The effects of 0.10 M Cu/sup 2 +/, Hg/sup 2 +/, Zn/sup 2 +/, La/sup 3 +/, Ce/sup 3 +/, Al/sup 3 +/, Th/sup 4 +/,Zr/sup 4 +/, Cr/sup 3 +/, and Fe/sup 3 +/ on PuO/sub 2/ dissolution in 8.0M HNO/sub 3/--0.1M HF were investigated. Except for Cr/sup 3 +/ and Fe/sup 3 +/, the amount of Pu dissolved in 1 hour can be predicted by either log C(Pu) = -0.32 log K/sub F/ - 1.53 (K/sub F/ = first stability constant for the impurity metal fluoride complex) or log C(Pu) = -0.5 Z/sup 2//d-1.11 (Z = ionic charge of impurity cation, d = sum of impurity cation and fluoride ionic radii in angstroms) (DLC)

When an electrostatic tandem accelerator is used primarily for heavy ion acceleration, numerous communication channels with the high voltage terminal are desirable. The ANL FN tandem operates at a tank pressure of 100 psi SF/sub 6/ at terminal voltages up to 9.5 MeV. A low powered He-Ne laser with 15 percent modulation has been successfully tested in the terminal under normal operating conditions. Such a system allows the transmission of information without the use of light guides. Multistranded light guides did not withstand voltage gradients as low as 0.4 MV/m. Single core light guides with a diameter of 0.5 mm have been successfully operated at voltage gradients in excess of 1.7 MV/m. In addition to the laser a microprocessor has also been tested in the tandem terminal. With suitable protection, an 8080 microprocessor and a programmable ROM operated successfully for several weeks under normal operating conditions.

Conservation of water at the Los Alamos Scientific Laboratory (LASL) has been accomplished by recirculating evaporative cooling waters. Because of high silica concentration (80 mg/l) in Los Alamos groundwater, the concentration of recirculating water must be carefully controlled to prevent scaling. The most troublesome scale at Los Alamos has been identified as colloidal silica bound in a crystalline matrix of calcium carbonate. Several approaches to controlling this scale are: (1) chemical treatment using a chelate, sequestrant, or threshold approach, (2) softening, or (3) pH control. Silica alone will form deposits when supersaturated. In LASL systems, where silica concentrations are 200 to 240 mg/l, no problems have been observed. However, there is evidence that deposits are forming at slightly higher concentrations. These amorphous silica deposits are not as hard and tenacious as the calcium carbonate--silica scale. Complete external treatment, which combines silica removal and water softening, may be an economically competitive process for scale control. The advantages of slightly reducing the quantity of makeup water and drastically reducing the amount of blowdown water have environmental and conservation implications that may encourage the selection of complete treatment.

In 1984 Argonne National Laboratory (ANL) began an aggressive program of research and development based on the concept of a closed system for fast-reactor power generation and on-site fuel reprocessing, exclusively designed around the use of metallic fuel. This is the Integral Fast Reactor (IFR). Although the Experimental Breeder Reactor-II (EBR-II) has used metallic fuel since its creation 25 yeas ago, in 1985 ANL began a study of the characteristics and behavior of an advanced-design metallic fuel based on uranium-zirconium (U-Zr) and uranium-plutonium-zirconium (U-Pu-Zr) alloys. During the past five years several areas were addressed concerning the performance of this fuel system. In all instances of testing the metallic fuel has demonstrated its ability to perform reliably to high burnups under varying design conditions. This paper will present one area of testing which concerns the fuel system's performance under breach conditions. It is the purpose of this paper to document the observed post-breach behavior of this advanced-design metallic fuel. 2 figs., 1 tab.

