (PA) of low-level radioactive waste (LLRW) sites is currently dependent upon experimental retardation factors (K{sub D}'s) to predict radionuclide transport. Accurate predictions of waste transport or retardation will require mechanistic models of radionuclide sorption so as to be applicable to a wide range of soil/groundwater environments. To that end, we have investigated Cs{sup +}, Sr{sup +}, and Ba{sup 2+} sorption on several clay and Fe-oxide minerals. Relative metal binding strengths for montmorillonite clay decrease from Ba{sup 2+} to Sr{sup +}, which is similar to that sorption trend noticed for kaolinite. Molecular dynamics simulations for kaolinite suggest that Cs{sup +} is sorbed at aluminol (010) edge sites as an inner-sphere complex and weakly sorbed as an outer-sphere complex on (001) basal surfaces. Sorption is thought to occur on similar sites for smectite clays, however, the basal plane residual charge and its increased basal plane exposure should have a greater influence on metal sorption. On the other hand, phase transformation kinetics (e.g., ferrihydrite to goethite) is a very important control of metal sorption and resorption for Fe-oxides/hydroxides. These results provide a basis for understanding and predicting metal sorption on complex soil minerals.
Recent improvements in computer hardware and software for the acquisition, storage and analysis of series of spectra and images allow for a change in strategy for quantitative microanalysis. For example, in the area of X-ray microanalysis, whereas compositional analysis and elemental distributions have been traditionally performed using point microanalysis and simple intensity mapping from a ROI, respectively, the two tasks are now routinely performed simultaneously through X-ray spectrum-imaging, where full spectra are acquired from pixels in a two-dimensional array of points on the specimen. Commercially available software now allows for the acquisition and storage of such spectrum-images, perhaps comprising as much as 100 MBytes of data or more. A variety of post-acquisition processing tools are provided by the developer to allow the extraction of both X-ray intensity maps, with or without rudimentary background subtraction, or full spectra from pixels of interest. In order to maximize the extraction of information from these large data sets, a number of linear and nonlinear methods are currently being explored that identify statistically significant variations among the series of spectra without a priori assumptions about the content of the data set. Among these methods, linear multivariate statistical analysis (MSA) has a number of significant advantages, including its comprehensiveness, since all spectral variations distinct from the Poisson noise level are identified, and its broad applicability to a variety of microanalytical techniques.
This report describes an innovative technology, laser ablation-inductively couple plasma-mass spectrometry (LA-ICP-MS), operated in a mobile laboratory, to rapidly detect thorium 230 activity levels in soil samples. This technology was demonstrated on-site during November 1993 at the Gunnison, Colorado, UMTRA project site in support of their remediation effort. The LA-ICP-MS sampling and analysis technique was chosen because of the capability for rapid analysis, approximately three samples per hour, with minimal sample preparation.
In 1993, members of our team collaborated with Silicon Graphics to perform the first full-scale demonstration of the computational power of the SMP cluster supercomputer architecture. That demonstration involved the simulation of homogeneous, compressible turbulence on a uniform grid of a billion cells, using our PPM gas dynamics code. This computation was embarrassingly parallel, the ideal test case, and it achieved only 4.9 Gflop/s performance, slightly over half that achievable by this application on the most expensive supercomputers of that day. After four to five solid days of computation, when the prototype machine had to be dismantled, the simulation was only about 20% completed. Nevertheless, this computation gave us important new insights into compressible turbulence and also into a powerful new mode of cost-effective, commercially sustainable supercomputing [S]. In the intervening 6 years, the SMP cluster architecture has become a fundamental strategy for several large supercomputer centers in the US, including the DOE's ASCI centers at Los Alamos National Laboratory and at the Lawrence Livermore National Laboratory and the NSF's center NCSA at the University of Illinois. This SMP cluster architecture now underlies product offerings at the high-end of performance from SGI, IBM, and HP, among others. Nevertheless, despite many successes, it is our opinion that the computational science community is only now beginning to exploit the full promise of these new computing platforms. In this paper, we will briefly discuss two key architectural issues, vector computing and the flat multiprocessor architecture, which continue to drive spirited discussions among computational scientists, and then we will describe the hierarchical shared memory programming paradigm that we feel is best suited to the creative use of SMP cluster systems. Finally, we will give examples of recent large-scale simulations carried out by our team on these kinds of systems and point toward the still …
