In this paper, we present a simple annealing procedure (which we refer to as ''flash-annealing'' because of short duration) that results in the formation of an ultralow friction surface film on vanadium diboride (VB{sub 2}) surfaces. This annealing is done in a box furnace at 800 C for a period of 5 min. During annealing, the exposed surface of the VB{sub 2} undergoes oxidation and forms a layer of boron oxide (B{sub 2}O{sub 3}). In open air, the B{sub 2}O{sub 3} layer reacts spontaneously with moisture and forms a boric acid (H{sub 3}BO{sub 3}) film. The friction coefficient of a 440C steel pin against this H{sub 3}BO{sub 3} film is {approx}0.05, compared to 0.8 against the as-received VB{sub 2}. Based on Raman spectroscopy and electron microscopy studies, we elucidate the ultralow friction mechanism of the flash-annealed VB{sub 2} surfaces.

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The new capacitive deionization system (CDI) removes ions, contaminants impurities from water and other aqueous process streams, and further selectively places the removed ions back into solution during regeneration. It provides a separation process that does not utilize chemical regeneration processes, and thus significantly reduces or completely eliminates secondary wastes associated with the operation of ion exchange resins. In the CDI, electrolyte flows in open channels formed between adjacent electrodes, and consequently the pressure drop is much lower than conventional separation processes. The fluid flow can be gravity fed through these open channels, and does not require membranes. This feature represents a significant advantage over the conventional reverse osmosis systems which include water permeable cellulose acetate membranes, and over the electrodialysis systems which require expensive and exotic ion exchange membranes. The CDI is adaptable for use in a wide variety of commercial applications, including domestic water softening, industrial water softening, waste water purification, sea water desalination, treatment of nuclear and aqueous wastes, treatment of boiler water in nuclear and fossil power plants, production of high-purity water for semiconductor processing, and removal of salt from water for agricultural irrigation. CDI accomplishes this removal of impurities by a variety of mechanisms, but …

The MACHO microlensing experiment's time-sampled photometry database contains blue and red lightcurves for nearly 9 million stars in the central bar region of the Large Magellanic Cloud (LMC). We have identified known LMC Planetary Nebulae (PN) in the database and find one, Jacoby 5, to be variable. We additionally present data on the ``parent populations`` of LMC PN, and discuss the star formation history of the LMC bar. 14 refs., 1 fig.

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The new method for HRA, ATHEANA, has been developed based on a study of the operating history of serious accidents and an understanding of the reasons why people make errors. Previous publications associated with the project have dealt with the theoretical framework under which errors occur and the retrospective analysis of operational events. This is the first attempt to use ATHEANA in a prospective way, to select and evaluate human errors within the PSA context.

The field of inorganic mass spectrometry has seen substantial change in the author`s professional lifetime (over 30 years). Techniques in their infancy 30 years ago have matured; some have almost disappeared. New and previously unthought of techniques have come into being; some of these, such as ICP-MS, are reasonably mature now, while others have some distance to go before they can be so considered. Most of these new areas provide fertile fields for researchers, both in the development of new analytical techniques and by allowing fundamental studies to be undertaken that were previously difficult, impossible, or completely unforeseen. As full coverage of the field is manifestly impossible within the framework of this paper, only those areas with which the author has personal contact will be discussed. Most of the work originated in his own laboratory, but that of other laboratories is covered where it seemed appropriate.

This paper describes the analytical process for the application of ATHEANA, a new approach to the performance of human reliability analysis as part of a PRA. This new method, unlike existing methods, is based upon an understanding of the reasons why people make errors, and was developed primarily to address the analysis of errors of commission.

This paper describes the knowledge base for the application of the new human reliability analysis (HRA) method, a ``A Technique for Human Error Analysis`` (ATHEANA). Since application of ATHEANA requires the identification of previously unmodeled human failure events, especially errors of commission, and associated error-forcing contexts (i.e., combinations of plant conditions and performance shaping factors), this knowledge base is an essential aid for the HRA analyst.

The Radiochemical Engineering Development Center (REDC) at ORNL has petitioned to establish a Californium-252 User Facility for Neutron Science for academic, industrial, and governmental researchers. The REDC Californium Facility (CF) stores the national inventory of sealed {sup 252}Cf neutron source for university and research loans. Within the CF, the {sup 252}Cf storage pool and two uncontaminated hot cells currently in service for the Californium Program will form the physical basis for the User Facility. Relevant applications include dosimetry and experiments for neutron tumor therapy; fast and thermal neutron activation analysis of materials; experimental configurations for prompt gamma neutron activation analysis; neutron shielding and material damage studies; and hardness testing of radiation detectors, cameras, and electronics. A formal User Facility simplifies working arrangements and agreements between US DOE facilities, academia, and commercial interests.

Studies of global change and other regional issues depend on ecological data collected at multiple study areas or sites. An information system model is proposed for compiling diverse data from dispersed sources so that the data are consistent, complete, and readily available. The model includes investigators who collect and analyze field measurements, science teams that synthesize data, a project information system that collates data, a data archive center that distributes data to secondary users, and a master data directory that provides broader searching opportunities. Special attention to format consistency is required, such as units of measure, spatial coordinates, dates, and notation for missing values. Often data may need to be enhanced by estimating missing values, aggregating to common temporal units, or adding other related data such as climatic and soils data. Full documentation, an efficient data distribution mechanism, and an equitable way to acknowledge the original source of data are also required.

