We report the results of variational calculations of elastic electron scattering by tetrafluoroethene, C{sub 2}F{sub 4}, with incident electron energies ranging from 0.5 to 20 eV, using the complex Kohn method and effective core potentials. These are the first fully calculations to reproduce experimental angular differential cross sections at energies below 10 eV. Low-energy electron scattering by C{sub 2}F{sub 4} is sensitive to the inclusion of electronic correlation and target-distortion effects. We therefore present results that describe the dynamic polarization of the target by the incident electron. The calculated cross sections are compared with recent experimental measurements.

The intermediate valence compounds Yb{sub 2}M{sub 3}Ga{sub 9} (M = Rh, Ir) exhibit an anisotropic magnetic susceptibility. We report measurements of the temperature dependence of the 4f occupation number, n{sub f}(T), for Yb{sub 2}M{sub 3}Ga{sub 9} as well as the magnetic inelastic neutron scattering spectrum S{sub mag}({Delta}E) at 12 and 300 K for Yb{sub 2}Rh{sub 3}Ga{sub 9}. Both n{sub f}(T) and S{sub mag}({Delta}E) were calculated for the Anderson impurity model with crystal field terms within an approach based on the non-crossing approximation. These results corroborate the importance of crystal field effects in these materials; they also suggest that Anderson lattice effects are important to the physics of Yb{sub 2}M{sub 3}Ga{sub 9}.

A fusion power plant is described that utilizes a new version of the tandem mirror device including spinning liquid walls. The magnetic configuration is evaluated with an axisymmetric equilibrium code predicting an average beta of 60%. The geometry allows a flowing molten salt, (flibe-Li{sub 2}BeF{sub 4}), which protects the walls and structures from damage arising from neutrons and plasma particles. The free surface between the liquid and the burning plasma is heated by bremsstrahlung radiation, line radiation, and by neutrons. The temperature of the free surface of the liquid is calculated, and then the evaporation rate is estimated from vapor-pressure data. The allowed impurity concentration in the burning plasma is taken as 1% fluorine, which gives a 17% reduction in the fusion power owing to D/T fuel dilution, with F line-radiation causing minor power degradation. The end leakage power density of 0.6 MW/m{sup 2} is readily handled by liquid jets. The tritium breeding is adequate with natural lithium. A number of problem areas are identified that need further study to make the design more self-consistent and workable; however, the simple geometry and the use of liquid walls promise the cost of power competitive with that from fission and coal.

CO{sub 2}-fertilization affects plant growth, which modifies surface physical properties, altering the surface albedo, and fluxes of sensible and latent heat. We investigate how such CO{sub 2}-fertilization effects on vegetation and surface properties would affect the climate system. Using a global three-dimensional climate-carbon model that simulates vegetation dynamics, we compare two multi-century simulations: a ''Control'' simulation with no emissions, and a ''Physiol-noGHG'' simulation where physiological changes occur as a result of prescribed CO{sub 2} emissions, but where CO{sub 2}-induced greenhouse warming is not included. In our simulations, CO{sub 2}-fertilization produces warming; we obtain an annual- and global-mean warming of about 0.65 K (and land-only warming of 1.4 K) after 430 years. This century-scale warming is mostly due to a decreased surface albedo associated with the expansion of the Northern Hemisphere boreal forests. On decadal time scales, the CO{sub 2} uptake by afforestation should produce a cooling effect that exceeds this albedo-based warming; but if the forests remain in place, the CO{sub 2}-enhanced-greenhouse effect would diminish as the ocean equilibrates with the atmosphere, whereas the albedo effect would persist. Thus, on century time scales, there is the prospect for net warming from CO{sub 2}-fertilization of the land biosphere. Further study is …

We present a novel method for computing cache-oblivious layouts of large meshes that improve the performance of interactive visualization and geometric processing algorithms. Given that the mesh is accessed in a reasonably coherent manner, we assume no particular data access patterns or cache parameters of the memory hierarchy involved in the computation. Furthermore, our formulation extends directly to computing layouts of multi-resolution and bounding volume hierarchies of large meshes. We develop a simple and practical cache-oblivious metric for estimating cache misses. Computing a coherent mesh layout is reduced to a combinatorial optimization problem. We designed and implemented an out-of-core multilevel minimization algorithm and tested its performance on unstructured meshes composed of tens to hundreds of millions of triangles. Our layouts can significantly reduce the number of cache misses. We have observed 2-20 times speedups in view-dependent rendering, collision detection, and isocontour extraction without any modification of the algorithms or runtime applications.

