The operational performance of a six-pack'' of cermet anodes and corrosion rates was evaluated in a six kA pilot reduction cell at Reynolds' Manufacturing Technology Laboratory. Two separate test periodswere conducted with the cermet anodes; the first period was in conjunction with the Pacific Northwest Laboratory and the second with ELTECH Research Corporation. Both tests used identical NiO-NiFe[sub 2]O[sub 4]-Cu anodes manufactured by Ceramic Magnetics, Inc.. The ELTECH testing involved the in situ coating of the anodes with cerium oxide. Primary evaluations for both test periods were conducted at target conditions of alumina saturation and 0.5 amp/cm[sup 2] anode current density. Individual anodes remained in operation for 25 days during the two and one-half month testing period. Operational difficulties developed throughout the test due to breakage of the anode conductor stems, cracking and breaking of the cermet anodes, unequal anode current distribution, and alumina muck build-up in the cell. These operational problems are discussed as well as an estimate of anode corrosion rates based on metal impurity levels in the aluminum metal pad.

The operational performance of a ``six-pack`` of cermet anodes and corrosion rates was evaluated in a six kA pilot reduction cell at Reynolds` Manufacturing Technology Laboratory. Two separate test periodswere conducted with the cermet anodes; the first period was in conjunction with the Pacific Northwest Laboratory and the second with ELTECH Research Corporation. Both tests used identical NiO-NiFe{sub 2}O{sub 4}-Cu anodes manufactured by Ceramic Magnetics, Inc.. The ELTECH testing involved the in situ coating of the anodes with cerium oxide. Primary evaluations for both test periods were conducted at target conditions of alumina saturation and 0.5 amp/cm{sup 2} anode current density. Individual anodes remained in operation for 25 days during the two and one-half month testing period. Operational difficulties developed throughout the test due to breakage of the anode conductor stems, cracking and breaking of the cermet anodes, unequal anode current distribution, and alumina muck build-up in the cell. These operational problems are discussed as well as an estimate of anode corrosion rates based on metal impurity levels in the aluminum metal pad.

High gradient magnetic separation (HGMS) is a physical separation process that is used to extract magnetic particles from mixtures. The technology is used on a large scale in the kaolin clay industry to whiten or brighten kaolin clay and increase its value. Because all uranium and plutonium compounds are slightly magnetic, HGMS can be used to separate these contaminants from non-magnetic soils. A Cooperative Research and Development Agreement (CRADA) was signed in 1992 between Los Alamos National Laboratory (LANL) and Lockheed Environmental Systems and Technologies Company (LESAT) to develop HGMS for soil decontamination. This paper reports progress and describes the HGMS technology.

There is concern about the risk of uncontrolled exothermic reaction(s) in Hanford Site waste tanks containing NO{sub 3}{sup {minus}}/NO{sub 2} based salts and/or metal hydroxide sludges in combination with organics or ferrocyanides. However, gradual oxidation of the waste in the tanks to less reactive species appears to have reduced the risk. In addition, wastes sampled to date contain sufficiently large quantities of water so that propagation reactions are highly unlikely. This paper investigates various aspects of the aging of Hanford tank wastes.

There is concern about the risk of uncontrolled exothermic reactions(s) in Hanford Site waste tanks containing NO{sub 3{sup minus}}/NO{sub 2{sup minus}} based salts and/or metal hydroxide sludges in combination with organics or ferrocyanides. However, gradual oxidation of the waste in the tanks to less reactive species appears to have reduced the risk. In addition, wastes sampled to date contain sufficiently large quantities of water so that propagation reactions are highly unlikely. This report details an investigation into the risk of an uncontrolled exothermic reaction in Hanford Site high-activity water tanks.

High-activity radioactive waste has been stored in large underground storage tanks at the US Department of Energy`s (DOE) Hanford Site in Eastern Washington State since 1944. Since then, more than 227,000 m{sup 3} (60 Mgal) of waste have been accumulated in 177 tanks. These caustic wastes consist of many different chemicals. The waste forms include liquids, slurries, salt cakes, and sludges. A number of safety issues have been raised about these wastes, and resolution of these issues is a top priority of DOE. A Waste Tank Safety Program has been established to resolve these high-priority safety issues. This paper will deal with three of these issues. The issues described are the release of flammable vapors from single- and double-shell tanks, the existence of organic chemicals, and/or ferrocyanide ion-containing fuel-rich mixtures of nitrate and nitrite salts in single-shell tanks.