Bigplate is an advanced explosive equation of state (EOS) test. It consists of a point detonator driving a large disc (100 mm radius) of explosive, which pushes a 0.5 mm thick copper or tantalum plate. The plate is observed by a five-beam Fabry-Perot interferometer, which has beams at 0, 10, 20,40 and 80 mm on the plate. A short Fabry gives the jump-off to high accuracy; a long Fabry runs out to I0-15 microsec. A detailed error analysis is given, with the final velocity measurements considered good to ±0.066 mm/microsec. Jump-offs are measured to 0.01-0.02 microsec. Spall is seen in all shots, which creates a time delay on both the first and second velocity plateaus. A 0.1 microsec delay in jump-off of unknown origin is also seen at 80 mm. In order of decreasing explosive ideality, the explosives tired have been LX-14, LX-04 and LX-17. To partially negate the time delays, the data and code runs are overlaid at each radial position between the first and second plateaus. Traditional JWL's model LX-14 and LX-04 within accuracy, but not so for LX-17. The spall may be partly modeled using the pmin model but high resolution zoning is required. At longer times, spall does not appear to affect the explosive energetics. Because it includes diagonal zone crossing, Bigplate occupies a location between simple plate and cylinder tests and truly complex geometries. Hence, an EOS that fails Bigplate is not likely to move on to more complex issues. Bigplate is an excellent test bed for radically new EOS's, and the initial LX-17 runs done with Equilibrium and KINETIC CHEETAH are promising.
As a way to lower the cost of plastic scintillation detectors, commercially available polystyrene pellets have been used in the production of scintillating materials that can be extruded into different profiles. The selection of the raw materials is discussed. Two techniques to add wavelength shifting dopants to polystyrene pellets and to extrude plastic scintillating strips are described. Data on light yield and transmittance measurements are presented.
The voltage or electric potential difference across the terminals of a cell when no current is drawn from it. The emf of a cell is the sum of the electric potential differences (PDs) produced by a separation of charges (electrons or ions) that can occur at each phase boundary (or interface) in the cell. The magnitude of each PD depends on the chemical nature of the two contacting phases. Thus, at the interface between two different metals, some electrons will have moved from the metal with a higher free energy of electrons to the metal with a lower free energy of electrons. The resultant charge separation will produce a PD (just as charge separation produces a voltage across a capacitor) that, at equilibrium, exactly opposes further electron flow. Similarly, PDs can be produced when electrons partition across a metal/solution interface or metal/solid interface, and when ions partition across a solution/membrane/solution interface.
This report presents preliminary considerations for recovering and converting weapon plutonium from various US weapon forms into feed material for fabrication of reactor fuel elements. An ongoing DOE study addresses the disposition of excess weapon plutonium through its use as fuel for nuclear power reactors and subsequent disposal as spent fuel. The spent fuel would have characteristics similar to those of commercial power spent fuel and could be similarly disposed of in a geologic repository.
Tables in this document present data from routine environmental monitoring and surveillance programs at the Savannah River Site. An attempt has been made to include all available data from environmental research programs. The first section of the book is a collection of maps of radiological and non radiological sampling locations. Also included are a list of the media sampled, along with sample sizes and representative aliquots; the minimum detectable concentrations for gamma analysis of soil, food, fish and wildlife, and vegetation samples; and a list of the minimum detectable concentrations for Environmental Monitoring Section radiological analyses.
The mission at the Savannah River Site has changed from producing nuclear weapons materials for national defense to managing the waste it has generated, restoring the environment, and enhancing industrial development in and around the site. But no matter what the site`s mission is, it will continue to maintain its comprehensive environmental monitoring and surveillance program. In 1994, effluent monitoring and environmental surveillance were conducted within a 30,000-square-mile area in and around SRS that includes neighboring cities, towns, and counties in Georgia and South Carolina and extends up to 100 miles from the site. Thousands of samples of air, surface water, groundwater, foodstuffs, drinking water, wildlife, rainwater, soil, sediment, and vegetation were collected and analyzed for radioactive and nonradioactive contaminants.
