The goal of this investigation is to develop a description of the biaxial behavior of extruded powder aluminum at elevated temperature. Specimens made of extruded 101 ALCOA (Aluminum Company of America) powder aluminum and specimens made from 1100 commercial aluminum rod are tested biaxially in tension-torsion and compression-torsion loadings at the extrusion temperature. The powder aluminum is examined microscopically and stereological methods are used to give a quantified description of the material behavior in terms of changes in the laminar powder material structure. A model for the biaxial (tension-torsion) behavior of extruded powder aluminum is developed. This description is consistent with a previous analysis of behavior in pure tension.

It is argued that quantum measurements do pose a problem, within the context created by the fundamental aim of science, which is identified as the construction of a cohesive, comprehensive, and rationally coherent idea of the nature of the world in which we live. Models of nature are divided into two classes: (1), those in which there is a selection process that, for any possible measurement, would, if that measurement were to be performed, pick out one single outcome, and, (2), all others. It is proved that any model of class that reproduces the predictions of quantum theory must violate the condition that there be no faster-than-light influences of any kind. This result is used to motivate the study of models in which unitary evolution is maintained and there is no selection of unique outcomes. A consideration of ontic probabilities, historical records, and the form of the mind-brain connection leads to an elaboration of the Everett many-worlds interpretation that appears to provide the basis of satisfactory solution of the measurement problem. 18 refs.

An Electronic Speckle pattern interferometer (ESPI) was constructed which performs full-field surface displacement measurements. This measurement technique when combined with a single-point measurement known as laser vibrometry, can completely determine the vibrational characteristics of complex structures. This information can, in turn, be used for nondestructive testing as well as for modal analysis. One NDT E technique is to vibrationally excite the object and evaluate the time averaged interferograms from the ESPI and the vibration spectra from the vibrometer. Anomalies in the interferograms can be related to subsurface defects such as defective weld joints, internal cracks, voids, etc. All of this can be accomplished in a noncontacting and nonintrusive manor. In many instances, a finite element analysis in concert with this approach can be useful in interpreting the results. Since ESPI is analogous to optical holography, other methods equivalent to real-time and double-pulse holography may also be easily applied. As in holography, EXSPI is sensitive to out-of-plane surface displacements. Other optical arrangements can be implemented with the same equipment to give in-plane displacements which would give results similar to Moire interferometry without the need to apply gratings to the object under test. The advantage of this method over holographic interferometry is …

EMPACT is a high-transverse-momentum physics detector for the SSC. It aims for a precise measurement of electrons, muons, jets, and missing transverse energy using a superior calorimeter surrounded by air-core toroidal magnets forming a precision muon spectrometer. The baseline design of EMPACT is described. 5 refs., 11 figs.

The acceptable operating limits of a nuclear reactor are set to prevent fuel cladding damage. Critical Heat Flux (CHF) is the limiting criterion for the high pressure systems such as the BWRs (6.9 MPa) and the PWRs (13.8 MPa). However, the Onset of Flow Instability (OFI) is the limiting criterion of the low pressure system such as the existing Savannah River Site (SRS) production reactors (0.2 MPa). The physical basis of this difference is presented. 3 refs.

The radioactive waste glass melter used at Savannah River Site (SRS) is a liquid slurry feed joule-heated ceramic melter. The physical nature of a joule-heated meter is complex and involves interactions between electric, thermal, and flow fields. These interactions take place through strongly temperature-dependent glass properties, natural convection, advection, diffusion, and volumetrically distributed joule heating sources. The cold feed on top of heated glass distabilizes the flow field and develops unsteady asymmetric flow motions underneath. Thus waste glass modeling requires solving a full 3-D, unsteady, momentum, energy, and electric equation with temperature-dependent properties. Simulation of noble metal deposit process requires an additional mass diffusion equation that is coupled to the momentum equation through mass advection term. The objective of this paper is to identify critical issues anticipated in the Defense Waste Process Facility (DWPF) melter operation and address how these issues can be resolved with current state-of-the-art mathematical modeling techniques.

