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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 are shown and discussed. EarthVision proved effective in integrating complex data from disparate sources and in providing 3-D visualizations of the spatial relationships of the data, including contaminant plumes. Work is under way to expand the analysis to the full site, covering about 1600 acres, and to include data from new sources, particularly remote-sensing studies.
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.
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.
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.
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 plenary session to discuss the plans developed by the breakout groups. Many organizations provide services and products which support the development, processing, distribution, and retrieval of standards. Those organizations listed at the end of the agenda will have exhibits available for your perusal throughout the workshop. Last year`s workshop was very successful in stimulating an understanding of an interest in the standards program. This year, we hope to build on that success and provide an environment for the synergism of ideas to enhance the program and advance its implementation.
1994 New England Regional Science Bowl [held at] Massachusetts Institute of Technology, February 26, 1994
This report deals with the 1994 New England Regional Science Bowl, being held at the Massachusetts Institute of Technology.
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 model improvements increase the quality of simulated interannual variations in global circulation and tropical rainfall.
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.
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.
Accelerator Research Studies. Final Report, June 1, 1991--May 31, 1994
The Accelerator Research Studies program at the University of Maryland, sponsored by the Department of Energy is currently in the third year of its three-year funding cycle. The program consists of the following three tasks: Task A -- Study of the transport and longitudinal compression of intense, high-brightness beams; Task B -- Study of high-brightness beam generation in pseudospark devices; Task C -- Study of a gyroklystron high-power microwave source for linear colliders. The research for each task is detailed in this report.
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.
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 corrosion concerns related to the longer period of pool storage, and (4) impacts of increased spent fuel inventory on the pool water quality, water treatment systems, and LLLW volume.
Acoustically enhanced remediation of contaminated soil and ground water
This program systematically evaluates the use of acoustic excitation fields (AEFs) to increase fluid and contaminant extraction rates from a wide range of unconsolidated soils. Successful completion of this program will result in a commercially-viable, advanced in-situ remediation technology that will significantly reduce clean-up times and costs. This technology should have wide applicability since it is envisioned to augment existing remediation technologies, such as traditional pump and treat and soil vapor extraction, not replace them. The overall program has three phases: Phase 1--laboratory scale parametric investigation; Phase 2--technology scaling study; Phase 3--field demonstration. Phase 1 of the program, corresponding to this period of performance, has as its primary objectives to provide a laboratory-scale proof of concept, and to fully characterize the effects of AEFs on fluid and contaminant extraction rates in a wide variety of soil types. The laboratory measurements of the soil transport properties and process parameters will be used in a computer model of the enhanced remediation process. A Technology Merit and Trade Study will complete Phase 1.
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.
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.
Advanced characterization of forms of chlorine, organic sulfur, and trace elements in available coals from operating Illinois mines. [Quarterly] technical report, September 1--November 30, 1994
A set of 34 as-shipped coal samples from operating Illinois mines is available for this study to determine the forms of chlorine and sulfur and leachability of chlorine during wet grinding and froth flotation. The forms of chlorine may be inorganic, ionic, and organic. The forms of organic sulfur will include organic sulfide and thiophenic sulfur. Chlorine can be leached from coal during wet grinding. The potential for removal of chlorine from the samples during fine ({minus}200 mesh) and ultrafine ({minus}400 mesh) wet-grinding and during froth flotation designed primarily for removal of pyrite and ash will be determined. In addition, the organic/inorganic affinities of trace elements in as-shipped Illinois coals will be assessed so that the current physical coal cleaning results may be better interpreted.
Advanced coal liquefaction: Quarterly report, final, October 1, 1994--December 31, 1994
A carbon-coated membrane has been identified as an alternative to overcome the degradation of the solvent, tetralin, which resulted in plugging the porous structure of the membrane. In this quarter, the authors have established a carbon coating facility and performed a coating study. This quarterly report summarizes the results, describing the facility assembly, the operating conditions for carbon coating, and characterization before and after coating. Membranes are to be used for the upgrading study.
