This paper surveys theory issues associated with inducing convective cells through divertor tile biasing in a tokamak to broaden the scrape-off layer (SOL). The theory is applied to the Mega-Ampere Spherical Tokamak (MAST), where such experiments are planned in the near future. Criteria are presented for achieving strong broadening and for exciting shear-flow turbulence in the SOL; these criteria are shown to be attainable in practice. It is also shown that the magnetic shear present in the vicinity of the X-point is likely to confine the potential perturbations to the divertor region below the X-point, leaving the part of the SOL that is in direct contact with the core plasma intact. The current created by the biasing and the associated heating power are found to be modest.

The National Ignition Facility (NIF) is now under construction at the Lawrence Livermore National Laboratory (LLNL). The Power Conditioning System (PCS) for NIF, when completed will consist of a 192 nearly identical 2 megajoule capacitor storage banks driving 7680 two meter long flashlamps. A fully integrated single-module test facility was completed in August of 2000 at LLNL. The purpose to the Test Facility is to conduct Reliability and Maintainability (RAM) testing of a true ''First Article'' system (built to the final drawing package as opposed to a prototype). The test facility can be fired once every ten minutes with a total peak output current of 580kA with a pulse width of 400us. To date over 4000 full power shots have been conducted at this facility.

Continuous melting of phosphate laser glass is now being used for the first time to prepare meter-scale amplifier optics for megajoule lasers. The scale-up to continuous melting from the previous one-at-a-time ''discontinuous'' batch process has allowed for the production of glass at rates more than 20 times faster, 5 times cheaper, and with 2-3 times better optical quality. Almost 8000 slabs of laser glass will be used in high-energy, high-peak-power laser systems that are being designed and built for fusion energy research. The success of this new continuous melting process, which is a result of a six year joint R&D program between government and industry, stems from numerous technical advances which include (1) dehydroxylating the glass to concentrations less than {approx}100 ppm OH; (2) minimizing damage-causing Pt-inclusions; (3) preventing glass fracture; (4) minimizing impurities such as Cu and Fe to <20 ppm; (5) improving forming methods to get high optical homogeneity glass; and (6) developing large aperture quality assurance tools to verify properties of the glass.

The immobilization of plutonium-containing wastes into stable solid compositions is one of the problems to be solved in the disposal of radioactive wastes. Research efforts on the selection, preparation with the use of the cold crucible induction melter (CCIM) technology, and investigation of materials that are most suitable for immobilizing plutonium-containing wastes of different origin have been carried out at the All-Russian Scientific Research Institute of Inorganic Materials (VNIINM) and the Institute of the Geology of Ore Deposits, Petrography, Mineralogy, and Geochemistry (IGEM), Russian Academy of Sciences within the framework of agreements with Lawrence Livermore National Laboratory (LLNL, USA) regarding material and technical support. This paper presents the data on the synthesis of cerium-, uranium-, and plutonium-containing materials based on borobasalt, pyroxene, and andradite compositions in the muffle furnace and by the CCIM method. Compositions containing up to 15-18 wt% cerium oxide, 8-11 wt% uranium oxide, and 4.6-5.7 wt% plutonium oxide were obtained in laboratory facilities installed in glove boxes. Comparison studies of the materials synthesized in the muffle furnace and CCIM demonstrate the advantages of using the CCIM method. The distribution of components in the materials.

This paper describes design and operation of the flashlamp test system, used to evaluate the primary laser flashlamps on the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in Livermore, California. The tester delivers repetitive high voltage pulses to a series pair of flashlamps at levels closely simulating those encountered in normal operation. Each lamp pair is subjected to a pre-ionization and main pulse shot sequence, with two minute intervals between shots. This capability allows the manufacturer to test and evaluate the flashlamps for infant mortality and longevity before delivery to NIF. All operations are under computer control with fully automated test and data acquisition capabilities requiring minimal operator input. The system is designed to operate continuously. Typical pre-ionization and main pulse outputs are: (1) Pre-ionization Pulse--V{sub chg} = 27kV, I{sub peak} = 3kA, E = 2.4kJ; Pulse Width--(10%-90%) - 200us; Main Pulse--V{sub chg} = 23kV, I{sub peak} - 24kA, E - 78.6kJ; and Pulse Width--(10%-90%) - 350us.

