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Application of a World Wide Web technology to environmental remediation (open access)

Application of a World Wide Web technology to environmental remediation

As part of the Formerly Utilized Site Remedial Action Program (FUSRAP), the United States Army Corps of Engineers (USACE), Buffalo District, is responsible for overseeing the remediation of several sites within its jurisdiction. FUSRAP sites are largely privately held facilities that were contaminated by activities associated with the nuclear weapons program in the 1940s, 50s, and 60s. The presence of soils and structures contaminated with low levels of radionuclides is a common problem at these sites. Typically, contaminated materials must be disposed of off-site at considerable expense (up to several hundred dollars per cubic yard of waste material). FUSRAP is on an aggressive schedule, with most sites scheduled for close-out in the next couple of years. Among the multitude of tasks involved in a typical remediation project is the need to inform and coordinate with active stakeholder communities, including local, state, and federal regulators.
Date: March 9, 2000
Creator: Johnson, R. & Durham, L. A.
System: The UNT Digital Library
Automating the management of environmental compliance reporting: Making the complex simple (open access)

Automating the management of environmental compliance reporting: Making the complex simple

Environmental compliance reporting requirements are notoriously complex. This reporting complexity is compounded by organizational and functional complexity at Rocky Mountain Arsenal (RMA), where the Department of the Army has undertaken a multi billion dollar environmental cleanup action. This site is subject to both fixed and contingent federal, state, and local reporting requirements. Management and operation of the site is characterized by numerous organizational layers, and compliance information is generated by many different contractors and subcontractors. This information must be compiled by various managers and reported to either regulators or Department of the Army offices. The RMA Environmental Compliance Office and top-level management must be assured that these reports are being promptly generated and submitted. With over 1,500 individual reporting requirements forecasted for over the next 11 years, the managerial challenge is immense. To facilitate the collation of data and issuance of compliance reports, an intranet-based database is being developed. This database is designed to be available to all personnel with access to the site's environmental compliance intranet. It presents all applicable reporting requirements in an easily sortable format. Information available for each report includes deadlines, report status, recipients, individuals responsible for report generation, and other relevant data fields. Reports can …
Date: March 9, 2000
Creator: Perkins, S.
System: The UNT Digital Library
Biomass Power and State Renewable Energy Policies Under Electric Industry Restructuring (open access)

Biomass Power and State Renewable Energy Policies Under Electric Industry Restructuring

The paper discusses policies that foster renewable energy as enacted by states in response to utility restructuring. In particular, it discusses the role of biomass in these policies.
Date: October 9, 2000
Creator: Porter, K. & Wiser, R.
System: The UNT Digital Library
Bridged polysilsesquioxanes: A molecular based approach for the synthesis of functional hybrid materials (open access)

Bridged polysilsesquioxanes: A molecular based approach for the synthesis of functional hybrid materials

Bridged polysilsesquioxanes (BPS) are a family of hybrid organic-inorganic materials prepared by sol-gel polymerization of molecular building blocks that contain a variable organic component and at least two trifunctional silyl groups. The resulting xerogels and aerogels have physical and mechanical properties that are strongly influenced by the organic bridging group. This talk focuses on the synthesis of functional bridged polysilsesquioxanes. Incorporation of functional groups that respond to chemical, photochemical, or thermal stimuli can provide handles for modifying bulk morphology and/or provide function. These materials can find use as ion exchange media, chromatographic stationary phases, photoresists and high capacity selective chemical absorbents.
Date: May 9, 2000
Creator: SHEA,KENNETH J. & LOY,DOUGLAS A.
System: The UNT Digital Library
Calculation of Hamaker constants in non-aqueous fluid media (open access)

Calculation of Hamaker constants in non-aqueous fluid media

Calculations of the Hamaker constants representing the van der Waals interactions between conductor, resistor and dielectric materials are performed using Lifshitz theory. The calculation of the parameters for the Ninham-Parsegian relationship for several non-aqueous liquids has been derived based on literature dielectric data. Discussion of the role of van der Waals forces in the dispersion of particles is given for understanding paste formulation. Experimental measurements of viscosity are presented to show the role of dispersant truncation of attractive van der Waals forces.
Date: May 9, 2000
Creator: BELL,NELSON S. & DIMOS,DUANE B.
System: The UNT Digital Library
CARBON DIOXIDE AS A FEEDSTOCK. (open access)

CARBON DIOXIDE AS A FEEDSTOCK.

