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Effect of Organic Acid Additions on the General and Localized Corrosion Susceptibility of Alloy 22 in Chloride Solutions

Description: Electrochemical studies such as cyclic potentiodynamic polarization (CPP) and electrochemical impedance spectroscopy (EIS) were performed to determine the corrosion behavior of Alloy 22 (N06022) in 1M NaCl solutions at various pH values from acidic to neutral at 90 C. All the tested material was wrought Mill Annealed (MA). Tests were also performed in NaCl solutions containing weak organic acids such as oxalic, acetic, citric and picric. Results show that the corrosion rate of Alloy 22 was sign… more
Date: August 28, 2007
Creator: Carranza, R M; Giordano, C M; Rodr?guez, M A; Ilevbare, G O & Rebak, R B
Partner: UNT Libraries Government Documents Department
open access

Development of Wind-and-React Bi-2212 Accelerator MagnetTechnology

Description: We report on the progress in our R&D program, targetedto develop the technology for the application of Bi2Sr2CaCu2Ox (Bi-2212)in accelerator magnets. The program uses subscale coils, wound frominsulated cables, to study suitable materials, heat treatmenthomogeneity, stability, and effects ofmagnetic field and thermal andelectro-magnetic loads. We have addressed material and reaction relatedissues and report onthe fabrication, heat treatment, and analysis ofsubscale Bi-2212 coils. Such coils can… more
Date: August 28, 2007
Creator: Godeke, A.; Cheng, D.; Dietderich, D. R.; English, C. D.; Felice, H.; Hannaford, C. R. et al.
Partner: UNT Libraries Government Documents Department
open access

Three-body breakup in dissociative electron attachment to the water molecule

Description: We report the results of {\em ab initio} calculations on dissociative electron attachment (DEA) to water that demonstrate the importance of including three-body breakup in the dissociation dynamics. While three-body breakup is ubiquitous in the analogous process of dissociative recombination, its importance in low-energy dissociative electron attachment to a polyatomic target has not previously been quantified. Our calculations, along with our earlier studies of DEA into two-body channels, indi… more
Date: August 28, 2008
Creator: Haxton, Daniel J.; Rescigno, Thomas N. & McCurdy, C. William
Partner: UNT Libraries Government Documents Department
open access

Enhancement of T1 and T2 relaxation by paramagnetic silica-coated nanocrystals

Description: We present the first comprehensive investigation on water-soluble nanoparticles embedded into a paramagnetic shell and their properties as an MRI contrast agent. The nanoprobes are constructed with an inorganic core embedded into an ultra-thin silica shell covalently linked to chelated Gd{sup 3+} paramagnetic ions that act as an MRI contrast agent. The chelator contains the molecule DOTA and the inorganic core contains a fluorescent CdSe/ZnS qdots in Au nanoparticles. Optical properties of the … more
Date: August 28, 2006
Creator: Gerion, D; Herberg, J; Gjersing, E; Ramon, E; Maxwell, R; Gray, J W et al.
Partner: UNT Libraries Government Documents Department
open access

Metal-induced assembly of a semiconductor-island lattice: Getruncated pyramids on Au-patterned Si

Description: We report the two-dimensional alignment of semiconductor islands using rudimentary metal patterning to control nucleation and growth. In the Ge on Si system, a square array of sub-micron Au dots on the Si (001) surface induces the assembly of deposited Ge adatoms into an extensive island lattice. Remarkably, these highly ordered Ge islands form between the patterned Au dots and are characterized by a unique truncated pyramidal shape. A model based on patterned diffusion barriers explains the ob… more
Date: August 28, 2005
Creator: Robinson, J. T.; Liddle, J. A.; Minor, A.; Radmilovic, V.; Yi, D. O.; Greaney, P. A. et al.
Partner: UNT Libraries Government Documents Department
open access

Modeling cation diffusion in compacted water-saturatedNa-bentonite at low ionic strength

