Sample records for axial magma chamber

  1. Volcano-tectonic modelling of magma chambers, ring-faults, unrest, and eruptions in the Tianchi Volcano, China

    E-Print Network [OSTI]

    Sheldon, Nathan D.

    this range to AD938-946), produced between 96 and 172 km3 of deposits, or around 30 km3 of dense magma, and is one of the largest eruptions on Earth during the past 1100 years. A 5-km-diameter collapse caldera, indicating that the shallow magma chamber and/or an associated geothermal system beneath the volcano

  2. The earliest history of the Skaergaard magma chamber: a textural and geochemical study of the Cambridge Drill Core

    E-Print Network [OSTI]

    Holness, Marian B.; Tegner, Christian; Namur, Olivier; Pilbeam, Llewellyn

    2015-01-01T23:59:59.000Z

    Pilbeam, Llewellyn; University of Cambridge, Dept of Earth Sciences Keyword: Skaergaard, magma chamber, intrusion, cumulate, gabbro, geochemistry, layered igneous rock, mineral chemistry http://www.petrology.oupjournals.org/ Manuscript submitted... and olivines (Nwe, 1975; 1976), plagioclase (Maaløe, 1976; Humphreys, 2009; Namur et al., 2014), rhythmic layering (Maaløe, 1978; 1987) and uranium content (Henderson, 1975). Maaløe’s detailed 1976 study of plagioclase in the drill core outlines the cryptic...

  3. Investigation of MAGMA chambers in the Western Great Basin. Final report, 9 June 1982-31 October 1985

    SciTech Connect (OSTI)

    Peppin, W.A.

    1986-02-10T23:59:59.000Z

    This report summarizes efforts made by the Seismological Laboratory toward the detection and delineation of shallow crustal zones in the western Great Basin, and toward the development of methods to accomplish such detection. The work centers around the recently-active volcanic center near Long Valley, California. The work effort is broken down into three tasks: (1) network operations, (2) data analysis and interpretation, and (3) the study of shallow crustal amomalies (magma bodies). Section (1) describes the efforts made to record thousand of earthquakes near the Long Valley caldera, and focusses on the results obtained for the November 1984 round Valley earthquake. Section (2) describes the major effort of this contract, which was to quantify the large volume of seismic data being recorded as it pertains to the goals of this contract. Efforts described herein include (1) analysis of earthquake focal mechanisms, and (2) the classification, categorization, and interpretation of unusual seismic phases in terms of reflections and refractions from shallow-crustal anomalous zones. Section (3) summarizes the status of our research to date on the locations of magma bodies, with particular emphasis on a location corresponding to the map location of the south end of Hilton Creek fault. Five lines of independent evidence suggest that magma might be associated with this spot. Finally, new evidence on the large magma bodies within the Long Valley caldera, of interest to the DOE deep drilling project, is presented.

  4. High-voltage crowbar protection for the large CDF axial drift chamber

    SciTech Connect (OSTI)

    Binkley, M.; Mukherjee, A.; Stuermer, W.; Wagner, R.L.; /Fermilab

    2004-01-01T23:59:59.000Z

    The Central Outer Tracker (COT) is a big cylindrical drift chamber that provides charged particle tracking for the Collider Detector at Fermilab experiment. To protect the COT, the large stored energy in the high voltage system needs to be removed quickly when a problem is sensed. For the high voltage switch, a special-order silicon-controlled-rectifier was chosen over more readily available integrated gate bipolar transistors because of layout and reliability questions. The considerations concerning the high voltage switch, the prototype performance, and the experience of more than two years of running are described.

  5. Magma energy

    SciTech Connect (OSTI)

    Dunn, J.C.

    1987-01-01T23:59:59.000Z

    The thermal energy contained in magmatic systems represents a huge potential resource. In the US, useful energy contained in molten and partially-molten magma within the upper 10 km of the crust has been estimated at 5 to 50 x 10/sup 22/ J (50,000 to 500,000 Quads). The objective of the Magma Energy Extraction Program is to determine the engineering feasibility of locating, accessing, and utilizing magma as a viable energy resource. This program follows the DOE/OBES-funded Magma Energy Research Project that concluded scientific feasibility of the magma energy concept. A primary long-range goal of this program is to conduct an energy extraction experiment directly in a molten, crustal magma body. Critical to determining engineering feasibility are several key technology tasks: (1) Geophysics - to obtain detailed definition of potential magma targets, (2) Geochemistry/Materials - to characterize the magma environment and select compatible engineering materials, (3) Drilling - to develop drilling and completion techniques for entry into a magma body, and (4) Energy Extraction - to develop heat extraction technology.

  6. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor (Manassas, VA)

    2011-01-18T23:59:59.000Z

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  7. Magma energy: a feasible alternative

    SciTech Connect (OSTI)

    Colp, J.L.

    1980-03-01T23:59:59.000Z

    A short review of the work performed by Sandia Laboratories in connection with its Magma Energy Research Project is provided. Results to date suggest that boreholes will remain stable down to magma depths and engineering materials can survive the downhole environments. Energy extraction rates are encouraging. Geophysical sensing systems and interpretation methods require improvement, however, to clearly define a buried magma source.

  8. Magma energy: engineering feasibility of energy extraction from magma bodies

    SciTech Connect (OSTI)

    Traeger, R.K.

    1983-12-01T23:59:59.000Z

    A research program was carried out from 1975 to 1982 to evaluate the scientific feasibility of extracting energy from magma, i.e., to determine if there were any fundamental scientific roadblocks to tapping molten magma bodies at depth. The next stage of the program is to evaluate the engineering feasibility of extracting energy from magma bodies and to provide insight into system economics. This report summarizes the plans, schedules and estimated costs for the engineering feasibility study. Tentative tasks and schedules are presented for discussion and critique. A bibliography of past publications on magma energy is appended for further reference. 69 references.

  9. Co-axial, high energy gamma generator

    DOE Patents [OSTI]

    Reijonen, Jani Petteri (Princeton, NJ); Gicquel, Frederic (Pennington, NJ)

    2011-08-16T23:59:59.000Z

    A gamma ray generator includes an ion source in a first chamber. A second chamber is configured co-axially around the first chamber at a lower second pressure. Co-axially arranged plasma apertures separate the two chambers and provide for restricted passage of ions and gas from the first to the second chamber. The second chamber is formed by a puller electrode having at least one long channel aperture to draw ions from the first chamber when the puller electrode is subject to an appropriate applied potential. A plurality of electrodes rings in the third chamber in third pressure co-axially surround the puller electrode and have at least one channel corresponding to the at least one puller electrode aperture and plasma aperture. The electrode rings increase the energy of the ions to a selected energy in stages in passing between successive pairs of the electrodes by application of an accelerating voltage to the successive pairs of accelerator electrodes. A target disposed co-axially around the plurality of electrodes receives the beam of accelerated ions, producing gamma rays.

  10. Cyclone reactor with internal separation and axial recirculation

    DOE Patents [OSTI]

    Becker, Frederick E. (Reading, MA); Smolensky, Leo A. (Concord, MA)

    1989-01-01T23:59:59.000Z

    A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combuston chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture of flue gas and ash may be tangentially withdrawn from the outlet end of the combustor chamber and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture.

  11. Cyclone reactor with internal separation and axial recirculation

    DOE Patents [OSTI]

    Becker, F.E.; Smolensky, L.A.

    1988-07-19T23:59:59.000Z

    A cyclone combustor apparatus contains a circular partition plate containing a central circular aperture is described. The partition plate divides the apparatus into a cylindrical precombustor chamber and a combustor chamber. A coal-water slurry is passed axially into the inlet end of the precombustor chamber, and primary air is passed tangentially into said chamber to establish a cyclonic air flow. Combustion products pass through the partition plate aperture and into the combustor chamber. Secondary air may also be passed tangentially into the combustor chamber adjacent the partition plate to maintain the cyclonic flow. Flue gas is passed axially out of the combustor chamber at the outlet end and ash is withdrawn tangentially from the combustor chamber at the outlet end. A first mixture of flue gas and ash may be tangentially withdrawn from the combustor chamber at the outlet end and recirculated to the axial inlet of the precombustor chamber with the coal-water slurry. A second mixture may be tangentially withdrawn from the outlet end and passed to a heat exchanger for cooling. Cooled second mixture is then recirculated to the axial inlet of the precombustor chamber. In another embodiment a single cyclone combustor chamber is provided with both the recirculation streams of the first mixture and the second mixture. 10 figs.

  12. Exposure chamber

    DOE Patents [OSTI]

    Moss, Owen R. (Kennewick, WA)

    1980-01-01T23:59:59.000Z

    A chamber for exposing animals, plants, or materials to air containing gases or aerosols is so constructed that catch pans for animal excrement, for example, serve to aid the uniform distribution of air throughout the chamber instead of constituting obstacles as has been the case in prior animal exposure chambers. The chamber comprises the usual imperforate top, bottom and side walls. Within the chamber, cages and their associated pans are arranged in two columns. The pans are spaced horizontally from the walls of the chamber in all directions. Corresponding pans of the two columns are also spaced horizontally from each other. Preferably the pans of one column are also spaced vertically from corresponding pans of the other column. Air is introduced into the top of the chamber and withdrawn from the bottom. The general flow of air is therefore vertical. The effect of the horizontal pans is based on the fact that a gas flowing past the edge of a flat plate that is perpendicular to the flow forms a wave on the upstream side of the plate. Air flows downwardly between the chamber walls and the outer edges of the pan. It also flows downwardly between the inner edges of the pans of the two columns. It has been found that when the air carries aerosol particles, these particles are substantially uniformly distributed throughout the chamber.

  13. Ionization chamber

    DOE Patents [OSTI]

    Walenta, Albert H. (Port Jefferson Station, NY)

    1981-01-01T23:59:59.000Z

    An ionization chamber has separate drift and detection regions electrically isolated from each other by a fine wire grid. A relatively weak electric field can be maintained in the drift region when the grid and another electrode in the chamber are connected to a high voltage source. A much stronger electric field can be provided in the detection region by connecting wire electrodes therein to another high voltage source. The detection region can thus be operated in a proportional mode when a suitable gas is contained in the chamber. High resolution output pulse waveforms are provided across a resistor connected to the detection region anode, after ionizing radiation enters the drift region and ionize the gas.

  14. Performance of An Axial Gas Ionization Detector

    E-Print Network [OSTI]

    S. Adhikari; C. Basu; C. Samanta; S. S. Brahmachari; B. P. Das; P. Basu

    2006-10-11T23:59:59.000Z

    An axial gas ionization chamber has been fabricated for use as a $\\Delta E$ detector in heavy ion induced nuclear reactions. Different operating parameters such as gas type, pressure, anode voltage and anode structures have been optimized. The transparency of the anode structure is observed to play an important role in improving the energy resolution of the detector.

  15. Target Chamber

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposedPAGESafety Tag:8, 2013 FINALTarget Chamber The

  16. Chamber transport

    SciTech Connect (OSTI)

    OLSON,CRAIG L.

    2000-05-17T23:59:59.000Z

    Heavy ion beam transport through the containment chamber plays a crucial role in all heavy ion fusion (HIF) scenarios. Here, several parameters are used to characterize the operating space for HIF beams; transport modes are assessed in relation to evolving target/accelerator requirements; results of recent relevant experiments and simulations of HIF transport are summarized; and relevant instabilities are reviewed. All transport options still exist, including (1) vacuum ballistic transport, (2) neutralized ballistic transport, and (3) channel-like transport. Presently, the European HIF program favors vacuum ballistic transport, while the US HIF program favors neutralized ballistic transport with channel-like transport as an alternate approach. Further transport research is needed to clearly guide selection of the most attractive, integrated HIF system.

  17. Ground surface deformation patterns, magma supply, and magma storage at Okmok volcano, Alaska, from InSAR analysis

    E-Print Network [OSTI]

    Biggs, Juliet

    Click Here for Full Article Ground surface deformation patterns, magma supply, and magma storage., and S. McNutt (2010), Ground surface deformation patterns, magma supply, and magma storage at Okmok at Okmok volcano and continuing until the start of the 2008 eruption, magma accumulated in a storage zone

  18. Magma energy and geothermal permeability enhancement programs

    SciTech Connect (OSTI)

    Dunn, J.C.

    1985-01-01T23:59:59.000Z

    Accomplishments during FY85 and project plans for FY86 are described for the Magma Energy Extraction and Permeability Enhancement programs. (ACR)

  19. Magma Energy Research Project, FY80 annual progress report

    SciTech Connect (OSTI)

    Colp, J.L. (ed.)

    1982-04-01T23:59:59.000Z

    The technical feasibility of extracting energy from magma bodies is explored. Five aspects of the project are studied: resource location and definition, source tapping, magma characterization, magma/material compatibility, and energy extraction.

  20. Causes and consequences of unsteady crustal magma transport

    E-Print Network [OSTI]

    Karlstrom, Leif

    2011-01-01T23:59:59.000Z

    Cooling and crystallization in sheet-like magma bodies revisited. Journal of Vol- canology and Geothermal

  1. Final report - Magma Energy Research Project

    SciTech Connect (OSTI)

    Colp, J.L.

    1982-10-01T23:59:59.000Z

    Scientific feasibility was demonstrated for the concept of magma energy extraction. The US magma resource is estimated at 50,000 to 500,000 quads of energy - a 700- to 7000-yr supply at the current US total energy use rate of 75 quads per year. Existing geophysical exploration systems are believed capable of locating and defining magma bodies and were demonstrated over a known shallow buried molten-rock body. Drilling rigs that can drill to the depths required to tap magma are currently available and experimental boreholes were drilled well into buried molten rock at temperatures up to 1100/sup 0/C. Engineering materials compatible with the buried magma environment are available and their performances were demonstrated in analog laboratory experiments. Studies show that energy can be extracted at attractive rates from magma resources in all petrologic compositions and physical configurations. Downhole heat extraction equipment was designed, built, and demonstrated successfully in buried molten rock and in the very hot margins surrounding it. Two methods of generating gaseous fuels in the high-temperature magmatic environment - generation of H/sub 2/ by the interaction of water with the ferrous iron and H/sub 2/, CH/sub 4/, and CO generation by the conversion of water-biomass mixtures - have been investigated and show promise.

  2. Measuring axial pump thrust

    DOE Patents [OSTI]

    Suchoza, B.P.; Becse, I.

    1988-11-08T23:59:59.000Z

    An apparatus for measuring the hydraulic axial thrust of a pump under operation conditions is disclosed. The axial thrust is determined by forcing the rotating impeller off of an associated thrust bearing by use of an elongate rod extending coaxially with the pump shaft. The elongate rod contacts an impeller retainer bolt where a bearing is provided. Suitable measuring devices measure when the rod moves to force the impeller off of the associated thrust bearing and the axial force exerted on the rod at that time. The elongate rod is preferably provided in a housing with a heat dissipation mechanism whereby the hot fluid does not affect the measuring devices. 1 fig.

  3. Measuring axial pump thrust

    DOE Patents [OSTI]

    Suchoza, Bernard P. (McMurray, PA); Becse, Imre (Washington, PA)

    1988-01-01T23:59:59.000Z

    An apparatus for measuring the hydraulic axial thrust of a pump under operation conditions is disclosed. The axial thrust is determined by forcing the rotating impeller off of an associated thrust bearing by use of an elongate rod extending coaxially with the pump shaft. The elongate rod contacts an impeller retainer bolt where a bearing is provided. Suitable measuring devices measure when the rod moves to force the impeller off of the associated thrust bearing and the axial force exerted on the rod at that time. The elongate rod is preferably provided in a housing with a heat dissipation mechanism whereby the hot fluid does not affect the measuring devices.

  4. Axial static mixer

    DOE Patents [OSTI]

    Sandrock, H.E.

    1982-05-06T23:59:59.000Z

    Static axial mixing apparatus includes a plurality of channels, forming flow paths of different dimensions. The axial mixer includes a flow adjusting device for adjustable selective control of flow resistance of various flow paths in order to provide substantially identical flows through the various channels, thereby reducing nonuniform coating of interior surfaces of the channels. The flow adjusting device may include diaphragm valves, and may further include a pressure regulating system therefor.

  5. ORIGINAL PAPER Granite magma migration and emplacement along thrusts

    E-Print Network [OSTI]

    Galland, Olivier

    ORIGINAL PAPER Granite magma migration and emplacement along thrusts Eric C. Ferre´ · Olivier in the emplacement of granite plutons in contractional settings. We address both cases where contractional tectonics. This phenomenon occurs for both low-viscosity magma (basalts to andesite) and high-viscosity magma (dry granite

  6. RESEARCH ARTICLE Caldera resurgence during magma replenishment

    E-Print Network [OSTI]

    City calderas Ben Kennedy & Jack Wilcock & John Stix Received: 16 February 2012 /Accepted: 30 June 2012 of thousands of years or less). (2) Immedi- ately before and during resurgence, dacite magma was intruded and developed faults and fractures. This fluid movement allows hydrothermal and geothermal systems to form

  7. BNL | ATF Experimental Chambers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laser Injection Vacuum Chamber Located on beam line 1, the "Smith-Purcell box" has 140 liters of usable volume. Due to its size, it is mounted on a fixed platform. Hosted...

  8. BNL | ATF Interaction Chambers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    chamber can be used for more than just plasma wakefield experiments. Dedicated 500 ls turbo pump and one auxiliary 200 ls turbo pump port. Normally operates in the 10-8 Torr...

  9. BNL | ATF Interaction Chambers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    with translation actuators. Beam profile monitors at interaction region as well as chamber entrance and exit. Available port for 200 ls turbo pump. Operates in the 10-8 Torr range...

  10. BNL | ATF Experimental Chambers

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    entrance and exit. Dedicated ion pumps (250 ls total) with a port for one 200 ls turbo pump. Operates in the 10-8 Torr range. Photo of open DWFA chamber, in-situ on beam...

  11. Sleeve reaction chamber system

    DOE Patents [OSTI]

    Northrup, M. Allen (Berkeley, CA); Beeman, Barton V. (San Mateo, CA); Benett, William J. (Livermore, CA); Hadley, Dean R. (Manteca, CA); Landre, Phoebe (Livermore, CA); Lehew, Stacy L. (Livermore, CA); Krulevitch, Peter A. (Pleasanton, CA)

    2009-08-25T23:59:59.000Z

    A chemical reaction chamber system that combines devices such as doped polysilicon for heating, bulk silicon for convective cooling, and thermoelectric (TE) coolers to augment the heating and cooling rates of the reaction chamber or chambers. In addition the system includes non-silicon-based reaction chambers such as any high thermal conductivity material used in combination with a thermoelectric cooling mechanism (i.e., Peltier device). The heat contained in the thermally conductive part of the system can be used/reused to heat the device, thereby conserving energy and expediting the heating/cooling rates. The system combines a micromachined silicon reaction chamber, for example, with an additional module/device for augmented heating/cooling using the Peltier effect. This additional module is particularly useful in extreme environments (very hot or extremely cold) where augmented heating/cooling would be useful to speed up the thermal cycling rates. The chemical reaction chamber system has various applications for synthesis or processing of organic, inorganic, or biochemical reactions, including the polymerase chain reaction (PCR) and/or other DNA reactions, such as the ligase chain reaction.

  12. The Magma Energy Program | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f <MaintainedInformation 2EnergyCityGreen Data Book JumpMagma

  13. Automated soil gas monitoring chamber

    DOE Patents [OSTI]

    Edwards, Nelson T.; Riggs, Jeffery S.

    2003-07-29T23:59:59.000Z

    A chamber for trapping soil gases as they evolve from the soil without disturbance to the soil and to the natural microclimate within the chamber has been invented. The chamber opens between measurements and therefore does not alter the metabolic processes that influence soil gas efflux rates. A multiple chamber system provides for repetitive multi-point sampling, undisturbed metabolic soil processes between sampling, and an essentially airtight sampling chamber operating at ambient pressure.

  14. Chemical Evolution and Chemical State of the Long Valley Magma Chamber |

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia:PowerCER.png El CER es unaChelmsford, Massachusetts: EnergyOpen Energy

  15. RESEARCH ARTICLE Bubble growth in visco-elastic magma: implications

    E-Print Network [OSTI]

    Lyakhovsky, Vladimir

    RESEARCH ARTICLE Bubble growth in visco-elastic magma: implications to magma fragmentation modulus, bubble growth is slow and follows an exponential law in a viscous growth regime, while for low friction and the Mohr-Coulomb failure theory, and a strain related one based on fibre elongation

  16. Liquid Wall Chambers

    SciTech Connect (OSTI)

    Meier, W R

    2011-02-24T23:59:59.000Z

    The key feature of liquid wall chambers is the use of a renewable liquid layer to protect chamber structures from target emissions. Two primary options have been proposed and studied: wetted wall chambers and thick liquid wall (TLW) chambers. With wetted wall designs, a thin layer of liquid shields the structural first wall from short ranged target emissions (x-rays, ions and debris) but not neutrons. Various schemes have been proposed to establish and renew the liquid layer between shots including flow-guiding porous fabrics (e.g., Osiris, HIBALL), porous rigid structures (Prometheus) and thin film flows (KOYO). The thin liquid layer can be the tritium breeding material (e.g., flibe, PbLi, or Li) or another liquid metal such as Pb. TLWs use liquid jets injected by stationary or oscillating nozzles to form a neutronically thick layer (typically with an effective thickness of {approx}50 cm) of liquid between the target and first structural wall. In addition to absorbing short ranged emissions, the thick liquid layer degrades the neutron flux and energy reaching the first wall, typically by {approx}10 x x, so that steel walls can survive for the life of the plant ({approx}30-60 yrs). The thick liquid serves as the primary coolant and tritium breeding material (most recent designs use flibe, but the earliest concepts used Li). In essence, the TLW places the fusion blanket inside the first wall instead of behind the first wall.