Optical coatings are a crucial part of the pulse trapping and extraction in the NIF multipass amplifiers. Coatings also steer the 192 beams from four linear arrays to four converging cones entering the target chamber. There are a total of 1600 physical vapor deposited coatings on NIF consisting of 576 mirrors within the multipass cavity, 192 polarizers that work in tandem with a Pockels cell to create an optical switch, and 832 transport mirrors. These optics are of sufficient size so that they are not aperture-limiting for the 40-cm x 40 cm beams over an incident range of 0 to 56.4 degrees. These coatings must withstand laser fluences up to 25 J/cm{sup 2} at 1053 nm (1 {omega}) and 3-ns pulse length and are the 1{omega} fluence-limiting component on NIF. The coatings must have a minimal impact on the beam wavefront and phase to maintain beam focusability, minimize scattered loss, and minimize nonlinear damage mechanisms. This is achieved by specifications ranging from <50 MPa coating stress, <1% coating nonuniformity, <4{angstrom} RMS surface roughness, and a PSD specification to control the amplitude of periodic spatial frequencies. Finally, the primary mission of optical coatings is efficient beam steering so reflection and transmission …

Temperature measurement is one of the grand challenges still facing experimental shock physics. A shock experiment fundamentally measures E({sigma}{sub x}, {var_epsilon}{sub 11}) which is an incomplete equation of state since temperature (or entropy) remains unspecified. Ideally, one would like to experimentally determine a free energy F(T, {var_epsilon}{sub ij}) from which all other thermo-mechanical properties might be derived. In practice, temperature measurement would allow direct comparison with theory/simulation since T and {var_epsilon}{sub 11} are in most theories the underlying variables. Temperature is a sensitive measure of energy partitioning, knowledge of which would increase our understanding phase boundaries and thermally activated processes (such as chemical reactivity (including dissociation and ionization)). Temperature measurement would also allow a thermodynamically consistent coupling of hydrodynamic equations of state to the material's constitutive (deformation) behavior. The measurement of the temperature of a material that has undergone severe strains at small time-scales is extremely difficult, and we are developing a method using infrared reflectance and pyrometry. The emitted power from a warm surface is measured over a range of wavelengths using a multi-channel IR detector with a response time of {approx}0.1 {micro}s. Each channel of the detector passes the radiation from a selected wavelength interval into a detector. …

The Lawrence Berkeley National Laboratory (LBNL) has been developing sensors for the pulp and paper industry that uses a magnetic field. The applications for magnetic sensors that have studied include (1) sensors for the measurement of the water and ice content of wood chips entering the pulping mill, (2) sensors for measuring the water content and other constituents of the black liquor leaving the paper digester, and (3) sensors for measuring paper thickness and water content as the paper is being processed. These tasks can be done using nuclear magnetic resonance (NMR). The magnetic field used for doing the NMR can come from either permanent magnets or superconducting magnets. The choice of the magnet is dependent on a number of factors, which include the size of the sample and field strength needed to do the sensing task at hand. This paper describes some superconducting magnet options that can be used in the pulp and paper industry.

Schwertmannite is a poorly crystallized iron oxyhydroxidewith essential structural sulfate that can be a major component in acidmine drainage environments. Original characterization work concluded thatthe sulfate was largely contained within tunnels of an orderedakaganeite-like structure based on powder XRD, analysis of IR spectra,and sulfate extraction procedures [1]. Since the original description,problems have emerged with the nature of the tunnel sulfate, and with theinterpretation of the IR spectra. Other related work has shown that it isnow possible to determine sulfate-iron oxide inner sphere bindingunambiguously from the S K-edge XANES spectrum. Hence a reassessment ofthe evidence for the original schwertmannite structure was deemednecessary and timely.

