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Effects of pressure and saturation on seismic velocities and impedance measurements

Description: Two synthetic data sets were examined to study the possible methods for distinguishing the effects of changes in saturation, and changes in pore pressure, on seismic velocity and impedance measurements. The results show that the results obtained previously on the dependence of laboratory velocity data on changes in saturation carry over without change to the data in these data sets. The assumption in this case is that the only data available are the seismic velocities. This situation can arise … more
Date: January 18, 2001
Creator: Berryman, James G.
Item Type: Refine your search to only Report
open access

Sputter Deposition of Metallic Sponges

Description: Metallic films are grown with a sponge-like morphology in the as-deposited condition using planar magnetron sputtering. The morphology of the deposit is characterized by metallic continuity in three dimensions with continuous porosity on the sub-micron scale. The stabilization of the metallic sponge is directly correlated with a limited range for the sputter deposition parameters of working gas pressure and substrate temperature. This sponge-like morphology augments the features as generally un… more
Date: January 18, 2002
Creator: Jankowski, Alan Frederic & Hayes, Jeffrey P.
Item Type: Refine your search to only Article
open access

Magnetic Random Access Memory (MRAM) Device Development

Description: The recent discovery of materials that have anomalous magneto-resistive properties has generated renewed commercial interest in metal-based fast memory storage as an alternative to the currently used semiconductor-based devices. One particularly promising ternary alloy, fabricated at LLNL, appeared to have exceptional field response. This proposal extended the investigation of this class of materials by examining the scaling properties of test structures made from this material that could defin… more
Date: January 18, 2000
Creator: Cerjan, C & Law, B P
Item Type: Refine your search to only Report
open access

Manufacture of Large-Aperture Diffractive Optics and Ultrathin Optics for High-Power Laser and Space Applications

Description: We have developed equipment and technology for fabricating submicron pitch, high-efficiency diffraction gratings over meter-scale apertures that are used for pulse compression in ultrafast systems around the world. We have also developed wet-etch figuring (WEF) to generate arbitrary continuous contours on ultrathin glass substrates in a closed loop process. The current and future states of these technologies will be discussed.
Date: January 18, 2002
Creator: Britten, J A
Item Type: Refine your search to only Article
open access

Structured Surface Grid Generation on Boundary Represented Geometry

Description: Generation of surface meshes is the first step in many grid generation processes. For the generation of block-structured meshes, structured surface meshes have to be generated first. This paper investigates the problem of generating a structured surface mesh across multiple surface patches on an object with the boundary representation and relates the problem to other commonly encountered issues in CAD/CAM. It describes a method for solving the problem. This method is based on initial surface co… more
Date: January 18, 2002
Creator: Chou, J J
Item Type: Refine your search to only Article
open access

Disposition Options for Hanford Site K-Basin Spent Nuclear Fuel Sludge

Description: This report provides summary-level information about a group of options that have been identified for the disposition of spent-nuclear-fuel sludge in the K-Basins at the Hanford Site. These options are representative of the range of likely candidates that may be considered for disposition of the sludge. The product of each treatment option would be treated sludge that would meet waste acceptance requirements for disposal as transuranic (TRU) waste at the Waste Isolation Pilot Plant (WIPP).
Date: January 18, 2004
Creator: Mellinger, George B.; Delegard, Calvin H.; Gerber, Mark A.; Naft, Barry N.; Schmidt, Andrew J. & Walton, Terry L.
Item Type: Refine your search to only Report
open access

Tank Leak Experiment at the Mock Tank Site, 200 East Area: Electrical Resistance Tomography-Preliminary Results

Description: Electrical resistance measurements were used to monitor several releases of brine from the Mock Tank Test site at the 200 East Area. Three different methods were used to analyze the data: (1) a simple average of the raw data was used as an indicator of the presence/absence of a leak, (2) tomography of the region beneath the tank using data from steel-cased borehole, and (3) tomography of the region beneath the tank using data from vertical electrode arrays. Each of these methods was able to det… more
Date: January 18, 2002
Creator: Ramirez, A; Daily, W & Binley, A
Item Type: Refine your search to only Report
open access

Focus Magnet and Vessel Interface Issues in HYLIFE-II

Description: The present Heavy Ion Driver design for HYLIFE-II calls for 96 beams from each side, or a total of 192 beams. The beams are separated from each other, at present, by an angle of 4.25 degrees. This report shows the focus magnet locations and a magnet build that leads to the minimum angle of 4.25 degrees between beams. Beam line and first wall shielding for the oscillating flow version of HYLIFE-II is accomplished by a series of horizontal and vertical jets. Ideally the horizontal jets would not … more
Date: January 18, 2000
Creator: House, P A
Item Type: Refine your search to only Report
open access

