Scientists in the Physical Biosciences Division of the Ernest Orlando Berkeley National Laboratory (Berkeley Lab) studying transition metals in proteins with fluorescence-detected L-edge absorption spectroscopy have found the measurements to be extremely challenging. The difficulty is that the metal centers are present in very dilute concentrations so that their weak fluorescence is often obscured by strong background signals carbon and oxygen. To solve this problem, the Berkeley group has been working with researchers from the Advanced Detector Group at the Lawrence Livermore National Laboratory on an energy-dispersive superconducting tunnel junction x-ray detector. These devices in principle have the energy resolution needed to reveal the metal signal. The most recent results with the latest version of the detector on Beamline 4.0.1-2 at the Advanced Light Source (ALS) illustrate the promise of the cryogenic detector strategy not only for this application but also for spectroscopy of other types of dilute samples. Transition-metal complexes are key elements in many biologically important processes that are catalyzed by proteins (enzymes), photosynthesis being a prime example. The changes in that occur in electronic structure throughout a catalytic cycle are the subject of much research aimed at understanding the mechanisms of these processes. L-edge x-ray spectroscopy offers …

The changes in the patterns of energy use and expenditures by population group are analyzed by using the 1993 and 1997 Residential Energy Consumption Surveys. Historically, these patterns have differed among non-Hispanic White households, non-Hispanic Black households, and Hispanic households. Patterns of energy use and expenditures are influenced by geographic and metropolitan location, the composition of housing stock, economic and demographic status, and the composition of energy use by end-use category. As a consequence, as energy-related factors change across groups, patterns of energy use and expenditures also change. Over time, with changes in the composition of these factors by population group and their variable influences on energy use, the impact on energy use and expenditures has varied across these population groups.

A test methodology for measuring temperature, impedance, pH, and electrochemical potential distributions within a sludge-packed tube support plate crevice in a laboratory test is described. The method successfully showed that there were large concentration gradients between the tube and tube support plate sides of the crevice. The testing also showed that strong bases concentrated more effectively than strong acids, and that the crevice pH, when exposed to seawater-based solutions, increased with increasing superheat and decreasing bulk concentration. The large variations in the crevice chemistry observed under heat transfer were eliminated upon shutdown. These new test data suggest that it might be beneficial to evaluate the variation in the extent of stress corrosion cracking with tube support plate elevation found in some steam generators in light of local chemistry changes, as well as the variation in tubing temperature. Because of the large crevice chemistry gradients during boiling heat transfer and their subsequent homogenization upon test shutdown, the results suggest reassessing the use of hideout return measurements and tube deposit analyses in industry to infer the crevice chemistry under heat transfer conditions.

The U.S. Department of Energy (DOE) is considering the possible recommendation of a site at Yucca Mountain, Nevada, for development as a geologic repository for the disposal of high-level radioactive waste and spent nuclear fuel. To facilitate public review and comment, in May 2001 the DOE released the Yucca Mountain Science and Engineering Report (S&ER) (DOE 2001 [DIRS 153849]), which presents technical information supporting the consideration of the possible site recommendation. The report summarizes the results of more than 20 years of scientific and engineering studies. A decision to recommend the site has not been made: the DOE has provided the S&ER and its supporting documents as an aid to the public in formulating comments on the possible recommendation. When the S&ER (DOE 2001 [DIRS 153849]) was released, the DOE acknowledged that technical and scientific analyses of the site were ongoing. Therefore, the DOE noted in the Federal Register Notice accompanying the report (66 FR 23013 [DIRS 155009], p. 2) that additional technical information would be released before the dates, locations, and times for public hearings on the possible recommendation were announced. This information includes: (1) the results of additional technical studies of a potential repository at Yucca Mountain, contained …

This report describes a hazard and accident analysis conducted for Site 300 operations to support update of the ''Site 300 B-Division Firing Areas Safety Analysis Report'' (SAR) [LLNL 1997]. A significant change since the previous SAR is the construction and the new Contained Firing Facility (CFF). Therefore, this hazard and accident analysis focused on the hazards associated with bunker operations to ensure that the hazards at CFF are properly characterized in the updated SAR. Hazard tables were created to cover both the CFF and the existing bunkers with ''open air'' firing tables.