A large-scale vadose zone-groundwater bioremediationdemonstration was conducted at the Savannah River Site (SRS) by injectingseveral types of gases (ambient air, methane, and nitrous oxide andtriethyl phosphate mixtures) through a horizontal well in the groundwaterat a 175 ft depth. Simultaneously, soil gas was extracted through aparallel horizontal well in the vadose zone at a 80 ft depth Monitoringrevealed a wide range of spatial and temporal variations ofconcentrations of VOCs, enzymes, and biomass in groundwater and vadosezone monitoring boreholes over the field site. One of the powerful modernapproaches to analyze uncertain and imprecise data chemical data is basedon the use of methods of fuzzy systems modeling. Using fuzzy modeling weanalyzed the spatio-temporal TCE and PCE concentrations and methanotrophdensities in groundwater to assess the effectiveness of differentcampaigns of air stripping and bioremediation, and to determine the fuzzyrelationship between these compounds. Our analysis revealed some detailsabout the processes involved in remediation, which were not identified inthe previous studies of the SRS demonstration. We also identified somefuture directions for using fuzzy systems modeling, such as theevaluation of the mass balance of the vadose zone - groundwater system,and the development of fuzzy-ruled methods for optimization of managingremediation activities, predictions, and risk assessment.

Algorithms for the treatment of special positions in 3-dimensional crystallographic space groups are presented. These include an algorithm for the determination of the site-symmetry group given the coordinates of a point, an algorithm for the determination of the exact location of the nearest special position, an algorithm for the assignment of a Wyckoff letter given the site-symmetry group, and an alternative algorithm for the assignment of a Wyckoff letter given the coordinates of a point directly. All algorithms are implemented in ISO C++ and are integrated into the Computational Crystallography Toolbox. The source code is freely available.

Chassis dynamometer tests were performed on 7 light heavy-duty diesel trucks comparing the emissions of a California diesel fuel with emissions from 4 other fuels: ARCO EC-diesel (EC-D) and three 20% biodiesel blends (1 yellow grease and 2 soy-based). The EC-D and the yellow grease biodiesel blend both showed significant reductions in THC and CO emissions over the test vehicle fleet. EC-D also showed reductions in PM emission rates. NOx emissions were comparable for the different fuel types over the range of vehicles tested. The soy-based biodiesel blends did not show significant or consistent emissions differences over all test vehicles. Total carbon accounted for more than 70% of the PM mass for 4 of the 5 sampled vehicles. Elemental and organic carbon ratios varied significantly from vehicle-to-vehicle but showed very little fuel dependence. Inorganic species represented a smaller portion of the composite total, ranging from 0.2 to 3.3% of the total PM. Total PAH emissions ranged from approximately 1.8 mg/mi to 67.8 mg/mi over the different vehicle/fuel combinations representing between 1.6 and 3.8% of the total PM mass.

An improved Thermoelectric Generator (TEG) for the Heavy Duty Class Eight Diesel Trucks is under development at Hi-Z Technology. The current TEG is equipped with the improved HZ-14 Thermoelectric module, which features better mechanical properties as well as higher electric power output. Also, the modules are held in place more securely. The TEG is comprised of 72 TE modules, which are capable of producing 1kW of electrical power at 30 V DC during nominal engine operation. Currently the upgraded generator has completed testing in a test cell and starting from August 2001 will be tested on a Diesel truck under typical road and environmental conditions. It is expected that the TEG will be able to supplement the existing shaft driven alternator, resulting in significant fuel saving, generating additional power required by the truck�s accessories. The electronic and thermal properties of bulk materials are altered when they are incorporated into quantum wells. Two-dimensional quantum wells have been synthesized by alternating layers of B4C and B9C in one system and alternating layers of Si and Si0.8Ge0.2 in another system. Such nanostructures are being investigated as candidate thermoelectric materials with high figures of merit (Z). The predicted enhancement is attributed to the confined …

