Orbits that are chaotic will tend to phase-mix exponentially through their accessible phase space. This phenomenon, commonly called ''chaotic mixing'', stands in marked contrast to phase mixing of regular orbits. It is inherently irreversible, and thus its associated e-folding time scale sets a condition on any process envisioned for emittance compensation. Accordingly, two questions arise. First, under what conditions does chaotic mixing manifest itself in beams? Second, when it is active, over what time scale does it operate? The work described here is part of an ongoing effort to answer these questions.

The goal of the U.S. Department of Energy (DOE) Clean Coal Technology Program (CCT) is to furnish the energy marketplace with a number of advanced, more efficient, and environmentally responsible coal utilization technologies through demonstration projects. These projects seek to establish the commercial feasibility of the most promising advanced coal technologies that have developed beyond the proof-of-concept stage. This document serves as a DOE post-project assessment (PPA) of a project selected in CCT Round IV, the Wabash River Coal Gasification Repowering (WRCGR) Project, as described in a Report to Congress (U.S. Department of Energy 1992). Repowering consists of replacing an existing coal-fired boiler with one or more clean coal technologies to achieve significantly improved environmental performance. The desire to demonstrate utility repowering with a two-stage, pressurized, oxygen-blown, entrained-flow, integrated gasification combined-cycle (IGCC) system prompted Destec Energy, Inc., and PSI Energy, Inc., to form a joint venture and submit a proposal for this project. In July 1992, the Wabash River Coal Gasification Repowering Project Joint Venture (WRCGRPJV, the Participant) entered into a cooperative agreement with DOE to conduct this project. The project was sited at PSI Energy's Wabash River Generating Station, located in West Terre Haute, Indiana. The purpose of this …

The objective of this contract was to design, synthesize, and characterize thickening agents for dense carbon dioxide and to evaluate their solubility and viscosity-enhancing potential in CO2.

Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. Additional field tests have been performed in this quarter. The development of the data interpretation methodology and other related tasks are still continuing.

In this quarter we focus on the membrane synthesis via interphase impregnation and slip casting. The slip casting method shows very promising. A well-organized hydrotalcite layer has been deposited on the porous ceramic substrate. Under SEM examination, few defects were recognized. In addition, its particle size in the range of {approx}500{angstrom} is comparable to our existing Al{sub 2}O{sub 3} membrane with 100{angstrom} pore size. This membrane could be qualified for post-treatment with CVD/I to seal the opening to become a CO{sub 2}-affinity membrane. On the other hand, the hydrotalcite membrane prepared via impregnation requires further refinement. After 4th impregnation defects in the range of 0.2 micron were observed under SEM examination, likely due to the incomplete coverage. In the next quarter, we will improve the in-situ technique to overcome this problem.

Roof bolting is the most popular method for underground openings in the mining industry, especially in the bedded deposits such as coal, potash, salt etc. In fact, all U.S. underground coal mine entries are roof-bolted as required by law. However, roof falls still occur frequently in the roof bolted entries. The two possible reasons are: the lack of knowledge of and technology to detect the roof geological conditions in advance of mining, and lack of roof bolting design criteria for modern roof bolting systems. This research is to develop a method for predicting the roof geology and stability condition in real time during roof bolting operation. Based on such information, roof bolting design criteria for modern roof bolting systems will be developed for implementation in real time. More laboratory tests have been performed in this quarter. The analysis performed on the testing data showed: (1) abnormal rotational accelerations can be used as the indicator of the rock interfaces, and (2) the sharp drops of drilling thrust and torque agree well with the locations of fractures.

A major research goal of the National Spherical Torus Experiment is establishing long-pulse, high-beta, high-confinement operation and its physics basis. This research has been enabled by facility capabilities developed over the last two years, including neutral-beam (up to 7 MW) and high-harmonic fast-wave heating (up to 6 MW), toroidal fields up to 6 kG, plasma currents up to 1.5 MA, flexible shape control, and wall preparation techniques. These capabilities have enabled the generation of plasmas with <beta {sub T}> up to 35%. Normalized beta values often exceed the no wall limit, and studies suggest that passive wall mode stabilization is enabling this for broad pressure profiles characteristic of H-mode plasmas. The viability of long, high bootstrap-current fraction operations has been established for ELMing H-mode plasmas with toroidal beta values in excess of 15% and sustained for several current relaxation times. Improvements in wall conditioning and fueling are likely contributing to a reduction in H-mode power thresholds. Electron thermal conduction is the dominant thermal loss channel in auxiliary-heated plasmas examined thus far. High-harmonic fast-wave (HHFW) effectively heats electrons, and its acceleration of fast beam ions has been observed. Evidence for HHFW current drive is by comparing of the loop voltage evolution …

