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3-D subsurface modeling within the framework of an environmental restoration information system: Prototype results using earthvision (open access)

3-D subsurface modeling within the framework of an environmental restoration information system: Prototype results using earthvision

As a result of the DOE Oak Ridge Reservation (DOE-ORR) placement on the EPA Superfund National Priorities List in December of 1989, all remedial activities, including characterization, remedial alternatives selection, and implementation of remedial measures, must meet the combined requirements of RCRA, CERCLA, and NEPA. The Environmental Restoration Program, therefore, was established with the mission of eliminating or reducing to prescribed safe levels the risks to the environment or to human health and safety posed by inactive and surplus DOE-ORR managed sites and facilities that have been contaminated by radioactive and surplus DOE-ORR managed sites and facilities that have been contaminated by radioactive, hazardous, or mixed wastes. In accordance with an established Federal Facilities Agreement (FFA), waste sites and facilities across the DOE-ORR have been inventoried, prioritized, and are being systematically investigated and remediated under the direction of Environmental Restoration. EarthVision, a product of Dynamic Graphics, Inc., that provides three-dimensional (3-D) modeling and visualization, was exercised within the framework of an environmental restoration (ER) decision support system. The goal of the prototype was to investigate framework integration issues including compatibility and value to decision making. This paper describes the ER program, study site, and information system framework; selected EarthVision results …
Date: December 31, 1994
Creator: Goeltz, R. T. & Zondlo, T. F.
System: The UNT Digital Library
8. annual national conference of black physics students -- A summary report (open access)

8. annual national conference of black physics students -- A summary report

The primary goals of the conference were to: (1) Develop a peer/mentor network within the African-American physics community; (2) Inform African-American students in physics of the various academic and professional opportunities; and (3) Bring important academic, economic and political issues and developments in the field to the attention of the students. The conference program was designed to fulfill these goals and optimize the students` exposure to physics as a professional and its real-life applications in both industry and academia.
Date: December 31, 1994
Creator: Valk, H.S.
System: The UNT Digital Library
59. Cold Spring Harbor symposium on quantitative biology: Molecular genetics of cancer (open access)

59. Cold Spring Harbor symposium on quantitative biology: Molecular genetics of cancer

Investigation of the mechanistic aspects of cancer has its roots in the studies on tumor viruses and their effects on cell proliferation, function, and growth. This outstanding progress was well documented in previous Cold Spring Harbor Symposia on Quantitative Biology. In the early to mid 1980s, progress on the development of chromosome mapping strategies and the accumulation of DNA probes that identified polymorphisms, encouraged by the international Human Genome Project, enabled the identification of other genes that contributed to familial inheritance of high susceptibility to specific cancers. This approach was very successful and led to a degree of optimism that one aspect of cancer, the multistep genetic process from early neoplasia to metastatic tumors, was beginning to be understood. It therefore seemed appropriate that the 59th Symposium on Quantitative Biology focus attention on the Molecular Genetics of Cancer. The concept was to combine the exciting progress on the identification of new genetic alterations in human tumor cells with studies on the function of the cancer gene products and how they go awry in tumor cells.
Date: December 31, 1994
Creator: unknown
System: The UNT Digital Library
1994 Annual Conference Program: CIEE (open access)

1994 Annual Conference Program: CIEE

CIEE`s research has two primary goals. The first is to identify, develop, and demonstrate efficient end-use energy technologies and processes. The second is to improve the data and analytical tools related to the end use of energy. This document consists of papers presented on the topics of residential cooling systems, energy efficiency in commercial buildings, emissions from gas combustion systems, HVAC distribution systems, alternative transportation systems, and emission reduction strategies.
Date: December 31, 1994
Creator: unknown
System: The UNT Digital Library
1994 DOE Technical Standards Program Workshop: Proceedings (open access)