Advanced computational methods for nodal diffusion, Monte Carlo, and S{sub n} problems. Final Report
The work addresses basic computational difficulties that arise in the numerical simulation of neutral particle radiation transport: discretized radiation transport problems, iterative methods, selection of parameters, and extension of current algorithms.
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.
Advanced electrorefiner design
This invention relates to a process and apparatus for electrochemically refining spent nuclear fuel from a nuclear reactor and recovering purified uranium and a mixture of uranium and plutonium for use as fresh blanket and core fuel in a nuclear reactor. A combination anode and cathode is described for an electrorefiner which includes a hollow cathode and an anode positioned inside the hollow cathode such that a portion of the anode is near the cathode. A retaining member is positioned at the bottom of the cathode. Mechanism is included for providing relative movement between the anode and the cathode during deposition of metal on the inside surface of the cathode during operation of the electrorefiner to refine spent nuclear fuel. A method is also disclosed which includes electrical power means selectively connectable to the anode and the hollow cathode for providing electrical power to the cell components, electrically transferring uranium values and plutonium values from the anode to the electrolyte, and electrolytically depositing substantially pure uranium on the hollow cathode. Uranium and plutonium are deposited at a liquid cathode together after the PuCl{sub 3} to UCl{sub 3} ratio is greater than 2:1. Slots in the hollow cathode provides close anode access for the liquid pool in the liquid cathode.
Advanced liquefaction using coal swelling and catalyst dispersion techniques. Volume 1, Final technical report, October 1, 1991--September 30, 1994
The overall objective of this project was to develop a new approach for the direct liquefaction of coal to produce an all-distillate product slate at a sizable cost reduction over current technology. The approach integrated coal selection, pretreatment, coal swelling with catalyst impregnation, liquefaction, product recovery with characterization, alternate bottoms processing, and a technical assessment including an economic evaluation. Heterofunctional solvents were the most effective in swelling coals. Also solvent blends such as isopropanol/water were more effective than pure solvents alone. Impregnating slurry catalysts simultaneously during coal swelling showed that better uptake was achieved with nonswelling solvent and higher impregnation temperature. Some enhancement in initial coal conversion was seen liquefying SO{sub 2}-treated Black Thunder coal with slurry catalysts, and also when hydrogen donor liquefaction solvents were used. Noncatalytic reactions showed no benefit from SO{sub 2} treatment. Coupling coal swelling and SO{sub 2} treatment with slurry catalysts was also not beneficial, although high conversion was seen with continuous operation and long residence time, however, similar high conversion was observed with untreated coal. SO{sub 2} treatment is not economically attractive unless it provides about 17% increase in coal reactivity. In most cases, the best results were obtained when the coal was untreated and the slurry catalyst was added directly into the reactor. Foster Wheeler`s ASCOT process had better average liquid yields than either Wilsonville`s vacuum tower/ROSE combination or delayed coking process. This liquid product also had good quality.
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.
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.
Advanced Neutron Source enrichment study -- Volume 1: Main report. Final report, Revision 12/94
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. Volume 2 of this report contains 26 appendices containing results, meeting minutes, and fuel panel presentations.
Advanced Neutron Source enrichment study. Volume 2: Appendices -- Final report, Revision 12/94
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. Volume 2 of this report contains 26 appendices containing results, meeting minutes, and fuel panel presentations. There are 26 appendices in this volume.
