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Alternatives to conventional diesel fuel-some potential implications of California's TAC decision on diesel particulate.

Description: Limitations on the use of petroleum-based diesel fuel in California could occur pursuant to the 1998 declaration by California's Air Resources Board (CARB) that the particulate matter component of diesel exhaust is a carcinogen, therefore a toxic air contaminant (TAC) subject to provisions of the state's Proposition 65. It is the declared intention of CARB not to ban or restrict diesel fuel, per se, at this time. Assuming no total ban, Argonne National Laboratory (ANL) explored two feasible ''mid-course'' strategies. (1) Increased penetration of natural gas and greater gasoline use in the transportation fuels market, to the extent that some compression-ignition (CI) applications revert to spark-ignition (SI) engines. (2) New specifications requiring diesel fuel reformulation based on exhaust products of individual diesel fuel constituents. Each of these alternatives results in some degree of (conventional) diesel displacement. In the first case, diesel fuel is assumed admissible for ignition assistance as a pilot fuel in natural gas (NG)-powered heavy-duty vehicles, and gasoline demand in California increases by 32.2 million liters per day overall, about 21 percent above projected 2010 baseline demand. Natural gas demand increases by 13.6 million diesel liter equivalents per day, about 7 percent above projected (total) consumption level. In the second case, compression-ignition engines utilize substitutes for petroleum-based diesel having similar ignition and performance properties. For each case we estimated localized air emission plus generalized greenhouse gas and energy changes. Economic implications of vehicle and engine replacement were not evaluated.
Date: August 10, 1999
Creator: Eberhardt, J. J.; Rote, D. M.; Saricks, C. L. & Stodolsky, F.
Partner: UNT Libraries Government Documents Department

Microstructural development in waste form alloys cast from irradiated cladding residual from the electrometallurgical treatment of EBR-II spent fuel.

Description: A metallic waste form alloy that consists primarily of stainless steel and zirconium is being developed by Argonne National Laboratory to contain metallic waste constituents that are residual from an electrometallurgical treatment process for spent nuclear fuel. Ingots have been cast in an induction furnace in a hot cell using actual, leftover, irradiated, EBR-II cladding hulls treated in an electrorefiner. The as-cast ingots have been sampled using a core-drilling and an injection-casting technique. In turn, generated samples have been characterized using chemical analysis techniques and a scanning electron microscope equipped with energy dispersive and wavelength-dispersive spectrometers. As-cast ingots contain the predicted concentration levels of the various constituents, and most of the phases that develop are analogous to those for alloys generated using non-radioactive surrogates for the various fission products.
Date: June 10, 1999
Creator: Keiser, D. D., Jr.
Partner: UNT Libraries Government Documents Department

Master plate production for the tile calorimeter extended barrel modules.

Description: Approximately 41,000 master plates (Fig. 1) are required for the Extended Barrel Hadronic Calorimeter for the ATLAS experiment at the LHC. Early in the R&D program associated with the detector, it was recognized that the fabrication of these steel laminations was a significant issue, both in terms of the cost to produce these high precision formed plates, as well as the length of time required to produce all plates for the calorimeter. Two approaches were given serious consideration: laser cutting and die stamping. The Argonne group was a strong supporter of the latter approach and in late 1995 initiated an R&D program to demonstrate the feasibility and cost effectiveness of die stamping these plates by constructing a die and stamping approximately 2000 plates for use in construction of three full size prototype modules. This was extremely successful and die stamping was selected by the group for production of these plates. When the prototype die was constructed it was matched to the calorimeter envelope at that time. This subsequently changed. However with some minor adjustments in the design envelope and a small compromise in terms of instrumented volume, it became possible to use this same die for the production of all master plates for the Tile Calorimeter. Following an extensive series of discussions and an evaluation of the performance of the stamping presses available to our collaborators in Europe, it was decided to ship the US die to CERN for use in stamping master plates for the barrel section of the calorimeter. This was done under the supervision of CERN and JINR, Dubna, and carried out at the TATRA truck plant at Koprivinice, Czech Republic. It was a great success. Approximately 41,000 plates were stamped and fully met specification. Moreover, the production time was significantly reduced by avoiding the need of ...
Date: March 10, 1999
Creator: Guarino, V.J.; Hill, N.; Petereit, E.; Price, L.E.; Proudfoot, J. & Wood, K.
Partner: UNT Libraries Government Documents Department

Simplified analytic formula for magneto-optical Kerr effects in ultrathin magnetic films.

