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AX Tank Farm tank removal study

Description: This report considers the feasibility of exposing, demolishing, and removing underground storage tanks from the 241-AX Tank Farm at the Hanford Site. For the study, it was assumed that the tanks would each contain 360 ft{sup 3} of residual waste (corresponding to the one percent residual Inventory target cited in the Tri-Party Agreement) at the time of demolition. The 241-AX Tank Farm is being employed as a ''strawman'' in engineering studies evaluating clean and landfill closure options for Ha… more
Date: October 14, 1998
Creator: SKELLY, W.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Damage to III-V Devices During Electron Cyclotron Resonance Chemical Vapor Deposition

Description: GaAs-based metal semiconductor field effect transistors (MESFETS), heterojunction bipolar transistors (HBTs) and high electron mobility transistors (HEMTs) have been exposed to ECR SiJ&/NH3 discharges for deposition of SiNX passivating layers. The effect of source power, rf chuck power, pressure and plasma composition have been investigated. Effects due to both ion damage and hydrogenation of dopants are observed. For both HEMTs and MESFETS there are no conditions where substantial increases in… more
Date: October 14, 1998
Creator: Abernathy, C.R.; Hahn, Y.B.; Hays, D.C.; Johnson, D.; Lee, J.W.; MacKenzie, K. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radionuclide Distribution Coefficients for Sediments Collected from Borehole 299-E17-21: Final Report for Subtask 1a

Description: Over 360 distribution coefficients (KJ for cesium, iodine, selenium, Strontium, technetium, and uranium were measured in fiscal year 1998 using 20 sediments collected fkom borehole 299-El 7-21 on the Hanford Site as part of the Immobilized Low-Activity Waste-Performance Assessment (ILAW-PA). Additionally, the pH and cation-exchange capacity (a measure of the total quantity of cations that a sediment can adsorb) of these sediment samples were measured. The sediment samples originated from the Ha… more
Date: October 14, 1998
Creator: Kaplan, D. I.; Kutynakov, I. V. & Parker, K. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Performance Assessment in Support of the 1996 Compliance Certification Application for the Waste Isolation Pilot Plant

Description: The conceptual and computational structure of a performance assessment (PA) for the Waste Isolation Pilot Plant (WIPP) is described. Important parts of thk structure are @ maintenance of a separation between stochastic (i.e., aleatory) and subjective (i.e., epistemic) uncertain, with stochastic uncefinty arising from the many possible disruptions that could occur over the 10,000 Y regulatory period fiat applies to the WIPP and subjective uncertainty arising from `the imprecision with which many… more
Date: October 14, 1998
Creator: Anderson, D. R.; Basabilvazo, G.; Helton, J. C.; Jow, H. -N. & Marietta, M. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nuclear analysis of the chornobyl fuel containing masses with heterogeneous fuel distribution.

Description: Although significant data has been obtained on the condition and composition of the fuel containing masses (FCM) located in the concrete chambers under the Chernobyl Unit 4 reactor cavity, there is still uncertainty regarding the possible recriticality of this material. The high radiation levels make access extremely difficult, and most of the samples are from the FCM surface regions. There is little information on the interior regions of the FCM, and one cannot assume with confidence that the … more
Date: October 14, 1998
Creator: Turski, R. B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Metrology of a mirror at the Advanced Photon Source : comparison between optical and x-ray measurements.

Description: This paper describes metrology of a vertically focusing mirror on the bending magnet beamline in sector-1 of the Advanced Photon Source, Argonne National Laboratory. The mirror was evaluated using measurements from both an optical long trace profiler and x-rays. Slope error profiles obtained with the two methods were compared and were found to be in a good agreement. Further comparisons were made between x-ray measurements and results from the SHADOW ray-tracing code.
Date: October 14, 1998
Creator: Assoufid, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurement of the CP asymmetry parameter sin(2{beta}) at CDF.

Description: We present a measurement of the time-dependent asymmetry in the rate for {bar B}{sub d}{sup 0} versus B{sub d}{sup 0} decays to J/{psi}K{sub S}{sup 0}. In the context of the Standard Model this is interpreted as a measurement of the CP-violation parameter sin(2{beta}). A total of 198 {+-} 17 B{sub d}{sup 0}/{bar B}{sub d}{sup 0} decays were observed in p{bar p} collisions at {radical}s = 1.8 TeV by the CDF detector at the Fermilab Tevatron. The initial b-flavor is determined by a same side flav… more
Date: October 14, 1998
Creator: LeCompte, T. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Solvent extraction separation of trivalent lanthanide and actinide ions using an aqueous aminomethanediphosphonic acid.

