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Corrosion Evaluation of Tank 40 Leak Detection Box

Description: 'Leak detection from the transfer lines in the tank farm has been a concern for many years because of the need to minimize exposure of personnel and contamination of the environment. The leak detection box (LDB) is one line of defense, which must be maintained to meet this objective. The evaluation of a failed LDB was one item from an action plan aimed at minimizing the degradation of LDBs. The Tank 40 LDB, which failed in service, was dug up and shipped to SRTC for evaluation. During a video i… more
Date: July 29, 1999
Creator: Mickalonis, J.I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Numerical Modeling of Mixing of Chemically Reacting, Non- Newtonian Slurry for Tank Waste Retrieval

Description: The objectives of this study are to investigate interactions among chemical reactions, waste rheology, and slurry mixing occurring during the tank waste retrieval operation and to provide a scientific basis for the waste retrieval decision-making process. Specific objectives are to: (1) Evaluate numerical modeling of non-Newtonian waste with yield strength; (2) Examine reactive transport simulation of tank waste; (3) Conduct numerical modeling analysis of local and global mixing of non-Newtonia… more
Date: June 1, 1999
Creator: Yuen, David A. & Onishi,Yasuo
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Development of an In-Situ Microsensor for the Measurements of Chromium and Uranium in Groundwater at DOE Sites

Description: The goal of this program is to develop, optimize and deploy a silicon-based micromachined stripping analyzer for field monitoring trace levels of chromium and uranium. Such system will integrate the sample-handling steps and necessary chemical reactions (using a flow-injection operation) with the actual adsorptive stripping measurement on a small planar chip. Besides the drastic reduction in the size of the analytical system, such miniaturization should lead to increased speed, minimal reagent … more
Date: June 1, 1999
Creator: Wang, Joseph; Liu, Chung-Chiun & Olsen, Khris B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Flow Visualization of Forced and Natural Convection in Internal Cavities

Description: The goal of this program is to develop innovative flow visualization methods and predictive techniques for energy, mass and momentum transfer in the presence of chemical reactions in the drying and passivation of spent nuclear fuel (SNF) elements.
Date: June 1, 1999
Creator: Crepeau, J. C.; Clarksean, R.; McEligot, D. M. & Guezennec, Y. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Yucca Mountain drift scale test progress report

Description: The Drift Scale Test (DST) is part of the Exploratory Studies Facility (ESF) Thermal Test being conducted underground at the potential high-level nuclear waste repository at Yucca Mountain, Nevada. The purpose of the ESF Thermal Test is to acquire a more in-depth understanding of the coupled thermal, mechanical, hydrological, and chemical processes likely to be encountered in the rock mass surrounding the potential geological repository at Yucca Mountain. These processes are monitored by a mult… more
Date: January 1, 1999
Creator: Apps, J.; Birkholzer, J.T.; Peterson, J. E.; Sonnenthal, E.; Spycher, N.; Tsang, Y. W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Hanford waste tanks - light at the end of the tunnel

Description: The U.S. Department of Energy (DOE) faced several problems in its Hanford Site tank farms in the early nineties. It had 177 waste tanks, ranging in size from 55,000 to 1,100,000 gallons, which contained more than 55 million gallons of liquid and solid high-level radioactive waste (HLW) from a variety of processes. Unfortunately, waste transfer records were incomplete. Chemical reactions going on in the tanks were not totally understood. Every tank had high concentrations of powerful oxidizers i… more
Date: September 29, 1999
Creator: POPPITI, J.A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Nonlinear Waves in Reaction Diffusion Systems: The Effect of Transport Memory

Description: Motivated by the problem of determining stress distributions in granular materials, we study the effect of finite transport correlation times on the propagation of nonlinear wavefronts in reaction diffusion systems. We obtain new results such as the possibility of spatial oscillations in the wavefront shape for certain values of the system parameters and high enough wavefront speeds. We also generalize earlier known results concerning the minimum wavefront speed and shape-speed relationships st… more
Date: November 4, 1999
Creator: Hurd, Alan J.; Kenkre, v. M. & Manne, K. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Numerical Modeling of Coupled Variably-Saturated Fluid Flow and Reactive Transport with Fast and Slow Chemical Reactions

Description: The couplings among chemical reaction rates, advective and diffusive transport in fractured media or soils, and changes in hydraulic properties due to precipitation and dissolution within fractures and in rock matrix are important for both nuclear waste disposal and remediation of contaminated sites. This paper describes the development and application of LEHGC2.0, a mechanistically-based numerical model for simulation of coupled fluid flow and reactive chemical transport including both fast an… more
Date: September 20, 1999
Creator: LI, MING-HSU; SIEGEL, MALCOLM D. & YEH, GOUR-TSYH (GEORGE)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Chemical dynamics in the gas phase : quantum mechanics of chemical reactions.

