Tritium containment and removal problems in a fuel-reprocessing plant are identified and conceptual process designs for reducing emissions to the environment to below 1 Ci/day are studied. The conceptual design recommended would allow an air atmosphere in the reprocessing-plant hall and would use a continuous-catalytic-oxidizer/molecular-sieve-adsorber cleanup system to maintain a 40-..mu..Ci/m/sup 3/ tritium level (5 ..mu..Ci/m/sup 3/ HTO) against 180 Ci/day leakage from components and process piping.

While other programs check for bad passwords after the fact, it in important to have good passwords at all times, not just after the latest Crack run. To this end we have modified Larry Wall's Perl password program and added, among other features, the ability to check a sorted list of all the bad passwords'' that Crack will generate, given all the dictionaries that we could get our hands on (107 MB of unique words, so far). The combination of improvements has turned publicly available code into a powerful tool that can aid sites in the maintenance of local security.

Two ''plugs'' of dense plasma at either end of a central solenoid cell form the basis of a new mirror fusion power plant concept. A central cell blanket design is presented. Modules on crawler tracks serviced by remote welding and handling machines of very simple design are important features resulting from linear axisymmetric geometry. Three blanket designs are considered and the best one presented in some detail. It has lithium as the breeder material, helium cooled. ''Plug'' magnet field strengths must be high. A novel magnet is presented to satisfy the physics of the end plugs. Beam sources at 1,200 KV present special problems. Methods of voltage standoff, arc damage control, and neutralization are discussed. New secondary containment ideas are presented to allow removable roof sections of balanced design.

Vacuum pumping by freezing out or otherwise immobilizing the pumped gas is an old concept. In several plasma physics experiments for controlled fusion research, cryopumping has been used to provide clean, ultrahigh vacua. Present day fusion research devices, which rely almost universally upon neutral beams for heating, are high gas throughput systems, the pumping of which is best accomplished by cryopumping in the high mass-flow, moderate-to-high vacuum regime. Cryopumping systems have been developed for neutral beam injection systems on several fusion experiments (HVTS, TFTR) and are being developed for the overall pumping of a large, high-throughput mirror containment experiment (MFTF). In operation, these large cryopumps will require periodic defrosting, some schemes for which are discussed, along with other operational considerations. The development of cryopumps for fusion reactors is begun with the TFTR and MFTF systems. Likely paths for necessary further development for power-producing reactors are also discussed.

A scenario for the central engine of AGN has been developed consisting of a massive black hole (MBH) onto which gas accretes through an accretion disk. The accretion disk radiates the observed optical and ultraviolet continua. Surrounding the MBH is a nonthermal source which produces the infrared and soft x-ray continua by synchrotron emission, and the x-ray spectrum by inverse Compton scattering of the optical-ultraviolet photons from the accretion disk. Previously we modeled the accretion disk (M.A.M.) and nonthermal source (D.L.B.) separately, and here we combine the two models to form a unified description of the AGN engine. This combined model can be inverted to determine source parameters from observed spectra. A group of AGN for which multiband observations exist can then be modeled to: demonstrate the validity of the combined model for a large number of objects; establish the range of parameter values that describe the source; and search for any correlations between source description and type.

Tritium-containment systems for the blanket and power systems of a mirror-fusion reactor are described. These systems are designed to reduce emissions to below 1 Ci/d. The overall conceptual design uses air as the reactor-hall atmosphere. A continuous catalytic oxidizer-molecular sieve adsorber cleanup system would be used to control a 180-Ci/d leakage from reactor components, energy recovery systems, and process piping. Such a system would maintain a 40 ..mu..Ci/m/sup 3/ tritium level (5 ..mu..Ci/m/sup 3/ HTO) in the hall. The blanket considered contains submodules with Li/sub 2/Be/sub 2/O/sub 3/-Be for tritium breeding. This canned breeding material is scavenged with a lithium-vapor-doped helium gas stream. The container consists of molybdenum alloy (TZM) tubes and tube sheets with the breeding material packed and sintered in the shell surrounding the tubes. Potassium vapor coolant (also lithium-doped) passes through these tubes to recover the heat at 950/sup 0/C. Leakage following an intermediate TZM exchanger would result in a loss of 0.7 Ci/d into the steam through the Haynes-25 alloy boiler (potassium boiling). A moving getter bed is used to recover the tritium from the LiT and Li/sub 2/T scavengers in both the helium blanket scavenging flow and the potassium vapor coolant.

Space charge as it affects ion beam transport is reviewed. The approach here will be to derive beam-current criteria for divergence from space charge, review recent theoretical models for fractional space-charge neutralization, discuss space-charge-related observations on ion-beam transport in a specific experimental system, and briefly note several applications using space charge. Experimental measurements of effective space charge are discussed for a dc ion-source test stand using a 90/sup 0/ double-focusing magnet for species separation and for a solenoidal lens magnet for trim focus of the ion beam preparatory to entrance into a 400-kV accelerator column.