Fiber Laser Front Ends for High-Energy Short Pulse Lasers

Description: We are developing an all fiber laser system optimized for providing input pulses for short pulse (1-10ps), high energy ({approx}1kJ) glass laser systems. Fiber lasers are ideal solutions for these systems as they are highly reliable and once constructed they can be operated with ease. Furthermore, they offer an additional benefit of significantly reduced footprint. In most labs containing equivalent bulk laser systems, the system occupies two 4'x8' tables and would consist of 10's if not a 100 … more
Date: January 18, 2005
Creator: Dawson, J W; Liao, Z M; Mitchell, S; Messerly, M; Beach, R; Jovanovic, I et al.
Item Type: Refine your search to only Article
open access

Towards p-type doping of ZnO by ion implantation

Description: Zinc oxide is a very attractive material for a range of optoelectronic devices including blue light-emitting diodes and laser diodes. Though n-type doping has been successfully achieved, p-type doing of ZnO is still a challenge that must be overcome before p-n junction devices can be realized. Ion implantation is widely used in the microelectronics industry for selective area doping and device isolation. Understanding damage accumulation and recrystallization processes is important for achievin… more
Date: January 18, 2005
Creator: Coleman, V; Tan, H H; Jagadish, C; Kucheyev, S; Phillips, M & Zou, J
Item Type: Refine your search to only Article
open access

Chemistry and Processing of Nanostructured Materials

Description: Nanostructured materials can be formed through the sol-gel polymerization of inorganic or organic monomer systems. For example, a two step polymerization of tetramethoxysilane (TMOS) was developed such that silica aerogels with densities as low as 3 kg/m{sup 3} ({approx} two times the density of air) could be achieved. Organic aerogels based upon resorcinol-formaldehyde and melamine-formaldehyde can also be prepared using the sol-gel process. Materials of this type have received significant att… more
Date: January 18, 2002
Creator: Fox, G A; Baumann, T F; Hope-Weeks, L J & Vance, A L
Item Type: Refine your search to only Report
open access

Addressing the Need for Alternative Transportation Fuels: The Joint BioEnergy Institute

Description: Today, carbon-rich fossil fuels, primarily oil, coal, and natural gas, provide 85% of the energy consumed in the U.S. As world demand increases, oil reserves may become rapidly depleted. Fossil fuel use increases CO{sub 2} emissions and raises the risk of global warming. The high energy content of liquid hydrocarbon fuels makes them the preferred energy source for all modes of transportation. In the U.S. alone, transportation consumes >13.8 million barrels of oil per day and generates 0.5 gi… more
Date: January 18, 2008
Creator: Blanch, Harvey; Adams, Paul; Andrews-Cramer, Katherine; Frommer, Wolf; Simmons, Blake & Keasling, Jay
Item Type: Refine your search to only Article
open access

NCSX Plasma Heating Methods

Description: The National Compact Stellarator Experiment (NCSX) has been designed to accommodate a variety of heating systems, including ohmic heating, neutral beam injection, and radio-frequency (rf). Neutral beams will provide one of the primary heating methods for NCSX. In addition to plasma heating, neutral beams are also expected to provide a means for external control over the level of toroidal plasma rotation velocity and its profile. The experimental plan requires 3 MW of 50-keV balanced neutral bea… more
Date: January 18, 2008
Creator: H.W. Kugel, D. Spong, R. Majeski and M. Zarnstorff
Item Type: Refine your search to only Report
open access

Settling of Spinel in a High-Level Waste Glass Melter

Description: High-level nuclear waste is being vitrified, i.e., converted to a durable glass that can be stored in a safe repository for hundreds of thousands of years. Waste vitrification is accomplished in reactors called melters to which the waste is charged together with glass-forming additives. The mixture is electrically heated to a temperature as high as 1150?C (or even higher in advanced melters) to create a melt that becomes glass on cooling. This process is slow and expensive. Moreover, the melter… more
Date: January 18, 2002
Creator: Hrma, Pavel R.; Schill, Pert & Nemec, Lubomir
Item Type: Refine your search to only Report
open access

Supra-bubble regime for laser acceleration of coldelectron beams in tenuous plasma

Description: Relativistic electrons can be accelerated by an ultraintense laser pulse in the "supra-bubble" regime, that is, in the blow-out regime ahead of the plasma bubble (as opposed to the conventional method, when particles remain inside the bubble). The acceleration is caused by the ponderomotive force of the pulse, via the so-called snow-plow mechanism. The maximum energy gain, Δγ ~ γg a, is attained when the particle Lorentz factor γ is initially about γg/a, where γg is the pulse group speed Lorent… more
Date: January 18, 2009
Creator: V.I. Geyko, I.Y. Dodin, and N.J. Fisch G.M. Fraiman
Item Type: Refine your search to only Report
open access

