The Mirror Fusion Test Facility is a major magnetic fusion energy project at the Lawrence Livermore National Laboratory. An important component of this facility is the vacuum vessel, which forms the vacuum chamber. The vessel is supported on twenty-two pairs of legs that rest on reinforced concrete piers. In performing static and dynamic analyses on the vacuum vessel, we separately investigated the load distribution under gravity loads, pressure loads, electromagnetic loads, and thermal loads. We also performed sophisticated dynamic analyses to predict the structural behavior under a postulated earthquake. The modeling assumptions and analytic procedures are highlighted in this paper.

Most analytical and experimental approaches to the evaluation of fluid-structure interaction (FSI) effects in the General Electric Mark I BWR pressure suppression system treat the torus shell as rigid when the shell in real systems is flexible. This report describes linear three-dimensional finite-element analyses of one torus bay that investigated the qualitative effect of torus wall flexibility on hydrodynamic loads induced by a nominal safety relief valve (SRV) discharge. The results of these analyses support the general conclusion drawn from earlier two-dimensional analyses. The report also discusses finite-element analyses of a 3-D representation of the earlier 2-D plane-strain model of the torus shell.

This report describes a series of extended analyses requested by the US Nuclear Regulatory Commission to provide qualified understanding of possible fluid/structure interaction (FSI) effects for SRV teequencher test results. Three input pulses with total impulses varying by up to a factor of five are applied to two-dimensional finite-element models of the Mark I torus with shell diameter-to-thickness ratios of 0, 300, and 600. The results of these analyses support earlier conclusions that increased wall flexibility enhances attenuation of hydrodynamic loads and furthermore indicate that the magnitude of the attenuation is only weakly affected by the total impulse of the bubble pressure time-history.

Starch branching enzyme (SBE) activity in the cassava storage root exhibited a diurnal fluctuation, dictated by a transcriptional oscillation of the corresponding SBE genes. The peak of SBE activity coincided with the onset of sucrose accumulation in the storage, and we conclude that the oscillatory mechanism keeps the starch synthetic apparatus in the storage root sink in tune with the flux of sucrose from the photosynthetic source. When storage roots were uncoupled from the source, SBE expression could be effectively induced by exogenous sucrose. Turanose, a sucrose isomer that cannot be metabolized by plants, mimicked the effect of sucrose, demonstrating that downstream metabolism of sucrose was not necessary for signal transmission. Also glucose and glucose-1-P induced SBE expression. Interestingly, induction by sucrose, turanose and glucose but not glucose-1-P sustained an overt semidian (12-h) oscillation in SBE expression and was sensitive to the hexokinase (HXK) inhibitor glucosamine. These results suggest a pivotal regulatory role for HXK during starch synthesis. Abscisic acid (ABA) was another potent inducer of SBE expression. Induction by ABA was similar to that of glucose-1-P in that it bypassed the semidian oscillator. Both the sugar and ABA signaling cascades were disrupted by okadaic acid, a protein phosphatase inhibitor. …

To meet the needs of a growing population and to provide us with a higher quality of life, increasing pressures are being placed on our environment through the development of agriculture, industry, and infrastructures. Soil erosion, groundwater depletion, salinization, and pollution have been recognized for decades as major threats to ecosystems and human health. More recently, the progressive substitution of fossil fuels by biofuels for energy production and climate change have been recognized as potential threats to our water resources and sustained agricultural productivity. The vadose zone mediates many of the processes that govern water resources and quality, such as the partition of precipitation into infiltration and runoff , groundwater recharge, contaminant transport, plant growth, evaporation, and energy exchanges between the Earth's surface and its atmosphere. It also determines soil organic carbon sequestration and carbon-cycle feedbacks, which could substantially impact climate change. The vadose zone's inherent spatial variability and inaccessibility precludes direct observation of the important subsurface processes. In a societal context where the development of sustainable and optimal environmental management strategies has become a priority, there is a strong prerequisite for the development of noninvasive characterization and monitoring techniques of the vadose zone. In particular, hydrogeophysical approaches applied at …