This report is an overview on the subject of carbon dioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbon dioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbon dioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbon dioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting …
Date: December 9, 2000
Creator: CREUTZ,C. & FUJITA,E.
System: The UNT Digital Library
CARBON DIOXIDE AS A FEEDSTOCK. (open access)

CARBON DIOXIDE AS A FEEDSTOCK.

This report is an overview on the subject of carbon dioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbon dioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbon dioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbon dioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting …
Date: December 9, 2000
Creator: CREUTZ,C. & FUJITA,E.
System: The UNT Digital Library
CHEMISTRY OF SO{sub 2} ON MODEL METAL AND OXIDE CATALYSTS: PHOTOEMISSION AND XANES STUDIES (open access)

CHEMISTRY OF SO{sub 2} ON MODEL METAL AND OXIDE CATALYSTS: PHOTOEMISSION AND XANES STUDIES

High-resolution synchrotron based photoemission and x-ray absorption spectroscopy have been used to study the interaction of SO{sub 2} with a series of metals and oxides. The chemistry of SO{sub 2} on metal surfaces is rich. At low coverages, the molecule fully decomposes into atomic S and O. At large coverages, the formation of SO{sub 3} and SO{sub 4} takes place. The following sequence was found for the reactivity of the metals towards SO{sub 2}: Pt {approx} Rh < Ru < Mo << Zn, Sn, Cs. Alloying can be useful for reducing the chemical affinity of a metal for SO{sub 2} and controlling S poisoning. Pd atoms bonded to Rh and Pt atoms bonded to Sn interact weakly with SO{sub 2}. In general, SO{sub 2} mainly reacts with the O centers of metal oxides. SO{sub 4} is formed on CeO{sub 2} and SO{sub 3} on ZnO. On these systems there is no decomposition of SO{sub 2}. Dissociation of the molecule is observed after introducing a large amount of Ce{sup 3+} sites in ceria, or after depositing Cu or alkali metals on the oxide surfaces. These promote the catalytic activity of the oxides during the destruction of SO{sub 2}.
Date: July 9, 2000
Creator: Rodriguez, J. A.; Jirsak, T.; Chaturvedi, S.; Hrbek, J.; Freitag, A. & Larese, J. Z.
System: The UNT Digital Library
Comparison of Finite Element Predictions to Measurements from the Sandia Microslip Experiment (open access)

Comparison of Finite Element Predictions to Measurements from the Sandia Microslip Experiment

When embarking on an experimental program for purposes of discovery and understanding, it is only prudent to use appropriate analysis tools to aid in the discovery process. Due to the limited scope of experimental measurement analytical results can significantly complement the data after a reasonable validation process has occurred. In this manner the analytical results can help to explain certain measurements, suggest other measurements to take and point to possible modifications to the experimental apparatus. For these reasons it was decided to create a detailed nonlinear finite element model of the Sandia Microslip Experiment. This experiment was designed to investigate energy dissipation due to microslip in bolted joints and to identify the critical parameters involved. In an attempt to limit the microslip to a single interface a complicated system of rollers and cables was devised to clamp the two slipping members together with a prescribed normal load without using a bolt. An oscillatory tangential load is supplied via a shaker. The finite element model includes the clamping device in addition to the sequence of steps taken in setting up the experiment. The interface is modeled using Coulomb friction requiring a modest validation procedure for estimating the coefficient of friction. Analysis …
Date: November 9, 2000
Creator: LOBITZ,DONALD W.; GREGORY,DANNY LYNN & SMALLWOOD,DAVID O.
System: The UNT Digital Library
Comparison of imaging spectrometers (open access)

Comparison of imaging spectrometers

Realistic signal to noise performance estimates for the various types of instruments being considered for NGST are compared, based on the point source detection values quoted in the available ISIM final reports. The corresponding sensitivity of the various types of spectrometers operating in a full field imaging mode, for both emission line objects and broad spectral distribution objects, is computed and displayed. For the purpose of seeing the earliest galaxies, or the faintest possible emission line sources, the imaging Fourier transform spectrometer emerges superior to all others, by orders of magnitude in speed.
Date: January 9, 2000
Creator: Bennett, C
System: The UNT Digital Library
Comparison of mechanical properties of glass-bonded sodalite and borosilicate glass high-level waste forms (open access)

