A mathematical model of a packed column was developed to describe the removal of benzene from radioactive salt solutions at the Savannah River Site. The model was developed from existing, generalized mass transfer correlations for randomly dumped packing, and the correlations were adapted for structured packing. Thermophysical data specific to the solutions of interest were incorporated into the model. Verification of the code was completed using operating data from stripping columns at other locations.

The Advanced Neutron Source (ANS) is a new user experimental facility planned to be operational at Oak Ridge in the late 1990's. The centerpiece of the ANS will be a steady-state research reactor of unprecedented thermal neutron flux ({phi}{sub th} {approx} 9{center dot}10{sup 19} m{sup -2}{center dot}s{sup -1}) accompanied by extensive and comprehensive equipment and facilities for neutron-based research. 5 refs., 5 figs.

To improve the tritium release characteristics of lithium ceramics, we are investigating the effects of dopants on tritium transport and release. Prior work has suggested a correlation between tritium and lithium diffusion in lithium-containing ceramics. This correlation has led us to propose a mechanism for tritium diffusion in which the tritium diffuses in the form of a lithium vacancy-triton complex. If this is the case, one should be able to increase the tritium diffusivity by increasing the number of lithium vacancies and thereby increasing the number of vacancy-triton complexes. The size of the increase in the diffusivity, however, will be dependent upon several parameters, including the binding energy of the vacancy-triton complex. Our calculations indicate that, under conditions comparable to those in some in-pile irradiation experiments, a binding energy of around 84 kJ/mol should increase the diffusivity and lead to a decrease in the steady-state tritium inventory by about a factor of six. 21 refs., 2 tabs.

The objectives of the subscale test program were designed to provide sorbent and additive selection guidance, and, in so doing, supply answers to the questions posed in the preceding section. The objectives are: Identify the best commercial hydrate sorbent and the best enhanced hydrate sorbent from a list of nine types, based upon S0{sub 2} removal at Ca/S=2. Determine the relative effectiveness of sodium sesquicarbonate versus sodium bicarbonate for S0{sub 2} and NO{sub x} control over the temperature range of 200{degrees}F--400{degrees}F. Identify the best NO{sub 2} suppressing additive among the group of ammonia, urea, and activated carbon.

The state of the art in semiconductor detectors for elementary particle physics and x-ray astronomy is briefly reviewed. Semiconductor detectors are divided into two groups; classical semiconductor diode detectors; and semiconductor memory detectors. Principles of signal formation for both groups of detectors are described and their performance is compared. New developments of silicon detectors are reported here. 13 refs., 8 figs.

Our research at Yale on the fate of nuclides in natural water systems has three components to it: the study of the atmospheric precipitation of radionuclides and other chemical species; the study of the behavior of natural radionuclides in groundwater and hydrothermal systems; and understanding the controls on the distribution of radionuclides and stable nuclides in the marine realm. In this section a review of our progress in each of these areas is presented.

An experiment was conducted to better understand a frequent layer of northwest winds found in the Northern Arizona region. This layer has been observed most often in winter near the surface at Page, Arizona, and often opposes larger scale upper level west winds. The results of this experiment improved both the temporal and the down-valley spatial resolution of the flow structure in this region during winter. 11 refs., 9 figs.

This paper discusses the differences and similarities between modern nuclear physics and particle physics. Similarities are presented between QED and QCD. (LSP)

The Savannah River Site manufactures nuclear materials for the US Department of Energy. In recent years robots and mobile teleoperators have been used to reduce the radiation exposure of personnel at this site. Two examples of robots that have significantly reduced radiation exposure are the Shielded Cells Waste Handling Robot and the Shielded Cells Sample Handling Robot. The Shielded Cells Waste Handling Robot has been in operation for over four years. It removes cans of radioactive waste from the Shielded Cells, seals the can in a plastic bag, and places the cans in a waste drum. The Shielded Cells Sample Handling Robot has been in operation for only a few months. It opens a door to one of the Shielded Cells, removes a radioactive sample from a shielded container, laces it in the cell, and closes the door. Two examples of tasks where mobile teleoperators have significantly reduced radiation exposure are removal of a contaminated junction box, and lead removal from radioactive vessels. In the first example, radioactive liquid had leaked into an obsolete junction box. This caused the box to be internally contaminated to a level of 200 Rem/hr. at the surface. A mobile teleoperator was used to remove …