Description: The possibility of separating the trivalent lanthanides, represented by EU{sup 3+}, and actinides, represented by Cf{sup 3+}, using HDEHP in toluene and an aqueous phase containing N-piperidinomethane-1,1-diphosphotic acid, PMDPA, has been investigated. This modified aqueous phase offers potential advantages over the diethylenetriaminepentaacetic acid based TALSPEAK process because of the improved complexation properties of PMDPA in acidic solutions, and the ability to decompose PMDPA before di… more
Date: October 14, 1998
Creator: Jensen, M. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Trifluoromethylmetallate anions as components of molecular charge transfer salts and superconductors.

Description: Whereas polymeric and common inorganic anions frequently deprive the synthetic chemist of a chance to modify a charge transfer salt's structure through anion alterations, discrete organometallic anions provide a vast opportunity to probe the structure/property correlations of a material through rational synthetic methods. We have recently undertaken a research effort aimed at the crystallization of conducting charge transfer salts which possess modifiable, organometallic anions as the charge co… more
Date: October 14, 1998
Creator: Schlueter, J. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Contact Hysteresis and Friction of Alkanethiol SAMs on Au

Description: Nanoindentation has been combhed with nanometer-scale friction measurements to identi~ dissipative mechanisms responsible for friction in hexadecanethiol self-assembled monolayer on Au. We have demonstrated that friction is primarily due to viscoelastic relaxations within the films, which give rise to contact hysteresis when deformation rates are within the ranges of 5 and 200 k. We observe that this contact hysteresis increases with exposure to air such that the friction coefficient increases … more
Date: October 14, 1998
Creator: Houston, J. E. & Kiely, J. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Effect of Temperature on GaGdO/GaN Metal Oxide Semiconductor Field Effect Transistors

Description: GaGdO was deposited on GaN for use as a gate dielectric in order to fabricate a depletion metal oxide semiconductor field effect transistor (MOSFET). This is the fmt demonstration of such a device in the III-Nitride system. Analysis of the effect of temperature on the device shows that gate leakage is significantly reduced at elevated temperature relative to a conventional metal semiconductor field effeet transistor (MESFET) fabricated on the same GaN layer. MOSFET device operation in fact impr… more
Date: October 14, 1998
Creator: Abernathy, C. R.; Baca, A.; Chu, S. N. G.; Hong, M.; Lothian, J. R.; Marcus, M. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Turbulence studies in Tokamak boundary plasmas with realistic divertor geometry

Description: Results are presented from the 3D nonlocal electromagnetic turbulence code BOUT [1] and the linearized shooting code BAL[2] to study turbulence in tokamak boundary plasmas and its relationship to the L-H transition, in a realistic divertor plasma geometry. The key results include: (1) the identification of the dominant, resistive X-point mode in divertor geometry and (2) turbulence suppression in the L-H transition by shear in the ExB drift speed, ion diamagnetism and finite polarization. Based… more
Date: October 14, 1998
Creator: Xu, X.Q.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

The use of WIMS-ANL lumped fission product cross sections for burned core analysis with the MCNP Monte Carlo code.

Description: Most Monte Carlo neutronics analyses are performed for fresh cores. To model snapshots of the cores at different stages during burnup using MCNP, a method is presented that uses lumped fission product (LFP) cross sections generated by the WIMS-ANL code and processed for use in MCNP. Results of analyses for four very different reactor cores using MTR-type and Russian-designed fuel assemblies, with LEU and HEU fuels, are provided to demonstrate the use of this method.
Date: October 14, 1998
Creator: Hanan, N. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Fusion research: the past is prologue

Description: At this juncture fusion research can be viewed as being at a turning point, a time to review its past and to imagine its future. Today, almost 50 years since the first serious attempts to address the daunting problem of achieving controlled fusion, we have both an opportunity and a challenge. Some predictions place fusion research today at a point midway between its first inception and its eventual maturation - in the middle of the 21st century - when fusion would become a major source of energ… more
Date: October 14, 1998
Creator: Post, R F
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Simulation of ion-temperature-gradient turbulence in tokamaks