The results of this analysis quantified the uncertainty associated with monitoring the Axial Power Shape (APS) in the Savannah River Reactors. Thermocouples at each assembly flow exit map the radial power distribution and are the primary means of monitoring power in these reactors. The remaining uncertainty in power monitoring is associated with the relative axial power distribution. The APS is monitored by seven sensors that respond to power on each of nine vertical Axial Power Monitor (APM) rods. Computation of the APS uncertainty, for the reactor power limits analysis, started with a large database of APM rod measurements spanning several years of reactor operation. A computer algorithm was used to randomly select a sample of APSs which were input to a code. This code modeled the thermal-hydraulic performance of a single fuel assembly during a design basis Loss-of Coolant Accident. The assembly power limit at Onset of Significant Voiding was computed for each APS. The output was a distribution of expected assembly power limits that was adjusted to account for the biases caused by instrumentation error and by measuring 7 points rather than a continuous APS. Statistical analysis of the final assembly power limit distribution showed that reducing reactor power …

Accountability and nuclear safety concerns arising from uncertainties in Pu-239 loadings of a number of waste containers at SRS were investigated by in situ neutron and gamma-ray measurements and an assessment of risk stemming from past waste analysis and packaging practices. The neutron and gamma measurements largely confirmed the correctness of original waste analysis and accountability, while the risk assessment and measurement implications suggested no present or foreseeable nuclear safety problems.

Aluminum-27 Double Rotation NMR spectroscopy (DOR) has been used to investigate framework ordering in the aluminophosphate molecular sieves VPI-5, AlPO{sub 4}-5, and AlPO{sub 4}-8. Well resolved peaks in the {sup 27}Al DOR spectra of both hydrated and dehydrated VPI-5 allow isotropic shifts to be correlated with local framework structure. more distorted aluminum environments are reflected by broader lines in {sup 27}Al DOR spectra of AlPO{sub 4}-5 and AlPO{sub 4}-8.

A series of picosecond experiments and computer simulations will be presented that test collisional and hydrodynamic models for vibrational relaxation in liquids. The relationships between isolated binary collision models (IBC) and stochastic dynamics will be presented. The appropriateness of IBC theory in describing vibrational relaxation in liquids will also be discussed.

Semiclassical and quantum mechanical transition state theory is reviewed and two new approaches described. One is general implementation of a semiclassical rate expression that involves the good'' action-angle variables associated with the saddle point (i.e., transition state) of a potential energy surface. The other is an evaluation of a formally exact quantum expression for the rate in terms of Siegert eigenvalues associated with the transition state. Siegert eigenvalues are usually associated with scattering resonances, so their identification with the saddle point of a potential surface, and the expression for the reaction rate in terms of them, is quite an unexpected and novel development. 14 refs.

The computer codes used at Brookhaven National Laboratory to compute BWR safety parameters are the Engineering Plant Analyzer (EPA) and RAMONA-3B/MOD1. Both codes have the same methodology for modeling thermal hydraulic phenomena: drift-flux formulation, two-phase multipliers for the wall friction and form losses calculations, and the momentum integral approach for spatial integration of the loop momentum equations. Both codes use explicit integration methods for solving ordinary differential equations. It is concluded that both the codes are capable of modelling the instability problems for a BWR. The accuracy of thermohydraulics codes predictions was assessed by modelling oscillatory FRIGG tests. Nodalizations studies showed that 24 axial nodes were sufficient for a converged solution, 12 axial nodes produced an error of 4.4% in the gain of the power to flow transfer function. The code predicted consistently the effects of power and inlet subcooling on gain and system resonance frequency. The comparisons showed that the code predicted the peak gains with a mean difference from experiments of 7% {plus minus} 30% for all the tests modeled. The uncertainty in the experimental data is {minus}11% to +12%. The mean difference in the predicted frequency at the peak gain is {minus}6% {plus minus} 14%.