1994 DOE Technical Standards Program Workshop: Proceedings

The DOE Technical Standards Program has been structured to provide guidance and assistance for the development, adoption, and use of voluntary standards within the Department. OMB Circular A-119, ``Federal Participation in the Development and Use of Voluntary Standards`` establishes the policy to be followed in working with voluntary standards bodies, and in adopting and using voluntary standards whenever feasible. The DOE Technical Standards Program is consistent with this policy and is dedicated to the task of promoting its implementation. The theme of this year`s workshop is ``Standards Initiatives in Environmental Management fostering the development and use of industry standards for safe, environmentally responsible operations.`` The objective of the workshop is to increase the participant`s awareness of the standardization activities taking place nationally and internationally and the impact of these activities on their efforts, and to facilitate the exchange of experiences, processes, and tools for implementing the program. Workshop sessions will include presentations by industry and Government notables in the environment, safety, and health arena with ample opportunity for everyone to ask questions and share experiences. There will be a breakout session which will concentrate on resolution of issues arising from the implementation of the DOE Technical Standards Program and a …
Date: December 31, 1994
Creator: Spellman, D. J.
System: The UNT Digital Library
Abstracts of oral and poster sessions (open access)

Abstracts of oral and poster sessions

The climate model of the Goddard Institute for Space Studies (GISS GCM) has been used to project the influence of increasing concentrations of greenhouse gases on the future global climate. New parameterizations for the GISS GCM are being developed to improve its depiction of current climate scenarios and to make it more sensitive to the variability of external forcing mechanisms such as sea-surface temperatures (SST), atmospheric aerosols and constituent trace gases. The new moist convection scheme makes cumulus fluxes proportional to vertical thermal instability and computes convective-scale downdrafts whose effect is to prevent excessive drying of the boundary layer by compensating subsidence. The physically-based ground hydrology component improves the land surface sensible and latent heat calculations by explicitly considering transpiration, evaporation from intercepted precipitation, evaporation from bare soil, infiltration, soil water flow and runoff. The revised planetary boundary layer uses a more valid physical model than previously to obtain more realistic near-surface winds and energy budgets. Preliminary results with newer versions of the GCM include a better seasonal migration of the ITCZ and more realistic tropical winds. One of our approaches to model validation is the evaluation of runs forced by globally observed sea-surface temperatures. The presentation will show how …
Date: December 31, 1994
Creator: Druyan, L. M.
System: The UNT Digital Library
Accelerator-based systems for plutonium destruction and nuclear waste transmutation (open access)

Accelerator-based systems for plutonium destruction and nuclear waste transmutation

Accelerator-base systems are described that can eliminate long-lived nuclear materials. The impact of these systems on global issues relating to plutonium minimization and nuclear waste disposal can be significant. An overview of the components that comprise these systems is given, along with discussion of technology development status and needs. A technology development plan is presented with emphasis on first steps that would demonstrate technical performance.
Date: December 31, 1994
Creator: Arthur, E. D.
System: The UNT Digital Library
Accelerator developments since the ZGS by ZGS people (open access)

Accelerator developments since the ZGS by ZGS people

The ZGS was a facility, as well as an organization, where people got together to pursue a common goal of doing exciting science of the day. In this note, the authors describe notable events related to accelerators and accelerator people since the closing of the ZGS program some 15 years ago. Many of the same ZGS people have been carrying out the state-of-the art accelerator work around the Laboratory with the same dedication that characterized their work in the earlier days. First the authors describe how the activities were re-organized after the closing of the ZGS, the migration of people, and the organizational evolution since that time. Doing this shows the similarity between the birth of the ZGS and the birth of the Advanced Photon Source (APS). Then, some of the accelerator work by the former ZGS people are described. These include: (1) Intense Pulsed Neutron Source (IPNS), (2) GeV Electron Microtron (GEM), (3) Wake Field Accelerator Test Facility, (4) Advanced Photon Source, and (5) IPNS Upgrade.
Date: December 31, 1994
Creator: Cho, Y.
System: The UNT Digital Library
Acceptance criteria for interim dry storage of aluminum-clad fuels (open access)