Advanced technologies for decontamination and conversion of scrap metals
Recycle of radioactive scrap metals (RSM) from decommissioning of DOE uranium enrichment and nuclear weapons manufacturing facilities is mandatory to recapture the value of these metals and avoid the high cost of disposal by burial. The scrap metals conversion project detailed below focuses on the contaminated nickel associated with the gaseous diffusion plants. Stainless steel can be produced in MSC`s vacuum induction melting process (VIM) to the S30400 specification using nickel as an alloy constituent. Further the case alloy can be rolled in MSC`s rolling mill to the mechanical property specification for S30400 demonstrating the capability to manufacture the contaminated nickel into valuable end products at a facility licensed to handle radioactive materials. Bulk removal of Technetium from scrap nickel is theoretically possible in a reasonable length of time with the high calcium fluoride flux, however the need for the high temperature creates a practical problem due to flux volatility. Bulk decontamination is possible and perhaps more desirable if nickel is alloyed with copper to lower the melting point of the alloy allowing the use of the high calcium fluoride flux. Slag decontamination processes have been suggested which have been proven technically viable at the Colorado School of Mines.
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.
Advanced turbine systems (ATS) program conceptual design and product development. Quarterly report, September 1 - November 30, 1994
Achieving the advanced turbine system goals of 60% efficiency, 8 ppmvd NOx, and 10% electric power cost reduction imposes competing characteristics on the gas turbine system: the turbine inlet temperature must increase, although this will lead to increased NOx emission. Improved coating and materials along with creative combustor design can result in solutions. The program is focused on two specific products: a 70 MW class industrial gas turbine based on GE90 core technology utilizing an innovative air cooling methodology, and a 200 MW class utility gas turbine based on an advanced GE heavy duty machines utilizing advanced cooling and enhancement in component efficiency. This report reports on tasks 3-8 for the industrial ATS and the utility ATS. Some impingement heat transfer results are given.
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.
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).
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}.
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.
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 test and evaluate the design assumptions is necessary to advance a design from the high uncertainty of the conceptual stages to the lower uncertainty of a well engineered and tested machine.
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 techniques, and a micro mass-spectrometer (MS) for tailpipe or engine-out emission monitoring. The sensor configurations and sensing techniques of the proposed SAW and micro-MS are described.
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.
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.
Ames Laboratory site environmental report, Calendar year 1994
The Ames Laboratory conducts fundamental research in the physical, chemical, materials, and mathematical sciences and engineering which underlie energy generating, conversion, transmission and storage technologies, environmental improvement, and other technical areas essential to national needs. These efforts will be maintained so as to contribute to the achievement of the vision of DOE and, more specifically, to increase the general levels of knowledge and technical capabilities, to prepare engineering and physical sciences students for the future, both academia and industry, and to develop new technologies and practical applications from our basic scientific programs that will contribute to a strengthening of the US economy. The Laboratory approaches all its operations with the safety and health of all workers as a constant objective and with genuine concern for the environment. The Laboratory relies upon its strengths in materials synthesis and processing, materials reliability, chemical analysis, chemical sciences, photosynthesis, materials sciences, metallurgy, high-temperature superconductivity, and applied mathematical sciences to conduct the long term basic and intermediate range applied research needed to solve the complex problems encountered in energy production, and utilization as well as environmental restoration and waste management. Ames Laboratory will continue to maintain a very significant and highly beneficial pre-college math and science education program which currently serves both teachers and students at the middle school and high school levels. Our technology transfer program is aided by joint efforts with ISU`s technology development and commercialization enterprise and will sustain concerted efforts to implement Cooperative Research and Development Agreements, industrially sponsored Work for Others projects. and scientific personnel exchanges with our various customers.
Amorphization and the effect of implanted ions in SiC
The effects of implanted ion chemistry and displacement damage on the amorphization threshold dose of SiC were studied using cross-section transmission electron microscopy. Room temperature as well as 200 and 400 C irradiations were carried out with 3.6 MeV Fe, 1.8 MeV Cl, 1 MeV He or 0.56 MeV Si ions. The room temperature amorphization threshold dose in irradiated regions well separated from the implanted ions was found to range from 0.3 to 0.5 dpa for the four different ion species. The threshold dose for amorphization in the He, Si and Fe ion-implanted regions was also {approximately}0.3 to 0.5 dpa. On the other hand, the amorphization threshold in the Cl-implanted region was only about 0.1 dpa. The volume change associated with amorphization was {approximately}17%. No evidence for amorphization was obtained in specimens irradiated at 200 or 400 C. An understanding of the microstructural evolution of SiC under irradiation is critical to the application of these materials in fusion energy systems.
