Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone’s back yard); most of these storage sites include a surface barrier (cap) to prevent migration of the waste due to infiltration of surface water. The design lifespan for such barriers ranges from 30 to 1000 years, depending on hazard and regulations. In light of historical performance, society needs a better basis for predicting barrier performance over long time periods and tools for optimizing maintenance of barriers while in service. We believe that, as in other industries, better understanding of the dynamics of barrier system degradation will enable improved barriers (cheaper, longer-lived, simpler, easier to maintain) and improved maintenance. We are focusing our research on earthen caps, especially those with evapo-transpiration and capillary breaks. Typical cap assessments treat the barrier’s structure as static prior to some defined lifetime. Environmental boundary conditions such as precipitation and temperature are treated as time dependent. However, other key elements …

Hundreds of contaminated facilities and sites must be cleaned up. “Cleanup” includes decommissioning, environmental restoration, and waste management. Cleanup can be complex, expensive, risky, and time-consuming. Decisions are often controversial, can stall or be blocked, and are sometimes re-done - some before implementation, some decades later. Making and keeping decisions with long time horizons involves special difficulties and requires new approaches, including: • New ways (mental model) to analyze and visualize the problem, • Awareness of the option to shift strategy or reframe from a single decision to an adaptable network of decisions, and • Improved tactical processes that account for several challenges. These include the following: • Stakeholder values are a more fundamental basis for decision making and keeping than “meeting regulations.” • Late-entry players and future generations will question decisions. • People may resist making “irreversible” decisions. • People need “compelling reasons” to take action in the face of uncertainties. Our project goal is to make cleanup decisions easier to make, implement, keep, and sustain. By sustainability, we mean decisions that work better over the entire time-period—from when a decision is made, through implementation, to its end point. That is, alternatives that can be kept “as is” or …

We discuss the question of equilibration in heavy ion collisions and how it can be addressed in experiment.

Society has and will continue to generate hazardous wastes whose risks must be managed. For exceptionally toxic, long-lived, and feared waste, the solution is deep burial, e.g., deep geological disposal at Yucca Mtn. For some waste, recycle or destruction/treatment is possible. The alternative for other wastes is storage at or near the ground level (in someone’s back yard); most of these storage sites include a surface barrier (cap) to prevent downward water migration. Some of the hazards will persist indefinitely. As society and regulators have demanded additional proof that caps are robust against more threats and for longer time periods, the caps have become increasingly complex and expensive. As in other industries, increased complexity will eventually increase the difficulty in estimating performance, in monitoring system/component performance, and in repairing or upgrading barriers as risks are managed. An approach leading to simpler, less expensive, longer-lived, more manageable caps is needed. Our project, which started in April 2002, aims to catalyze a Barrier Improvement Cycle (iterative learning and application) and thus enable Remediation System Performance Management (doing the right maintenance neither too early nor too late). The knowledge gained and the capabilities built will help verify the adequacy of past remedial decisions, …

This report presents the work that followed the CSSX model development completed in FY2002. The developed cesium and potassium extraction model was based on extraction data obtained from simple aqueous media. It was tested to ensure the validity of the prediction for the cesium extraction from actual waste. Compositions of the actual tank waste were obtained from the Savannah River Site personnel and were used to prepare defined simulants and to predict cesium distribution ratios using the model. It was therefore possible to compare the cesium distribution ratios obtained from the actual waste, the simulant, and the predicted values. It was determined that the predicted values agree with the measured values for the simulants. Predicted values also agreed, with three exceptions, with measured values for the tank wastes. Discrepancies were attributed in part to the uncertainty in the cation/anion balance in the actual waste composition, but likely more so to the uncertainty in the potassium concentration in the waste, given the demonstrated large competing effect of this metal on cesium extraction. It was demonstrated that the upper limit for the potassium concentration in the feed ought to not exceed 0.05 M in order to maintain suitable cesium distribution ratios.

