States

The Consequences of Surface Confinement on Free Radical Chemistry (open access)

The Consequences of Surface Confinement on Free Radical Chemistry

Mass transport limitations impact the thermochemical processing of fossil and renewable energy resources, which involves the breakdown of cross-linked, macromolecular networks. To Investigate the molecular level details of the consequences of molecular confinement on high temperature (275-500°C) free-radical reaction pathways, we have been examining the pyrolysis of model compounds attached to the surface of non-porous silica nanoparticles through a thermally robust Si-O-C<sub>aryl</sub>, tetha. Pyrolysis of silica-immobilized diphenylalkanes and related ethers have been studied in detail and compared with the corresponding behavior in fluid phases. The diffusional constraints can lead to reduced rates of radical termination on the surface, and enhancement of neophyl-like rearrangements, cyclization-dehydrogenation pathways, and <i>ipso-</i> aromatic substitutions. Furthermore, studies of two-component surfaces have revealed the importance of a radical relay mechanism involving rapid serial hydrogen transfer steps resulting from the molecular pre-organization on the low fractal dimension silica surface. Key findings are reviewed in this paper, and the implications of these results for fuel processing are described.
Date: August 22, 1999
Creator: Birtt, P.F. & Buchanan, A. C., III
Object Type: Article
System: The UNT Digital Library
Material Property Measurement of Metallic Parts using the INEEL Laser Ultrasonic Camera (open access)

Material Property Measurement of Metallic Parts using the INEEL Laser Ultrasonic Camera

Ultrasonic waves form a useful nondestructive evaluation (NDE) probe for determining physical, microstructural, and mechanical properties of materials and parts. Noncontacting laser ultrasonic methods are desired for remote measurements and on-line manufacture process monitoring. Researchers at the Idaho National Engineering & Environmental Laboratory (INEEL) have developed a versatile new method for detection of ultrasonic motion at surfaces. This method directly images, without the need for scanning, the surface distribution of subnanometer ultrasonic motion. By eliminating the need for scanning over large areas or complex parts, the inspection process can be greatly speeded up. Examples include measurements on parts with complex geometries through resonant ultrasound spectroscopy and of the properties of sheet materials determined through anisotropic elastic Lamb wave propagation. The operation and capabilities of the INEEL Laser Ultrasonic Camera are described along with measurement results.
Date: August 22, 1999
Creator: Telschow, K. L.; Schley, R. S.; Watson, S. M. & Deason, V. A.
Object Type: Article
System: The UNT Digital Library
Mechanistic Investigation into the Decarboxylation of Aromatic Carboxylic Acids (open access)

Mechanistic Investigation into the Decarboxylation of Aromatic Carboxylic Acids

It has been proposed that carboxylic acids and carboxylates are major contributors to cross-linking reactions in low-rank coals and inhibit its thermochemical processing. Therefore, the thermolysis of aromatic carboxylic acids was investigated to determine the mechanisms of decarboxylation at temperatures relevant to coal processing, and to determine if decarboxylation leads to cross-linking (i.e., formation of more refractory products). From the thcrmolysis of simple and polymeric coal model compounds containing aromatic carboxylic acids at 250-425 �C, decarboxylation was found to occur primarily by an acid promoted ionic pathway. Carboxylate salts were found to enhance the decarboxylation rate, which is consistent with the proposed cationic mechanism. Thermolysis of the acid in an aromatic solvent, such as naphthalene, produced a small amount of arylated products (~5 mol%)), which constitute a low-temperature cross-link. These arylated products were formed by the rapid decomposition of aromatic anhydrides, which are in equilibrium with the acid. These anhydrides decompose by a free radical induced decomposition pathway to form atyl radicals that can add to aromatic rings to form cross-links or abstract hydrogen. Large amounts of CO were formed in the thennolysis of the anhydrides which is consistent with the induced decomposition pathway. CO was also formed in the …
Date: August 22, 1999
Creator: Britt, P. F.; Buchanan, A. C., III; Eskay, T. P. & Mungall, W. S.
Object Type: Article
System: The UNT Digital Library
Photosynthetic Hydrogen and Oxygen Production by Green Algae (open access)