Analysis of the implications of the USSR providing reprocessing and MOX fabrication services to other countries
This brief analysis, which is based on unclassified sources, seeks to identify what some of the implications would be if the Soviets started to move actively to try to provide reprocessing and MOX fabrication services to the US and other countries. While information on Soviet intentions is limited, it postulates that the Soviets would offer to reprocess spent LWR at competitive prices, fabricate the plutonium and reenrich the uranium, and sell these products back to the customer. Since it is not known whether they would insist on returning the waste from reprocessing or would be prepared to keep it, we comment briefly on what the implications of either of these actions might be.
Analysis of the potential for new automotive uses of magnesium
This paper describes the scope of a new project, just initiated, for the Lightweight Materials Program within the Office of Transportation Materials. The Center for Transportation Research and the Energy Technology Division at Argonne National Laboratory will assess the feasibility and technical potential of using magnesium and its alloys in place of steel or aluminum for automotive structural and sheet applications in order to enable more energy-efficient, lightweight passenger vehicles. The analysis will provide an information base to help guide magnesium research and development in the most promising directions.
An analysis of the situation and current trends in the management of construction projects at Los Alamos National Laboratory
At Los Alamos National Laboratory (LANL) there is a more to switch from reliance on rules to an expanded reliance on market forces, as evidenced by the facilities recharge program. This paper moves beyond the market/rule debate to argue that new approaches to project management are required. Managers at all levels in the LANL face contending demands as they are caught between immediate concerns and long term consequences, keeping track of the big picture and looking after the details. Management techniques appropriate for simple certain projects will be of limited value on complex uncertain projects built on tight schedules--no matter how market and rules are balanced in the larger organization. Thus the degree of complexity, uncertainty, and duration, should shape the choice of project management approaches. Single dimension simple buzz word solutions will do little good and may cause harm. This report reviews current situation and efforts underway to improve performance are reviewed. These efforts are shown to be useful but incomplete as significant improvement will both require altering and expanding how managers and the management system respond to contending demands.
Analytical laboratory and mobile sampling platform. Progress report, October 1, 1994--December 31, 1994
This paper is a quarterly report describing the use of a new soil gas collection device which allows the collection of soil gas in the field for later analysis in the laboratory. It describes the installation of this sampling device and the procedure for setting the probe, extraction of soil gas beneath the surface, and sealing of the soil gas for transport. The sites used for initial testing was the top of Yucca Mountain and Crystal Spring in Ash Meadows National Wildlife Refuge. The results from this initial test showed no volatile matter present in the soil at these locations.
An analytical method of predicting Lee-Kesler-Ploecker binary interaction coefficients: Part 1, For non-polar hydrocarbon mixtures
An analytical method is proposed for finding numerical values of binary interaction coefficients for non-polar hydrocarbon mixtures when the Lee-Kesler (LK) equation of state is applied. The method is based on solving simultaneous equations, which are Ploecker`s mixing rules for pseudocritical parameters of a mixture, and the Lee-Kesler equation for the saturation line. For a hydrocarbon mixture, the method allows prediction of {kappa}{sub ij} interaction coefficients (ICs) which are close to values obtained by processing experimental p-v-t data on the saturation line and subsequent averaging. For mixtures of hydrocarbon molecules containing from 2 to 9 carbon atoms, the divergence between calculated and experimentally based ICs is no more than {plus_minus}0.4%. The possibility of extending application of this method to other non-polar substances is discussed.