Here we show that labile particulate iron and manganese concentrations in the upper 500m of the Western Subarctic Pacific, an iron-limited High Nutrient Low Chlorophyll (HNLC) region, have prominent subsurface maxima between 100-200 m, reaching 3 nM and 600 pM, respectively. The subsurface concentration maxima in particulate Fe are characterized by a more reduced oxidation state, suggesting a source from primary volcagenic minerals such as from the Kuril/Kamchatka margin. The systematics of these profiles suggest a consistently strong lateral advection of labile Mn and Fe from redox-mobilized labile sources at the continental shelf supplemented by a more variable source of Fe from the upper continental slope. This subsurface supply of iron from the continental margin is shallow enough to be accessible to the surface through winter upwelling and vertical mixing, and is likely a key source of bioavailable Fe to the HNLC North Pacific.

Using 226 million B{bar B} events recorded on the {Upsilon}(4S) resonance with the BABAR detector at the SLAC e{sup +}e{sup -} PEP-II storage rings, they reconstruct B{sup -} {yields} D*{sup 0}e{sup -}{bar {nu}}{sub e} decays using the decay chain D*{sup 0} {yields} D{sup 0}{pi}{sup 0} and D{sup 0} {yields} K{sup -} {pi}{sup +}. From the dependence of their differential rate on the w, the dot product of the four-velocities of B{sup -} and D*{sup 0}, and using the form factor description by Caprini et al. with the parameters F(1) and {rho}{sub 1{sub 1}}{sup 2}, they obtain the results {rho}{sub A{sub 1}}{sup 2} = 1.16 {+-} 0.06 {+-} 0.08, F(1) {center_dot} |V{sub cb}| = (35.9 {+-} 0.6 {+-} 1.4) {center_dot} 10{sup -3}, and {beta}(B{sup -} {yields} D*{sup 0} e{sup -}{bar {nu}}{sub e}) = (5.56 {+-} 0.08 {+-} 0.41)%.

Recognizing the role that semiconductor suppliers can playin meeting energy-efficiency regulations and voluntary specifications,this paper provides an overview of Chinese policies and implementingbodies; a discussion of current programs, their goals, and effectiveness;and possible steps that can be taken tomeet these energy-efficiencyrequirements while also meeting products' high performance and costgoals.

This study addresses the issue of waste and cover subsidence caused by corrosion of the non-crushable waste containers defined as containers with significant void space that will not be stabilized by dynamic compaction of the Earea Slit Trenches at the Savannah River Site. Concentrations at the hypothetical 100-m well were evaluated for 1,000 years and compared with the base case value for compliance. To generalize the results, a hypothetical, no-decay radionuclide characterized by a Kd (5 ml/g) that would be most problematic was selected. Although the non-crushable containers will not be stabilized by dynamic compaction, these containers will gradually corrode, eventually collapse after placement of the final closure cap and cause the cap to subside resulting in an increase of the infiltration rates. The vadose zone model estimated the contaminant fluxes that were input to the aquifer model for prediction of concentrations at the 100-m well. To study the potential effect of trench subsidence on the well concentrations within the 1000-year time window, two high-impact cases were considered. In the first case, trenches subsided right after dynamic compaction (i.e., at 125 years). In the second case, trenches subsided at 419 years to make the peak concentrations from both the subsided …

This paper describes and demonstrates the use of the coupledTOUGH-FLAC simulator for geomechanical shear-slip (failure) analysis inmultiphase fluid-flow reservoir-engineering applications. Two approachesfor analyzing shear-slip are described, one using continuum stress-strainanalysis and another using discrete fault analysis. The use of shear-slipanalysis in TOUGH-FLAC is demonstrated on application examples related toCO2 sequestration and geothermal energy extraction. In the case of CO2sequestration, the shear-slip analysis is used to evaluate maximumsustainable CO2-injection pressure under increasing reservoir pressure,whereas in the case of geothermal energy extraction, the shear-slipanalysis is used to study induced seismicity during steam productionunder decreasing reservoir pressure and temperature.