  17. Secondary emission gas chamber

    E-Print Network [OSTI]

    V. In'shakov; V. Kryshkin; V. Skvortsov

    2014-12-10T23:59:59.000Z

    For a hadron calorimeter active element there is considered a gaseous secondary emis-sion detector (150 micron gap, 50 kV/cm). Such one-stage parallel plate chamber must be a radiation hard, fast and simple. A model of such detector has been produced, tested and some characteristics are presented.

  18. Multi-chamber deposition system

    DOE Patents [OSTI]

    Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

    1989-06-27T23:59:59.000Z

    A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

  19. Multi-chamber deposition system

    DOE Patents [OSTI]

    Jacobson, Richard L. (Roseville, MN); Jeffrey, Frank R. (Shoreview, MN); Westerberg, Roger K. (Cottage Grove, MN)

    1989-10-17T23:59:59.000Z

    A system for the simultaneous deposition of different coatings onto a thin web within a large volume vacuum chamber is disclosed which chamber is provided with a plurality of deposition chambers in which the different layers are deposited onto the film as its moves from a supply roll to a finished take-up roll of coated web. The deposition chambers provided within the large vacuum chamber are provided with separate seals which minimize back diffusion of any dopant gas from adjacent deposition chambers.

  20. Session 6: Magma Energy: Engineering Feasibility of Energy Extraction from Magma Bodies

    SciTech Connect (OSTI)

    Traeger, R.K.

    1983-12-01T23:59:59.000Z

    Extensive quantities of high-quality energy are estimated to be available from molten magma bodies existing within 10 Km of the US continent's surface. A five-year study sponsored by DOE/BES demonstrated that extraction of energy from these melts was scientifically feasible. The next stage of assessment is to evaluate the engineering feasibility of energy extraction and provide a preliminary economic evaluation. Should the second step demonstrate engineering feasibility, the third step would include detailed economic, market and commercialization endeavors. Evaluation of the engineering feasibility will be initiated in FY 84 in a program supported by DOE/GHTD and managed by Dave Allen. The project will be managed by Sandia Labs in James Kelsey's Geothermal Technology Development Division. The project will continue to draw on expertise throughout the country, especially the scientific base established in the previous BES Magma Energy Program.

  1. Three chamber negative ion source

    DOE Patents [OSTI]

    Leung, Ka-Ngo (Hercules, CA); Ehlers, Kenneth W. (Alamo, CA); Hiskes, John R. (Livermore, CA)

    1985-01-01T23:59:59.000Z

    A negative ion vessel is divided into an excitation chamber, a negative ionization chamber and an extraction chamber by two magnetic filters. Input means introduces neutral molecules into a first chamber where a first electron discharge means vibrationally excites the molecules which migrate to a second chamber. In the second chamber a second electron discharge means ionizes the molecules, producing negative ions which are extracted into or by a third chamber. A first magnetic filter prevents high energy electrons from entering the negative ionization chamber from the excitation chamber. A second magnetic filter prevents high energy electrons from entering the extraction chamber from the negative ionizing chamber. An extraction grid at the end of the negative ion vessel attracts negative ions into the third chamber and accelerates them. Another grid, located adjacent to the extraction grid, carries a small positive voltage in order to inhibit positive ions from migrating into the extraction chamber and contour the plasma potential. Additional electrons can be suppressed from the output flux using ExB forces provided by magnetic field means and the extractor grid electric potential.

  2. Project EARTH-12-MH1: Quantifying mafic magma: the driver for arc volcanism

    E-Print Network [OSTI]

    Henderson, Gideon

    of mafic inclusions following magma mixing at Soufrière Hills volcano, Montserrat. Contrib Mineral Petrol

  3. Magma energy extraction - Annual Report for FY88

    SciTech Connect (OSTI)

    Dunn, J.C. (ed.)

    1989-08-01T23:59:59.000Z

    Thermal energy contained in magmatic systems represents a huge potential resource. In the US, useful energy contained in molten and partially-molten magma within the upper 10 km of the crust has been estimated at 50,000 to 500,000 Quads. The objective of the Magma Energy Extraction Program is to determine engineering feasibility of locating, accessing and utilizing magma as a viable energy resource. Engineering feasibility will depend on size and depth of the resource; extraction rates; and material life times. 11 refs., 29 figs., 1 tab.

  4. ORIGINAL PAPER Amphibole stability in primitive arc magmas: effects

    E-Print Network [OSTI]

    Skemer, Philip

    Miner Petrol 145:515­533; 2003) has been supplemented with addi- tional experimental data at 500 MPa Petrol DOI 10.1007/s00410-012-0740-x #12;of these compositions represent examples of hydrous magmas

  5. Ionization chamber dosimeter

    DOE Patents [OSTI]

    Renner, Tim R. (Berkeley, CA); Nyman, Mark A. (Berkeley, CA); Stradtner, Ronald (Kensington, CA)

    1991-01-01T23:59:59.000Z

    A method for fabricating an ion chamber dosimeter collecting array of the type utilizing plural discrete elements formed on a uniform collecting surface which includes forming a thin insulating layer over an aperture in a frame having surfaces, forming a predetermined pattern of through holes in the layer, plating both surfaces of the layer and simultaneously tilting and rotating the frame for uniform plate-through of the holes between surfaces. Aligned masking and patterned etching of the surfaces provides interconnects between the through holes and copper leads provided to external circuitry.

  6. Neutron Detection via Bubble Chambers

    SciTech Connect (OSTI)

    Jordan, David V.; Ely, James H.; Peurrung, Anthony J.; Bond, Leonard J.; Collar, J. I.; Flake, Matthew; Knopf, Michael A.; Pitts, W. K.; Shaver, Mark W.; Sonnenschein, Andrew; Smart, John E.; Todd, Lindsay C.

    2005-10-06T23:59:59.000Z

    The results of a Pacific Northwest National Laboratory (PNNL) exploratory research project investigating the feasibility of fast neutron detection using a suitably prepared and operated, pressure-cycled bubble chamber are described. The research was conducted along two parallel paths. Experiments with a slow pressure-release Halon chamber at the Enrico Fermi Institute at the University of Chicago showed clear bubble nucleation sensitivity to an AmBe neutron source and insensitivity to the 662 keV gammas from a 137Cs source. Bubble formation was documented via high-speed (1000 frames/sec) photography, and the acoustic signature of bubble formation was detected using a piezo-electric transducer element mounted on the base of the chamber. The chamber’s neutron sensitivity as a function of working fluid temperature was mapped out. The second research path consisted of the design, fabrication, and testing of a fast pressure-release Freon-134a chamber at PNNL. The project concluded with successful demonstrations of the PNNL chamber’s AmBe neutron source sensitivity and 137Cs gamma insensitivity. The source response tests of the PNNL chamber were documented with high-speed photography.

  7. Ion chamber based neutron detectors

    DOE Patents [OSTI]

    Derzon, Mark S; Galambos, Paul C; Renzi, Ronald F

    2014-12-16T23:59:59.000Z

    A neutron detector with monolithically integrated readout circuitry, including: a bonded semiconductor die; an ion chamber formed in the bonded semiconductor die; a first electrode and a second electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; and the readout circuitry which is electrically coupled to the first and second electrodes. The bonded semiconductor die includes an etched semiconductor substrate bonded to an active semiconductor substrate. The readout circuitry is formed in a portion of the active semiconductor substrate. The ion chamber has a substantially planar first surface on which the first electrode is formed and a substantially planar second surface, parallel to the first surface, on which the second electrode is formed. The distance between the first electrode and the second electrode may be equal to or less than the 50% attenuation length for neutrons in the neutron absorbing material filling the ion chamber.

  8. A note on axial symmetries

    E-Print Network [OSTI]

    Christopher Beetle; Shawn Wilder

    2013-12-31T23:59:59.000Z

    This note describes a local scheme to characterize and normalize an axial Killing field on a general Riemannian geometry. No global assumptions are necessary, such as that the orbits of the Killing field all have period $2 \\pi$. Rather, any Killing field that vanishes at at least one point necessarily has the expected global properties.

  9. Magma energy research project: state-of-the-project report, October 1, 1978

    SciTech Connect (OSTI)

    Colp, J.L.; Traeger, R.K.

    1980-02-01T23:59:59.000Z

    The feasibility of extracting energy from magma bodies is investigated. The work done in FY 76, 77, and 78 in the following tasks are summarized; resource location and definition, source tapping, magma characterization and materials compatibility, and energy extraction. (MHR)

  10. Petrology of some oceanic island basalts: PRIMELT2.XLS software for primary magma calculation

    E-Print Network [OSTI]

    Petrology of some oceanic island basalts: PRIMELT2.XLS software for primary magma calculation C potential temperature; primary magma. Index Terms: 3621 Mineralogy and Petrology: Mantle processes (1038); 3610 Mineralogy and Petrology: Geochemical modeling (1009, 8410); 3630 Mineralogy and Petrology

  11. Electrochemical cell apparatus having axially distributed entry of a fuel-spent fuel mixture transverse to the cell lengths

    DOE Patents [OSTI]

    Reichner, P.; Dollard, W.J.

    1991-01-08T23:59:59.000Z

    An electrochemical apparatus is made having a generator section containing axially elongated electrochemical cells, a fresh gaseous feed fuel inlet, a gaseous feed oxidant inlet, and at least one gaseous spent fuel exit channel, where the spent fuel exit channel passes from the generator chamber to combine with the fresh feed fuel inlet at a mixing apparatus, reformable fuel mixture channel passes through the length of the generator chamber and connects with the mixing apparatus, that channel containing entry ports within the generator chamber, where the axis of the ports is transverse to the fuel electrode surfaces, where a catalytic reforming material is distributed near the reformable fuel mixture entry ports. 2 figures.

  12. Proposed Studentship Investigating the interaction of magma plumbing systems

    E-Print Network [OSTI]

    Royal Holloway, University of London

    of mineral grains and use this to suggest possible magma plumbing configurations. · Use diffusion profiling and melt extraction at one centre can destabilize the magmatic system sufficiently to trigger eruptions of analytical techniques specifically analysis of small aliquots from zoned minerals for isotope analyses, major

  13. A theoretical model of the explosive fragmentation of vesicular magma

    E-Print Network [OSTI]

    McGuinness, Mark

    fire fountaining to vigorous Vulcanian and Plinian eruptions. The range of different types of explosiveA theoretical model of the explosive fragmentation of vesicular magma A. C. Fowler, MACSI explosion can occur, and is motivated by the corresponding phenomenon of magmatic explosion during Vulcanian

  14. The TESLA Time Projection Chamber

    E-Print Network [OSTI]

    Nabil Ghodbane

    2002-12-12T23:59:59.000Z

    A large Time Projection Chamber is proposed as part of the tracking system for a detector at the TESLA electron positron linear collider. Different ongoing R&D studies are reviewed, stressing progress made on a new type readout technique based on Micro-Pattern Gas Detectors.

  15. VERTEX CHAMBERS TARGET CELL CALORIMETER

    E-Print Network [OSTI]

    DRIFT VC 1/2 FC 1/2 VERTEX CHAMBERS TARGET CELL DVC MC 1­3 HODOSCOPE H0 MONITOR BC 1/2 BC 3/4 TRD at Threashold Lambda Physics (u ­L spin transfer) Motivation: ­ W L Target cell e beam L p p e ­ Elastic: Peltier elements ( T ~ ­20C ) ­ Custom built electronics + HELIX chips low autgassing (

  16. Chamber dynamic research with pulsed power

    SciTech Connect (OSTI)

    PETERSON,ROBERT R.; OLSON,CRAIG L.; RENK,TIMOTHY J.; ROCHAU,GARY E.; SWEENEY,MARY ANN

    2000-05-15T23:59:59.000Z

    In Inertial Fusion Energy (IFE), Target Chamber Dynamics (TCD) is an integral part of the target chamber design and performance. TCD includes target output deposition of target x-rays, ions and neutrons in target chamber gases and structures, vaporization and melting of target chamber materials, radiation-hydrodynamics in target chamber vapors and gases, and chamber conditions at the time of target and beam injections. Pulsed power provides a unique environment for IFE-TCD validation experiments in two important ways: they do not require the very clean conditions which lasers need and they currently provide large x-ray and ion energies.

  17. Characteristics of the upper crust and magma chambers along the spreading centers of the Lau back-arc basin

    E-Print Network [OSTI]

    Dingler, Allison Maria Jacobs

    2007-01-01T23:59:59.000Z

    locations we create a vehicle to quickly recognize potential geo-hazardouslocation of the 25 most populated cities in the world, we can identify the most potentially geo-hazardous

  18. Characteristics of the upper crust and magma chambers along the spreading centers of the Lau back-arc basin

    E-Print Network [OSTI]

    Dingler, Allison Maria Jacobs

    2007-01-01T23:59:59.000Z

    G. , 1990. Origin of petrology and geochemistry of submarinerate, morphology, and petrology. Upper crustal refractione.g. , morphology, petrology, seismicity, and hydrothermal

  19. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, Bruce E. (Los Alamos, NM)

    1997-01-01T23:59:59.000Z

    Electron orbits from a helical axial wiggler in an axial guide field are absolutely unstable as power is extracted from the particles. For off-axis beams an axial FEL mechanism exists when the axial electric field in a TM mode is wiggled to interact with the axial velocity of the electrons that form the beam. The interaction strength is comparable to that for helical FELs and is insensitive to beam orbit errors. The orbits for this mechanism are extremely stable in the absence of space charge and lead to high extraction efficiencies without particle phasing incoherence or interception. This interaction mechanism is suitable for use with intense annular electron beams for high power generation at microwave frequencies.

  20. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, B.E.

    1997-09-02T23:59:59.000Z

    Electron orbits from a helical axial wiggler in an axial guide field are absolutely unstable as power is extracted from the particles. For off-axis beams an axial FEL mechanism exists when the axial electric field in a TM mode is wiggled to interact with the axial velocity of the electrons that form the beam. The interaction strength is comparable to that for helical FELs and is insensitive to beam orbit errors. The orbits for this mechanism are extremely stable in the absence of space charge and lead to high extraction efficiencies without particle phasing incoherence or interception. This interaction mechanism is suitable for use with intense annular electron beams for high power generation at microwave frequencies. 5 figs.

  1. The Magma Energy Exploratory Well | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f <MaintainedInformation 2EnergyCityGreen Data Book JumpMagma Energy

  2. Flow Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY); LaBelle, James (Murrieta, CA)

    2000-02-22T23:59:59.000Z

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. An axially aligned outlet may also increase the flow efficiency. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane. A seal separator may increase the useful life of the seal between the fixed and rotatable portions.

  3. The central Kenya peralkaline province: Insights into the evolution of peralkaline salic magmas

    E-Print Network [OSTI]

    Boyer, Edmond

    The central Kenya peralkaline province: Insights into the evolution of peralkaline salic magmas Ra rue de la Férollerie, 45071 Orléans cedex 2, France Abstract The central Kenya peralkaline processes is summarized. Keywords: Kenya; Petrogenesis; Peralkaline magmas 1. Introduction In the central

  4. MAGMA MIC 1.3 Release Optimizing Linear Algebra for Applications on

    E-Print Network [OSTI]

    Tennessee, University of

    generation LAPACK / ScaLAPACK ­ Programming models, and ­ Technologies for heterogeneous Intel Xeon Phi;Key Features of MAGMA MIC PERFORMANCE & ENERGY EFFICIENCY MAGMA MIC 1.3 1 GFlop / Watt 3 GFlop / Watt/AO interface · MIC/Native interface · Multiple precision support · Mixed-precision iter. refinement solvers

  5. PLASMA GPU MAGMA Rendimiento Trabajo Futuro Matrix Algebra on GPU and Multicore Architecture

    E-Print Network [OSTI]

    Giménez, Domingo

    PLASMA GPU MAGMA Rendimiento Trabajo Futuro MAGMA Matrix Algebra on GPU and Multicore Architecture? Parallel Linear Algebra for Scalable Multi-core Architectures. Obtener el máximo rendimiento de lineales y mínimos cuadrados LU, Cholesky, QR & LQ Sistemas lineales de tipos de datos combinados LU

  6. Direct numerical simulation of an iron rain in the magma ocean

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    investigate the conversion of gravitational energy into viscous heating and the thermal equilibration betweenDirect numerical simulation of an iron rain in the magma ocean H. Ichikawa,1,2 S. Labrosse,1 and K of metal in a magma ocean. The model, using a fully Lagrangian approach called the moving particle semi

  7. Generation of CO2-rich melts during basalt magma ascent and degassing

    E-Print Network [OSTI]

    Boyer, Edmond

    to solubilities. In contrast, the rate of vesiculation controls the final melt CO2 concentration. HighGeneration of CO2-rich melts during basalt magma ascent and degassing Michel Pichavant . Ida Di magma degassing, continuous decompressions of volatile-bearing (2.7-3.8 wt% H2O, 600-1300 ppm CO2

  8. Performance limits of axial turbomachine stages

    E-Print Network [OSTI]

    Hall, David Kenneth

    2011-01-01T23:59:59.000Z

    This thesis assesses the limits of stage efficiency for axial compressor and turbine stages. A stage model is developed, consisting of a specified geometry and a surface velocity distribution with turbulent boundary layers. ...

  9. TRU waste characterization chamber gloveboxes.

    SciTech Connect (OSTI)

    Duncan, D. S.

    1998-07-02T23:59:59.000Z

    Argonne National Laboratory-West (ANL-W) is participating in the Department of Energy's (DOE) National Transuranic Waste Program in support of the Waste Isolation Pilot Plant (WIPP). The Laboratory's support currently consists of intrusive characterization of a selected population of drums containing transuranic waste. This characterization is performed in a complex of alpha containment gloveboxes termed the Waste Characterization Gloveboxes. Made up of the Waste Characterization Chamber, Sample Preparation Glovebox, and the Equipment Repair Glovebox, they were designed as a small production characterization facility for support of the Idaho National Engineering and Environmental Laboratory (INEEL). This paper presents salient features of these gloveboxes.

  10. Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E. (Laramie, WY); Lindberg, William R. (Laramie, WY); Burgess, Robert K. (Sheridan, WY)

    2000-08-29T23:59:59.000Z

    The present invention provides an axially-rotated valve which permits increased flow rates and lower pressure drop (characterized by a lower loss coefficient) by using an axial eccentric split venturi with two portions where at least one portion is rotatable with respect to the other portion. The axially-rotated valve typically may be designed to avoid flow separation and/or cavitation at full flow under a variety of conditions. Similarly, the valve is designed, in some embodiments, to produce streamlined flow within the valve. A typical cross section of the eccentric split venturi may be non-axisymmetric such as a semicircular cross section which may assist in both throttling capabilities and in maximum flow capacity using the design of the present invention. Such a design can include applications for freeze resistant axially-rotated valves and may be fully-opened and fully-closed in one-half of a complete rotation. An internal wide radius elbow typically connected to a rotatable portion of the eccentric venturi may assist in directing flow with lower friction losses. A valve actuator may actuate in an axial manner yet be uniquely located outside of the axial flow path to further reduce friction losses. A seal may be used between the two portions that may include a peripheral and diametrical seal in the same plane.

  11. Fluidized wall for protecting fusion chamber walls

    DOE Patents [OSTI]

    Maniscalco, James A. (Danville, CA); Meier, Wayne R. (Livermore, CA)

    1982-01-01T23:59:59.000Z

    Apparatus for protecting the inner wall of a fusion chamber from microexplosion debris, x-rays, neutrons, etc. produced by deuterium-tritium (DT) targets imploded within the fusion chamber. The apparatus utilizes a fluidized wall similar to a waterfall comprising liquid lithium or solid pellets of lithium-ceramic, the waterfall forming a blanket to prevent damage of the structural materials of the chamber.

  12. Electrochemical cell apparatus having axially distributed entry of a fuel-spent fuel mixture transverse to the cell lengths

    DOE Patents [OSTI]

    Reichner, Philip (Plum Borough, PA); Dollard, Walter J. (Churchill Borough, PA)

    1991-01-01T23:59:59.000Z

    An electrochemical apparatus (10) is made having a generator section (22) containing axially elongated electrochemical cells (16), a fresh gaseous feed fuel inlet (28), a gaseous feed oxidant inlet (30), and at least one gaseous spent fuel exit channel (46), where the spent fuel exit channel (46) passes from the generator chamber (22) to combine with the fresh feed fuel inlet (28) at a mixing apparatus (50), reformable fuel mixture channel (52) passes through the length of the generator chamber (22) and connects with the mixing apparatus (50), that channel containing entry ports (54) within the generator chamber (22), where the axis of the ports is transverse to the fuel electrode surfaces (18), where a catalytic reforming material is distributed near the reformable fuel mixture entry ports (54).

  13. Magma simulation facility design considerations, capabilities, and operational considerations

    SciTech Connect (OSTI)

    Wemple, R.P.

    1981-04-01T23:59:59.000Z

    The high-pressure, high temperature (60 Kpsi or 413.6 MPa/1600/sup 0/C) facility described is being used for molten rock (magma) experiments and metallurgical pressure bonding experiments. The unique design of the facility will accommodate samples as large as 10 cm dia. by 10 cm in height in an isothermal (+-4/sup 0/C at 1400/sup 0/C and 44 Kpsi or 303.3 MPa) cylindrical hot zone. The facility history, capabilities, and operational considerations are thoroughly discussed with appropriate illustrations. Since the system-contained energy while operating is approximately 1 x 10/sup 6/ ft-lbs (1.356 x 10/sup 6/ N-m) or 0.7 lbs (318 g) TNT equivalent, considerable discussion is related to hazards analysis and protection of the equipment and the operating personnel from damage caused by nonstandard conditions (interrupted H/sub 2/O flow, power outage, overpressure, etc.).