Analyzing organic sulfur in coal/char: Integrated mild degradation/XANES methods. Final technical report, September 1, 1993--November 30, 1994
The overall goal of this study is to improve the understanding of sulfur in coals/chars via the use of combined advanced nondestructive and advanced destructive methods of sulfur analysis. This study combines selective oxidation, analytical pyrolysis, and sulfur X-ray Absorption Near Edge Structure Spectroscopy (XANES) analysis. Samples with a wide variety of sulfur contents, (0.63%--4.40%) have been prepared for use in this study. This includes steam gasification chars, oxidized coals and desulfurized coals as well of the original unaltered coals. Mild pyrolysis and XANES data shows that the sulfur chemistry of gasification chars is significantly different from that of the original coals. Mild pyrolysis of the samples that were oxidized with peroxyacetic acid showed that the level of simple thiophene structures observed in the pyrolysis products declines with increasing levels of oxidation. Sulfur XANES spectra of treated samples showed various effects depending on the treatment severity. The XANES spectra of less severely treated samples were similar, although not identical, to the untreated coal spectra. XANES of gasification chars indicated conversion of pyrite to pyrrhotite, removal of organic sulfide sulfur and dissolution of soluble inorganic sulfur species during gasification. Mild oxidation with peroxyacetic acid results in preferential oxidation of sulfide forms before thiophene forms but increasing oxidation severity leads to virtually all sulfur species being oxidized. Good agreement between W-band EPR and XANES data for aromatic sulfur contents were obtained. The TPR analysis of coal indicated that organic sulfur was present as alkyl-aryl sulfide, aryl-aryl sulfides, simple thiophenes and condensed thiophenes. TPR shows that non-thiophenic compounds are removed by PAA oxidation, and that the longer the oxidation is performed the greater is the removal of non-thiophenic sulfur structures.
Annual report on paleoclimate studies for the Yucca Mountain project site characterization conducted by the Desert Research Institute
The prospect that Yucca Mountain may become a repository for high-level radionuclides with especially long half-lives means that the intended waste containment area must be well beyond the reach of the hydrologic system for at least ten millennia. Through the integration of several avenues of paleoclimatic proxy data, the authors intend to arrive at definite conclusions regarding rates of change, and extremes and stabilities of past climate regimes. These will in turn lead to rough estimates of: the amounts of rainfall available for recharge during past periods of effectively wetter climate, and the durations and frequencies of recharge periods. The paper gives summaries of the following studies: Late Quaternary and Holocene climate derived from vegetation history and plant cellulose stable isotope records from the Great basin of western North America; Accomplishments of paleofaunal studies, 1993--1994; Geomorphology studies in the Great Basin; Alluvial fan response to climatic change, Buena Vista Valley, central Nevada; Sedimentology, stratigraphy, and chronology of lacustrine deposition in the Fernley Basin, west-central Nevada; Tree-rings, lake chronologies, alluvial sequences and climate--Implications for Great Basin paleoenvironmental studies; Stable isotopic validation studies--Fossil snails; and Late Pleistocene and Holocene eolian activity in the Mojave Desert.
Annual site environmental report for calendar year 1994
The Western Area Power Administration (Western) has established a formal environmental protection, auditing, monitoring, and planning program that has been in effect since 1978. The significant environmental projects and issues Western was involved with in 1994 are discussed in this annual site environmental report. It is written to show the nature and effectiveness of the environmental protection program. The Department of Energy order 5400.1, Chapter II.4, requires the preparation of an annual site environmental report. Because Western has facilities located in 15 states, this report addresses the environmental activities in all the facilities as one ``site.``
Annual site environmental report for calendar year 1994
The Western Area Power Administration (Western) has established a formal environmental protection, auditing, monitoring, and planning program that has been in effect since 1978. The significant environmental projects and issues Western was involved with in 1994 are discussed in this annual site environmental report. It is written to show the nature and effectiveness of the environmental protection program. The Department of Energy Order 5400.1, Chapter 2.4, requires the preparation of an annual site environmental report. Because Western has facilities located in 15 states, this report addresses the environmental activities in all the facilities as one ``site``. In 1994, Western provided power to more than 600 wholesale power customers consisting of cooperatives, municipalities, public utility districts, investor-owned utilities, federal and state agencies, irrigation districts, and project use customers. The wholesale power customers, in turn, provide service to millions of retail consumers in the States of California, Nevada, Montana, Arizona, Utah, New Mexico, Texas, North Dakota, South Dakota, Iowa, Colorado, Wyoming, Minnesota, Nebraska, and Kansas. Western is responsible for the operation and maintenance of nearly 17,000 miles of transmission lines, 271 substations, 55 hydroelectric power stations, and a coal-fired power plant.