Specialized miniature low cost video equipment has been effectively used in a number of remote, radioactive, and contaminated environments at the Savannah River Site (SRS). The equipment and related techniques have reduced the potential for personnel exposure to both radiation and physical hazards. The valuable process information thus provided would not have otherwise been available for use in improving the quality of operation at SRS.

The TMI-2 Vessel Investigation Project (VIP) Metallurgical Program is a part of the international TMI-2 Vessel Investigation Project being conducting jointly by the US Nuclear Regulatory Commission and the Organization for Economic Co-operation and Development (OECD). The overall project consists of three phases, namely (1) recovery of material samples from the lower head of the TMI-2 reactor, (2) examination and analysis of the lower head samples and the preparation and testing of archive material subjected to a similar thermal history, and (3) procurement, examination, and analysis of companion core material located adjacent to or near the lower head material. The specific objectives of the ANL Metallurgical Program, which comprises a major portion of Phase 2, are to prepare metallographic and mechanical test specimen blanks from the TMI-2 lower head material, prepare similar test specimen blanks from suitable archive material subjected to the appropriate thermal processing, determine the mechanical properties of the lower vessel head and archive materials under the conditions of the core-melt accident, and assess the lower head integrity and margin-to-failure during the accident. The ANL work consists of three tasks: (1) archive materials program, (2) fabrication of metallurgical and mechanical test specimens from the TMI-2 pressure vessel samples, …

The chemical decomposition of aqueous alkaline solutions of sodium tetraphenylborate, NaTPB, has been investigated. The focus of the investigation is on the determination of components which influence NaTPB decomposition. Copper(II) ions, solution temperature, and solution pH (hydroxide ion concentration) have all been demonstrated to affect NaTPB stability. Their relationship with each other and the stability of NaTPB has been determined. Based upon this knowledge, a method for stabilizing NaTPB was determined. Decomposition of a NaTPB solution was delayed with the addition of sodium hydroxide. In additional work, the elimination of oxygen from the reaction environment did not prevent NaTPB decomposition in the presence of copper(II) ions but did, however, affect the course of decomposition.

The Savannah River Site has conducted a study to statistically quantify differences in metals concentrations as a function of sampling device and filter treatment. Twelve wells screened in unconsolidated coastal plain sediments were sampled for the study. All wells had histories of detectable toxic metals concentrations. Unfiltered and filtered (using 10 and 0.45 micron filters) samples were collected from all wells to evaluate the effects of filtering. To compare the effects of sampling device, the wells were sampled twice, once with a bladder pump and once with a centrifugal pump. An analysis of covariance (ANCOVA) method was used to assess the effects of sampling device and filtration on metals concentrations considering the variation in pH, conductivity, and turbidity among samples. This study demonstrates that when controlled sampling techniques are employed, differences in toxic metals concentrations between filtered and unfiltered samples are not statistically significant. However, variations in sampling devices yield samples with statistically different metals concentrations. The centrifugal pumps, which cause more agitation of the sample and the screened zone than bladder pumps, yield samples with statistically higher metals concentrations.

The higher order mode attenuation scheme proposed for the Advanced Light Source accelerating cavities consists of two broad-band dampers placed 90{degrees} apart on the outer edge. In order to assess the damping efficiency a test assembly was built. The HOM damping was obtained by comparing the peak values of the transmission through the cavity for both the damped and the undamped case. Because of the high number of modes and frequency shifts due to the damping gear, the damping was assessed statistically, by averaging over several modes. In the frequency range from 1.5 to 5.5 GHz, average damping greater than 100 was obtained. 1 ref., 6 figs.

