A study of the laser-plasma interaction processes have been performed in plasmas that are created to emulate the plasma conditions in indirect drive inertial confinement fusion targets. The plasma emulator is produced in a gas-filled hohlraum; a blue 351-nm laser beam propagates along the axis of the hohlraum interacting with a high-temperature (T{sub e} = 3.5 keV), dense (n{sub e} = 5 x 10{sup 20}cm{sup -3}), long-scale length (L {approx} 2 mm) plasma. Experiments at these conditions have demonstrated that the interaction beam produces less than 1% total backscatter resulting in transmission greater than 90% for laser intensities less than I < 2 x 10{sup 15} W-cm{sup -2}. The bulk plasma conditions have been independently characterized using Thomson scattering where the peak electron temperatures are shown to scale with the hohlraum heater beam energy in the range from 2 keV to 3.5 keV. This feature has allowed us to determine the thresholds for both backscattering and filamentation instabilities; the former measured with absolutely calibrated full aperture backscatter and near backscatter diagnostics and the latter with a transmitted beam diagnostics. A plasma length scaling is also investigated extending our measurements to 4-mm long high-temperature plasmas. At intensities I < 5 x …

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Growth rates and the ability to date an organism can greatly contribute to understanding its population biology and community dynamics. 1n 1954, Andreev proposed a method to date Cladina, a fruticose lichen, using total thallus length and number of internodes. No research, however, has demonstrated the reliability of this technique or compared its estimates to those derived by other means. In this study, we demonstrate the utility of {sup 14}C/C ratios to determine lichen age and growth rate in Cladina stygia (Fr.) Ahti collected from northwestern Alaska, USA. The average growth rate using {sup 14}C/C ratios was 6.5 mm {center_dot} yr{sup -1}, which was not significantly different from growth rates derived by Andreev's internode method (average = 6.2 mm {center_dot} yr{sup -1}); thus, suggesting the reliability of Andreev's simple field method for dating lichens. In addition, we found lichen growth rates appeared to differ with geographic location, yet did not seem related to ambient temperature and total precipitation.

For reporting year 2006, Los Alamos National Laboratory (LANL or the Laboratory) submitted Form R reports for lead as required under the Emergency Planning and Community Right-to-Know Act (EPCRA) Section 313. No other EPCRA Section 313 chemicals were used in 2006 above the reportable thresholds. This document was prepared to provide a description of the evaluation of EPCRA Section 313 chemical use and threshold determinations for LANL for calendar year 2006, as well as to provide background information about data included on the Form R reports. Section 313 of EPCRA specifically requires facilities to submit a Toxic Chemical Release Inventory Report (Form R) to the U.S. Environmental Protection Agency (EPA) and state agencies if the owners and operators manufacture, process, or otherwise use any of the listed toxic chemicals above listed threshold quantities. EPA compiles this data in the Toxic Release Inventory database. Form R reports for each chemical over threshold quantities must be submitted on or before July 1 each year and must cover activities that occurred at the facility during the previous year. In 1999, EPA promulgated a final rule on persistent bioaccumulative toxics (PBTs). This rule added several chemicals to the EPCRA Section 313 list of toxic …

The authors measured the absolute response of image plate (Fuji BAS SR2040) for electrons at energies between 100 keV to 4 MeV using an electron spectrometer. The electron source was produced from a short pulse laser irradiated on the solid density targets. This paper presents the calibration results of image plate Photon Stimulated Luminescence PSL per electrons at this energy range. The Monte Carlo radiation transport code MCNPX results are also presented for three representative incident angles onto the image plates and corresponding electron energies depositions at these angles. These provide a complete set of tools that allows extraction of the absolute calibration to other spectrometer setting at this electron energy range.

This report describes PowerLight Corporation's significant progress toward the reduction of installed costs for commercial-scale, rooftop PV systems.

Neutrino oscillations were first discovered by experiments looking at neutrinos coming from extra-terrestrial sources, namely the sun and the atmosphere, but we will be depending on earth-based sources to take many of the next steps in this field. This article describes what has been learned so far from accelerator-based neutrino oscillation experiments, and then describe very generally what the next accelerator-based steps are. In section 2 the article discusses how one uses an accelerator to make a neutrino beam, in particular, one made from decays in flight of charged pions. There are several different neutrino detection methods currently in use, or under development. In section 3 these are presented, with a description of the general concept, an example of such a detector, and then a brief discussion of the outstanding issues associated with this detection technique. Finally, section 4 describes how the measurements of oscillation probabilities are made. This includes a description of the near detector technique and how it can be used to make the most precise measurements of neutrino oscillations.