Description: Expressions are presented for various magneto-optical Kerr effects in the ultrathin film limit with arbitrary magnetization direction by considering the multiple reflections within an optically thin film. The Kerr effect of p- and s-polarization consists of products of two factors: the prefactor, dependent only on the optical parameters of the system, and the main factor of the polar Kerr effect for normal incidence in the ultrathin limit.
Date: June 10, 1998
Creator: You, C.-Y.
Partner: UNT Libraries Government Documents Department

Confinement of Pure Ion Plasma in a Cylindrical Current Sheet

Description: A novel method for containing a pure ion plasma at thermonuclear densities and temperatures has been modeled. The method combines the confinement properties of a Penning-Malmberg trap and some aspects of the magnetic field geometry of a pulsed theta-pinch. A conventional Penning trap can confine a uniform-density plasma of about 5x1011 cm-3 with a 30-Tesla magnetic field. However, if the axial field is ramped, a much higher local ion density can be obtained. Starting with a 107 cm-3 trapped deuterium plasma in a conventional Penning-Malmberg trap at the Brillouin limit (B = 0.6 Tesla), the field is ramped to 30 Tesla. Because the plasma is comprised of particles of only one sign of charge, transport losses are very low, i.e., the conductivity is high. As a result, the ramped field does not penetrate the plasma and a diamagnetic surface current is generated, with the ions being accelerated to relativistic velocities. To counteract the inward j x B forces from this induced current, additional ions are injected into the plasma along the axis to increase the density (and mutual electrostatic repulsion) of the target plasma. In the absence of the higher magnetic field in the center, the injected ions drift outward until a balance is established between the outward driving forces (centrifugal, electrostatic, pressure gradient) and the inward j x B force. An equilibrium calculation using a relativistic, 1-D, cold-fluid model shows that a plasma can be trapped in a hollow, 49-cm diameter, 0.2-cm thick cylinder with a density exceeding 4 x 1014 cm-3.
Date: December 10, 1999
Creator: Phillips, C.K.; Chao, E.H.; Davidson, R.C. & Paul, S.F.
Partner: UNT Libraries Government Documents Department

Improved Efficiency of Miscible C02 Floods and Enhanced Prospects for C02 Flooding Heterogeneous Reservoirs

Description: Surfactant and foam properties have been evaluated at high pressure using the foam durability apparatus. For a number of surfactant solutions the interfacial tension with cense CO2, critical micelle concentrations, foaming ability, and foam stability were determined. Preliminary results show that these tests correlate well to predict surfactant properties and mobility in cores. Work has also restarted in the parallel-dual permeability system.
Date: October 10, 1996
Creator: Guo, Boyn (Gordon); Schechter, David S.; Tsau, Jyun-Syung; Grigg, Reid B. & Chang, Shih-Hsien (Eric)
Partner: UNT Libraries Government Documents Department

European organization for nuclear research

Description: The CERN Intersecting Storage Rings (ISR) operated from 1971 to 1984. During that time high-energy physics experiments were carried out with 30 GeV colliding proton beams. At the end of this period the machine was decommissioned and dismantled. This involved the movement of about 1000 machine elements, e.g., magnets, vacuum pumps, rf cavities, etc., 2500 racks, 7000 shielding blocks, 3500 km of cables and 7 km of beam piping. All these items were considered to be radioactive until the contrary was proven. They were then sorted, either for storage and reuse or for radioactive or non-radioactive waste. The paper describes the radiation protection surveillance of this project which lasted for five months. It includes the radiation protection standards, the control of personnel and materials, typical radioactivity levels and isotopes, as well as final cleaning and decommissioning of an originally restricted radiation area to a free accessible area.
Date: September 10, 1987
Creator: Schoenbacher, H. & Tavlet, M.
Partner: UNT Libraries Government Documents Department

Experiments on explosive interactions between zirconium-containing melt and water (ZREX).