The Grout Treatment Facility (GTF) at Hanford, Washington will process the low-level fraction of selected double-shell tank (DST) wastes on the Hanford Site, to produce a cementitious waste form. This facility, which is operated by Westinghouse Hanford Company (Westinghouse Hanford), mixes liquid wastes with cementitious materials and pumps the resulting grout slurry into large [5,300 cubic meters (m{sup 3})] concrete vaults. Once in the vault, the grout cures to produce a waste form that immobilizes radioactive and hazardous constituents through chemical reactions and/or microencapsulation. Although this disposal scheme has several advantages, pouring grout into large vaults raises concerns about how to handle the heat generated from the exothermic hydration reactions that occur as the grout cures. WHC`s current strategy for addressing the problem of hydration heat is to fill the vault in stages and use forced ventilation in the airspace above the grout to speed heat removal. The varying composition of Hanford tank waste requires that each tank be processed in a separate campaign using a grout formulation specifically designed for that waste. The next tank scheduled for treatment is DST 241-AN-106. A four-phase process for developing the grout formulation development process is used to assure that the formulation will …

Long lengths of flexible Ag-clad Bi-2223 Superconductors have been fabricated by the powder-in-tube technique using prereacted, poly-phase, Pb-doped Bi-Sr-Ca-Cu-O powders. At liquid helium (4.2 K) temperature, improved process conditions yielded transport critical current density (J{sub c}) values greater than 10{sup 5} A/cm{sup 2} at zero field; at liquid nitrogen (77K) temperature, the J{sub c} values of short tape samples exceeded 4 {times} 10{sup 4} A/cm{sub 2}. Rolled tapes are cut into lengths up to 2 - meters long and are used in parallel to fabricate small superconducting pancake coils by the ``wind-and-react`` technique. The cots are characterized at 77K and 4.2 K. The J{sub c} of the coils are up to 80% of the short, rolled sample result at 77 K. The coils exhibited these results even after being cooled and warmed several times between ambient, 77 K and 4.2 K, indicating their stability following thermal cycling.

Long lengths of flexible Ag-clad Bi-2223 Superconductors have been fabricated by the powder-in-tube technique using prereacted, poly-phase, Pb-doped Bi-Sr-Ca-Cu-O powders. At liquid helium (4.2 K) temperature, improved process conditions yielded transport critical current density (J[sub c]) values greater than 10[sup 5] A/cm[sup 2] at zero field; at liquid nitrogen (77K) temperature, the J[sub c] values of short tape samples exceeded 4 [times] 10[sup 4] A/cm[sub 2]. Rolled tapes are cut into lengths up to 2 - meters long and are used in parallel to fabricate small superconducting pancake coils by the wind-and-react'' technique. The cots are characterized at 77K and 4.2 K. The J[sub c] of the coils are up to 80% of the short, rolled sample result at 77 K. The coils exhibited these results even after being cooled and warmed several times between ambient, 77 K and 4.2 K, indicating their stability following thermal cycling.

This paper describes the corrosion processes that occurred following the mechanical failure of two steel 14-ton storage cylinders containing depleted UF{sub 6}. The failures both were traced to small mechanical tears that occurred during stacking of the cylinders. Although subsequent corrosion processes greatly extended the openings in the wall. the reaction products formed were quite protective and prevented any significant environmental insult or loss of uranium. The relative sizes of the two holes correlated with the relative exposure times that had elapsed from the time of stacking. From the sizes and geometries of the two holes, together with analyses of the reaction products, it was possible to determine the chemical reactions that controlled the corrosion process and to develop a scenario for predicting the rate of hydrolysis of UF{sub 6}, the loss rate of HF, and chemical attack of a breached UF{sub 6} storage cylinder.

This paper presents an analysis of the possibility of designing an high energy {mu}{sup {minus}} collider based on electro-production of muons. An analytic expression for the pair production cross-section yields an expression for the electron-to-muon conversion efficiency. This quantity is connected to the luminosity definition via the beam power on the production target. Sets of consistent parameters are then derived as a function of electron beam and collider characteristics.

We present the results of measurements of the complex permittivity and permeability over a frequency range of 0.1-5.1 GHz for a range of microwave absorbing materials used in a variety of accelerator applications. We also describe the automated measurement technique which uses swept-frequency S-parameter measurements made on a strip transmission line device loaded with the material under test.