Interferometric fiber-optic links used in pulsed-power experiments are evaluated for accuracy in the presence of radiation fields which alter fiber transmission. Amplitude-modulated format (e.g., Mach-Zehnder) and phase-modulated formats are compared. Historically, studies of radiation effects on optical fibers have focused on degradation and recovery of the fibers transmission properties; such work is either in the context of survivability of fibers in catastrophic conditions or suitability of fibers installed for command and control systems within an experimental facility [1], [2]. In this work, we consider links used to transmit realtime diagnostic data, and we analyze the error introduced by radiation effects during the drive pulse. The result is increased uncertainties in key parameters required to unfold the sinusoidal transfer function. Two types of modulation are considered: amplitude modulation typical of a Mach-Zehnder (M-Z) modulator [3], and phase modulation, which offers more flexible demodulation options but relies on the spatiotemporal coherence of the light in the fiber. The M-Z link is shown schematically in Fig. 1, and the phase-modulated link is shown in Fig. 2. We present data from two experimental environments: one with intense, controlled radiation fields to simulate conditions expected at the next generation of pulsed-power facilities, and the second …

Though many enzymes can promote chemical reactions by tuning substrate properties purely through the electrostatic environment of a docking cavity, this strategy has proven challenging to mimic in synthetic host-guest systems. Here we report a highly-charged, water soluble, metal-ligand assembly with a hydrophobic interior cavity that thermodynamically stabilizes protonated substrates and consequently catalyzes the normally acidic hydrolysis of orthoformates in basic solution, with rate accelerations of up to 890-fold. The catalysis reaction obeys Michaelis-Menten kinetics, exhibits competitive inhibition, and the substrate scope displays size selectivity consistent with the constrained binding environment of the molecular host. Synthetic chemists have long endeavored to design host molecules capable of selectively binding slow-reacting substrates and catalyzing their chemical reactions. While synthetic catalysts are often site-specific and require certain properties of the substrate to insure catalysis, enzymes are often able to modify basic properties of the bound substrate such as pK{sub a} in order to enhance reactivity. Two common motifs used by nature to activate otherwise unreactive compounds are the precise arrangement of hydrogen-bonding networks and electrostatic interactions between the substrate and adjacent residues of the protein. Precise arrangement of hydrogen bonding networks near the active sites of proteins can lead to well-tuned pK{sub a}-matching, …

The purpose of this report is to provide a concise but comprehensive overview of Atmospheric Radiation Measurement Climate Research Facility instrumentation status. The report is divided into the following four sections: (1) new instrumentation in the process of being acquired and deployed, (2) existing instrumentation and progress on improvements or upgrades, (3) proposed future instrumentation, and (4) Small Business Innovation Research instrument development.

The sorption behavior of americium (Am), plutonium (Pu), neptunium (Np), and uranium (U) in perched Rainier Mesa tunnel water was investigated. Both volcanic zeolitized tuff samples and groundwater samples were collected from Rainier Mesa, Nevada Test Site, NV for a series of batch sorption experiments. Sorption in groundwater with and without the presence of dissolved organic matter (DOM) was investigated. Am(III) and Pu(IV) are more soluble in groundwater that has high concentrations of DOM. The sorption K{sub d} for Am(III) and Pu(IV) on volcanic zeolitized tuff was up to two orders of magnitude lower in samples with high DOM (15 to 19 mg C/L) compared to samples with DOM removed (< 0.4 mg C/L) or samples with naturally low DOM (0.2 mg C/L). In contrast, Np(V) and U(VI) sorption to zeolitized tuff was much less affected by the presence of DOM. The Np(V) and U(VI) sorption Kds were low under all conditions. Importantly, the DOM was not found to significantly sorb to the zeolitized tuff during these experiment. The concentration of DOM in groundwater affects the transport behavior of actinides in the subsurface. The mobility of Am(III) and Pu(IV) is significantly higher in groundwater with elevated levels of DOM resulting …

