Low cross section experiments to produce super-heavyelements have increased the demand for high intensity heavy ion beams atenergies of about 5 MeV/nucleon at the 88-Inch Cyclotron at the LawrenceBerkeley National Laboratory. Therefore, efforts are underway to increasethe overall ion beam transmission through the axial injection line andthe cyclotron. The ion beam emittance has been measured for various ionmasses and charge states. Beam transport simulations including spacecharge effects were performed for both of the injection line and the ionsource extraction. The relatively low nominal injection voltage of 10 kVwas found to be the main factor for ion beam losses, because of beam blowup due to space charge forces at higher intensities. Consequently,experiments and simulations have been performed at higherinjectionenergies, and it was demonstrated that the ion beams could still becentered in the cyclotron at these energies. Therefore, the new injectorion source VENUS and its ion beam transport system (currently underconstruction at the 88-Inch Cyclotron) are designed for extractionvoltages up to 30 kV.

The idea of producing beams of high energy photons by Compton backscattering of laser photons was proposed over 20 years ago. At the time, producing the required laser pulses was not feasible. However, recent advances in high average power, diode pumped lasers appear to have solved this problem. The US Collaboration is now turning its attention to the engineering requirement of mating the laser and optics components with the accelerator structures in the confined space of the a colliding beam interaction region. The demonstration of a technically feasible interaction region design is planned for the Snowmass conference in 2001.

We report on the commissioning of a higher harmonic RF system designed to improve the Touschek lifetime of the Advanced Light Source. In our best results, we have achieved over a factor of two increase in the beam lifetime. Transient beam loading of the harmonic cavities by unequal fill patterns presents the greatest limitations on lifetime improvement. We also describe several interesting effects of the harmonic cavities on the operation of the longitudinal and transverse multibunch feedback systems.

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{beta}-Carotene is a tetraterpenoid distributed widely throughout the plant kingdom. It is a member of a group of pigments referred to as carotenoids that have the distinction of serving as metabolic precursors to vitamin A in humans and many animals [1,2]. We used Accelerator Mass Spectrometry (AMS) [3] to determine the metabolic behavior of a physiologic oral dose of {beta}-[{sup 14}C]carotene (200 nanoCuries; 0.57 {micro}mol) in a healthy human subject. Serial blood specimens were collected for 210-d and complete urine and feces were collected for 17 and 10-d, respectively. Balance data indicated that the dose was 42% bioavailable. The absorbed {beta}-carotene was lost slowly via urine in accord with the slow body turnover of {beta}-carotene and vitamin A [4]. HPLC fractionation of plasma taken at early time points (0-24-h) showed the label was distributed between {beta}-carotene and retinyl esters (vitamin A) derived from intestinal metabolism.

The CH2M HILL Hanford Group (CHG) conducts business to achieve the goals of the U.S. Department of Energy's (DOE) Office of River Protection at the Hanford Site. The CHG is organized to manage and perform work to safely store, retrieve, etc.

One of the most important scenarios for atmospheric modelers is the stable boundary layer (SBL). Airborne material released near the ground will likely be trapped near the ground in high concentrations due to the reduced dispersion in the SBL. Hence the SBL is often the worst case scenario for studies of health impacts from routine or accidental release of toxic materials to the atmosphere. Unfortunately the SBL is very challenging to understand and model correctly. There is also a limited number of field studies with which to verify models, although recent studies (such as CASES-99) are promising. It is difficult for traditional Reynolds-averaged models of turbulence to capture the weak, spatially- and temporally-varying fluctuations that contribute to dispersion the SBL. Large-eddy simulation (LES) has become a promising approach study the SBL because much of the dynamical structure is explicitly resolved and allowed to develop according to the full equations of motion. The presence of topography further complicates the simulation of SBL flows. The drainage flows that develop as the surface cools must be resolved, along with their interaction with other drainage flows of varying scales and the main forcing (synoptic scale) flow. In this study, we have used LES techniques …

The major consumer electronics in U.S. homes accounted for over 10 percent of U.S. residential electricity consumption, which is comparable to the electricity consumed by refrigerators or lighting. We attribute 3.6 percent to video products, 3.3 percent to home office equipment, and 1.8 percent to audio products. Televisions use more energy than any other single product category, but computer energy use now ranks second and is likely to continue growing. In all, consumer electronics consumed 110 THw in the U.S. in 1999, over 60 percent of which was consumed while the products were not in use.