Acceptance criteria for interim dry storage of aluminum-clad fuels

Direct repository disposal of foreign and domestic research reactor fuels owned by the United States Department of Energy is an alternative to reprocessing (together with vitrification of the high level waste and storage in an engineered barrier) for ultimate disposition. Neither the storage systems nor the requirements and specifications for acceptable forms for direct repository disposal have been developed; therefore, an interim storage strategy is needed to safely store these fuels. Dry storage (within identified limits) of the fuels received from wet-basin storage would avoid excessive degradation to assure post-storage handleability, a full range of ultimate disposal options, criticality safety, and provide for maintaining confinement by the fuel/clad system. Dry storage requirements and technologies for US commercial fuels, specifically zircaloy-clad fuels under inert cover gas, are well established. Dry storage requirements and technologies for a system with a design life of 40 years for dry storage of aluminum-clad foreign and domestic research reactor fuels are being developed by various groups within programs sponsored by the DOE.
Date: December 31, 1994
Creator: Sindelar, R. L.; Peacock, H. B. Jr.; Iyer, N. C. & Louthan, M. R. Jr.
System: The UNT Digital Library
Achieving increased spent fuel storage capacity at the High Flux Isotope Reactor (HFIR) (open access)

Achieving increased spent fuel storage capacity at the High Flux Isotope Reactor (HFIR)

The HFIR facility was originally designed to store approximately 25 spent cores, sufficient to allow for operational contingencies and for cooling prior to off-site shipment for reprocessing. The original capacity has now been increased to 60 positions, of which 53 are currently filled (September 1994). Additional spent cores are produced at a rate of about 10 or 11 per year. Continued HFIR operation, therefore, depends on a significant near-term expansion of the pool storage capacity, as well as on a future capability of reprocessing or other storage alternatives once the practical capacity of the pool is reached. To store the much larger inventory of spent fuel that may remain on-site under various future scenarios, the pool capacity is being increased in a phased manner through installation of a new multi-tier spent fuel rack design for higher density storage. A total of 143 positions was used for this paper as the maximum practical pool capacity without impacting operations; however, greater ultimate capacities were addressed in the supporting analyses and approval documents. This paper addresses issues related to the pool storage expansion including (1) seismic effects on the three-tier storage arrays, (2) thermal performance of the new arrays, (3) spent fuel cladding …
Date: December 31, 1994
Creator: Cook, D. H.; Chang, S. J.; Dabs, R. D.; Freels, J. D.; Morgan, K. A.; Rothrock, R. B. et al.
System: The UNT Digital Library
Activities of HPS standards committee in environmental remediation (open access)

Activities of HPS standards committee in environmental remediation

The Health Physics Society (HPS) develops American National Standards in the area of radiation protection using methods approved by the American National Standards Institute (ANSI). Two of its sections, Environmental Health Physics and Contamination Limits, have ongoing standards development which are important to some environmental remediation efforts. This paper describes the role of the HPS standards process and indicates particular standards under development which will be of interest to the reader. In addition, the authors solicit readers to participate in the voluntary standards process by either joining active working groups (WG) or suggesting appropriate and relevant topics which should be placed into the standards process.
Date: December 31, 1994
Creator: Stencel, J. R. & Chen, S. Y.
System: The UNT Digital Library
Adiabatic theory of Wannier threshold laws and ionization cross sections (open access)

Adiabatic theory of Wannier threshold laws and ionization cross sections

The Wannier threshold law for three-particle fragmentation is reviewed. By integrating the Schroedinger equation along a path where the reaction coordinate R is complex, anharmonic corrections to the simple power law are obtained. These corrections are found to be non-analytic in the energy E, in contrast to the expected analytic dependence upon E.
Date: December 31, 1994
Creator: Macek, J.H. & Ovchinnikov, S.Yu.
System: The UNT Digital Library
Advanced computational research in materials processing for design and manufacturing (open access)