Description: The results of two series of experiments on explosive interactions between zirconium-containing melt and water are described. The first series of experiments involved dropping 1-kg batches of zirconium-zirconium dioxide mixture melt into a column of water while the second series employed 1.2-kg batches of zirconium-stainless steel mixture melt. Explosions took place only in those tests which were externally triggered. While the extent of zirconium oxidation in the triggered experiments was quite large, the explosion energies estimated from the experimental measurements were found to be small compared to the combined thermal and chemical energy available.
Date: April 10, 1998
Creator: Cho, D. H.
Partner: UNT Libraries Government Documents Department

Fundamental studies of the plasma extraction and ion beam formation processes in inductively coupled plasma mass spectrometry

Description: The fundamental and practical aspects are described for extracting ions from atmospheric pressure plasma sources into an analytical mass spectrometer. Methodologies and basic concepts of inductively coupled plasma mass spectrometry (ICP-MS) are emphasized in the discussion, including ion source, sampling interface, supersonic expansion, slumming process, ion optics and beam focusing, and vacuum considerations. Some new developments and innovative designs are introduced. The plasma extraction process in ICP-MS was investigated by Langmuir measurements in the region between the skimmer and first ion lens. Electron temperature (T{sub e}) is in the range 2000--11000 K and changes with probe position inside an aerosol gas flow. Electron density (n{sub e}) is in the range 10{sup 8}--10{sup 10} {sup {minus}cm }at the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} near the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} downstream further behind the skimmer. Electron density in the beam leaving the skimmer also depends on water loading and on the presence and mass of matrix elements. Axially resolved distributions of electron number-density and electron temperature were obtained to characterize the ion beam at a variety of plasma operating conditions. The electron density dropped by a factor of 101 along the centerline between the sampler and skimmer cones in the first stage and continued to drop by factors of 10{sup 4}--10{sup 5} downstream of skimmer to the entrance of ion lens. The electron density in the beam expansion behind sampler cone exhibited a 1/z{sup 2} intensity fall-off (z is the axial position). An second beam expansion originated from the skimmer entrance, and the beam flow underwent with another 1/z{sup 2} fall-off behind the skimmer. Skimmer interactions play an important role in plasma extraction in the ICP-MS instrument.
Date: February 10, 1995
Creator: Niu, Hongsen
Partner: UNT Libraries Government Documents Department

Novel catalysts for methane activation. Quarterly report number 10, January 1--March 31, 1995

Description: Fullerenes are a recently discovered allotrope of carbon that possess unusual properties, some of which may be ideal for methane activation. This project is designed to evaluate these carbon-based materials for conversion of methane into higher hydrocarbons. The project is divided into three technical tasks: synthesis and characterization of the fullerenes and fullerene soots; testing of catalysts; and evaluation of the results and technical reporting. The authors had two objectives for this quarter. The first objective was to complete their study of the K-doped fullerene soots to include the selectivity of these materials as a function of methane conversion. The second objective was to identify and evaluate other metal promoters, and the combination of transition and alkali metals to enhance the selectivity of the methane conversion process and hopefully reduce the temperature of reaction. Results from these two tasks are discussed.
Date: June 10, 1995
Creator: Hirschon, A.S.; Du, Y.; Wu, H.J.; Malhotra, R. & Wilson, R.B.
Partner: UNT Libraries Government Documents Department

Magnetosonic Eigenmodes Near the Magnetic Field Well in a Spherical Torus

Description: The structure and spectrum of magnetosonic Alfven eigenmodes in spherical torus in the presence of magnetic field well are studied. Analytical solution for eigenmodes localized in the well is obtained and compared with the numerical one. The possibility of using the eigenmode spectrum measurements for reconstructing the magnetic field well, and, thus, central magnetic safety factor profile is discussed.
Date: July 10, 1998
Creator: Gorelenkova, M. V. & Gorelenkov, N. N.
Partner: UNT Libraries Government Documents Department

