BS>The use of a lead-bismuth alloy as a coolant in the removal of heat from power-generating nuclear reactors was considered with the possibility that its ternary alloy with uranium or plutonium might be of use in a reactor of the circulating-liquid-fuel type. Information collected from the literature covering phase-equilibrium studies, physicalproperty data, and reactivity of this alloy toward other substances is presented. (auth)

Laser amplifier frames fabricated from Type 304 stainless steel are known to cause damage to glass lenses by ejecting particles which are deposited on the lenses. High energy pulses of xenon light interact with the steel surface to produce damage sites. Heat treatment and surface cleaning procedures greatly affect the surface stability of the steel and influence contamination generated by the steel. It is believed that inclusions and/or carbides play a role, and the size of damage sites observed on glass correlate with the size of nonmetallic phases in the steel. Thermal etching of the steel was found to be a principle mechanism of surface damage caused by the high energy xenon light.

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The stress analysis is presented for the proposed loop seal modification to the LOFT Steam Generator Main Feed Piping. THE SAP IV finite element computer program was used to analyze normal, upset, emergency, and faulted conditions. Results of the analysis indicate that the modified main feed piping system will satisfy all structural adequacy criteria specified in Subarticle NC-3650 of the ASME Boiler and Pressure Vessel Code. Results also show that the isolation snubber configuration, specified in LTR 115-11, will also be adequate for the piping configuration analyzed.

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Aqueous methods for recovering uranium from BeO- and Al/sub 2/O/sub 3/- base gas-cooled-reactor fuel elements are being evaluated. Two methods for processing Hastelloy-X--clad pelletized BeO-base fuels containing 60 to 70% UO/ sub 2/, such as the GCRE and MGCR, seem feasible. One method involves mechanical stripping or chopping of the cladding followed by leaching of the uranium from the fuel pellets with boiling 6-l3M HNO/sub 3/. In the other method the cladding and UO/sub 2/ are dissolved in boiling 2M HNO/sub 3/-4M HCl. In either case, most of the BeO matrix remains as an undissolved residue. Pellets containing 70% UO/sub 3/ dissolved completely in less than 20 hr in boiling 8M HNO/sub 3/ containing either 2M H/sub 2/SO/sub 4/ or 0.5M HF, producing solutions containing 4 g of uranium per liter. Fuels of high BeO content, e.g. BeO--5% UO/sub 2/, dissolved only slowly in boiling aqueous reagents. Highest initial rates were in sulfuric acid solutions, log (Rate, mg min/sup -1/cm/sup -2/) = 0.223 (H/sub 2/SO/ sub 4, M) - 2.8l and in HF--NH/sub 4/F solutions. ln boiling 5-8M NH/sub 4/F the initial dissolution rate increased from 0.07 to 3.5 mg min/sup -1/cm/sup -2/ as the HF concentration increased from 0 …

Preparation of CdS films by evaporation from a single graphite source, as generally used by the Institute of Energy Conversion (IEC) group at the University of Delaware, has been implemented. Previously at Westinghouse, four evaporation sources were used to permit uniform coverage of large area substrates. The graphite source used in this period is somewhat smaller than the IEC design to permit accommodation to the heater geometry currently available. Initial efforts with the single source evaporation have been on characterizing the thickness profiles of the deposited films. This is needed to permit selection of conditions for obtaining films of about 30..mu..m thickness over the central 4 cm x 4 cm area of the substrate. Barrier processing according to the details of IEC method has been used on four-source CdS films. To date the best cells have only been about 1% efficient. Low short circuit current density values (approx. 5 mA/cm/sub 2/) have been the biggest problem. Annealing in 6% H/sub 2//Ar mixtures at 170/sup 0/C after electrode grid evaporation generally has resulted in reduced values of J/sub sc/. Plans for the next period include the use of single source films for cell processing and the use of small area diode …

Reduced instrument responses are presented for Thermal-Hydraulic Test Facility (THTF) test 104, which is part of the ORNL Pressurized-Water Reactor (PWR) Blowdown Heat Transfer Separate-Effects Program. The objective of the program is to investigate the thermal-hydraulic phenomenon governing the energy transfer and transport processes that occur during a loss-of-coolant accident in the PWR system. Test 104 was conducted to obtain CHF in bundle 1 under blowdown conditions. The primary purpose of this report is to make the reduced instrument responses during test 104 available.