Photosynthetic Hydrogen and Oxygen Production by Green Algae

Photosynthesis research at Oak Ridge National Laboratory is focused on hydrogen and oxygen production by green algae in the context of its potential as a renewable fuel and chemical feed stock. Beginning with its discovery by Gaffron and Rubin in 1942, motivated by curiosity-driven laboratory research, studies were initiated in the early 1970s that focused on photosynthetic hydrogen production from an applied perspective. From a scientific and technical point of view, current research is focused on optimizing net thermodynamic conversion efficiencies represented by the Gibbs Free Energy of molecular hydrogen. The key research questions of maximizing hydrogen and oxygen production by light-activated water splitting in green algae are: (1) removing the oxygen sensitivity of algal hydrogenases; (2) linearizing the light saturation curves of hotosynthesis throughout the entire range of terrestrial solar irradiance-including the role of bicarbonate and carbon dioxide in optimization of photosynthetic electron transpor;t and (3) constructing real-world bioreactors, including the generation of hydrogen and oxygen against workable back pressures of the photoproduced gases.
Date: August 22, 1999
Creator: Greenbaum, E. & Lee, J.W.
Object Type: Article
System: The UNT Digital Library
Rapid Risk-Based Evaluation of Competing Conceptual Designs (open access)

Rapid Risk-Based Evaluation of Competing Conceptual Designs

In this paper, the authors have shown how a qualitative analysis can provide good input to a risk reduction design problem. Traditionally qualitative analyses such as the FMEA can be supplemented by qualitative fault trees and event trees to produce logic models of the accident sequences for the different design options. These models can be compared using rule-based manipulations of qualitative branch point probabilities. A qualitative evaluation of other considerations such as collateral safety effects, operational impacts and worker-safety impacts can provide a more complete picture of the trade-off between options. The authors believe that their risk-reduction analysis approach that combines logic models with qualitative and possibility metrics provides an excellent tool for incorporating safety concerns rapidly and effectively into a conceptual design evaluation.
Date: August 22, 1999
Creator: Bott, T. F. & Butner, J. M.
Object Type: Article
System: The UNT Digital Library
Radiation hardened fiber optics for fusion reactor diagnostic systems. Final technical report (open access)

Radiation hardened fiber optics for fusion reactor diagnostic systems. Final technical report

This final report comprises a brief synopsis of the following original papers published in refereed journals. For further details, these papers themselves should be consulted. (1) ``Fast-neutron radiation effects in a silica-core optical fiber studied by a CCD-camera spectrometer,`` D.L. Griscom, M.E. Gingerich, E.J. Friebele, M. Putnam, and W. Unruh, Appl. Optics 33, 1022-1028 (1994). (2) ``Radiation hardening of pure-silica-core optical fibers by ultra-high-dose {gamma}-ray pre-irradiation,`` D.L. Griscom, J. Appl. Phys. 77, 5008-5013 (1995). (3) ``{gamma}-radiation resistance of aluminum-coated all-silica optical fibers fabricated using different types of silica in the core,`` D.L. Griscom, K.M. Goland, A.L. Tomashuk, D.V.; Pavlov, and Yu.A. Tarabrin, Appl. Phys. Lett. 69, 322-324 (1996). (4) ``{gamma} and fission-reactor radiation effects on the visible-range transparency of aluminum-jacketed, all-silica optical fibers,`` D.L. Griscom, J. Appl. Phys. 80, 2142-2155 (1996). (5) ``Visible/infra-red absorption study in fiber geometry of metastable defect states in high-purity fused silicas,`` D.L. Griscom, Proc. 13th Int`l Conf. on Defects in Insulating Materials, Wake Forest University, Winston-Salem, NC, July 1996. (6) ``Influence of the cladding thickness on the evolution of the NBOHC band in optical fibers exposed to gamma radiations,`` O. Deparis, D.L. Griscom, P. Megret, M. Decreton, and M. Blondel, J. Non-Cryst. Solids 216, 124-128 …
Date: August 22, 1998
Creator: Griscom, D.L.
Object Type: Report
System: The UNT Digital Library
Superconductivity in Strong Magnetic Field (Greater Than Upper Critical Field) (open access)

Superconductivity in Strong Magnetic Field (Greater Than Upper Critical Field)