Visible light-photocatalysis could provide a cost-effective route to recycle CO{sub 2} to useful chemicals or fuels. Research is planned to study the reactivity of adsorbates, their role in the photosynthesis reaction, and their relation to the nature of surface sites during photosynthesis of methanol and hydrocarbons from CO{sub 2}/H{sub 2}O over four types of MCM-41/Al{sub 2}O{sub 3}-supported TiO{sub 2} and CdS catalysts: (1) ion-exchanged metal cations, (2) highly dispersed cations, (3) monolayer sites, and (4) modified monolayer catalysts. TiO{sub 2} was selected since it has exhibited higher activity than other oxide catalysts; CdS was selected for its photocatalytic activity in the visible light region. Al{sub 2}O{sub 3} provides excellent hydrothermal stability. MCM-41 offers high surface area (more than 800 m{sup 2}/g), providing a platform for preparing and depositing a large number of active sites per gram catalyst. The unique structure of these ion exchange cations, highly dispersed cations, and monolayer sites provides an opportunity to tailor their chemical/coordination environments for enhancing visible-light photocatalytic activity and deactivation resistance. The year one research tasks include (1) setting up experimental system, (2) preparing ion-exchanged metal cations, highly dispersed cations, monolayer sites of TiO{sub 2} and CdS, and (3) determination of the dependence of …

During robot path planning and control the equations that describe the robot motions are determined and solved. Historically these expressions were derived analytically off-line. For robots that must adapt to their environment or perform a wide range of tasks, a way is needed to rapidly re-derive these expressions to take into account the robot kinematic changes, such as when a tool is added to the end-effector. The JFKengine software was developed to automatically produce the expressions representing the manipulator arm motion, including the manipulator arm Jacobian and the forward kinematic expressions. Its programming interface can be used in conjunction with robot simulation software or with robot control software. Thus, it helps to automate the process of configuration changes for serial robot manipulators. If the manipulator undergoes a geometric change, such as tool acquisition, then JFKengine can be invoked again from the control or simulation software, passing it parameters for the new arm configuration. This report describes the automated processes that are implemented by JFKengine to derive the kinematic equations and the programming interface by which it is invoked. Then it discusses the tree data structure that was chosen to store the expressions, followed by several examples of portions of expressions …

We employ a novel, ultrafast terahertz probe to investigatethe dynamical interplay of optically-induced excitons and unboundelectron-hole pairs in GaAs quantum wells. Resonant creation ofheavy-hole excitons induces a new low-energy oscillator linked totransitions between the internal exciton degrees of freedom. The timeresolved terahertz optical conductivity is found to be a probe wellsuited for studies of fundamental processes such as formation, relaxationand ionization of excitons.

Roadmapping is a powerful tool to manage technical risks and opportunities associated with complex problems. Roadmapping identifies technical capabilities required for both project- and program-level efforts and provides the basis for plans that ensure the necessary enabling activities will be done when needed. Roadmapping reveals where to focus further development of the path forward by evaluating uncertainties for levels of complexity, impacts, and/or the potential for large payback. Roadmaps can be customized to the application, a “graded approach” if you will. Some roadmaps are less detailed. We have called these less detailed, top-level roadmaps “mini-roadmaps”. These miniroadmaps are created to tie the needed enablers (e.g., technologies, decisions, etc.) to the functions. If it is found during the mini-roadmapping that areas of significant risk exist, then those can be roadmapped further to a lower level of detail. Otherwise, the mini-roadmap may be sufficient to manage the project / program risk. Applying a graded approach to the roadmapping can help keep the costs down. Experience has indicated that it is best to do mini-roadmapping first and then evaluate the risky areas to determine whether to further evaluate those areas. Roadmapping can be especially useful for programs / projects that have participants from …

