We describe a general strategy we have found effective for parallelizing solid mechanics simula- tions. Such simulations often have several computationally intensive parts, including finite element integration, detection of material contacts, and particle interaction if smoothed particle hydrody- namics is used to model highly deforming materials. The need to balance all of these computations simultaneously is a difficult challenge that has kept many commercial and government codes from being used effectively on parallel supercomputers with hundreds or thousands of processors. Our strategy is to load-balance each of the significant computations independently with whatever bal- ancing technique is most appropriate. The chief benefit is that each computation can be scalably paraIlelized. The drawback is the data exchange between processors and extra coding that must be written to maintain multiple decompositions in a single code. We discuss these trade-offs and give performance results showing this strategy has led to a parallel implementation of a widely-used solid mechanics code that can now be run efficiently on thousands of processors of the Pentium-based Sandia/Intel TFLOPS machine. We illustrate with several examples the kinds of high-resolution, million-element models that can now be simulated routinely. We also look to the future and dis- cuss what possibilities …

The generation of surface defects on electron cyclotron resonance (ECR) plasma derived aluminum oxide films has been studied. We find that Cl active O vacancies can be generated using electron and ion irradiation yielding surface concentrations of 3 xl 013 to 1X1014 sites"cm-2. These values correspond to surface defect concentrations of 3 to 10% when compared to ordered, crystalline u-alumina. The vacancies appear to be responsible for increased surface O concentrations when immersed in water. Anodic polarization of irradiated films yields a decrease in the stable pitting potential which correlates with electron dose.

The APT blanket system has about 57 MW of thermal energy deposited within the blanket region under normal operating conditions from the release of neutrons and the interaction of the High energy particles with the blanket materials. This corresponds to about 48 percent of total thermal energy deposited in the APT target/blanket system. The deposited thermal energy under normal operation conditions is an important input parameter used in the thermal-hydraulic design and accident analysis.

The data obtained from the tests described in this document provide results for determining tank size for in the proposed Small-Tank Tetraphenylborate (STTP) facility.

The National Ignition Facility, currently under design and construction at Lawrence Livermore National Laboratory, will be the world`s largest laser when complete. The NIF will use about 8,000 large optics of 26 different types to focus up to 192 laser beams on a dime-size target. Given the constraints of the NIF operating environment, the tasks associated with optics transport and handling require a novel, versatile transport system. The system will consist of a computer system containing guidance, traffic management and order entry functions, and four or more automated laser-guided vehicles. This transport system will transport optics enclosures that are essentially portable clean rooms and will lift, align, and position them as needed to contact and engage mating points on the laser support structure.

This report is one of a series of reports documenting accident scenario simulations for the Accelerator Production of Tritium (APT) blanket heat removal systems. The simulations were performed in support of the Preliminary Safety Analysis Report (PSAR) for the APT.

The direct grout alternative is a viable option for treatment/stabilization and disposal of salt waste containing Cs-137 concentrations of 1-3 Ci/gal. The composition of the direct grout salt solution is higher in sodium salts and contains up to a few hundred ppm Cs-137 more than the current reference salt solution. However it is still similar to the composition of the current reference salt solution. Consequently, the processing, setting, and leaching properties (including TCLP for Cr and Hg) of the direct grout and current saltstone waste forms are very similar. The significant difference between these waste solutions is that the high cesium salt solution will contain between 1 and 3 Curies of Cs-137 per gallon compared to a negligible amount in the current salt solution. This difference will require special engineering and shielding for a direct grout processing facility and disposal units to achieve acceptable radiation exposure conditions. The Cs-137 concentration in the direct grout salt solution will also affect the long-term curing temperature of the waste form since 4.84 Watts of energy are generated per 1000 Ci of Cs-137. The temperature rise of the direct grout during long-term curing has been calculated by A. Shaddy, SRTC.1 The effect of curing …

This supporting document has been prepared to make the FDNW calculations for Project W-320, readily retrievable. These calculations are required: To determine the power requirements needed to power electrical heat tracing segments contained within three manufactured insulated tubing assemblies; To verify thermal adequacy of tubing assembly selection by others; To size the heat tracing feeder and branch circuit conductors and conduits; To size protective circuit breaker and fuses; and To accomplish thermal design for two electrical heat tracing segments: One at C-106 tank riser 7 (CCTV) and one at the exhaust hatchway (condensate drain). Contents include: C-Farm electrical heat tracing; Cable ampacity, lighting, conduit fill and voltage drop; and Control circuit sizing and voltage drop analysis for the seismic shutdown system.