The renewed interest in safety issues for large scale industrial devices and in high speed combustion has driven recent intense efforts to gain a deeper theoretical understanding of detonation wave dynamics. Linear stability analyses, weakly nonlinear bifurcation calculations as well as full scale multi-dimensional direct numerical simulations have been pursued for a standard model problem based on the reactive Euler equations for an ideal gas with constant specific heat capacities and simplified chemical reaction models. Most of these studies are concerned with overdriven detonations. This is true despite the fact that the majority of all detonations observed in nature are running at speeds close to the Chapman-Jouguet (CJ) limit value. By focusing on overdriven waves one removes an array of difficulties from the analysis that is associated with the sonic flow conditions in the wake of a CJ-detonation. In particular, the proper formulation of downstream boundary conditions in the CJ-case is a yet unsolved analytical problem. A proper treatment of perturbations in the back of a Chapman-Jouguet detonation has to account for two distinct weakly nonlinear effects in the forward acoustic wave component. The first is a nonlinear interactionof highly temperature sensitive chemistry with the forward acoustic wave component in …

Magnetic characterization has been performed on the members of the cuprate-niobate RBa{sub 2}Cu{sub 2}NbO{sub 8} (R = Pr, Nd, and La) series and R{sub l.5}Ce{sub 0.5}Sr{sub 2}Cu{sub 2}NbO{sub 10} (R = Pr, Eu, Nd, and Sm) series. The PrBCNO samples show a signature in the magnetization of a magnetic ordering at 12 K. The PrCSCNO sample is non-superconducting and shows two distinct orderings at 17 and 53 K. No such magnetic phase transition is observed down to 2 K in the Nd and La based RBCNO materials or the Nd, Sm, and Eu based RCSCNO materials. Measurements of the lower critical field curve, dc irreversibility line, and critical current densities are reported for each of the superconducting NdCSCNO, SmCSCNO, and EuCSCNO compounds.

Adaptive mesh refinement has proven itself to be a useful tool in a large collection of applications. By refining only a small portion of the computational domain, computational savings of up to a factor of 80 in 3 dimensional calculations have been obtained on serial machines. A natural question is, can this algorithm be used on massively parallel machines and still achieve the same efficiencies? We have designed a data layout scheme for mapping grid points to processors that preserves locality and minimizes global communication for the CM-200. The effect of the data layout scheme is that at the finest level nearby grid points from adjacent grids in physical space are in adjacent memory locations. Furthermore, coarse grid points are arranged in memory to be near their associated fine grid points. We show applications of the algorithm to inviscid compressible fluid flow in two space dimensions.

A field test was conducted to evaluate the performance of Six-Phase Soil Heating to enhance the removal of contaminants. The purpose of the test was to determine the scale-up characteristics of the Six-Phase Soil Heating technology and to evaluate a computer process simulator developed for the technology. The test heated a 20-ft diameter cylinder of uncontaminated soil to a 10-ft depth. Six-phase ac power was applied at a rate of 30--35 kW using a power system built from surplus electrical components. The test ran unattended, using a computer-based system to record data, alert staff of any excursions in operating conditions via telephone, and provide automatic shut-off of power depending on the type of excursion. The test data included in situ soil temperatures, voltage profiles, and moisture profiles (using a neutron-probetechnique). After 50 days of heating, soil in the center of the array at the 6-ft depth reached 80{degrees}C. Soil temperatures between the two electrodes at this depth reached approximately 75{degrees}C. Data from this test were compared with those predicted by a computer process simulator. The computer process simulator is a modified version of the TOUGH2 code, a thermal porous media code that can be used to determine the movement of …

A field test was conducted to evaluate the performance of Six-Phase Soil Heating to enhance the removal of contaminants. The purpose of the test was to determine the scale-up characteristics of the Six-Phase Soil Heating technology and to evaluate a computer process simulator developed for the technology. The test heated a 20-ft diameter cylinder of uncontaminated soil to a 10-ft depth. Six-phase ac power was applied at a rate of 30--35 kW using a power system built from surplus electrical components. The test ran unattended, using a computer-based system to record data, alert staff of any excursions in operating conditions via telephone, and provide automatic shut-off of power depending on the type of excursion. The test data included in situ soil temperatures, voltage profiles, and moisture profiles (using a neutron-probetechnique). After 50 days of heating, soil in the center of the array at the 6-ft depth reached 80[degrees]C. Soil temperatures between the two electrodes at this depth reached approximately 75[degrees]C. Data from this test were compared with those predicted by a computer process simulator. The computer process simulator is a modified version of the TOUGH2 code, a thermal porous media code that can be used to determine the movement of …

