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1-10 Mbar Laser-Driven Shocks Using the Janus Laser Facility (open access)

1-10 Mbar Laser-Driven Shocks Using the Janus Laser Facility

We report preliminary results using the Lawrence Livermore National Laboratory (LLNL) Janus laser facility to generate high pressure laser-driven shocks in the 1-10 Mbar regime. These experiments address various issues, including shock steadiness, planarity, uniformity and low target preheat, important for making precision EOS measurements on a small (E < 250 J) laser facility. A brief description of the experimental techniques, target design and measurements will be given.
Date: August 10, 2001
Creator: Dunn, J.; Price, D. F.; Moon, S. J.; Cauble, R. C.; Springer, P. T. & Ng, A.
System: The UNT Digital Library
Activation of theMercury Laser System: A Diode-Pumped Solid-State Laser Driver for Inertial Fusion (open access)

Activation of theMercury Laser System: A Diode-Pumped Solid-State Laser Driver for Inertial Fusion

Initial measurements are reported for the Mercury laser system, a scalable driver for rep-rated inertial fusion energy. The performance goals include 10% electrical efficiency at 10 Hz and 100 J with a 2-10 ns pulse length. We report on the first Yb:S-FAP crystals grown to sufficient size for fabricating full size (4 x 6 cm) amplifier slabs. The first of four 160 kW (peak power) diode arrays and pump delivery systems were completed and tested with the following results: 5.5% power droop over a 0.75 ms pulse, 3.95 nm spectral linewidth, far field divergence of 14.0 mrad and 149.5 mrad in the microlensed and unmicrolensed directions respectively, and 83% optical-to-optical transfer efficiency through the pump delivery system.
Date: September 10, 2001
Creator: Bayramian, A. J.; Beach, R. J.; Bibeau, C.; Ebbers, C. A.; Freitas, B. L.; Kanz, V. K. et al.
System: The UNT Digital Library
Advanced Three-Dimensional Deterministic and Monte Carlo Codes for Simulation of Real-Life Complex Nuclear Systems (open access)

Advanced Three-Dimensional Deterministic and Monte Carlo Codes for Simulation of Real-Life Complex Nuclear Systems

None
Date: January 10, 2001
Creator: Haghighat, A.
System: The UNT Digital Library
Aggregation and metal ion extraction properties of novel, silicon-substituted alkylenediphosphonic acids. (open access)

Aggregation and metal ion extraction properties of novel, silicon-substituted alkylenediphosphonic acids.

In conjunction with efforts to develop novel actinide extractants exhibiting solubility in supercritical carbon dioxide, the effect of adding silicon-based functionalities to diphosphonic acids has been investigated. Specifically, a series of silyl-substituted diphosphonic acids has been prepared and characterized, and their aggregation and metal ion extraction properties compared with alkyl-substituted diphosphonic acids, reagents previously demonstrated to be effective extractants of actinides from acidic aqueous media into various organic solvents. In addition, the influence of the number of methylene groups bridging the phosphorus atoms of the diphosphonic acids on their extraction behavior has been investigated. Variations in the extraction behavior of the compounds arising from differences in the number of bridging methylene groups have been shown to be attributable to a combination of factors, in particular, the aggregation state of the ligand, the size of the chelate rings formed upon complexation, the basicity of the phosphoryl group and the relative acidities of the ligands.
Date: May 10, 2001
Creator: McAlister, D. R.; Dietz, M. L.; Chiarizia, R. & Herlinger, A. W.
System: The UNT Digital Library
ALS superbend magnet performance (open access)

ALS superbend magnet performance

The Lawrence Berkeley National Laboratory has been engaged in the design, construction and testing of four superconducting dipoles (Superbends) that are installed in three arcs of the Advanced Light Source (ALS), with the fourth magnet as a spare. This represents a major upgrade to the ALS providing an enhanced flux and brightness at photon energies above 10 keV. In preparation for installation, an extensive set of tests and measurements have been conducted to characterize the magnetic and cryogenic performance of the Superbends and to fiducialize them for accurate placement in the ALS storage ring. The magnets are currently installed, and the storage ring is undergoing final commissioning. This paper will present the results of magnetic and cryogenic testing.
Date: December 10, 2001
Creator: Marks, Steve; Zbasnik, John; Byrne, Warren; Calais, Dennis; Chin, Michael; DeMarco, Richard et al.
System: The UNT Digital Library
At-wavelength characterization of the extreme ultraviolet Engineering Test Stand Set-2 optic (open access)