Progress on a program to develop commercially viable phosphoric acid fuel cell driven on-site integration energy systems is presented. A mass and energy balance was completed for one operating point of a selected power generation sub-system with a power output of 119 kW. Potentially, 87% of the LHV of the input fuel is available as bus bar electricity or useful heat. A 2 kW stack of conventional design and a 0.5 kW DIGAS cooled stack have been constructed and are on test at ERC. Renovation of a space for the Westinghouse stack test facility is underway and procurement of equipment has been initiated. The coupled cell temperature - current density analysis has been modified to include the effects of turbulent coolant flow and extended to permit analysis of up to 10 process plates between cooling plates. The REFORM computer program was verified by comparison with data received from the government project manager. A method for predicting carbon deposition was developed and compared with data from the literature.

Initial studies of p-n heterojunctions formed between undoped trans-(CH)/sub x/ and n-CdS are reported. The junctions were characterized by measurements of current vs voltage (I-V), capacitance vs voltage (C-V), and photovoltaic response spectra. The results are analyzed in terms of the standard heterojunction equations. It is concluded that undoped as-grown films of trans-(CH)/sub x/ are p-type with a residual acceptor concentration of 2 x 10/sup 18/ cm/sup -3/, and that in spite of the complex fibril morphology the semiconductor properties can be inferred by treating (CH)/sub x/ as an effective homogeneous medium. Detailed studies of the photovoltaic response at energies below the energy gap for (CH)/sub x/ imply the existence of a well-defined deep trapping state in polyacetylene with an energy near the center of the gap.

In accordance with ASME Code, Section III requirements, all analyses of Class I components must be independently reviewed. Since the LOFT blowdown loop piping up through the blowdown valve is a Class I piping system, the thermal analyses are reviewed. The Thermal Analysis Branch comments to this review are also included. It is the opinion of the Thermal Analysis Branch that these comments satisfy all of the reviewers questions and that the analyses should stand as is, without additional considerations in meeting the ASME Code requirements and ANC Specification 60139.

MACRO, a code to propagate probability distributions through a set of linked models, is currently under development at Lawrence Livermore Laboratory. An early version of this code, MACRO1, has been used to assess post-sealing dose to man for simple repository and site models based on actual site data.

The interaction of the electron beam in the Advanced Test Accelerator with an azimuthally symmetric mode of the accelerating cells is investigated theoretically. The interaction possibly could cause modulation of the beam current at the resonant frequency of the mode. Values of the shunt impedance and Q value of the mode were obtained from previous measurement and analysis. Lagranian hydrodynamics is employed and a WKB solution to the equation of motion is obtained. Results indicate that the interaction will not be a problem in the accelerator.

This research project involves the design, synthesis and study of the molecules which mimic many of the important aspects of photosynthetic electron and energy transfer. Specifically, the molecules are designed to mimic the following aspects of natural photosynthetic multistep electron transfer: electron donation from a tetrapyrrole excited singlet state, electron transfer between tetrapyrroles, electron transfer from tetrapyrroles to quinones, and electron transfer between quinones with different redox properties. In addition, they model carotenoid antenna function in photosynthesis (singlet-singlet energy transfer from carotenoid polyenes to chlorophyll) and carotenoid photoprotection from singlet oxygen damage (triplet-triplet energy transfer from chlorophyll to carotenoids).