Enzymes have enormous potential for reducing energy requirements and environmental problems in the chemicals and pharmaceutical industries. The explosion of tools that has come out of molecular biology during the last 20 years has made it possible to evolve enzymes for features never required in nature. Scientists can speed up the rate and channel the direction of evolution by controlling mutagenesis and the accompanying selection pressures. Darwinian evolution carried out in the test tube offers a unique opportunity for biotechnology: the ability to tailor enzymes for optimal performance in a wide range of applications. Thus it is possible, for example, to evolve enzymes that carry out reactions on nonnatural substrates or even to carry out reactions for which there is no counterpart in nature. Due to the vast size of the potential sequence space, however, explorations by directed evolution must be guided by sound principles and workable strategies. During the course of this group, this laboratory has continued to make significant progress in the evolution of industrial enzymes as well as in developing general methods for in vitro evolution.
Lockheed Martin Energy Systems, Inc. and Ferro Corporation (formerly W. R. Grace, the original CRADA partner) have collaborated on an effort to develop techniques and processes for the cost-effective machining of ceramic components. The purpose of this effort was to develop a machining model, and grinding equipment machines and techniques for fabricating precision ceramic components. This project was designed to support Department of Energy (DOE) technical needs in manufacturing hard materials as well as enabling U.S. industry to maintain a position of leadership in the production of precision grinding machines and the machining of structural ceramic components.
This paper provides a brief review of experimental techniques for producing dynamic isentropic compression of samples to pressures of several hundred GPa. Traditional gun launch techniques include use of buffer plates, such as fused silica, that exhibit negative curvature to their stress-strain response and graded-density impactors. Graded-density impactors have been used to study isentropic compression of specimens to pressures exceeding 2 Mbar on high-impedance materials. A recent development includes the use of the Sandia Z Accelerator to produce magnetic compression in planar specimens to pressures of a few hundred kbar over time scales of 100 ns. These techniques have been successfully applied to isentropic compression of iron to 300 kbar and copper to 130 kbar. The iron results indicate that it is possible to study the polymorphic phase change that occurs at 130 kbar and also the kinetic properties of the transformation. The copper results indicate that with further improvements in progress it should be possible to measure continuous isentropic compression curves in materials of interest to pressures exceeding 1 Mbar. The Z accelerator is limited to peak currents of about 20 MA. By reconfiguring the anode-cathode geometry it should be possible to obtain constant current density and thus driving pressure to about 3 Mbar. The next generation accelerator referred to as ZX, which is being proposed will have the capability to generate currents to 50 MA and resulting peak pressures to 15 Mbar.
This report examines intellectual property right in pharmaceuticals in a particular context, namely, medicinal products and processes derived from the biodiversity resources of areas inhabited by indigenous peoples. This report discusses the international law regarding intellectual property rights in traditional knowledge and the American laws regarding traditional knowledge.
Physical Optics Corporation (POC) investigated the development of an optical data storage system built around a current well-engineered high-speed optical disk system with an innovative diffraction-free micro-optical element to produce a beam {approximately}250 nm wide with {approximately}4-5 mm depth of focus, allowing the system to address data at {approximately}100 Mbits/second and to store it 100 to 1,000 times more densely ({approximately}10 Gbit/in.{sup 2}) than in present systems. In Phase 1 of this project POC completed a thorough feasibility study by system design and analysis, successfully demonstrated fabrication of the key components, and conducted a proof-of-principle experimental demonstration. Specifically, production of a subwavelength ({approximately}380 nm) large depth of focus ({approximately}4-5 mm) addressing beam was demonstrated by fabricating a special microdiffractive optical element and recording this beam on a standard optical recording disk coated with a photopolymer material.
The generation of suitable simulation grids for heterogeneous media and specific discretization issues that arise. Streamlines and equipotentials are used to define our base grids. Since streamlines are concentrated in high velocity regions they provide a natural means of clustering fine grid cells in crucial flow regions. For complex configurations and particularly for strongly heterogeneous regions the resulting grid cells can become very distorted due to extremely high curvatures. Two types of cell centered formulation are examined together with a cell vertex-point distributed scheme. Important distinctions are found for highly distorted cells. The new grids are tested for accuracy in terms of critical breakthrough parameters and it is shown that a much higher level of grid resolution is required by conventional simulators in order to achieve results that are comparable with those computed on relatively coarse streamline-potential grids.