Description: Sodium bentonites are used as barrier materials for the isolation of landfills and are under consideration for a similar use in the subsurface storage of high-level radioactive waste. The performance of these barriers is determined in large part by molecular diffusion in the bentonite pore space. We tested two current models of cation diffusion in bentonite against experimental data on the relative apparent diffusion coefficients of two representative cations, sodium and strontium. On the 'macr… more
Date: August 28, 2007
Creator: Bourg, Ian C.; Sposito, Garrison & Bourg, Alain C.M.
Partner: UNT Libraries Government Documents Department
open access

The Resolution of Chiral, Tetrahedral M4L6 Metal-LigandHosts

Description: The supramolecular metal-ligand assemblies of M{sub 4}1{sub 6} stoichiometry are chiral (M = Ga{sup III}, Al{sup III}, In{sup III}, Fe{sup III}, Ti{sup IV}, or Ge{sup IV}, H{sub 4}1 = N,N'-bis(2,3-dihydroxybenzoyl)-1,5-diaminonaphthalene). The resolution process of {Delta}{Delta}{Delta}{Delta}- and {Lambda}{Lambda}{Lambda}{Lambda}-[M{sub 4}1{sub 6}]{sup 12-} by the chiral cation s-nicotinium (S-nic{sup +}) is described for the Ga{sup III}, Al{sup III}, and Fe{sup III} assemblies, and the resolu… more
Date: August 28, 2007
Creator: Davis, Anna V.; Fiedler, Dorothea; Ziegler, Marco; Terpin,Andreas & Raymond, Kenneth N.
Partner: UNT Libraries Government Documents Department
open access

Widespread Discordance of Gene Trees with Species Tree inDrosophila: Evidence for Incomplete Lineage Sorting

Description: The phylogenetic relationship of the now fully sequencedspecies Drosophila erecta and D. yakuba with respect to the D.melanogaster species complex has been a subject of controversy. All threepossible groupings of the species have been reported in the past, thoughrecent multi-gene studies suggest that D. erecta and D. yakuba are sisterspecies. Using the whole genomes of each of these species as well as thefour other fully sequenced species in the subgenus Sophophora, we set outto investigate the… more
Date: August 28, 2006
Creator: Pollard, Daniel A.; Iyer, Venky N.; Moses, Alan M. & Eisen,Michael B.
Partner: UNT Libraries Government Documents Department
open access

Preparing for Ignition Experiments on the National Ignition Facility

Description: The National Ignition Facility (NIF) is a 192-beam Nd-glass laser facility presently under construction at Lawrence Livermore National Laboratory (LLNL) for performing ignition experiments for inertial confinement fusion (ICF) and experiments studying high energy density (HED) science. NIF will produce 1.8 MJ, 500 TW of ultraviolet light ({lambda} = 351 nm) making it the world's largest and most powerful laser system. NIF will be the world's preeminent facility for the study of matter at extrem… more
Date: August 28, 2007
Creator: Moses, E & Meier, W
Partner: UNT Libraries Government Documents Department
open access

Application of High-performance Visual Analysis Methods to Laser Wakefield Particle Acceleration Data

Description: Our work combines and extends techniques from high-performance scientific data management and visualization to enable scientific researchers to gain insight from extremely large, complex, time-varying laser wakefield particle accelerator simulation data. We extend histogram-based parallel coordinates for use in visual information display as well as an interface for guiding and performing data mining operations, which are based upon multi-dimensional and temporal thresholding and data subsetting… more
Date: August 28, 2008
Creator: Rubel, Oliver; Prabhat, Mr.; Wu, Kesheng; Childs, Hank; Meredith, Jeremy; Geddes, Cameron G.R. et al.
Partner: UNT Libraries Government Documents Department
open access

Characterization of Recompressed Spall in Copper Gas Gun Targets

Description: Complementary experiments and simulations are conducted to characterize the microstructure and mechanisms involved in recompression of spalled ductile metals. Soft capture experiments performed on copper targets in a gas gun include a dense secondary plate spaced behind the customary flyer to recompress the voids in the wake of the spall induced by the flyer. Control experiments are run without the secondary plate to obtain spall damage without recompression. The simulations feature explicit re… more
Date: August 28, 2006
Creator: Becker, R.; Cazamias, J. & LeBlanc, M.
Partner: UNT Libraries Government Documents Department
open access