Description: Results are presented from nonlinear gyrokinetic simulations of toroidal ion temperature gradient (ITG) turbulence and transport. The gyrokinetic simulations are found to yield values of the thermal diffusivity significantly lower than gyrofluid or IFS-PPPL-model predictions. A new phenomenon of nonlinear effective critical gradients larger than the linear instability threshold gradients is observed, and is associated with undamped flux-surface-averaged shear flows. The nonlinear gyrokineic cod… more
Date: October 14, 1998
Creator: Cohen, B I; Dimits, A M; Kim, C; Mattor, N; Nevins, W M; Parker, S E et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transformation of Pb(II) from Cerrusite to Chloropyromorphite in the Presence of Hydroxyapatite under Varying Conditions of pH

Description: Cerrusite (PbC03) is soluble under acidic conditions and considered to be a highly bioavailable soil Pb species. In this study, synthetic cerrusite and hydroxyapatite [Ca5(P04)30H] were reacted under constant and dynamic pH conditions with various P/Pb molar ratios in an attempt to evaluate the effect of reaction kinetics on the formation of chloropyromorphite (Pb5(P04)3Cl) and solubilization of Pb. Under constant pH conditions, dissolution rates of both cerrusite and apatite were rapid when pH… more
Date: October 14, 1998
Creator: Ryan, J.A. & Zhang, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Simulated effects of elevated CO{sub 2} on nitrogen cycling using the NuCM model

Description: The interactions between elevated CO{sub 2} and N cycling were explored using simulations generated by the Nutrient Cycling Model (NuCM) for a Pinus taeda site at Duke, North Carolina and a mixed deciduous site at Walker Branch, Tennessee. The simulations tested whether N limitation would prevent growth increase in response to elevated CO{sub 2} and whether growth response to CO{sub 2} in N-limited systems could be facilitated by increased biomass/N (reduced concentration) and/or increased litt… more
Date: October 14, 1998
Creator: Johnson, D.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

TSD-DOSE: A radiological dose assessment model for treatment, storage, and disposal facilities

Description: Past practices at US Department of Energy (DOE) field facilities resulted in the presence of trace amounts of radioactive materials in some hazardous chemical wastes shipped from these facilities. In May 1991, the DOE Office of Waste Operations issued a nationwide moratorium on shipping all hazardous waste until procedures could be established to ensure that only nonradioactive hazardous waste would be shipped from DOE facilities to commercial treatment, storage, and disposal (TSD) facilities. … more
Date: October 14, 1998
Creator: Pfingston, M.; Arnish, J.; LePoire, D. & Chen, S. Y.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A neutronics feasibility study for the LEU conversion of Poland's Maria research reactor.

Description: The MARIA reactor is a high-flux multipurpose research reactor which is water-cooled and moderated with both beryllium and water. Standard HEU (80% {sup 235}U)fuel assemblies consist of six concentric fuel tubes of a U-Al alloy clad in aluminum. Although the inventory of HEU (80%) fuel is nearly exhausted, a supply of highly-loaded 36%-enriched fuel assemblies is available at the reactor site. Neutronic equilibrium studies have been made to determine the relative performance of fuels with enric… more
Date: October 14, 1998
Creator: Bretscher, M. M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Upgrades to the WIMS-ANL code.

Description: The dusty old source code in WIMS-D4M has been completely rewritten to conform more closely with current FORTRAN coding practices. The revised code contains many improvements in appearance, error checking and in control of the output. The output is now tabulated to fit the typical 80 column window or terminal screen. The Segev method for resonance integral interpolation is now an option. Most of the dimension limitations have been removed and replaced with variable dimensions within a compile-t… more
Date: October 14, 1998
Creator: Woodruff, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Formation of Pyromorphite in Anglesite-Hydroxyapatite Suspensions Under Varying pH Conditions

Description: Addition of phosphate to lead [Pb(ll)l-cOntarninated soil to immobilize soil Pb by formation of pyromorphite has been proposed as an alternative remediation technique. Lead sulfate (PbS04, anglesite), a Pb-bearing form found in contaminated soils and wastes, was reacted with a synthetic phosphate mineral, hydroxyapa$te [Ca5(PO& OH], under constant pH (PH 2-7) and simulated gastric pH conditions (PH varied from 2 to 7 within 30 rein) to assess the effects of reaction kinetics on the formation ra… more
Date: October 14, 1998
Creator: Ryan, J.A. & Zhang, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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