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Material dynamics at extreme pressures and strain rates

Description: Solid state experiments at extreme pressures (10-100 GPa) and strain rates ({approx}10{sup 6}-10{sup 8}s{sup -1}) are being developed on high-energy laser facilities, and offer the possibility for exploring new regimes of materials science. [Re 2004] These extreme solid-state conditions can be accessed with either shock loading or with quasi-isentropic ramped pressure pulses being developed on the Omega laser. [Ed 2004] Velocity interferometer measurements establish the high strain rates. Const… more
Date: August 25, 2004
Creator: Remington, Bruce A.; Cavallo, Rob M.; Edwards, Michael J.; Ho, David D.; Lasinski, Barbara F.; Lorenz, Karl T. et al.
Item Type: Refine your search to only Article
open access

Large plasma pressure perturbations and radial convective transport in a tokamak

Description: Strongly localized plasma structures with large pressure inhomogeneities (such as plasma blobs in the scrape-off-layer (SOL)/shadow regions, pellet clouds, ELMs) observed in the tokamaks, stellarators and linear plasma devices. Experimental studies of these phenomena reveal striking similarities including more convective rather than diffusive radial plasma transport. We suggest that rather simple models can describe many essentials of blobs, ELMs, and pellet clouds dynamics. The main ingredient… more
Date: February 4, 2004
Creator: Krasheninnikov, S.; Ryutov, D. & Yu, G.
Item Type: Refine your search to only Article
open access

In-situ Diffraction Studies of Shock Compressed Single-Crystal Iron

Description: The technique of in-situ wide angle diffraction has been used to study materials such as Si and Cu. We have extended our studies of shocked single crystal materials to include Fe (001) that is shock compressed by direct laser irradiation using the OMEGA and Janus lasers. A series of experiments was conducted in Fe at pressures above the Hugoniot Elastic Limit. Transient x-ray was used to record the response of multiple lattice planes simultaneously. This technique of wide-angle diffraction prov… more
Date: July 16, 2004
Creator: Kalantar, D H; Colvin, J D; Eggert, J; Lorenzana, H; Stolken, J; Hawreliak, J et al.
Item Type: Refine your search to only Article
open access

Monolithic Nickel (II) Oxide Aerogels Using an Organic Epoxide: The Importance of the Counter Ion

Description: The synthesis and characterization of nickel (II) oxide aerogel materials prepared using the epoxide addition method is described. The addition of the organic epoxide propylene oxide to an ethanolic solution of NiCl{sub 2} 6H{sub 2}O resulted in the formation of an opaque light green monolithic gel and subsequent drying with supercritical CO{sub 2} gave a monolithic aerogel material of the same color. This material has been characterized using powder X-ray diffraction, electron microscopy, elem… more
Date: January 13, 2004
Creator: Gash, A. E.; Satcher, J. H. & Simpson, R. L.
Item Type: Refine your search to only Article
open access

Mass by Energy Loss Quantitation as a Practical Sub-Microgram Balance

Description: A simple device integrating a thin film support and a standard microcentrifuge tube can be used for making solutions of accurately known concentration of any organic compound in a single step, avoiding serial dilution and the use of microgram balances. Nanogram to microgram quantities of organic material deposited on the thin film are quantified by ion energy loss and transferred to the microcentrifuge tube with high recovery.
Date: September 28, 2004
Creator: Palmblad, M; Bench, G & Vogel, J S
Item Type: Refine your search to only Article
open access

COG validation: SINBAD Benchmark Problems

Description: We validated COG, a 3D Monte Carlo radiation transport code, against experimental data and MNCP4C simulations from the Shielding Integral Benchmark Archive Database (SINBAD) compiled by RSICC. We modeled three experiments: the Osaka Nickel and Aluminum sphere experiments conducted at the OKTAVIAN facility, and the liquid oxygen experiment conducted at the FNS facility. COG results are in good agreement with experimental data and generally within a few % of MCNP results. There are several possib… more
Date: February 23, 2004
Creator: Lent, E M; Sale, K E; Buck, R M & Descalle, M
Item Type: Refine your search to only Report
open access