Advanced computational research in materials processing for design and manufacturing

The computational requirements for design and manufacture of automotive components have seen dramatic increases for producing automobiles with three times the mileage. Automotive component design systems are becoming increasingly reliant on structural analysis requiring both overall larger analysis and more complex analyses, more three-dimensional analyses, larger model sizes, and routine consideration of transient and non-linear effects. Such analyses must be performed rapidly to minimize delays in the design and development process, which drives the need for parallel computing. This paper briefly describes advanced computational research in superplastic forming and automotive crash worthiness.
Date: December 31, 1994
Creator: Zacharia, T.
System: The UNT Digital Library
Advanced manufacturing by spray forming: Aluminum strip and microelectromechanical systems (open access)

Advanced manufacturing by spray forming: Aluminum strip and microelectromechanical systems

Spray forming is an advanced materials processing technology that converts a bulk liquid metal to a near-net-shape solid by depositing atomized droplets onto a suitably shaped substrate. By combining rapid solidification processing with product shape control, spray forming can reduce manufacturing costs while improving product quality. INEL is developing a unique spray-forming method based on de Laval (converging/diverging) nozzle designs to produce near-net-shape solids and coatings of metals, polymers, and composite materials. Properties of the spray-formed material are tailored by controlling the characteristics of the spray plume and substrate. Two examples are described: high-volume production of aluminum alloy strip, and the replication of micron-scale features in micropatterned polymers during the production of microelectromechanical systems.
Date: December 31, 1994
Creator: McHugh, K.M.
System: The UNT Digital Library
Advanced Neutron Source Enrichment Study (open access)

Advanced Neutron Source Enrichment Study

A study has been performed of the impact on performance of using low enriched uranium (20% {sup 235}U) or medium enriched uranium (35% {sup 235}U) as an alternative fuel for the Advanced Neutron Source, which is currently designed to use uranium enriched to 93% {sup 235}U. Higher fuel densities and larger volume cores were evaluated at the lower enrichments in terms of impact on neutron flux, safety, safeguards, technical feasibility, and cost. The feasibility of fabricating uranium silicide fuel at increasing material density was specifically addressed by a panel of international experts on research reactor fuels. The most viable alternative designs for the reactor at lower enrichments were identified and discussed. Several sensitivity analyses were performed to gain an understanding of the performance of the reactor at parametric values of power, fuel density, core volume, and enrichment that were interpolations between the boundary values imposed on the study or extrapolations from known technology.
Date: December 31, 1994
Creator: Bari, R. A.; Ludewig, H. & Weeks, J. R.
System: The UNT Digital Library
Advanced tokamak operating modes in TPX and ITER (open access)

Advanced tokamak operating modes in TPX and ITER

A program is described to develop the advanced tokamak physics required for an economic steady-state fusion reactor on existing (short-pulse) tokamak experiments; to extend these operating modes to long-pulse on TPX; and finally to demonstrate them in a long-pulse D-T plasma on ITER.
Date: December 31, 1994
Creator: Nevins, W. M.
System: The UNT Digital Library
Advances in research for solid oxide fuel cells (open access)

Advances in research for solid oxide fuel cells

Solid oxide fuel cells are attracting considerable interest among industrial organizations wanting to position themselves in a potentially important technology of the future. More than a dozen new organizations worldwide have begun SOFC development in the last few years. Most of this R and D activity is in the planar technology, because it represents a good compromise between the proven but IR-limited tubular configuration and the high-performance but difficult-to-fabricate monolithic structure. The challenges of developing the planar cell configurations are finding high-temperature edge and manifold seal materials that will make very flat ceramic trilayers of sufficiently large area, and minimize contact resistances in stacks of cells. Also, decreasing the operating temperature requires development of reliable thin-film fabrication methods for the electrolyte, and finding a metal with good oxidation resistance and a thermal expansion coefficient well matched with the different cell components. Finally, toughness and a thermal stress tolerance of stacks need to be improved.
Date: December 31, 1994
Creator: Krumpelt, M.; Kueper, T. W. & Doshi, R.
System: The UNT Digital Library
Adventures in supercomputing: An innovative program for high school teachers (open access)