Gov. Davis issued Executive Order D-5-99 in March 1999 calling for removal of methyl tertiary butyl ether (MTBE) from gasoline no later than December 31, 2002. The Executive Order required the California Air Board, State Water Resources Control Board (SWRCB) and Office of Environmental Health Hazard Assessment (OEHHA) to prepare an analysis of potential impacts and health risks that may be associated with the use of ethanol as a fuel oxygenate. The SWRCB contracted with the Lawrence Livermore National Laboratory (LLNL) to lead a team of researchers, including scientists from Clarkson University, University of Iowa, and University of California, Davis, in evaluating the potential ground and surface water impacts that may occur if ethanol is used to replace MTBE. These findings are reported in the document entitled Health and Environmental Assessment of the Use of Ethanol as a Fuel Oxygenate. This document has been peer reviewed and presented to the California Environmental Policy Council and may be viewed at: http://www-erd.llnl.gov/ethanol/. Ethanol used for fuels is made primarily from grains, but any feed stock containing sugar, starch, or cellulose can be fermented to ethanol. Ethanol contains 34.7% oxygen by weight. It is less dense than water, but infinitely soluble in water. …

The Steven Test was developed to determine relative impact sensitivity of metal encased solid high explosives and also be amenable to two-dimensional modeling. Low level reaction thresholds occur at impact velocities below those required for shock initiation. To assist in understanding this test, multi-dimensional gauge techniques utilizing carbon foil and carbon resistor gauges were used to measure pressure and event times. Carbon resistor gauges indicated late time low level reactions 200-540 {micro}s after projectile impact, creating 0.39-2.00 kb peak shocks centered in PBX 9501 explosives discs and a 0.60 kb peak shock in a LX-04 disk. Steven Test modeling results, based on ignition and growth criteria, are presented for two PBX 9501 scenarios: one with projectile impact velocity just under threshold (51 m/s) and one with projectile impact velocity just over threshold (55 m/s). Modeling results are presented and compared to experimental data.

U.S. MPC&A cooperation with the Russian Federation (RF) Navy is based on a Joint Statement signed in 1996 to protect Highly Enriched Uranium (HEU) fresh fuel used for nuclear propulsion. The Russian Federation Navy is the largest owner in Russia of highly enriched uranium, both in the form of fresh nuclear fuel, and in the form of slightly irradiated fuel with a long cooling time after irradiation. As a result of this agreement, projects began at the Northern Fleet Fresh Fuel Storage Facility (Site 49) and Refueling Ship PM-63. Initial projects provided upgrades for RF Navy HEU fresh fuel storage facilities, beginning with a land-based facility near Murmansk and later adding other land-based and ship-based fresh fuel storage facilities. Additional protocols (December 1997, January 1999, and March 2000) significantly expanded cooperation to include all HEU fuel under RF Navy control. To date, it is estimated that tens of metric tons of HEU have been secured - enough to construct hundreds of nuclear devices. It was determined that the cooperation would be coordinated by the Russian Research Center, Kurchatov Institute. This paper describes the history of the Program development, its stages, current status, scale of the work and prospects.

The Accelerated Strategic Computing Initiative (ASCI) Problem Solving Environment (PSE) consists of the tools and libraries needed for the development of ASCI simulation codes on ASCI machines. The recently completed ASCI PSE Milepost demonstrated that this software environment is available and functional at the scale used for application mileposts on ASCI White. As part of the PSE Milepost, we performed extensive performance testing of several critical run-time based systems. In this paper, we present microbenchmark results that compare the MPI [5], Pthreads and OpenMP [7, 8] implementations on ASCI White and ASCI Blue Pacific. Our results demonstrate that these run-time systems on White have improved sufficiently to accommodate the machine's approximately four-fold increase in processing capability over Blue Pacific.

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Wet-etch figuring (WEF), a computer-controlled method for generating arbitrarily shaped optical surfaces using wet chemical etching, has been developed. This method uses applicator geometry and surface tension gradients (the Marangoni Effect) to define and confine the footprint of a wetted etchant zone on the surface. Capillary forces attach the flowing etchant solution to the underside of the optic being figured. No mechanical or thermal stresses or residues are applied to the optic by this process. This enables interferometric measurement of the glass thickness while surfacing, which then controls the placement and dwell time of the wetted zone. The result is a truly deterministic, closed-loop figuring process with a high degree of optical precision. This process can figure sub-millimeter thickness, large-aperture plates or sheets that are very difficult to finish by conventional methods. Automated linear and circular spot etching tools were used to demonstrate surfacing on 380 micron-thick glass sheets, to Strehl better than 0.8, as specified by data array or Zernike polynomials.