NERI Project No.2000-0109 began in August 2000 and has three tasks. The first project year addressed Task 1, namely development of nonlinear prognostication for critical equipment in nuclear power facilities. That work is described in the first year's annual report (ORNLTM-2001/195). The current (second) project year (FY02) addresses Task 2, while the third project year will address Tasks 2-3. This report describes the work for the second project year, spanning August 2001 through August 2002, including status of the tasks, issues and concerns, cost performance, and status summary of tasks. The objective of the second project year's work is a compelling demonstration of the nonlinear prognostication algorithm using much more data. The guidance from Dr. Madeline Feltus (DOE/NE-20) is that it would be preferable to show forewarning of failure for different kinds of nuclear-grade equipment, as opposed to many different failure modes from one piece of equipment. Long-term monitoring of operational utility equipment is possible in principle, but is not practically feasible for the following reason. Time and funding constraints for this project do not allow us to monitor the many machines (thousands) that will be necessary to obtain even a few failure sequences, due to low failure rates (<10{sup …

Railroads are important to the U.S. economy. They transport freight efficiently, requiring less energy and emitting fewer pollutants than other modes of surface transportation. While the railroad industry has steadily improved its fuel efficiency--by 16% over the last decade--more can, and needs to, be done. The ability of locomotive manufacturers to conduct research into fuel efficiency and emissions reduction is limited by the small number of locomotives manufactured annually. Each year for the last five years, the two North American locomotive manufacturers--General Electric Transportation Systems and the Electro-Motive Division of General Motors--have together sold about 800 locomotives in the United States. With such a small number of units over which research costs can be spread, outside help is needed to investigate all possible ways to reduce fuel usage and emissions. Because fuel costs represent a significant portion of the total operating costs of a railroad, fuel efficiency has always been an important factor in the design of locomotives and in the operations of a railroad. However, fuel efficiency has recently become even more critical with the introduction of strict emission standards by the U.S. Environmental Protection Agency, to be implemented in stages (Tiers 0, 1, and 2) between 2000 and …

A 3-dimensional coal structural model for the Argonne Premium Coal Pocahontas No. 3 has been generated. The model was constructed based on the wealth of structural information available in the literature with the enhancement that the structural diversity within the structure was represented implicitly (for the first time) based on image analysis of HRTEM in combination with LDMS data. The complex and large structural model (>10,000 carbon atoms) will serve as a basis for examining the interaction of gases within this low volatile bituminous coal. Simulations are of interest to permit reasonable simulations of the host-guest interactions with regard to carbon dioxide sequestration within coal and methane displacement from coal. The molecular structure will also prove useful in examining other coal related behavior such as solvent swelling, liquefaction and other properties. Molecular models of CO{sub 2} have been evaluated with water to analyze which classical molecular force-field parameters are the most reasonable to predict the interactions of CO{sub 2} with water. The comparison of the molecular force field models was for a single CO{sub 2}-H{sub 2}O complex and was compared against first principles quantum mechanical calculations. The interaction energies and the electrostatic interaction distances were used as criteria in the …

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The report presents the results of laboratory measurements performed on The Watt Stopper's LS-201 photosensor at the Lawrence Berkeley National Laboratory in January 2003. The purpose of these measurements was to characterize the spatial and spectral response function of the LS-201 photosensor. Sample results of the spectral response and spatial response are shown.

Previously reported stress corrosion cracking (SCC) rates for Alloy 82H gas-tungsten-arc welds tested in 360 C water showed tremendous variability. The excessive data scatter was attributed to the variations in microstructure, mechanical properties and residual stresses that are common in welds. In the current study, however, re-evaluation of the SCC data revealed that the large data scatter was an anomaly due to erroneous crack growth rates inferred from crack mouth opening displacement (CMOD) measurements. Apparently, CMOD measurements provided reasonably accurate SCC rates for some specimens, but grossly overestimated rates in others. The overprediction was associated with large unbroken ligaments that often form in welds in the wake of advancing crack fronts. When ligaments were particularly large, they prevented crack mouth deflection, so apparent crack incubation times (i.e. period of time before crack advance commences) based on CMOD measurements were unrealistically long. During the final states of testing, ligaments began to separate allowing the crack mouth to open rather quickly. This behavior was interpreted as a rapid crack advance, but it actually reflects the ligament separation rate, not the SCC rate. Revised crack growth rates obtained in this study exhibit substantially less scatter than that previously reported. The effects of crack …