This report describes work performed during the second year of the project ''Modified reverse osmosis system for treatment of produced waters.'' We performed two series of reverse osmosis experiments using very thin bentonite clay membranes compacted to differing degrees. The first series of 10 experiments used NaCl solutions with membranes that ranged between 0.041 and 0.064mm in thickness. Our results showed compaction of such ultra-thin clay membranes to be problematic. The thickness of the membranes was exceeded by the dimensional variation in the machined experimental cell and this is believed to have resulted in local bypassing of the membrane with a resultant decrease in solute rejection efficiency. In two of the experiments, permeate flow was varied as a percentage of the total flow to investigate results of changing permeate flow on solute rejection. In one experiment, the permeate flow was varied between 2.4 and 10.3% of the total flow with no change in solute rejection. In another experiment, the permeate flow was varied between 24.6 and 52.5% of the total flow. In this experiment, the solute rejection rate decreased as the permeate occupied greater fractions of the total flow. This suggests a maximum solute rejection efficiency for these clay membranes …

The numerical simulation of the driving beams in a heavy ion fusion power plant is a challenging task, and, despite rapid progress in computer power, one must consider the use of the most advanced numerical techniques. One of the difficulties of these simulations resides in the disparity of scales in time and in space which must be resolved. When these disparities are in distinctive zones of the simulation region, a method which has proven to be effective in other areas (e.g. fluid dynamics simulations) is the Adaptive-Mesh-Refinement (AMR) technique. We follow in this article the progress accomplished in the last few months in the merging of the AMR technique with Particle-In-Cell (PIC) method. This includes a detailed modeling of the Lampel-Tiefenback solution for the one-dimensional diode using novel techniques to suppress undesirable numerical oscillations and an AMR patch to follow the head of the particle distribution. We also report new results concerning the modeling of ion sources using the axisymmetric WARPRZ-AMR prototype showing the utility of an AMR patch resolving the emitter vicinity and the beam edge.

The goal of the project is to enable plant operators to detect with high sensitivity and reliability the onset of decalibration drifts in all of the instrumentation used as input to the reactor heat balance calculations. To achieve this objective, the collaborators developed and implemented at DBNPS an extension of the Multivariate State Estimation Technique (MSET) pattern recognition methodology pioneered by ANAL. The extension was implemented during the second phase of the project and fully achieved the project goal.

Roofs that have high solar reflectance (high ability to reflect sunlight) and high thermal emittance (high ability to radiate heat) tend to stay cool in the sun. The same is true of low-emittance roofs with exceptionally high solar reflectance. Substituting a cool roof for a noncool roof tends to decrease cooling electricity use, cooling power demand, and cooling-equipment capacity requirements, while slightly increasing heating energy consumption. Cool roofs can also lower the ambient air temperature in summer, slowing ozone formation and increasing human comfort. DOE-2.1E building energy simulations indicate that use of a cool roofing material on a prototypical California nonresidential building with a low-sloped roof yields average annual cooling energy savings of approximately 300 kWh/1000 ft2 [3.2 kWh/m2], average annual natural gas deficits of 4.9 therm/1000 ft2 [5.6 MJ/m2], average source energy savings of 2.6 MBTU/1000 ft2 [30 MJ/m2], and average peak power demand savings of 0. 19 kW/1000 ft2 [2.1 W/m2]. The 15-year net present value (NPV) of energy savings averages $450/1000 ft2 [$4.90/m2] with time dependent valuation (TDV), and $370/1000 ft2 [$4.00/m2] without TDV. When cost savings from downsizing cooling equipment are included, the average total savings (15-year NPV + equipment savings) rises to $550/1000 ft2 [$5.90/m2] …

A four-fold increase in the conversion of thermal electron-Bernstein waves (EBW) to the extraordinary mode (X-mode) was measured when the density scale length (L subscript ''n'') was progressively shortened by a local Boron nitride limiter in the scrape-off of an ohmically heated National Spherical Torus Experiment (NSTX) plasma [M. Ono, S. Kaye, M. Peng, et al., Proceedings 17th IAEA Fusion Energy Conference (IAEA, Vienna, Austria, 1999), Vol. 3, p. 1135]. The maximum conversion efficiency approached 50% when L subscript ''n'' was reduced to 0.7 cm, in agreement with theoretical predictions that used locally measured L subscript ''n''. Calculations indicate that it is possible to establish L subscript ''n'' < 0.3 cm with a local limiter, a value predicted to attain approximately 100% EBW conversion to the X-mode in support of proposed EBW heating and current drive scenarios.