Comparison of mechanical properties of glass-bonded sodalite and borosilicate glass high-level waste forms

Argonne National Laboratory has developed a glass-bonded sodalite waste form to immobilize the salt waste stream from electrometallurgical treatment of spent nuclear fuel. The waste form consists of 75 vol.% crystalline sodalite and 25 vol.% glass. Microindentation fracture toughness measurements were performed on this material and borosilicate glass from the Defense Waste Processing Facility using a Vickers indenter. Palmqvist cracking was confined for the glass-bonded sodalite waste form, while median-radial cracking occurred in the borosilicate glass. The elastic modulus was measured by an acoustic technique. Fracture toughness, microhardness, and elastic modulus values are reported for both waste forms.
Date: May 9, 2000
Creator: O'Holleran, T. P.; DiSanto, T.; Johnson, S. G. & Goff, K. M.
System: The UNT Digital Library
Component Technology for High-Performance Scientific Simulation Software (open access)

Component Technology for High-Performance Scientific Simulation Software

We are developing scientific software component technology to manage the complexity of modem, parallel simulation software and increase the interoperability and re-use of scientific software packages. In this paper, we describe a language interoperability tool named Babel that enables the creation and distribution of language-independent software libraries using interface definition language (IDL) techniques. We have created a scientific IDL that focuses on the unique interface description needs of scientific codes, such as complex numbers, dense multidimensional arrays, complicated data types, and parallelism. Preliminary results indicate that in addition to language interoperability, this approach provides useful tools for thinking about the design of modem object-oriented scientific software libraries. Finally, we also describe a web-based component repository called Alexandria that facilitates the distribution, documentation, and re-use of scientific components and libraries.
Date: November 9, 2000
Creator: Epperly, T; Kohn, S & Kumfert, G
System: The UNT Digital Library
Computational fluid dynamics simulations of a glass melting furnace (open access)

Computational fluid dynamics simulations of a glass melting furnace

The glass production industry is one of the major users of natural gas in the US, and approximately 75% of the energy produced from natural gas is used in the melting process. Industrial scale glass melting furnaces are large devices, typically 5 or more meters wide, and twice as long. To achieve efficient heat transfer to the glass melt below, the natural gas flame must extend over a large portion of the glass melt. Therefore modern high efficiency burners are not used in these furnaces. The natural gas is injected as a jet, and a jet flame forms in the flow of air entering the furnace. In most current glass furnaces the energy required to melt the batch feed stock is about twice the theoretical requirement. An improved understanding of the heat transfer and two phase flow processes in the glass melt and solid batch mix offers a substantial opportunity for energy savings and consequent emission reductions. The batch coverage form and the heat flux distribution have a strong influence on the glass flow pattern. This flow pattern determines to a significant extent the melting rate and the quality of glass.
Date: May 9, 2000
Creator: Egelja, A. & Lottes, S. A.
System: The UNT Digital Library
Current status and future prospects for the PVMaT project (open access)

Current status and future prospects for the PVMaT project

The goals of the Photovoltaic Manufacturing Technology project (PVMaT) are to help the US PV industry improve photovoltaic manufacturing processes and equipment; accelerate manufacturing cost reductions for PV modules, balance-of-systems components, and integrated systems; increase commercial product performance and reliability; and enhance the investment opportunities for substantial scale-ups of US-based PV manufacturing plant capacities. PVMaT is in its ninth year of implementation, and subcontracts have been completed from four solicitations for R and D on manufacturing process problems. They are in the second year of subcontracts for a fifth PVMaT solicitation. Based on the latest (1998) data from ten PVMaT industrial participants, the average direct manufacturing cost for these producers has been reduced by 29%--from $4.08 to $2.91 per peak watt since 1992--and there has also been a more than five-fold increase in manufacturing capacity-from 13.1 to 73.3 megawatts. The authors believe that continuing R and D on manufacturing processes contributes significantly to expeditious reductions in PV manufacturing costs, and they identify areas for future R and D.
Date: February 9, 2000
Creator: Witt, C. E.; Mitchell, R. L.; Symko-Davies, M.; Thomas, H. P.; King, R. & Ruby, D. S.
System: The UNT Digital Library
DD Neutron Yield Measurements on Z Using Lead Probes (open access)