The GALLEX collaboration aims at the detection of solar neutrinos in a radiochemical experiment employing 30 tons of Gallium in form of concentrated aqueous Gallium-chloride solution. The detector is primarily sensitive to the otherwise inaccessible pp-neutrinos. Details of the experiment have been repeatedly described before. Here we report the present status of implementation in the Laboratori Nazionali del Gran Sasso (Italy). So far, 12.2 tons of Gallium are at hand. The present status of development allows to start the first full scale run at the time when 30 tons of Gallium become available. This date is expected to be January, 1990. 17 refs., 16 figs.

Under a previous contract with Morgantown Energy Technology Center (METC), Department of Energy (DOE) Contract No. AC21-84MC21108, UCC Research Corporation (UCCRC) built and tested a 1500 lb/day Mild Gasification Process Development Unit (MGU). The MGU, as tested under the previous contract, is shown in Figure 1. Testing completed under the previous contract showed that good quality hydrocarbon liquids and good quality char can be produced in the MGU. However, the MGU is not optimized. The primary objectives of the current project are to optimize the MGU and determine the suitability of char for several commercial applications. The program consists of four tasks; Task 1 -- Test Plan; Task 2 -- Optimization of Mild Gasification Process; Task 3 -- Evaluation of Char and Char/Coal Blends as a Boiler/Blast Furnace Fuel; and Task 4 -- Analysis of Data and Preparation of Final Report. Task 1 has been completed while work continued on Task 2.

In recent years, part of the experimental effort on the FRX-C/LSM device has been devoted to understanding why good FRC confinement is observed only in a narrow window of the operating parameter space (fill pressures less than 5 mtorr and bias fields less than 0.8--0.9 kG). The transition from good to bad confinement has been shown for some time to correlate with strong axial shocks, suggesting a formation or stability problem. More recently, FRC magnetic asymmetries have been observed whenever the confinement was poor. To gain further understanding, a 64-coil probe array was built, and data from over 700 discharges were collected during the summer of 1989. We summarize in this paper the results of a preliminary analysis of these data. 5 refs., 4 figs.

The US Bureau of Mines publication presents the results of investigations into the fire and explosion hazards of oil shale rocks and dust. Three areas have been examined: the explosibility and ignitability of oil shale dust clouds, the fire hazards of oil shale dust layers on hot surfaces, and the ignitability and extinguishment of oil shale rubble piles. 10 refs., 54 figs., 29 tabs.

Demonstration that advanced reactor designs satisfy safety and performance goals requires the analysis of uncertainties in calculated reactor characteristics. Two of the important performance characteristics of advanced liquid metal reactors (LMR) are the burnup reactivity swing and the local power peaking factor. Previous work reported a study of the uncertainty in the burnup reactivity swing attributable to nuclear data uncertainties for a typical advanced LMR design. The results are reported here of some recent investigations into the uncertainty in the core power distribution after the completion of a burnup cycle. 11 refs., 1 fig., 2 tabs.

JACEE balloon-borne emulsion chamber detectors are used to observe the spectra and interactions of cosmic ray protons and nuclei in the energy range 1-100A TeV. Experience with long duration mid-latitude balloon flights and characteristics of the detector system that make it ideal for planned Antarctic balloon flights are discussed. 5 refs., 2 figs.

Spatial adaptation, in the form of a frequency-specific reduction in contrast sensitivity, can occur when the visual system is exposed to certain stimuli. We employed vertical sinusoidal test gratings to investigate adaptation to the horizontal structure of text presented on a standard video display terminal. The parameters of the contrast sensitivity test were selected on the basis of waveform analysis of spatial luminance scans of the text stimulus. We found that subjects exhibited a small, but significant, frequency-specific adaptation consistent with the spatial frequency spectrum of the stimulus. Theoretical and practical significance of this finding are discussed. 6 refs., 4 figs.

We discuss possible sources of new interactions in beta-decay and the role of beta-decay experiments in obtaining information on them. 46 refs.