Adventures in supercomputing: An innovative program for high school teachers

Within the realm of education, seldom does an innovative program become available with the potential to change an educator`s teaching methodology. Adventures in Supercomputing (AiS), sponsored by the U.S. Department of Energy (DOE), is such a program. It is a program for high school teachers that changes the teacher paradigm from a teacher-directed approach of teaching to a student-centered approach. {open_quotes}A student-centered classroom offers better opportunities for development of internal motivation, planning skills, goal setting and perseverance than does the traditional teacher-directed mode{close_quotes}. Not only is the process of teaching changed, but the cross-curricula integration within the AiS materials is remarkable. Written from a teacher`s perspective, this paper will describe the AiS program and its effects on teachers and students, primarily at Wartburg Central High School, in Wartburg, Tennessee. The AiS program in Tennessee is sponsored by Oak Ridge National Laboratory (ORNL).
Date: December 31, 1994
Creator: Oliver, C. Edward; Hicks, H. Richard; Summers, Barbara G. & Staten, David G.
System: The UNT Digital Library
AEM investigation of tetrahedrally coordinated Ti{sup 4+} in nickel-titanate spinel (open access)

AEM investigation of tetrahedrally coordinated Ti{sup 4+} in nickel-titanate spinel

Stoichiometry and site distribution of metastable nickel-titanate spinel was studied with AEM. Results of EDXS and EELS agree that the metastable spinel is nonstoichiometric and titanium-deficient relative to its hypothetical endmember composition, ``Ni{sub 2}TiO{sub 4}``. The titanium deficiency has been determined by EELS to be {Delta} = 0.025 {plus_minus} 0.005. Channeling-enhanced microanalysis and ELNES studies indicate that the Ti{sup 4+} and Ni{sup 2+} cations are in tetrahedral and octahedral coordination, respectively, so that the metastable spinel has the normal cation distribution: Ti{sub l-{Delta}}[Ni{sub 2(1+{Delta})}]O{sub 4}. This is consistent with neutron powder-diffraction studies and SiO{sub 2}-solubility measurements of similar equilibrated and quenched spinel-containing specimens. Metastable nickel-titanate spinel therefore contrasts with stable stoichiometric spinels which tend to the inverse cation distribution, Me[MeTi]O{sub 4}.
Date: December 31, 1994
Creator: Anderson, I. M.; Bentley, J. & Carter, C. B.
System: The UNT Digital Library
Aging management of containment structures in nuclear power plants (open access)

Aging management of containment structures in nuclear power plants

Research is being conducted by ORNL under US Nuclear Regulatory Commission (USNRC) sponsorship to address aging management of nuclear power plant containment and other safety-related structures. Documentation is being prepared to provide the USNRC with potential structural safety issues and acceptance criteria for use in continued service evaluations of nuclear power plants. Accomplishments include development of a Structural Materials Information Center containing data and information on the time variation of 144 material properties under the influence of pertinent environmental stressors or aging factors, evaluation of models for potential concrete containment degradation factors, development of a procedure to identify critical structures and degradation factors important to aging management, evaluations of nondestructive evaluation techniques. assessments of European and North American repair practices for concrete, review of parameters affecting corrosion of metals embedded in concrete, and development of methodologies for making current condition assessments and service life predictions of new or existing reinforced concrete structures in nuclear power plants.
Date: December 31, 1994
Creator: Naus, D. J.; Oland, C. B.; Ellingwood, B. R.; Graves, H. L., III & Norris, W. E.
System: The UNT Digital Library
All wind farm uncertainty is not the same: The economics of common versus independent causes (open access)

All wind farm uncertainty is not the same: The economics of common versus independent causes