In our recent x-ray photon correlation spectroscopy (speckle) experiments at NSLS, one of the challenges is to increase the coherent photon flux through a pinhole, whose size is chosen to match the beam`s horizontal transverse coherence length {ital l{sub h}}. We adopted an approach to vertically focus the x-ray beam so as to match its vertical transverse coherence length {ital l{sub v}}, (at NSLS X13, {ital l{sub v}}{approximately} 50{ital l{sub h}}, {ital l{sub h}}{approximately} 12 {mu}m at 3 KeV) with {ital l{sub h}}. By demagnifying the vertical size by a factor of {ital l{sub v}/l{sub h}}, we expect to increase the intensity of the x-rays through the pin hole by the same factor while keeping the beam coherent. A piece of commercial 3/8 inch thick float glass, by virtue of its low surface roughness ({approximately}3{Angstrom} rms), good reflectivity in the low photon energy range of interest and low cost, was chosen as the mirror material. A computer controlled motorized bender with a four point bending mechanism was designed and built to bend the float glass to a continuously variable radius of curvature from {approximately}700 m (intrinsic curvature of the glass surface) to < 300 m, measured with the Long Trace …

The Gershenson Radiation Oncology Center of Wayne State University (WSU), Detroit, Michigan, is using {sup 252}Cf medical sources for neutron brachytherapy. These sources are based on a 20-year-old design containing {le} 30 {micro}g {sup 252}Cf in the form of a cermet wire of Cf{sub 2}O{sub 3} in a palladium matrix. The Radiochemical Engineering Development Center (REDC) of Oak Ridge National Laboratory has been asked to develop tiny high-activity {sup 252}Cf neutron sources for use with remote afterloading equipment to reduce treatment times and dose to clinical personnel and to expedite treatment of brain and other tumors. To date, the REDC has demonstrated that {sup 252}Cf loadings can be greatly increased in cermet wires much smaller than before. Equipment designed for hot cell fabrication of these wires is being tested. A parallel program is under way to relicense the existing source design for fabrication at the REDC.

The objective of this project was to determine the savings in utility operating costs that could be obtained by installing a Battery Energy Storage System (BESS). The target utility was Kansas City Power and Light (KCPL), a typical Midwestern utility with a mix of generating plants and many interconnections. The following applications of battery energy storage were modeled using an Electric Power Research Institute (EPRI) developed and supported program called DYNASTORE: (1) Spinning Reserve Only (2) Load Leveling with Spinning Reserve (3) Load Leveling Only (4) Frequency Control DYNASTORE commits energy storage units along with generating units and calculates operating costs with and without energy storage, so that savings can be estimated. Typical weeks of hourly load data are used to make up a yearly load profile. For this study, the BESS power ranged from ``small`` to 300 MW (greater than the spinning reserve requirement). BESS storage time ranged from 1 to 8 hours duration (to cover the time-width of most peaks). Savings in operating costs were calculated for each of many sizes of MW capacity and duration. Graphs were plotted to enable the reader to readily see what size of BESS affords the greatest savings in operating costs.

Much attention is currently given to risk-based approaches to managing natural resources and hazardous waste. In order to apply a risk-based approach, input from the various stakeholders needs to be obtained early and updated throughout the effort. Applying a risk-based approach allows decisionmakers to evaluate options based upon sound scientific data. This paper discusses two examples of how risk-based approaches have been used to evaluate remediation options for management of natural resources and hazardous material problems in the Intermountain West. These examples demonstrate that without stakeholder involvement and using a risk-based approach, time and effort would have been wasted and decisions made to correct perceived rather than actual problems. The paper also describes the role that natural attenuation plays in making both risk and remedial action decisions.

It is common practice in applied mechanics to develop mathematical models for mechanical system behavior. Frequently, the actual physical system being modeled is also available for testing, and sometimes the test data are used to help identify the parameters of the mathematical model. However, no general-purpose technique exists for formally, statistically judging the quality of a model. This paper suggests a formal statistical procedure for the validation of mathematical models of physical systems when data taken during operation of the physical system are available. The statistical validation procedure is based on the bootstrap, and it seeks to build a framework where a statistical test of hypothesis can be run to determine whether or not a mathematical model is an acceptable model of a physical system with regard to user-specified measures of system behavior. The approach to model validation developed in this study uses experimental data to estimate the marginal and joint confidence intervals of statistics of interest of the physical system. These same measures of behavior are estimated for the mathematical model. The statistics of interest from the mathematical model are located relative to the confidence intervals for the statistics obtained from the experimental data. These relative locations are used …

This paper characterizes typical nonlinear loads into two types of harmonic sources -harmonic current source and harmonic voltage source, which produce highly distorted currents and voltages, respectively. The conventional approach of active harmonic compensation has been the parallel type or `shunt active filter.` It is shown in this paper that the shunt active filter is effective only to harmonic current sources but not to harmonic voltage sources. On the other hand, the active filter connected in series with the system or `series active filter` is very effective in suppression of the harmonic voltage sources. General compensation characteristics of shunt active filters and series active filters are given analytically. The features, required operation conditions, and application considerations of both filters are described analytically and demonstrated experimentally.