The Tritium Plasma Experiment was assembled at Sandia National Laboratories, Livermore to investigate interactions between dense plasmas at low energies and plasma-facing component materials. This apparatus has the unique capability of replicating plasma conditions in a tokamak divertor with particle flux densities of 2 [times] 10[sup 19] ions/cm[sup 2] [center dot] s and a plasma temperature of about 15 eV using a plasma that includes tritium. With the closure of the Tritium Research Laboratory at Livermore, the experiment was moved to the Tritium Systems Test Assembly facility at Los Alamos National Laboratory. An experimental program has been initiated there using the Tritium Plasma Experiment to examine safety issues related to tritium in plasma-facing components, particularly the ITER divertor. Those issues include tritium retention and release characteristics, tritium permeation rates and transient times to coolant streams, surface modification and erosion by the plasma, the effects of thermal loads and cycling, and particulate production. A considerable lack of data exists in these areas for many of the materials, especially beryllium, being considered for use in ITER. Not only will basic material behavior with respect to safety issues in the divertor environment be examined, but innovative techniques for optimizing performance with respect to …

Two different requirements are driving engineering studies and hardware development to improve LAMPF. The first is concerned with component and system improvements to increase beam availability during the LAMPF production cycle. Hardware changes in RF, power supplies, and magnets are being implemented to increase mean time between failure and reduce time to replace or repair failed units. A joint LAMPF-Industry project is on-going to improve reliability of RF components. A component test stand is being refurbished to include significant development capability. The second approach includes several changes that will increase the duty factor of the existing accelerator. Major changes are being evaluated for replacing the front end of the accelerator. Other changes improving high brightness capability could result in a new performance plateau for LAMPF.

A V-10 wt % Ti alloy was irradiated with 2.7 MeV /sup 51/V/sup +/ at 650/sup 0/C to doses of 2 to 60 dpa. No void swelling was observed at any dose. The irradiation resulted in an enhancement of a precipitation process similar to that observed in unirradiated materials. The precipitates in irradiated specimens were found to have the NaCl-type cubic crystal structure with a lattice parameter of TiO. The orientation relationship between the matrix and the precipitates was the same as that observed under thermal equilibrium conditions in unirradiated materials.

During pilot scale operations of the Scale Glass Melter for the US Department of Energy a team of engineers and scientists was formed to assess the need for continued melter design development to support the Defense Waste Processing Facility (DWPF), and prioritize future efforts. Recently this has taken on new importance because of selection of the DWPF Melter design as the reference for the Hanford Waste Vitrification Project (HWVP), and increased interest at the West Valley Demonstration Project on melter life and replacement. Results of the study are summarized, and goals produced by the study are compared to the results of current programs at the Savannah River Laboratory (SRL).

The high-temperature diametral expansion and rupture behavior of Zircaloy-4 fuel-cladding tubes have been investigated in vacuum and steam environments under transient-heating conditions that are of interest in hypothetical loss-of-coolant accident situations in light-water reactors. The effects of internal pressure, heating rate, axial constraint, and localized temperature nonuniformities in the cladding on the maximum circumferential strain have been determined for burst temperatures between approximately 650 and 1350/sup 0/C.

Three-dimensional radiography with thermal neutrons is described. The laminagraphic method is shown to provide a spatial resolution better than 1 mm for complex objects as thick as 50 mm.

The Los Alamos Scientific Laboratory is a large, multidisciplined research laboratory, operated by the University of California for the U.S. Energy Research and Development Administration. An interactive graphic system was developed to integrate design, drafting, testing, analysis, and manufacturing to achieve efficient and effective laboratory-wide services. To accomplish this, the graphic system is hardware independent, and has an associative data base structured on two- and three-dimensional, bounded geometry. The data base allows for levels of attributes that can be attached or deleted and interrogated. This graphic system is described, with emphasis on the efficiencies of graphics and the effect of the associative data base on the ''design--build--test'' cycle. The capability of attaching attributes is explored as the means of bridging the CAD/CAM gap.

We built a multimedia document system for the SIGGRAPH Interactive Proceedings to demonstrate the potentials and challenges in using technology to capture better the essence of SIGGRAPH conferences. The prototype system uses the NeXT computer system to present textual, mathematical, illustrative, colorful, audio, video and animated material. Special attention was given to including tools for interactive manipulation of images included in typical SIGGRAPH papers. 6 refs., 6 figs.