A transient natural convection model of the APT blanket primary heat removal (HR) system was developed to demonstrate that the blanket could be cooled for a sufficient period of time for long term cooling to be established following a loss-of-flow accident (LOFA). The particular case of interest in this report is a complete loss-of-pumping accident. For the accident scenario in which pumps are lost in both the target and blanket HR systems, natural convection provides effective cooling of the blanket for approximately 68 hours, and, if only the blanket HR systems are involved, natural convection is effective for approximately 210 hours. The heat sink for both of these accident scenarios is the assumed stagnant fluid and metal on the secondary sides of the heat exchangers.

This document is the analytical laboratory report for tank 241-TX-104 push mode core segments collected between February 18, 1998 and February 23, 1998. The segments were subsampled and analyzed in accordance with the Tank 241-TX-104 Push Mode Core Sampling and Analysis Plan (TSAP) (McCain, 1997), the Data Quality Objective to Support Resolution of the Organic Complexant Safety Issue (Organic DQO) (Turner, et al., 1995) and the Safety Screening Data Quality Objective (DQO) (Dukelow, et.al., 1995). The analytical results are included in the data summary table. None of the samples submitted for Differential Scanning Calorimetry (DSC) and Total Alpha Activity (AT) exceeded notification limits as stated in the TSAP. The statistical results of the 95% confidence interval on the mean calculations are provided by the Tank Waste Remediation Systems Technical Basis Group in accordance with the Memorandum of Understanding (Schreiber, 1997) and are not considered in this report. Appearance and Sample Handling Attachment 1 is a cross reference to relate the tank farm identification numbers to the 222-S Laboratory LabCore/LIMS sample numbers. The subsamples generated in the laboratory for analyses are identified in these diagrams with their sources shown. Core 230: Three push mode core segments were removed from tank 241-TX-104 …

This report provides background information for a series of reports documenting accident scenario simulations for the Accelerator Production of Tritium (APT) blanket heat removal systems. The simulations were performed in support of the Preliminary Safety Analysis Report for the APT. This report gives a brief description of the FLOWTRAN-TF code which was used for detailed blanket bin modeling.

Cross-flow filtration is being evaluated as a pretreatment in the proposed treatment processes for aqueous high-level radioactive wastes at Oak Ridge National Laboratory (ORNL) to separate insoluble solids from aqueous waste from the Melton Valley Storage Tanks (MVST).

The Ceramicrete{trademark} waste form is a magnesium phosphate hydrate, which sets as the result of an acid-base reaction between KH{sub 2}PO{sub 4} and MgO in the presence of water. Based on the results of this feasibility study, this low temperature ceramic waste form is acceptable for stabilization of cesium loaded crystalline silicotitanate (CST) resin. The performance objective of CST stabilization is to convert a friable powdered resin into a monolithic form to improve handling and storage and to reduce the waste mobility. Advantages of this type of the CST-Ceramicrete{trademark} waste form include: room temperature processing of a fluid slurry, limited off gas, flexible mix designs, rapid setting, no free liquids, temperature tolerant and durable up to at least 90 degrees C. The Ceramicrete/220 waste form can be processed by in-container mixing or by batch mixing. Since a trace amount of free water will be associated with the wet resin in the CST-Ceramicrete{trademark} waste form, radiolysis of the free water may cause pressurization of the containers. Leaching tests were conducted to evaluate the CST-Ceramicrete{trademark} waste form performance relative to high-level waste glass. Results were very encouraging given that only one waste loading (50 wt. percent resin) was tested and that the …

The NuDat program provides a user with access to nuclear properties and to some nuclear reaction data. The program operates on DEC VMS operating systems and on PC`s with Microsoft operating systems. The program has four user interfaces, all having the same content and functionality. These interfaces are Web, Video and Sequential for VMS. The PC interface is identical to the VMS Video interface. Forms are used to supply the type of data the user desires, the retrieval parameters, the output format, and the sort order of the data. The program and associated database is used in basic research, particularly for the systematic study of nuclear properties. It is also a useful tool for applied research to identify radiations from radionuclides contained in environmental samples, or from those produced by neutron or charged particle activation. The NuDat database is derived from several databases maintained by the National Nuclear Data Center. The databases are the Adopted Levels and Gammas data sets from ENSDF, the Nuclear Wallet Cards, Decay Radiations derived from ENSDF decay data sets processed by RADLIST, and Thermal Neutron Cross Sections.

produced in 1996 and shipped to pharmaceutical houses for evaluation of compatibility with oxime solution used to precipitate `?vfo as the oxime complex is both air and light-sensitive, and containing a black precipitate that forms during shipment, presumably as a result of self- irradiation. Addition of sodium hypochlorite to the product solution prior to shipment prevents precipitate formation, indicating the precipitate is a reduced form of `%lo. to remove any precipitate. Duplicate aliquots of the filtered samples were titrated to a phenolphthalein irradiation and afler standing at room temperature for 86.4 hours. Precipitates were washed to a FTIR analysis of the white precipitate showed it to be alpha benzoin oxime. Since the basic After 86.4 hours, no precipitate had formed in bottles containing sodium hypochlorite. Black precipitate had formed in all bottles that did not contain sodium hypochlorite after 14.4 hours. The precipitate appeared to initially form on the surface of the HDPE sample bottles and Black precipitate was first noticed in sample set 1 after 28.8 hrs' irradiation. No visible sample containing precipitate was kept at room temperature in the original bottle. Precipitate in sample sets 2 and 3. Since no precipitate formed in these bottles, this was equivalent …