Fluids from various formations were sampled and analyzed in order to characterize groundwaters in the Delaware Basin. Waters were analyzed for solute content and/or stable isotope ratios (D/H and /sup 18/O//sup 16/O). Three lines of geochemical arguments are summarized, in order to present the natures and probable origins of analyzed fluids: solute chemistry, thermodynamic modelling of low-temperature aqueous species, and stable isotope ratios. (JGB)

Methods used to control the radiological impact of the nuclear fuel cycle are described. This control is exercised through the application of a series of federal laws and regulations that are used as the basis for licensing nuclear facilities. The control is exercised more directly by the use of radwaste treatment equipment at the nuclear facilities to limit the release of radioactive materials. Federal laws and regulations are summarized and their applications in licensing actions are discussed. Radiological doses from materials released from licensed facilities are compared with doses from natural background. A series of cost/benefit engineering surveys are being made to determine the cost and effectiveness of radwaste systems for decreasing the release of radioactive materials from model fuel cycle facilities and to determine the benefits in terms of reduction in dose commitment to individuals and populations in surrounding areas.

The principles of mirror machine confinement are reviewed with emphasis on the physical process of neutral beam injection and plasma end leakage. The characteristics of efficient neutral beam injectors and direct energy convertors for the plasma and leakage are described.

Radiation blistering in solids has been identified as a process leading to damage and erosion of irradiated surfaces. Some of the major parameters governing the blistering process in metals and some metallic alloys are the type of projectile and its energy, total dose, dose rate, target temperature, channeling condition of the projectile, orientation of the irradiated surface plane, and target material and its microstructure. Experimental results and models proposed for blister formation and rupture are reviewed. The blistering phenomenon is important as an erosion process in applications such as fusion reactor technology (plasma-wall interactions) and accelerator technology (erosion of components and targets). A description of methods for the reduction of surface erosion caused by blistering is included.

A review is made of the current status of /sup 235/U fission cross section data from thermal to 20 MeV neutron energies. The accuracy achieved is compared with the 1 percent accuracy required of a reaction-cross-section standard throughout this range. The energy ranges from thermal to 10 keV, 10 keV to 0.8 MeV and 0.8 to 20 MeV are considered separately because of the different experimental techniques required in each. The goal of normalizing all fission cross sections to the thermal value and the current degree of success is discussed.

''Obfuscatory measurement'' is the practice, deliberate or not, of obscuring the true performance of a system through the use of misleading measures. Many of the traditional and widely used measures of computer system performance are obfuscatory: they measure the wrong things, the right things wrongly, or nothing at all. Several obfuscatory measures are considered; those aspects of the system they are thought to measure are contrasted with those that they actually measure; and alternative measures, which are more meaningful to the user community, are suggested. 3 figures, 1 table.

In order for computation to emerge spontaneously and become an important factor in the dynamics of a system, the material substrate must support the primitive functions required for computation: the transmission, storage, and modification of information. Under what conditions might we expect physical systems to support such computational primitives This paper presents research on Cellular Automata which suggests that the optimal conditions for the support of information transmission, storage, and modification, are achieved in the vicinity of a phase transition. We observe surprising similarities between the behaviors of computations and systems near phase-transitions, finding analogs of computational complexity classes and the Halting problem within the phenomenology of phase-transitions. We conclude that there is a fundamental connection between computation and phase-transitions, and discuss some of the implications for our understanding of nature if such a connection is borne out. 31 refs., 16 figs.

Solid state experiments at extreme pressures (10-100 GPa) and strain rates ({approx}10{sup 6}-10{sup 8}s{sup -1}) are being developed on high-energy laser facilities, and offer the possibility for exploring new regimes of materials science. [Re 2004] These extreme solid-state conditions can be accessed with either shock loading or with quasi-isentropic ramped pressure pulses being developed on the Omega laser. [Ed 2004] Velocity interferometer measurements establish the high strain rates. Constitutive models for solid-state strength under these conditions are tested by comparing 2D continuum simulations with experiments measuring perturbation growth due to the Rayleigh-Taylor instability in solid-state samples. Lattice compression, phase, and temperature are deduced from extended x-ray absorption fine structure (EXAFS) measurements, from which the shock-induced a-w phase transition in Ti is inferred to occur on sub-nanosecond time scales. [Ya 2004] Time resolved lattice response and phase can be inferred from dynamic x-ray diffraction measurements, where the elastic-plastic (1D-3D) lattice relaxation in shocked Cu is shown to occur promptly (< 1 ns). [Lo 2003] Subsequent large-scale MD simulations have elucidated the microscopic dynamics that underlie the 3D lattice relaxation. Deformation mechanisms are identified by examining the residual microstructure in recovered samples. [Re 2004] For example, the slip-twinning threshold in single-crystal Cu …

Fast intermittent transport has been observed in the scrape-off layer (SOL) of major tokamaks including Alcator C-Mod, DIII-D, and NSTX. This kind of transport is not diffusive but rather convective. It strongly increases plasma flux to the chamber walls and enhances the recycling of neutral particles in the main chamber. We discuss anomalous cross-field convection (ACFC) model for impurity and main plasma ions and its relation to intermittent transport events, i.e. plasma density blobs and holes in the SOL. Along with plasma diffusivity coefficients, our transport model introduces time-independent anomalous cross-field convective velocity. In the discharge modelling, diffusivity coefficients and ACFC velocity profiles are adjusted to match a set of representative experimental data. We use this model in the edge plasma physics code UEDGE to simulate the multi-fluid two-dimensional transport for these three tokamaks. We present simulation results suggesting the dominance of anomalous convection in the far SOL transport. These results are consistent with the hypothesis that the chamber wall is an important source of impurities and that different impurity charge states have different directions of anomalous convective velocity.