Article on the characterization of room-temperature ionic liquids by the Abraham model with cation-specific and anion-specific equation coefficients.

The COBRA-IE computer code is a thermal-hydraulic subchannel analysis program capable of simulating phenomena present in both PWRs and BWRs. As part of ongoing COBRA-IE assessment efforts, the code has been evaluated against experimental data from the NUPEC BWR Full-Size Fine-Mesh Bundle Tests (BFBT). The BFBT experiments utilized an 8 x 8 rod bundle to simulate BWR operating conditions and power profiles, providing an excellent database for investigation of the capabilities of the code. Benchmarks performed included steady-state and transient void distribution, single-phase and two-phase pressure drop, and steady-state and transient critical power measurements. COBRA-IE effectively captured the trends seen in the experimental data with acceptable prediction error. Future sensitivity studies are planned to investigate the effects of enabling and/or modifying optional code models dealing with void drift, turbulent mixing, rewetting, and CHF.

Atmospheric testing of nuclear weapons during the 1950s and early 1960s doubled the level of radiocarbon ({sup 14}C) in the atmosphere. From the peak in 1963, the level of {sup 14}CO{sub 2} has decreased exponentially with a mean life of about 16 years, not due to radioactive decay, but due to mixing with large marine and terrestrial carbon reservoirs. Since radiocarbon is incorporated into all living things, the bomb-pulse is an isotopic chronometer of the past half century. The absence of bomb radiocarbon in skeletonized human remains generally indicates a date of death before 1950. Comparison of the radiocarbon values with the post 1950 bomb-curve may also help elucidate when in the post 1950 era, the individual was still alive. Such interpretation however, must consider the age at death of the individual and the type of tissue sampled.

DElight is a simulation engine for daylight and electric lighting system analysis in buildings. DElight calculates interior illuminance levels from daylight, and the subsequent contribution required from electric lighting to meet a desired interior illuminance. DElight has been specifically designed to integrate with building thermal simulation tools. This paper updates the DElight capability set, the status of integration into the simulation tool EnergyPlus, and describes a sample analysis of a simple model from the user perspective.

We have developed CaO coatings that are applied by a thermal and chemical vapor deposition process. Several experiments were conducted to study how the deposition of Ca on a V-4Cr-4Ti substrate alloy is affected by variations in process temperature and time, specimen location, and surface preparation and pretreatment. Results showed that thick adherent coatings can be fabricated by thermal/chemical vapor deposition, especially if a double Ca treatment is applied. Extensive microstructural analysis of the coatings showed almost 100% CaO over a coating thickness of 20-30 {micro}m; electrical resistance (measured by the two-probe method) of the coatings was at least two orders of magnitude higher than the minimum required for blanket application. The results obtained in this study indicate that CaO is a viable coating for V-Li advanced blankets, but that significant additional effort is needed, especially from the standpoint of structure/composition relationship to its electrical resistance and the coating stability in a flowing Li environment. Furthermore, resistance must be measured in situ in Li to simultaneously evaluate coating integrity, resistance, and Li compatibility.

The objective of this paper is to introduce the process and philosophies used to develop LLNL methodology for performing nonnuclear safety bases. Our former approach needed revision in order to implement the new Work Smart Standard (WSS), 'Safety Basis Requirements for Nonnuclear Facilities at Lawrence Livermore National Laboratory Site Specific Standard' (UCRL-ID-150214), approved in 2003 and revised January, 2004. This work relates directly to the following workshop theme: 'Improvements in Chemical, Biological, and Non-nuclear Safety analysis.' A requirements document, Environmental Safety and Health Manual, Document 3.1 provides safety bases methodology 'how-to' for LLNL personnel. This methodology document had to undergo a major revision, and essentially was completely re-written, since the nonnuclear requirements underwent a major change due to the new standard. The new methodology was based on a graded approach respective to risk level for each hazard type and facility classification. The development process included input from a cross-section of representatives of LLNL organizations at every step in the process. The initial methodology was tested in a pilot project that resulted in completed safety basis analyses and documentation for a major facility at LLNL. Feedback from the pilot was used to refine the methodology. The new methodology promotes a graded …

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NASA's recent CRYSTAL-FACE field experiment focused on anvil cirrus clouds, an important but poorly understood element of our climate system. Data obtained include the first comprehensive measurements of aerosols and cloud particles throughout the atmospheric column during the evolution of multiple deep convective storm systems. Coupling these new measurements with detailed cloud simulations that resolve the size distributions of aerosols and cloud particles, we find several lines of evidence that most anvil crystals form on mid-tropospheric rather than boundary layer aerosols. This result defies conventional wisdom and indicates that distant pollution sources may impact anvil clouds more than local sources.