The report summarizes the accomplishments, publications, and reception of this program in the catalyst and microanalytical communities. Initially the research covered a wide range of catalysts, but later in the program, the author prepared and optimized a highly active catalyst for low-temperature NO abatement in fossil fuel power plants. During the course of the program, several innovations in microanalytical instrumentation and technique were developed specifically for analysis of catalytic nanoparticles. New designs for improved nanoparticle elemental sensitivity were proposed and accepted by the manufacture of Lehigh`s new VG /HB-603 analytical electron microscope. New tests for assessing elemental sensitivity have been devised and used to encourage the manufacturer to build the most sensitive analytical electron microscope in the world. Accomplishments summarized for the 1986--1990 period include: Quantitative measurements of noble metal distributions in alumina monoliths; Direct elemental imaging of small metal particles poisoned by sulfur: Analysis of surface species on Co/La/alumina catalyst; and Development of analytical electron microscopy methods. Accomplishments for the 1991--1993 period include: Catalytic testing facility for the electron microscopy lab; New scheme for immobilization of surface species for AEM analysis; and New method for electron probe microanalysis of porous materials. Accomplishments for the 1994--1998 period were: successful low-temperature …

The authors describe a theoretical model to study the transmission of relativistic H{sup {minus}} ions through thin carbon foils. The approach is based on a Monte Carlo solution of the Langevin equation describing electronic excitations of the atoms during the transport through the foil. Calculations for the subshell populations of outgoing hydrogen atoms are found to be in good agreement with recent experimental data on an absolute scale and show that there exists a propensity for populating extreme Stark states.

This grant provided access to the massively parallel computing facilities at Oak Ridge National Laboratory for the study of lattice gauge theory. The major project was a calculation of the weak decay constants of pseudoscalar mesons with one light and one heavy quark. A number of these constants have not yet been measured, so the calculations constituted a set of predictions which will be tested by future experiments. More importantly, f{sub B} and f{sub B{sub s}}, the decay constants of the B and B{sub s} mesons, are crucial inputs for extracting information regarding the CKM matrix element V{sub td} from experimental measurements of B-{anti B} mixing, and future measurements of B{sub s}-{anti B}{sub s} mixing planned for the B-factory currently under construction at the Stanford Linear Accelerator Center. V{sub td} is one of the least well determined parameters of the Standard Model of High Energy Physics. It does not appear likely that F{sub B} and f{sub B{sub s}} will be measured experimentally in the near future, so lattice calculations such as this will play a crucial role in extracting information about the Standard Model from the B-factory experiments. The author has carried out the most accurate calculations of the heavy-light …

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We present the results on the a.c. transport of electrons moving through a two-dimensional (2D) semiconductor quantum point contact (QPC). We concentrate our attention on the characteristic properties of the high frequency admittance ({omega}{approximately}0 - 50 GHz), and on the oscillations of the admittance in the vicinity of the separatrix (when a channel opens or closes), in presence of the relaxation effects. The experimental verification of such oscillations in the admittance would be a strong confirmation of the semi-classical approach to the a.c. transport in a QPC, in the separatrix region.

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We numerically simulate the process of nuclear spin measurement in Kane's quantum computer. For this purpose, we model the quantum dynamics of two coupled nuclear spins located on {sup 31}P donors implanted in Si. We estimate the minimum time of measurement necessary for the reliable transfer of quantum information from the nuclear spin subsystem to the electronic one and the probability of error for typical values of external noise.

A method of immobilizing mixed low-level waste is provided which uses low cost materials and has a relatively long hardening period. The method includes: forming a mixture of iron oxide powders having ratios, in mass %, of FeO: Fe{sub 2}O{sub 3}: Fe{sub 3}O{sub 4} equal to 25-40: 40-10: 35-50, or weighing a definite amount of magnitite powder. Metallurgical cinder can also be used as the source of iron oxides. A solution of the orthophosphoric acid, or a solution of the orthophosphoric acid and ferric oxide, is formed and a powder phase of low-level waste and the mixture of iron oxide powders or cinder (or magnetite powder) is also formed. The acid solution is mixed with the powder phase to form a slurry with the ratio of components (mass %) of waste: iron oxide powders or magnitite: acid solution = 30-60: 15-10: 55-30. The slurry is blended to form a homogeneous mixture which is cured at room temperature to form the final product.