The deployment of small (<1-2 MW) clusters of generators,heat and electrical storage, efficiency investments, and combined heatand power (CHP) applications (particularly involving heat activatedcooling) in commercial buildings promises significant benefits but posesmany technical and financial challenges, both in system choice and itsoperation; if successful, such systems may be precursors to widespreadmicrogrid deployment. The presented optimization approach to choosingsuch systems and their operating schedules uses Berkeley Lab'sDistributed Energy Resources Customer Adoption Model [DER-CAM], extendedto incorporate electrical storage options. DER-CAM chooses annual energybill minimizing systems in a fully technology-neutral manner. Anillustrative example for a San Francisco hotel is reported. The chosensystem includes two engines and an absorption chiller, providing anestimated 11 percent cost savings and 10 percent carbon emissionreductions, under idealized circumstances.

Since the initial measurements of the electron charge a century ago, experimenters have faced the persistent question as to whether elementary particles exist that have charges that are fractional multiples of the electron charge. I concisely review the results of the last 50 years of searching for fractional charge particles with no confirmed positive results. I discuss the question of whether more searching is worthwhile?

The U.S. Department of Energy's Office of Environmental Management (DOE-EM) was established to achieve the safe and compliant disposition of legacy wastes and facilities from defense nuclear applications. A large majority of these wastes and facilities are 'one-of-a-kind' and unique to DOE. Many of the programs to treat these wastes have been 'first-of-a-kind' and unprecedented in scope and complexity. This has meant that many of the technologies needed to successfully disposition these wastes were not yet developed or required significant re-engineering to be adapted for DOE-EM's needs. The DOE-EM program believes strongly in reducing the technical risk of its projects and has initiated several efforts to reduce those risks: (1) Technology Readiness Assessments to reduce the risks of deployment of new technologies; (2) External Technical Reviews as one of several steps to ensure the timely resolution of engineering and technology issues; and (3) Technical Risk Ratings as a means to monitor and communicate information about technical risks. This paper will present examples of how Technology Readiness Assessments, External Technical Reviews, and Technical Risk Ratings are being used by DOE-EM to reduce technical risks.

SLAC's COHE program requires compliance with OSHA Regulation 29CFR1910.147, 'The control of hazardous energy (lockout/tagout)'. This regulation specifies lockout/tagout requirements during service and maintenance of equipment in which the unexpected energization or start up of the equipment, or release of stored energy, could cause injury to workers. Class 3B and Class 4 laser radiation must be considered as hazardous energy (as well as electrical energy in associated equipment, and other non-beam energy hazards) in laser facilities, and therefore requires careful COHE consideration. This paper describes how COHE is achieved at SLAC to protect workers against unexpected Class 3B or Class 4 laser radiation, independent of whether the mode of operation is normal, service, or maintenance.

The desire to improve and expand the scope of clinical magnetic resonance imaging (MRI) has prompted the search for contrast agents of higher efficiency. The development of better agents requires consideration of the fundamental coordination chemistry of the gadolinium(III) ion and the parameters that affect its efficacy as a proton relaxation agent. In optimizing each parameter, other practical issues such as solubility and in vivo toxicity must also be addressed, making the attainment of safe, high-relaxivity agents a challenging goal. Here we present recent advances in the field, with an emphasis on the hydroxypyridinone family of Gd{sup III} chelates.

The LCLS at the SLAC National Accelerator Laboratory will be the world's first source of an intense hard x-ray laser beam, generating x-rays with wavelengths of 1nm and pulse durations less than 100fs. The ultrafast x-ray pulses will be used in pump-probe experiments to take stop-motion pictures of atoms and molecules in motion, with pulses powerful enough to take diffraction images of single molecules, enabling scientists to elucidate fundamental processes of chemistry and biology. Ultrafast conventional lasers will be used as the pump. In 2009, LCLS will deliver beam to the Atomic Molecular and Optical (AMO) Experiment, located in one of 3 x-ray Hutches in the Near Experimental Hall (NEH). The NEH includes a centralized Laser Hall, containing up to three Class 4 laser systems, three x-ray Hutches for experiments and vacuum transport tubes for delivering laser beams to the Hutches. The main components of the NEH laser systems are a Ti:sapphire oscillator, a regen amplifier, green pump lasers for the oscillator and regen, a pulse compressor and a harmonics conversion unit. Laser safety considerations and controls for the ultrafast laser beams, multiple laser controlled areas, and user facility issues are discussed.