A range of effects may make fast ion confinement in spherical tokamaks worse than in conventional aspect ratio tokamaks. Data from neutron detectors, a neutral particle analyzer, and a fast ion loss diagnostic on the National Spherical Torus Experiment (NSTX) indicate that neutral beam ion confinement is consistent with classical expectations in quiescent plasmas, within the {approx}25% errors of measurement. However, fast ion confinement in NSTX is frequently affected by magnetohydrodynamic (MHD) activity, and the effect of MHD can be quite strong.

Microorganisms have the capacity to modify iron oxides during anaerobic respiration. When the dissimilatory sulfate-reducing bacterium Desulfovibrio desulfuricans G20 respires soluble sulfate during colonization of the solid-phase iron oxide hematite, the sulfide product reacts with the iron to produce the insoluble iron sulfide, pyrrhotite. When soluble uranium is present as uranyl ion, these microorganisms reduce the U(VI) to U(IV) as insoluble uraninite on the hematite surface. There is also evidence that a stable form of U is produced under these conditions that displays an oxidation state between U(VI) and U(iv). The dissimilatory iron reducing bacterium, Shewanella oneidensis MR1 can utilize insoluble hematite as the sole electron acceptor for anaerobic respiration during growth and biofilm development on the mineral. The growth rate, maximum cell density and detachment rate for this bacterium are significantly greater on hematite than on magnetite (111) and (100). The difference could not be attributed to iron site density in the iron oxide. A gene (ferA) encoding a c-tyoe cytochrome involved in dissimulatory iron reduction in the bacterium Geobacter sulfurreducens was completed sequenced and characterized. The sequence information was used to develop an in-situ reverse transcriptase polymerase chain reaction assay that could detect expression of the gene during …

The Ernest Orlando Lawrence Berkeley National Laboratory (Berkeley Lab or LBNL) is a multi-program national research facility operated by the University of California for the Department of Energy (DOE). As an integral element of DOE's National Laboratory System, Berkeley Lab supports DOE's missions in fundamental science, energy resources, and environmental quality. Berkeley Lab programs advance four distinct goals for DOE and the nation: (1) To perform leading multidisciplinary research in the computing sciences, physical sciences, energy sciences, biosciences, and general sciences in a manner that ensures employee and public safety and protection of the environment. (2) To develop and operate unique national experimental facilities for qualified investigators. (3) To educate and train future generations of scientists and engineers to promote national science and education goals. (4) To transfer knowledge and technological innovations and to foster productive relationships among Berkeley Lab's research programs, universities, and industry in order to promote national economic competitiveness. This is the annual report on Laboratory Directed Research and Development (LDRD) program for FY01.

Indoor exposure to particles of outdoor origin constitutes an important exposure pathway. We conducted an intensive set of indoor particle measurements in an unoccupied house under differing operating conditions. Real-time measurements were conducted both indoors and outdoors, including PM2.5 nitrate, sulfate, and carbon. Because the time-scale of the fluctuations in outdoor particle concentrations and meteorological conditions are often similar to the time constant for building air exchange, a steady state concentration may never be reached. The time-series experimental data were used to determine the effect of changes in air exchange rate and indoor/outdoor temperature and relative humidity differences on indoor particle concentrations. A multivariate regression was performed to investigate the difference between measured indoor concentrations and results from a simple time-dependent physical model. Environmental conditions had a significant effect on indoor concentrations of all three PM2.5 species, but did not explain all of the model variation.

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GaN has received much attention over the past few years because of several new applications, including light emitting diodes, blue laser diodes and high-power microwave transistors. One of the biggest problems is a high density of structural defects, mostly dislocations, due to a lack of a suitable lattice-matched substrate since bulk GaN is difficult to grow in large sizes. Transmission Electron Microscopy (TEM) has been applied to study defects in plan-view and cross-sections on samples prepared by conventional techniques such as mechanical thinning and precision ion milling. The density of dislocations close to the sample surface of a 1 mm-thick HVPE sample was in the range of 3x109 cm-2. All three types of dislocations were present in these samples, and almost 50 percent were screw dislocations. Our studies suggest that the core structure of screw dislocations in the same material might differ when the material is grown by different methods.

