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TECHNOLOGY NEEDS AND STATUS ON CLOSURE OF DOE RADIOACTIVE WASTE TANK ANCILLARY SYSTEMS

Description: This paper summarizes the current state of art of sampling, characterizing, retrieving, transferring and treating the incidental waste and stabilizing the void space in tank ancillary systems and the needs involved with closure of these systems. The overall effort for closing tank and ancillary systems is very large and is in the initial stages of being addressed in a systematic manner. It was recognized in doing this effort, that gaps in both technology and material application for characteriz… more
Date: January 21, 2009
Creator: Burns, H; Sharon Marra, S & Christine Langton, C
Partner: UNT Libraries Government Documents Department
open access

The Mercury Laser Advances Laser Technology for Power Generation

Description: The National Ignition Facility (NIF) at Lawrence Livermore Laboratory is on target to demonstrate 'breakeven' - creating as much fusion-energy output as laser-energy input. NIF will compress a tiny sphere of hydrogen isotopes with 1.8 MJ of laser light in a 20-ns pulse, packing the isotopes so tightly that they fuse together, producing helium nuclei and releasing energy in the form of energetic particles. The achievement of breakeven will culminate an enormous effort by thousands of scientists … more
Date: January 21, 2009
Creator: Ebbers, C A; Caird, J & Moses, E
Partner: UNT Libraries Government Documents Department
open access

Lessons Learned in Risk Management on NCSX

Description: The National Compact Stellarator Experiment (NCSX) was designed to test physics principles of an innovative stellarator design developed by the Princeton Plasma Physics Laboratory and Oak Ridge National Laboratory. Construction of some of the major components and sub-assemblies was completed, but the estimated cost and schedule for completing the project grew as the technical requirements and risks became better understood, leading to its cancellation in 2008. The project's risks stemmed from i… more
Date: July 21, 2009
Creator: G.H. Neilson, C.O. Gruber, J.H. Harris, D.J. Rej, R.T. Simmons, and R.L. Strykowsky
Partner: UNT Libraries Government Documents Department
open access

Versatile P(acman) BAC Libraries for Transgenesis Studies in Drosophila melanogaster

Description: We constructed Drosophila melanogaster BAC libraries with 21-kb and 83-kb inserts in the P(acman) system. Clones representing 12-fold coverage and encompassing more than 95percent of annotated genes were mapped onto the reference genome. These clones can be integrated into predetermined attP sites in the genome using Phi C31 integrase to rescue mutations. They can be modified through recombineering, for example to incorporate protein tags and assess expression patterns.
Date: April 21, 2009
Creator: Venken, Koen J.T.; Carlson, Joseph W.; Schulze, Karen L.; Pan, Hongling; He, Yuchun; Spokony, Rebecca et al.
Partner: UNT Libraries Government Documents Department
open access

Spinel ferrite nanocrystals embedded inside ZnO: magnetic, electronic andmagneto-transport properties

Description: In this paper we show that spinel ferrite nanocrystals (NiFe{sub 2}O{sub 4}, and CoFe{sub 2}O{sub 4}) can be texturally embedded inside a ZnO matrix by ion implantation and post-annealing. The two kinds of ferrites show different magnetic properties, e.g. coercivity and magnetization. Anomalous Hall effect and positive magnetoresistance have been observed. Our study suggests a ferrimagnet/semiconductor hybrid system for potential applications in magneto-electronics. This hybrid system can be tu… more
Date: August 21, 2009
Creator: Zhou, Shengqiang; Potzger, K.; Xu, Qingyu; Kuepper, K.; Talut, G.; Marko, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Recent Fast Wave Coupling and Heating Studies on NSTX, with Possible Implications for ITER

Description: The goal of the high harmonic fast wave (HHFW) research on NSTX is to maximize the coupling of RF power to the core of the plasma by minimizing the coupling of RF power to edge loss processes. HHFW core plasma heating efficiency in helium and deuterium L-mode discharges is found to improve markedly on NSTX when the density 2 cm in front of the antenna is reduced below that for the onset of perpendicular wave propagation (nonset ∝ B*k|| 2/ω). In NSTX, the observed RF power losses in the plasma e… more
Date: July 21, 2009
Creator: J.C. Hosea, R.E. Bell, E. Feibush, R.W. Harvey, E.F. Jaeger, B.P LeBlanc, R. Maingi, C.K. Phillips, L. Roquemore, P.M. Ryan, G. Taylor, K. Tritz, E.J. Valeo, J. Wilgen, J.R. Wilson, and the NSTX Team
Partner: UNT Libraries Government Documents Department
open access