Corrosion of candidate container materials by Yucca Mountain bacteria

Description: Several candidate container materials have been studied in modified Yucca Mountain (YM) ground water in the presence or absence of YM bacteria. YM bacteria increased corrosion rates by 5-6 fold in UNS G10200 carbon steel, and nearly 100-fold in UNS NO4400 Ni-Cu alloy. YM bacteria caused microbiologically influenced corrosion (MIC) through de-alloying or Ni-depletion of Ni-Cu alloy as evidenced by scanning electronic microscopy (SEM) and inductively coupled plasma spectroscopy (ICP) analysis. MIC rates of more corrosion-resistant alloys such as UNS NO6022 Ni-Cr- MO-W alloy, UN's NO6625 Ni-Cr-Mo alloy, and UNS S30400 stainless steel were measured below 0.05 umyr, however YM bacteria affected depletion of Cr and Fe relative to Ni in these materials. The chemical change on the metal surface caused by depletion was characterized in anodic polarization behavior. The anodic polarization behavior of depleted Ni-based alloys was similar to that of pure Ni. Key words: MIC, container materials, YM bacteria, de-alloying, Ni-depletion, Cr-depletion, polarization resistance, anodic polarization,
Date: December 10, 1999
Creator: Horn, J; Jones, D; Lian, T; Martin, S & Rivera, A
Partner: UNT Libraries Government Documents Department

Acoustic waves in random ensembles of magnetic fluxes

Description: To analyze the observational data and provide the appropriate diagnostic procedure for photospheric manifestation of solar oscillations it is necessary to take into account strong inhomogeneity of solar atmosphere with respect to distribution of magnetic fields. We study the collective phenomena in the propagation of acoustic waves and unsteady wave-packets through quite regions, sunspots and plages, including time-dependent response of these regions to solar oscillations, the energy transfer mechanisms, frequency shift effects and reradiation of the acoustic waves in higher layers of atmosphere. We show that the dynamics of differently magnetized regions, their dispersion properties, and their response to the propagation of acoustic waves are completely different. We describe the effects caused by the specific distribution and randomness of magnetic flux tubes, which can be observed and which can provide the tools for diagnostic goals.
Date: October 10, 1995
Creator: Ryutova, M.P.
Partner: UNT Libraries Government Documents Department

Quarterly Technical Progress Report - Investigation of Syngas Interaction in Alcohol Synthesis Catalysts

Description: This report presents the work done on " Investigation of Syngas Interaction in Alcohol Synthesis Catalysts" during the last quarter. The major activity during this period is on FTIR absorption studies of Co/Cr catalysts using CO as a probe molecule. Transition metals cobalt and copper play significant roles in the conversion of syngas (CO + H2 ) to liquid fuels. With a view to examine the nature of interaction between CO and metal, the FTIR spectra of CO adsorbed on Co-Cr2 O3 composites were investigated. The results indicate that as cobalt loading increases, the intensity of the CO adsorption bands increase and several vibrational modes seem to be promoted. Heat treatment of the sample revealed two distinct processes of adsorption. Bands due to physisorption disappeared while bands due to chemisorption not only increased in intensity but persisted even after desorption. It seems that the physisorption process is more active when the catalyst is fresh and is hindered when carbidic/carbonyl formations occur on the metal surfaces.
Date: November 10, 1998
Creator: Akundi, Murty A.
Partner: UNT Libraries Government Documents Department

Adaptive, multiresolution visualization of large data sets using parallel octrees.

Description: The interactive visualization and exploration of large scientific data sets is a challenging and difficult task; their size often far exceeds the performance and memory capacity of even the most powerful graphics work-stations. To address this problem, we have created a technique that combines hierarchical data reduction methods with parallel computing to allow interactive exploration of large data sets while retaining full-resolution capability. The hierarchical representation is built in parallel by strategically inserting field data into an octree data structure. We provide functionality that allows the user to interactively adapt the resolution of the reduced data sets so that resolution is increased in regions of interest without sacrificing local graphics performance. We describe the creation of the reduced data sets using a parallel octree, the software architecture of the system, and the performance of this system on the data from a Rayleigh-Taylor instability simulation.
Date: June 10, 1999
Creator: Freitag, L. A. & Loy, R. M.
Partner: UNT Libraries Government Documents Department

