Article on polycyclic aromatic hydrocarbon solute probes and the evaluation of select hydrogenated pyrene, benzo[ghi]perylene, and naphthacene derivatives as possible solvent polarity probes.

Article on the solubility of anthracene in binary alkane + 1-propanol and alkane + 1-butanol solvent mixtures.

Article on the solubility of pyrene in binary alkane + 1-propanol and alkane + 2-propanol solvent mixtures.

Human Instrusion into the potential repository at Yucca Mountain, Nevada, was modeled in the Total-System Performance Assessment (``TSPA-91``) recently completed for the Yucca Mountain Site Characterization Project Office of the DOE. The scenario model assumed that the repository would be penetrated at random locations by a number of boreholes drilled using twentieth-century rotary drilling techniques.

Zeolitic rocks play an important role in retarding the migration of radionuclides that occur in solution as simple cations (Cs, Sr, Ba). However, the interaction of zeolites with complex transuranic species in solution provides little if any advantage over other common silicate minerals. The most important consequences of zeolite occurrences near a high-level radioactive waste repository environment are likely to be their response to thermal loading and their impact on site hydrology. Partial zeolite dehydration during the early thermal pulse from the repository and rehydration as the repository slowly cools can have an important impact on the water budget of a repository in unsaturated rocks, provided that the long-term heating does not result in zeolite destabilization.

Zeolites are abundant in the geologic record in both continental and marine environments. The purpose of the present study is to evaluate the utility of K-bearing zeolites for dating by the K/Ar method to determine the time of zeolite diagenesis at Yucca Mountain, Nevada (Fig. 1). At Yucca Mountain, K-rich clinoptilolite and possibly mordenite are the only potentially K/Ar dateable secondary minerals present in the zeolite-rich tuffs except for some illite/smectites ({ge}10% illite layers) associated with these minerals. Direct dating of K-rich clinoptilolite, the most abundant zeolite in the altered tuffs, is important to delineate zeolite chronology as part of the site characterization of Yucca Mountain.

The available momentum space of a FODO lattice is determined by the maximum value of the dispersion function ({delta}x = D{sub x} {partial_derivative}p/p). In a regular FODO lattice the dispersion function oscillates between its maximum and minimum values, which are always positive. The maximum value of the dispersion function in a FODO cell of a fixed length depends on the cell phase difference. An example of a new lattice, in which the dispersion function is lowered to half its value in the same FODO cell, is presented. ne available momentum space in the new lattice is raised to twice that in the FODO lattice by allowing the dispersion function to oscillate between the same positive and negative values. The maxima of the dispersion function in the new lattice have half the value of those within the regular 900 cells.

Under certain accident conditions, waste tanks in the In-Tank Processing (ITP) facility may contain significant concentrations of benzene and hydrogen. Because these gases are flammable, a safety analysis was required to demonstrate that the risk posed by the possible combustion of these gases is acceptable. In support of this analysis, the MELCOR/SR computer code was modified to simulate the combustion of benzene-hydrogen mixtures. MELCOR/SR was developed originally to analyze severe accidents that may occur in the SRS production reactors but many of its modules can be used also for non-reactor applications such as combustion and aerosol and radionuclide transport. The MELCOR/SR combustion model (package) was originally configured for the deflagration analysis of hydrogen-carbon monoxide mixtures. With minor changes to the coding in the combustion package subroutines, and the addition of benzene thermodynamic and transport properties to the input decks, MELCOR/SR was modified to analyze deflagrations in benzene-hydrogen gas mixtures. A MELCOR/SR model was created consisting of two control volumes connected by flow paths. One volume represents a type III waste tank; the other, the environment. The flow paths represent vents that open during the deflagration. Choked flow and radiative heat transfer from the hot gas to the cooling coils and …

The National Regulatory Research Institute (NRRI), with funding from the US Environmental Protection Agency (EPA) and the US Department of Energy (DOE), conducted four regional workshops` on state public utility commission implementation of the Clean Air Act Amendments of 1990 (CAAA). The workshops had four objectives: (1) to discuss key issues and concerns on CAAA implementation, (2) to encourage a discussion among states on issues of common interests, (3) to attempt to reach consensus, where possible, on key issues, and (4) to provide the workshop participants with information and materials to assist in developing state rules, orders, and procedures. From the federal perspective, a primary goal was to ensure that workshop participants return to their states with a comprehensive background and understanding of how state commission actions may affect implementation of the CAAA and to be able to provide guidance to their jurisdictional utilities. It was hoped that this would reduce some of the uncertainty utilities face and assist in the development of an efficient allowance market. This report is divided into two main sections. In Section II, eleven principal issues are identified and discussed. These issues were chosen because they were either the most frequently discussed or they were …

Using scanning tunneling microscopy, we have identified and characterized Si donors (Si{sub Ga}) in GaAs located on the (110) surface and in subsurface layers. Si{sub Ga} on the surface shows localized features with characteristic structures in good agreement with a recent theoretical calculation. Si{sub Ga} in subsurface layers appears as delocalized protrusions superimposed on the background lattice, which are interpreted in terms of the modification of the tunneling due to the tip-induced band bending perturbed by the Si{sub Ga} Coulomb potential.