Physics of Plasma-Based Ion Implantation&Deposition (PBIID)and High Power Impulse Magnetron Sputtering (HIPIMS): A Comparison

Description: The emerging technology of High Power Impulse MagnetronSputtering (HIPIMS) has much in common with the more establishedtechnology of Plasma Based Ion Implantation&Deposition (PBIID):both use pulsed plasmas, the pulsed sheath periodically evolves andcollapses, the plasma-sheath system interacts with the pulse-drivingpower supply, the plasma parameters are affected by the power dissipated,surface atoms are sputtered and secondary electrons are emitted, etc.Therefore, both fields of science and te… more
Date: August 28, 2007
Creator: Anders, Andre
Partner: UNT Libraries Government Documents Department
open access

Analysis of stress sensitivity and its influence on oil productionfrom tight reservoirs

Description: This paper presents a study of the relationship betweenpermeability and effective stress in tight petroleum reservoirformations. Specifically, a quantitative method is developed to describethe correlation between permeability and effective stress, a method basedon the original in situ reservoir effective stress rather than ondecreased effective stress during development. The experimental resultsshow that the relationship between intrinsic permeability and effectivestress in reservoirs in genera… more
Date: August 28, 2007
Creator: Lei, Qun; Xiong, Wei; Yuan, Cui & Wu, Yu-Shu
Partner: UNT Libraries Government Documents Department
open access

Extension of the operating parameters of the two stage light gas gun to velocities below 2 km/sec.

Description: The Joint Actinide Shock Physics Experimental Facility (JASPER) located in area 27 at the Nevada Test Site Has been tasked with providing high accuracy information on the Equation Of State (EOS) and other dynamic properties of weapons grade plutonium and other actinides important to the stockpile stewardship program. In the past 5 years this facility has provided dozens of experimental data points for the accurate determination of pressure density relationship for these materials over a broad p… more
Date: August 28, 2007
Creator: Thoe, R S
Partner: UNT Libraries Government Documents Department
open access

Measurements of the Semileptonic Decays \Bb\to D\ell\nub and \Bb\to D^*\ell\nub Using a Global Fit to D X\ell\nub Final States

Description: Semileptonic {bar B} decays to DX{ell}{bar {nu}} ({ell} = e or {mu}) are selected by reconstructing D{sup 0}{ell} and D{sup +}{ell} combinations from a sample of 230 million {Upsilon}(4S) {yields} B{bar B} decays recorded with the BABAR detector at the PEP-II e{sup +}e{sup -} collider at SLAC. A global fit to these samples in a 3-dimensional space of kinematic variables is used to determine the branching fractions {Beta}(B{sup -} {yields} D{sup 0}{ell}{bar {nu}}) = 2.36 {+-} 0.03 {+-} 0.12% and… more
Date: August 28, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Diagnostics considerations for the inertial confinement approach to controlled thermonuclear fusion power production

Description: It is concluded that although the challenges facing diagnosticians working on the inertial confinement approach to controlled fusion are large and varied, the means potentially available to meet them are more than adequate. No new instrumentation fields need be opened; rather, substantial extensions of those already being explored by workers in ICF will suffice. Also, large contributions may be expected from other technological applications thrusts, as well as from the general, currently rapid … more
Date: August 28, 1978
Creator: Wood, L.
Partner: UNT Libraries Government Documents Department
open access

Design of a materials testing experiment for the INTOR

Description: The United States, Japan, USSR and the European community are jointly participating in the design of an International Tokamak Reactor called INTOR. In support of the US contribution to the INTOR design, the features of an experiment for bulk neutron irradiation damage studies were developed. It is anticipated that materials testing will be an important part of the programmatic mission of INTOR and consequently the requirements for materials testing in INTOR must be identified early in the react… more
Date: August 28, 1981
Creator: Vogel, M.A. & Opperman, E.K.
Partner: UNT Libraries Government Documents Department
open access

