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Effect of Ethanol and Methyl-tert-Butyl Ether on Monoaromatic Hydrocarbon Biodegradation: Response Variability for Different Aquifer Materials Under Various Electron-Accepting Conditions

Description: Aquifer microcosms were used to determine how ethanol and methyl-tert-butyl ether (MtBE) affect monoaromatic hydrocarbon degradation under different electron-accepting conditions commonly found in contaminated sites experiencing natural attenuation. Response variability was investigated by using aquifer material from four sites with different exposure history. The lag phase prior to BTEX (benzene, toluene, ethylbenzene, and xylenes) and ethanol degradation was typically shorter in microcosms wi… more
Date: October 6, 2003
Creator: Ruiz-Aguilar, G L; Fernandez-Sanchez, J M; Kane, S R; Kim, D & Alvarez, P J
Item Type: Refine your search to only Article
open access

Investigating Sources of Toxicity in Stormwater: Algae Mortality in Runoff Upstream of the Lawrence Livermore National Laboratory

Description: A source evaluation case study is presented for observations of algae toxicity in an intermittent stream passing through the Lawrence Livermore National Laboratory near Livermore, California. A five-step procedure is discussed to determine the cause of water toxicity problems and to determine appropriate environmental management practices. Using this approach, an upstream electrical transfer station was identified as the probable source of herbicides causing the toxicity. In addition, an analyt… more
Date: October 6, 2003
Creator: Campbell, C G; Folks, K; Mathews, S & Martinelli, R
Item Type: Refine your search to only Article
open access

Facilities for Development of Modified Nitride-Based Fuel Pellets

Description: Facilities to support development of modified nitride-based reactor fuel pellets have been activated and are now in operation at Lawrence Livermore National Laboratory. These facilities provide the controls and monitored laboratory conditions required to produce, evaluate, and verify quality of the nitride-based product required for this fuel application. By preserving the high melting point, high thermal conductivity, and high actinide density properties of nitride fuel while enhancing stoichi… more
Date: October 22, 2003
Creator: Meier, T.; Ebbinghaus, B. & Choi, J.
Item Type: Refine your search to only Article
open access

Nuclear structure with accurate chiral perturbation theory nucleon-nucleon potential: Application to 6Li and 10B

Description: The authors calculate properties of A = 6 system using the accurate charge-dependent nucleon-nucleon (NN) potential at fourth order of chiral perturbation theory. By application of the ab initio no-core shell model (NCSM) and a variational calculation in the harmonic oscillator basis with basis size up to 16 {h_bar}{Omega} they obtain the {sup 6}Li binding energy of 28.5(5) MeV and a converged excitation spectrum. Also, they calculate properties of {sup 10}B using the same NN potential in a bas… more
Date: October 14, 2003
Creator: Navratil, P & Caurier, E
Item Type: Refine your search to only Report
open access

Block Matching for Object Tracking

Description: Models which describe road traffic patterns can be helpful in detection and/or prevention of uncommon and dangerous situations. Such models can be built by the use of motion detection algorithms applied to video data. Block matching is a standard technique for encoding motion in video compression algorithms. We explored the capabilities of the block matching algorithm when applied for object tracking. The goal of our experiments is two-fold: (1) to explore the abilities of the block matching al… more
Date: October 13, 2003
Creator: Gyaourova, A; Kamath, C & Cheung, S
Item Type: Refine your search to only Report
open access

Determining the Equation of State Isentrope in an Isochoric Heated Plasma

Description: A novel method for determining the equation-of-state (EOS) along the release isentrope in an isochoric (constant volume) heated plasma is presented. The sensitivity of this approach is demonstrated using two different equation-of-state models for a solid density, 10 eV expanding Al plasma. Determining the material EOS data is validated to pressures near 80 Mbar, much higher than current isentropic compression experiments allow. Limitations at high temperature (T{sub e} {ge} 100 eV) due to the f… more
Date: October 16, 2003
Creator: Foord, M. E.; Reisman, D. B. & Springer, P. T.
Item Type: Refine your search to only Article
open access

Future Directions for Thermal Distribution Standards

Description: This report details development paths for advanced versions of ASHRAE Standard 152, Method of Test for Determining the Design and Seasonal Efficiencies of Residential Thermal Distribution Efficiency. During the course of conversations within the ASHRAE committee responsible for developing the standard (SPC152P), three areas of development for Standard 152 were proposed: (1) extend the scope of the standard to include thermal comfort variables; (2) extend the scope of the standard to include sma… more
Date: October 31, 2003
Creator: Andrews, John W.
Item Type: Refine your search to only Report
open access

A neutron sensor based on synthetic single crystal diamond

Description: We report the first neutron data for a single crystal Chemical Vapor Deposition (CVD) diamond sensor. Results are presented for 2.5, 14.1, and 14.9 MeV incident neutrons. We show that the energy resolution for 14.1 MeV neutrons is at least 2.9% (as limited by the energy spread of the incident neutrons), and perhaps as good as 0.4% (as extrapolated from high resolution {alpha} particle data). This result could be relevant to fusion neutron spectroscopy at machines like the International Thermonu… more
Date: October 17, 2003
Creator: Schmid, G. J.; Koch, J. A.; Lerche, R. A. & Moran, M. J.
Item Type: Refine your search to only Article
open access

Statistical techniques to find similar objects in images

Description: One problem in similarity-based object retrieval (SBOR) is how to define and estimate the similarity between two objects. In this paper we present a shape similarity measure based on thin-plate splines, and compare its performance with several other measures used in SBOR. We evaluate the methods on both artificial and real images.
Date: October 16, 2003
Creator: Fodor, I K
Item Type: Refine your search to only Article
open access