In the aftermath of the Cold War, the United States has begun addressing the environmental consequences of five decades of nuclear weapons production. In November 1989, DOE established the Office of Environmental Restoration and Waste Management (EM) as the central authority for cleaning up the DOE weapons complex legacy of pollution, for preventing further environmental contamination, and for instituting responsible environmental management. While performing its tasks, EM found that many aspects of its large and complex mission could not be achieved using existing science and technology or without incurring unreasonable costs, risks, or schedule impacts. Consequently, a process was developed to solicit needs from around the DOE complex and focus the science and technology resources of EM-50, the National Laboratories, private industry, and colleges and universities on those needs. This document describes those needs that the Hanford Site has identified as requiring additional science or technology to complete.
PEP's Standby Power System consists of the diesel generators, the generator control system, Rm 308 UPS, switchgear batteries, and the electrical equipment used to distribute this power. Due to the nature of the equipment and its use throughout general industry, the majority of the system falls within the CGI definition HNF-PRO-268. ''Control of Purchased Items and Services'' and HNF-PRO-1819, ''PHMC Engineering Requirements'' require that the critical characteristics of CGI-procured equipment be established in an engineering document prior to placing the order. HNF-5043 establishes these critical characteristics for the Standby Power System. Equipment will be added to the list as required to support future CGI procurements.
The general physical layout is: (1) There are a total of 9 slots, designated 1 through 9, from left to right; (2) Each slot is associated with a 96 pin Class 2 DIN 41612 (VME type) connector; (3) All even numbered slots are right handed (Connectors to the right of the card)., as would be found on a normal VME J1 backplane, these slots utilize standard DIN connectors; (4) All odd numbered slots are left handed. These slots utilize standard 96 pin Class 2 DIN 41612 connectors orientated with 180 degrees of rotation. Thus, the connector's Al position is associated with the lower right pad of the backplane for that particular connector. Likewise, the connector's C32 position is associated with the upper left pad of the backplane for that particular connector; (5) 5 layers (comp, gnd, pwr, gnd, sold); (6) .125-inch thick; and (7) Mechanical layout presented in drawing number 3823.113-MD-330044. Electrical characteristics are: (1) The backplane is routed as though it were a standard 9 slot VME J1 backplane, with 11 as the mater slot, as dermed in ANSI/IEEE 1014-1987 standard; (2) The presence of odd slots has no effect on backplane routing. At each and every slot, Al and the signal assigned Al by the VME standard is located in the upper left hand comer as viewed from the front of the backplane. Thus, the routing paths are the same as a standard VME J1 backplane; (3) Line impedances, terminations, bus grant and interrupt acknowledge jumper pins shall be the same as a standard VME J1 backplane, as dermed in the ANSI/IEEE 1014-1987 standard; and (4) The space between DIN connectors on the front of the backplane shall be kept clear. Any bus grant and interrupt acknowledge jumper pins shall be located on the rear of the backplane. …
LECO carbon analysis of plutonium metal and plutonium oxide at the Rocky Flats Plant generates several hundred kilograms of high silica residues each year. The plutonium in these residues is difficult and expensive to recover using production dissolution processes. A magnesium oxide (MgO) insert has been developed that significantly lowers the plutonium recovery costs without adversely affecting accuracy of the carbon analysis.
A recent DOE-Savannah River review of the results and data from the Late Washing Crossflow Fitter assessment identified the fate of biphenyl as a concern in the Late Washing material balance. The concern arose because after the late washing operation only about 40% of the biphenyl remained in the irradiated precipitate and analyses of the spent wash water stream did not account for the missing biphenyl [2]. This document summarizes the results of subsequent filtration studies on the behavior and fate of all known organic precipitate feed components including biphenyl. The study employed a statistically designed material balance across a laboratory crossflow fitter. Data from two separate experiments are presented here. Results of the first study indicated no statistically significant loss of biphenyl, diphenylmercury, 0-terphenyl, diphenylamine, or aniline. Results did indicate minor losses of phenylboric acid, M-terphenyl, P-terphenyl, and a significant production of phenol, believed to be due to the way in which the experiment was performed. A second experiment demonstrated no statistically significant lose of any of the organic compounds.