Description: This research program focuses on both the development and application of accurate quantum mechanical methods to describe gas phase chemical reactions and highly excited molecules. Emphasis is often placed on time-dependent or integrative approaches that, in addition to computational simplifications, yield useful mechanistic insights. Applications to systems of current experimental and theoretical interest are emphasized. The results of these calculations also allow one to gauge the quality of t… more
Date: July 2, 1999
Creator: Gray, S. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Results of plug-flow reactor experiments with crushed tuff at 280C and 300C

Description: We report on the results to date for two plug-flow reactor experiments, PFR-11 and PFR-13, designed to simulate reactive transport chemical and physical processes. These experiments provide a physical model of idealized one dimensional plug flow and chemical reaction using deionized water and crushed Topopah Springs Tuff (Tsw2). Data consist of effluent ion concentrations and pH measurements taken at several times during both experiments and limited mineralogical analysis of post-test solid pha… more
Date: September 2, 1999
Creator: Dibley, M J; Knauss, K G & Rosenberg, N D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Kinetic modeling of non-ideal explosives

Description: We have implemented a Wood-Kirkwood kinetic detonation model based on multi-species equations of state and multiple reaction rate laws. Finite rate laws are used for the slowest chemical reactions, while other reactions are given infinite rates and are kept in constant thermodynamic equilibrium. We model a wide range of ideal and non-ideal composite energetic materials. In addition, we develop an exp-6 equation of state for the product fluids that reproduces a wide range experimental shock Hugo… more
Date: March 1, 1999
Creator: Fried, L. E.; Howard, W. M. & Souers, P. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Development of Alkaline Oxidative Dissolution Methods for Chromium (III) Compounds Present in Hanford Site Tank Sludges

Description: The high-level radioactive waste sludge in the underground storage tanks at the Hanford Site contains various chromium solid phases. Dissolution and removal of chromium from tank waste sludges is desirable prior to high-level waste vitrification because increased volume is required to incorporate the residual chromium. Unfortunately, dissolution of chromium from the sludge to form Cr(OH){sub 4}{sup -} through treatment with heated NaOH solution (also used to dissolve aluminum phases and metathe… more
Date: July 2, 1999
Creator: Delegard, Calvin H.; Krot, N. N.; Shilov, V. P.; Fedoseev, A. M.; Budantseva, N. A.; Nikonov, M. V. et al.
Item Type: Refine your search to only Text
Partner: UNT Libraries Government Documents Department
open access

Effect of Substrate Composition on the Piezoelectric Response of Reactively Sputtered AlN Thin Films

Description: Deposition parameters were found to have a marked effect on piezoelectric response of reactive radio frequency (RF) sputtered AlN thin films. The authors observed peizoelectric response values ranging from {minus}3.5 to +4.2 pm/V for 1 {micro}m thick AlN films deposited onto Ti/Ru electrode stacks. An investigation of the effects of deposition parameters, in particular the nature of the Ru/AlN interface, was conducted. The lag time between deposition of adjacent thin film layers appeared to hav… more
Date: April 21, 1999
Creator: Clem, P. G.; Dimos, D. B.; Gonzales, D. M.; Ruffner, J. A. & Tuttle, B. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Picosecond Electronic Spectroscopy to Determine the Transformation Mechanism for the Pressure-Induced Phase Transition in Shocked CdS

Description: Plate impact, shock wave experiments provide a unique method to investigate the time-dependent mechanisms and the kinetics associated with pressure-induced phenomena, such as chemical reactions and phase transformations. The very rapid and well defined loading conditions associated with plate-impact experiments permit real-time examination of the shock-induced changes. Further, the ability to propagate the shock wave along various crystallographic directions provides the means to perform carefu… more
Date: July 21, 1999
Creator: Knudson, M.D.; Gupta, Y.M. & Kunz, A.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Thermodynamic Model for Acetate, Lactate, and Oxalate Complexation with Am(III), Th(IV), Np(V), and U(VI) Valid to High Ionic Strength

Description: The organic ligands acetate, lactate, oxalate and EDTA have been identified as components of wastes targeted for disposal in the Waste Isolation Pilot Plant (WIPP) located in Southeastern New Mexico. The presence of these ligands is of concern because complexation of the actinides with the ligands may increase dissolved actinide concentrations and impact chemical retardation during transport. The current work considers the complexation of Am(III), Th (IV), Np(V), and U(W) with two of the organi… more
Date: January 15, 1999
Creator: Bynaum, R.V.; Free, S.J. & Moore, R.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Thermochemical Analysis for Purification of Polysilicon Melts