Nuclear wastes which are logical candidates for deep geologic disposal include commercial (spent fuel, reprocessing) and defense wastes. It is expected that the 5250 metric tons of spent fuel discharged through the end of 1978 would increase to about 100,000 tons by the end of 2000. The individual characteristics of each waste type (spent fuel, solidified waste, defense wastes) are described in turn. (DLC)

In June 2004, the Demonstration Bulk Vitrification System (DBVS) was initiated with the intent to design, construct, and operate a full-scale bulk vitrification pilot-plant to treat low-activity tank waste from Hanford Tank 241-S-109. The DBVS facility uses In-Container Vitrification{trademark} (ICV{trademark}) at the core of the treatment process. The basic process steps combine liquid low-activity waste (LAW) and glassformers; dry the mixture; and then vitrify the mixture in a batch feed-while-melt process in a refractory lined steel container. Off-gases are processed through a state-of-the-art air pollution control system including sintered-metal filtration, thermal oxidation, acid gas scrubbing, and high-efficiency particulate air (HEPA) and high-efficiency gas adsorber (HEGA) filtration. Testing has focused on development and validation of the waste dryer, ICV, and sintered-metal filters (SMFs) equipment, operations enhancements, and glass formulation. With a parallel testing and design process, testing has allowed improvements to the DBVS equipment configuration and operating methodology, since its original inception. Design improvements include optimization of refractory panels in the ICV, simplifying glassformer addition equipment, increasing the number of waste feed chutes to the ICV, and adding capability for remote clean-out of piping, In addition, the U.S. Department of Energy (DOE) has provided an independent review of the entire DBVS …

The purpose of this report is to summarize and evaluate the Argonne Distance Tabletop Exercise (DISTEX) method. DISTEX is intended to facilitate multi-organization, multi-objective tabletop emergency response exercises that permit players to participate from their own facility's incident command center. This report is based on experience during its first use during the FluNami 2007 exercise, which took place from September 19-October 17, 2007. FluNami 2007 exercised the response of local public health officials and hospitals to a hypothetical pandemic flu outbreak. The underlying purpose of the DISTEX method is to make tabletop exercising more effective and more convenient for playing organizations. It combines elements of traditional tabletop exercising, such as scenario discussions and scenario injects, with distance learning technologies. This distance-learning approach also allows playing organizations to include a broader range of staff in the exercise. An average of 81.25 persons participated in each weekly webcast session from all playing organizations combined. The DISTEX method required development of several components. The exercise objectives were based on the U.S. Department of Homeland Security's Target Capabilities List. The ten playing organizations included four public health departments and six hospitals in the Chicago area. An extent-of-play agreement identified the objectives applicable to each …

Decomposition of the time-reversal operator for an array, or equivalently the singular value decomposition of the multistatic response matrix, has been used to improve imaging and localization of targets in complicated media. Typically, each singular value is associated with one scatterer even though it has been shown in several cases that a single scatterer can generate several singular values. In this paper we review the analysis of the time-reversal operator (TRO), or equivalently the multistatic response matrix (MRM), of an array system and a small target. We begin with two-dimensional scattering from a small cylinder then show the results for a small non-spherical target in three dimensions. We show that the number and magnitudes of the singular values contain information about target composition, shape, and orientation.

Oak Ridge National Laboratory was tasked by the U.S. Army Engineering and Support Center (Huntsville, AL) to evaluate the mathematical basis of existing software tools used to assist the Army with the characterization of sites potentially contaminated with unexploded ordnance (UXO). These software tools are collectively known as SiteStats/GridStats. The first purpose of the software is to guide sampling of underground anomalies to estimate a site's UXO density. The second purpose is to delineate areas of homogeneous UXO density that can be used in the formulation of response actions. It was found that SiteStats/GridStats does adequately guide the sampling so that the UXO density estimator for a sector is unbiased. However, the software's techniques for delineation of homogeneous areas perform less well than visual inspection, which is frequently used to override the software in the overall sectorization methodology. The main problems with the software lie in the criteria used to detect nonhomogeneity and those used to recommend the number of homogeneous subareas. SiteStats/GridStats is not a decision-making tool in the classical sense. Although it does provide information to decision makers, it does not require a decision based on that information. SiteStats/GridStats provides information that is supplemented by visual inspections, land-use …

Surface display is a powerful technique that utilizes natural microbial functional components to express proteins or peptides on the cell exterior. Since the reporting of the first surface-display system in the mid-1980s, a variety of new systems have been reported for yeast, Gram-positive and Gram-negative bacteria. Non-conventional display methods are emerging, eliminating the generation of genetically modified microorganisms. Cells with surface display are used as biocatalysts, biosorbents and biostimulants. Microbial cell-surface display has proven to be extremely important for numerous applications ranging from combinatorial library screening and protein engineering to bioremediation and biofuels production.