Conceptual Engineering Method for Attenuating He Ion Interactions on First Wall Components in the Fusion Test Facility (FTF) Employing a Low-Pressure Noble Gas

Description: It has been shown that post detonation energetic helium ions can drastically reduce the useful life of the (dry) first wall of an IFE reactor due to the accumulation of implanted helium. For the purpose of attenuating energetic helium ions from interacting with first wall components in the Fusion Test Facility (FTF) target chamber, several concepts have been advanced. These include magnetic intervention (MI), deployment of a dynamically moving first wall, use of a sacrificial shroud, designing … more
Date: September 21, 2009
Creator: C.A.Gentile, W.R.Blanchard, T.Kozub, C.Priniski, I.Zatz, S.Obenschain
Partner: UNT Libraries Government Documents Department
open access

THE IMPACT OF DISSOLVED SALTS ON PASTES CONTAINING FLY ASH, CEMENT AND SLAG

Description: The degree of hydration of a mixture of cementitious materials (Class F fly ash, blast furnace slag and portland cement) in highly concentrated alkaline salt solutions is enhanced by the addition of aluminate to the salt solution. This increase in the degree of hydration, as monitored with isothermal calorimetry, leads to higher values of dynamic Young's modulus and compressive strength and lower values of total porosity. This enhancement in performance properties of these cementitious waste fo… more
Date: September 21, 2009
Creator: Harbour, J.; Edwards, T. & Williams, V.
Partner: UNT Libraries Government Documents Department
open access

Protein Kinase CK2 Regulates Cytoskeletal Reorganization during Ionizing Radiation-Induced Senescence of Human Mesenchymal Stem Cells

Description: Human mesenchymal stem cells (hMSC) are critical for tissue regeneration. How hMSC respond to genotoxic stresses and potentially contribute to aging and cancer remain underexplored. We demonstrated that ionizing radiation induced cellular senescence of hMSC over a period of 10 days, showing a critical transition between day 3 and day 6. This was confirmed by senescence-associated beta-galactosidase (SA-{beta}-gal) staining, protein expression profiles of key cell cycle regulators (retinoblastom… more
Date: August 21, 2009
Creator: Wang, Daojing & Jang, Deok-Jin
Partner: UNT Libraries Government Documents Department
open access

New Accessory for Cleaning the Inside of the Machine Tool Cavity

Description: The best way to extend the life of a metalworking fluid (MWF) is to make sure the machine tool and MWF delivery system are properly cleaned at least once per year. The dilemma the MWF manager is faced with is: How does one clean the machine tool and the MWF system on a large machine tool with an enclosure in a timely manner without impacting production schedules? Remember the walls and roof of the machine enclosure are coated with a film of dried contaminated MWF that must also be removed. If n… more
Date: April 21, 2009
Creator: Lazarus, Lloyd
Partner: UNT Libraries Government Documents Department
open access

Europium-doped barium bromide iodide

Description: Single crystals of Ba0.96Eu0.04BrI (barium europium bromide iodide) were grown by the Bridgman technique. The title compound adopts the ordered PbCl2 structure [Braekken (1932). Z. Kristallogr. 83, 222-282]. All atoms occupy the fourfold special positions (4c, site symmetry m) of the space group Pnma with a statistical distribution of Ba and Eu. They lie on the mirror planes, perpendicular to the b axis at y = +-0.25. Each cation is coordinated by nine anions in a tricapped trigonal prismatic a… more
Date: October 21, 2009
Creator: Gundiah, Gautam; Hanrahan, Stephen M.; Hollander, Fredrick J. & Bourret-Courchesne, Edith D.
Partner: UNT Libraries Government Documents Department
open access

Development of Li+ alumino-silicate ion source

Description: To uniformly heat targets to electron-volt temperatures for the study of warm dense matter, one strategy is to deposit most of the ion energy at the peak of energy loss (dE/dx) with a low (E< 5 MeV) kinetic energy beam and a thin target[1]. Lower mass ions have a peak dE/dx at a lower kinetic energy. To this end, a small lithium (Li+) alumino-silicate source has been fabricated, and its emission limit has been measured. These surface ionization sources are heated to 1000-1150 C where they pr… more
Date: April 21, 2009
Creator: Roy, P.K.; Seidl, P.A.; Waldron, W.; Greenway, W.; Lidia, S.; Anders, A. et al.
Partner: UNT Libraries Government Documents Department
open access