  14. The Mark II Vertex Drift Chamber

    SciTech Connect (OSTI)

    Alexander, J.P.; Baggs, R.; Fujino, D.; Hayes, K.; Hoard, C.; Hower, N.; Hutchinson, D.; Jaros, J.A.; Koetke, D.; Kowalski, L.A.

    1989-03-01T23:59:59.000Z

    We have completed constructing and begun operating the Mark II Drift Chamber Vertex Detector. The chamber, based on a modified jet cell design, achieves 30 {mu}m spatial resolution and <1000 {mu}m track-pair resolution in pressurized CO{sub 2} gas mixtures. Special emphasis has been placed on controlling systematic errors including the use of novel construction techniques which permit accurate wire placement. Chamber performance has been studied with cosmic ray tracks collected with the chamber located both inside and outside the Mark II. Results on spatial resolution, average pulse shape, and some properties of CO{sub 2} mixtures are presented. 10 refs., 12 figs., 1 tab.

  15. FY 1984 and FY 1985 geochemistry and materials studies in support of the Magma Energy Extraction Program

    SciTech Connect (OSTI)

    Westrich, H.R.; Weirick, L.J.; Cygan, R.T.; Reece, M.; Hlava, P.F.; Stockman, H.W.; Gerlach, T.M.

    1986-04-01T23:59:59.000Z

    Geochemistry and materials studies are being performed in support of the Magma Energy Extraction Program. The work is largely restricted to: (1) characterizing magmatic environments at sites of interest, (2) testing engineering materials in laboratory simulated magmatic environments, (3) investigating chemical mass transport effects inherent in designs for direct contact heat exchangers, and (4) evaluating degassing hazards associated with drilling into and extracting energy from shallow magma. Magma characterization studies have been completed for shallow magma at Long Valley, Coso volcanic field, and Kilauea volcano. The behavior of 17 commercially available materials has been examined in rhyolite magma at 850/sup 0/C and 200 MPa for periods up to seven days. Analysis of reaction products from materials tests to date indicate that oxidation is the main corrosion problem for most alloys in rhyolitic magma. Considerations of corrosion resistance, high-temperature strength, and cost indicate nickel-base superalloys offer the most promise as candidates for use in rhyolitic magma.

  16. Temperature Studies for ATLAS MDT BOS Chambers

    E-Print Network [OSTI]

    A. Engl; O. Biebel; R. Hertenberger; R. Mameghani; D. Merkl; F. Rauscher; D. Schaile; R. Stroehmer

    2009-08-11T23:59:59.000Z

    Data sets with high statistics taken at the cosmic ray facility, equipped with 3 ATLAS BOS MDT chambers, in Garching (Munich) have been used to study temperature and pressure effects on gas gain and drifttime. The deformation of a thermally expanded chamber was reconstructed using the internal RasNik alignment monitoring system and the tracks from cosmic data. For these studies a heating system was designed to increase the temperature of the middle chamber by up to 20 Kelvins over room temperature. For comparison the temperature effects on gas properties have been simulated with Garfield. The maximum drifttime decreased under temperature raise by -2.21 +- 0.08 ns/K, in agreement with the results of pressure variations and the Garfield simulation. The increased temperatures led to a linear increase of the gas gain of about 2.1% 1/K. The chamber deformation has been analyzed with the help of reconstructed tracks. By the comparison of the tracks through the reference chambers with these through the test chamber the thermal expansion has been reconstructed and the result shows agreement with the theoretical expansion coefficient. As the wires are fixed at the end of the chamber, the wire position calculation can not provide a conclusion for the chamber middle. The complete deformation has been identified with the analysis of the monitoring system RasNik, whose measured values have shown a homogeneous expansion of the whole chamber, overlayed by a shift and a rotation of the chamber middle with respect to the outer part of the chamber. The established results of both methods are in agreement. We present as well a model for the position-drifttime correction as function of temperature.

  17. Nucleon Axial Form Factor from Lattice QCD

    E-Print Network [OSTI]

    Liu, K F; Draper, T; Wu, J M; Wilcox, W

    1994-01-01T23:59:59.000Z

    Results for the isovector axial form factors of the proton from a lattice QCD calculation are presented for both point-split and local currents. They are obtained on a quenched $16^{3} \\times 24$ lattice at $\\beta= 6.0$ with Wilson fermions for a range of quark masses from strange to charm. We determine the finite lattice renormalization for both the local and point-split currents of heavy quarks. Results extrapolated to the chiral limit show that the $q^2$ dependence of the axial form factor agrees reasonably well with experiment. The axial coupling constant $g_A$ calculated for the local and the point-split currents is about 6\\% and 12\\% smaller than the experimental value respectively.

  18. IFE Chamber Technology Testing Program In NIF and Chamber Development Test Plan Mohamed A. Abdou

    E-Print Network [OSTI]

    Abdou, Mohamed

    IFE Chamber Technology Testing Program In NIF and Chamber Development Test Plan Mohamed A. Abdou chamber technology testing program in NIF involoving: criteria for evaluation and costs of the more complex experiments in NIF. I. Introduction One important class of issues concerning

  19. A Time Projection Chamber for High Accuracy and Precision Fission Cross-Section Measurements

    SciTech Connect (OSTI)

    T. Hill; K. Jewell; M. Heffner; D. Carter; M. Cunningham; V. Riot; J. Ruz; S. Sangiorgio; B. Seilhan; L. Snyder; D. M. Asner; S. Stave; G. Tatishvili; L. Wood; R. G. Baker; J. L. Klay; R. Kudo; S. Barrett; J. King; M. Leonard; W. Loveland; L. Yao; C. Brune; S. Grimes; N. Kornilov; T. N. Massey; J. Bundgaard; D. L. Duke; U. Greife; U. Hager; E. Burgett; J. Deaven; V. Kleinrath; C. McGrath; B. Wendt; N. Hertel; D. Isenhower; N. Pickle; H. Qu; S. Sharma; R. T. Thornton; D. Tovwell; R. S. Towell; S.

    2014-09-01T23:59:59.000Z

    The fission Time Projection Chamber (fissionTPC) is a compact (15 cm diameter) two-chamber MICROMEGAS TPC designed to make precision cross-section measurements of neutron-induced fission. The actinide targets are placed on the central cathode and irradiated with a neutron beam that passes axially through the TPC inducing fission in the target. The 4p acceptance for fission fragments and complete charged particle track reconstruction are powerful features of the fissionTPC which will be used to measure fission cross-sections and examine the associated systematic errors. This paper provides a detailed description of the design requirements, the design solutions, and the initial performance of the fissionTPC.

  20. doi:10.1038/nature04507 Uplift, Thermal Unrest, and Magma Intrusion at

    E-Print Network [OSTI]

    of the caldera floor connecting the two resurgent domes (Sour Creek, SC and Mallard Lake, ML, in Fig. 1) changed-sealed and leaking hydrothermal fluid reservoir that traps volatiles exsolved from a crystallizing rhyolitic magma7

  1. Xenocryst assimilation and formation of peritectic crystals during magma contamination: An experimental study

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Xenocryst assimilation and formation of peritectic crystals during magma contamination Minéralogie, Switzerland c Dalhousie University, Department of Earth Sciences, Canada Abstract Contamination and peritectic crystals that form through incongruent melting or dissolution of the original contaminants

  2. Rapid-quench axially staged combustor

    DOE Patents [OSTI]

    Feitelberg, Alan S. (Niskayuna, NY); Schmidt, Mark Christopher (Niskayuna, NY); Goebel, Steven George (Clifton Park, NY)

    1999-01-01T23:59:59.000Z

    A combustor cooperating with a compressor in driving a gas turbine includes a cylindrical outer combustor casing. A combustion liner, having an upstream rich section, a quench section and a downstream lean section, is disposed within the outer combustor casing defining a combustion chamber having at least a core quench region and an outer quench region. A first plurality of quench holes are disposed within the liner at the quench section having a first diameter to provide cooling jet penetration to the core region of the quench section of the combustion chamber. A second plurality of quench holes are disposed within the liner at the quench section having a second diameter to provide cooling jet penetration to the outer region of the quench section of the combustion chamber. In an alternative embodiment, the combustion chamber quench section further includes at least one middle region and at least a third plurality of quench holes disposed within the liner at the quench section having a third diameter to provide cooling jet penetration to at least one middle region of the quench section of the combustion chamber.

  3. Melt zones beneath five volcanic complexes in California: an assessment of shallow magma occurrences

    SciTech Connect (OSTI)

    Goldstein, N.E.; Flexser, S.

    1984-12-01T23:59:59.000Z

    Recent geological and geophysical data for five magma-hydrothermal systems were studied for the purpose of developing estimates for the depth, volume and location of magma beneath each area. The areas studied were: (1) Salton Trough, (2) The Geysers-Clear Lake, (3) Long Valley caldera, (4) Coso volcanic field, and (5) Medicine Lake volcano, all located in California and all selected on the basis of recent volcanic activity and published indications of crustal melt zones. 23 figs.

  4. Commissioning of SLAC SLD 45-Degree Chambers

    E-Print Network [OSTI]

    V. O. Eschenburg

    2002-07-30T23:59:59.000Z

    The SLD experiment at the Stanford Linear Accelerator Center had a significant gap in its muon tracking coverage, provided by the Warm Iron Calorimeter. Supplemental planes of limited streamer tube chambers were added to improve the coverage in the vicinity of the gap at 0.65 commissioning of the forty-five degree chamber region of the SLAC SLD Warm Iron Calorimeter is presented. This task involved the completion of the forty-five degree chamber region geometry for the Warm Iron Calorimeter's fitter and swimmer and the changing of the way multiple scattering effects are treated in the fitter algorithm.

  5. Simulation of chamber transport for heavy-ion fusion

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Simulation of Chamber Transport for Heavy-Ion Fusion W. M.et al. , “Modeling Chamber Transport for Heavy-Ion Fusion,”et al. , "Chamber Transport of `Foot' Pulses for Heavy-Ion

  6. Intense ion beam propagation in a reactor sized chamber

    E-Print Network [OSTI]

    Vay, J.L.; Deutsch, C.

    2000-01-01T23:59:59.000Z

    beams in a heavy ion fusion reactor chamber filled with lowIon Fusion, Intense Ion Beams, Reaction Chamber. P.A.C.S.heavy ion beam propagation in the reaction chamber, Fus.

  7. Modeling chamber transport for heavy-ion fusion

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Modeling Chamber Transport for Heavy-Ion Fusion W. M. Sharp,Peterson, "Chamber Transport of 'Foot' Pulses for Heavy-Ionstate of beam ions. Although several chamber- transport

  8. Chamber transport of "foot" pulses for heavy-ion fusion

    E-Print Network [OSTI]

    Sharp, W.M.; Callahan-Miller, D.A.; Tabak, M.; Yu, S.S.; Peterson, P.F.

    2002-01-01T23:59:59.000Z

    Neutralization on Heavy-Ion-Fusion Chamber Transport," to beChamber transport of "foot" pulses for heavy-ion fusion W.chamber-transport effectiveness is the fraction of enclosed beam ions

  9. Description of Axial Detail for ROK Fuel

    SciTech Connect (OSTI)

    Trellue, Holly R [Los Alamos National Laboratory; Galloway, Jack D [Los Alamos National Laboratory

    2012-04-20T23:59:59.000Z

    For the purpose of NDA simulations of the ROK fuel assemblies, we have developed an axial burnup distribution to represent the pins themselves based on gamma scans of rods in the G23 assembly. For the purpose of modeling the G23 assembly (both at ORNL and LANL), the pin-by-pin burnup map as simulated by ROK is being assumed to represent the radial burnup distribution. However, both DA and NDA results indicate that this simulated estimate is not 100% correct. In particular, the burnup obtained from the axial gamma scan of 7 pins does not represent exactly the same 'average' pin burnup as the ROK simulation. Correction for this discrepancy is a goal of the well-characterized assembly task but will take time. For now, I have come up with a correlation for 26 axial points of the burnup as obtained by gamma scans of 7 different rods (C13, G01, G02, J11, K10, L02, and M04, neglecting K02 at this time) to the average burnup given by the simulation for each of the rods individually. The resulting fraction in each axial zone is then averaged for the 7 different rods so that it can represent every fuel pin in the assembly. The burnup in each of the 26 axial zones of rods in all ROK assemblies will then be directly adjusted using this fraction, which is given in Table 1. Note that the gamma scan data given by ROK for assembly G23 included a length of {approx}3686 mm, so the first 12 mm and the last 14 mm were ignored to give an actual rod length of {approx}366 cm. To represent assembly F02 in which no pin-by-pin burnup distribution is given by ROK, we must model it using infinitely-reflected geometry but can look at the effects of measuring in different axial zones by using intermediate burnup files (i.e. smaller burnups than 28 GWd/MTU) and determining which axial zone(s) each burnup represents. Details for assembly F02 are then given in Tables 2 and 3, which is given in Table 1 and has 44 total axial zones to represent the top meter in explicit detail in addition to the other 26 zones. Note that the MCNP files for F02 were created using the Monte Carlo burnup linkage code Monteburns, which saves MCNP input files with detailed compositions as a function of burnup. The 'intermediate burnup files' produced for F02 include a cooling time of 27 years. The axial location of 5 spacers was also included in the ROK F02 assembly in which each spacer contained a length of 3.81 cm. Note that due to the nature of Monteburns, which was run in a special fashion for this problem, the step number increments after the 27 year decay, so the second column of Table 2 refers to the step number that should be used in the Monteburns files.

  10. Review of Axial Burnup Distribution Considerations for Burnup Credit Calculations

    SciTech Connect (OSTI)

    Wagner, J.C.; DeHart, M.D.

    2000-03-01T23:59:59.000Z

    This report attempts to summarize and consolidate the existing knowledge on axial burnup distribution issues that are important to burnup credit criticality safety calculations. Recently released Nuclear Regulatory Commission (NRC) staff guidance permits limited burnup credit, and thus, has prompted resolution of the axial burnup distribution issue. The reactivity difference between the neutron multiplication factor (keff) calculated with explicit representation of the axial burnup distribution and keff calculated assuming a uniform axial burnup is referred to as the ``end effect.'' This end effect is shown to be dependent on many factors, including the axial-burnup profile, total accumulated burnup, cooling time, initial enrichment, assembly design, and the isotopics considered (i.e., actinide-only or actinides plus fission products). Axial modeling studies, efforts related to the development of axial-profile databases, and the determination of bounding axial profiles are also discussed. Finally, areas that could benefit from further efforts are identified.

  11. Field Examples of Axial Cracked Bearings in Wind Turbine Gearboxes...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Field Examples of Axial Cracked Bearings in Wind Turbine Gearboxes Presented by Paul John Baker of FrontierPro Services at the Wind Turbine Tribology Seminar 2014. 141030 Axial...

  12. An environmental sample chamber for reliable scanning transmission...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    environmental sample chamber for reliable scanning transmission x-ray microscopy measurements under water vapor. An environmental sample chamber for reliable scanning transmission...

  13. Mini-PROTEAN Multi-Casting Chamber

    E-Print Network [OSTI]

    Raizada, Manish N.

    ºC for future use. 1.2 Specifications Materials of construction Clamps Glass filled polycarbonate Casting chamber, sealing plate Molded polycarbonate Gasket Silicone tubing Overall size 10 cm x 10 cm x 16

  14. Formation mechanisms of combustion chamber deposits

    E-Print Network [OSTI]

    O'Brien, Christopher J. (Christopher John)

    2001-01-01T23:59:59.000Z

    Combustion chamber deposits are found in virtually all internal combustion engines after a few hundred hours of operation. Deposits form on cylinder, piston, and head surfaces that are in contact with fuel-air mixture ...

  15. Main Chamber Pressure why do we care about it?

    E-Print Network [OSTI]

    Pitcher, C. S.

    .main chamber recycling 3.ion flux to the upper part of the outer plate 4.upper divertor leakage #12Main Chamber Pressure why do we care about it? - neutrals in the main chamber imply a particle-surface interaction there which may result in impurity production and erosion - neutrals in the main chamber may

  16. PROJECT SUMMARY The process of generation, segregation, ascent and emplacement of granite magma during orogeny has important

    E-Print Network [OSTI]

    Solar, Gary S.

    PROJECT SUMMARY The process of generation, segregation, ascent and emplacement of granite magma and we also understand well how granite magma is emplaced in both extensional and contractional tectonic, petrography, geochronology and geochemistry of leucosomes in migmatites and in associated granite plutons

  17. Dynamics of metal-silicate separation in a terrestrial magma Tobias Hoink, Jorg Schmalzl, and Ulrich Hansen

    E-Print Network [OSTI]

    Schmalzl, Jörg

    Dynamics of metal-silicate separation in a terrestrial magma ocean Tobias Ho¨ink, Jo¨rg Schmalzl-48149 Mu¨nster, Germany (hoeink@earth.uni-muenster.de) [1] In a terrestrial magma ocean, the metal-silicate the separation of metal droplets from the liquid silicate, occurs on a characteristic timescale, which

  18. Magnetite-bubble aggregates at mixing interfaces in andesite magma bodies

    E-Print Network [OSTI]

    Edmonds, M.; Brett, A.; Herd, R. A.; Humphreys, M. C. S.; Woods, A.

    2014-08-14T23:59:59.000Z

    of Arc Magmas” 18 BLUNDY, J. & CASHMAN, K. V. 2008. Petrologic reconstruction of magmatic system 553 variables and processes. Reviews in Mineralogy and Geochemistry 69, 1, 179–239. 554 BOORMAN, S., BOUDREAU, A., & KRUGER, F. J. 2004. The lower zone... . Contributions to Mineralogy and Petrology, 156, 745–562 763. 563 CLYNNE, M. A. 1999. A complex magma mixing origin for rocks erupted in 1915, Lassen 564 Peak, California. Journal of Petrology 40, 1, 105–132. 565 COSTA, A., WADGE, G., STEWART...

  19. WIMP identification through a combined measurement of axial and scalar couplings

    E-Print Network [OSTI]

    Bertone, G; Collar, J I; Odom, B

    2007-01-01T23:59:59.000Z

    We study the prospects for detecting Weakly Interacting Massive Particles (WIMPs), in a number of phenomenological scenarios, with a detector composed of a target simultaneously sensitive to both spin-dependent and spin-independent couplings, as is the case of COUPP (Chicagoland Observatory for Underground Particle Physics). First, we show that sensitivity to both couplings optimizes chances of initial WIMP detection. Second, we demonstrate that in case of detection, comparison of the signal on two complementary targets, such as in COUPP CF3I and C4F10 bubble chambers, allows a significantly more precise determination of the dark matter axial and scalar couplings. This strategy would provide crucial information on the nature of the WIMPs, and possibly allow discrimination between neutralino and Kaluza-Klein dark matter.

  20. WIMP identification through a combined measurement of axial and scalar couplings

    E-Print Network [OSTI]

    G. Bertone; D. G. Cerdeno; J. I. Collar; B. Odom

    2007-07-23T23:59:59.000Z

    We study the prospects for detecting Weakly Interacting Massive Particles (WIMPs), in a number of phenomenological scenarios, with a detector composed of a target simultaneously sensitive to both spin-dependent and spin-independent couplings, as is the case of COUPP (Chicagoland Observatory for Underground Particle Physics). First, we show that sensitivity to both couplings optimizes chances of initial WIMP detection. Second, we demonstrate that in case of detection, comparison of the signal on two complementary targets, such as in COUPP CF3I and C4F10 bubble chambers, allows a significantly more precise determination of the dark matter axial and scalar couplings. This strategy would provide crucial information on the nature of the WIMPs, and possibly allow discrimination between neutralino and Kaluza-Klein dark matter.

  1. Study of casing treatment effects in axial flow compressors

    E-Print Network [OSTI]

    Schiller, Robert Neil

    1973-01-01T23:59:59.000Z

    to in- creased tip leakage between shroud and blade tip. Figure (I) shows a typical performance curve for an axial flow compressor. Note that as pressure ratio increases, the operating 'range between surge and stall is decreased, there by reducing... the surge to stall margin of the axial flow compressor. REFERENCES I 1 ~ 4 Koch, C. C. , "Experimental Evaluation of Outer Case Blowing or Bleeding of Single Stage Axial Flow Compressor". , Part IV. Rep. R 69AEG256, General Electric Co. , (NASA CR...

  2. Recent Advances in Chamber Science and Technology

    E-Print Network [OSTI]

    Abdou, Mohamed

    with RAFS Advanced: He gas cooling system with SiC/SiC Research on several advanced concepts: FLiBe, Li, Li cooled blanket system for higher thermal efficiency - High temperature gas cooled blanket system with Si Programs on Chamber/Blanket · Recent Progress on Liquid Walls - IFE & MFE - Basic Principles - Plasma

  3. Lifetime tests for MAC vertex chamber

    SciTech Connect (OSTI)

    Nelson, H.N.