Chemical Sensing Using Infrared Cavity Enhanced Spectroscopy: Short Wave Infrared Cavity Ring Down Spectroscopy (SWIR CRDS) Sensor

Description: The principal goal of Pacific Northwest National Laboratory's (PNNL's) Remote Spectroscopy Project is to explore and develop the science and technology behind point and stand off infrared (IR) spectroscopic chemical sensors that are needed for detecting weapons proliferation activity and countering terrorism. Missions addressed include detecting chemical, biological, and nuclear weapons and their production; counter terrorism measures that involve screening luggage, personnel, and shipping cont… more
Date: October 1, 2003
Creator: Williams, Richard M.; Harper, Warren W.; Aker, Pam M.; Thompson, Jason S. & Stewart, Timothy L.
Item Type: Refine your search to only Report
open access

Innovative Approach to Establish Root Causes for Cracking in Aggressive Reactor Environments

Description: The research focuses on the high-resolution characterization of degradation microstructures and microchemistries in specimens tested under controlled conditions for the environment and for the material where in-service complexities can be minimized. Thermodynamic and kinetic modeling of crack-tip processes is employed to analyze corrosion-induced structures and gain insights into degradation mechanisms. Novel mechanistic ''fingerprinting'' of crack-tip structures is used to isolate causes of en… more
Date: October 31, 2003
Creator: Bruemmer, Stephen M.; Thomas, Larry E.; Vetrano, John S. & Simonen, Edward P.
Item Type: Refine your search to only Report
open access

Stochastic Kinetic Monte Carlo algorithms for long-range Hamiltonians

Description: We present a higher order kinetic Monte Carlo methodology suitable to model the evolution of systems in which the transition rates are non- trivial to calculate or in which Monte Carlo moves are likely to be non- productive flicker events. The second order residence time algorithm first introduced by Athenes et al.[1] is rederived from the n-fold way algorithm of Bortz et al.[2] as a fully stochastic algorithm. The second order algorithm can be dynamically called when necessary to eliminate unp… more
Date: October 13, 2003
Creator: Mason, D R; Rudd, R E & Sutton, A P
Item Type: Refine your search to only Article
open access

Coherent Communications, Imaging and Targeting

Description: Laboratory and field demonstration results obtained as part of the DARPA-sponsored Coherent Communications, Imaging and Targeting (CCIT) program are reviewed. The CCIT concept uses a Phase Conjugation Engine based on a quadrature receiver array, a hologram processor and a spatial light modulator (SLM) for high-speed, digital beam control. Progress on the enabling MEMS SLM, being developed by a consortium consisting of LLNL, academic institutions and small businesses, is presented.
Date: October 3, 2003
Creator: Stappaerts, E.; Baker, K.; Gavel, D.; Wilks, S.; Olivier, S.; Brase, J. et al.
Item Type: Refine your search to only Article
open access

The Factory Approach to Creating TSTT Meshes

Description: The factory approach (a.k.a. virtual constructor) hides the details of the class implementing the TSTT from TSTT users. In version 0.5 of TSTT.sidl, the client hard codes the name of the implementing class into their code. The client is forced to choose from the small set of possible concrete classes defined in TSTT.sidl. This approach makes it impossible to support multiple implementations of the TSTT in a single process because each implementation has to implement the same class. The factory … more
Date: October 21, 2003
Creator: Epperly, T
Item Type: Refine your search to only Report
open access

Evaluation of the Relative Importance of Parameters Influencing Perforation Cleanup

Description: Completion of cased and cemented wells by shaped-charge perforation results in damage to the formation, which can significantly reduce well productivity. Typically, underbalanced conditions are imposed during perforation in an effort to remove damaged rock and shaped-charge debris from the perforation tunnel. Immediately after the shaped-charge jet penetrates the formation, there is a transient surge of fluid from the formation through the perforation and into the well bore. Experimental eviden… more
Date: October 22, 2003
Creator: Detwiler, R L; Morris, J P; Karacan, C O; Halleck, P M & Hardesty, J
Item Type: Refine your search to only Article
open access

FY'03 OMEGA Summary for LLE Annual Report

Description: Lawrence Livermore National Laboratory (LLNL) continued, in FY03, to be a large user of Omega, using 390 experimental shots. These are roughly broken into 2 groups: those in support of the inertial confinement fusion (ICF) program; and those in support of high energy density sciences (HEDS), which includes materials, equation of state, and physics experiments.
Date: October 24, 2003
Creator: Turner, R E
Item Type: Refine your search to only Report
open access

A Fusion Chamber for the 2002 Robust Point Design

Description: A top-level overview of the mechanical design for the 2002 Robust Point Design (RPD-2002) fusion chamber is introduced. It is based on the HYLIFE-II design and includes modifications to the liquid pocket configuration and first structural wall (FSW), facilitates periodic maintenance or replacement of internal components, and is compliant with all other RPD-2002 parameters. This work has been carried out by constructing a parametric computer model capable of being updated as future changes becom… more
Date: October 1, 2003
Creator: Abbott, R P
Item Type: Refine your search to only Article
open access

Vehicle Buyer's Guide for Fleets: Clean Cities Tools and Resources (Fact Sheet)

Description: This fact sheet describes the Clean Cities Vehicle Buyer's Guide for Fleets. The Guide educates fleet managers and policymakers about alternative fuels and vehicles, helps managers learn if their fleets are affected by government regulations, and provides comprehensive information about currently available light- and heavy-duty AFVs.
Date: October 1, 2003
Item Type: Refine your search to only Text
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