The National High Magnetic Field Laboratory, funded by the National Science Foundation and other US federal Agencies, has in recent years built a wide range of magnetic fields, DC 25 to 35 Tesla, short pulse 50 - 60 Tesla, and quasi-continuous 60 Tesla. Future plans are to push the frontiers to 45 Tesla DC and 70 to 100 Tesla pulse. This user facility, is open for national and international users, and creates an excellent tool for materials research (metals, semiconductors, superconductors, biological systems ..., etc). Here we present results of a systematic study of the upper critical field of a novel superconducting material which is considered a promising candidate for the search for superconductivity beyond H{sub c2} as proposed by several new theories. These theories predict that superconductors with low carrier density can reenter the superconducting phase beyond the conventional upper critical field H{sub c2}. This negates the conventional thinking that superconductivity and magnetic fields are antagonistic.
Date: August 22, 1998
Creator: Tessema, G. X.; Gamble, B. K.; Skove, M. J.; Lacerda, A. H. & Mielke, C. H.
Object Type: Article
System: The UNT Digital Library
Computational Quantum Chemistry [Website] (open access)

Computational Quantum Chemistry [Website]

This report contains the contents of a web page related to research on the development of quantum chemistry methods for computational thermochemistry and the application of quantum chemistry methods to problems in material chemistry and chemical sciences. Research programs highlighted include: Gaussian-2 theory; Density functional theory; Molecular sieve materials; Diamond thin-film growth from buckyball precursors; Electronic structure calculations on lithium polymer electrolytes; Long-distance electronic coupling in donor/acceptor molecules; and Computational studies of NOx reactions in radioactive waste storage.
Date: August 22, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Countries of the World and International Organizations: Sources of Information (open access)

Countries of the World and International Organizations: Sources of Information

This report provides a selection of materials for locating information on foreign countries and international organizations. In the general information section, it presents sources giving an overview of politics, economics, and recent history. A specialized information section cites sources on human rights, immigration, international organizations, military strengths, terrorism, and other topics. Included are titles of some of the most frequently consulted bibliographic sources that are available for use in many libraries. Electronic information on foreign countries is also provided, via the Internet, by agencies of the federal government, international organizations, and related sources. Included is a list of foreign chanceries located in Washington, D.C.
Date: August 22, 1997
Creator: Salazar, Barbara A.
Object Type: Report
System: The UNT Digital Library
The integrated water conservation program at Sandia National Laboratories (open access)

The integrated water conservation program at Sandia National Laboratories

Sandia National Laboratories (SNL), located on Kirkland Air Force Base (KAFB) in Albuquerque, NM, is implementing a comprehensive water conservation program. Because the average rainfall in this metropolitan area of 500,000 is approximately 8 inches per year, conservation of this precious resource is critical to the economic health of the city and state, and the continued operations at SNL/NM. To address this need, SNL/NM is taking a systematic, comprehensive approach to water conservation. The approach is to estimate the water consumption for all of SNL/NM by type of consumption. For each type of water consumption, all cost effective measures for reducing, reclaiming, and/or recycling that usage will be ranked. These water conservation measures range from the simple such as retrofitting plumbing fixtures with low cost devices to reduce water required to flush toilets to the very complex. As an example of the very complex, a Microelectronics Development Laboratory (MDL) lab will implement a near zero water discharge from clean room wet benches. Deionized (DI) water can be sent back to the DI water input generation stream when the DI water is not being used for rinsing wafers. This paper discusses completed, ongoing and proposed projects at SNL/NM to reduce water …
Date: August 22, 1997
Creator: Rogers, D.
Object Type: Article
System: The UNT Digital Library
Pollution prevention/waste minimization program 1998 fiscal year work plan - WBS 1.11.2.1 (open access)

Pollution prevention/waste minimization program 1998 fiscal year work plan - WBS 1.11.2.1

Pollution Prevention/Waste Minimization (P2/WMin) is the Department of Energy`s preferred approach to environmental management. The P2/WMin mission is to eliminate or minimize waste generation, pollutant releases to the environment, use of toxic substances, and to conserve resources by implementing cost-effective pollution prevention technologies, practices, and polices.
Date: August 22, 1997
Creator: Howald, S. C.
Object Type: Report
System: The UNT Digital Library
Supporting documentation for the 1997 revision to the DOE Insulation Fact Sheet (open access)