In this talk I summarize the status of exotic mesons, including both theoretical expectations and experimental candidates. The current experimental candidates are ''spin-parity exotics'', since these are most often considered possible hybrid mesons, the theoretical discussion will be mainly concerned with hybrids. The exotic meson candidates discussed are the surprisingly light {pi}{sub 1} (1400) and {pi}{sub 1} (1600).

Heulandite is a common rock-forming zeolite that exhibits wide solid solution of extra framework cations, presumably due to ready ion exchange with aqueous solutions. In order to provide a quantitative basis for interpreting and predicting the distribution of aqueous species between heulandite and aqueous solutions, ion exchange equilibrium between heulandite and aqueous solutions with respect to the binary cation pairs Ca{sup 2+} - K{sup +}, Ca{sup 2+} - Na{sup +}, K{sup +} - Na{sup +}, K{sup +} - Sr{sup 2+}, Na{sup +} - Sr{sup 2+}, and Ca{sup 2+} - Sr{sup 2+} was investigated. Homoionic Ca-, K-, and Na-heulandites prepared from natural heulandite were equilibrated with 0.1 N Cl{sup -} solutions containing various proportions of the cations in a given binary pair at 55 and 85 C to define isotherms describing partitioning of the cations over a wide range of heulandite and solution composition with respect to the cations in each pair. In general, the experiments equilibrated rapidly, within 11-15 weeks at 55 C and 3-4 weeks at 85 C. The exception was the Ca{sup 2+} - Sr{sup 2+} binary exchange, which did not equilibrate even after 3 months at 55 C and 4 weeks at 85 C. Slow exchange of …

A Sn-25 at.% Li alloy has been fabricated by starting with pure Sn and Li. The alloy was cast into various shapes and sent to researchers in several organizations in the United States and abroad for property measurements. The fabrication procedure involved gradual addition of Li from a separate vessel into a vessel that contained Sn; continuous stirring of the mixture during Li addition increased the Li content of the alloy gradually from 0 to the final value of 25 at.%. The melting temperature of the alloy was 334 C; its density was 6.36 g/cm{sup 3}. Results are presented on microstructure, chemical composition, phase distribution, and microhardness of the alloy. Several experiments were conducted to evaluate the chemical reactivity of the alloy with air, water, and steam. Results showed that the alloy undergoes catastrophic oxidation when T >250 C in air and develops an oxide scale in water at temperatures up to 95 C. Exposure in low-pressure steam at 200 C caused significant swelling and cracking of the alloy.

The authors report preparation procedures for some lithium and barium titanate compounds. The procedures utilize inexpensive, commercial TiCl{sub 4} in an aqueous HCl solution. The main preparation steps consist of chloride elimination by distillation with nitric acid, addition of hydroxides of Li (or Ba), evaporation of sols to dry powders, and thermal treatment to titanates. Thermal and X-ray analyses indicate that the formation temperatures are lower than the corresponding temperatures necessary for conventional solid-state reactions. These temperatures can be further decreased by addition of ascorbic acid during formation of Ti nitrate sols. Spherical powders (with particle diameters of < 100 {micro}m) are obtained by solvent extraction of water from sol drops emulsified in 2-ethylheksanol-1. Final correction of the composition of the spherical powders is carried out by an impregnation process.

Scientists from the Lawrence Berkeley National Laboratory (Berkeley Lab) have generated 300-femtosecond pulses of bend-magnet synchrotron radiation at the Advanced Light Source (ALS) with the aid of a laser ''time-slicing'' technique. This technique allows an ultrashort portion of an electron bunch in the ALS storage ring to be spatially displaced in such a way that the synchrotron radiation from the displaced portion can then be collected separately. Their proof-of-principle experiment demonstrates that this technique is a viable one for producing ultra-short pulses of x-rays. An ALS bend-magnet beamline is already under construction that will be dedicated to time-resolved x-ray diffraction, EXAFS, and other techniques capable of probing the long-range and local structure of matter on a femtosecond time scale. A proposed undulator beamline based on the same technique would further enhance the flux and brightness by orders of magnitude.

