OAK A271 ADVANCED HIGH PERFORMANCE SOLID WALL BLANKET CONCEPTS. First wall and blanket (FW/blanket) design is a crucial element in the performance and acceptance of a fusion power plant. High temperature structural and breeding materials are needed for high thermal performance. A suitable combination of structural design with the selected materials is necessary for D-T fuel sufficiency. Whenever possible, low afterheat, low chemical reactivity and low activation materials are desired to achieve passive safety and minimize the amount of high-level waste. Of course the selected fusion FW/blanket design will have to match the operational scenarios of high performance plasma. The key characteristics of eight advanced high performance FW/blanket concepts are presented in this paper. Design configurations, performance characteristics, unique advantages and issues are summarized. All reviewed designs can satisfy most of the necessary design goals. For further development, in concert with the advancement in plasma control and scrape off layer physics, additional emphasis will be needed in the areas of first wall coating material selection, design of plasma stabilization coils, consideration of reactor startup and transient events. To validate the projected performance of the advanced FW/blanket concepts the critical element is the need for 14 MeV neutron irradiation facilities for …

This project deals with the modeling the Aerial Measuring System (AMS) fixed-wing and rotary-wing sensor systems, which are critical U.S. Department of Energy's National Nuclear Security Administration (NNSA) Consequence Management assets. The fixed-wing system is critical in detecting lost or stolen radiography or medical sources, or mixed fission products as from a commercial power plant release at high flying altitudes. The helicopter is typically used at lower altitudes to determine ground contamination, such as in measuring americium from a plutonium ground dispersal during a cleanup. Since the sensitivity of these instruments as a function of altitude is crucial in estimating detection limits of various ground contaminations and necessary count times, a characterization of their sensitivity as a function of altitude and energy is needed. Experimental data at altitude as well as laboratory benchmarks is important to insure that the strong effects of air attenuation are modeled correctly. The modeling presented here is the first attempt at such a characterization of the equipment for flying altitudes. The sodium iodide (NaI) sensors utilized with these systems were characterized using the Monte Carlo N-Particle code (MCNP) developed at Los Alamos National Laboratory. For the fixed wing system, calculations modeled the spectral response for …

Calculations were performed using MOCUP, which includes the use of MCNP for neutron transport and ORIGEN for depletion. The MOCUP calculations were done using a unit cell (pin cell) model, where the ThO2 varied from 65-75wt% and the UO2 varied from 25-35wt%. The fission products and actinides being tracked in the calculations account for >97% of the parasitic captures in the fuel. The fuel pin was surrounded by four reflecting planes, where typical parameters were used for a 17x17 PWR assembly. The hydrogen to heavy metal ratio (H/HM) was varied by increasing or decreasing the water density in the cell. The results show that the drier lattices have insufficient reactivity due to the limited enrichment of the uranium. However, a slightly wetter lattice will increase the reactivity-limited burnup by 26% for the 25% UO2 – 75% ThO2, and 19% for the 35% UO2 – 65% ThO2 as compared to the standard coolant density. This is appears to be consistent with similar studies done with all-uranium lattices, where advantages are gained by hardening or further softening the neutron spectrum. Although some advantage is gained by softening the spectrum, the same can be said of all-uranium fueled cores. The spectral changes and, …

In addressing the goals of energy-efficiency and indoor air quality (IAQ) in homes, industry teams in the U.S. Department of Energy's Building America program are installing mechanical ventilation systems in tight homes.

Article on biochemical and molecular inhibition of plastidial carbonic anhydrase reducing the incorporation of acetate into lipids in cotton embryos and tobacco cell suspensions and leaves.

An article, written by Lou Chibbaro Jr. for the Washington Blade, about the new group of advisors who will be tackling the HIV/AIDS issue with President George W. Bush. The article lists out the new members and also points to supporters and raises concerns that some have over what the group's outcome will be.

OAK A271 COATING AND MANDREL EFFECTS ON FABRICATION OF GLOW DISCHARGE POLYMER NIF SCALE INDIRECT DRIVE CAPSULES. Targets for the National Ignition Facility (NIF) need to be about 200 {micro}m thick and 2 mm in diameter. These dimensions are well beyond those currently fabricated on a routine basis. They have investigated fabrication of near NIF scale targets using the depolymerizable mandrel technique. Poly-alpha-methylstyrene (PAMS) mandrels, about 2 mm in diameter, of varying qualities were coated with as much as 125 {micro}m of glow discharge polymer (GDP). The surface finish of the final shells was examined using a variety of techniques. A clear dependence of the modal spectrum of final GDP shell on the quality of the initial PAMS mandrels was observed. isolated features were found to be the greatest cause for a shell not meeting the NIF standard.