DD Neutron Yield Measurements on Z Using Lead Probes

A series of inertial confinement fusion (ICF) capsule experiments were run on the Z machine at Sandia's Pulsed Power directorate. These experiments were designed specifically to implode a 2 mm diameter hollow plastic capsule filled with deuterium gas. The implosion of the capsule should raise the temperature (kinetic energy) of the deuterium gas ions, which will interact with each other and produce 2.45 MeV fusion neutrons. The author is reporting on one diagnostic technique used to measure the yield of these fusion neutrons. The technique chosen to measure the DD neutron yield is the use of lead (Pb) probe detectors. The assignment was to calibrate two detectors for the 2.50-MeV neutrons produced by the deuterium-deuterium fusion reactions on Z. The author introduces ICF, and then describes the theory, the design, and the calibration of the lead probe. Finally, she presents the results of the ICF experiments and explain the difficulties inherent in analyzing the data.
Date: August 9, 2000
Creator: GERKEN,ERICA S.
System: The UNT Digital Library
Defect structure of indium tin oxide and its relationship to conductivity (open access)

Defect structure of indium tin oxide and its relationship to conductivity

Doping In{sub 2}O{sub 3} with tin results in an improved transparent conducting oxide (TCO). Although indium tin oxide (ITO) is the most frequently used commercial TCO, its defect structure is still uncertain. Previously, its defect chemistry has been inferred based on the conductivity of the material. To directly study the defect structure of ITO, the authors prepared powders under different processing environments and performed neutron powder diffraction. Structural information was obtained by performing Rietveld analysis. The results include positions of the atoms, their thermal displacements, the fractional occupancy of the defect oxygen site, and the fractional occupancies of Sn on each of the two nonequivalent cation sites, showing a strong preference for the b site. These structural results are correlated with the measured electrical properties of the same samples.
Date: May 9, 2000
Creator: Gonzalez, G. B.; Cohen, J. B.; Hwang, J.-H.; Mason, T. O.; Hodges, J. P. & Jorgensen, J. D.
System: The UNT Digital Library
Degradation of EBR-II driver fuel during wet storage (open access)

Degradation of EBR-II driver fuel during wet storage

Characterization data are reported for sodium bonded EBR-II reactor fuel which had been stored underwater in containers since the 1981--1982 timeframe. Ten stainless steel storage containers, which had leaked water during storage due to improper sealing, were retrieved from the ICPP-603 storage basin at the Idaho National Engineering and Environmental Laboratory (INEEL) in Idaho. In the container chosen for detailed destructive analysis, the stainless steel cladding on the uranium alloy fuel had ruptured and fuel oxide sludge filled the bottom of the container. Headspace gas sampling determined that greater than 99% hydrogen was present. Cesium 137, which had leached out of the fuel during the aqueous corrosion process, dominated the radionuclide source term of the water. The metallic sodium from the fuel element bond had reacted with the water, forming a concentrated caustic solution of NaOH.
Date: March 9, 2000
Creator: Pahl, R. G.
System: The UNT Digital Library
Development of a coupled dynamics code with transport theory capability and application to accelerator driven systems transients (open access)

Development of a coupled dynamics code with transport theory capability and application to accelerator driven systems transients

The VARIANT-K and DIF3D-K nodal spatial kinetics computer codes have been coupled to the SAS4A and SASSYS-1 liquid metal reactor accident and systems analysis codes. SAS4A and SASSYS-1 have been extended with the addition of heavy liquid metal (Pb and Pb-Bi) thermophysical properties, heat transfer correlations, and fluid dynamics correlations. The coupling methodology and heavy liquid metal modeling additions are described. The new computer code suite has been applied to analysis of neutron source and thermal-hydraulics transients in a model of an accelerator-driven minor actinide burner design proposed in an OECD/NEA/NSC benchmark specification. Modeling assumptions and input data generation procedures are described. Results of transient analyses are reported, with emphasis on comparison of P1 and P3 variational nodal transport theory results with nodal diffusion theory results, and on significance of spatial kinetics effects.
Date: March 9, 2000
Creator: Cahalan, J. E.; Ama, T.; Palmiotti, G.; Taiwo, T. A. & Yang, W. S.
System: The UNT Digital Library
Development of a Programming Adapter for a Classified-Data Processor Device (open access)