Spent nuclear fuel (SNF) can be treated in a molten salt electrorefiner for conversion into metal and mineral waste forms for geologic disposal. The fuel is dissolved in molten chloride salt. Non-transuranic fission products in the molten salt are ion-exchanged into zeolite A, which is subsequently mixed with glass and consolidated. Zeolite was found to be effective in removing fission product cations from the molten salt. Breakthrough of cesium and the alkaline earths occurred more rapidly than was observed for the rare earths. The effluent composition as a function of time is presented, as well as results for the distribution of fission products along the length of the column. Effects of temperature and salt flow rate are also discussed.

A new test simulation tool is being developed to support vibration test design and to evaluate the overall testability of a component or system. This environment, the Vibration Virtual Environment for Test Optimization (VETO), is utilized to optimally place vibration control and response transducers and to investigate the selection of test parameters needed in the design and performance of a vibration experiment. The engineer can investigate the effects of different control parameters prior to performing an actual vibration test. Additionally, new and existing fixture designs can be evaluated through the development of analytical or experimental models that can be integrated into the simulation environment. This test design environment also provides the engineer with the ability to combine analytically or experimentally derived models of the vibration test hardware, instrumentation and equipment into a simulation model that represents the vibration testing capability. Hardware-in-the-loop simulations can be conducted using this model to examine multiple facets of the test design. This paper presents a new tool that will assist test engineers in maximizing the value of vibration tests through the use of hardware-in-the-loop simulations.

The US DOE is endeavoring to clean up contamination created by the disposal of chemical and nuclear waste on the Oak Ridge Reservation (ORR), Tennessee, with an emphasis on minimizing off-site migration of contaminated surface and ground water. The task is complicated by inadequate disposal records and by the complexity of the local geology. Remote sensing data, including aerial photography and geophysics, have played an important role in the ORR site characterization. Are there advantages to collecting remote sensing data using Unmanned Aerial Vehicles (UAV`s)? In this paper, I will discuss the applications of UAV`s being explored at Oak Ridge National Laboratory (ORNL) under the sponsorship of the Department of Energy`s Office of Science and technology. These applications are : aerial photography, magnetic mapping, and Very Low Frequency (VLF) electromagnetic mapping.

We have made high-resolution neutron capture and transmission measurements on isotopically enriched samples of {sup 134}Ba and {sup 136}Ba at the Oak Ridge Electron Linear Accelerator (ORELA) in the energy range from 20 eV to 500 keV. Previous measurements had a lower energy limit of 3 - 5 keV, which is too high to determine accurately the Maxwellian-averaged capture cross section at the low temperatures (kT {approx} 6 - 12 keV) favored by the most recent stellar models of the {ital s}-process. Our results for the astrophysical reaction rates are in good agreement with the most recent previous measurement at the classical {ital s}-process temperature, kT = 30 keV, but show significant differences at lower 40 temperatures. We discuss the astrophysical implications of these differences.

ECF is a state of the art facility for design and testing of energetic materials and components. Two key elements are the flash x-ray machines: a 6-head 150 keV, and a 6-head 300-keV instrument. The 150 keV system was used to study the action and reaction of a linear shaped charge (LSC) while submerged in water; the submerged samples were viewed from the top to capture the interaction of one piece with another piece nearby. Each LSC was covered by separate rubber coverings and affixed to a composite plate. Three heads, delayed by a specified time, were used to capture the time sequence. Side views were done with and without the rubber coverings to examine the dampening effect of the cover. An end-on perspective was also captured by x-ray using one head and several time delays. Debris scatter from a larger device was also examined. Explosive used was in a pellet form initiated by a detonator and a timing lead. The x-ray radiographs show the particles from this device as they expand outward. Three x-ray source tubes were used in a large horizontal array, apertured to expose individual pieces of film. Another x-ray source was placed overhead and simultaneously exposed …

Measurements are reported of scattered neutral fractions for Na, K, Cs, and Ne singly and multicharged ions, and of scattered negative ion fractions for incident O, F, and B projectiles grazingly incident on LiF(100) as function of projectile velocity. In the case of the Na and Ne incident ions, significant dependence of the scattered neutral fractions on incident charge state is found, which is most pronounced at the lowest investigated velocities. Possible reasons for the observed initial charge state dependence are considered. In addition, results are reported for the target azimuthal dependence of the final neutral fraction observed for grazingly incident 35 keV Cs{sup +7} ions.

We have measured the transient reflectivity changes of bulk Ge after excitation with 140 fs laser pulses at 1.5 eV. The electron and hole carrier dynamics arc calculated using an ensemble Monte Carlo method. The observed reflectivity changes are due to three mechanisms: Diffusion, band gap renormalization, and carrier dynamics, particularly scattering of light holes to the heavy hole band via optical phonons.