A combination of catalysts is used together with nonthermal plasma in simulated diesel exhaust, while the gas temperature is varied. The catalysts both store and convert pollutants. As a result, pollutant concentrations during temperature ramps are different than those at steady state conditions. The data are presented for plasma followed by BaY, alumina, and Pt catalysts in simulated exhaust. When temperature ramps from high to low, apparent NOx conversion is quite high. However, when temperature is ramped from low to high, lower apparent conversions are seen. In a typical test cycle, average NOx conversion between 100 and 400 C is 60%. Peak conversion during the down ramp is over 90%, and minimum conversion during the up ramp is 30%. The composition of the effluent gas also varies during the temperature cycle. Intermediates such as methyl nitrate and hydrogen cyanide are not present following the combination of catalysts.

The need for active regeneration of diesel particulate filters and the advantages of microwave assisted regeneration are discussed. The current study has multiple objectives, which include developing a microwave assisted particulate filter regeneration system for future generation light-duty diesel applications, including PNGV type applications. A variable power 2.0 kW microwave system and a tuned waveguide were employed. Cavity geometry is being optimized with the aid of computational modeling and temperature measurements during microwave heating. A wall-flow ceramic-fiber filter with superior thermal shock resistance, high filtration efficiency, and high soot capacity was used. The microwave assisted particulate filter regeneration system has operated for more than 100 hours in an engine test-cell with a 5.9-liter diesel engine with automated split exhaust flow and by-pass flow capabilities. Filter regeneration was demonstrated using soot loads up to 10 g/liter and engine exhaust at idling flow rates as the oxygen source. A parametric study to determine the optimal combination of soot loading, oxidant flow rate, microwave power and heating time is underway. Preliminary experimental results are reported.

Pollution from diesel engines is a significant part of our nation's air-quality problem. Even under the more stringent standards for heavy-duty engines set to take effect in 2004, these engines will continue to emit large amounts of nitrogen oxides and particulate matter, both of which affect public health. To address this problem, the Idaho National Engineering and Environmental Laboratory (INEEL) invented a self-cleaning, high temperature, cermet filter that reduces heavy-duty diesel engine emissions. The main advantage of the INEEL cermet filter, compared to current technology, is its ability to destroy carbon particles and NOx in diesel engine exhaust. As a result, this technology is expected to improve our nation's environmental quality by meeting the need for heavy-duty diesel engine emissions control. This paper describes the cermet filter technology and the initial research and development effort.Diesel engines currently emit soot and NOx that pollute our air. It is expected that the U.S. Environmental Protection Agency (EPA) will begin tightening the regulatory requirements to control these emissions. The INEEL's self-cleaning, high temperature cermet filter provides a technology to clean heavy-duty diesel engine emissions. Under high engine exhaust temperatures, the cermet filter simultaneously removes carbon particles and NOx from the exhaust gas. The …

The proposed 21st Century Truck program selected three truck classes for focused analysis. On the basis of gross vehicle weight (GVW) classification, these were Class 8 (representing heavy), Class 6 (representing medium), and Class 2b (representing light). To develop and verify these selections, an evaluation of fuel use of commercial trucks was conducted, using data from the 1997 Vehicle Inventory and Use Survey (VIUS). Truck fuel use was analyzed by registered GVW class, and by body type.

This presentation is a summary of the current research activities on fuels and lubricants in the Multi-discipline Tribology group and the engine test group in the Combustion Laboratory of the Pennsylvania State University. The progress areas discussed in this summary include those found in Table 1. Table 1. RESEARCH AREAS: Diesel Engine Emission Reduction; Oxygenated Fuels; Improved Friction Fuels; Vegetable Oil Lubricants; Extended Drain Lubricants; Effect of Chemical Structure on Friction and Wear. The research is of interest either directly or indirectly to the goal of this workshop, diesel engine emissions reduction. The current projects at Penn State in the areas listed above will be discussed.

The Drift Scale Test (DST) now underway at Yucca Mountain has been simulated using a Drift Scale Distinct Element (DSDE) model. Simulated deformations show good agreement with field deformation measurements. Results indicate most fracture deformation is located above the crown of the Heated Drift. This work is part of the model validation effort for the DSDE model, which is used to assess thermal-mechanical effects on the hydrology of the rock mass surrounding a potential repository.