At-wavelength characterization of the extreme ultraviolet Engineering Test Stand Set-2 optic

At-wavelength interferometric characterization of a new 4x-reduction lithographic-quality extreme ultraviolet (EUV) optical system is described. This state-of-the-art projection optic was fabricated for installation in the EUV lithography Engineering Test Stand (ETS) and is referred to as the ETS Set-2 optic. EUV characterization of the Set-2 optic is performed using the EUV phase-shifting point diffraction interferometer (PS/PDI) installed on an undulator beamline at Lawrence Berkeley National Laboratory's Advanced Light Source. This is the same interferometer previously used for the at-wavelength characterization and alignment of the ETS Set-1 optic. In addition to the PS/PDI-based full-field wavefront characterization, we also present wavefront measurements performed with lateral shearing interferometry, the chromatic dependence of the wavefront error, and the system-level pupil-dependent spectral-bandpass characteristics of the optic; the latter two properties are only measurable using at-wavelength interferometry.
Date: June 10, 2001
Creator: Naulleau, Patrick; Goldberg, Kenneth A.; Anderson, Erik H.; Batson, Phillip; Denham, Paul E.; Jackson, Keith H. et al.
System: The UNT Digital Library
ATM phosphorylates histone H2AX in response to DNA double-strand breaks (open access)

ATM phosphorylates histone H2AX in response to DNA double-strand breaks

None
Date: October 10, 2001
Creator: Burma, Sandeep; Chen, Benjamin P.; Murphy, Michael; Kurimasa, Akihiro & Chen, David J.
System: The UNT Digital Library
Atomic Level Characterization of Neutron Irradiated Pressure Vessel Steels (open access)

Atomic Level Characterization of Neutron Irradiated Pressure Vessel Steels

None
Date: January 10, 2001
Creator: Miller, M. K.
System: The UNT Digital Library
Benchmarking Residential Energy Use (open access)

Benchmarking Residential Energy Use

Interest in rating the real-life energy performance of buildings has increased in recent years, and real-life efficiency performance rating of buildings is important for any sustainable energy future. Work on rating commercial buildings energy performance has shown important promise for helping increase commercial sector energy efficiency. Since residential buildings account for over half of all buildings-related energy use in the US, methods to rate residential energy performance should also be important. Initial work on the 1993 Residential Energy Consumption Survey has been conducted to examine issues and approaches for residential energy performance rating tools, and some of these issues and approaches are presented in this paper. A method is presented for developing an energy performance rating or ranking procedure for residences in the US based on regression analyses covering the entire residential sector, which covers mobile homes to apartments in large buildings. The same approach could be applied to subsets, such as single family detached houses. Significant additional work on the best methods to use to rate residential energy performance, causes of high and low performance, and other applications of these methods is needed.
Date: January 10, 2001
Creator: MacDonald, J. M.
System: The UNT Digital Library
Bioenergy Status and Expansion in the United States (open access)

Bioenergy Status and Expansion in the United States

None
Date: January 10, 2001
Creator: Wright, L.L.
System: The UNT Digital Library
Biomass Feedstock Research and Development for Multiple Products in the United States (open access)

Biomass Feedstock Research and Development for Multiple Products in the United States