A summary is given of the atomic physics concerned with plasma cooling by impurities and the limiting effect that impurities may have on heating of plasmas by neutral injection. A general description is given of the tokamak concept and the present and next generation experiments are described. The time and spatial behavior of O and Mo multicharged ions in present hydrogen plasmas is presented. This is followed by a discussion of the power loss from a plasma containing one percent Fe. Finally, the limitation of plasma heating by energetic H or D injection is summarized. (MOW)

This paper summarizes results of the Los Alamos theta-pinch program in three areas of investigation. (1) In the Staged Theta Pinch results are reported on the effects of magnetic field amplitude and time history of plasma formation. (2) In the Implosion Heating Experiment density, internal-magnetic-field and neutron measurements yield a consistent picture of the implosion which agrees with kinetic computations and with a simple dynamic model of the ions and magnetic piston. (3) In the Scyllac Feedback-Sector Experiment the l = 1, 0 equilibrium plasma parameters have been adjusted to accommodate the feedback stabilization system. With a uniform toroidal discharge tube the m = 1 instability is feedback-stabilized in the vertical direction, and confinement in the toroidal direction is extended by feedback control. We also report results with a helical discharge tube.

Current design of the Clinch River Breeder Reactor (CRBR) calls for the at-power flux monitors to be located outside the reactor vessel some 330 cm from the center of the core. This design uses these same detectors for the monitoring of refueling operations and the subsequent approach to power. Although adequate for at-power operation, these monitors could prove marginal in the shutdown mode (so called low level flux monitors). A series of experiments are to be performed on the CRBR engineering mockup (ZPPR-5) to test the ex-vessel monitors. The matrix design limits the distance from the core center to the detector position to approximately 200 cm. Hence, the full 330 cm from the core center to the LLFM can not be mocked up in the ZPPR-5 assembly. An attempt was made to design a spectral modifier which would result in the same source and absorber detector response as found in the CRBR design. This was accomplished using the source and adjoint fluxes obtained from a one-dimensional ANISN calculation. The results of examinations of several materials are presented.

A summary is given of theoretical results concerning line-shape in the presence of non-stationary perturbations, and of the polarization of radiation emitted by a nucleus influenced by time-dependent fields.

The overall objective of the current Task 6 under Contract AC21-90MC27168 is to develop understanding as well as quantification of cell ohmic resistance in carbonate fuel cell. The important resistance-contributing interfaces and elements are being investigated in high-temperature out-of-cell resistance experiments, using an AC-impedance technique. Ohmic resistance loss in a state-of-the-art carbonate fuel cell contributes about 65 mV loss at BOL (beginning-of-life). It may increase to about as much as 145 mV after 40,000 hours. Its reduction will offer further improvement in fuel cell power plant efficiency. The important resistance contributing elements/interfaces are illustrated in Figure 1. The majority of the ohmic loss attributed to electrolyte matrix (ionic) and cathode-side hardware (electronic). The ohmic loss due to anode-side hardware can generally be neglected because the anode-side hardware is surface protected resulting in very little surface oxide formation. The ohmic resistance of the electrodes is also negligible. The matrix ionic resistance is influenced by many factors: electrolyte conductivity, matrix porosity, tortuosity, electrolyte fill level and matrix thickness. At present, matrix contributes to > 300 m{Omega}cm{sup 2} (>70% of the total cell ohmic resistance) and is the major resistance contributor.

ISOCELL{sup TM} cryogenic technology is designed to immobilize buried hazardous, radioactive, and mixed waste and contaminated soil by creating a block of frozen waste and soil that can be safely retrieved, stored, transported, and treated with a minimum of dust or aerosol production. A proof-of-concept'' test of the ISOCELL process was conducted in clean soil by RKK, Ltd., for the Idaho National Engineering Laboratory (INEL). Results indicate ISOCELL technology successfully froze moist soil into a solid block capable of being lifted and retrieved. Test conditions were compared to characteristics of possible buried waste sites in the INEL.