Synthesis of Novel Extended Phases of Molecular Solids at High Pressures and Temperatures

Description: This study is for in-situ investigation of chemical bonding and molecular structure of low z-elements and simple molecular solids at high pressures and temperatures using 3rd-generation synchrotron x-ray diffraction. To understand the contribution of the empty d-electron orbital of Mg in relation to the formation of molecular solids like MgO, which is one of the important Earth lower mantle materials and MgB{sub 2}, which has recently been the focus of intense superconducting material research,… more
Date: March 30, 2004
Creator: Yoo, C; Evans, W & Cynn, H
Item Type: Refine your search to only Report
open access

Insights into the Dynamic Response of Tunnels in Jointed Rocks

Description: Tunnels in jointed rocks can be subjected to severe dynamic loads because of rock bursts, coal bumps, and large earthquakes. A series of 3-dimensional simulations was performed, based on discrete element analysis to gain insights into the parameters that influence the response of such tunnels. The simulations looked at the effect of joint set orientation, the effect of joint spacing, the effect of pulse shape for a given displacement, and the influence of using rigid versus deformable blocks in… more
Date: November 1, 2004
Creator: Heuze, F E
Item Type: Refine your search to only Article
open access

Small Wind Electric Systems: An Idaho Consumer's Guide (Revised)

Description: Small Wind Electric Systems: An Idaho Consumer's Guide provides consumers with information to help them determine whether a small wind electric system can provide all or a portion of the energy they need for their home or business based on their wind resource, energy needs, and their economics. Topics discussed in the guide include how to make a home more energy efficient, how to choose the correct turbine size, the parts of a wind electric system, how to determine whether enough wind resource … more
Date: August 1, 2004
Item Type: Refine your search to only Text
open access

The 1997/98 El Nino: A Test for Climate Models

Description: Version 3 of the Hadley Centre Atmospheric Model (HadAM3) has been used to demonstrate one means of comparing a general circulation model with observations for a specific climate perturbation, namely the strong 1997/98 El Nino. This event was characterized by the collapse of the tropical Pacific's Walker circulation, caused by the lack of a zonal sea surface temperature gradient during the El Nino. Relative to normal years, cloud altitudes were lower in the western portion of the Pacific and hi… more
Date: March 5, 2004
Creator: Lu, R; Dong, B; Cess, R D & Potter, G L
Item Type: Refine your search to only Article
open access

Toward understanding environmental effects in SDSS clusters

Description: We find clusters and superclusters of galaxies using the Data Release 1 of the Sloan Digital Sky Survey. We determine the luminosity function of clusters and find that clusters in a high-density environment have a luminosity a factor of {approx}5 higher than in a low-density environment. We also study clusters and superclusters in numerical simulations. Simulated clusters in a high-density environment are also more massive than those in a low-density environment. Comparison of the density distr… more
Date: November 1, 2004
Creator: Einasto, Jaan; Tago, E.; Einasto, M.; Saar, E.; Suhhonenko, I.; Heinamaki, P. et al.
Item Type: Refine your search to only Article
open access

EVALUATING ENVIRONMENTAL DECISION SUPPORT TOOLS.

Description: Effective contaminated land management requires a number of decisions addressing a suite of technical, economic, and social concerns. These concerns include human health risks, ecological risks, economic costs, technical feasibility of proposed remedial actions, and the value society places on clean-up and re-use of formerly contaminated lands. Decision making, in the face of uncertainty and multiple and often conflicting objectives, is a vital and challenging role in environmental management t… more
Date: October 1, 2004
Creator: SULLIVAN, T.
Item Type: Refine your search to only Report
open access

Seismic Response Prediction of Nupec's Field Model Tests of Npp Structures With Adjacent Building Effect.