A recent presidential Executive Order to triple current levels of bioenergy and biobased production by 2010 has increased interest in determining whether sufficient biomass resources will be economically available to support the goal. The US has a well-structured program of research and development which is focusing on increasing potential energy crop and crop residue availability under economically and environmentally sustainable conditions. Genetic improvement programs are ongoing in three U. S. locations for hybrid poplar and cottonwood, in one location for willow, and in four locations for switchgrass. Variety testing and cropping systems development is being conducted at wider variety of sites for all three crops. Molecular genetics is providing important information and tools for identifying and controlling desired traits. The program is also expanding to address supply logistics issues for both energy crop and residues. Equilibrium model analysis performed jointly with the US Department of Agriculture suggests that at farmgate prices of about $33 dt and $44 dt, between 7 and 17 million ha of land could convert to energy crop production without negatively affecting food supplies. Large amounts of crop residue also become profitable for farmers to collect at similar prices. This potential for supporting significant bioenergy and biobased …
Date: January 10, 2001
Creator: Wright, L.L.
System: The UNT Digital Library
Biomonitoring for Environmental Compliance at Select DOE Facilities: Fifteen Years of the Biomonitoring and Abatement Program (open access)

Biomonitoring for Environmental Compliance at Select DOE Facilities: Fifteen Years of the Biomonitoring and Abatement Program

None
Date: January 10, 2001
Creator: Peterson, M. J.
System: The UNT Digital Library
Breakup and Recombination of Identical Bosons: He Dimer-Monomer Collisions (open access)

Breakup and Recombination of Identical Bosons: He Dimer-Monomer Collisions

None
Date: January 10, 2001
Creator: Macek, J.H.
System: The UNT Digital Library
Calculational Benchmark Problems for VVER-1000 Mixed Oxide Fuel Cycle (open access)

Calculational Benchmark Problems for VVER-1000 Mixed Oxide Fuel Cycle

None
Date: January 10, 2001
Creator: Emmett, M.B.
System: The UNT Digital Library
Cell motility and metastatic potential studies based on quantum dot imaging of phagokinetic tracks (open access)

Cell motility and metastatic potential studies based on quantum dot imaging of phagokinetic tracks

None
Date: December 10, 2001
Creator: Parak, Wolfgang J.; Boudreau, Rosanne; Le Gros, Mark A.; Gerion, Daniele; Zanchet, Daniela; Micheel, Christine M. et al.
System: The UNT Digital Library
Chemical genealogy of an atmospheric chemist : James N. Pitts, Jr., a case study. (open access)

Chemical genealogy of an atmospheric chemist : James N. Pitts, Jr., a case study.

None
Date: October 10, 2001
Creator: Gaffney, J. S. & Marley, N. A.
System: The UNT Digital Library
The computational crystallography toolbox: Crystallographic algorithms in a modern software framework (open access)

The computational crystallography toolbox: Crystallographic algorithms in a modern software framework

None
Date: October 10, 2001
Creator: Grosse-Kunstleve, Ralf W.; Sauter, Nicholas K.; Moriarty, Nigel W. & Adams, Paul D.
System: The UNT Digital Library
Conjugation of DNA to Silanized Colloidal Semiconductor Nanocrystalline Quantum Dots (open access)

Conjugation of DNA to Silanized Colloidal Semiconductor Nanocrystalline Quantum Dots

Water-soluble, highly fluorescent, silanized semiconductor nanocrystals with different surface charges were synthesized. To covalently attach the nanocrystals to biological macromolecules with a variety of mild coupling chemistries, the outermost siloxane shells were derivatized with thiol, amino, or carboxyl functional groups. Single- or double-stranded DNA was coupled to the nanocrystal surfaces by using commercially available bifunctional cross-linker. Conjugation had little effect on the optical properties of the nanocrystals, and the resulting conjugates were more stable than previously reported systems. By using the strategies developed in this study, most biomolecules can be covalently coupled to semiconductor nanocrystals. These nanocrystal-DNA conjugates promise to be a versatile tool for fluorescence imaging and probing of biological systems.
Date: September 10, 2001
Creator: Parak, Wolfgang J.; Gerion, Daniele; Zanchet, Daniela; Waerz, Anke S.; Micheel, Christine; Williams, Shara C. et al.
System: The UNT Digital Library
Consumer life-cycle cost impacts of energy-efficiency standards for residential-type central air conditioners and heat pumps (open access)

Consumer life-cycle cost impacts of energy-efficiency standards for residential-type central air conditioners and heat pumps