There is uncertainty in the performance of wind energy installations due to unknowns in the local wind environment, machine response to the environment, and the durability of materials. Some of the unknowns are inherently independent from machine to machine while other uncertainties are common to the entire fleet equally. The FAROW computer software for fatigue and reliability of wind turbines is used to calculate the probability of component failure due to a combination of all sources of uncertainty. Although the total probability of component failure due to all effects is sometimes interpreted as the percentage of components likely to fail, this perception is often far from correct. Different amounts of common versus independent uncertainty are reflected in economic risk due to either high probabilities that a small percentage of the fleet will experience problems or low probabilities that the entire fleet will have problems. The average, or expected cost is the same as would be calculated by combining all sources of uncertainty, but the risk to the fleet may be quite different in nature. Present values of replacement costs are compared for two examples reflecting different stages in the design and development process. Results emphasize that an engineering effort to …
Date: December 31, 1994
Creator: Veers, P.S.
System: The UNT Digital Library
Alternative catalyst and exhaust gas sensor work at Argonne National Laboratory (open access)

Alternative catalyst and exhaust gas sensor work at Argonne National Laboratory

Research programs at Argonne National Laboratory in the areas of automobile emissions monitoring and control are described. The mandate to improve automobile efficiency while reducing Pollution requires the development of new catalysts for exhaust emissions control that are capable of functioning efficiently under lean-burn engine operating conditions. It is also desirable that the use of expensive noble metal catalysts be avoided. NO{sub x} emissions will not be efficiently controlled by the current three-way, supported noble metal catalysts under lean-burn conditions. New catalysts are being sought that could effect the selective catalytic reduction (SCR) of NO{sub x} by exhaust hydrocarbons in the presence of oxygen. Molecular sieve zeolites of the ZSM-5 and ferrierite types, ion-exchanged with copper ions, are the best of the catalysts known to effect this chemistry, but the mechanism of the SCR is still not understood. In this project the authors will first undertake the investigation of the SCR of NO using model reactions to test postulated mechanistic pathways. Initial experiments have been devised to investigate the possible participation of metal alkyl complexes, metal oxime complexes, N-alkyl-N-nitroso-alkylaminato-metal complexes, and metal nitrile complexes in the zeolites. ANL will also develop microsensors, based on surface acoustic wave (SAW) chemical sensing …
Date: December 31, 1994
Creator: Iton, L. E.; Maroni, V. A.; Dieckman, S. L.; Sheen, S. H. & Raptis, A. C.
System: The UNT Digital Library
Ambient-pressure silica aerogel films (open access)

Ambient-pressure silica aerogel films

Very highly porous (aerogel) silica films with refractive index in the range 1.006--1.05 (equivalent porosity 98.5--88%) were prepared by an ambient-pressure process. It was shown earlier using in situ ellipsometric imaging that the high porosity of these films was mainly attributable to the dilation or `springback` of the film during the final stage of drying. This finding was irrefutably reconfirmed by visually observing a `springback` of >500% using environmental scanning electron microscopy (ESEM). Ellipsometry and ESEM also established the near cent per cent reversibility of aerogel film deformation during solvent intake and drying. Film thickness profile measurements (near the drying line) for the aerogel, xerogel and pure solvent cases are presented from imaging ellipsometry. The thickness of these films (crack-free) were controlled in the range 0.1-3.5 {mu}m independent of refractive index.
Date: December 31, 1994
Creator: Prakash, Sai S.; Brinker, C. Jeffrey & Hurd, Alan J.
System: The UNT Digital Library
American Nuclear Society 1994 student conference eastern region (open access)

American Nuclear Society 1994 student conference eastern region

This report contains abstracts from the 1994 American Nuclear Society Student Conference. The areas covered by these abstracts are: fusion and plasma physics; nuclear chemistry; radiation detection; reactor physics; thermal hydraulics; and corrosion science and waste issues.
Date: December 31, 1994
Creator: unknown
System: The UNT Digital Library