OAK A271 COMPOSITION AND STRUCTURAL STUDIES OF STRONG GLOW DISCHARGE POLYMER COATINGS. An investigation of the chemical composition and structure of strong glow discharge (GDP) polymer shells made for cryogenic experiments at OMEGA is described. The investigation was carried out using combustion and Fourier Transform Infrared Spectroscopy (FTIR) analysis. The strongest coatings were observed to have the lowest hydrogen content or hydrogen/carbon H/C ratio, whereas the weakest coatings had the highest hydrogen content or H/C ratio. Chemical composition results from combustion were used to complement FTIR analysis to determine the relative hydrogen content of as-fabricated coatings. Good agreement was observed between composition results obtained from combustion and FTIR analysis. FTIR analysis of coating structures showed the strongest coatings to have less terminal methyl groups and a more double bond or olefinic structure. Strong GDP coatings that were aged in air react more with oxygen and moisture than standard GDP coatings. In addition to a more olefinic structure, there may also be more free-radial sites present in strong GDP coatings, which leads to greater oxygen uptake.

The role of moduli stabilization in predictions for CP violation is examined in the context of four-dimensional effective supergravity models obtained from the weakly coupled heterotic string. They point out that while stabilization of compactification moduli has been studied extensively, the determination of background values for other scalar by dynamical means has not been subjected to the same degree of scrutiny. These other complex scalars are important potential sources of CP violation and they show in a simple model how their background values (including complex phases) may be determined from the minimization of the supergravity scalar potential, subject to the constraint of vanishing cosmological constant.

Describes the creep behavior of three Sn-rich solders that have become candidates for use in Pb-free solder joints: Sn-3.5Ag, Sn-3Ag-0.5Cu and Sn-0.7Cu. The three solders show the same general behavior when tested in thin joints between Cu and Ni/Au metallized pads at temperatures between 60 and 130 C. Their steady-state creep rates are separated into two regimes with different stress exponents(n). The low-stress exponents range from {approx}3-6, while the high-stress exponents are anomalously high (7-12). Strikingly, the high-stress exponent has a strong temperature dependence near room temperature, increasing significantly as the temperature drops from 95 to 60 C. The anomalous creep behavior of the solders appears to be due to the dominant Sn constituent. Joints of pure Sn have stress exponents, n, that change with stress and temperature almost exactly like those of the Sn-rich solder joints. Research on creep in bulk samples of pure Sn suggests that the anomalous temperature dependence of the stress exponent may show a change in the dominant mechanism of creep. Whatever its source, it has the consequence that conventional constitutive relations for steady-state creep must be used with caution in treating Sn-rich solder joints, and qualification tests that are intended to verify performance should …

We review recent developments in the study of deep inelastic scattering from light nuclei, focusing in particular on deuterium, helium, and lithium nuclei. Understanding the nuclear effects in these systems is essential for the extraction of information on the neutron structure function.

The SCDAP-3D computer code (Coryell 2001) has been developed at the Idaho National Engineering and Environmental Laboratory (INEEL) for the analysis of severe reactor accidents. A prominent feature of SCDAP-3D relative to other versions of the code is its linkage to the state-of-the-art thermal/hydraulic analysis capabilities of RELAP5-3D. Enhancements to the severe accident models include the ability to simulate high burnup and alternative fuel, as well as modifications to support advanced reactor analyses, such as those described by the Department of Energy's Generation IV (GenIV) initiative. Initial development of SCDAP-3D is complete and two widely varying but successful applications of the code are summarized. The first application is to large break loss of coolant accident analysis performed for a reactor with alternative fuel, and the second is a calculation of International Standard Problem 45 (ISP-45) or the QUENCH 6 experiment.

The stability of tungsten carbide particles in iron-rich and nickel-rich liquid during the laser surface alloying (LSA) process was investigated. Kinetic calculations indicate a rapid dissolution of tungsten carbide particles in iron-rich liquid, as compared with the dissolution rate in nickel-rich liquid. Optical microscopy indicated a heterogeneous microstructure around the tungsten particles that is in agreement with concentration gradients predicted by kinetic calculation. The work demonstrates the applicability of computational thermodynamics and kinetic models for the LSA process.