Single solid-state devices or arrays of solid-state devices are being incorporated into many pulsed power applications as a means of generating fast, high-power, high repetition-rate pulses and ultimately replacing hard tubes and thyratrons. While vendors' data sheets provide a starting point for selecting solid-state devices, most data sheets do not have sufficient information to determine performance in a pulsed application. To obtain this relevant information, MOSFET's and IGBT's from a number of vendors have been tested to determine rise times, fall times and current handling capabilities. The emphasis is on the evaluation of devices that can perform in the range of 100ns pulse widths and the test devices must be capable of switching 1000 volts or greater at a pulsed current of at least 25 amperes. Additionally, some devices were retest with a series magnetic switch to evaluate the effects on switching parameters and specifically rise times. All devices were evaluated under identical conditions and the complete test results are presented.

This paper presents a plan for increasing the mapped resource base for geothermal exploration in the Western US. We plan to image large areas in the western US with recently developed high resolution hyperspectral geobotanical remote sensing tools. The proposed imaging systems have the ability to map visible faults, surface effluents, historical signatures, and discover subtle hidden faults and hidden thermal systems. Large regions can be imaged at reasonable costs. The technique of geobotanical remote sensing for geothermal signatures is based on recent successes in mapping faults and effluents the Long Valley Caldera and Mammoth Mountain in California.

In an effort to increase automobile fuel efficiency as well as decrease the output of harmful greenhouse gases, the automotive industry has recently shown increased interest in cast light metals such as magnesium alloys in an effort to increase weight savings. Currently several magnesium alloys such as AZ91 and AM60B are being used in structural applications for automobiles. However, these magnesium alloys are not as well characterized as other commonly used structural metals such as aluminum. This dissertation presents a methodology to nondestructively quantify damage accumulation due to void behavior in three dimensions in die-cast magnesium AM60B tensile bars as a function of mechanical load. Computed tomography data was acquired after tensile bars were loaded up to and including failure, and analyzed to characterize void behavior as it relates to damage accumulation. Signal and image processing techniques were used along with a cluster labeling routine to nondestructively quantify damage parameters in three dimensions. Void analyses were performed including void volume distribution characterization, nearest neighbor distance calculations, shape parameters, and volumetric renderings of voids in the alloy. The processed CT data was used to generate input files for use in finite element simulations, both two- and three-dimensional. The void analyses revealed …

Al 5083 disks of a superplastic forming grade were gas-pressure formed to hemispheres and cones at constant forming pressures with and without back pressure. The forming operation was performed using an in-house designed and built biaxial forming apparatus. The temporal change of dome heights of the hemispheres and cones were measured for the different forming and back pressures applied. The flow stresses and strain rates developed at the top of the dome during the forming step were shown to closely follow the flow stress-strain rate relationship obtained from the strain rate change tests performed at the same temperature using uniaxial tensile samples.

(1) LLNL measured the material removal rate from stainless steel, silicon carbide, rhenium, N5, hastalloy X, and titanium as a function of pulse fluence at a wavelength of 810 nm for pulse durations of 150 fs, 1.5 ps, 20 ps, and 500 ps. The spot size of the beam used was 150 microns in diameter and the nominal material thickness was 1-2 mm. These experiments were performed on the existing 1 kHz laser system. Holes of different penetration depths were obtained to ascertain change in removal rate as a function of depth. Measurements included electron microscopy of selected samples. (2) The experiments in I were repeated for all materials but select pulse durations with the sample in a vacuum of base pressure 10 mTorr to determine if hole quality and ablation rate is improved. (3) LLNL measured material removal rate from stainless steel, silicon carbide, rhenium, N5, hastalloy X, and titanium as a function of pulse fluence at a wavelength of 532 nm for pulse duration at 200 ns. The spot size of the beam used was 200 microns in diameter and the material thickness was the same as in task I. Holes of different penetration depths were obtained to …

Solid-state lasers have held great promise for the generation of high-average-power, high-quality output beams for a number of decades. However, the inherent difficulty of scaling the active solid-state gain media while continuing to provide efficient cooling has limited demonstrated powers to <5kW. Even at the maximum demonstrated average powers, the output is most often delivered as continuous wave (CW) or as small energy pulses at high pulse repetition frequency (PRF) and the beam divergence is typically >10X the diffraction limit. Challenges posed by optical distortions and depolarization arising from internal temperature gradients in the gain medium of a continuously cooled system are only increased for laser designs that would attempt to deliver the high average power in the form of high energy pulses (>25J) from a single coherent optical aperture. Although demonstrated phase-locking of multiple laser apertures may hold significant promise for the future scaling of solid-state laser systems,1 the continuing need for additional technical development and innovation coupled with the anticipated complexity of these systems effectively limits this approach for near-term multi-kW laser operation outside of a laboratory setting. We have developed and demonstrated a new operational mode for solid-state laser systems in which the cooling of the gain …