DNA repair efficiency in germ cells and early mouse embryos and consequences for radiation-induced transgenerational genomic damage

Description: Exposure to ionizing radiation and other environmental agents can affect the genomic integrity of germ cells and induce adverse health effects in the progeny. Efficient DNA repair during gametogenesis and the early embryonic cycles after fertilization is critical for preventing transmission of DNA damage to the progeny and relies on maternal factors stored in the egg before fertilization. The ability of the maternal repair machinery to repair DNA damage in both parental genomes in the fertilizi… more
Date: January 18, 2009
Creator: Marchetti, Francesco & Wyrobek, Andrew J.
Item Type: Refine your search to only Article
open access

Isothermal Martensitic and Pressure-Induced Delta to Alpha-Prime Phase Transformations in a Pu-Ga Alloy

Description: A well-homogenized Pu-2 at.% Ga alloy can be retained in the metastable face-centered cubic {delta} phase at room temperature. Ultimately, this metastable {delta} phase will decompose via a eutectoid transformation to the thermodynamically stable monoclinic {alpha} phase and the intermetallic compound Pu{sub 3}Ga over a period of approximately 10,000 years [1]. In addition, these low solute-containing {delta}-phase Pu alloys are metastable with respect to an isothermal martensitic phase transfo… more
Date: January 18, 2008
Creator: Schwartz, A J; Wall, M A; Farber, D L; Moore, K T & Blobaum, K M
Item Type: Refine your search to only Article
open access

Bi3+ Luminescence in ABiO2Cl (A = Sr, Ba) and BaBiO2Br

Description: Trivalent bismuth luminescence is reported in three Sillenbismuth oxyhalide phases, SrBiO2Cl, BaBiO2Cl, and BaBiO2Br. Thesecompounds exhibit Bi 6s6->6 s2 emission under UV and X-ray radiation.At room temperature, BaBiO2Cl shows the most intense light emission, withspectral and decay properties similar to those found in Bi4Ge3O12 (BGO).At low temperatures, each phase show an increase in the photoluminescenceintensities and a narrowing of the emission peaks. In contrast to thetemperature dependen… more
Date: January 18, 2007
Creator: Porter-Chapman, Yetta D.; Bourret-Courchesne, Edith E. & Derenzo,Stephen E.
Item Type: Refine your search to only Article
open access

Hydrogen adsorption on Ru(001) studied by Scanning TunnelingMicroscopy

Description: The adsorption of hydrogen on Ru(001) was studied by scanning tunneling microscopy at temperatures around 50 K. Hydrogen was found to adsorb dissociatively forming different ordered structures as a function of coverage. In order of increasing coverage {theta} in monolayers (ML) these were ({radical}3 x {radical}3)r30{sup o} at {theta} = 0.3 ML; (2 x 1) at {theta} = 0.50 ML, (2 x 2)-3H at {theta} = 0.75, and (1 x 1) at {theta} = 1.00. Some of these structures were observed to coexist at intermed… more
Date: January 18, 2008
Creator: Tatarkhanov, Mous; Rose, Franck; Fomin, Evgeny; Ogletree, D.Frank & Salmeron, Miquel
Item Type: Refine your search to only Article
open access

Development of Solar Grade (SoG) Silicon

Description: The rapid growth of the photovoltaics (PV) industry is threatened by the ongoing shortage of suitable solar grade (SoG) silicon. Until 2004, the PV industry relied on the off spec polysilicon from the electronics industry for feedstock. The rapid growth of PV meant that the demand for SoG silicon predictably surpassed this supply. The long-term prospects for PV are very bright as costs have come down, and efficiencies and economies of scale make PV generated electricity ever more competitive wi… more
Date: January 18, 2008
Creator: Joyce, David B & Schmid, Frederick
Item Type: Refine your search to only Report
open access

State-Resolved Dynamics of the CN(B2Sigma+) and CH(A2Delta)Excited Products Resulting from the VUV Photodissociation of CH3CN

Description: Fourier transform visible spectroscopy, in conjunction withVUV photons produced by a synchrotron, is employed to investigate thephotodissociation of CH3CN. Emission is observed from both theCN(B2Sigma+ - X2Sigma+) and CH(A2Delta - X2PI) transitions; only theformer is observed in spectra recorded at 10.2 and 11.5 eV, whereas bothare detected in the 16 eV spectrum. The rotational and vibrationaltemperatures of both the CN(B2Sigma+) and CH(A2Delta) radical productsare derived using a combination o… more
Date: January 18, 2007
Creator: Howle, Chris R.; Arrowsmith, Alan N.; Chikan, Viktor & Leone,Stephen R.
Item Type: Refine your search to only Article
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