Invariability of Central Metabolic Flux Distribution in Shewanella oneidensis MR-1 Under Environmental or Genetic Perturbations

Description: An environmentally important bacterium with versatile respiration, Shewanella oneidensis MR-1, displayed significantly different growth rates under three culture conditions: minimal medium (doubling time {approx} 3 hrs), salt stressed minimal medium (doubling time {approx} 6 hrs), and minimal medium with amino acid supplementation (doubling time {approx}1.5 hrs). {sup 13}C-based metabolic flux analysis indicated that fluxes of central metabolic reactions remained relatively constant under the t… more
Date: April 21, 2009
Creator: Tang, Yinjie; Martin, Hector Garcia; Deutschbauer, Adam; Feng, Xueyang; Huang, Rick; Llora, Xavier et al.
Partner: UNT Libraries Government Documents Department
open access

Recent Fast Wave Coupling and Heating Studies on NSTX, with Possible Implications for ITER

Description: The goal of the high harmonic fast wave (HHFW) research on NSTX is to maximize the coupling of RF power to the core of the plasma by minimizing the coupling of RF power to edge loss processes. HHFW core plasma heating efficiency in helium and deuterium L-mode discharges is found to improve markedly on NSTX when the density 2 cm in front of the antenna is reduced below that for the onset of perpendicular wave propagation (nonset ∝ B*k|| 2/ω). In NSTX, the observed RF power losses in the plasma e… more
Date: July 21, 2009
Creator: J.C. Hosea, R.E. Bell, E. Feibush, R.W. Harvey, E.F. Jaeger, B.P LeBlanc, R. Maingi, C.K. Phillips, L. Roquemore, P.M. Ryan, G. Taylor, K. Tritz, E.J. Valeo, J. Wilgen, J.R. Wilson, and the NSTX Team
Partner: UNT Libraries Government Documents Department
open access

High Power, High Voltage FETs in Linear Applications: A User's Perspective

Description: The specifications of the current crop of highpower, high-voltage field-effect transistors (FETs) can lure a designer into employing them in high-voltage DC equipment. Devices with extremely low on-resistance and very high power ratings are available from several manufacturers. However, our experience shows that high-voltage, linear operation of these devices at near-continuous duty can present difficult reliability challenges at stress levels well-below their published specifications. This pap… more
Date: September 21, 2009
Creator: Greenough, N.; Fredd, E. & DePasquale, S.
Partner: UNT Libraries Government Documents Department
open access

Highly Selective Synthesis of Catalytically Active Monodisperse Rhodium Nanocubes

Description: Synthesis of monodisperse and shape-controlled colloidal inorganic nanocrystals (NCs) is of increasing scientific interest and technological significance. Recently, shape control of Pt, Pd, Ag, Au, and Rh NCs has been obtained by tuning growth kinetics in various solution-phase approaches, including modified polyol methods, seeded growth by polyol reduction, thermolysis of organometallics, and micelle techniques. Control of reduction kinetics of the noble metal precursors and regulation of the … more
Date: February 21, 2009
Creator: Zhang, Y.; Grass, M. E.; Kuhn, J. N.; Tao, F.; Habas, S. E.; Huang, W. et al.
Partner: UNT Libraries Government Documents Department
open access

Investigation of a Gas Jet-Produced Hollow Plasma Wakefield Accelerator

Description: The effect of ion motion and the need for practical positron propagation in a plasma wakefield accelerator (PWFA) have incited interest in hollow plasma channels. These channels are typically assumed to be cylindrically symmetric; however, a different geometry might be easier to achieve. The introduction of an obstruction into the outlet of a high Mach number gas jet can produce two parallel slabs of gas separated by a density depression. Here, there is a detailed simulation study of the densit… more
Date: May 21, 2009
Creator: Kirby, N; Blumenfeld, I.; Hogan, M. J.; Siemann, R. H.; Walz, D. R.; Davidson, A. W. et al.
Partner: UNT Libraries Government Documents Department
open access