This Nuclear Regulatory Commission (NRC) sponsored study has identified human-performance issues in new and advanced nuclear power plants. To identify the issues, current industry developments and trends were evaluated in the areas of reactor technology, instrumentation and control technology, human-system integration technology, and human factors engineering (HFE) methods and tools. The issues were organized into seven high-level HFE topic areas: Role of Personnel and Automation, Staffing and Training, Normal Operations Management, Disturbance and Emergency Management, Maintenance and Change Management, Plant Design and Construction, and HFE Methods and Tools. The issues where then prioritized into four categories using a 'Phenomena Identification and Ranking Table' methodology based on evaluations provided by 14 independent subject matter experts. The subject matter experts were knowledgeable in a variety of disciplines. Vendors, utilities, research organizations and regulators all participated. Twenty issues were categorized into the top priority category. This Brookhaven National Laboratory (BNL) technical report provides the detailed methodology, issue analysis, and results. A summary of the results of this study can be found in NUREG/CR-6947. The research performed for this project has identified a large number of human-performance issues for new control stations and new nuclear power plant designs. The information gathered in this project …

The temperature equilibration rate in dense hydrogen (for both T{sub i} > T{sub e} and T{sub i} < T{sub e}) has been calculated with large-scale molecular dynamics simulations for temperatures between 10 and 300 eV and densities between 10{sup 20}/cc to 10{sup 24}/cc. Careful attention has been devoted to convergence of the simulations, including the role of semiclassical potentials. We find that for Coulomb logarithms L {approx}> 1, Brown-Preston-Singleton [Brown et al., Phys. Rep. 410, 237 (2005)] with the sub-leading corrections and the fit of Gericke-Murillo-Schlanges [Gericke et al., PRE 65, 036418 (2003)] to the T-matrix evaluation of the collision operator, agrees with the MD data to within the error bars of the simulation. For more strongly-coupled plasmas where L {approx}< 1, our numerical results are consistent with the fit of Gericke-Murillo-Schlanges.

In 2006, a drilling campaign was conducted at the Project Shoal Area (PSA) to provide information for model validation, emplace long-term monitoring wells, and develop baseline geochemistry for long term hydrologic monitoring. Water levels were monitored in the vicinity of the drilling, in the existing wells HC-1 and HC-6, as well as in the newly drilled wells, MV-1, MV-2 and MV-3 and their associated piezometers. Periodic water level measurements were also made in existing wells HC-2, HC-3, HC-4, HC-5 and HC-7. A lithium bromide chemical tracer was added to drilling fluids during the installation of the monitoring and validation (MV) wells and piezometers. The zones of interest were the fractured, jointed and faulted horizons within a granitic body. These horizons generally have moderate hydraulic conductivities. As a result, the wells and their shallower piezometers required strenuous purging and development to remove introduced drilling fluids as evidenced by bromide concentrations. After airlift and surging well development procedures, the wells were pumped continuously until the bromide concentration was less then 1 milligram per liter (mg/L). Water quality samples were collected after the well development was completed. Tritium scans were preformed before other analyses to ensure the absence of high levels of radioactivity. …

We describe an efficient implementation and present aperformance study of an algebraic multilevel sub-structuring (AMLS)method for sparse eigenvalue problems. We assess the time and memoryrequirements associated with the key steps of the algorithm, and compareitwith the shift-and-invert Lanczos algorithm in computational cost. Oureigenvalue problems come from two very different application areas: theaccelerator cavity design and the normal mode vibrational analysis of thepolyethylene particles. We show that the AMLS method, when implementedcarefully, is very competitive with the traditional method in broadapplication areas, especially when large numbers of eigenvalues aresought.