The ability to finely tune the size and shape of inorganic semiconducting nanocrystals is an area of great interest, as the more control one has, the more applications will be possible for their use. The first two basic shapes develped in nanocrystals were the sphere and the anistropic nanorod. the II_VI materials being used such as Cadmium Selenide (CdSe) and Cadmium Telluride (CdTe), exhibit polytypism, which allows them to form in either the hexagonally packed wurtzite or cubically packed zinc blende crystalline phase. The nanorods are wurtzite with the length of the rod growing along the c-axis. As this grows, stacking faults may form, which are layers of zinc blende in the otherwise wurtzite crystal. Using this polytypism, though, the first generation of branched crystals were developed in the form of the CdTe tetrapod. This is a nanocrystal that nucleates in the zincblend form, creating a tetrahedral core, on which four wurtzite arms are grown. This structure opened up the possibility of even more complex shapes and applications. This disseration investigates the advancement of branching control and further understanding the materials polytypism in the form of the stacking faults in nanorods.

A significant amount of progress has been achieved in the development of the novel vacuum distillation method described in the proposal. The process for the purification of Te was fully developed and characterized in a series of trials. The purification effect was confirmed with GDMS sample analysis and indicates the process yields very high purity Te metal. Results of this initial process study have been submitted for publication in the Proceedings of the SPIE and will be presented on August 28, 2007 at the SPIE Optics and Photonics 2007 conference in San Diego, CA. Concurrent to the development of the Te process, processes for the purification of Cd, Zn, and Mn have also progressed. The development of the processes for Cd and Zn are nearly complete, while the development of the process for Mn is still in its infancy. It is expected that a full characterization of the Cd process will be completed within the next quarter, followed by Zn. Parallel to those characterization studies, efforts will be made to further develop the Mn purification process. Zone melting work for Te and Cd has also been efforted as per the project work schedule. Initial trials have been completed and the …

Our report concerning advanced imaging and interpretation technology includes the development of theory, the implementation of laboratory experiments and the verification of results using field data. We investigated a reflectivity model for porous fluid-saturated reservoirs and demonstrated that the frequency-dependent component of the reflection coefficient is asymptotically proportional to the reservoir fluid mobility. We also analyzed seismic data using different azimuths and offsets over physical models of fractures filled with air and water. By comparing our physical model synthetics to numerical data we have identified several diagnostic indicators for quantifying the fractures. Finally, we developed reflectivity transforms for predicting pore fluid and lithology using rock-property statistics from 500 reservoirs in both the shelf and deep-water Gulf of Mexico. With these transforms and seismic AVO gathers across the prospect and its down-dip water-equivalent reservoir, fluid saturation can be estimated without a calibration well that ties the seismic. Our research provides the important additional mechanisms to recognize, delineate, and validate new hydrocarbon reserves and assist in the development of producing fields.

This third report in the series reviews possible safeguards approaches for new fast reactors in general, and the ABR in particular. Fast-neutron spectrum reactors have been used since the early 1960s on an experimental and developmental level, generally with fertile blanket fuels to “breed” nuclear fuel such as plutonium. Whether the reactor is designed to breed plutonium, or transmute and “burn” actinides depends mainly on the design of the reactor neutron reflector and the whether the blanket fuel is “fertile” or suitable for transmutation. However, the safeguards issues are very similar, since they pertain mainly to the receipt, shipment and storage of fresh and spent plutonium and actinide-bearing “TRU”-fuel. For these reasons, the design of existing fast reactors and details concerning how they have been safeguarded were studied in developing advanced safeguards approaches for the new fast reactors. In this regard, the design of the Experimental Breeder Reactor-II “EBR-II” at the Idaho National Laboratory (INL) was of interest, because it was designed as a collocated fast reactor with a pyrometallurgical reprocessing and fuel fabrication line – a design option being considered for the ABR. Similarly, the design of the Fast Flux Facility (FFTF) on the Hanford Site was studied, because …

This second report in a series of three reviews possible safeguards approaches for the new transuranic (TRU) fuel fabrication processes to be deployed at AFCF – specifically, the ceramic TRU (MOX) fuel fabrication line and the metallic (pyroprocessing) line. The most common TRU fuel has been fuel composed of mixed plutonium and uranium dioxide, referred to as “MOX”. However, under the Advanced Fuel Cycle projects custom-made fuels with higher contents of neptunium, americium, and curium may also be produced to evaluate if these “minor actinides” can be effectively burned and transmuted through irradiation in the ABR. A third and final report in this series will evaluate and review the advanced safeguards approach options for the ABR. In reviewing and developing the advanced safeguards approach for the new TRU fuel fabrication processes envisioned for AFCF, the existing international (IAEA) safeguards approach at the Plutonium Fuel Production Facility (PFPF) and the conceptual approach planned for the new J-MOX facility in Japan have been considered as a starting point of reference. The pyro-metallurgical reprocessing and fuel fabrication process at EBR-II near Idaho Falls also provided insight for safeguarding the additional metallic pyroprocessing fuel fabrication line planned for AFCF.