Supporting documentation for the 1997 revision to the DOE Insulation Fact Sheet

The Department of Energy (DOE) Insulation Fact Sheet has been revised to reflect developments in energy conservation technology and the insulation market. A nationwide insulation cost survey was made by polling insulation contractors and builders, and the results are reported here. These costs, along with regional weather data, regional fuel costs, and fuel-specific system efficiencies were used to produce recommended insulation levels for new and existing houses. This report contains all of the methodology, algorithms, assumptions, references, and data resources that were used to produce the 1997 DOE Insulation Fact Sheet.
Date: August 22, 1997
Creator: Stovall, T.K.
Object Type: Report
System: The UNT Digital Library
Tank characterization report for double-shell tank 241-AN-103 (open access)

Tank characterization report for double-shell tank 241-AN-103

This document summarizes the information on the historical uses, present status, and the sampling and analysis results of waste stored in Tank 241-AN-103. This report supports the requirements of the Tri-Party Agreement Milestone M-44-10. (This tank has been designated an Hydrogen Watch List tank.)
Date: August 22, 1997
Creator: Wilkins, N.E.
Object Type: Report
System: The UNT Digital Library
Tank characterization report for single-shell tank 241-BY-112 (open access)

Tank characterization report for single-shell tank 241-BY-112

This document summarizes the information on the historical uses, present status, and the sampling and analysis results of waste stored in Tank 241-BY-112. This report supports the requirements of the Tri-Party Agreement Milestone M-44-10. (This tank has been designated a Ferrocyanide Watch List tank.)
Date: August 22, 1997
Creator: Baldwin, J.H.
Object Type: Report
System: The UNT Digital Library
Texas Register, Volume 22, Number 63, Pages 8321-8456, August 22, 1997 (open access)

Texas Register, Volume 22, Number 63, Pages 8321-8456, August 22, 1997

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.
Date: August 22, 1997
Creator: Texas. Secretary of State.
Object Type: Journal/Magazine/Newsletter
System: The Portal to Texas History
W-026, operational test report isokenetic stack effluent monitoring system (open access)

W-026, operational test report isokenetic stack effluent monitoring system

This Operational Test Report was performed to assure the Isokinetic Stack Effluent Monitoring System (ISEMS) operates in accordance with system design and specifications.
Date: August 22, 1997
Creator: Bottenus, R.J.
Object Type: Report
System: The UNT Digital Library
Waste management plan for the APT (open access)

Waste management plan for the APT

This revision of the APT Waste Management Plan details the waste management requirements and issues specific to the APT plant for design considerations, construction, and operation. The APT Waste Management Plan is by its nature a living document and will be reviewed at least annually and revised as required.
Date: August 22, 1997
Creator: England, J. L.
Object Type: Report
System: The UNT Digital Library
Geophysical investigation of the 216-U-1/2 pipeline, 200 west area (open access)

Geophysical investigation of the 216-U-1/2 pipeline, 200 west area

Ground-penetrating radar was used at three locations in an attempt to locate and determine the depth of the 216-U-1/2 pipeline. Many anomalies were found, all very useful to the project, but only some of which were identified with the pipeline.
Date: August 22, 1996
Creator: Fassett, J.W & Bergstrom, K.A., Westinghouse Hanford
Object Type: Report
System: The UNT Digital Library
Improvement of storage, handling, and transportability of fine coal. Quarterly technical progress report No. 6, April 1, 1995--June 30, 1995 (open access)

Improvement of storage, handling, and transportability of fine coal. Quarterly technical progress report No. 6, April 1, 1995--June 30, 1995

The major activities of the period were production operations of the demonstration circuit at Drummond`s Chetopa Preparation Plant near Graysville, Alabama. As the shakedown runs had shown, excellent quality Mulled Coal could be produced, and a total of 870 tonnes (966 tons) was produced. Quality was consistently better than the acceptable level. Immediately following the completion of the production demonstration, removal of equipment and decommissioning of the demonstration facility was undertaken and completed.
Date: August 22, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Improvement of storage, handling, and transportability of fine coal. Quarterly technical progress report No. 7, July 1, 1995--September 30, 1995 (open access)

Improvement of storage, handling, and transportability of fine coal. Quarterly technical progress report No. 7, July 1, 1995--September 30, 1995