The California Climate Action Registry, which will begin operation in Fall 2002, is a voluntary registry for California businesses and organizations to record annual greenhouse gas emissions. Reporting of emissions in the Registry by a participant involves documentation of both ''direct'' emissions from sources that are under the entity's control and ''indirect'' emissions controlled by others. Electricity generated by an off-site power source is considered to be an indirect emission and must be included in the entity's report. Published electricity emissions factors for the State of California vary considerably due to differences in whether utility-owned out-of-state generation, non-utility generation, and electricity imports from other states are included. This paper describes the development of three methods for estimating electricity emissions factors for calculating the combined net carbon dioxide emissions from all generating facilities that provide electricity to Californians. We fi nd that use of a statewide average electricity emissions factor could drastically under- or over-estimate an entity's emissions due to the differences in generating resources among the utility service areas and seasonal variations. In addition, differentiating between marginal and average emissions is essential to accurately estimate the carbon dioxide savings from reducing electricity use. Results of this work will be taken …

We present experimental results of dopant- and self-diffusion in extrinsic silicon doped with As. Multilayers of isotopically controlled {sup 28}Si and natural silicon enable simultaneous analysis of {sup 30}Si diffusion into the {sup 28}Si enriched layers and dopant diffusion throughout the multilayer structure. In order to suppress transient enhanced self- and dopant diffusion caused by ion implantation, we adopted a special approach to dopant introduction. First, an amorphous 250-nm thick Si layer was deposited on top of the Si isotope heterostructure. Then the dopant ions were implanted to a depth such that all the radiation damage resided inside this amorphous cap layer. These samples were annealed for various times and temperatures to study the impact of As diffusion and doping on Si self-diffusion. The Si self-diffusion coefficient and the dopant diffusivity for various extrinsic n-type conditions were determined over a wide temperature range. We observed increased diffusivities that we attribute to the increase in the concentration of the native defect promoting the diffusion.

The extended Born, or localized nonlinear (LN) approximation, of integral equation (IE) solution has been applied to inverting single-hole electromagnetic (EM) data using a cylindrically symmetric model. The extended Born approximation is less accurate than a full solution but much superior to the simple Born approximation. When applied to the cylindrically symmetric model with a vertical magnetic dipole source, however, the accuracy of the extended Born approximation is shown to be greatly improved because the electric field is scalar and continuous everywhere. One of the most important steps in the inversion is the selection of a proper regularization parameter for stability. The extended Born solution provides an efficient means for selecting an optimum regularization parameter, because the Green's functions, the most time consuming part in IE methods, are repeatedly re-usable at each iteration. In addition, the IE formulation readily contains a sensitivity matrix, which can be revised at each iteration at little expense. In this paper we show inversion results using synthetic and field data. The result from field data is compared with that of a 3-D inversion scheme.

The evaluation of a release of radioactive material to the environment is a complex problem. The evaluation of the dose consequences from such a release adds issues that must be considered in order to determine the actual radiation dose to an individual. One of the key issues is the ingrowth of the progeny from the initial inventory during the transport through the environment. The evaluation of an acute release from a criticality accident and a chronic release of transuranics to the soil are the two extremes that demonstrate the spectrum of issues that must be addressed in order to determine the dose to a receptor at some distance and time from the release point. The evaluation of this can be accomplished by integration of the buildup and decay differential equations. The differential equations are difficult to evaluate for a source term that contains numerous short-lived radionuclides in decay chains. The evaluation is simplified by a method of evaluation called "counting atom". The source term is evaluated on an atom basis during production and transport. The life cycle of the atoms of each radionuclide are evaluated individually from the generation during a criticality event and during transport through the facility and …

N* masses in the spin-1/2 and spin-3/2 sectors are computed using two non-perturbative methods: lattice QCD and QCD sum rules. States with both positive and negative parity are isolated via parity projection methods. The basic pattern of the mass splittings is consistent with experiments. The mass splitting within the same parity pair is directly linked to the chiral symmetry breaking QCD.