We describe the design and MPI implementation of two benchmarks created to characterize the balanced system performance of high-performance clusters and supercomputers: b{_}eff, the communication-specific benchmark examines the parallel message passing performance of a system, and b{_}eff{_}io, which characterizes the effective 1/0 bandwidth. Both benchmarks have two goals: (a) to get a detailed insight into the Performance strengths and weaknesses of different parallel communication and I/O patterns, and based on this, (b) to obtain a single bandwidth number that characterizes the average performance of the system namely communication and 1/0 bandwidth. Both benchmarks use a time driven approach and loop over a variety of communication and access patterns to characterize a system in an automated fashion. Results of the two benchmarks are given for several systems including IBM SPs, Cray T3E, NEC SX-5, and Hitachi SR 8000. After a redesign of b{_}eff{_}io, I/O bandwidth results for several compute partition sizes are achieved in an appropriate time for rapid benchmarking.

The purpose of this White Paper is to outline the benefits we expect to receive from Model-Based Engineering and Manufacturing (MBE/M) for the design, analysis, fabrication, and assembly of nuclear weapons for upcoming Life Extension Programs (LEPs). Industry experiences with model-based approaches and the NNSA/DP investments and experiences, discussed in this paper, indicate that model-based methods can achieve reliable refurbished weapons for the stockpile with less cost and time. In this the paper, we list both general and specific benefits of MBE/M for the upcoming LEPs and the metrics for determining the success of model-based approaches. We also present some outstanding issues and challenges to deploying and achieving long-term benefit from the MBE/M. In conclusion, we argue that successful completion of the upcoming LEPs--with very aggressive schedule and funding restrictions--will depend on electronic model-based methods. We ask for a strong commitment from LEP managers throughout the Nuclear Weapons Complex to support deployment and use of MBE/M systems to meet their program needs.

Adaptive optics (AO) on 8-10 m telescopes is an enormously powerful tool for studying young nearby stars. It is especially useful for searching for companions. Using AO on the 10-m W.M. Keck II telescope we have measured the position of the brown dwarf companion to TWA5 and resolved the primary into an 0.055{double_prime} double. Over the next several years follow-up astrometry should permit an accurate determination of the masses of these young stars. We have also re-observed the candidate extrasolar planet TWAGB, but measurements of its motion relative to TWA6A are inconclusive. We are carrying out a search for new planetary or brown dwarf companions to TWA stars and, if current giant planet models are correct, are currently capable of detecting a 1 Jupiter-mass companion at {approx} 1.0{double_prime} and a 5 Jupiter-mass companion at {approx} 0.5{double_prime} around a typical TWA member.

This document reports the results of the 25 Can Verification Run. The 25 Can Verification Run was performed as outlined in Section 1.d of SRS Acceptance Criteria (Reference 1). The run was performed over the period of February 16 to the 28, 2001. Each of these cans was welded with a dummy Inner Can containing about 5 kg of surrogate material. The cans were then analyzed using radiography and metallography of samples taken at four locations of the weld. The radiographs were examined for porosity. The micrographs of the metallurgical samples were examined for porosity, cracks, and lack of fusion. The results were reviewed by Derrill Rikard (a level 3 inspector at LLNL) and by Ken Durland (a level 3 inspector from WSRC). These reviews did not find anything of concern. Therefore we are submitting these results to SRS for concurrence.

Statistical analysis gives a paradigm for detection and tracking of weak-signature sources that are moving among a network of detectors. The detector platforms compute and exchange information with near-neighbors in the form of Bayesian probabilities for possible sources. This can shown to be an optimal scheme for the use of detector information and communication resources. Here, we apply that paradigm to the detection and discrimination of radiation sources using multi-channel gamma-ray spectra. We present algorithms for the reduction of detector data to probability estimates and the fusion of estimates among multiple detectors. A primary result is the development of a goodness-of-fit metric, similar to {chi}{sup 2}, for template matching that is statistically valid for spectral channels with low expected counts. Discrimination of a target source from other false sources and detection of imprecisely known spectra are the main applications considered. We use simulated NaI spectral data to demonstrate the Bayesian algorithm compare it to other techniques. Results of simulations of a network of spectrometers are presented, showing its capability to distinguish intended targets from nuisance sources.

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The second out of a series of three fact sheets describing the role of electricity markets and market design in integrating solar generation.