Using the one-dimensional, time-independent conduction state, a constant of thermal heating conduction is given that brings about the known stabilization theorem and a closed expression for the bus bar to be cryogenically stable in superconducting accelerators.

This paper describes the response of the eddy current and quench loads on a proposed Superconducting SuperCollider 4-K liner system. The liner within a bore tube is designed to remove the radiated power and the photodesorbed gas that impair the beam tube vacuum. The bimetallic liner tube is subjected to cooldown and eddy current loads. The square liner tube is a two-shell laminated Nitronic-40 steel is used for strength and a copper inner layer for low impedance to the image currents. Perforated holes are used to remove the photodesorbed gases for vacuum maintenance. The holes are located in a low-stress area of the liner. Rectangular holes in a four-pole symmetry pattern are required for beam dynamic stability. The liner is conductivity cooled by the round steel bore tube with a 2-mm wall. The copper layer must not be stressed over the yield strength limit because copper properties such as conductivity are known to change when the copper is stressed over yield strength. This analysis will address liner system response under thermal, eddy current, and vaporized liquid helium loads in a quenching dipole magnet.

The relaxation time of particle numbers in hot hadronic matter with vanishing baryon number are estimated using the ideal gas approximation and taking into account resonance decays and annihilation processes as the only sources of particle number fluctuations.Near the QCD critical temperature the longest relaxation times turn out to be of the order of 10 fm and grow roughly exponentially to become of the order of 10^3 fm at temperatures around 100 MeV.As a consequence of such long relaxation times, a clear departure from chemical equilibrium must be observed in the momentum distribution of secondary particles produced in high energy nuclear collisions.

The CEBAF five pass recirculating, superconducting linac, being developed as a high power electron source for nuclear physics, is also an ideal FEL driver.The 45 MeV front end linac is presently operational with a CW (low peak current) nuclear physics gun and has met all CEBAF performance specifications including low emittance and energy spread (< 1 * 10^-4). Progress will be reported in commissioning.This experience leads to predictions of excellent FEL performance.Initial designs reported last year have been advanced.Using the output of a high charge DC photoemission gun under development with a 6 cm period wiggler produces kilowatt output powers in the 3.6 to 17 micrometer range in the fundamental.Third harmonic operation extends IR performance down to 1.2 micrometer.Beam at energies up to 400 MeV from the first full CEBAF linac will interact in a similar but longer wiggler to yield kilowatt UV light production at wavelengths as short as 0.15 micrometers.Full power FEL

The stochastic characteristics of the turbulent inflow have been shown to be of major significance in the accumulation of fatigue in wind turbines. Because most of the wind turbine installations in the US have taken place in multi-turbine or wind farm configurations, the fatigue damage associated with the higher turbulence levels within such arrangements must be taken into account when making estimates of component service lifetimes. The simultaneous monitoring of two adjacent wind turbines over a wide range of turbulent inflow conditions has given the authors more confidence in describing the structural load distributions that can be expected in such an environment. The adjacent testing of the two turbines allowed the authors to postulate that observed similarities in the response dynamics and load distributions could be considered quasi-universal, while the dissimilarities could be considered to result from the differing design of the rotors. The format has also allowed them to begin to define appropriate statistical load distribution models for many of the critical components in which fatigue is a major driver of the design. In addition to the adjacent turbine measurements, they also briefly discuss load distributions measured on a teetered-hub turbine.

The recent publication of the Digital Elevation Model (DEM) database by the US Geological Survey (USGS) has provided a unique opportunity for the development of cost-effective wind energy prospecting technology. This database contains terrain elevation values on a Latitude-Longitude grid with a resolution of 3 arc-seconds (about 90 m) for the contiguous United States, Hawaii, and Puerto Rico. This database has been coupled with software that will produce shaded-relief maps on a laser printer in a format compatible with the state wind power maps in the US wind energy atlas. By providing a much higher resolution of the terrain features than was possible when the US atlas was prepared, these maps can be useful in general wind prospecting activities. As highly resolved as the 90-m DEM data seem to be when compared to the atlas grid, they still appear to be too coarse to resolve terrain features in the detail required for local wind flow characterization and wind plant layout. Gridded terrain data at about 10-m resolution are available from the USGS for some areas of the United States. In areas where these data are unavailable, they may be generated by digitizing and gridding the contours from a 1:24,000-scale USGS …

Using Fabry-Perot interferometry techniques, we have determined the early time rate of energy release from detonating PETN and TNT explosives filled with 5 to 20 wt % of either 5 {mu}m or 18 {mu}m spherical aluminum with the detonation products, and calculate the extent of reaction at 1--3 {mu}s after the detonation. All of the metal in PETN formulations filled with 5 wt % and 10 wt % of either 5 {mu}m or 18 {mu}m aluminum reacted within 1.5 {mu}s, resulting in an increase of 18--22% in energy compared to pure PETN. For TNT formulations, between 5 to 10 wt % aluminum reacts completely with the same timeframe. A reactive flow hydrodynamic code model based on the Zeldovich-von Neumann-Doring (ZND) description of the reaction zone and subsequent reaction product expansion (Taylor wave) is used to address the reaction rate of the aluminum particles with detonation product gases. The detonation product JWL equation of state is derived from that of pure PETN using a parametric normalization methodology.