An innovative environmental restoration technology, in situ air stripping, has been demonstrated at the US Department of Energy (DOE) Savannah River Site (SRS) in South Carolina. This process, using horizontal wells, is designed to concurrently remediate unsaturated-zone soils and ground water containing Volatile Organic Compounds (VOC). In situ technologies have the potential to substantially reduce costs and time required for remediation as well as improve effectiveness of remediation. Horizontal wells were selected to deliver and extract fluids from the subsurface because their geometry can maximize the efficiency of a remediation system and they have great potential for remediating contaminant sources under existing facilities. The first demonstration of this new technology was conducted for a period of twenty weeks. A vacuum was first drawn on the vadose zone well until a steady-state removal of VOCs was obtained. Air was then injected at three different rates and at two different temperatures. An extensive characterization program was conducted at the site and an extensive monitoring network was installed prior to initiation of the test. Significant quantities of VOCs have been removed from the subsurface (equivalent to an eleven-well, 500-gpm, pump-and-treat system at the same site). Concentrations of VOCs in the ground water have …

A review of the Savannah River Site production reactor systems was initiated in 1980 and led to implementation of the Reactor Materials Program in 1984 to assess reactor safety and reactor service life. The program evaluated performance of the reactor tanks, primary coolant piping, and thermal shields, components of welded construction that were fabricated from Type 304 stainless steel. The structural integrity analysis of the primary coolant system has shown that the pressure boundary is not susceptible to gross rupture, including a double ended guillotine break or equivalent large area bank. Residual service life is potentially limited by two material degradation modes, irradiation damage and intergranular stress corrosion cracking. Analysis of the structural integrity of the tanks and piping has shown that continued safe operation of the reactors for several additional decades is not limited by the material performance of the primary coolant system. Although irradiation damage has not degraded material behavior to an unacceptable level, past experience has revealed serious difficulties with repair welding on irradiated stainless steel. Stress corrosion can be mitigated by newly identified limits on impurity concentrations in the coolant water and by stress mitigation of weld residual stresses. Work continues in several areas: the effects …

The Reversatron 2 RFP (R/a=50cm/8cm) has been operated with interchangeable shells to investigate resistive wall modes. Shell penetration times are 610, 100, and 4 {mu}sec (no shell). With the 610 {mu}sec shell, the plasma current is {le} 65 kA and the duration {le} 550 {mu}sec. With no shell, helium discharges are more resistive and hydrogen discharges cannot be sustained. An m=1, n=-6 mode resonant on axis grows to a relative amplitude of 20% during the setting-up phase. With the 100{mu}sec shell, deuterium discharges can be sustained but are degraded due to a broad spectrum of modes. The increased plasma resistance can be correlated with the flux intersecting the wall. 21 refs., 12 figs.

This work describes a number of experimental observations on the structure and behavior of {Sigma}99 and other near-90{degree} <110> tilt boundaries in bicrystals of aluminum. The continuous bicrystal structure employed in these studies is based on the symmetry properties inherent in heteroepitaxial growth. A thin film grown in this geometry consists of intertwined grains surrounding each other but with only two grain orientations.

None

Changes in perspectives on fast reactor safety have occurred over the past ten years due both to technical progress and to the course of events. The major aspect of these changes is that they relate to basic design decisions that are largely, but not exclusively, related to safety considerations. Among the topics discussed are inherent safety, choice of fuel between metal and oxide, choice of reactor configuration between pool and loop, impact of size on safety characteristics and modularity, containment options, and treatment of the hypothetical core disruptive accident.

Free-electron lasers as scientific instruments are reviewed. The present status and future prospects are delineated with attention drawn to the size, complexity, availability, and performance capability of this new tool. The Free-Electron Laser (FEL) was proposed by John Madey in 1970 (1), although earlier work, relevant to the concept, had been performed by Motz (2) and by Phillips (3). Experimental demonstration was achieved by Madey, et. al. in 1975 and 1976 (4). Since that time, FELs of diverse configurations have been operated at several laboratories around the world. At present, FEL development is focused in two directions: in constructing reliable FELs for scientific research and in extending FEL capability to vacuum ultra-violet (VUV) and even shorter wavelengths. In this article we shall only very briefly review the principles of an FEL, putting emphasis on those aspects that limit performance, after which we shall discuss the applications, present status and future prospects of FELs. Much material that we wish to present is in the form of Tables, and they are an essential part of this article.