Subjects judged the orientation of a 2 min. gap Landolt C located at a distance of 2.4 m. The stimuli were presented in central vision on a CRT, at low to medium contrast. The effects of varying the spectrum and luminance of surround lighting were assessed on both pupil size (measured using infrared pupillometry during task performance) and task accuracy. The task display was protected from the surround lighting, so that its luminance and contrast could be varied independently of the changes in the surround lighting. Indirect surround illumination was provided by either two illuminants of very different scotopic spectral content but with the same photopic luminance (Experiments 1 and 3), or by using the same illuminant at two different luminance levels (Experiment 2). In Experiment 3, the effect of changing surround spectrum was compared to the effect of varying task background luminance between 12 cd/m{sup 2} and 73 cd/m{sup 2}. In all experiments, scotopically enhanced surround lighting produced pupil areas which were reduced by almost 50% in comparison with surround lighting with relatively less scotopic luminance. Concomitantly there was improvement in Landolt C task performance with the scotopically enhanced surround lighting at all contrast and luminance levels. In these …

Subjects judged the orientation of a 2 min. gap Landolt C located at a distance of 2.4 m. The stimuli were presented in central vision on a CRT, at low to medium contrast. The effects of varying the spectrum and luminance of surround lighting were assessed on both pupil size (measured using infrared pupillometry during task performance) and task accuracy. The task display was protected from the surround lighting, so that its luminance and contrast could be varied independently of the changes in the surround lighting. Indirect surround illumination was provided by either two illuminants of very different scotopic spectral content but with the same photopic luminance (Experiments 1 and 3), or by using the same illuminant at two different luminance levels (Experiment 2). In Experiment 3, the effect of changing surround spectrum was compared to the effect of varying task background luminance between 12 cd/m[sup 2] and 73 cd/m[sup 2]. In all experiments, scotopically enhanced surround lighting produced pupil areas which were reduced by almost 50% in comparison with surround lighting with relatively less scotopic luminance. Concomitantly there was improvement in Landolt C task performance with the scotopically enhanced surround lighting at all contrast and luminance levels. In these …

This report discusses a desk-top computer program has been developed for estimating the costs, waste volumes, and occupational radiation exposures associated with decommissioning light-water reactor power stations. Cost categories and cost algorithms used in the program are discussed and a brief description of the user interface is given.

This report discusses a desk-top computer program has been developed for estimating the costs, waste volumes, and occupational radiation exposures associated with decommissioning light-water reactor power stations. Cost categories and cost algorithms used in the program are discussed and a brief description of the user interface is given.

The ALEXIS experiment (Array of Low Energy X-ray Imaging Sensors), is a mini-satellite containing six wide angle EUV/ultrasoft x-ray telescopes. Its purpose is to map out the sky in three narrow (5%) bandpasses around 66, 71, and 93 eV. The 66 and 71 eV bandpasses are centered on intense Fe emission lines which are characteristic of million-degree plasmas such as the one thought to produce the soft x-ray background. The 93 eV bandpass is not near any strong emission lines and is more sensitive to continuum sources. The mission will be launched on the Pegasus Air-Launched Vehicle in early 1993 into a 400-nautical-mile, high-inclination orbit and will be controlled entirely from a small ground station located at Los Alamos. The project is a collaborative effort between Los Alamos National Laboratory, Sandia National Laboratory, and the University of California-Berkeley Space Sciences Laboratory.

Among the new facilities to be offered by the National Science Foundation through the National High Magnetic Field Laboratory (NHMFL) are pulsed fields that can only be achieved at a national user facility by virtue of their strength, duration, and volume. In particular, a 44 mm bore pulsed magnet giving a 60 tesla field for 1 00 ms is in the final design stage. This magnet will be powered by a 1.4 GW motor-generator at Los Alamos and is an important step toward proving design principles that will be needed for the higher field quasi-stationary pulsed magnets that this power source is capable of driving.

Recent interest in understanding climate and climate change at regional-scales has led to the application of mesoscale models for regional climatology studies. These models can provide an understanding of climate processes in a physically consistent way at much higher resolution than presently offered by GCMs. In recent work, we have tried to address questions in the RAMS mesoscale model to establish confidence in our modeling procedure. A more rigorous comparison of our modeling results with various data sets is reported in Roads et al. (1992). In the present paper, we use two simple numerical experiments to examine the impact of grid configuration on the predicted precipitation field from the RAMS model. We intend to demonstrate that the choice of the lateral boundaries and grid configurations can significantly impact the predicted fields of interest.