POC-SCALE TESTING OF A DRY TRIBOELECTROSTATIC SEPARATOR FOR FINE COAL CLEANING

Description: It is the objective of the project to further develop the triboelectrostatic separation (TES) process developed at the Federal Energy Technology Center (FETC) and to test the process at a proof-of-concept (POC) scale. This process has a distinct advantage over other coal cleaning processes in that it does not entail costly steps of dewatering. The POC-scale unit is to be developed based on (i) the charging characteristics of coal and mineral matter that can be determined using the novel on-line tribocharge measuring device developed at Virginia Tech and (ii) the results obtained from bench-scale TES tests conducted on three different coals. During the past quarter, most of the personnel assigned to this project have been performing work elements associated with the engineering design (Task 3) of the TES process. This activity has been subdivided into three subtasks, i.e., Charger Tests (Subtask 3.1), Separator Tests (Subtask 3.2), and Final POC Design (Subtask 3.3). In Subtask 3.1, several different tribocharging devices have been constructed using materials of various work functions. They are currently being tested to establish the best materials to be used for designing and manufacturing the optimum tribochargers that can maximum charge differences between coal and mineral matter. In Subtask 3.2, bench-scale cleaning tests have been conducted to study the effects of the various operating and design parameters on the performance of the electrostatic separator. Two different TES units have been tested to date. One uses drum-type electrodes to separate charged particles, while the other uses plate-type electrodes for the separation. The test results showed that a major improvement in separation efficiency can be achieved by recycling the middlings back to the feed stream. It has also been established that the major source of inefficiency arises from the difficulty in separating ultrafine particles. Understanding the behavior of the ultrafine particles ...
Date: March 10, 1999
Creator: Yan, E.S.; Luttrell, G.H.; Adel, G.T. & Yoon, R.-H.
Partner: UNT Libraries Government Documents Department

Hard Parton Physics in High Energy Nuclear Collisions. Proceedings of RIKEN BNL Research Center Workshop, Volume 17

Description: The RIKEN-BNL center workshop on ''Hard parton physics in high energy nuclear collisions'' was held at BNL from March 1st-5th! 1999. The focus of the workshop was on hard probes of nucleus-nucleus collisions that will be measured at RHIC with the PHENIX and STAR detectors. There were about 45 speakers and over 70 registered participants at the workshop, with roughly a quarter of the speakers from overseas. About 60% of the talks were theory talks. A nice overview of theory for RHIC was provided by George Sterman. The theoretical talks were on a wide range of topics in QCD which can be classified under the following: (a) energy loss and the Landau-Pomeranchuk-Migdal effect; (b) minijet production and equilibration; (c) small x physics and initial conditions; (d) nuclear parton distributions and shadowing; (e) spin physics; (f) photon, di-lepton, and charm production; and (g) hadronization, and simulations of high pt physics in event generators. Several of the experimental talks discussed the capabilities of the PHENIX and STAR detectors at RHIC in measuring high pt particles in heavy ion collisions. In general, these talks were included in the relevant theory sessions. A session was set aside to discuss the spin program at RHIC with polarized proton beams. In addition, there were speakers from 08, HERA, the fixed target experiments at Fermilab, and the CERN fixed target Pb+Pb program, who provided additional perspective on a range of issues of relevance to RHIC; from jets at the Tevatron, to saturation of parton distributions at HERA, and recent puzzling data on direct photon production in fixed target experiments, among others.
Date: September 10, 1999
Creator: Carroll, J.
Partner: UNT Libraries Government Documents Department

Condensation induced water hammer safety

Description: Condensation induced water hammer events in piping systems can cause catastrophic steam system failures which can result in equipment damage, personal injury, and even death. As an industry, we have learned to become accustomed to the ''banging'' that we often hear in our steam piping systems, and complacent in our actions to prevent it. It is unfortunate that lives are lost needlessly, as this type of water hammer event is preventable if one only applies some basic principles when operating and maintaining their steam systems. At the U. S. Department of Energy's Hanford Site where I work, there was one such accident that occurred in 1993 which took the life of a former co-worker and friend of mine. Hanford was established as part of the Manhattan Project during World War II. it is a 560 square mile complex located along the banks of the Columbia River in Southeastern Washington State. For almost 45 years, hanford's mission was to produce weapons grade plutonium for our nations defense programs. Today, Hanford no longer produces plutonium, but is focused on site clean-up and economic diversification. Hanford still uses steam for heating and processing activities, utilizing over 20 miles of piping distribution systems similar to those found in industry. Although these aging systems are still sound, they cannot stand up to the extreme pressure pulses developed by a condensation induced water hammer.
Date: March 10, 1997
Creator: Gintner, M.A.
Partner: UNT Libraries Government Documents Department

Design of a gate-turn-off (GTO) switch for pulsed power application.