In today's competitive and highly litigious world, it is critical that any laboratory generating data for the environmental and allied industries have a world-class Quality Assurance Program. This Plan must conform to the requirements of every agency and client with whom the lab does business. The goal of such a program is data defensibility; i.e., data validity. Data (usually qualitative analyte [compound or element] identifications and quantitative numerical results) are the end results of nearly all analytical laboratory processes, and the source of revenue. Clients pay for results. The clients expect the results to be accurate, precise, and repeatable. If their data has to go to court, the laboratory will be called upon to defend the accuracy and precision of their work. Without a strong QA program, this will be impossible. The potential implications and repercussions of non-defensible lab data are far-reaching and very costly in terms of loss of future revenues and in legal judgments.

This cooperative program between the DOE Office of Heavy Vehicle Technology and Caterpillar, Inc. is aimed at demonstrating electric turbocompound technology on a Class 8 truck engine. This is a lab demonstration program, with no provision for on-truck testing of the system. The goal is to demonstrate the level of fuel efficiency improvement attainable with the electric turbocompound system. Also, electric turbocompounding adds an additional level of control to the air supply which could be a component in an emissions control strategy.

This paper presents a review of the Thermal DeNOx process with respect to its application to control of NOx emissions from diesel engines. The chemistry of the process is discussed first in empirical and then theoretical terms. Based on this discussion the possibilities of applying the process to controlling NOx emissions from diesel engines is considered. Two options are examined, modifying the requirements of the chemistry of the Thermal DeNOx process to suit the conditions provided by diesel engines and modifying the engines to provide the conditions required by the process chemistry. While the former examination did not reveal any promising opportunities, the latter did. Turbocharged diesel engine systems in which the turbocharger is a net producer of power seem capable of providing the conditions necessary for NOx reduction via the Thermal DeNOx reaction.

Recent DOE-OHVT studies show that diesel emissions and fuel consumption can be greatly reduced at truck stops by switching from engine idle to auxiliary-fired heaters. Brookhaven National Laboratory (BNL) has studied high performance diesel burner designs that address the shortcomings of current low fire-rate burners. Initial test results suggest a real opportunity for the development of a truly advanced truck heating system. The BNL approach is to use a low pressure, air-atomized burner derived form burner designs used commonly in gas turbine combustors. This paper reviews the design and test results of the BNL diesel fueled cabin heater. The burner design is covered by U.S. Patent 6,102,687 and was issued to U.S. DOE on August 15, 2000.The development of several novel oil burner applications based on low-pressure air atomization is described. The atomizer used is a pre-filming, air blast nozzle of the type commonly used in gas turbine combustion. The air pressure used can b e as low as 1300 Pa and such pressure can be easily achieved with a fan. Advantages over conventional, pressure-atomized nozzles include ability to operate at low input rates without very small passages and much lower fuel pressure requirements. At very low firing rates the …

Diesel engines are the most realistic technology to achieve a major improvement in fuel economy in the next decade. In the US light truck market, i.e. Sport Utility Vehicles , pick-up trucks and mini-vans, diesel engines can more than double the fuel economy of similarly rated spark ignition (SI) gasoline engines currently in these vehicles. These new diesel engines are comparable to the SI engines in noise levels and 0 to 60 mph acceleration. They no longer have the traditional ''diesel smell.'' And the new diesel engines will provide roughly twice the service life. This is very significant for resale value which could more than offset the initial premium cost of the diesel engine over that of the SI gasoline engine. So why are we not seeing more diesel engine powered personal vehicles in the U.S.? The European auto fleet is comprised of a little over 30 percent diesel engine powered vehicles while current sales are about 50 percent diesel. In France, over 70 percent of the luxury class cars i.e. Mercedes ''S'' Class, BMW 700 series etc., are sold with the diesel engine option selected. Diesel powered BMW's are winning auto races in Germany. These are a typical of …