    1986-07-01T23:59:59.000Z

    A vertex chamber for MAC was proposed to increase precision in the measurement of the B hadron and tau lepton lifetimes. Thin-walled aluminized mylar drift tubes were used for detector elements. A study of radiation hardness was conducted under the conditions of the proposed design using different gases and different operating conditions. (LEW)

  4. Flow of Volatile-Free and Volatile-Rich Basaltic Magmas through Elastic-Walled Dikes

    E-Print Network [OSTI]

    Al Hanbali, Ahmad

    averaged in "one-dimensional" flow tube. #12;Questions: · Can we obtain a simple 1D symmetric model) · Anisotropy 1 in horizontal and vertical rock stress #12;Elastic flow equations · Continuity equation t(m bFlow of Volatile-Free and Volatile-Rich Basaltic Magmas through Elastic-Walled Dikes O. Bokhove

  5. RAPID TIMESCALES FOR MAGMA OCEAN CRYSTALLIZATION ON THE HOWARDITE-EUCRITE-DIOGENITE PARENT BODY

    SciTech Connect (OSTI)

    Schiller, Martin; Paton, Chad; Bizzarro, Martin [Centre for Star and Planet Formation, Natural History Museum of Denmark, University of Copenhagen, Copenhagen DK-1350 (Denmark); Baker, Joel; Creech, John; Millet, Marc-Alban [School of Geography, Environment and Earth Sciences, Victoria University of Wellington, Wellington (New Zealand); Irving, Anthony [Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195 (United States)

    2011-10-10T23:59:59.000Z

    Asteroid 4 Vesta has long been postulated as the source for the howardite-eucrite-diogenite (HED) achondrite meteorites. Here we show that Al-free diogenite meteorites record variability in the mass-independent abundance of {sup 26}Mg ({sup 26}Mg*) that is correlated with their mineral chemistry. This suggests that these meteorites captured the Mg-isotopic evolution of a large-scale differentiating magma body with increasing {sup 27}Al/{sup 24}Mg during the lifespan of the short-lived {sup 26}Al nuclide (t {sub 1/2} {approx} 730,000 yr). Thus, diogenites and eucrites represent crystallization products of a large-scale magma ocean associated with the differentiation and magmatic evolution of the HED parent body. The {sup 26}Mg* composition of the most primitive diogenites requires onset of the magma ocean crystallization within 0.6{sup -0.4} {sub +0.5} Myr of solar system formation. Moreover, {sup 26}Mg* variations among diogenites and eucrites imply that near complete solidification of the HED parent body occurred within the following 2-3 Myr. Thermal models predict that such rapid cooling and magma ocean crystallization could only occur on small asteroids (<100 km), implying that 4 Vesta is not the source of the HED meteorites.

  6. UserCalc: A Web-based uranium series calculator for magma migration problems

    E-Print Network [OSTI]

    Spiegelman, Marc W.

    UserCalc: A Web-based uranium series calculator for magma migration problems M. Spiegelman Lamont] Abstract: Measured departures from secular equilibrium in the uranium series decay chains provide important U3231 Pa) and allow the user to input their own petrological insight and data to explore

  7. UserCalc: a web-based Uranium Series Calculator for magma migration problems

    E-Print Network [OSTI]

    Spiegelman, Marc W.

    UserCalc: a web-based Uranium Series Calculator for magma migration problems M. Spiegelman Lamont. Measured departures from secular equilibrium in the Uranium-series decay chains provide important to explore the behaviour of this model. The purpose of the site is to provide a tool that can spur additional

  8. Melt segregation under compaction and shear channelling: Application to granitic magma segregation in a continental crust

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Melt segregation under compaction and shear channelling: Application to granitic magma segregation in a mush submitted to both compaction and shear. It applies to a granitic melt imbedded within of melt to about 20 % in total to be extracted from the matrix. Abridged title Granitic melt segregation

  9. Magma storage conditions of the last eruption of Teide volcano (Canary Islands, Spain)

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    11 Magma storage conditions of the last eruption of Teide volcano (Canary Islands, Spain) Andújar and rheological state. insu-00447691,version1-18Jan2010 #12;33 Introduction In the Canary Islands (Spain), Teide storage depth at about 5 ± 1 km below current summit of Teide volcano. Given that the island has

  10. Flood and Shield Basalts from Ethiopia: Magmas from the African Superswell

    E-Print Network [OSTI]

    Demouchy, Sylvie

    Flood and Shield Basalts from Ethiopia: Magmas from the African Superswell BRUNO KIEFFER1, ETHIOPIA 4 DEEPARTEMENT DES SCIENCES DE LA TERRE ET DE L'ENVIRONNEMENT, UNIVERSITEE LIBRE DE BRUXELLES 50 the shield volcanoes. KEY WORDS: Ethiopia; flood basalts; shield volcanism; superswell INTRODUCTION According

  11. Description and operating procedure for magma characterization data acquisition and control system

    SciTech Connect (OSTI)

    Woodward, M H

    1982-04-01T23:59:59.000Z

    A computerized data acquisition and control system used in a Sandia National Laboratories' facility for molten rock (magma) and metallurgical pressure bonding experiments is described. The system is based on a Hewlett-Packard 9826A Desktop Computer and a Hewlett-Packard 3497A Data Acquisition/Control Unit. Operating procedures are included, and detailed instructions for implementing the procedures are given.

  12. Viscosity of magmas containing highly deformable bubbles M. Mangaa,*, M. Loewenbergb

    E-Print Network [OSTI]

    Manga, Michael

    Viscosity of magmas containing highly deformable bubbles M. Mangaa,*, M. Loewenbergb a Department The shear viscosity of a suspension of deformable bubbles dispersed within a Newtonian ¯uid is calculated. For small Ca, bubbles remain nearly spherical, and for suf®ciently large strains the viscosity of suspension

  13. The Magnetite Crisis in the Evolution of Arc-related Magmas and the Initial

    E-Print Network [OSTI]

    Lee, Cin-Ty Aeolus

    and back-arc magma series is their association with ores of the rare, but economically important metals Au of these metals is not straightforward. For Au, one of the rarest metals on Earth, with a primitive mantle RESEARCH SCHOOL OF EARTH SCIENCES, AUSTRALIAN NATIONAL UNIVERSITY, CANBERRA, ACT 0200, AUSTRALIA RECEIVED

  14. On-Site Wastewater Treatment Systems: Leaching Chambers

    E-Print Network [OSTI]

    Lesikar, Bruce J.

    2000-02-04T23:59:59.000Z

    Leaching chambers distribute treated wastewater into the soil. This publication lists the advantages and disadvantages of leaching chamber systems, explains how to maintain them and gives estimates of costs....

  15. A Transonic Axial Compressor Facility for Fundamental Research

    E-Print Network [OSTI]

    Morris, Scott C.

    A Transonic Axial Compressor Facility for Fundamental Research and Flow Control Development Joshua, IN, 46556, USA A single-stage transonic axial compressor facility has been constructed in the the current generation of aero-gas turbine engines. The compressor stage and facility were designed

  16. The Shaft Torque of a Tandem Axial-Piston Pump

    E-Print Network [OSTI]

    Manring, Noah D.

    The Shaft Torque of a Tandem Axial- Piston Pump Noah D. Manring Viral S. Mehta Mechanical of this study is to identify the best indexed position of two rotating groups within a tandem axial-piston pump characteristics of the pump, other vibration aspects of the machine are also expected to be reduced. In particular

  17. Engineering analyses of large precision cathode strip chambers for GEM

    SciTech Connect (OSTI)

    Horvath, J.A.; Belser, F.C.; Pratuch, S.M.; Wuest, C.R. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States); Mitselmakher, G. [Superconducting Super Collider Lab., Dallas, TX (United States)] [Superconducting Super Collider Lab., Dallas, TX (United States); Gordeev, A. [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation)] [Institute of Theoretical and Experimental Physics, Moscow (Russian Federation); Johnson, C.V. [Lawrence Livermore National Lab., CA (United States)] [Lawrence Livermore National Lab., CA (United States); [Superconducting Super Collider Lab., Dallas, TX (United States); Polychronakos, V.A. [Brookhaven National Lab., Upton, NY (United States)] [Brookhaven National Lab., Upton, NY (United States); Golutvin, I.A. [Joint Institute for Nuclear Research, Dubna (Russian Federation)] [Joint Institute for Nuclear Research, Dubna (Russian Federation)

    1993-10-21T23:59:59.000Z

    Structural analyses of large precision cathode strip chambers performed up to the date of this publication are documented. Mechanical property data for typical chamber materials are included. This information, originally intended to be an appendix to the {open_quotes}CSC Structural Design Bible,{close_quotes} is presented as a guide for future designers of large chambers.

  18. Chapter 7.32 Centura-MxP+ Chamber

    E-Print Network [OSTI]

    Healy, Kevin Edward

    P+ is a magnetically enhanced reactive ion etch chamber typically used for etching oxide and nitride patternsChapter 7.32 Centura-MxP+ Chamber (centura-mxp) (586) 1.0 Equipment Purpose 1.1 The Centura Mx in the wafer. 1.2 The Centura platform is a fully automated, multi-wafer capacity, multi-chamber system

  19. Overview of Chamber and Power Plant Designs for IFE

    E-Print Network [OSTI]

    Overview of Chamber and Power Plant Designs for IFE Wayne Meier Deputy Program Leader Fusion Energy power plant are illustrated here Target Factory and Injector Fusion ChamberDriver Power Conversion Review 1/30/11 4 Tritium Processing #12;There have been >50 IFE chamber design concepts and power plant

  20. Impact of beam transport method on chamber and driver design for heavy ion inertial fusion energy

    E-Print Network [OSTI]

    Rose, D.V.; Welch, D.R.; Olson, C.L.; Yu, S.S.; Neff, S.; Sharp, W.M.

    2002-01-01T23:59:59.000Z

    neutralization on heavy-ion fusion chamber transport,” totechniques for heavy ion fusion chamber transport,” Nucl.liquid heavy-ion fusion target chambers,” Fusion Technol.

  1. Geochemistry and materials studies in support of the Magma Energy Extraction Program

    SciTech Connect (OSTI)

    Westrich, H.R.; Weirick, L.J.

    1986-01-01T23:59:59.000Z

    Geochemistry and materials studies are being performed in support of the Magma Energy Extraction Program. The scope of the studies is dictated by the sites under consideration and the designs of the drilling and energy extraction systems. The work has been largely restricted to characterizing magmatic environments at sites of interest and testing engineering materials in laboratory simulated rhyolite magmatic environments. The behavior of 17 commercially available materials has been examined at magmatic conditions. Analysis of reaction products reveal that oxidation, and not sulfidation, is the main corrosion problem for most alloys in rhyolite, and that reaction with other magmatic components is limited. Considerations of corrosion resistance, high-temperature strength, and cost indicate nickel-base superalloys offer the most promise as candidates for use in rhyolitic magma.

  2. Phase 1 drilling operations at the Magma Energy Exploratory Well (LVF 51-20)

    SciTech Connect (OSTI)

    Finger, J.T.; Jacobson, R.D.

    1990-12-01T23:59:59.000Z

    This report describes the Phase 1 drilling operations for the Magma Energy Exploratory Well near Mammoth Lakes, California. An important part of the Department of Energy's Magma Energy Program, this well is designed to reach an ultimate depth of 20,000 feet or a bottomhole temperature of 500{degree}C, whichever comes first. There will be four drilling phases, at least a year apart, with scientific investigations in the borehole between the drilling intervals. Phase 1 of this project resulted in a 20 inch cased hole to 2558 feet, with 185 feet of coring beyond that. This document comprises a narrative of the daily activities, copies of the daily mud and lithologic reports, time breakdowns of rig activities, inventories of lost circulation materials, temperature logs of the cored hole, and a strip chart mud log. 2 figs.

  3. IFE chamber technology testing program in NIF and chamber development test plan

    SciTech Connect (OSTI)

    Abdou, M.A. [Univ. of California, Los Angeles, CA (United States)

    1995-12-31T23:59:59.000Z

    Issues concerning chamber technology testing program in NIF involving: criteria for evaluation/prioritization of experiments, engineering scaling requirements for test article design and material selection and R and D plan prior to NIF testing were addressed in this paper. In order to maximize the benefits of testing program in NIF, the testing in NIF should provide the experimental data relevant to DEMO design choice or to DEMO design predictive capability by utilizing engineering scaling test article designs. Test plans were developed for 2 promising chamber design concepts. Early testing in non-fusion/non-ignition prior to testing in ignition facility serves a critical role in chamber R and D test plans in order to reduce the risks and costs of the more complex experiments in NIF.

  4. Ra-Th disequilibria: Timescale of carbonatite magma formation at Oldoinyo Lengai volcano, Tanzania

    SciTech Connect (OSTI)

    Williams, R.W.; Gill, J.B.; Bruland, K.W. (Univ. of California, Santa Cruz (USA))

    1988-04-01T23:59:59.000Z

    This paper discusses geologic models dealing with the formation of carbonatites from recent lavas of the Oldoninyo Lengai volcano, Tanzania. This paper also acts as a rebutal to an earlier writing which discussed potential flaws in the collection and dating of the carbonatites. The paper goes on to provide activity ratios from different carbonatites and discussion the lack of evidence for fractional crystallization in a olivine sovite magma.

  5. Experimental Constraints on the Deep Magma Feeding System at Stromboli Volcano, Italy

    E-Print Network [OSTI]

    Boyer, Edmond

    magmas at their storage level and discuss their petro- genesis. Fluid-present, H2O- and CO2-bearing, near analyzed by Fourier transform IR spectroscopy and their H2O and CO2 concentrations compared with those balance. They range from CO2-rich (XH2O $ 0Á2) at 400 MPa to H2O-rich (XH2O $ 0Á8) at 100 MPa.The free

  6. Comparative assessment of five potential sites for hydrothermal-magma systems: energy transport

    SciTech Connect (OSTI)

    Hardee, H.C.

    1980-09-01T23:59:59.000Z

    A comparative assessment of five sites is being prepared as part of a Continental Scientific Drilling Program (CSDP) review of thermal regimes for the purpose of scoping areas for future research and drilling activities. This background report: discusses the various energy transport processes likely to be encountered in a hydrothermal-magma system, reviews related literature, discusses research and field data needs, and reviews the sites from an energy transport viewpoint. At least three major zones exist in the magma-hydrothermal transport system: the magma zone, the hydrothermal zone, and the transition zone between the two. Major energy transport questions relate to the nature and existence of these zones and their evolution with time. Additional energy transport questions are concerned with the possible existence of critical state and super-critical state permeable convection in deep geothermal systems. A review of thermal transport models emphasizes the fact that present transport models and computational techniques far outweigh the scarcity and quality of deep field data.

  7. A spark chamber for cosmic ray research 

    E-Print Network [OSTI]

    Jelinek, Al Vincent

    1964-01-01T23:59:59.000Z

    chambez *re r- -e evenis, anc to obtain good sta- s s ical data with the prese. . i sysiezz wou'8 require t! e exarina- iion o" severs' '. '. ous" no. pictures. ne effic ency zoz two simu ianeous particles in argon oius alcohol vspour is e timasec.... to be 75I15~ji. The effic ency of the . con-he' ium and the helium-alcohol vapour zillings are 1 igner about 85- 5(i. 3. Spurious Sparking Spurious sparks in the chamber can be attributed to a num- ber of factors. The most probable cause is ions left...

  8. The Monitored Drift Tube Chambers of Atlas

    SciTech Connect (OSTI)

    Ventura, S. [INFN - Laboratori Nazionali di Frascati (Italy)

    2005-10-12T23:59:59.000Z

    The Atlas experiment has been designed to explore the high energy physics frontier at the TeV energy scale and to investigate on the physics of the Standard Model and beyond at the Large Hadron Collider (LHC) at Cern. The Muon Spectrometer represents the most part of the Atlas detector. It has been designed to provide standalone measurement of the transverse muon momenta with a relative accuracy of 3% over a wide momentum range up to 10% for momenta of 1 TeV. This high accuracy is provided by the Monitored Drift-Tube chambers (MDT) which can determine the track trajectory with a precision of 40 {mu}m.

  9. COMPUTED TOMOGRAPHIC RECONSTRUCTION OF BEAM PROFILES WITH A MULTI-WIRE CHAMBER

    E-Print Network [OSTI]

    Alonso, J.R.

    2010-01-01T23:59:59.000Z

    the beam with a small ion chamber. Both of these techniquesstudies of the chamber. A for heav;' ion radiotherapy beam

  10. axial blanket experiments: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and ideas. We concentrate on the explanation and illustration of the key concept of bucket: its definition, formation and how it is used in generating the axial map. Keywords:...

  11. axial flux machine: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and ideas. We concentrate on the explanation and illustration of the key concept of bucket: its definition, formation and how it is used in generating the axial map. Keywords:...

  12. axial turbine cascade: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and ideas. We concentrate on the explanation and illustration of the key concept of bucket: its definition, formation and how it is used in generating the axial map. Keywords:...

  13. Secondary air interaction with main flow in axial turbines

    E-Print Network [OSTI]

    Zlatinov, Metodi B. (Metodi Blagoev)

    2011-01-01T23:59:59.000Z

    Secondary air, known as purge air, is injected through seals in the hub and shroud of axial turbines to prevent hot gas ingestion into the endwall cavities. An investigation into the interaction of purge ow with turbine ...

  14. The axial behaviour of piled foundations in liquefiable soil

    E-Print Network [OSTI]

    Stringer, Mark

    2012-07-03T23:59:59.000Z

    Understanding the mechanisms by which any engineering structure resists load is an essential requirement for its consistent and reliable design. The axial resistance which can be mobilised by piled foundations in liquefiable soils when subjected...

  15. Applications of axial and radial compressor dynamic system modeling

    E-Print Network [OSTI]

    Spakovszky, Zoltán S. (Zoltán Sándor), 1972-

    2001-01-01T23:59:59.000Z

    The presented work is a compilation of four different projects related to axial and centrifugal compression systems. The projects are related by the underlying dynamic system modeling approach that is common in all of them. ...

  16. axial flow pump: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and Information Sciences Websites Summary: of a configuration that includes an axial pump and a bundle of tubes that mimics the cool source of a heat exchangerEXPERIMENTAL AND...

  17. Optimization of the axial power shape in pressurized water reactors

    E-Print Network [OSTI]

    Melik, M. A.

    1981-01-01T23:59:59.000Z

    Analytical and numerical methods have been applied to find the optimum axial power profile in a PWR with respect to uranium utilization. The preferred shape was found to have a large central region of uniform power density, ...

  18. Axial clad strain behavior of sphere-pac fuel pins 

    E-Print Network [OSTI]

    Thomas, James Kelly

    1986-01-01T23:59:59.000Z

    quantitative di f f er ences exist. 17 CHAPTER III STEADY STATE MODELING Introduction This section descr ibes the analytic model developed to predict the axial shear load bearing capacity of a packed particle bed. The goal of this model development... par ticle beds. 36 CHAPTER IV VIBRATIONAL EXPERIMENTS Introduction The model developed in the previous chapter provides a method to predict the axial shear load bearing capacity of a packed particle bed under negligible vibr ation conditions...

  19. A wave refraction analysis for an axially symmetrical island

    E-Print Network [OSTI]

    Forst, Ronald John

    1966-01-01T23:59:59.000Z

    A WAVE REFRACTION ANALYSIS FOR AN AXIALLY SYMMETRICAL ISLAND A Thesis By LIEUTENANT RONALD J FORST UNITED STATES NAVY Submitted to the Graduate College of the Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE l966 Major Subject Oceanography A WAVE REFRACTION ANALYSIS FOR AN AXIALLY SYMMETRICAL ISLAND A Thesis By LIEUTENANT RONALD J FORST UNITED STATES NAVY Approved as to style and content by; ( airma Committee) Head of Dep rtme t...

  20. Design of high temperature high speed electromagnetic axial thrust bearing

    E-Print Network [OSTI]

    Mohiuddin, Mohammad Waqar

    2002-01-01T23:59:59.000Z

    DESIGN OF HIGH TEMPERATURE HIGH SPEED ELECTROMAGNETIC AXIAL THRUST BEARING A Thesis by MOHAMMAD WAQAR MOHIUDDIN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 2002 Major Subject: Mechanical Engineering DESIGN OF HIGH TEMPERATURE HIGH SPEED ELECTROMAGNETIC AXIAL THRUST BEARING A Thesis by MOHAMMAD WAQAR MOHIUDDIN Submitted to Texas A&M University in partial fulfillment...

  1. Superfluid Phase Stability of 3 He in Axially Anisotropic Aerogel

    E-Print Network [OSTI]

    J. Pollanen; J. P. Davis; B. Reddy; K. R. Shirer; H. Choi

    Abstract. Measurements of superfluid 3 He in 98 % aerogel demonstrate the existence of a metastable A-like phase and a stable B-like phase. It has been suggested that the relative stability of these two phases is controlled by anisotropic quasiparticle scattering in the aerogel. Anisotropic scattering produced by axial compression of the aerogel has been predicted to stabilize the axial state of superfluid 3 He. To explore this possiblity, we used transverse acoustic impedance to map out the phase diagram of superfluid 3 He in a ? 98 % porous silica aerogel subjected to 17 % axial compression. We have previously shown that axial anisotropy in aerogel leads to optical birefringence and that optical cross-polarization studies can be used to characterize such anisotropy. Consequently, we have performed optical cross-polarization experiments to verify the presence and uniformity of the axial anisotropy in our aerogel sample. We find that uniform axial anisotropy introduced by 17 % compression does not stabilize the A-like phase. We also find an increase in the supercooling of the A-like phase at lower pressure, indicating a modification to B-like phase nucleation in globally anisotropic aerogels. 1.