Description: As part of a verification test program for seismic analysis computer codes for Nuclear Power Plant (NPP) structures, the Nuclear Power Engineering Corporation (NUPEC) of Japan has conducted a series of field model tests to address the dynamic cross interaction (DCI) effect on the seismic response of NPP structures built in close proximity to each other. The program provided field data to study the methodologies commonly associated with seismic analyses considering the DCI effect. As part of a c… more
Date: March 4, 2004
Creator: Xu, J.; Hofmayer, C. & Ali, S.
Item Type: Refine your search to only Article
open access

Analysis and Comparison of Test Results from the Small Wind Research Turbine Test Project: Preprint

Description: Most small wind turbines furl (yaw or tilt out of the wind) as a means of limiting power and rotor speeds in high winds. The Small Wind Research Turbine (SWRT) testing project was initiated in 2003 with the goal of better characterizing both small wind turbine loads (including thrust) and dynamic behavior, specifically as they relate to furling. The main purpose of the testing was to produce high-quality data sets for model development and validation and to help the wind industry further their … more
Date: November 1, 2004
Creator: Corbus, D. & Prascher, D.
Item Type: Refine your search to only Article
open access

A Tightly Coupled Particle-Fluid Model for DNA-Laden Flows in Complex Microscale Geometries

Description: We present a stable and convergent method for the computation of flows of DNA-laden fluids in microchannels with complex geometry. The numerical strategy combines a ball-rod model representation for polymers tightly coupled with a projection method for incompressible viscous flow. We use Cartesian grid embedded boundary methods to discretize the fluid equations in the presence of complex domain boundaries. A sample calculation is presented showing flow through a packed array microchannel in 2D.
Date: November 18, 2004
Creator: Trebotich, D; Miller, G H; Colella, P; Graves, D T; Martin, D F & Schwartz, P O
Item Type: Refine your search to only Article
open access

Rapid Qualitative Risk Assessment for Contaminant Leakage From Coal Seams During Underground Coal Gasification and CO2 Injection

Description: One of the major risks associated with underground coal gasification is contamination of local aquifers with a variety of toxic compounds. It is likely that the rate, volume, extent, and concentrations of contaminant plumes will depend on the local permeability field near the point of gasification. This field depends heavily on the geological history of stratigraphic deposition and the specifics of stratigraphic succession. Some coals are thick and isolated, whereas others are thinner and more … more
Date: July 2, 2004
Creator: Friedmann, S J
Item Type: Refine your search to only Report
open access

Theoretical study of the electronic states of Nb4, Nb5 clusters and their anions (Nb4?, Nb5?)

Description: Geometries and energy separations of the various low-lying electronic states of Nb{sub n} and Nb{sub n}{sup -} (n = 4, 5) clusters with various structural arrangements have been investigated. The complete active space multi-configuration self-consistent field (CASMCSCF) method followed by multi-reference singles and doubles configuration interaction (MRSDCI) calculations that included up to 52 million configuration spin functions have been used to compute several electronic states of these clus… more
Date: May 6, 2004
Creator: Balasubramanian, K & Majumdar, D
Item Type: Refine your search to only Article
open access

ESTIMATES FOR RELEASE OF RADIONUCLIDES FROM POTENTIALLY CONTAMINATED CONCRETE AT THE HADDAM NECK NUCLEAR PLANT.

Description: Decommissioning of the Haddam Neck Nuclear Power Plant operated by Connecticut Yankee is in progress. Figure 1 shows a schematic of the Containment Building and Spent Fuel Pool (SFP) Building. Consideration is being given to leaving some subsurface concrete from the Containment, Spent Fuel and certain other buildings in place following NRC license termination. Characterization data of most of these structures show small amounts of residual contamination. The In-Core Sump area of the Containment… more
Date: September 15, 2004
Creator: SULLIVAN, T.
Item Type: Refine your search to only Report
open access

Formulation of the Linear Response Theory in Relativistic LAPW Method. Calculation of Forces in Alpha-Pu

Description: Linear-response (LR) theory in combination with the first-principles band structure codes allows to calculate phonons in an efficient way. In this report a formalism which enables us to apply LR theory within an all-electron framework utilizing the relativistic full-potential linearized augmented plane-wave (RFLAPW) method is presented. As first part, the equations for the calculations of the atomic forces are given and they are used for the calculation of forces in {alpha}-Pu. As a second step… more
Date: January 8, 2004
Creator: Kutepov, A L
Item Type: Refine your search to only Report
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