Methods are described for monitoring work areas for the presence of primary amines and chemicals readily transformable to primary amines that are potentially carcinogenic. Chemical spot tests for surface monitoring are described and their capabilities and limitations are discussed for monitoring work areas, equipment, and respirators after use in hazardous environments. Methods for work area and personnel decontamination are also described. A list of cancer-suspect amines is included. (CH)

Data are presented that describe the variability of 15 products of a reference heat of type 304 stainless steel tested in the laboratory reannealed condition: chemistry hardness, grain size, yield strength at room temperature, tensile curves at 593/sup 0/C (1100/sup 0/F), and creep-rupture curves to 1000 h at 593/sup 0/C (1100/sup 0/F). The standard deviation, representing the variation in the yield strength of the 15 products about the average, is near+-l.7 MPa at room temperature and +-6.3 MPa at 593/sup 0/C (1100/sup 0/F). The 1000-h rupture strength varies by 2.5 percent (approximately +-6.2 MPa) from the average and the stress to produce a minimum creep rate of 0.01 percent/h by 3.0 percent (approximately +-5.0 MPa). Variation of strength in the primary creep range is also examined. It is observed that the 25-mm plate is fairly representative of the product average. Reasons for variability are examined: carbon content, nitrogen content, grain size, temperature control, and extensometer performance. 7 tables, 5 figures.

During the past 25 years, a rather rapid evolution has taken place in the design and use of prestressed concrete reactor vessels (PCRVs). Initially the concrete vessel served as a one-to-one replacement for its steel counterpart. This was followed by the development of the integral design which led eventually to the more recent multicavity vessel concept. Although this evolution has seen problems in construction and operation, a state-of-the-art review which was recently conducted by the Oak Ridge National Laboratory indicated that the PCRV has proven to be a satisfactory and inherently safe type of vessel for containment of gas-cooled reactors from a purely functional standpoint. However, functionalism is not the only consideration in a demanding and highly competitive industry. A summary is presented of the important considerations in the design and analysis of multicavity PCRVs together with overall conclusions concerning the state of the art of these vessels.

The drilling of wells comprises a large fraction of the costs of geothermal energy-extraction plants, and billions of dollars for wells will be needed before geothermal energy is nationally significant. Technical and cost studies were made of the application of the Subterrene concept, i.e., excavating and penetrating rocks or soils by melting, to deep wells such as may be used for dry-hot-rock or geopressure geothermal energy extraction systems. Technically, it was found that Subterrene requirements are compatible with those of current rotary drilling practices. Certain features of the rock-melting concept such as the glass lining on the borehole wall, and nonrotation, provide opportunities for the development of better well production techniques in hot wells. A typical optimum-cost well would be rotary-drilled in the upper regions and then rock-melted to total depth. Indicated cost-savings are significant: a 33 percent or 4.5 million dollars reduction from rotary drilled well costs are estimated for a 10 km depth well with bottom hole temperatures of 673 K. Even for normal geothermal gradient conditions, the savings for the 10 km depth is estimated as 23 percent or 2 million dollars.

Many theoretical models have been employed to described the structure of the nucleus {sup 24}Mg. Among these are the Cranked Shell model (CSM), the Cranked Cluster Model (CCM), and calculations have also been performed using the Hartree-Fock formalism. One very striking prediction of these calculations is that in this nucleus there exist very unusual configurations, with structures reminiscent of linear chains of alpha particles. In the CSM, for instance, such a configuration is identified with a pronounced minimum in the potential energy energy at very large prolate deformation. In the CCM, several very different alpha-particle duster configurations are identified, many having rather large deformations. These cluster configurations can be associated with the different potential-energy minima obtained in the CSM results. In the case of the CCM, a 6{alpha} chain-like configuration is predicted to occur at excitation energies between 40 and 50 MeV, with predicted rotational spacing given by {Dirac h}{sup 2}/2I=22 keV. At this excitation energy, such a chain configuration would lie well above the threshold for the decay of {sup 24}Mg into 6 alpha particles, and its identification poses a difficult experimental challenge. This report discusses this challenge.

A study has been conducted on the recent progress of the three-terminal devices with transistor-like characteristics fabricated from the high-{Tc} superconducting materials. This study explored the operating principles and characteristics of these devices in relation to the relevant materials and techniques. A comparison of a variety of techniques for superconducting thin film deposition will be given. This study indirates that the feasibility of fabricating hybrid devices composed of semiconductors and superconductors appear to be the key issue to push forward the applications of high-{Tc} superconductors in microelectronics. The junction field-effect transistors with a semiconductor base controlled by the proximity effect are likely to be more manufacturable. The factors that influence the operating reliability of devices and the problems arising from integrating and packaging the devices will also be discussed.