  2. Optical Alignment System for the PHENIX Muon Tracking Chambers

    E-Print Network [OSTI]

    J. Murata; A. Al-Jamel; R. L. Armendariz; M. L. Brooks; T. Horaguchi; N. Kamihara; H. Kobayashi; D. M. Lee; T. -A. Shibata; W. E. Sondheim

    2002-12-26T23:59:59.000Z

    A micron-precision optical alignment system (OASys) for the PHENIX muon tracking chambers is developed. To ensure the required mass resolution of vector meson detection, the relative alignment between three tracking station chambers must be monitored with a precision of 25$\\mu$m. The OASys is a straightness monitoring system comprised of a light source, lens and CCD camera, used for determining the initial placement as well as for monitoring the time dependent movement of the chambers on a micron scale.

  3. Dielectric liquid ionization chambers for detecting fast neutrons

    E-Print Network [OSTI]

    Boyd, Erin M

    2008-01-01T23:59:59.000Z

    Three ionization chambers with different geometries have been constructed and filled with dielectric liquids for detection of fast neutrons. The three dielectric liquids studied were Tetramethylsilane (TMS), Tetramethylpentane ...

  4. air wall ionization chambers: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of California eScholarship Repository Summary: chamber, passive sampling, passive solar house, measurementhouse, we planed the distribution of fresh air, passivepassive...

  5. The hydrogen bubble chamber and the strange resonances

    SciTech Connect (OSTI)

    Alvarez, L.W.

    1985-06-01T23:59:59.000Z

    The author's recollections of his experience in the use of bubble chambers and the discoveries of strange resonances are given. (LEW)

  6. Impact of axial diffusion on nitric oxide exchange in the lungs

    E-Print Network [OSTI]

    George, Steven C.

    Impact of axial diffusion on nitric oxide exchange in the lungs HYE-WON SHIN1 AND STEVEN C. GEORGE1, Hye-Won, and Steven C. George. Impact of axial diffusion on nitric oxide exchange in the lungs. J Appl of the lungs, but neglects axial diffusion. We incorporated axial diffusion into a one-dimensional trumpet

  7. Comparative assessment of five potential sites for hydrothermal magma systems: geochemistry

    SciTech Connect (OSTI)

    White, A.F.

    1980-08-01T23:59:59.000Z

    A brief discussion is given of the geochemical objectives and questions that must be addressed in such an evaluation. A summary of the currently published literature that is pertinent in answering these questions is presented for each of the five areas: The Geysers-Clear Lake region, Long Valley, Rio Grand Rift, Roosevelt Hot Springs, and the Salton Trough. The major geochemical processes associated with proposed hydrothermal sites are categorized into three groups for presentation: geochemistry of magma and associated volcanic rocks, geochemistry of hydrothermal solutions, and geochemistry of hydrothermal alteration. (MHR)

  8. Exciting Internship at the American Arab Chamber of Commerce

    E-Print Network [OSTI]

    Cinabro, David

    Exciting Internship at the American Arab Chamber of Commerce Take advantage of the opportunity@americanarab.com with the subject "Internship Opportunity." Include a brief statement on why you would like to work at the American Arab Chamber of Commerce, along with your availability. If you are looking for an internship to fulfill

  9. aerosol test chamber: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    aerosol test chamber First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 IFE Chamber Technology Testing...

  10. Axial Current Generation from Electric Field: Chiral Electric Separation Effect

    E-Print Network [OSTI]

    Xu-Guang Huang; Jinfeng Liao

    2013-06-07T23:59:59.000Z

    We study a relativistic plasma containing charged chiral fermions in an external electric field. We show that with the presence of both vector and axial charge densities, the electric field can induce an axial current along its direction and thus cause chirality separation. We call it the Chiral Electric Separation Effect (CESE). On very general basis, we argue that the strength of CESE is proportional to $\\mu_V\\mu_A$ with $\\mu_V$ and $\\mu_A$ the chemical potentials for vector charge and axial charge. We then explicitly calculate this CESE conductivity coefficient in thermal QED at leading-log order. The CESE can manifest a new gapless wave mode propagating along the electric field. Potential observable of CESE in heavy-ion collisions is also discussed.

  11. Axial Current Generation from Electric Field: Chiral Electric Separation Effect

    E-Print Network [OSTI]

    Huang, Xu-Guang

    2013-01-01T23:59:59.000Z

    We study a relativistic plasma containing charged chiral fermions in an external electric field. We show that with the presence of both vector and axial charge densities, the electric field can induce an axial current along its direction and thus cause chirality separation. We call it the Chiral Electric Separation Effect (CESE). On very general basis, we argue that the strength of CESE is proportional to $\\mu_V\\mu_A$ with $\\mu_V$ and $\\mu_A$ the chemical potentials for vector charge and axial charge. We then explicitly calculate this CESE conductivity coefficient in thermal QED at leading-log order. The CESE can manifest a new gapless wave mode propagating along the electric field. Potential observable of CESE in heavy-ion collisions is also discussed.

  12. An investigation of axial-flow compressor blade treatments

    E-Print Network [OSTI]

    Sangerhausen, Charles Roger

    1974-01-01T23:59:59.000Z

    of axial-flow compressor [5] . According to Schlicting [1], the basic methods of controlling the boundary layer on a body are (1) relative motion of the body surface w1th the flow, (2) acceleration of the boundary layer by blowing, (3) suction, (0) in...c methods. The literature survey revealed that three d1fferent techn1ques of boundary layer oontrol have been investigated for applicat1on to axial- flow compressor bladingi these are (1) the slotted blade, (2) the blade shape designed for a...

  13. EFFECTS OF CHAMBER GEOMETRY AND GAS PROPERTIES ON HYDRODYNAMIC EVOLUTION OF IFE Zoran Dragojlovic1

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    -rays and ions travel through the chamber and deposit some of their energy in the chamber background gas; the effects of various heat sources and transfer mechanisms such as photon and ion heat deposition and chamberEFFECTS OF CHAMBER GEOMETRY AND GAS PROPERTIES ON HYDRODYNAMIC EVOLUTION OF IFE CHAMBERS Zoran

  14. Vacuum chamber for ion manipulation device

    DOE Patents [OSTI]

    Chen, Tsung-Chi; Tang, Keqi; Ibrahim, Yehia M; Smith, Richard D; Anderson, Gordon A; Baker, Erin M

    2014-12-09T23:59:59.000Z

    An ion manipulation method and device is disclosed. The device includes a pair of substantially parallel surfaces. An array of inner electrodes is contained within, and extends substantially along the length of, each parallel surface. The device includes a first outer array of electrodes and a second outer array of electrodes. Each outer array of electrodes is positioned on either side of the inner electrodes, and is contained within and extends substantially along the length of each parallel surface. A DC voltage is applied to the first and second outer array of electrodes. A RF voltage, with a superimposed electric field, is applied to the inner electrodes by applying the DC voltages to each electrode. Ions either move between the parallel surfaces within an ion confinement area or along paths in the direction of the electric field, or can be trapped in the ion confinement area. A predetermined number of pairs of surfaces are disposed in one or more chambers, forming a multiple-layer ion mobility cyclotron device.

  15. May 31-June 1, 2001 A. R. Raffray, et al., Assessment of Dry Chamber Walls as Preliminary Step in Defining Key Processes for Chamber Clearing Code 1

    E-Print Network [OSTI]

    Raffray, A. René

    in Defining Key Processes for Chamber Clearing Code 6 Photon and Ion Attenuations in Carbon and Tungsten #12May 31-June 1, 2001 A. R. Raffray, et al., Assessment of Dry Chamber Walls as Preliminary Step in Defining Key Processes for Chamber Clearing Code 1 Assessment of Dry Chamber Wall Configurations

  16. Neutrino Physics and Nuclear Axial Two-Body Interactions

    E-Print Network [OSTI]

    A. B. Balantekin; H. Yuksel

    2004-11-06T23:59:59.000Z

    We consider the counter-term describing isoscalar axial two-body currents in the nucleon-nucleon interaction, L1A, in the effective field theory approach. We determine this quantity using the solar neutrino data. We investigate the variation of L1A when different sets of data are used.

  17. Proceedings of the Axial Offset Anomaly (AOA) Science Workshop

    SciTech Connect (OSTI)

    None

    2003-06-01T23:59:59.000Z

    This report presents proceedings of the Axial Offset Anomaly (AOA) Science Workshop, held February 10-11 in Palo Alto, California. Twenty-two papers were presented on various aspects of AOA by utilities, EPRI Robust Fuel Program contractors, staff from EPRI and universities, international researchers, and equipment vendors.

  18. Collective quantization of axially symmetric gravitating B=2 skyrmion

    E-Print Network [OSTI]

    Hisayuki Sato; Nobuyuki Sawado; Noriko Shiiki

    2007-01-05T23:59:59.000Z

    In this paper we perform collective quantization of an axially symmetric skyrmion with baryon number two.The rotational and isorotational modes are quantized to obtain the static properties of a deuteron and other dibaryonic objects such as masses, charge densities, magnetic moments. We discuss how the gravity affects to those observables.

  19. Small core axial compressors for high efficiency jet aircraft

    E-Print Network [OSTI]

    DiOrio, Austin Graf

    2012-01-01T23:59:59.000Z

    This thesis quantifies mechanisms that limit efficiency in small core axial compressors, defined here as compressor exit corrected flow between 1.5 and 3.0 lbm/s. The first part of the thesis describes why a small engine ...

  20. The deep structure of Axial Volcano Michael West

    E-Print Network [OSTI]

    West, Michael

    the competing roles or ocean ridge and hot spot at Axial Volcano Provide a template on which long-term studies;Airgun survey April '99 20 gun array 8670 in3 volume 8 days #12;Airgun survey, April '99 5000+ shots 1225

  1. Operational benefits of relaxed axial power distribution control limits

    SciTech Connect (OSTI)

    Kitlan, M.S. Jr.; Miller, R.W.

    1987-01-01T23:59:59.000Z

    Constant axial offset control (CAOC) was developed in the early 1970s in response to lower loss-of-coolant accident-based peaking factor limits. Th CAOC requires control of the axial power distribution within a specified band, typically +/- 5% or +3, -12% axial flux difference (AFD), about a measured target value of AFD. Operational outside of the CAOC limits results in the accumulation of penalty time. One hour of penalty time in any 24-h period is permitted. Although CAOC is sufficient to ensure peaking factor limits are satisfied, operation outside of CAOC limits is beneficial under certain conditions. Allowing a relaxation in CAOC restrictions can be used both to enhance the load follow capability of the plant by allowing control strategies that minimize the boron system duty or increase the return to power capability and to greatly increase the ability to return to power after a plant trip or shutdown. To achieve these benefits, relaxed axial offset control (RAOC) was developed. Other benefits of RAOC include a simplified technical specification and the ability to perform in-core/ex-core calibrations at higher powers. Duke Power Company has benefited in many of these ways by changing from CAOC power distribution limits to RAOC power distribution limits at the McGuire Nuclear Station. One of the chief benefits has been the ability to achieve full power much more quickly following shutdowns of short duration and reactor trips during the last half of the cycle lifetime.

  2. ELECTROMECHANICAL RELIABILITY TESTING OF THREE-AXIAL SILICON FORCE SENSORS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , available automatic test equipment for integrated circuits (ICs) can be leveraged [2]. The reliabilityELECTROMECHANICAL RELIABILITY TESTING OF THREE-AXIAL SILICON FORCE SENSORS S. Spinner1,2, J the measurement results. 1. INTRODUCTION The reliability of microelectromechanical systems (MEMS) receives growing

  3. axial fuel optimization: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    axial fuel optimization First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Trajectory optimization for...

  4. Turbine component cooling channel mesh with intersection chambers

    DOE Patents [OSTI]

    Lee, Ching-Pang; Marra, John J

    2014-05-06T23:59:59.000Z

    A mesh (35) of cooling channels (35A, 35B) with an array of cooling channel intersections (42) in a wall (21, 22) of a turbine component. A mixing chamber (42A-C) at each intersection is wider (W1, W2)) than a width (W) of each of the cooling channels connected to the mixing chamber. The mixing chamber promotes swirl, and slows the coolant for more efficient and uniform cooling. A series of cooling meshes (M1, M2) may be separated by mixing manifolds (44), which may have film cooling holes (46) and/or coolant refresher holes (48).

  5. IMAGING WITH A MULTIPLANE MULTIWIRE PROPORTIONAL CHAMBER USING HEAVY ION BEAMS

    E-Print Network [OSTI]

    Chu, W.T.

    2010-01-01T23:59:59.000Z

    1. When the he^vy ions penetrate the chamber, the resultingMULTIWIRE PROPORTIONAL CHAMBER USING HEAVY-ION BEAMS* U. T.Ion Beam Studies and Imaging with a Nultiplane Multiwire Proportional Chamber,"

  6. The Low-18O Late-Stage Ferrodiorite Magmas in the Skaergaard Intrusion: Result of Liquid Immiscibility, Thermal Metamorphism, or

    E-Print Network [OSTI]

    Bindeman, Ilya N.

    , Eugene, Oregon 97403, U.S.A. (e-mail: bindeman@uoregon.edu) A B S T R A C T We report new laser fluorination oxygen isotope analyses of selected samples throughout the Skaergaard intrusion in East Greenland of a higher-18 O, higher-SiO2 granophyric melt, thereby depleting the residual Fe-rich ferrodiorite magma

  7. ELSEVIER Earth and Planetary Science Letters 143( 1996)8l-94 Petrological models of magma evolution and deep crustal

    E-Print Network [OSTI]

    Farnetani, Cinzia G.

    EPSL ELSEVIER Earth and Planetary Science Letters 143( 1996)8l-94 Petrological models of magma. We use the petrological code MELTS [I] to quantify the evolution of primary mantle melts) our petrological model predicts a distinct crustal structure: at the base of the crust (e.g., at P = 3

  8. Environmental chamber studies of atmospheric reactivities of volatile organic compounds: Effects of varying chamber and light source

    SciTech Connect (OSTI)

    Carter, W.; Luo, D.; Malkina, I.; Pierce, J. [California Univ., Riverside, CA (United States)

    1995-05-01T23:59:59.000Z

    Photochemical oxidant models are essential tools for assessing effects of emissions changes on ground-level ozone formation. Such models are needed for predicting the ozone impacts of increased alternative fuel use. The gas-phase photochemical mechanism is an important component of these models because ozone is not emitted directly, but is formed from the gas-phase photochemical reactions of the emitted volatile organic compounds (VOCs) and oxides of nitrogen (NO{sub x}) in air. The chemistry of ground level ozone formation is complex; hundreds of types of VOCs being emitted into the atmosphere, and most of their atmospheric reactions are not completely understood. Because of this, no chemical model can be relied upon to give even approximately accurate predictions unless it has been evaluated by comparing its predictions with experimental data. Therefore an experimental and modeling study was conducted to assess how chemical mechanism evaluations using environmental chamber data are affected by the light source and other chamber characteristics. Xenon arc lights appear to give the best artificial representation of sunlight currently available, and experiments were conducted in a new Teflon chamber constructed using such a light source. Experiments were also conducted in an outdoor Teflon Chamber using new procedures to improve the light characterization, and in Teflon chambers using blacklights. These results, and results of previous runs other chambers, were compared with model predictions using an updated detailed chemical mechanism. The magnitude of the chamber radical source assumed when modeling the previous runs were found to be too high; this has implications in previous mechanism evaluations. Temperature dependencies of chamber effects can explain temperature dependencies in chamber experiments when Ta-300{degree}K, but not at temperatures below that.

  9. Molecular-Level Study of the Effect of Prior Axial Compression/Torsion on the Axial-Tensile Strength

    E-Print Network [OSTI]

    Grujicic, Mica

    that prior axial torsion can induce major changes in the material microstructure, causing significant, such as bullets, detonated-mine-induced soil ejecta, improvised explosive devices (IEDs), shell or turbine frag of high-fidelity material-constitutive models capa- ble of describing the behavior of fibers

  10. November 8-9, 2005 Blanket Design for Large Chamber

    E-Print Network [OSTI]

    Raffray, A. René

    - Max. FS/Li interface temp. ODS Advanced Case Advanced Case RAFS RAFS ODS FS ODS FS Chamber radius, Rchamb (m) 10.5 10.5 11 11 Rep rate 5

  11. Neutral Gas Expansion in a Cylindrical Helicon Discharge Chamber

    E-Print Network [OSTI]

    Walker, Mitchell

    ­1500 G) magnetic field parallel to the axis of the tube. In many helicon experiments for basic plasma research, the discharge chamber is composed of a small diameter (2­10 cm), relatively long (0.5­1.75 m

  12. atlas muon chamber: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    detectors and a calibrated BF3 neutron detector provided monitoring of the neutron flux-density and energy. The sensitivity of the drift chamber to the neutrons was measured...

  13. atlas mdt chambers: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    detectors and a calibrated BF3 neutron detector provided monitoring of the neutron flux-density and energy. The sensitivity of the drift chamber to the neutrons was measured...

  14. atlas muon chambers: Topics by E-print Network

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    detectors and a calibrated BF3 neutron detector provided monitoring of the neutron flux-density and energy. The sensitivity of the drift chamber to the neutrons was measured...

  15. Carrying Semiautomatic Pistols with a Round in the Chamber

    Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

    1999-10-28T23:59:59.000Z

    Sets forth requirements for a DOE security police officer who must carry a round in the chamber of a semiautomatic pistol while on duty. Does not cancel other directives.

  16. Development of the Captive Aerosol Growth and Evolution Chamber System

    E-Print Network [OSTI]

    Antonietti, Carlos G

    2014-08-28T23:59:59.000Z

    The Captive Aerosol Growth and Evolution (CAGE) Chamber System is an tool designed to study the evolution of aerosols under conditions identical or similar to those of the surrounding environment. Our motivation was to quantify the sensitivity...

  17. A self-triggered readout for a time projection chamber

    E-Print Network [OSTI]

    Werner, Andrew Thompson, 1981-

    2004-01-01T23:59:59.000Z

    A self-triggering readout for a time projection chamber (TPC) is presented, with applications to novel forms of data acquisition for high energy physics application. The construction and initial testing of the readout ...

  18. E-Cloud Build-up in Grooved Chambers

    E-Print Network [OSTI]

    Venturini, Marco

    2007-01-01T23:59:59.000Z

    and F. Zimmermann, ”LC e-Cloud Activities at CERN”, talkal. , Simulations of the Electron Cloud for Vari- ous Con?E-CLOUD BUILD-UP IN GROOVED CHAMBERS ? M. Venturini † LBNL,

  19. Chamber technology concepts for inertial fusion energy: Three recent examples

    SciTech Connect (OSTI)

    Meier, W.R.; Moir, R.W. [Lawrence Livermore National Lab., CA (United States); Abdou, M.A. [California Univ., Los Angeles, CA (United States)

    1997-02-27T23:59:59.000Z

    The most serious challenges in the design of chambers for inertial fusion energy (IFE) are 1) protecting the first wall from fusion energy pulses on the order of several hundred megajoules released in the form of x rays, target debris, and high energy neutrons, and 2) operating the chamber at a pulse repetition rate of 5-10 Hz (i.e., re-establishing, the wall protection and chamber conditions needed for beam propagation to the target between pulses). In meeting these challenges, designers have capitalized on the ability to separate the fusion burn physics from the geometry and environment of the fusion chamber. Most recent conceptual designs use gases or flowing liquids inside the chamber. Thin liquid layers of molten salt or metal and low pressure, high-Z gases can protect the first wall from x rays and target debris, while thick liquid layers have the added benefit of protecting structures from fusion neutrons thereby significantly reducing the radiation damage and activation. The use of thick liquid walls is predicted to 1) reduce the cost of electricity by avoiding the cost and down time of changing damaged structures, and 2) reduce the cost of development by avoiding the cost of developing a new, low-activation material. Various schemes have been proposed to assure chamber clearing and renewal of the protective features at the required pulse rate. Representative chamber concepts are described, and key technical feasibility issues are identified for each class of chamber. Experimental activities (past, current, and proposed) to address these issues and technology research and development needs are discussed.

  20. Laser calibration system for the CERES Time Projection Chamber

    E-Print Network [OSTI]

    Dariusz Miskowiec; Peter Braun-Munzinger

    2008-02-15T23:59:59.000Z

    A Nd:YAG laser was used to simulate charged particle tracks at known positions in the CERES Time Projection Chamber at the CERN SPS. The system was primarily developed to study the response of the readout electronics and to calibrate the electron drift velocity. Further applications were the determination of the gating grid transparency, the chamber position calibration, and long-term monitoring of drift properties of the gas in the detector.

  1. Modeling of FRP-jacketed RC columns subject to combined axial and lateral loads

    E-Print Network [OSTI]

    Lee, Chung-Sheng

    2006-01-01T23:59:59.000Z

    LOCATIONS #6 u-bars @ 4" 3" PVC for axial load and verticalsteel Steel jacket encasing load stub 2" PVC for clevisattatch 3" PVC for axial load A B Vertical tiedown Column

  2. European Fusion Theory Conference Non-local features of transport in the axial tokamak region

    E-Print Network [OSTI]

    9th European Fusion Theory Conference Non-local features of transport in the axial tokamak region J effects in the axial region of an axi- symmetric tokamak equilibrium. The starting point is the guiding

  3. Effect of circumferential groove casing treatment parameters on axial compressor flow range

    E-Print Network [OSTI]

    Hanley, Brian K. (Brian Kyle)

    2010-01-01T23:59:59.000Z

    The impact on compressor flow range of circumferential casing grooves of varying groove depth, groove axial location, and groove axial extent is assessed against that of a smooth casing wall using computational experiments. ...