Primary creep of UO/sub 2/ above 2000/sup 0/C

Description: A technique for measuring primary creep was developed which facilitates rapid load application to high temperature creep samples. Creep strain measurements for times as short as one second can be made. The strain as a function of time has a logarithmic relationship with a time exponent of 0.7 +- 0.1. Although the resulting expression is in conflict with the normal way of describing the high temperature deformation of fuel under stress, it is possible to incorporate so-called steady state creep … more
Date: August 28, 1979
Creator: Slagle, O. D.
Partner: UNT Libraries Government Documents Department
open access

Description of steam-condensation phenomena during the loss-of-coolant accident. [BWR]

Description: The development and verification of advanced computer models which describe the boiling water reactor (BWR) pressure suppression process for a hypothetical loss-of-coolant accident (LOCA) require a clear description of basic steam condensation phenomena. The GKSS Research Center, in coordination with interested institutions of West Germany and the United States, is currently conducting a test program for such basic research on a multivent BWR-related pressure suppression system. The Lawrence Li… more
Date: August 28, 1980
Creator: McCauley, E.W.; Holman, G.S.; Aust, E.; Schwan, H.; Vollbrandt, J. & Fuerst, H.
Partner: UNT Libraries Government Documents Department
open access

Concentration quenching in Nd-doped glasses

Description: Fluorescence from trivalent Nd in solids is unfortunately quenched by interactions between Nd ions. Thus, laser materials with high Nd concentrations have reduced efficiencies because of this self-quenching, also known as concentration quenching. Nd self-quenching in different crystals and glasses varies considerably. We are therefore investigating this effect in a large number of materials in an effort to: (1) find those materials with long Nd fluorescent lifetimes at high Nd concentrations; a… more
Date: August 28, 1984
Creator: Stokowski, S. E.; Cook, L.; Mueller, H. & Weber, M. J.
Partner: UNT Libraries Government Documents Department
open access

X-ray and neutron sensitivity of imaging plates

Description: No Description Available.
Date: August 28, 2013
Creator: Izumi, N.; Lee, J.; Romano, E.; Stone, G.; Maddox, B.; Ma, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Crystal-Tolerant Glass Approach For Mitigation Of Crystal Accumulation In Continuous Melters Processing Radioactive Waste

Description: High-level radioactive waste melters are projected to operate in an inefficient manner as they are subjected to artificial constraints, such as minimum liquidus temperature (T{sub L}) or maximum equilibrium fraction of crystallinity at a given temperature. These constraints substantially limit waste loading, but were imposed to prevent clogging of the melter with spinel crystals [(Fe, Ni, Mn, Zn)(Fe, Cr){sub 2}O{sub 4}]. In the melter, the glass discharge riser is the most likely location for c… more
Date: August 28, 2012
Creator: Kruger, Albert A.; Rodriguez, Carmen P.; Lang, Jesse B.; Huckleberry, Adam R.; Matyas, Josef & Owen, Antoinette T.
Partner: UNT Libraries Government Documents Department
open access

S-Band Loads for SLAC Linac

Description: The S-Band loads on the current SLAC linac RF system were designed, in some cases, 40+ years ago to terminate 2-3 MW peak power into a thin layer of coated Kanthal material as the high power absorber [1]. The technology of the load design was based on a flame-sprayed Kanthal wire method onto a base material. During SLAC linac upgrades, the 24 MW peak klystrons were replaced by 5045 klystrons with 65+ MW peak output power. Additionally, SLED cavities were introduced and as a result, the peak pow… more
Date: August 28, 2012
Creator: Krasnykh, A.; Decker, F.-J. & LeClair, R.
Partner: UNT Libraries Government Documents Department
open access

Task 1 Steam Oxidation (NETL-US)

Description: A first high pressure test was completed: 293 hr at 267 bar and 670{degrees}C; A parallel 1 bar test was done for comparison; Mass gains were higher for all alloys at 267 bar than at 1 bar; Longer term exposures, over a range of temperatures and pressures, are planned to provide information as to the commercial implications of pressure effects; The planned tests are at a higher combination of temperatures and pressures than in the existing literature. A comparison was made with longer-term lite… more
Date: August 28, 2013
Creator: Holcomb, Gordon R. & Carney, Casey
Partner: UNT Libraries Government Documents Department
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