The bremsstrahlung emitted by an electron scattered in a Coulomb field was first calculated by Bethe and Heitler. The total cross section for production of photons with wave number between k and k + dk by a nonrelativistic electron of kinetic energy {epsilon} is d{sigma}/dk dk = 16/3 Z{sup 2}r{sub 0}{sup 2} (e{sup 2}/hc) (mc{sup 2}/{epsilon})log ({radical} {epsilon}/hck + {radical} {epsilon}/hck -1) dk/k, where Ze is the charge of the (heavy) ion, and r{sub 0} is the classical electron radius. Bremsstrahlung in a plasma has been computed by a number of authors in the approximation of replacing the Coulomb field by a cut-off Coulomb or static Debye potential. It is the purpose of this communication to call attention to another important effect of the medium upon the rate of emission of bremsstrahlung. This may be described as a modification of the relation of the photon's energy to its wave number, due to the index of refraction of the medium. Equivalently, we note that one must include in the calculation of bremsstrahlung in a medium the photon-medium interactions which result in the 'clothing' of a 'bare' photon. The replacement of a particle by a quasiparticle has long been known to be …

Fluor Hanford, Inc. (FH) is proud to submit the Plutonium Finishing Plant (PFP) 241-Z liquid Waste Treatment Facility Deactivation and Demolition (D&amp;D) Project for consideration by the Project Management Institute as Project of the Year for 2008. The decommissioning of the 241-Z Facility presented numerous challenges, many of which were unique with in the Department of Energy (DOE) Complex. The majority of the project budget and schedule was allocated for cleaning out five below-grade tank vaults. These highly contaminated, confined spaces also presented significant industrial safety hazards that presented some of the most hazardous work environments on the Hanford Site. The 241-Z D&amp;D Project encompassed diverse tasks: cleaning out and stabilizing five below-grade tank vaults (also called cells), manually size-reducing and removing over three tons of process piping from the vaults, permanently isolating service utilities, removing a large contaminated chemical supply tank, stabilizing and removing plutonium-contaminated ventilation ducts, demolishing three structures to grade, and installing an environmental barrier on the demolition site . All of this work was performed safely, on schedule, and under budget. During the deactivation phase of the project between November 2005 and February 2007, workers entered the highly contaminated confined-space tank vaults 428 times. Each entry …

Antisense oligodeoxynucleotide (ODN) inhibition emerges as an effective means for probing gene function in plant cells. Employing this method we have established the importance of the SUSIBA2 transcription factor for regulation of starch synthesis in barley endosperm, and arrived at a model for the role of the SUSIBAs in sugar signaling and source-sink commutation during cereal endosperm development. In this addendum we provide additional data demonstrating the suitability of the antisense ODN technology in studies on starch branching enzyme activities in barley leaves. We also comment on the mechanism for ODN uptake in plant cells. Antisense ODNs are short (12-25 nt-long) stretches of single-stranded ODNs that hybridize to the cognate mRNA in a sequence-specific manner, thereby inhibiting gene expression. They are naturally occurring in both prokaryotes and eukaryotes where they partake in gene regulation and defense against viral infection. The mechanisms for antisense ODN inhibition are not fully understood but it is generally considered that the ODN either sterically interferes with translation or promotes transcript degradation by RNase H activation. The earliest indication of the usefulness of antisense ODN technology for the purposes of molecular biology and medical therapy was the demonstration in 1978 that synthetic ODNs complementary to Raos …

We investigate rf SQUIDs (Superconducting QUantum Interference Devices), coupled to a resonant input circuit, a readout tank circuit and a preamplifier, by numerically solving the corresponding Langevin equations and optimizing model parameters with respect to noise temperature. We also give approximate analytic solutions for the noise temperature, which we reduce to parameters of the SQUID and the tank circuit in the absence of the input circuit. The analytic solutions agree with numerical simulations of the full circuit to within 10%, and are similar to expressions used to calculate the noise temperature of dc SQUIDs. The best device performance is obtained when {beta}{sub L}{prime} {triple_bond} 2{pi}LI{sub 0}/{Phi}{sub 0} is 0.6-0.8; L is the SQUID inductance, I{sub 0} the junction critical current and F{sub 0} the flux quantum. For a tuned input circuit we find an optimal noise temperature T{sub N,opt} {approx} 3Tf/f{sub c}, where T, f and f{sub c} denote temperature, signal frequency and junction characteristic frequency, respectively. This value is only a factor of 2 larger than the optimal noise temperatures obtained by approximate analytic theories carried out previously in the limit {beta}{sub L}{prime} &lt;&lt; 1. We study the dependence of the noise temperature on various model parameters, and give …