  4. A Comparative Study of Modular Axial Flux Podded Generators for Marine Current Turbines

    E-Print Network [OSTI]

    Brest, Université de

    A Comparative Study of Modular Axial Flux Podded Generators for Marine Current Turbines Sofiane turbines (MCTs). Due to the submarine environment, maintenance operations are very hard, very costly current turbine, axial flux permanent magnet generator, design, optimization. Nomenclature MCT = Marine

  5. Volcanism, Structure, and Geochronology of Long Valley Caldera...

    Open Energy Info (EERE)

    chemically zoned magma chamber. Holocene rhyolitic and phreatic eruptions suggest that residual magma was present in the chamber as recently as 450 yr ago. Intracaldera...

  6. Eigenmodes in Two Simplified Chamber Structures Studied for Spurious Microwaves in the APS Storage Ring Beam Chamber

    E-Print Network [OSTI]

    Kemner, Ken

    calculate the transverse electric field Ey at two points BPM+ and BPM - shown in Figures 2 and 3 the transverse electric field Ey at two points BPM+ and BPM - in the simplified chamber structure with a short

  7. Correction to "Threedimensional computational axial tomography scan of a volcano with cosmic ray muon radiography"

    E-Print Network [OSTI]

    Aoki, Yosuke

    Correction to "Threedimensional computational axial tomography scan of a volcano with cosmic ray.1029/2011JB008256. [1] In the paper "Threedimensional computational axial tomography scan of a volcano. Aoki, R. Nishiyama, D. Shoji, and H. Tsuiji (2011), Correction to "Threedimensional computational axial

  8. AXIAL-FIELD SYNCHRONOUS MACHINE WITH HOMOPOLAR FLUX IN THE AIRGAP FOR A FLYWHEEL ACCUMULATOR

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    AXIAL-FIELD SYNCHRONOUS MACHINE WITH HOMOPOLAR FLUX IN THE AIRGAP FOR A FLYWHEEL ACCUMULATOR@bretagne.ens-cachan.fr Abstract: A new axial-field synchronous machine designed for a flywheel accumulator is presented herein with experimental results. Keywords: flywheel accumulator, axial-field synchronous machine, double-face printed

  9. Axially staged combustion system for a gas turbine engine

    DOE Patents [OSTI]

    Bland, Robert J. (Oviedo, FL)

    2009-12-15T23:59:59.000Z

    An axially staged combustion system is provided for a gas turbine engine comprising a main body structure having a plurality of first and second injectors. First structure provides fuel to at least one of the first injectors. The fuel provided to the one first injector is adapted to mix with air and ignite to produce a flame such that the flame associated with the one first injector defines a flame front having an average length when measured from a reference surface of the main body structure. Each of the second injectors comprising a section extending from the reference surface of the main body structure through the flame front and having a length greater than the average length of the flame front. Second structure provides fuel to at least one of the second injectors. The fuel passes through the one second injector and exits the one second injector at a location axially spaced from the flame front.

  10. Axial SiGe Heteronanowire Tunneling Field-Effect Transistors

    SciTech Connect (OSTI)

    Le, Son T.; Jannaty, P.; Luo, Xu; Zaslavsky, A.; Perea, Daniel E.; Dayeh, Shadi A.; Picraux, Samuel T.

    2012-10-31T23:59:59.000Z

    We present silicon-compatible tri-gated p-Ge/i-Si/n-Si axial heteronanowire tunneling field-effect transistors (TFETs), where on-state tunneling occurs in the Ge drain section, while off-state leakage is dominated by the Si junction in the source. Our TFETs have high ION ~ 2 µA/µm, fully suppressed ambipolarity, and a sub-threshold slope SS ~ 140 mV/decade over 4 decades of current with lowest SS ~ 50 mV/decade. Device operation in the tunneling mode is confirmed by three-dimensional TCAD simulation. Interestingly, in addition to the TFET mode, our devices work as standard nanowire FETs with good ION/IOFF ratio when the source-drain junction is forward-biased. The improved transport in both biasing modes confirms the benefits of utilizing bandgap engineered axial nanowires for enhancing device performance.

  11. Numerical analysis of a microwave torch with axial gas injection

    SciTech Connect (OSTI)

    Gritsinin, S. I.; Davydov, A. M.; Kossyi, I. A., E-mail: kossyi@fpl.gpi.ru [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Kulumbaev, E. B. [National Research University Belgorod State University (Russian Federation)] [National Research University Belgorod State University (Russian Federation); Lelevkin, V. M. [Kyrgyz-Russian Slavic University (Kyrgyzstan)] [Kyrgyz-Russian Slavic University (Kyrgyzstan)

    2013-07-15T23:59:59.000Z

    The characteristics of a microwave discharge in an argon jet injected axially into a coaxial channel with a shortened inner electrode are numerically analyzed using a self-consistent equilibrium gas-dynamic model. The specific features of the excitation and maintenance of the microwave discharge are determined, and the dependences of the discharge characteristics on the supplied electromagnetic power and gas flow rate are obtained. The calculated results are compared with experimental data.

  12. Measurement of axial injection displacement with trim coil current unbalance

    SciTech Connect (OSTI)

    Covo, Michel Kireeff, E-mail: mkireeffcovo@lbl.gov [Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720 (United States)

    2014-08-15T23:59:59.000Z

    The Dee probe used for measuring internal radial beam intensity shows large losses inside the radius of 20 cm of the 88 in. cyclotron. The current of the top and bottom innermost trim coil 1 is unbalanced to study effects of the axial injection displacement. A beam profile monitor images the ion beam bunches, turn by turn. The experimental bunch center of mass position is compared with calculations of the magnetic mirror effect displacement and shows good agreement.

  13. Coral Extension Rate Analysis Using Computed Axial Tomography

    E-Print Network [OSTI]

    Yudelman, Eleanor Ann

    2014-01-10T23:59:59.000Z

    CORAL EXTENSION RATE ANALYSIS USING COMPUTED AXIAL TOMOGRAPHY A Thesis by ELEANOR ANN YUDELMAN Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE Chair of Committee, Niall Slowey Committee Members, Deborah Thomas Benjamin Giese George P. Schmahl Head of Department, Deborah Thomas May 2014 Major Subject: Oceanography Copyright 2014 Eleanor Ann Yudelman ii ABSTRACT...

  14. Enhanced betatron X-rays from axially modulated plasma wakefields

    E-Print Network [OSTI]

    Palastro, J P; Gordon, D

    2015-01-01T23:59:59.000Z

    In the cavitation regime of plasma-based accelerators, a population of high-energy electrons tailing the driver can undergo betatron motion. The motion results in X-ray emission, but the brilliance and photon energy are limited by the electrons' initial transverse coordinate. To overcome this, we exploit parametrically unstable betatron motion in a cavitated, axially modulated plasma. Theory and simulations are presented showing that the unstable oscillations increase both the total X-ray energy and average photon energy.

  15. Nuclear reactor control rod with uniformly changeable axial worth

    SciTech Connect (OSTI)

    Freeman, T.R.

    1987-11-17T23:59:59.000Z

    In combination with a fuel assembly having at least one hollow guide thimble, means to compensate for a reduction in reactivity occurring generally uniformly in a transverse direction and symmetric in the axial direction is described, comprising: (a) a control rod inserted in the guide thimble including (i) an elongated inner cylindrical member having a lower end, (ii) an elongated outer cylindrical member surrounding the inner member and having a lower end with concentrically-arranged lower inner and outer edge portions defined thereon, (iii) each of the members being composed of alternating poison and nonpoison regions, (iv) the inner member being axially movable relative to the outer member, (v) an outwardly projecting ledge adapted to support in a rest relationship the lower end of the outer member; and (b) means for retaining the outer member in a stationary position in the guide thimble while the inner member is movable axially relative thereto to adjust the degree to which the poison regions of the members overlap with the nonpoison regions and thereby change the overall worth of the rod. (c) The retaining means are in a lower portion of the guide thimble and sized to support the lower end of the outer member at its lower outer edge portion. The retaining means have a central hole sized to allow passage of the lower end and ledge of the inner member therethrough.

  16. Axial-vector coupling constants and chiral-symmetry restoration

    SciTech Connect (OSTI)

    Henley, E.M. (Department of Physics FM-15 and Institute for Nuclear Theory HN-12, University of Washington, Seattle, Washington 98195 (United States)); Hwang, W.P. (Department of Physics, National Taiwan University, Taipei, Taiwan 10764 (Taiwan, Province of China)); Kisslinger, L.S. (Department of Physics, Carnegie-Mellon University, Pittsburgh, Pennsylvania 15213 (United States))

    1992-07-01T23:59:59.000Z

    The isovector axial-vector coupling constant {ital g}{sub {ital A}} is determined by using the method of QCD sum rules. A sum rule for ({ital g}{sub {ital A}}{minus}1) is obtained, and it is shown that, with standard values of the quark condensates, {ital g}{sub {ital A}}=1.26{plus minus}0.08. It is also shown that the isovector axial-vector coupling ({ital g}{sub {ital A}}{minus}1)=0 in the limit in which chiral symmetry is restored, and the quark condensate vanishes. A sum rule is also obtained for the isoscalar'' axial-vector coupling constant {ital g}{sub {ital A}}{sup {ital S}}, which is found to be 0.13 if the isovector values of susceptibilities are used. On the other hand, {ital g}{sub {ital A}}{sup {ital S}}={minus}0.68 if the quark condensate is set to zero while {ital g}{sub {ital A}}{sup {ital S}}={minus}1.00 if both the quark and gluon condensates vanish in the event of chiral-symmetry restoration. The values of {ital g}{sub {ital A}} and {ital g}{sub {ital A}}{sup {ital S}} allow us to deduce {Delta}{ital u} and {Delta}{ital d} in the proton.

  17. Dark matter limits froma 15 kg windowless bubble chamber

    SciTech Connect (OSTI)

    Szydagis, Matthew Mark; /Chicago U.

    2010-12-01T23:59:59.000Z

    The COUPP collaboration has successfully used bubble chambers, a technology previously applied only to high-energy physics experiments, as direct dark matter detectors. It has produced the world's most stringent spin-dependent WIMP limits, and increasingly competitive spin-independent limits. These limits were achieved by capitalizing on an intrinsic rejection of the gamma background that all other direct detection experiments must address through high-density shielding and empirically-determined data cuts. The history of COUPP, including its earliest prototypes and latest results, is briefly discussed in this thesis. The feasibility of a new, windowless bubble chamber concept simpler and more inexpensive in design is discussed here as well. The dark matter limits achieved with a 15 kg windowless chamber, larger than any previous COUPP chamber (2 kg, 4 kg), are presented. Evidence of the greater radiopurity of synthetic quartz compared to natural is presented using the data from this 15 kg device, the first chamber to be made from synthetic quartz. The effective reconstruction of the three-dimensional positions of bubbles in a highly distorted optical field, with ninety-degree bottom lighting similar to cloud chamber lighting, is demonstrated. Another innovation described in this thesis is the use of the sound produced by bubbles recorded by an array of piezoelectric sensors as the primary means of bubble detection. In other COUPP chambers, cameras have been used as the primary trigger. Previous work on bubble acoustic signature differentiation using piezos is built upon in order to further demonstrate the ability to discriminate between alpha- and neutron-induced events.

  18. June 17-21, 2007 SOFE07, Albuquerque 1 Conceptual Study of Integrated Chamber Core

    E-Print Network [OSTI]

    Raffray, A. René

    as advanced option to reduce or eliminate ion threat on chamber wall · Chamber core concept based on magnetic target (~24% of the energy is in ions and ~1% in photons), a large chamber (~10.75 m) is required options that would reduce the ion threat spectra on the armor and allow for more compact chambers

  19. LASER IFE DIRECT DRIVE CHAMBER CONCEPTS WITH MAGNETIC INTERVENTION A. R. Raffray1

    E-Print Network [OSTI]

    Raffray, A. René

    is the survival of the chamber wall under the ion threat spectra (representing ~25% of the yield energy). The possibility of steering the ions away from the chamber to specially-designed dump chambers using magnetic to accommodate the ion fluxes in the dump chamber provided the right measures are taken to prevent the liquid

  20. Aug. 8-9, 2006 HAPL meeting, GA Advanced Chamber Concept with Magnetic Intervention

    E-Print Network [OSTI]

    Raffray, A. René

    Aug. 8-9, 2006 HAPL meeting, GA 1 Advanced Chamber Concept with Magnetic Intervention: - Ion Dump and Thermal Response of Dump Plates Estimated for Cone-Shaped Chamber · For example case with ~10%of ion wall chamber to satisfy target and laser requirements ·Separate wetted wall chamber to accommodate ions

  1. High pressure argon ionization chamber systems for the measurement of environmental radiation exposure rates

    E-Print Network [OSTI]

    DeCampo, J A; Raft, P D

    1972-01-01T23:59:59.000Z

    High pressure argon ionization chamber systems for the measurement of environmental radiation exposure rates

  2. Reanalysis of bubble chamber measurements of muon-neutrino induced single pion production

    E-Print Network [OSTI]

    Callum Wilkinson; Philip Rodrigues; Susan Cartwright; Lee Thompson; Kevin McFarland

    2014-11-17T23:59:59.000Z

    There exists a longstanding disagreement between bubble chamber measurements of the single pion production channel $\

  3. Initial Back-to-Back Fission Chamber Testing in ATRC

    SciTech Connect (OSTI)

    Benjamin Chase; Troy Unruh; Joy Rempe

    2014-06-01T23:59:59.000Z

    Development and testing of in-pile, real-time neutron sensors for use in Materials Test Reactor experiments is an ongoing project at Idaho National Laboratory. The Advanced Test Reactor National Scientific User Facility has sponsored a series of projects to evaluate neutron detector options in the Advanced Test Reactor Critical Facility (ATRC). Special hardware was designed and fabricated to enable testing of the detectors in the ATRC. Initial testing of Self-Powered Neutron Detectors and miniature fission chambers produced promising results. Follow-on testing required more experiment hardware to be developed. The follow-on testing used a Back-to-Back fission chamber with the intent to provide calibration data, and a means of measuring spectral indices. As indicated within this document, this is the first time in decades that BTB fission chambers have been used in INL facilities. Results from these fission chamber measurements provide a baseline reference for future measurements with Back-to-Back fission chambers.

  4. Extreme-UV lithography vacuum chamber zone seal

    DOE Patents [OSTI]

    Haney, Steven J. (Tracy, CA); Herron, Donald Joe (Manteca, CA); Klebanoff, Leonard E. (San Ramon, CA); Replogle, William C. (Livermore, CA)

    2003-04-15T23:59:59.000Z

    Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.

  5. Extreme-UV lithography vacuum chamber zone seal

    DOE Patents [OSTI]

    Haney, Steven J. (Tracy, CA); Herron, Donald Joe (Manteca, CA); Klebanoff, Leonard E. (San Ramon, CA); Replogle, William C. (Livermore, CA)

    2003-04-08T23:59:59.000Z

    Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.

  6. Extreme-UV lithography vacuum chamber zone seal

    DOE Patents [OSTI]

    Haney, Steven J. (Tracy, CA); Herron, Donald Joe (Manteca, CA); Klebanoff, Leonard E. (San Ramon, CA); Replogle, William C. (Livermore, CA)

    2001-01-01T23:59:59.000Z

    Control of particle contamination on the reticle and carbon contamination of optical surfaces in photolithography systems can be achieved by the establishment of multiple pressure zones in the photolithography systems. The different zones will enclose the reticle, projection optics, wafer, and other components of system. The system includes a vacuum apparatus that includes: a housing defining a vacuum chamber; one or more metrology trays situated within the vacuum chamber each of which is supported by at least one support member, wherein the tray separates the vacuum chamber into a various compartments that are maintained at different pressures; and conductance seal devices for adjoining the perimeter of each tray to an inner surface of the housing wherein the tray is decoupled from vibrations emanating from the inner surface of the housing.

  7. The PEP-II Lower Pressure HER Vacuum Chamber

    SciTech Connect (OSTI)

    DeBarger, S.; Metcalfe, S.; Seeman, J.; Sullivan, M.; Wienands, U.; Wright, D.; /SLAC

    2006-03-13T23:59:59.000Z

    This new vacuum chamber has been installed from 12 to 21 meters upstream of the BaBar detector in the PEP-II High Energy Ring (HER) to reduce lost particle backgrounds. The backgrounds from HER now dominate the backgrounds in the BaBar detector and the present vacuum pressure is 1 x 10{sup -9} Torr. The new chamber will increase the pumping significantly by adding 18 x 2000 l/s titanium sublimation pumps to the existing 5 x 440 l/s ion pumps, and is expected to reduce the pressure by about a factor of five. Features of the chamber include improved water cooling, improved vacuum conductance through copper RF screens featuring over 15,000 small square holes and the ability to sublimate titanium while the beam is still on.

  8. Chamber Design for the Laser Inertial Fusion Energy (LIFE) Engine

    SciTech Connect (OSTI)

    Latkowski, J F; Abbott, R P; Aceves, S; Anklam, T; Badders, D; Cook, A W; DeMuth, J; Divol, L; El-Dasher, B; Farmer, J C; Flowers, D; Fratoni, M; ONeil, R G; Heltemes, T; Kane, J; Kramer, K J; Kramer, R; Lafuente, A; Loosmore, G A; Morris, K R; Moses, G A; Olson, B; Pantano, C; Reyes, S; Rhodes, M; Roe, K; Sawicki, R; Scott, H; Spaeth, M; Tabak, M; Wilks, S

    2010-11-30T23:59:59.000Z

    The Laser Inertial Fusion Energy (LIFE) concept is being designed to operate as either a pure fusion or hybrid fusion-fission system. The present work focuses on the pure fusion option. A key component of a LIFE engine is the fusion chamber subsystem. It must absorb the fusion energy, produce fusion fuel to replace that burned in previous targets, and enable both target and laser beam transport to the ignition point. The chamber system also must mitigate target emissions, including ions, x-rays and neutrons and reset itself to enable operation at 10-15 Hz. Finally, the chamber must offer a high level of availability, which implies both a reasonable lifetime and the ability to rapidly replace damaged components. An integrated design that meets all of these requirements is described herein.

  9. Coanda injection system for axially staged low emission combustors

    DOE Patents [OSTI]

    Evulet, Andrei Tristan (Clifton Park, NY); Varatharajan, Balachandar (Cincinnati, OH); Kraemer, Gilbert Otto (Greer, SC); ElKady, Ahmed Mostafa (Niskayuna, NY); Lacy, Benjamin Paul (Greer, SC)

    2012-05-15T23:59:59.000Z

    The low emission combustor includes a combustor housing defining a combustion chamber having a plurality of combustion zones. A liner sleeve is disposed in the combustion housing with a gap formed between the liner sleeve and the combustor housing. A secondary nozzle is disposed along a centerline of the combustion chamber and configured to inject a first fluid comprising air, at least one diluent, fuel, or combinations thereof to a downstream side of a first combustion zone among the plurality of combustion zones. A plurality of primary fuel nozzles is disposed proximate to an upstream side of the combustion chamber and located around the secondary nozzle and configured to inject a second fluid comprising air and fuel to an upstream side of the first combustion zone. The combustor also includes a plurality of tertiary coanda nozzles. Each tertiary coanda nozzle is coupled to a respective dilution hole. The tertiary coanda nozzles are configured to inject a third fluid comprising air, at least one other diluent, fuel, or combinations thereof to one or more remaining combustion zones among the plurality of combustion zones.

  10. Method to calibrate fission chambers in Campbelling mode

    SciTech Connect (OSTI)

    Geslot, Benoit; Filliatre, Philippe; Jammes, Christian; Di Salvo, Jacques; Breaud, Stephane; Villard, Jean-Francois [CEA, DEN, Cadarache, SPEx, LDCI, F-13108 S Paul Lez Durance, (France); Unruh, Troy C. [INL, Idaho Natl Lab, Idaho Falls, ID 83415 (United States)

    2012-08-15T23:59:59.000Z

    Fission chambers are neutron detectors which are widely used to instrument experimental reactors such as material testing reactors or zero power reactors. In the presence of a high level mixed gamma and neutron flux, fission chambers can be operated in Campbelling mode (also known as 'fluctuation mode' or 'mean square voltage mode') to provide reliable and precise neutron related measurements. Fission chamber calibration in Campbelling mode (in terms of neutron flux) is usually done empirically using a calibrated reference detector. A major drawback of this method is that calibration measurements have to be performed in a neutron environment very similar to the one in which the calibrated detector will be used afterwards. What is proposed here is a different approach based on characterizing the fission chamber response in terms of fission rate. This way, the detector calibration coefficient is independent from the neutron spectrum and can be determined prior to the experiment. The fissile deposit response to the neutron spectrum can then be assessed independently by other means (experimental or numerical). In this paper, the response of CEA-made miniature fission chambers in Campbelling mode is studied. A theoretical model of the signal is used to calculate the calibration coefficient. The model's input parameters come from statistical distribution of individual pulses. Supporting measurements were made in the CEA Cadarache zero power reactor MINERVE and results are compared to an empirical Campbelling mode calibration. The tested fission chamber calibration coefficient is roughly 2*10{sup -26} A{sup 2}/Hz/(c/s). Both numerical and empirical methods give consistent results, however a deviation of about 15% was observed. (authors)

  11. Chamber and target technology development for inertial fusion energy

    SciTech Connect (OSTI)

    Abdou, M; Besenbruch, G; Duke, J; Forman, L; Goodin, D; Gulec, K; Hoffer, J; Khater, H; Kulcinsky, G; Latkowski, J F; Logan, B G; Margevicious, B; Meier, W R; Moir, R W; Morley, N; Nobile, A; Payne, S; Peterson, P F; Peterson, R; Petzoldt, R; Schultz, K; Steckle, W; Sviatoslavsky, L; Tillack, M; Ying, A

    1999-04-07T23:59:59.000Z

    Fusion chambers and high pulse-rate target systems for inertial fusion energy (IFE) must: regenerate chamber conditions suitable for target injection, laser propagation, and ignition at rates of 5 to 10 Hz; extract fusion energy at temperatures high enough for efficient conversion to electricity; breed tritium and fuel targets with minimum tritium inventory; manufacture targets at low cost; inject those targets with sufficient accuracy for high energy gain; assure adequate lifetime of the chamber and beam interface (final optics); minimize radioactive waste levels and annual volumes; and minimize radiation releases under normal operating and accident conditions. The primary goal of the US IFE program over the next four years (Phase I) is to develop the basis for a Proof-of-Performance-level driver and target chamber called the Integrated Research Experiment (IRE). The IRE will explore beam transport and focusing through prototypical chamber environment and will intercept surrogate targets at high pulse rep-rate. The IRE will not have enough driver energy to ignite targets, and it will be a non-nuclear facility. IRE options are being developed for both heavy ion and laser driven IFE. Fig. 1 shows that Phase I is prerequisite to an IRE, and the IRE plus NIF (Phase II) is prerequisite to a high-pulse rate. Engineering Test Facility and DEMO for IFE, leading to an attractive fusion power plant. This report deals with the Phase-I R&D needs for the chamber, driver/chamber interface (i.e., magnets for accelerators and optics for lasers), target fabrication, and target injection; it is meant to be part of a more comprehensive IFE development plan which will include driver technology and target design R&D. Because of limited R&D funds, especially in Phase I, it is not possible to address the critical issues for all possible chamber and target technology options for heavy ion or laser fusion. On the other hand, there is risk in addressing only one approach to each technology option. Therefore, in the following description of these specific feasibility issues, we try to strike a balance between narrowing the range of recommended R&D options to minimize cost, and keeping enough R&D options to minimize risk.