The United States Department of Energy (DOE) is investigating Yucca Mountain, Nevada, for its feasibility as a potential deep geological repository of high-level nuclear waste. In a deep geological repository, radioactive decay heat released from high-level nuclear waste will heat up the rock mass. Although the following discussion about the thermal-hydrological (TH) process may not be directly relate to the topic of this paper, it provides a bigger picture of the processes in a potential repository. The heat will mobilize pore water in the rock mass by evaporation, or boiling if the thermal load is great enough. The water vapor/steam will flow away from the heat source because of pressure and thermal gradients and the effects of buoyancy force. The vapor/steam will flow along fractures or highly permeable zones and condense into liquid water in the cooler regions. Gravity and the fracture network will control the drainage of the condensed water. Some water may flow back toward the waste package and re-evaporate. This TH process will affect the amount of water that may come into contact with the waste package. Water is the main concern in maintaining the integrity of the waste package and the waste form, and the potential …

The United States Department of Energy (DOE) is investigating Yucca Mountain, Nevada, for its feasibility as a potential deep geological repository of high-level nuclear waste. In a deep geological repository, the radioactive decay heat released from high-level nuclear waste will heat up the rock mass. The heat will mobilize pore water in the rock mass by evaporation, and even boiling, if the thermal load is great enough. The water vapor/steam will flow away from the heat source because of pressure and thermal gradients and the effects of buoyancy force. The vapor/steam may flow along fractures or highly permeable zones and condense into liquid water in the cooler regions. Gravity and fracture network will control the drainage of the condensed water. Some of the water may flow back toward the waste package and reevaporated. This thermal-hydrological (TH) process will affect the amount of water that may come into contact with the waste package. Water is the main concern for the integrity of the waste package and the waste form, and the potential transport of radioactive nuclides. Thermally driven chemical and mechanical processes may affect the TH process. The coupled thermal-hydrological-mechanical-chemical (THMC) processes need to be understood before the performance of a …

We present a Plasma Wakefield Acceleration (PWFA) scheme that can in principle provide an acceleration gradient above 100 GeV/m, based on a reasonable modification of the existing SLAC beam parameters. We also study a possible up-grade of the Stanford Linear Collider (SLC) to hundreds of GeV center-of-mass energy using such a PWFA as a booster. The emittance degradation of the accelerated beams by the plasma wakefield focus is relatively small due to a uniform transverse distribution of the driving beam and the single stage acceleration.

In an effort to develop a more extensive model for the thermomechanical behavior of shape memory alloy (SMA) films, a novel characterization method has been developed. This automated test has been tailored to characterize films for use in micro-electromechanical system (MEMS) actuators. The shape memory effect in NiTiCu is seen in the solid-state phase transformation from an easily deformable low-temperature state to a 'shape remembering' high-temperature state. The accurate determination of engineering properties for these films necessitates measurements of both stress and strain in microfabricated test structures over the full range of desired deformation. Our various experimental methods (uniaxial tensile tests, bimorph curvature tests and diaphragm bulge tests) provide recoverable stress and strain data and the stress-strain relations for these films. Tests were performed over a range of temperatures by resistive heating or ambient heating. These measurements provide the results necessary for developing active SMA structural film design models.

The Electron Cyclotron Emission (ECE) diagnostic on FTU tokamak is routinely performed with a Michelson interferometer with spectral range extending up to 1300 GHz. The diagnostic allowed accurate electron temperature measurements during the recent 140 Ghz Electron Cyclotron Resonance Heating (ECRH) experiments on FTU. Very accurate measurements have been performed on a wide range of electron temperatures and profile peaking. The ECE measurements have been compared with Thomson Scattering and with observations of X-ray spectra from highly stripped molybdenum ions. The suprathermal emission in these conditions has been studied.

Aluminum-based spent nuclear fuel (Al-SNF) from foreign and domestic research reactors is being consolidated at the Savannah River Site (SRS) for ultimate disposal in the Mined Geologic Disposal System (MGDS). Most of the aluminum-based fuel material contains highly enriched uranium (HEU) (greater than 20 percent {sup 235}U), which poses a proliferation risk and challenges the preclusion of criticality events for disposal periods exceeding 10,000 years.