The generation of vibrationally excited molecules by electron excitation collisions and the subsequent generation of negative ions by dissociative attachment to these molecules has become a standard model for volume source operation. These processes have been supplemented recently by the demonstration of atom-surface recombination to form vibrationally excited molecules, and enhanced negative ion formation by protons incident upon barium electrodes. In this paper we consider the additional processes of molecular vibrational excitation generated by recombination of molecular ions on the electrode surfaces, and negative ion formation by vibrationally excited molecules rebounding from low work-function electrodes. 10 refs., 4 figs.

The current CTX program is directed towards using spheromaks as an energy transfer medium to accelerate metal plates to hypervelocity. In the proposed scheme, the spheromak is first compressed by accelerating a large plate to moderate velocity (3--5 km/s) with high explosives (HE). Another smaller plate is designed such that it experiences little force until the spheromak is compressed to a size comparable to the small plate. Then the force on the small plate rises quickly, accelerating this plate to high velocity. Present theoretical calculations indicate velocity gain of the small plate over the large plate as high as four, which could produce 20 km/s small plate velocity. In principle, the final velocity is limited only by the sound speed of the spheromak, and in practice, is probably limited by ohmic heating in the plate, the amount of energy that can be delivered to the large compression plate, and the energy dissipated by the spheromak during compression. Taking these effects into account, final velocities in the range 40--100 km/s might be achievable. 8 figs.

I'll discuss the experiments in which parity violation has been measured in low energy neutron-nucleus scattering. The interest is two-fold: to understand how parity violation in the nucleon-nucleon (NN) interaction manifests itself in a complicated many-body system and to show that the large enhancements observed make this a good laboratory to search for violations of TRI. Further, the procedure of relating the measured parity violating asymmetries to the under-lying NN interaction will be important in order to make the same connection in violation of TRI (or in limits). First, I'll make brief comments on some relevant features of low energy neutron scattering and then review the existing measurements of parity violation. I'll try to explain, at least qualitatively, the origin of the large enhancements observed. Finally, I'll describe the TRIPLE collaboration program to study parity violation and discuss planned experiments to search for violations of TRI. 23 refs.

Thin films of the Tl-based superconductors often have relatively poor properties because of film/substrate interdiffusion which occurs during the anneal. We have therefore investigated the use of BaF{sub 2} as a diffusion barrier. TlCaBaCuO thin films were deposited by dc magnetron sputtering onto MgO <100> substrates, both with and without an evaporation-deposited BaF{sub 2} buffer layer, and post-annealed in a Tl over-pressure. Electrical properties of the films were determined by four-point probe analysis, and compositions were measured by ion-backscattering spectroscopy. Structural analysis was performed by x-ray diffraction and scanning electron microscopy. The BaF{sub 2} buffer layers were found to significantly improve the properties of the TlCaBaCuO thin films. 8 refs., 3 figs.

This project was concerned with high-accuracy measurements of electron-impact photoemission cross sections for transitions of atoms and molecules in the EUV spectral region (30 nm to 200 nm). The spectrometer-detector system that was employed in the measurements was calibrated using well-parameterized synchrotron radiation. The 58.4 resonance line of He was chosen to establish the overall accuracy of the apparatus and data collection procedures. The measurement of this line can be compared to accurate theoretical calculations and to one other experimental cross section measurement in which a different excitation channel was observed.

The objective of this contract is to develop a consistent technical data base on the use of iron-based catalysts in Fischer-Tropsch (FT) synthesis reactions. This data base will be developed to allow the unambiguous comparison of the performance of these catalysts with each other and with state-of-the-art iron catalyst compositions. Particular attention will be devoted to generating reproducible kinetic and selectivity data and to developing reproducible improved catalyst compositions.

During the past few years there have been significant advances in our understanding of nuclei excited into states of high angular momentum. The development of large multi-detector arrays for {gamma}-{gamma} coincidence spectroscopy studies has propelled the amount of new experimental information available and this has been complemented by notable advances in the theoretical treatments of high-spin phenomena. To provide yet a more detailed understanding of the structure of these high-spin states and to provide a stringent test of these models, we have resorted to measurements of their dynamic electromagnetic multipole moments which are a direct reflection of the collective aspects of the nuclear wave functions. For the most part, these multipole moments are obtained by lifetime measurements utilizing Doppler-shift techniques. Let me stress that the great value of lifetime measurements is that they provide the transition matrix elements without the necessity to rely on nuclear models. 24 refs., 10 figs.