The grout system dynamic computer simulation was created to allow investigation of the ability of the grouting system to meet established milestones, for various assumed system configurations and parameters. The simulation simulates the movement of tank waste through the system versus time, from initial storage tanks, through feed tanks and the grout plant, then finally to a grout vault. The simulation properly accounts for the following (1) time required to perform various actions or processes, (2) delays involved in gaining regulatory approval, (3) random system component failures, (4) limitations on equipment capacities, (5) available parallel components, and (6) different possible strategies for vault filling. The user is allowed to set a variety of system parameters for each simulation run. Currently, the output of a run primarily consists of a plot of projected grouting campaigns completed versus time, for comparison with milestones. Other outputs involving any model component can also be quickly created or deleted as desired. In particular, sensitivity runs where the effect of varying a model parameter (flow rates, delay times, number of feed tanks available, etc.) on the ability of the system to meet milestones can be made easily. The grout system simulation was implemented using the ITHINK* …

The international effort to develop and implement new research reactor fuels utilizing low-enriched uranium, instead of highly- enriched uranium, continues to make solid progress. This effort is the cornerstone of a widely shared policy aimed at reducing, and possibly eliminating, international traffic in highly-enriched uranium and the nuclear weapon proliferation concerns associated with this traffic. To foster direct communication and exchange of ideas among the specialists in this area, the Reduced Enrichment Research and Test Reactor (RERTR) Program, at Argonne National Laboratory, sponsored this meeting as the eleventh of a series which began 1978. Individual papers presented at the meeting have been cataloged separately.

An unrecrystallized structure is found to significantly improve the work hardening characteristics by lowering the work hardening rate during early stages of deformation. This is in contrast to a recrystallized structure, which requires a higher work hardening rate to accommodate the greater degree of multiple slip necessary to maintain strain compatibility between the more randomly oriented grains. The stronger texture associated with the unrecrystallized structure allows deformation to occur more efficiently. Addition of magnesium also improves work hardening by increasing overall level of the work hardening rate. The improved characteristics of the work hardening behavior result in a parallel increase in both the strength and ductility at cryogenic temperatures. These findings are positive since they suggest a method by which improvements in the work hardening behavior and subsequent mechanical properties may be obtained through practical modifications of the microstructure and composition.

Measures to reduce the use of fossil fuels, suppression of on-farm emissions of methane (CH{sub 4}) and nitrous oxide (N{sub 2}O), afforestation, and geoengineering ``fixes`` have been proposed to mitigate or eliminate greenhouse-forced climate change. These measures will impact agriculture and other sectors of the economy. this report discusses the above impacts.

The cost of thin superconducting solenoid magnets can be estimated if one knows the magnet stored energy, the magnetic field volume product or the overall mass of the superconducting coil and its cryostat. This report shows cost data collected since 1979 for large superconducting solenoid magnets used in high energy physics. These magnets are characterized in most cases by the use of indirect two phase helium cooling and a superconductor stabilizer of very pure aluminum. This correlation can be used for making a preliminary cost estimate of proposed one of a kind superconducting magnets. The magnet costs quoted include the power supply and quench protection system but the cost of the helium refrigerator and helium distribution system is not included in the estimated cost.

Photoelectron diffraction and photoelectron holography, a newly developed variant of it, can provide a rich range of information concerning surface structure. These methods are sensitive to atomic type, chemical state, and spin state. The theoretical prediction of diffraction patterns is also well developed at both the single scattering and multiple scattering levels, and quantitative fits of experiment to theory can lead to structures with accuracies in the {plus_minus}0.03 {Angstrom} range. Direct structural information can also be derived from forward scattering in scanned-angle measurements at higher energies, path length differences contained in scanned-energy data at lower energies, and holographic inversions of data sets spanning some region in angle and energy space. Diffraction can also affect average photoelectron emission depths. Circular dichroism in core-level emission can be fruitfully interpreted in terms of photoelectron diffraction theory, as can measurements with spin-resolved core-spectra, and studies of surface magnetic structures and phase transitions should be possible with these methods. Synchrotron radiation is a key element of fully utilizing these techniques.

A mechanically alloyed 15 vol % SiCp/IN9021 aluminum composite exhibited a maximum elongation of 610 % at a very high strain of 5 s{sup {minus}1} at 823 K. Nonetheless, the maximum elongation was obtained at a lower strain rate than that where the maximum m value (about 0.5) was obtained. This discrepancy between the optimum superplastic strain rate for the largest elongation and the strain rate for the maximum m value was believed to be associated with the cavitation behavior. Cavitation behavior of the SiCp/IN9021 aluminum composite was, therefore, carried out. It was found that cavities initiated at ends of particulate reinforcements and parallel to the applied stress direction within initial small strains, and their subsequent growth and coalescence invariably leads to premature failure. Experimental results indicated that cavity growth is plasticity controlled and can be described by a model proposed by Stowell.