A number of studies have shown substantial particulate matter (PM) reductions for biodiesel, but also a significant increase in nitrogen oxides (NOx) emissions. This study examines a number of approaches for NOx reduction from biodiesel.

The goal of this proposed effort was to assess the difficulty in identifying and characterizing virulence candidate genes in an organism for which very limited data exists. This was accomplished by first addressing the finishing phase of draft-sequenced F. tularensis genomes and conducting comparative analyses to determine the coding potential of each genome; to discover the differences in genome structure and content, and to identify potential genes whose products may be involved in the F. tularensis virulence process. The project was divided into three parts: (1) Genome finishing: This part involves determining the order and orientation of the consensus sequences of contigs obtained from Phrap assemblies of random draft genomic sequences. This tedious process consists of linking contig ends using information embedded in each sequence file that relates the sequence to the original cloned insert. Since inserts are sequenced from both ends, we can establish a link between these paired-ends in different contigs and thus order and orient contigs. Since these genomes carry numerous copies of insertion sequences, these repeated elements ''confuse'' the Phrap assembly program. It is thus necessary to break these contigs apart at the repeated sequences and individually join the proper flanking regions using paired-end information, or …

Final report for a research program in theoretical nuclear physics to develop methods and computer programs to perform ab initio calculations for light nuclei ranging from Helium to Oxygen. The method employed is based effective interaction theory within the framework of the shell model. The principal accomplishments were: (1) participation in the validation of ab initio for {sup 4}He; the first study of A = 6 nuclei with the realistic, non-local CD-Bonn potential; (2) a study of ''intruder'' states in {sup 8}Be, (3) the first shell-model calculations implementing three-body clusters in the effective interaction for nuclei with A > 4; (4) the discovery that two-nucleon interactions by themselves are inadequate to describe the structure of the nucleus {sup 10}B, which provides proof that three-nucleon forces affect nuclear structure; (5) first calculations including the Tucson-Melbourne three-nucleon force, which gives better agreement with the experimental spectrum for {sup 10}B and (6) the development of a new shell-model code designed for public release.

Despite the fact that chemical weathering of silicate rocks plays an important role in the draw-down of CO{sub 2} over geologic time scales (Berner and Berner, 1996), the overall controls on the rate of chemical weathering are still not completely understood. Lacking a mechanistic understanding of these controls, it remains difficult to evaluate a hypothesis such as that presented by Raymo and Ruddiman (1992), who suggested that enhanced weathering and CO{sub 2} draw-down resulting from the uplift of the Himalayas contributed to global cooling during the Cenozoic. At an even more fundamental level, the three to four order of magnitude discrepancy between laboratory and field weathering rates is still unresolved (White et al., 1996). There is as yet no comprehensive, mechanistic model for silicate chemical weathering that considers the coupled effects of precipitation, vadose zone flow, and chemical reactions. The absence of robust process models for silicate weathering and the failure to resolve some of these important questions may in fact be related-the controls on the overall rates of weathering cannot be understood without considering the weathering environment as one in which multiple, time-dependent chemical and physical processes are coupled (Malmstrom, 2000). Once chemical weathering is understood at a mechanistic …

The performance of object-oriented applications often suffers from the inefficient use of high-level abstractions provided by underlying libraries. Since these library abstractions are user-defined and not part of the programming language itself only limited information on their high-level semantics can be leveraged through program analysis by the compiler and thus most often no appropriate high-level optimizations are performed. In this paper we outline an approach based on source-to-source transformation to allow users to define optimizations which are not performed by the compiler they use. These techniques are intended to be as easy and intuitive as possible for potential users; i.e. for designers of object-oriented libraries, people most often only with basic compiler expertise.