Description: Chemical Equilibrium calculations are presented that are relevant to the purification of molten silicon by gas-blowing. The equilibrium distributions of silicon, boron, phosphorus carbon and iron among the solid, liquid and gas phases are reported for a variety of added chemicals, temperatures and total pressures. The identities of the dominant chemical species for each element in each phase are also provided for these conditions. The added gases examined are O(2), air, water, wet air, HCl, Cl(… more
Date: May 1, 1999
Creator: Ho, Pauline: Gee, James M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

METHODOLOGY FOR EXAMINING SYSTEM AGING DUE TO INTERACTIONS BETWEEN CHEMICALLY INCOMPATIBLE MATERIALS

Description: We start with a stored and unused population of fielded engineered units that are composed of chemically incompatible materials. The units age primarily through heterogeneous chemical reactions between the materials resulting in possible degradation in performance. The engineered units are unused in storage, but may be called into actual service at any time. We sample several units from the population per year and perform a number of non-destructive evaluation (NDE) techniques, such as radiogra… more
Date: April 1, 1999
Creator: DENINGER, J. & TANSKI, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

IMPROVED CORROSION RESISTANCE FOR ALUMINA REFRACTORY

Description: In order to increase the efficiency of advanced coal-fired power systems, higher working fluid temperatures must be reached. Some system surfaces will have to be protected by covering them with corrosion-resistant refractories. Corrosion is the degradation of the material surfaces or grain boundaries by chemical reactions with melts, liquids, or gases causing loss of material and, consequently, a decrease in the strength of the structure. In order to develop methods of reducing corrosion, the m… more
Date: April 30, 1999
Creator: Hurley, John P. & Kleven, Patty L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY

Description: The U.S. Department of Energy (DOE), National Energy Technology Laboratory (NETL), is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal-derived fuel-gas) streams of integrated gasification combined-cycle (IGCC) power systems. The hot gas cleanup work seeks to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs. Hot-gas desulfurization research has focused on… more
Date: July 1, 1999
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

BENCH-SCALE DEMONSTRATION OF HOT-GAS DESULFURIZATION TECHNOLOGY

Description: The U.S. Department of Energy (DOE), Federal Energy Technology Center (FETC), is sponsoring research in advanced methods for controlling contaminants in hot coal gasifier gas (coal-derived fuel-gas) streams of integrated gasification combined-cycle (IGCC) power systems. The hot gas cleanup work seeks to eliminate the need for expensive heat recovery equipment, reduce efficiency losses due to quenching, and minimize wastewater treatment costs. Hot-gas desulfurization research has focused on rege… more
Date: October 1, 1999
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

EXPERIMENTAL INVESTIGATIONS OF THE INTERACTION OF SO(2) WITH MGO.

Description: High resolution adsorption isotherms, temperature programmed desorption (TPD), x-ray diffraction (XRD) and x-ray absorption near edge spectroscopy (XANES) methods were used to investigate the interaction of SO{sub 2} with high quality MgO powders. The results of these investigations indicate that when SO{sub 2} is deposited on MgO in monolayer quantities at temperatures near 100K both SO{sub 2} and SO{sub 4} species form that are not removed by simply pumping on the pre-dosed samples at room te… more
Date: November 29, 1999
Creator: FREITAG,A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Using Perspective to Model Complex Processes

Description: The notion of perspective, when supported in an object-based knowledge representation, can facilitate better abstractions of reality for modeling and simulation. The object modeling of complex physical and chemical processes is made more difficult in part due to the poor abstractions of state and phase changes available in these models. The notion of perspective can be used to create different views to represent the different states of matter in a process. These techniques can lead to a more un… more
Date: April 4, 1999
Creator: Kelsey, R.L. & Bisset, K.R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Closure of the condensed-phase organic-nitrate reaction USQ at hanford

Description: A discovery Unreviewed Safety Question (USQ) was declared on the underground waste storage tanks at the Hanford Site in May 1996. The USQ was for condensed-phase organic-nitrate reactions (sometimes called organic complexant reactions) in the tanks. This paper outlines the steps taken to close the USQ, and resolve the related safety issue. Several processes were used at the Hanford Site to extract and/or process plutonium. These processes resulted in organic complexants (for chelating multivale… more
Date: June 24, 1999
Creator: COWLEY, W.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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