Residual environmental sound can mask intrusive4 (unwanted) sound. It is a factor that can affect noise impacts and must be considered both in noise-impact studies and in noise-mitigation designs. Models for quantitative prediction of sensation level (audibility) and psychological effects of intrusive noise require an input with 1/3 octave-band spectral resolution of environmental masking noise. However, the majority of published residual environmental masking-noise data are given with either octave-band frequency resolution or only single A-weighted decibel values. A model has been developed that enables estimation of 1/3 octave-band residual environmental masking-noise spectra and relates certain environmental parameters to A-weighted sound level. This model provides a correlation among three environmental conditions: measured residual A-weighted sound-pressure level, proximity to a major roadway, and population density. Cited field-study data were used to compute the most probable 1/3 octave-band sound-pressure spectrum corresponding to any selected one of these three inputs. In turn, such spectra can be used as an input to models for prediction of noise impacts. This paper discusses specific algorithms included in the newly developed computer program ENMASK. In addition, the relative audibility of the environmental masking-noise spectra at different A-weighted sound levels is discussed, which is determined by using the methodology …

Acid deposition is a serious problem throughout much of Asia. Emissions of sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) have been increasing steadily, as nations strive to increase their levels of economic development. Coal and fuel oil have been the main choices for powering industrial development; and, until recently, only a few countries (notably Japan and Taiwan) had taken significant steps to avert the atmospheric emissions that accompany fuel combustion. This paper discusses trends in emissions of SO{sub 2} and NO{sub x} that have occurred in Asian countries in the period 1985--1997, using results from the RAINS-ASIA computer model and energy-use trends from the IEA Energy Statistics and Balances database. Emissions of SO{sub 2} in Asia grew from 26.6 Tg in 1985 to 33.7 Tg in 1990 and to 39.2 Tg in 1997. Though SO{sub 2} emissions used to grow as fast as fossil-fuel use, recent limitations on the sulfur content of coal and oil have slowed the growth. The annual-average emissions growth between 1990 and 1997 was only 1.1%, considerably less than the economic growth rate. Emissions of NO{sub x}, on the other hand, continue to grow rapidly, from 14.1 Tg in 1985 to 18.7 Tg in …

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The option of storage and eventual geologic disposal in Russia of spent fuel of US origin used in Taiwan provides a unique opportunity that can benefit many parties. Taiwan has a near term need for a spent fuel storage and geologic disposal solution, available financial resources, but limited prospect for a timely domestic solution. Russia has significant spent fuel storage and transportation management experience, candidate storage and repository sites, but limited financial resources available for their development. The US has interest in Taiwan energy security, national security and nonproliferation interests in Russian spent fuel storage and disposal and interest in the US origin fuel. While it is understood that such a project includes complex policy and international political issues as well as technical issues, the goal of this paper is to begin the discussion by presenting a technical path forward to establish the feasibility of this concept for Russia.

In this paper the authors consider applications of methods from wavelet analysis to nonlinear dynamical problems related to accelerator physics. In this approach they take into account underlying algebraical, geometrical and topological structures of corresponding problems.

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The density of threading dislocations (TD) in GaN grown directly on flat sapphire substrates is typically greater than 10{sup 9}/cm{sup 2}. Such high dislocation densities degrade both the electronic and photonic properties of the material. The density of dislocations can be decreased by orders of magnitude using cantilever epitaxy (CE), which employs prepatterned sapphire substrates to provide reduced-dimension mesa regions for nucleation and etched trenches between them for suspended lateral growth of GaN or AlGaN. The substrate is prepatterned with narrow lines and etched to a depth that permits coalescence of laterally growing III-N nucleated on the mesa surfaces before vertical growth fills the etched trench. Low dislocation densities typical of epitaxial lateral overgrowth (ELO) are obtained in the cantilever regions and the TD density is also reduced up to 1 micrometer from the edge of the support regions.

The 1994 Accident Sequence Precursor (ASP) human reliability analysis (HRA) methodology was developed for the U.S. Nuclear Regulatory Commission (USNRC) in 1994 by the Idaho National Engineering and Environmental Laboratory (INEEL). It was decided to revise that methodology for use by the Simplified Plant Analysis Risk (SPAR) program. The 1994 ASP HRA methodology was compared, by a team of analysts, on a point-by-point basis to a variety of other HRA methods and sources. This paper briefly discusses how the comparisons were made and how the 1994 ASP HRA methodology was revised to incorporate desirable aspects of other methods. The revised methodology was renamed the SPAR HRA methodology.

Experimental methods are discussed for studying band structure, effective mass, and other electronic properties relevant to mobility, including scattering mechanisms, relaxation time, and the influence of grain boundaries (GBs) in polycrystalline transparent conducting oxide (TCO) films. Impedance spectroscopy permits evaluation of the GB potential barrier height and density-of-states. These studies enable an estimate of the limiting mobility achievable for practical transparent conducting oxides to be made. The equipment for measurement of the four transport coefficients is discussed, and examples of its application to films of ZnO, SnO2, and Cd2SnO4 are given.

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