  12. Single chamber fuel cells: Flow geometry, rate and composition considerations

    SciTech Connect (OSTI)

    Stefan, Ionel C.; Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2003-11-17T23:59:59.000Z

    Four different single chamber fuel cell designs were compared using propane-air gas mixtures. Gas flow around the electrodes has a significant influence on the open circuit voltage and the power density of the cell. The strong influence of flow geometry is likely due to its effect on gas composition, particularly on the oxygen chemical potential at the two electrodes as a result of gas mixing. The chamber design which exposes the cathode first to the inlet gas was found to yield the best performance at lower flow rates, while the open tube design with the electrodes equally exposed to the inlet gas worked best at higher flow rates.

  13. Depth and mineralogy of the magma source or pause region for the Carboniferous Liberty Hill pluton, South Carolina

    SciTech Connect (OSTI)

    Speer, J.A.

    1988-06-01T23:59:59.000Z

    Use of Al content geobarometry on clinopyroxene inclusions in plagioclase from the Carboniferous Liberty Hill pluton, South Carolina, yields pressure estimates of 8-10 kbar. Amphibole crystallization pressures are 3.1-4.7 kbar; contact metamorphic pressure are 4.5 kbar. Clinopyroxenes could be early crystallization products from the melt, restite crystals from the source region, xenocrysts from the magma conduit walls, or xenocrysts from a more mafic magma. Compositional uniformity of granitoid clinopyroxenes but dissimilarity with those in contemporaneous gabbroids is evidence against a xenocrystic origin. The deeper depths are interpreted as either the source region or a pausing place important in the crystallization history of the magma during its ascent to the upper crust. Early crystallization assemblage of the granitoid, and possibly the assemblage of the source region, was amphibole + clinopyroxene +/- plagioclase-bearing. An amphibolitic lower crustal source is consistent with the Sr and O isotopic and rare-earth-element studies of this and many other similar-age granitoids in the southern Appalachians.

  14. Matrix Algebra for GPU and Multicore Architectures (MAGMA) for Large Petascale Systems

    SciTech Connect (OSTI)

    Dongarra, Jack J. [University Distinguished Professor; Tomov, Stanimire [Research Scientist

    2014-03-24T23:59:59.000Z

    The goal of the MAGMA project is to create a new generation of linear algebra libraries that achieve the fastest possible time to an accurate solution on hybrid Multicore+GPU-based systems, using all the processing power that future high-end systems can make available within given energy constraints. Our efforts at the University of Tennessee achieved the goals set in all of the five areas identified in the proposal: 1. Communication optimal algorithms; 2. Autotuning for GPU and hybrid processors; 3. Scheduling and memory management techniques for heterogeneity and scale; 4. Fault tolerance and robustness for large scale systems; 5. Building energy efficiency into software foundations. The University of Tennessee’s main contributions, as proposed, were the research and software development of new algorithms for hybrid multi/many-core CPUs and GPUs, as related to two-sided factorizations and complete eigenproblem solvers, hybrid BLAS, and energy efficiency for dense, as well as sparse, operations. Furthermore, as proposed, we investigated and experimented with various techniques targeting the five main areas outlined.

  15. Computation of azimuthal combustion instabilities in an helicopter combustion chamber

    E-Print Network [OSTI]

    Nicoud, Franck

    Computation of azimuthal combustion instabilities in an helicopter combustion chamber C. Sensiau to compute azimuthal combustion instabilities is presented. It requires a thermoacoustic model using a n - formulation for the coupling between acoutics and combustion. The parameters n and are computed from a LES

  16. LASER FUSION CHAMBER DESIGN James P. Blanchard1

    E-Print Network [OSTI]

    Raffray, A. René

    the energy emitted by the target in such a way that the plant can achieve a commercially viable power approaches required for commercially viable laser fusion power plants, the issues driving those designs define the chamber size by providing flux limits for the various threats. In cases where a dry

  17. Thermodynamic Analysis of a single chamber Microbial Eric A. Zielke

    E-Print Network [OSTI]

    Thermodynamic Analysis of a single chamber Microbial Fuel Cell Eric A. Zielke May 5, 2006 #12;Microbial Fuel Cell Zielke ii List of Tables 1 First Law Thermodynamic Efficiencies from Experimental Data . . . . . . . 9 #12;Microbial Fuel Cell Zielke iii List of Figures 1 Representation of Anaerobic (anode portion

  18. QER- Comment of PA Chamber of Business and Industry

    Broader source: Energy.gov [DOE]

    On behalf of Gene Barr, President & CEO of the Pennsylvania Chamber of Business and Industry, please find attached our comments regarding Natural Gas Transmission, Storage & Distribution, Pittsburgh, Pennsylvania July 21, 2014. Thanks in advance for the attention to our comments and for holding a hearing today in our state. All the best, Kevin

  19. Modeling chamber transport for heavy-ion fusion

    SciTech Connect (OSTI)

    Sharp, W.M.; Callahan, D.A.; Tabak, M.; Yu, S.S.; Peterson, P.F.; Welch, D.R.; Rose, D.V.; Olson, C.L.

    2002-10-01T23:59:59.000Z

    In a typical thick-liquid-wall scenario for heavy-ion fusion (HIF), between seventy and two hundred high-current beams enter the target chamber through ports and propagate about three meters to the target. Since molten-salt jets are planned to protect the chamber wall, the beams move through vapor from the jets, and collisions between beam ions and this background gas both strip the ions and ionize the gas molecules. Radiation from the preheated target causes further beam stripping and gas ionization. Due to this stripping, beams for heavy-ion fusion are expected to require substantial neutralization in a target chamber. Much recent research has, therefore, focused on beam neutralization by electron sources that were neglected in earlier simulations, including emission from walls and the target, photoionization by the target radiation, and pre-neutralization by a plasma generated along the beam path. When these effects are included in simulations with practicable beam and chamber parameters, the resulting focal spot is approximately the size required by a distributed radiator target.

  20. Axial Ge/Si nanowire heterostructure tunnel FETs.

    SciTech Connect (OSTI)

    Dayeh, Shadi A. (Los Alamos National Laboratory); Gin, Aaron V.; Huang, Jian Yu; Picraux, Samuel Thomas (Los Alamos National Laboratory)

    2010-03-01T23:59:59.000Z

    Axial Ge/Si heterostructure nanowires (NWs) allow energy band-edge engineering along the axis of the NW, which is the charge transport direction, and the realization of asymmetric devices for novel device architectures. This work reports on two significant advances in the area of heterostructure NWs and tunnel FETs: (i) the realization of 100% compositionally modulated Si/Ge axial heterostructure NWs with lengths suitable for device fabrication and (ii) the design and implementation of Schottky barrier tunnel FETs on these NWs for high-on currents and suppressed ambipolar behavior. Initial prototype devices with 10 nm PECVD SiN{sub x} gate dielectric resulted in a very high current drive in excess of 100 {micro}A/{micro}m (I/{pi}D) and 10{sup 5} I{sub on}/I{sub off} ratios. Prior work on the synthesis of Ge/Si axial NW heterostructures through the VLS mechanism have resulted in axial Si/Si{sub 1-x}Ge{sub x} NW heterostructures with x{sub max} {approx} 0.3, and more recently 100% composition modulation was achieved with a solid growth catalyst. In this latter case, the thickness of the heterostructure cannot exceed few atomic layers due to the slow axial growth rate and concurrent radial deposition on the NW sidewalls leading to a mixture of axial and radial deposition, which imposes a big challenge for fabricating useful devices form these NWs in the near future. Here, we report the VLS growth of 100% doping and composition modulated axial Ge/Si heterostructure NWs with lengths appropriate for device fabrication by devising a growth procedure that eliminates Au diffusion on the NW sidewalls and minimizes random kinking in the heterostructure NWs as deduced from detailed microscopy analysis. Fig. 1 a shows a cross-sectional SEM image of epitaxial Ge/Si axial NW heterostructures grown on a Ge(111) surface. The interface abruptness in these Ge/Si heterostructure NWs is of the order of the NW diameter. Some of these NWs develop a crystallographic kink that is {approx}20{sup o} off the <111> axis at about 300 nm away from the Ge/Si interface. This provides a natural marker for placing the gate contact electrodes and gate metal at appropriate location for desired high-on current and reduced ambipolarity as shown in Fig. 2. The 1D heterostructures allow band-edge engineering in the transport direction, not easily accessible in planar devices, providing an additional degree of freedom for designing tunnel FETs (TFETs). For instance, a Ge tunnel source can be used for efficient electron/hole tunneling and a Si drain can be used for reduced back-tunneling and ambipolar behavior. Interface abruptness on the other hand (particularly for doping) imposes challenges in these structures and others for realizing high performance TFETs in p-i-n junctions. Since the metal-semiconductor contacts provide a sharp interface with band-edge control, we use properly designed Schottky contacts (aided by 3D Silvaco simulations) as the tunnel barriers both at the source and drain and utilize the asymmetry in the Ge/Si channel bandgap to reduce ambipolar transport behavior generally observed in TFETs. Fig. 3 shows the room-temperature transfer curves of a Ge/Si heterostructure TFET (H-TFET) for different V{sub DS} values showing a maximum on-current of {approx}7 {micro}A, {approx}170 mV/decade inverse subthreshold slope and 5 orders of magnitude I{sub on}/I{sub off} ratios for all V{sub DS} biases considered here. This high on-current value is {approx}1750 X higher than that obtained with Si p-i-n{sup +} NW TFETs and {approx}35 X higher than that obtained with CNT TFET. The I{sub on}/I{sub off} ratio and inverse subthreshold slope compare favorably to that of Si {approx} 10{sup 3} I{sub on}/I{sub off} and {approx} 800 mV/decade SS{sup -1} but lags behind those of CNT TFET due to poor PECVD nitride gate oxide quality ({var_epsilon}{sub r} {approx} 3-4). The asymmetry in the Schottky barrier heights used here eliminates the stringent requirements of abrupt doped interfaces used in p-i-n based TFETs, which is hard to achieve both in thin-film and

  1. Electrostatic waves in carbon nanotubes with an axial magnetic field

    SciTech Connect (OSTI)

    Abdikian, Alireza [Department of Physics, Malayer University, Malayer 65719-95863 (Iran, Islamic Republic of)] [Department of Physics, Malayer University, Malayer 65719-95863 (Iran, Islamic Republic of); Bagheri, Mehran [Laser and Plasma Research Institute, Shahid Beheshti University, G. C., Evin, Tehran 19835-63113 (Iran, Islamic Republic of)] [Laser and Plasma Research Institute, Shahid Beheshti University, G. C., Evin, Tehran 19835-63113 (Iran, Islamic Republic of)

    2013-10-15T23:59:59.000Z

    Based on a linearized hydrodynamic model and within the quasi-static approximation, the dispersion relation of electrostatic waves propagating through single-walled carbon nanotubes subject to an axial magnetic field is theoretically explored. In the classical limit, we obtain two main possible waves which in turn are divided into two branches, a low-frequency acoustical and a high-frequency optical plasmon branch. In the quantum case, we have found that the dispersion relation is substantially modified when the electron wavelength becomes large enough compared to the propagation wavelength of the electrostatic waves in the quantum plasma. We also show that the axial magnetic field manifest itself on the perturbed electron density through the quantum term and gives rise to the propagation of the electrostatic waves within the quantum plasma. As a result, the effect of the magnetic field is pronounced in the plasma dispersion relations in such a way that their curves approach to zero when the magnetic field is weak; and for the strong magnetic field, they asymptotically meet the constant lines.

  2. Competition between modes with different axial structures in gyrotrons

    SciTech Connect (OSTI)

    Khutoryan, Eduard M. [O. Ya. Usikov Institute for Radiophysics and Electronics, 12, Proskura str., Kharkiv 61085 (Ukraine); Nusinovich, Gregory S.; Sinitsyn, Oleksandr V. [Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742-3511 (United States)

    2014-09-15T23:59:59.000Z

    This study was motivated by some experiments in which it was found that during the voltage rise, instead of expected excitation of a high-frequency parasitic mode, the excitation of a lower-frequency parasitic mode takes place in a certain range of voltages. For explaining this fact, the dependence of start currents of possible competing modes on the beam voltage was carried out in the cold-cavity approximation and by using the self-consistent approach. It was found that in the case of cavities, which consist of the combination of a section of constant radius waveguide and a slightly uptapered waveguide, these two approaches yield completely different results. Thus, experimentally observed excitation of the low-frequency parasitic mode can be explained by the self-consistent modification of the axial profile of the excited field, which has strong influence on the diffractive quality factor of competing modes. This modification is especially pronounced in the case of excitation of modes with many axial variations which can be excited in the region of beam interaction with the backward-wave component of such modes.

  3. Maintenance and elimination of long-term axial progenitors in mouse 

    E-Print Network [OSTI]

    Wymeersch, Filip Jos

    2012-06-22T23:59:59.000Z

    Elongation of the vertebrate rostrocaudal axis depends on localised populations of axial progenitors. Previous work has demonstrated the presence of Neuromesodermal (NM) progenitors that behave a ...

  4. The $N-?$ Weak Axial-Vector Amplitude $C_{5}^a(0)$

    E-Print Network [OSTI]

    Milton Dean Slaughter

    1999-03-01T23:59:59.000Z

    The weak $N-\\Delta$ axial-vector transition amplitude $$ - important in $N^{*}$ production processes in general and in isobar models describing $\

  5. WPo4.9 SIMULATION OF IFE CHAMBER DYNAMIC RESPONSE BY A SECOND ORDER GODUNOV METHOD WITH ARBITRARY GEOMETRY

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    explosion. After the target-generated X-rays and ion debris traverse the chamber, the chamber environment scale occur in the chamber following the target explosion. The resultant X-rays, ion debris and neutron from the target travel through the chamber. Depending on the chamber constituents, X-rays and ion

  6. Shielding analysis for a heavy ion beam chamber with plasma channels for ion transport

    E-Print Network [OSTI]

    Sawan, M.E.; Peterson, R.R.; Yu, S.

    2000-01-01T23:59:59.000Z

    Analysis for a Heavy Ion Beam Chamber with Plasma Channelsthe target chamber wall, an adiabatic lens to focus the ionchamber that utilizes pre-formed plasma channels for heavy ion

  7. Cosmic Ray Test of Mini-drift Thick Gas Electron Multiplier Chamber for Transition Radiation Detector

    E-Print Network [OSTI]

    S. Yang; S. Das; B. Buck; C. Li; T. Ljubicic; R. Majka; M. Shao; N. Smirnov; G. Visser; Z. Xu; Y. Zhou

    2015-02-17T23:59:59.000Z

    A thick gas electron multiplier (THGEM) chamber with an effective readout area of 10$\\times$10 cm$^{2}$ and a 11.3 mm ionization gap has been tested along with two regular gas electron multiplier (GEM) chambers in a cosmic ray test system. The thick ionization gap makes the THGEM chamber a mini-drift chamber. This kind mini-drift THGEM chamber is proposed as part of a transition radiation detector (TRD) for identifying electrons at an Electron Ion Collider (EIC) experiment. Through this cosmic ray test, an efficiency larger than 94$\\%$ and a spatial resolution $\\sim$220 $\\mu$m are achieved for the THGEM chamber at -3.65 kV. Thanks to its outstanding spatial resolution and thick ionization gap, the THGEM chamber shows excellent track reconstruction capability. The gain uniformity and stability of the THGEM chamber are also presented.

  8. Passivity Based Adaptive Control of a Two Chamber Single Rod Hydraulic Actuator

    E-Print Network [OSTI]

    Li, Perry Y.

    Passivity Based Adaptive Control of a Two Chamber Single Rod Hydraulic Actuator Meng Wang and Perry based backstepping controller using a physical compressibility energy function for a chamber hydraulic produces an accurate trajectory tracking performance. I. INTRODUCTION Electronically controlled hydraulic

  9. SciTech Connect: ON THE ANALYSIS OF BUBBLE CHAMBER TRACKS

    Office of Scientific and Technical Information (OSTI)

    THE ANALYSIS OF BUBBLE CHAMBER TRACKS Citation Details In-Document Search Title: ON THE ANALYSIS OF BUBBLE CHAMBER TRACKS Since its invention by Glaser in 1953, the bubble...

  10. Nuclear reactor control rod with uniformly changeable axial worth

    SciTech Connect (OSTI)

    Freeman, T.R.

    1989-04-11T23:59:59.000Z

    A control rod is described for use in a nuclear reactor core to provide xenon compensation, comprising: (a) an elongated inner cylindrical member having a lower end; and (b) an elongated outer cylindrical member surrounding the inner member and having a lower end with concentrically-arranged inner and outer edge portions defined thereon; (c) each of the members being composed of alternating poison and nonpoison regions; (d) the inner member being axially movable relative to the outer member to adjust the degree to which the poison regions of the members overlap with the nonpoison regions thereof and thereby change the overall worth of the rod; and (e) the lower end of the inner member having defined thereon a radially outwardly projecting ledge for supporting in a rest relationship thereon the lower end of the outer member at only its inner edge portion for retaining the outer member about the inner member.

  11. Feedback control of inertial microfluidics using axial control forces

    E-Print Network [OSTI]

    Prohm, Christopher

    2014-01-01T23:59:59.000Z

    Inertial microfluidics is a promising tool for many lab-on-a-chip applications. Particles in channel flows with Reynolds numbers above one undergo cross-streamline migration to a discrete set of equilibrium positions in square and rectangular channel cross sections. This effect has been used extensively for particle sorting and the analysis of particle properties. Using the lattice Boltzmann method, we determine equilibrium positions in square and rectangular cross sections and classify their types of stability for different Reynolds numbers, particle sizes, and channel aspect ratios. Our findings thereby help to design microfluidic channels for particle sorting. Furthermore, we demonstrate how an axial control force, which slows down the particles, shifts the stable equilibrium position towards the channel center. Ultimately, the particles then stay on the centerline for forces exceeding a threshold value. This effect is sensitive to particle size and channel Reynolds number and therefore suggests an efficie...

  12. Nucleon axial form factors from two-flavour Lattice QCD

    E-Print Network [OSTI]

    P. M. Junnarkar; S. Capitani; D. Djukanovic; G. von Hippel; J. Hua; B. Jäger; H. B. Meyer; T. D. Rae; H. Wittig

    2014-11-21T23:59:59.000Z

    We present preliminary results on the axial form factor $G_A(Q^2)$ and the induced pseudoscalar form factor $G_P(Q^2)$ of the nucleon. A systematic analysis of the excited-state contributions to form factors is performed on the CLS ensemble `N6' with $m_\\pi = 340 \\ \\text{MeV}$ and lattice spacing $a \\sim 0.05 \\ \\text{fm}$. The relevant three-point functions were computed with source-sink separations ranging from $t_s \\sim 0.6 \\ \\text{fm}$ to $t_s \\sim \\ 1.4 \\ \\text{fm}$. We observe that the form factors suffer from non-trivial excited-state contributions at the source-sink separations available to us. It is noted that naive plateau fits underestimate the excited-state contributions and that the method of summed operator insertions correctly accounts for these effects.

  13. The Laser Calibration System of the ALICE Time Projection Chamber

    E-Print Network [OSTI]

    G. Renault; B. S. Nielsen; J. Westergaard; J. J. Gaardhøje

    2005-11-07T23:59:59.000Z

    A Large Ion Collider Experiment (ALICE) is the only experiment at the Large Hadron Collider (LHC) dedicated to the study of heavy ion collisions. The Time Projection Chamber (TPC) is the main tracking detector covering the pseudo rapidity range $|\\eta|laser system is to simulate ionizing tracks at predifined positions throughout the drift volume in order to monitor the TPC response to a known source. In particular, the alignment of the read-out chambers will be performed, and variations of the drift velocity due to drift field imperfections can be measured and used as calibration data in the physics data analysis. In this paper we present the design of the pulsed UV laser and optical system, together with the control and monitoring systems.