Development of a Programming Adapter for a Classified-Data Processor Device

This summer, the author was tasked with the development of a design and prototype for a Programming Adapter (PA). This device must interface to a specialized cluster of computers at a US Air Force programming station. The PA is a command/response system capable of recognizing commands from a host Programming Computer (PC) generating a response to these commands according to design requirements. The PA must also route classified serial data between a programming station and any target devices on the PA without compromising the data. In this manner, classified data can pass through the adapter, but when data transfer is complete, the PA can be handled as an unclassified piece of hardware.
Date: August 9, 2000
Creator: Perea, Dominic A.
System: The UNT Digital Library
The Development of the Yucca Mountain Project Feature, Event, and Process (FEP) Database (open access)

The Development of the Yucca Mountain Project Feature, Event, and Process (FEP) Database

None
Date: November 9, 2000
Creator: FREEZE,GEOFF; SWIFT,PETER N. & BRODSKY,NANCY S.
System: The UNT Digital Library
Device characteristics of the PnP AlGaAs/InGaAsN/GaAs double heterojunction bipolar transistor (open access)

Device characteristics of the PnP AlGaAs/InGaAsN/GaAs double heterojunction bipolar transistor

The authors have demonstrated a functional PnP double heterojunction bipolar transistor (DHBT) using AlGaAs, InGaAsN, and GaAs. The band alignment between InGaAsN and GaAs has a large {triangle}E{sub C} and a negligible {triangle}E{sub V}, and this unique characteristic is very suitable for PnP DHBT applications. The metalorganic vapor phase epitaxy (MOCVD) grown Al{sub 0.3}Ga{sub 0.7}As/In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01}/GaAs PnP DHBT is lattice matched to GaAs and has a peak current gain of 25. Because of the smaller bandgap (Eg = 1.20 eV) of In{sub 0.03}Ga{sub 0.97}As{sub 0.99}N{sub 0.01} used for the base layer, this device has a low V{sub ON} of 0.79 V, which is 0.25 V lower than in a comparable Pnp AlGaAs/GaAs HBT. And because GaAs is used for the collector, its BV{sub CEO} is 12 V, consistent with BV{sub CEO} of AlGaAs/GaAs HBTs of comparable collector thickness and doping level.
Date: February 9, 2000
Creator: Chang, Ping-Chih; Li, N. Y.; Laroche, J. R.; Baca, Albert G.; Hou, H. Q. & Ren, F.
System: The UNT Digital Library
Differencing Algorithms for Material Interfaces in Two-Phase Darcy Flow (open access)

Differencing Algorithms for Material Interfaces in Two-Phase Darcy Flow

None
Date: November 9, 2000
Creator: REED,ALFRED W.
System: The UNT Digital Library
Digitally Marking RSA Moduli (open access)

Digitally Marking RSA Moduli

The moduli used in RSA (see [5]) can be generated by many different sources. The generator of that modulus (assuming a single entity generates the modulus) knows its factorization. They would have the ability to forge signatures or break any system based on this moduli. If a moduli and the RSA parameters associated with it were generated by a reputable source, the system would have higher value than if the parameters were generated by an unknown entity. So for tracking, security, confidence and financial reasons it would be beneficial to know who the generator of the RSA modulus was. This is where digital marking comes in. An RSA modulus ia digitally marked, or digitally trade marked, if the generator and other identifying features of the modulus (such as its intended user, the version number, etc.) can be identified and possibly verified by the modulus itself. The basic concept of digitally marking an RSA modulus would be to fix the upper bits of the modulus to this tag. Thus anyone who sees the public modulus can tell who generated the modulus and who the generator believes the intended user/owner of the modulus is.
Date: October 9, 2000
Creator: Johnston, A. M.
System: The UNT Digital Library
The Dynamic Competition Between Stress Generation and Relaxation Mechanisms During Coalescence of Volmer-Weber Thin Films (open access)

The Dynamic Competition Between Stress Generation and Relaxation Mechanisms During Coalescence of Volmer-Weber Thin Films

None
Date: October 9, 2000
Creator: Floro, J. A.; Hearne, S. J.; Hunter, J. A.; Kotula, P. G.; Chason, E.; Seel, S. C. et al.
System: The UNT Digital Library