A recent DOE-Savannah River review of the results and data from the Late Washing Crossflow Fitter assessment identified the fate of biphenyl as a concern in the Late Washing material balance. The concern arose because after the late washing operation only about 40% of the biphenyl remained in the irradiated precipitate and analyses of the spent wash water stream did not account for the missing biphenyl [2]. This document summarizes the results of subsequent filtration studies on the behavior and fate of all known organic precipitate feed components including biphenyl. The study employed a statistically designed material balance across a laboratory crossflow fitter. Data from two separate experiments are presented here. Results of the first study indicated no statistically significant loss of biphenyl, diphenylmercury, 0-terphenyl, diphenylamine, or aniline. Results did indicate minor losses of phenylboric acid, M-terphenyl, P-terphenyl, and a significant production of phenol, believed to be due to the way in which the experiment was performed. A second experiment demonstrated no statistically significant lose of any of the organic compounds.
This paper presents the personal views of the author on the subject of the proposed Chemical Weapons Convention (CWC). She addresses here concerns about the national security issues which could result from ratification of this convention. She argues the convention alone is not likely to curtail production or availability of such items on the world market because of the relatively low cost. The treaty could thus put the country in a position less likely to protect itself, or adequately deal with such a threat.
Candidate immobilization forms for the disposal of surplus weapons-useable are being tested and characterized. The goal of the testing program was to provide sufficient data that, by August 1997, an informed selection of a single immobilization form could be made so that the form development and production R and D could be more narrowly focused. Two forms have been under consideration for the past two years: glass and ceramic. In August, 1997, the Department of Energy (DOE) selected ceramic for plutonium disposition, halting further work on the glass material. In this paper, we will briefly describe these two waste forms, then describe our characterization techniques and testing methods. The analytical methods used to characterize altered and unaltered samples are the same. A full suite of microscopic techniques is used. Techniques used include optical, scanning electron, and transmission electron microscopies. For both candidate immobilization forms, the analyses are used to characterize the material for the presence of crystalline phases and amorphous material. Crystalline materials, either in the untested immobilization form or in the alteration products from testing, are characterized with respect to morphology, crystal structure, and composition. The goal of these analyses is to provide data on critical issues such as Pu and neutron absorber volubility in the immobilization form, thermal stability, potential separation of absorber and Pu, and the long-term behavior of the materials. Results from these analyses will be discussed in the presentation. Testing methods include MCC-1 tests, product consistency tests (methods A and B), unsaturated ''drip'' tests, vapor hydration tests, single-pass flow-through tests, and pressurized unsaturated flow tests. Both candidate immobilization forms have very low dissolution rates; examples of typical test results will be reported.
This dialog allows you to filter your current search.
Each of the Collections listed note their name and the number of records that will be limited down to if you choose that option.
This dialog allows you to filter your current search.
Each of the Serial/Series Titles listed note their name and the number of records that will be limited down to if you choose that option.
The list can be sorted by name or the count.
This dialog allows you to filter your current search.
Each of the Resource Types listed note their name and the number of records that will be limited down to if you choose that option.
The list can be sorted by name or the count.
This dialog allows you to filter your current search.
Each of the World Regions listed note their name and the number of records that will be limited down to if you choose that option.
This dialog allows you to filter your current search.
Each of the Countries listed note their name and the number of records that will be limited down to if you choose that option.
This dialog allows you to filter your current search.
Each of the U.S. States listed note their name and the number of records that will be limited down to if you choose that option.
This dialog allows you to filter your current search.
Each of the Counties listed note their name and the number of records that will be limited down to if you choose that option.
This dialog allows you to filter your current search.
Each of the Years listed note their name and the number of records that will be limited down to if you choose that option.
The list can be sorted by name or the count.
This dialog allows you to filter your current search.
Each of the Months listed note their name and the number of records that will be limited down to if you choose that option.
The list can be sorted by name or the count.