We used synthetic aperture radar interferograms to image ground subsidence that occurred over the Dixie Valley geothermal field during different time intervals between 1992 and 1997. Linear elastic inversion of the subsidence that occurred between April, 1996 and March, 1997 revealed that the dominant sources of deformation during this time period were large changes in fluid volumes at shallow depths within the valley fill above the reservoir. The distributions of subsidence and subsurface volume change support a model in which reduction in pressure and volume of hot water discharging into the valley fill from localized upflow along the Stillwater range frontal fault is caused by drawdown within the upflow zone resulting from geothermal production. Our results also suggest that an additional source of fluid volume reduction in the shallow valley fill might be similar drawdown within piedmont fault zones. Shallow groundwater flow in the vicinity of the field appears to be controlled on the NW by a mapped fault and to the SW by a lineament of as yet unknown origin.

This report is a summary of the discussion sessions of the 12th Workshop on Crystalline Silicon Solar Cells and Processes. The theme of the workshop was"Fundamental R&D in c-Si: Enabling Progress in Solar-Electric Technology." This theme was chosen to reflect a concern that the current expansion in the PV energy production may redirect basic research efforts to production-oriented issues. The PV industry is installing added production capacity and new production lines that include the latest technologies. Once the technologies are selected, it is difficult to make changes. Consequently, a large expansion can stagnate the technologies and diminish interest in fundamental research. To prevent the fundamental R&D program from being overwhelmed by the desire to address immediate engineering issues, there is a need to establish topics of fundamental nature that can be pursued by the universities and the research institutions. Hence, one of the objectives of the workshop was to identify such areas for fundamental research.

The power of a quantum computer (QC) relies on the fundamental concept of the superposition in quantum mechanics and thus allowing an inherent large-scale parallelization of computation. In a QC, binary information embodied in a quantum system, such as spin degrees of freedom of a spin-1/2 particle forms the qubits (quantum mechanical bits), over which appropriate logical gates perform the computation. In classical computers, the basic unit of information is the bit, which can take a value of either 0 or 1. Bits are connected together by logic gates to form logic circuits to implement complex logical operations. The expansion of modern computers has been driven by the developments of faster, smaller and cheaper logic gates. As the size of the logic gates become smaller toward the level of atomic dimensions, the performance of such a system is no longer considered classical but is rather governed by quantum mechanics. Quantum computers offer the potentially superior prospect of solving computational problems that are intractable to classical computers such as efficient database searches and cryptography. A variety of algorithms have been developed recently, most notably Shor's algorithm for factorizing long numbers into prime factors in polynomial time and Grover's quantum search algorithm. …

The identification of individual molecules and the determination of how these interact with their local environment are critical steps toward a better understanding of complex organic systems. Optical detection techniques have always played a key role in the nondestructive and noninvasive analysis of complex materials. Until recently, however, optical microscopy has lacked the sensitivity to study processes on the molecular scale. This has changed with the recent development of new schemes that limit the optical detection volume, and the advent of new, highly quantum-efficient photon detectors. These inventions have enabled researchers to optically probe biomolecular processes at the single molecule level by observing the fluorescence of specific marker molecules. The requirement to specifically label biomolecules and the fact, that fluorescence emission is prone to photodecomposition of the marker molecules, however, have limited this approach to a few, well-characterized case studies. Raman scattering, is one of few optical techniques that can identify atomic species and in addition determine their chemical bonds by observing their distinct vibrational fingerprints; but it is orders of magnitude weaker than fluorescence. In this project, we have developed new optical probes that allow for the non-destructive characterization and identification of organic and inorganic matter at the single …