This report summarizes the work conducted from September 1, 2003 through December 31, 2007 on the project entitled Advanced Utility Mercury-Sorbent Field-Testing Program. The project covers the testing at the Detroit Edison St. Clair Plant and the Duke Power Cliffside and Buck Stations. The St. Clair Plant used a blend of subbituminous and bituminous coal and controlled the particulate emissions by means of a cold-side ESP. The Duke Power Stations used bituminous coals and controlled their particulate emissions by means of hot-side ESPs. The testing at the Detroit Edison St. Clair Plant demonstrated that mercury sorbents could be used to achieve high mercury removal rates with low injection rates at facilities that burn subbituminous coal. A mercury removal rate of 94% was achieved at an injection rate of 3 lb/MMacf over the thirty day long-term test. Prior to this test, it was believed that the mercury in flue gas of this type would be the most difficult to capture. This is not the case. The testing at the two Duke Power Stations proved that carbon- based mercury sorbents can be used to control the mercury emissions from boilers with hot-side ESPs. It was known that plain PACs did not have …

We conduct a detailed test of a recently developed technique, CAPloc, in recovering source parameters from a few stations against results from a large broadband network. The method uses a library of 1D Green’s functions which are broken into segments and matched to waveform observations with adjustable timing shifts. These shifts can be established by calibration against a distribution of well-located earthquake and assembled in tomographic images for predicting various phase-delays. Synthetics generated from 2D cross-sections through these models indicates that 1D synthetic waveforms are sufficient in modeling but simply shifted in time for hard-rock sites. This simplification allows the source inversion for both mechanism and location to be easily obtained by grid search. We test one-station mechanisms for 160 events against the array for both PAS and GSC which have data since 1960. While one station solutions work well (about 90%), joint solutions produce more reliable and defensible results. Inverting for both mechanism and location also works well except for certain difficult paths that cross deep basins or propagate along mountain ridges.

What is the point of developing new high-brightness light sources if beamline optics won't be available to realize the goals of nano-focusing and coherence preservation? That was one of the central questions raised during a workshop at the 2007 Advanced Light Source Users Meeting. Titled, 'Advanced X-Ray Optics Metrology for Nano-focusing and Coherence Preservation', the workshop was organized by Kenneth Goldberg and Valeriy Yashchuk (both of Lawrence Berkeley National Laboratory, LBNL), and it brought together industry representatives and researchers from Japan, Europe, and the US to discuss the state of the art and to outline the optics requirements of new light sources. Many of the presentations are viewable on the workshop website http://goldberg.lbl.gov/MetrologyWorkshop07/. Many speakers shared the same view of one of the most significant challenges facing the development of new high-brightness third and fourth generation x-ray, soft x-ray, and EUV light sources: these sources place extremely high demands on the surface quality of beamline optics. In many cases, the 1-2-nm surface error specs that define the outer bounds of 'diffraction-limited' quality are beyond the reach of leading facilities and optics vendors. To focus light to 50-nm focal spots, or smaller, from reflective optics and to preserve the high coherent …

This year's meeting focused on the latest advances in new DNA sequencing technologies and the applications of genomics to disease areas in biology and biomedicine. Daytime plenary sessions highlighted cutting-edge research in areas such as complex genetic diseases, comparative genomics, medical sequencing, massively parallel DNA sequencing, and synthetic biology. Technical approaches being developed and utilized in contemporary genomics research were presented during evening concurrent sessions. Also, as in previous years, poster sessions bridged the morning and afternoon plenary sessions. In addition, for the third year in a row, the Advances in Genome Biology and Technology (AGBT) meeting was preceded by a pre-meeting workshop that aimed to provide an introductory overview for trainees and other meeting attendees. This year, speakers at the workshop focused on next-generation sequencing technologies, including their experiences, findings, and helpful advise for others contemplating using these platforms in their research. Speakers from genome centers and core sequencing facilities were featured and the workshop ended with a roundtable discussion, during which speakers fielded questions from the audience.