EFFECTS OF GAMMA RADIATION ON ELECTROCHEMICAL PROPERTIES OF IONIC LIQUIDS

Description: The electrochemical properties of ionic liquids (ILs) make them attractive for possible replacement of inorganic salts in high temperature molten salt electrochemical processing of nuclear fuel. To be a feasible replacement solvent, ILs need to be stable in moderate and high doses of radiation without adverse chemical and physical effects. Here, we exposed seven different ILs to a 1.2 MGy dose of gamma radiation to investigate their physical and chemical properties as they related to radiologic… more
Date: April 21, 2009
Creator: Visser, A; Nicholas Bridges, N; Thad Adams, T; John Mickalonis, J & Mark02 Williamson, M
Partner: UNT Libraries Government Documents Department
open access

Major Successes of Theory-and-Experiment-Combined Studies in Surface Chemistry and Heterogeneous Catalysis.

Description: Experimental discoveries followed by theoretical interpretations that pave the way of further advances by experimentalists is a developing pattern in modern surface chemistry and catalysis. The revolution of modern surface science started with the development of surface-sensitive techniques such as LEED, XPS, AES, ISS and SIMS, in which the close collaboration between experimentalists and theorists led to the quantitative determination of surface structure and composition. The experimental disc… more
Date: November 21, 2009
Creator: Somorjai, Gabor A. & Li, Yimin
Partner: UNT Libraries Government Documents Department
open access

The Strength of Single Crystal Copper under Uniaxial Shock Compression at Mbar pressures

Description: In situ x-ray diffraction has been used to measure the shear strain (and thus strength) of single crystal copper shocked to Mbar pressures along the [001] and [111] axes. These direct shear strain measurements indicate shear strengths at these ultra-high strain rates (of order 10{sup 9} s{sup -1}) of a few GPa, which are both broadly in agreement with the extrapolation of lower strain-rate data and with non-equilibrium molecular dynamics simulations.
Date: May 21, 2009
Creator: Murphy, W; Higginbotham, A; Kimminau, G; Barbrel, B; Bringa, E; Hawreliak, J et al.
Partner: UNT Libraries Government Documents Department
open access

Over Voltage in a Multi-sectioned Solenoid during a Quenching

Description: Accurate analysis of over voltage in the superconducting solenoid during a quench is one of the bases for quench protection system design. Classical quench simulation methods can only give rough estimation of the over voltage within a magnet coil. In this paper, for multi-sectioned superconducting solenoid, based on the classical assumption of ellipsoidal normal zone, three-dimension al temperature results are mapped to the one-dimension of the wire, the temperature distribution along the wire … more
Date: June 21, 2009
Creator: Guo, Xinglong; Wang, Li; Pan, Heng; Wu, Hong; Liu, Xiaokun; Chen, Anbin et al.
Partner: UNT Libraries Government Documents Department
open access

Nuclear Recoil Cross Sections from Time-dependent Studies of Two-Photon Double Ionization of Helium

Description: We examine the sensitivity of nuclear recoil cross sections produced by two-photon double ionization of helium to the underlying triple differential cross sections (TDCS) used in their computation. We show that this sensitivity is greatest in the energy region just below the threshold for sequential double ionization. Accurate TDCS, extracted from non-perturbative solutions of the time-dependent Schroedinger equation, are used here in new computations of the nuclear recoil cross section.
Date: December 21, 2009
Creator: Horner, Daniel A.; Rescigno, Thomas N. & McCurdy, C. William
Partner: UNT Libraries Government Documents Department
open access

Spectroscopic signatures of proton transfer dynamics in the water dimer cation

Description: Using full dimensional EOM-IP-CCSD/aug-cc-pVTZ potential energy surfaces, the photoelectron spectrum, vibrational structure, and ionization dynamics of the water dimer radical cation, (H2O)+2, were computed. We also report an experimental photoelectron spectrum which is derived from photoionization efficiency measurements and compares favorably with the theoretical spectrum. The vibrational structure is also compared with the recent experimental work of Gardenier et al. [J. Phys. Chem. A 113, 4… more
Date: December 21, 2009
Creator: Kamarchik, Eugene; Kostko, Oleg; Bowman, Joel M.; Ahmed, Musahid & Krylov, Anna I.
Partner: UNT Libraries Government Documents Department
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