Application of Latin hypercube sampling to RADTRAN 4 truck accident risk sensitivity analysis
The sensitivity of calculated dose estimates to various RADTRAN 4 inputs is an available output for incident-free analysis because the defining equations are linear and sensitivity to each variable can be calculated in closed mathematical form. However, the necessary linearity is not characteristic of the equations used in calculation of accident dose risk, making a similar tabulation of sensitivity for RADTRAN 4 accident analysis impossible. Therefore, a study of sensitivity of accident risk results to variation of input parameters was performed using representative routes, isotopic inventories, and packagings. It was determined that, of the approximately two dozen RADTRAN 4 input parameters pertinent to accident analysis, only a subset of five or six has significant influence on typical analyses or is subject to random uncertainties. These five or six variables were selected as candidates for Latin Hypercube Sampling applications. To make the effect of input uncertainties on calculated accident risk more explicit, distributions and limits were determined for two variables which had approximately proportional effects on calculated doses: Pasquill Category probability (PSPROB) and link population density (LPOPD). These distributions and limits were used as input parameters to Sandia`s Latin Hypercube Sampling code to generate 50 sets of RADTRAN 4 input parameters used together with point estimates of other necessary inputs to calculate 50 observations of estimated accident dose risk.Tabulations of the RADTRAN 4 accident risk input variables and their influence on output plus illustrative examples of the LHS calculations, for truck transport situations that are typical of past experience, will be presented .
An application of mechanical leverage to microactuation
Preliminary results on the use of mechanical advantage to convert a short-displacement, high-force actuation mechanism into a long-displacement, medium-force actuator are presented. This micromechanical, mechanically-advantaged actuator is capable of relatively large displacement and force values. The target design values are lever ration of 17.5:1 leading to a {plus_minus}17.5 {mu}N of force throughout providing no less than 2.25 {mu}N of force throughout actuator`s range of motion for an applied voltage of less tan 50 volts. The basis for the mechanical advantage is simple levers with fulcrums.
Applications of Langevin and Molecular Dynamics methods
Computer simulation of complex nonlinear and disordered phenomena from materials science is rapidly becoming an active and new area serving as guide for experiments and for testing of theoretical concepts. This is especially true when novel massively parallel computer systems and techniques are used on these problems. In particular the Langevin dynamics simulation technique has proven useful in situations where the time evolution of a system in contact with a heat bath is to be studied. The traditional way to study systems in contact with a heat bath has been via the Monte Carlo method. While this method has indeed been used successfully in many applications, it has difficulty addressing true dynamical questions. Large systems of coupled stochastic ODEs (or Langevin equations) are commonly the end result of a theoretical description of higher dimensional nonlinear systems in contact with a heat bath. The coupling is often local in nature, because it reflects local interactions formulated on a lattice, the lattice for example represents the underlying discreteness of a substrate of atoms or discrete k-values in Fourier space. The fundamental unit of parallelism thus has a direct analog in the physical system the authors are interested in. In these lecture notes the authors will illustrate the use of Langevin stochastic simulation techniques on a number of nonlinear problems from materials science and condensed matter physics that have attracted attention in recent years. First, the authors will review the idea behind the fluctuation-dissipation theorem which forms that basis for the numerical Langevin stochastic simulation scheme. The authors then show applications of the technique to various problems from condensed matter and materials science.
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