The Mulled Coal process was developed as a means of overcoming the adverse handling characteristics of wet fine coal without thermal drying. The process involves the addition of a low cost harmless reagent to wet fine coal using off-the-shelf mixing equipment. Based on laboratory- and bench-scale testing, Mulled Coal can be stored, shipped, and burned without causing any of the plugging, pasting, carryback and freezing problems normally associated with wet coal. The objectives of this project are to demonstrate that: The Mulled Coal process, which has been proven to work on a wide range of wet fine coals at bench scale, will work equally well in a commercial coal preparation plant. The wet product from a fine coal cleaning circuit can be converted to a solid fuel form for ease of handling and cost savings in storage and rail car transportation. A wet fine coal product thus converted to a solid fuel form can be stored, shipped, and burned with conventional fuel handling, transportation, and combustion systems. The Mulled Coal circuit was installed in an empty bay at the Chetopa Preparation Plant. Equipment has been installed to divert a 2.7 tonnes/hr (3 tons/hr) slipstream of the froth concentrate to a …
Date: August 22, 1996
Creator: unknown
Object Type: Report
System: The UNT Digital Library
National Ignition Facility subsystem design requirements optics assembly building (OAB) SSDR 1.2.2.3 (open access)

National Ignition Facility subsystem design requirements optics assembly building (OAB) SSDR 1.2.2.3

This Subsystem Design Requirement (SSDR) document establishes the performance, design, and verification requirements `for the conventional building systems and subsystems of the Optics Assembly Building (OAB). These building system requirements are associated with housing and supporting the operational flow of personnel and materials throughout the OAB for preparing and repairing optical and mechanical components used in the National Ignition Facility (NIF) Laser and Target Building (LTAB). This SSDR addresses the following subsystems associated with the OAB: * Structural systems for the building spaces and operational-support equipment and building- support equipment. * Architectural building features associated with housing the space, operational cleanliness, and functional operation of the facility. * Heating, Ventilating, and Air Conditioning (HVAC) systems for maintaining a clean and thermally stable ambient environment within the facility. * Plumbing systems that provide potable water and sanitary facilities for the occupants and stormwater drainage for transporting rainwater. * Fire Protection systems that guard against fire damage to the facility and its contents. * Material handling equipment for transferring optical assemblies and other materials within building areas and to the LTAB. * Mechanical process piping systems for liquids and gases that provide cooling, cleaning, and other service to optical and mechanical components. …
Date: August 22, 1996
Creator: Kempel, P. & Hands, J.
Object Type: Report
System: The UNT Digital Library
Tank characterization report for double-shell tank 241-AN-106 (open access)

Tank characterization report for double-shell tank 241-AN-106

This document summarizes the information on the historical uses, present status, and the sampling and analysis results of waste store in Tank 241-AN-106. This report supports the requirements of Tri- Party Agreement Milestone M-44-09.
Date: August 22, 1996
Creator: Douglas, J.G., Westinghouse Hanford
Object Type: Report
System: The UNT Digital Library
Enigmatic electrons, photons, and ``empty`` waves (open access)

Enigmatic electrons, photons, and ``empty`` waves

A spectroscopic analysis is made of electrons and photons from the standpoint of physical realism. In this conceptual framework, moving particles are portrayed as localized entities which are surrounded by ``empty`` waves. A spectroscopic model for the electron Stands as a guide for a somewhat similar, but in essential respects radically different, model for the photon. This leads in turn to a model for the ``zeron``. the quantum of the empty wave. The properties of these quanta mandate new basis states, and hence an extension of our customary framework for dealing with them. The zeron wave field of a photon differs in one important respect from the standard formalism for an electromagnetic wave. The vacuum state emerges as more than just a passive bystander. Its polarization properties provide wave stabilization, particle probability distributions, and orbit quantization. Questions with regard to special relativity are discussed.
Date: August 22, 1995
Creator: MacGregor, M.H.
Object Type: Article
System: The UNT Digital Library
Improved Calibration Facility (open access)

Improved Calibration Facility

Aid in redesign of the calibration facility in order to: 1. Reduce the rate of exposure for calibration personnel below 1 mr/hr; 2. Reduce the rate of exposure outside of the 3745 Building; 3. Reduce the risk of breaking radium sources; 4. Improve the efficiency of calibration procedures by: a. Allowing calibration to be done faster; b. Providing several calibration ranges which can operate simultaneously in the present space allowed; c. Allowing instrument survey work to proceed while calibration work is done. A well-type calibration installation is proposed and a brief description of the required shielding is included.
Date: August 22, 1995
Creator: Roesch, W. C.
Object Type: Report
System: The UNT Digital Library