This report details results from work conducted under the grant entitled ''Scalable Dynamic Mesh Algorithms and Software'' for the period September 1, 1998 to November 30, 2001.

An economical and environment-friendly ironmaking process based on heating the chemiexecy self-sufficient green balls of iron ore and coal in a hearth furnace is being developed with financial support from AISI members and DOE. DRI, which is hot (1400 C), dense (3.2 g/cm) and of high degree of metallization (95%), has been produced in laboratory and in a pilot plant in Genoa, Italy. Products of such quality have been made from American and Brazilian ores, BOF sludge, EAF dust/BOF sludge mixtures and millscale. The removal of zinc and lead from green balls by this process is essentially complete. In comparison with typical blast furnace operation, the new technology with a melter would have a lower total coal rate by 200kg.THM. The elimination of cokemaking and high temperature agglomeration steps, and a simpler gas handling system would lead to lower capital and operating costs. In comparison with commercial RHF practice it is different in atmosphere (fully oxidized at 1600 to 1650 C), in bed height (120 mm instead of 20-25 mm) and in pellet composition (much less coal but of higher VM). The combined effect leads to three times higher furnace productivity, lower coal consumption and superior DRI quality. The risk …

As cleanup workers excavate pits and tear down buildings at the Fernald site in southwest Ohio, site ecologists are working side-by-side to create thriving wetlands and develop the early stages of forest, prairie, and savanna ecosystems to restore natural resources that were impacted by years of site operations. In 1998, the U.S. Department of Energy-Fernald Office (DOE-FN) and its cleanup contractor, Fluor Fernald, Inc., initiated several ecological restoration projects in perimeter areas of the site (e.g., areas not used for or impacted by uranium processing or waste management). The projects are part of Fernald's final land use plan to restore natural resources over 904 acres of the 1,050-acre site. Pete Yerace, the DOE-FN Natural Resource Trustee representative is working with the Fernald Natural Resource Trustees in an oversight role to resolve the state of Ohio's 1986 claim against DOE for injuries to natural resources. Fluor Fernald, Inc., and DOE-FN developed the ''Natural Resource Restoration Plan'', which outlines 15 major restoration projects for the site and will restore injured natural resources at the site. In general, Fernald's plan includes grading to maximize the formation of wetlands or expanded floodplain, amending soil where topsoil has been removed during excavation, and establishing native …

Injection of Lower Hybrid Heating and Current Drive (LHCD) into the current ramp-up phase of JET [Joint European Torus] discharges can produce extremely reversed q-profiles characterized by a core region of near zero current density (within Motional Stark Effect diagnostic measurement errors). Non-inductive, off-axis co-current drive induces a back electromotive force inside the non-inductive current radius that drives a negative current in the plasma core. The core current density does not go negative, although current diffusion calculations indicate that there is sufficient LHCD to cause this. The clamping of the core current density near zero is consistent with n=0 reconnection events redistributing the core current soon after it goes negative. This is seen in reduced MHD simulations and in nonlinear resistive MHD simulations which predict that these discharges undergo n=0 reconnection events that clamp the core current near zero.

Refinery processes that convert heavy oils to lighter distillate fuels require heating for distillation, hydrogen addition or carbon rejection (coking). Efficiency is limited by the formation of insoluble carbon-rich coke deposits. Heat exchangers and other refinery units must be shut down for mechanical coke removal, resulting in a significant loss of output and revenue. When a residuum is heated above the temperature at which pyrolysis occurs (340 C, 650 F), there is typically an induction period before coke formation begins (Magaril and Aksenova 1968, Wiehe 1993). To avoid fouling, refiners often stop heating a residuum before coke formation begins, using arbitrary criteria. In many cases, this heating is stopped sooner than need be, resulting in less than maximum product yield. Western Research Institute (WRI) has developed innovative Coking Index concepts (patent pending) which can be used for process control by refiners to heat residua to the threshold, but not beyond the point at which coke formation begins when petroleum residua materials are heated at pyrolysis temperatures (Schabron et al. 2001). The development of this universal predictor solves a long standing problem in petroleum refining. These Coking Indexes have great potential value in improving the efficiency of distillation processes. The Coking …

This report describes the tasks performed and the progress made during Phase 2 of the DOE-NERI project number 99-119 entitled Automatic Development of Highly Reliable Control Architecture for Future Nuclear Power Plants. This project is a collaboration effort between the Oak Ridge National Laboratory (ORNL), The University of Tennessee, Knoxville (UTK) and the North Carolina State University (NCSU). ORNL is the lead organization and is responsible for the coordination and integration of all work.