The Idaho National Engineering and Environmental Laboratory (INEEL), Nexant Inc. and the Oregon State University (OSU) have developed a Multi-Application Small Light Water Reactor (MASLWR) concept. The MASLWR is a small, safe and economic natural circulation pressurized light water reactor. MASLWR reactor module consists of an integral reactor/steam generator located in a steel cylindrical containment. The entire module is to be entirely shop fabricated and transported to site on most railways or roads. Two or more modules are located in a reactor building, each being submersed in a common, below grade cavity filled with water. For the most severe postulated accident, the volume of water in the cavity provides a passive ultimate heat sink for 3 or more days allowing the restoration of lost normal active heat removal systems. MASLWR thermal power of a single module is 150 MWt, primary system pressure 10.5 MPa, steam pressure1.52 MPa and the net electrical output is 35 - 50 MWe.

A major feature of the Magnox gas cooled reactor design is the graphite core, which acts as the moderator but also provides the physical structure for fuel, control rods, instrumentation and coolant gas channels. The lifetime of a graphite core is dependent upon two principal aging processes: irradiation damage and radiolytic oxidation. Irradiation damage from fast neutrons creates lattice defects leading to changes in physical and mechanical properties and the accumulation of stresses. Radiolytic oxidation is caused by the reaction of oxidizing species from the carbon dioxide coolant gas with the graphite, these species being produced by gamma radiation. Radiolytic oxidation reduces the density and hence the moderating capability of the graphite, but also reduces strength affecting the integrity of core components. In order to manage continued operation over the planned lifetimes of their power stations, BNFL needed to extend their database of the effects of these two phenomena on their graphite cores through an irradiation experiment. This paper will discuss the background, purpose, and the processes taken and planned (i.e. post irradiation examination) to ensure meaningful data on the graphite core material is obtained from the irradiation experiment.

An introductory review of generalized parton distributions (GPDs) is given. The structure of hadrons is the fundamental physics to be accessed via GPDs. GPDs describe hadronic structure on the quark-gluon level and provide a 3-dimensional picture (''tomography'') of hadronic structure. GPDs adequately reflect the quantum-field nature of QCD (correlations, interference). They also provide new insights into spin structure of hadrons (spin-flip distributions, orbital angular momentum). GPDs are sensitive to chiral symmetry breaking effects, a fundamental property of QCD. Furthermore, GPDs unify existing ways of describing hadronic structure. The GPD formalism provides nontrivial relations between different exclusive reactions and also between exclusive and inclusive processes.

A new generation of experiments for studies of the nucleon structure with electromagnetic probes is under consideration by the physics community interested in hadron physics. One of the main goals of these projects is studying the Generalized Parton Distributions (GPD), which typically requires detecting several particles in the final state, high luminosity, large acceptance and good missing mass resolution of the spectrometers. The combination of these requirements is challenging and pushes the detectors involved to the limits. In this paper a review of the proposed experiments is presented and their feasibility is evaluated taking into account the recent progress of the detector technique.

Although robotic machines are routinely used for welding, such machines do not normally incorporate intelligent capabilities. We are studying the general problem of formulating usable levels of intelligence into welding machines. From our perspective, an intelligent machine should: incorporate knowledge of the welding process, know if the process is operating correctly, know if the weld it is making is good or bad, have the ability to learn from its experience to perform welds, and be able to optimize its own performance. To this end, we are researching machine architecture, methods of knowledge representation, decision making and conflict resolution algorithms, methods of learning and optimization, human/machine interfaces, and various sensors. This paper presents work on the machine architecture and the human/machine interface specifically for a robotic, gas metal arc welding cell. Although the machine control problem is normally approached from the perspective of having a central body of control in the machine, we present a design using distributed agents. A prime goal of this work is to develop an architecture for an intelligent machine that will support a modular, plug and play standard. A secondary goal of this work is to formulate a human/machine interface that treats the human as an …

Nonperturbative and perturbative interaction mechanisms of Wilson loops in gluodynamics are studied within the background field formalism. The first one operates when distance between minimal surfaces of the loops is small and may be important for sea quark effects and strong decay processes. The second mechanism -- perturbative interaction in nonperturbative confining background is found to be physically dominant for all loop configurations characteristic of scattering process. It reduces to perturbative gluon exchanges at small distances, while at larger distances it corresponds to the t-channel exchange of (reggeized) glueball states. Comparison to other approaches is made and possible physical applications are discussed.