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A technique is developed to construct bulk hydroxyapatite (HAp) with different cellular structures. The technique involves the initial synthesis of nanocrystalline hydroxyapatite powder from an aqueous solution using water-soluble compounds and then followed by spray drying into agglomerated granules. The granules were further cold pressed and sintered into bulks at elevated temperatures. The sintering behavior of the HAp granules was characterized and compared with those previously reported. Resulting from the fact that the starting HAp powders were extremely fine, a relatively low activation energy for sintering was obtained. In the present study, both porous and dense structures were produced by varying powder morphology and sintering parameters. Porous structures consisting of open cells were constructed. Sintered structures were characterized using scanning electron microscopy and x-ray tomography. In the present paper, hydroxyapatite coatings produced by magnetron sputtering on silicon and titanium substrates will also be presented. The mechanical properties of the coatings were measured using nanoindentation techniques and microstructures examined using transmission electron microscopy.

First-principles generalized pseudopotential theory (GPT) provides a fundamental basis for transferable multi-ion interatomic potentials in transition metals and alloys within density-functional quantum mechanics. In central bcc transition metals, where multi-ion angular forces are important to structural properties, simplified model GPT or MGPT potentials have been developed based on canonical d bands to allow analytic forms and large-scale atomistic simulations. Robust, advanced-generation MGPT potentials have now been obtained for Ta and Mo and successfully applied to a wide range of structural, thermodynamic, defect and mechanical properties at both ambient and extreme conditions. Selected applications to multiscale modeling discussed here include dislocation core structure and mobility, atomistically informed dislocation dynamics simulations of plasticity, and thermoelasticity and high-pressure strength modeling. Recent algorithm improvements have provided a more general matrix representation of MGPT beyond canonical bands, allowing improved accuracy and extension to f-electron actinide metals, an order of magnitude increase in computational speed for dynamic simulations, and the still-in-progress development of temperature-dependent potentials.

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Plasma confinement and neutral beam injection heating were investigated on the Oak Ridge Tokamak (ORMAK) plasma with improved plasma parameters due to higher injection power (to 360 kW), discharge current (to 220 kA) and toroidal field (to 26 kG). With increasing injection power up to 360 kW with otherwise constant operational parameters, the central ion temperature increased roughly linearly from 0.7 keV to 1.8 keV. The scaling of ion temperature with injection power and plasma density reasonably agrees with theoretical predictions based on neoclassical ion heat conduction and classical beam energy transport.

The objective of the ''Local Integration of the National Atmospheric Release Advisory Center with Cities'' (LINC) program is to demonstrate the capability for providing local government agencies with an advanced operational atmospheric plume prediction capability, which can be seamlessly integrated with appropriate federal agency support for homeland security applications. LINC is a Domestic Demonstration and Application Program (DDAP) funded by the Chemical and Biological National Security Program (CBNP), which is part of the Department of Energy's (DOE) National Nuclear Security Administration (NNSA). LINC will make use of capabilities that have been developed the CBNP, and integrated into the National Atmospheric Release Advisory Center (NARAC) at Lawrence Livermore National Laboratory (LLNL). NARAC tools services will be provided to pilot study cities and counties to map plumes from terrorism threats. Support to these local agencies will include training and customized support for exercises, special events, and general emergencies. NARAC provides tools and services that map the probable spread of hazardous material which have been accidentally or intentionally released into the atmosphere. Primarily supported by the DOE, NARAC is a national support and resource center for planning, real-time assessment and detailed studies of incidents involving a wide variety of hazards, including radiological, chemical, …

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Soils beneath and adjacent to the Pavlodar Chemical Plant in Kazakhstan have been contaminated with elemental mercury as a result of chlor alkali processing using mercury cathode cell technology. The work described in this paper was conducted in preparation for a demonstration of a technology to remove the mercury from the contaminated soils using a vacuum assisted thermal distillation process. The process can operate at temperatures from 250-500 C and pressures of 0.13kPa-1.33kPa. Following vaporization, the mercury vapor is cooled, condensed and concentrated back to liquid elemental mercury. It will then be treated using the Sulfur Polymer Stabilization/Solidification process developed at Brookhaven National Laboratory as described in a companion paper at this conference. The overall project objectives include chemical and physical characterization of the contaminated soils, study of the influence of the soil's physical-chemical and hydro dynamical characteristics on process parameters, and laboratory testing to optimize the mercury sublimation rate when heating in vacuum. Based on these laboratory and pilot-scale data, a full-scale production process will be designed for testing. This paper describes the soil characterization. This work is being sponsored by the International Science and Technology Center.