Power plant-heated lakes are characterized by a temperature gradient in the thermal plume originating at the discharge of the power plant and terminating at the water intake. The maximum water temperature discharged by the power plant into the lake depends on the power generated at the facility and environmental regulations on the temperature of the lake. Besides the observed thermal plume, cloud-like thermal cells (convection cell elements) are also observed on the water surface. The size, shape and temperature of the convection cell elements depends on several parameters such as the lake water temperature, wind speed, surfactants and the depth of the thermocline. The Savannah River National Laboratory (SRNL) and Clemson University are collaborating to determine the applicability of laboratory empirical correlations between surface heat flux and thermal convection intensity. Laboratory experiments at Clemson University have demonstrated a simple relationship between the surface heat flux and the standard deviation of temperature fluctuations. Similar results were observed in the aerial thermal imagery SRNL collected at different locations along the thermal plume and at different elevations. SRNL will present evidence that the results at Clemson University are applicable to cooling lakes.

As part of the proficiency training for the Radiological Mapping mission of the Aerial Measuring System (AMS), a survey team from the Remote Sensing Laboratory-Nellis (RSL-Nellis) conducted an aerial radiological survey on December 11-12, 2007, with the purpose of mapping natural radiation background and locating any man-made radioactive sources. The survey covered 19.4 square miles (9.2 square miles over the downtown area of the City of North Las Vegas and 10.2 square miles over the Las Vegas Motor Speedway [LVMS]). The flight lines over the surveyed areas are presented in Figures 1 and 2. A total of four 2.5-hour-long flights were performed at an altitude of 150 ft above ground level (AGL) with 300 ft of flight line spacing. Water line and test line flights were conducted over the Lake Mead and Government Wash areas to ensure quality control of the data. The data were collected by the AMS data acquisition system-REDAR V using an array of twelve 2-inch x 4-inch x 16-inch sodium iodide (NaI) detectors flown on-board a twin-engine Bell 412 helicopter. Data in the form of gamma energy spectra were collected continually (every second) over the course of the survey and were geo-referenced using a differential Global …

An aerial radiological survey was conducted over the 16 square-mile (~41 square-kilometer) area surrounding the Portsmouth Gaseous Diffusion Plant. The survey was performed in August 2007 utilizing a large array of helicopter mounted sodium iodide detectors. The purpose of the survey was to update the previous radiological survey levels of the environment and surrounding areas of the plant. A search for a missing radium-226 source was also performed. Implied exposure rates, man-made activity, and excess bismuth-214 activity, as calculated from the aerial data are presented in the form of isopleth maps superimposed on imagery of the surveyed area. Ground level and implied aerial exposure rates for nine specific locations are compared. Detected radioisotopes and their associated gamma ray exposure rates were consistent with those expected from normal background emitters. At specific plant locations described in the report, man-made activity was consistent with the operational histories of the location. There was no spectral activity that would indicate the presence of the lost source.

Sayers and Kachanov (1991) defined crack-influence parameters that are shown to be directly related to Thomsen (1986) weak-anisotropy seismic parameters for fractured reservoirs when the crack/fracture density is small enough. These results are then applied to the problem of seismic wave propagation in polar (i.e., non-isotropic) reservoirs having HTI seismic wave symmetry due to the presence of aligned vertical fractures and resulting in azimuthal seismic wave symmetry at the earth's surface. The approach presented suggests one method of inverting for fracture density from wave-speed data. It is also observed that the angular location {theta}{sub ex} of the extreme value (peak or trough) of the quasi-SV-wave speed for VTI occurs at an angle determined approximately by the formula tan{sup 2} {theta}{sub ex} {approx_equal} tan {theta}{sub m} = [(c{sub 33} - c{sub 44})/(c{sub 11}-c{sub 44})]{sup 1/2}, where {theta}{sub m} is an angle determined directly (as shown) from the c{sub ij} elastic stiffnesses, whenever these are known from either quasi-static or seismic wave measurements. Alternatively, {theta}{sub ex} is given in terms of the Thomsen seismic anisotropy parameters by tan {theta}{sub ex} {approx_equal} ([v{sub p}{sup 2}(0)-v{sub s}{sup 2}(0)]/[(1 + 2{epsilon})v{sub p}{sup 2}(0)-v{sub s}{sup 2}(0)]){sup 1/4}, where {epsilon} = (c{sub 11}-c{sub 33})/2c{sub 33}, v{sub p}{sup …