In support of the federal government's efforts to raise the minimum energy-efficiency standards for residential-type central air conditioners and heat pumps, a consumer life-cycle cost (LCC) analysis was conducted to demonstrate the economic impacts on individual consumers from revisions to the standards. LCC is the consumer's cost of purchasing and installing an air conditioner or heat pump and operating the unit over its lifetime. The LCC analysis is conducted on a nationally representative sample of air conditioner and heat pump consumers resulting in a distribution of LCC impacts showing the percentage of consumers that are either benefiting or being burdened by increased standards. Relative to the existing minimum efficiency standard of 10 SEER, the results show that a majority of split system air conditioner and heat pump consumers will either benefit or be insignificantly impacted by increased efficiency standards of up to 13 SEER.
Date: October 10, 2001
Creator: Rosenquist, Gregory; Chan, Peter; Lekov, Alex; McMahon, James & Van Buskirk, Robert
System: The UNT Digital Library
Cross-Flow Ultrafiltration with a Shear-Thinning Organic Based Slurry (open access)

Cross-Flow Ultrafiltration with a Shear-Thinning Organic Based Slurry

The Department of Energy is sponsoring the River Protection Project, which includes the design of a facility to stabilize liquid radioactive waste that is stored at the Hanford Site. Because of its experience with radioactive waste stabilization, the Savannah River Technology Center (SRTC) of the Westinghouse Savannah River Company was contracted to develop and test parts of the waste treatment process. One part of the process is the separation of highly radioactive solids from the liquid wastes by precipitation and cross-flow filtration. A cross-flow filter was tested with simulated wastes made to represent typical waste chemical and physical characteristics. This paper discusses the results of cross-flow filter operation in a pilot-scale facility that was designed, built, and run by the Experimental Thermal Fluids SRTC.
Date: January 10, 2001
Creator: Duignan, M.R.
System: The UNT Digital Library
Current Status of the Oak Ridge Monte Carlo Codes: MORSE/SAS4 and KENO (open access)

Current Status of the Oak Ridge Monte Carlo Codes: MORSE/SAS4 and KENO

None
Date: January 10, 2001
Creator: Emmett, M.B.
System: The UNT Digital Library
Defining interactions between DNA-PK and ligase IV/XRCC4 (open access)

Defining interactions between DNA-PK and ligase IV/XRCC4

Non-homologous end joining (NHEJ) is a major pathway for the repair of DNA double-strand breaks in mammalian cells. DNA-dependent protein kinase (DNA-PK), ligase IV, and XRCC4 are all critical components of the NHEJ repair pathway. DNA-PK is composed of a heterodimeric DNA-binding component, Ku, and a large catalytic subunit, DNA-PKcs. Ligase IV and XRCC4 associate to form a multimeric complex that is also essential for NHEJ. DNA-PK and ligase IV/XRCC4 interact at DNA termini which results in stimulated ligase activity. Here we define interactions between the components of these two essential complexes, DNA-PK and ligase IV/XRCC4. We find that ligase IV/XRCC4 associates with DNA-PK in a DNA-independent manner. The specific protein-protein interactions that mediate the interaction between these two complexes are further identified. Direct physical interactions between ligase IV and Ku as well as between XRCC4 and DNA-PKcs are shown. No direct interactions are observed between ligase IV and DNA-PKcs or between XRCC4 and Ku. Our data defines the specific protein pairs involved in the association of DNA-PK and ligase IV/XRCC4, and suggests a molecular mechanism for coordinating the assembly of the DNA repair complex at DNA breaks.
Date: April 10, 2001
Creator: Hsu, Hsin-Ling; Yannone, Steven M. & Chen, David J.
System: The UNT Digital Library
Design Parameters for Graphite-Reflected Graphite-Foam-U Cores with Zero Burnup Reactivity Swing (open access)

Design Parameters for Graphite-Reflected Graphite-Foam-U Cores with Zero Burnup Reactivity Swing

None
Date: January 10, 2001
Creator: Difilippo, F. C.
System: The UNT Digital Library