In an ongoing project to relate surface hydrothermal alteration to structurally controlled geothermal aquifers, we mapped a 16 km swath of the eastern front of the Stillwater Range using Hyperspectral fault and mineral mapping techniques. The Dixie Valley Fault system produces a large fractured aquifer heating Pleistocene aged groundwater to a temperature of 285 C at 5-6 km. Periodically over the last several thousand years, seismic events have pushed these heated fluids to the surface, leaving a rich history of hydrothermal alteration in the Stillwater Mountains. At Dixie Hot Springs, the potentiometric surface of the aquifer intersects the surface, and 75 C waters flow into the valley. We find a high concentration of alunite, kaolinite, and dickite on the exposed fault surface directly adjacent to a series of active fumaroles on the range front fault. This assemblage of minerals implies interaction with water in excess of 200 C. Field spectra support the location of the high temperature mineralization. Fault mapping using a Digital Elevation Model in combination with mineral lineation and field studies shows that complex fault interactions in this region are improving permeability in the region leading to unconfined fluid flow to the surface. Seismic studies conducted 10 km …

This contribution is a brief review of the status of hybrid baryons, which are hypothetical baryons that incorporate a gluonic excitation. We first summarize the status of hybrid mesons, since this closely related topic has seen considerable recent activity with the identification of two exotic candidates. Next we review theoretical expectations for the masses and quantum numbers of hybrid baryons, which have come from studies of the bag model, QCD sum rules and the flux tube model. Finally hybrid baryon experiment is discussed, including suggestions for experimenters at COSY.

IKNO (Innovation and KNOwledge) is a proposal for a multi-user facility based on an electron storage ring optimized for the generation of coherent synchrotron radiation (CSR) in the terahertz frequency range, and of broadband incoherent synchrotron radiation (SR) ranging from the IR to the VUV. IKNO can be operated in an ultra-stable CSR mode with photon flux in the terahertz frequency region up to nine orders of magnitude higher than in existing 3rd generation light sources. Simultaneously to the CSR operation, broadband incoherent SR up to VUV frequencies is available at the beamline ports. The main characteristics of the IKNO storage and its performance in terms of CSR and incoherent SR are described in this paper. The proposed location for the infrastructure facility is in Sardinia, Italy.

The objective of this paper is to introduce the process and philosophies used to implement the new Work Smart Standard (WSS), ''Safety Basis Requirements for Nonnuclear Facilities at Lawrence Livermore National Laboratory Site Specific Standard'' (UCRL-ID-150214), approved in 2003 and revised January, 2004. This work relates directly to the following workshop theme: ''Improvements in Chemical, Biological, and Non-nuclear Safety Analysis.'' This paper will describe the approach used to implement the new nonnuclear standard at LLNL and corresponding guidance manual: ES&H Manual, Document 3.1. The varied activities can be broken down into three main parts: (1) Implementation Plan Schedule. The Implementation Plan includes the due dates for revising nonnuclear facility safety analysis documentation to meet the new standard. Implementation of the new methodology is being phased over a 4-year period. Each directorate was tasked to schedule the revision date for each of their nonnuclear facilities, using agreed upon priority-ranking criteria. (2) Program Infrastructure. This includes the development of training courses, procedures, a website and tools required to perform the work (i.e. Q List, de minimus list) or tools helpful to perform the work; such as a program to automate the classification of chemical inventories and establish maximum facility inventory limits (MFILs). …

Thin films of YBa{sub 2}Cu{sub 3}O{sub 7-x} (YBCO) were grown on MgO buffered metallic substrates by pulsed laser deposition (PLD). The MgO buffer films, which provide the initial biaxial texture, had been grown on polished Hastelloy C276 (HC) tapes using inclined substrate deposition (ISD). The ISD process is promising for the fabrication of coated superconductor wires because it produces biaxially textured template films on nontextured substrate at high deposition rates. Biaxially aligned MgO films were deposited at deposition rates of 20 to 100 {angstrom}/sec. The buffer films were deposited on these template films before ablation of the YBCO films by PLD. The microstructure was studied by scanning electron microscopy and atomic force microscopy. X-ray pole figure analysis and {phi}- and {omega}-scans were used for texture characterization. Good in- and out-of-plane textures were observed on the ISD MgO films ({approx}1.5 {micro}m thick). The full width at half maximums were 9.2{sup o} for the MgO (002) {phi}-scan and 5.4{sup o} for the {omega}-scan. Cube-on-cube epitaxial growth of yttria-stabilized zirconia (YSZ) and ceria (CeO{sub 2}) films on the ISD MgO films was also achieved by PLD. A superconducting critical temperature of 90 K, with a sharp transition, and transport critical current density of …