Description: A Gate-Turn-Off (GTO) thyristor switch and its gate drive circuit have been developed as a replacement for the thyratron switch used in the positron converter solenoid lens power supply at the Advanced Photon Source (APS) to deliver a current pulse of 6000 A at 60-Hz repetition rate. This paper discusses the characteristics of the GTOs under consideration, the gate drive circuit, and some test results.
Date: July 10, 1998
Creator: Despe, O.
Partner: UNT Libraries Government Documents Department

Performance and lifetime assessment of reactor wall and nearby components during plasma instabilities.

Description: Surface and structural damage to plasma-facing components due to the frequent loss of plasma confinement is a serious problem for the tokamak reactor concept. The plasma energy deposited on these components during loss of confinement causes significant surface erosion, possible structural failure, and frequent plasma contamination. Surface damage consists of vaporization, spallation, and liquid splatter of metallic materials. Comprehensive multidimensional models that include thermodynamics and thermal hydraulics of plasma-facing materials, eroded-debris/vapor atomic physics and magnetohydrodynamics, resulting photon radiation and photon transport, as well as liquid splashing and brittle destruction of materials, are used self-consistently to evaluate and assess our current understanding of the lifetime of plasma-facing materials and the various forms of damage they experience. Models are developed to study the stability of the vapor shielding layer, erosion of the melt-layer, brittle destruction/explosive erosion, and the issues involved therein.
Date: March 10, 1998
Creator: Hassanein, A.
Partner: UNT Libraries Government Documents Department

Large scale demonstration project at Argonne National Laboratory's CP-5 reactor.

Description: The world's largest environmental cleanup effort continues to be focused on the Department of Energy (DOE) complex. The significant technical and economic concerns associated with this effort underscore the need for crucial cost-effective technologies and management approaches.
Date: June 10, 1998
Creator: Wiese, E. C.
Partner: UNT Libraries Government Documents Department

RARE KAON DECAYS.

Description: The past few years have seen an evolution in the study of rare K decays from a concentration on explicitly Standard Model (SM) violating decays such as K{sub L}{sup 0} {r_arrow} {mu}e, to one on SM-allowed but suppressed decays such as K {r_arrow} {pi}{nu}{bar {nu}}, in which short-distance interactions are dominant. There are also a number of recent experimental and theoretical studies of long-distance-dominated decays, but they do not have space to cover these, with the exception of those that are needed in the discussion of the short-distance-dominated processes.
Date: June 10, 1999
Creator: KUDENKO,Y.
Partner: UNT Libraries Government Documents Department

Parameter analysis for a high-gain harmonic generation FEL using a recently developed 3D polychromatic code.

Description: One possible design for a fourth-generation light source is the high-gain harmonic generation (HGHG) free-electron laser (FEL). Here, a coherent seed with a wavelength at a subharmonic of the desired output radiation interacts with the electron beam in an energy-modulating section. This energy modulation is then converted into spatial bunching while traversing a dispersive section (a three-dipole chicane). The final step is passage through a radiative section, an undulator tuned to the desired higher harmonic output wavelength. The coherent seed serves to remove noise and can be at a much lower subharmonic of the output radiation, thus eliminating the concerns found in self-amplified spontaneous emission (SASE) and seeded FELs, respectively. Recently, a 3D code that includes multiple frequencies, multiple undulatory (both in quantity and/or type), quadruple magnets, and dipole magnets was developed to easily simulate HGHG. Here, a brief review of the HGHG theory, the code development, the Accelerator Test Facility's (ATF) HGHG FEL experimental parameters, and the parameter analysis from simulations of this specific experiment will be discussed.
Date: September 10, 1999
Creator: Biedron, S. G.; Freund, H. P. & Yu, L.-H.
Partner: UNT Libraries Government Documents Department