The ''Drift Shadow'' is defined as the relatively drier region that forms below subsurface cavities or drifts in unsaturated rock. Its existence has been predicted through analytical and numerical models of unsaturated flow. However, these theoretical predictions have not been demonstrated empirically to date. In this project they plan to test the drift shadow concept through field investigations and compare our observations to simulations. Based on modeling studies they have an identified suitable site to perform the study at an inactive mine in a sandstone formation. Pretest modeling studies and preliminary characterization of the site are being used to develop the field scale tests.

When hot radioactive waste is placed in subsurface tunnels, a series of complex changes occurs in the surrounding medium. The water in the pore space of the medium undergoes vaporization and boiling. Subsequently, vapor migrates out of the matrix pore space, moving away from the tunnel through the permeable fracture network. This migration is propelled by buoyancy, by the increased vapor pressure caused by heating and boiling, and through local convection. In cooler regions, the vapor condenses on fracture walls, where it drains through the fracture network. Slow imbibition of water thereafter leads to gradual rewetting of the rock matrix. These thermal and hydrological processes also bring about chemical changes in the medium. Amorphous silica precipitates from boiling and evaporation, and calcite from heating and CO{sub 2} volatilization. The precipitation of amorphous silica, and to a much lesser extent calcite, results in long-term permeability reduction. Evaporative concentration also results in the precipitation of gypsum (or anhydrite), halite, fluorite and other salts. These evaporative minerals eventually redissolve after the boiling period is over, however, their precipitation results in a significant temporary decrease in permeability. Reduction of permeability is also associated with changes in fracture capillary characteristics. In short, the coupled thermal-hydrological-chemical …

When hot radioactive waste is placed in subsurface tunnels, a series of complex changes occurs in the surrounding medium. The water in the pore space of the medium undergoes vaporization and boiling. Subsequently, vapor migrates out of the matrix pore space, moving away from the tunnel through the permeable fracture network. This migration is propelled by buoyancy, by the increased vapor pressure caused by heating and boiling, and through local convection. In cooler regions, the vapor condenses on fracture walls, where it drains through the fracture network. Slow imbibition of water thereafter leads to gradual rewetting of the rock matrix. These thermal and hydrological processes also bring about chemical changes in the medium. Amorphous silica precipitates from boiling and evaporation, and calcite from heating and CO2 volatilization. The precipitation of amorphous silica, and to a much lesser extent calcite, results in long-term permeability reduction. Evaporative concentration also results in the precipitation of gypsum (or anhydrite), halite, fluorite and other salts. These evaporative minerals eventually redissolve after the boiling period is over, however, their precipitation results in a significant temporary decrease in permeability. Reduction of permeability is also associated with changes in fracture capillary characteristics. In short, the coupled thermal-hydrological-chemical (THC) …

High level radioactive liquid waste generated as a result of the production of nuclear material for the United States defense program at the Savannah River Site has been stored as 36 million gallons in underground tanks. About ten percent of the waste volume is sludge, composed of insoluble metal hydroxides primarily hydroxides of Mn, Fe, Al, Hg, and most radionuclides including fission products. The remaining ninety percent of the waste volume is saltcake, composed of primarily sodium (nitrites, nitrates, and aluminates) and hydroxides. Saltcakes account for 30% of the radioactivity while the sludge accounts for 70% of the radioactivity. A pilot plant salt disposition processing system has been designed at the Savannah River Site for interim processing of salt solution and is composed of two facilities: the Actinide Removal Process Facility (ARPF) and the Modular Caustic Side Solvent Extraction Unit (MCU). Data from the pilot plant salt processing system will be used for future processing salt at a much higher rate in a new salt processing facility. Saltcake contains significant amounts of actinides, and other long-lived radioactive nuclides such as strontium and cesium that must be extracted prior to disposal as low level waste. The extracted radioactive nuclides will be …