  14. Chamber for the optical manipulation of microscopic particles

    DOE Patents [OSTI]

    Buican, Tudor N. (Los Alamos, NM); Upham, Bryan D. (Los Alamos, NM)

    1992-01-01T23:59:59.000Z

    A particle control chamber enables experiments to be carried out on biological cells and the like using a laser system to trap and manipulate the particles. A manipulation chamber provides a plurality of inlet and outlet ports for the particles and for fluids used to control or to contact the particles. A central manipulation area is optically accessible by the laser and includes first enlarged volumes for containing a selected number of particles for experimentation. A number of first enlarged volumes are connected by flow channels through second enlarged volumes. The second enlarged volumes act as bubble valves for controlling the interconnections between the first enlarged volumes. Electrode surfaces may be applied above the first enlarged volumes to enable experimentation using the application of electric fields within the first enlarged volumes. A variety of chemical and environmental conditions may be established within individual first enlarged volumes to enable experimental conditions for small scale cellular interactions.

  15. HOM Sensitivity in the PEP-II HER Vacuum Chamber

    SciTech Connect (OSTI)

    Weathersby, Stephen; Novokhatski, Alexander; Sullivan, Mike; /SLAC

    2010-02-10T23:59:59.000Z

    Synchrotron radiation is the main source of vacuum chamber heating in the PEP-II storage ring collider. This heating is reduced substantially as lattice energy is lowered. Energy scans over {Upsilon} energy states were performed by varying the high energy ring (HER) lattice energy at constant gap voltage and frequency. We observed unexpected temperature rise at particular locations when HER lattice energy was lowered from 8.6 GeV ({Upsilon}(3S)) to 8.0 GeV ({Upsilon}(2S)) while most other temperatures decreased. Bunch length measurements reveal a shorter bunch at the lower energy. The shortened bunch overheated a beam position monitoring electrode causing a vacuum breach. We explain the unexpected heating as a consequence of increased higher order mode (HOM) power generated by a shortened bunch. In this case, temperature rise helps to identify HOM sources and HOM sensitive vacuum chamber elements. Reduction of gap voltage helps to reduce this unexpected heating.

  16. Combustion of Shock-Dispersed Fuels in a Chamber

    SciTech Connect (OSTI)

    Neuwald, P; Reichenbach, H; Kuhl, A L

    2003-04-23T23:59:59.000Z

    In previous studies we have investigated after-burning effects of a fuel-rich explosive (TNT). In that case the detonation only releases about 30 % of the available energy, but generates a hot cloud of fuel that can burn in the ambient air, thus evoking an additional energy release that is distributed in space and time. The current series of small-scale experiments can be looked upon as a natural generalization of this mechanism: a booster charge disperses a (non-explosive) fuel, provides mixing with air and - by means of the hot detonation products - energy to ignite the fuel. The current version of our miniature Shock-Dispersed-Fuel (SDF) charges consists of a spherical booster charge of 0.5 g PETN, embedded in a paper cylinder of approximately 2.2 cm3, which is filled with powdered fuel compositions. The main compositions studied up to now contain aluminum powder, hydrocarbon powders like polyethylene or sucrose and/or carbon particles. These charges were studied in three different chambers of 4-1, 6.6-1 and 40.5-1 volume. In general, the booster charge was sufficient to initiate burning of the fuel. This modifies the pressure signatures measured with a number of wall gages and increases the quasi-static overpressure level obtained in the chambers. On the one hand the time-scale and the yield of the pressure rise depend on the fuel and its characteristics. On the other hand they also depend on the flow dynamics in the chamber, which is dominated by shock reverberations, and thus on the chamber geometry and volume. The paper gives a survey of the experimental results and discusses the possible influences of some basic parameters.

  17. Using sputter coated glass to stabilize microstrip gas chambers

    DOE Patents [OSTI]

    Gong, Wen G. (Albany, CA)

    1997-01-01T23:59:59.000Z

    By sputter coating a thin-layer of low-resistive, electronically-conductive glass on various substrates (including quartz and ceramics, thin-film Pestov glass), microstrip gas chambers (MSGC) of high gain stability, low leakage current, and a high rate capability can be fabricated. This design can make the choice of substrate less important, save the cost of ion-implantation, and use less glass material.

  18. Low Pressure Negative Ion Drift Chamber for Dark Matter Search

    E-Print Network [OSTI]

    D. P. Snowden-Ifft; C. J. Martoff; J. M. Burwell

    1999-04-06T23:59:59.000Z

    Weakly Interacting Massive Particles (WIMPs) are an attractive candidate for the dark matter thought to make up the bulk of the mass of our universe. We explore here the possibility of using a low pressure negative ion drift chamber to search for WIMPs. The innovation of drifting ions, instead of electrons, allows the design of a detector with exceptional sensitivity to, background rejection from, and signature of WIMPs.

  19. Ion Chamber Arrays for the Numi Beam at Fermilab

    E-Print Network [OSTI]

    D. Indurthy; Z. Pavlovic; R. Zwaska; R. Keisler; S. Mendoza; S. Kopp; M. Proga; D. Harris; A. Marchionni; J. Morfin; A. Erwin; H. Ping; C. Velissaris; M. Bishai; M. Diwan; B. Viren; D. Naples; D. Northacker; J. McDonald

    2005-06-26T23:59:59.000Z

    The Neutrinos at the Main Injector (NuMI) beamline will deliver an intense muon neutrino beam by focusing a beam of mesons into a long evacuated decay volume. We have built 4 arrays of ionization chambers to monitor the neutrino beam direction and quality. The arrays are located at 4 stations downstream of the decay volume, and measure the remnant hadron beam and tertiary muons produced along with neutrinos in meson decays.

  20. Progress and critical issues for IFE blanket and chamber research

    SciTech Connect (OSTI)

    Abdou, M.; Kulcinski, G.L.; Latkowski, J.F.; Logan, B.G.; Meier, W.R.; Moir, R.W.; Nobile, A.; Peterson, P.F.; Petti, D.; Schultz, K.R.; Tillack, M.S.

    1999-06-23T23:59:59.000Z

    Advances in high gain target designs for Inertial Fusion Energy (IFE), and the initiation of construction of large megajoule-class laser facilities in the U.S. (National Ignition Facility) and France (Laser-Megajoule) capable of testing the requirements for inertial fusion ignition and propagating burn, have improved the prospects for IFE. Accordingly, there have recently been modest increases in the US fusion research program related to the feasibility of IFE. These research areas include heavy-ion accelerators, Krypton-Fluoride (KrF) gas lasers, diode-pumped, solid-state (DPSSL) lasers, IFE target designs for higher gains, feasibility of low cost IFE target fabrication and accurate injection, and long-lasting IFE fusion chambers and final optics. Since several studies of conceptual IFE power plant and driver designs were completed in 1992-1996 [1-5], U.S. research in the IFE blanket, chamber, and target technology areas has focused on the critical issues relating to the feasibility of IFE concepts towards the goal of achieving economically-competitive and environmentally-attractive fusion energy. This paper discusses the critical issues in these areas, and the approaches taken to address these issues. The U.S. research in these areas, called IFE Chamber and Target Technologies, is coordinated through the Virtual Laboratory for Technology (VLT) formed by the Department of Energy in December 1998.

  1. Dry Chamber Wall Thermo-Mechanical Behavior and Lifetime under IFE Cyclic Energy Deposition

    E-Print Network [OSTI]

    California at San Diego, University of

    assessment of dry chamber wall based on ion and photon spectra from a new direct-drive target proposed by NRLDry Chamber Wall Thermo-Mechanical Behavior and Lifetime under IFE Cyclic Energy Deposition Lifetime is a key issue for the IFE dry chamber wall configuration. Past studies, such as SOMBRERO

  2. IMPACT OF BEAM TRANSPORT METHOD ON CHAMBER AND DRIVER DESIGN FOR

    E-Print Network [OSTI]

    IMPACT OF BEAM TRANSPORT METHOD ON CHAMBER AND DRIVER DESIGN FOR HEAVY ION INERTIAL FUSION ENERGY D propagate in thick-liquid-wall, wetted-wall, and dry-wall chambers. KEYWORDS: heavy ion fusion, ion beam transport, reactor chamber design I. INTRODUCTION The U.S. heavy ion fusion ~HIF! program is working toward

  3. September 29, 2008 TOFE08, San Francisco 1 Laser IFE Direct Drive Chamber Concepts with

    E-Print Network [OSTI]

    Raffray, A. René

    ion threat with dry chamber wall · Magnetic intervention as advanced option to reduce or eliminate ion MJ target (~24% of the energy is in ions and ~1% in photons), a large chamber (~10.75 m) is required chamber as baseline and look at options to accommodate ion threat spectra on the armor. - Engineered armor

  4. Characterization and performances of a monitoring ionization chamber dedicated to IBA-universal

    E-Print Network [OSTI]

    an Ionization Chamber in col- laboration with the company IBA (Ion Beam Applications). This monitoring deviceCharacterization and performances of a monitoring ionization chamber dedicated to IBA patented and five IC2/3 chambers were de- Preprint submitted to Elsevier June 28, 2013 in2p3

  5. IFE chamber walls: requirements, design options, and synergy with MFE plasma facing components

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    rights reserved. PACS: 52.40.H Keywords: Internal fusion; Chamber wall material; X-ray deposition; Ion and ion energy deposition while providing the required lifetime. Chamber concepts utilizing both solid injected into the chamber. The driver (laser or heavy ion) beam is focused on the target, compressing

  6. Dry Chamber Wall Thermo-Mechanical Behavior and Lifetime under IFE Cyclic Energy Deposition

    E-Print Network [OSTI]

    Raffray, A. René

    provided a more detailed assessment of dry chamber wall based on ion and photon spectra from a new direct much faster than the ions and would reach the chamber wall within about 20 ns in the case without protective gas. The ions take longer to reach the chamber wall. As an example, a simple estimate of the ion

  7. CLOUD CHAMBER: A PERFORMANCE INVOLVING REAL TIME TWO-WAY INTERACTION BETWEEN SUBATOMIC RADIOACTIVE

    E-Print Network [OSTI]

    Miranda, Eduardo Reck

    " by the radiation-generated ion patterns in the glass chamber. If John plays in one way the ion particlesCLOUD CHAMBER: A PERFORMANCE INVOLVING REAL TIME TWO-WAY INTERACTION BETWEEN SUBATOMIC RADIOACTIVE, Harwell, Oxford, UK ABSTRACT ,,Cloud Chamber is a live performance created by composer Alexis Kirke

  8. October 27-28, 2004 HAPL meeting, PPPL Overview of the Components of an IFE Chamber

    E-Print Network [OSTI]

    Raffray, A. René

    of MFE design and R&D info) System (including power cycle) Dry wall chamber (armor must accommodate ion Spectra and Chamber Conditions Prior to Each Shot Must Be Well Characterized (UW) · Attenuation of ion 29% 48% Re-radiation Time Scale (µs) 300-700 300-700 Chamber Gas Ion and Photon Attenuation

  9. Dec 12-13, 2006 HAPL meeting, PPPL Advanced Chamber Concept with Magnetic Intervention

    E-Print Network [OSTI]

    Raffray, A. René

    Dec 12-13, 2006 HAPL meeting, PPPL 1 Advanced Chamber Concept with Magnetic Intervention: - Ion; provision of samples for additional testing elsewhere to follow. · Separate ion dump chamber for magnetic-change dry wall or wetted wall chamber to accommodate ions and provide long life. · Have to make sure

  10. IFSA, Kyoto, Japan, September 2001 1 Dry Chamber Wall Thermo-Mechanical Behavior

    E-Print Network [OSTI]

    Raffray, A. René

    assessment of dry chamber wall [6] based on ion and photon spectra from new direct-drive target from NRL [3 for an Example Case Without a Protective Chamber Gas #12;IFSA, Kyoto, Japan, September 2001 8 Photon and Ion Time of Temporal Distribution for Photons and Ions Based on Direct Drive Spectrum and 6.5 m Chamber without

  11. Technique to Collimate Ions in a Hall-Effect Thruster Discharge Chamber

    E-Print Network [OSTI]

    Walker, Mitchell

    Technique to Collimate Ions in a Hall-Effect Thruster Discharge Chamber Kunning G. Xu and Mitchell in the discharge chamber to repel ions away from the wall and focus them toward centerline. The electrodes repel ions with trajectories that intersect the chamber wall, which results in a more collimated ion exhaust

  12. March 21-22, 2006 HAPL meeting, ORNL Status of Chamber and Blanket Effort

    E-Print Network [OSTI]

    Raffray, A. René

    Spectra Spectra in a 10.75 m Chamber #12;March 21-22, 2006 HAPL meeting, ORNL 5 Smoothness of Plot of Ion Plates Estimated for Cone-Shaped Chamber · Duck bill configuration assumed for the equatorial ion dumpMarch 21-22, 2006 HAPL meeting, ORNL 1 Status of Chamber and Blanket Effort A. René Raffray UCSD

  13. MOBILITIES OF POSITIVE IONS IN SOME GAS MIXTURES USED IN PROPORTIONAL AND DRIFT CHAMBERS

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    67 MOBILITIES OF POSITIVE IONS IN SOME GAS MIXTURES USED IN PROPORTIONAL AND DRIFT CHAMBERS G proportional chambers or drift chambers with gas mixtures, using isobutane as a quencher. The positive ions, révisé le 11 juin 1976, accepté le 2 septembre 1976) Résumé. 2014 Le coefficient de mobilité des ions

  14. Recent advances in single-chamber fuel-cells: Experiment and modeling , Zongping Shao b

    E-Print Network [OSTI]

    Haile, Sossina M.

    Recent advances in single-chamber fuel-cells: Experiment and modeling Yong Hao a , Zongping Shao b; accepted 6 May 2006 Abstract Single-chamber fuel cells (SCFC) are ones in which the fuel and oxidizer is discussed. © 2006 Elsevier B.V. All rights reserved. Keywords: Solid oxide fuel cell; Single chamber

  15. Complete fabrication of target experimental chamber and implement initial target diagnostics to be used for the first target experiments in NDCX-1

    E-Print Network [OSTI]

    Bieniosek, F.M.

    2008-01-01T23:59:59.000Z

    Drift Compression Magnet Chamber Ion Beam Background Plasmaand reheating of the ion source, the target chamber can betarget chamber ports are reserved for ion beam diagnostics

  16. A Moore-Greitzer axial compressor model with spool Jan Tommy Gravdahl and Olav Egeland

    E-Print Network [OSTI]

    Gravdahl, Jan Tommy

    A Moore-Greitzer axial compressor model with spool dynamics. Jan Tommy Gravdahl and Olav Egeland, N-7034 Trondheim, Norway Email: fTommy.Gravdahl,Olav.Egelandg@itk.ntnu.no Abstract The compressor-parameter on the post stall transients of an axial compressor is demonstrated through simulations of a compression

  17. On the linear stability of the extreme Kerr black hole under axially symmetric perturbations

    E-Print Network [OSTI]

    Sergio Dain; Ivan Gentile de Austria

    2014-09-19T23:59:59.000Z

    We prove that for axially symmetric linear gravitational perturbations of the extreme Kerr black hole there exists a positive definite and conserved energy. This provides a basic criteria for linear stability in axial symmetry. In the particular case of Minkowski, using this energy we also prove pointwise boundedness of the perturbation in a remarkable simple way.

  18. Axial dispersion in segmented gas-liquid flow: Effects of alternating channel curvature

    E-Print Network [OSTI]

    Muradoglu, Metin

    processes such as two-phase catalytic monolith reactors,3­6 polymer blow molding, enhanced oil recovery,7 is periodically broken in the serpentine channel leading to enhanced axial dispersion. It is also found channel geometries. In addition to the enhanced mix- ing, the segmentation also reduces the axial

  19. 1 Mayne & Schneider EVALUATING AXIAL DRILLED SHAFT RESPONSE BY SEISMIC CONE

    E-Print Network [OSTI]

    Mayne, Paul W.

    1 Mayne & Schneider EVALUATING AXIAL DRILLED SHAFT RESPONSE BY SEISMIC CONE Paul W. Mayne1 , M using the results of seismic piezocone penetration tests (SCPTU) to provide continuous profiles of small to discuss the use of seismic piezocone testing for the evaluation of both axial capacity (obtained from

  20. Tuning linear and nonlinear optical properties of wurtzite GaN by c-axial stress

    E-Print Network [OSTI]

    Cai, Duanjun; 10.1088/0022-3727/42/18/185107

    2009-01-01T23:59:59.000Z

    We study the linear and nonlinear optical properties of wurtzite GaN under c-axial stress field, using density functional theory calculations. The fully structural optimization at each c-axial strain was performed. The calculated dielectric functions show that tensile c-axial strain effectively improves the linear optical efficiency, especially for the band-edge transitions, and significantly increase the mobility of electrons in the conduction band. Second-order nonlinear optical susceptibilities show that the tensile c-axial strain will enhance the zero- and low-frequency nonlinear responses of GaN. The enhancement of the nonlinear optical property is explained by the reduction of the polarization of wurtzite GaN under tensile c-axial strains. Based on these findings, we propose a method for improving the electrical and optical properties of the crystal through imposing appropriate stress on the high symmetry crystalline directions.

  1. Dispersion relation and growth rate in a Cherenkov free electron laser: Finite axial magnetic field

    SciTech Connect (OSTI)

    Kheiri, Golshad; Esmaeilzadeh, Mahdi [Department of Physics, Iran University of Science and Technology, Tehran 16844 (Iran, Islamic Republic of)] [Department of Physics, Iran University of Science and Technology, Tehran 16844 (Iran, Islamic Republic of)

    2013-12-15T23:59:59.000Z

    A theoretical analysis is presented for dispersion relation and growth rate in a Cherenkov free electron laser with finite axial magnetic field. It is shown that the growth rate and the resonance frequency of Cherenkov free electron laser increase with increasing axial magnetic field for low axial magnetic fields, while for high axial magnetic fields, they go to a saturation value. The growth rate and resonance frequency saturation values are exactly the same as those for infinite axial magnetic field approximation. The effects of electron beam self-fields on growth rate are investigated, and it is shown that the growth rate decreases in the presence of self-fields. It is found that there is an optimum value for electron beam density and Lorentz relativistic factor at which the maximum growth rate can take place. Also, the effects of velocity spread of electron beam are studied and it is found that the growth rate decreases due to the electron velocity spread.

  2. Dual chamber system providing simultaneous etch and deposition on opposing substrate sides for growing low defect density epitaxial layers

    DOE Patents [OSTI]

    Kulkarni, Nagraj S. (Knoxville, TN); Kasica, Richard J. (Ashburn, VA) ,

    2011-03-08T23:59:59.000Z

    A dual-chamber reactor can include a housing enclosing a volume having a divider therein, where the divider defines a first chamber and a second chamber. The divider can include a substrate holder that supports at least one substrate and exposes a first side of the substrate to the first chamber and a second side of the substrate to the second chamber. The first chamber can include an inlet for delivering at least one reagent to the first chamber for forming a film on the first side of the substrate, and the second chamber can include a removal device for removing material from the second side of the substrate.

  3. Lifetime and Spectral Evolution of a Magma Ocean with a Steam Atmosphere: Its Detectability by Future Direct Imaging

    E-Print Network [OSTI]

    Hamano, Keiko; Abe, Yutaka; Onishi, Masanori; Hashimoto, George L

    2015-01-01T23:59:59.000Z

    We present the thermal evolution and emergent spectra of solidifying terrestrial planets along with the formation of steam atmospheres. The lifetime of a magma ocean and its spectra through a steam atmosphere depends on the orbital distance of the planet from the host star. For a type-I planet, which is formed beyond a certain critical distance from the host star, the thermal emission declines on a timescale shorter than approximately $10^6$ years. Therefore, young stars should be targets when searching for molten planets in this orbital region. In contrast, a type-II planet, which is formed inside the critical distance, will emit significant thermal radiation from near-infrared atmospheric windows during the entire lifetime of the magma ocean. The Ks and L bands will be favorable for future direct imaging because the planet-to-star contrasts of these bands are higher than approximately 10$^{-7}$-10$^{-8}$. Our model predicts that, in the type-II orbital region, molten planets would be present over the main s...

  4. Performance parameters of a liquid filled ionization chamber array

    SciTech Connect (OSTI)

    Poppe, B.; Stelljes, T. S.; Looe, H. K.; Chofor, N. [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121, Germany and WG Medical Radiation Physics, Carl von Ossietzky University, Oldenburg 26121 (Germany)] [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121, Germany and WG Medical Radiation Physics, Carl von Ossietzky University, Oldenburg 26121 (Germany); Harder, D. [Prof. em., Medical Physics and Biophysics, Georg August University, Göttingen 37073 (Germany)] [Prof. em., Medical Physics and Biophysics, Georg August University, Göttingen 37073 (Germany); Willborn, K. [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121 (Germany)] [Clinic for Radiation Therapy, Pius-Hospital, Oldenburg 26121 (Germany)

    2013-08-15T23:59:59.000Z

    Purpose: In this work, the properties of the two-dimensional liquid filled ionization chamber array Octavius 1000SRS (PTW-Freiburg, Germany) for use in clinical photon-beam dosimetry are investigated.Methods: Measurements were carried out at an Elekta Synergy and Siemens Primus accelerator. For measurements of stability, linearity, and saturation effects of the 1000SRS array a Semiflex 31013 ionization chamber (PTW-Freiburg, Germany) was used as a reference. The effective point of measurement was determined by TPR measurements of the array in comparison with a Roos chamber (type 31004, PTW-Freiburg, Germany). The response of the array with varying field size and depth of measurement was evaluated using a Semiflex 31010 ionization chamber as a reference. Output factor measurements were carried out with a Semiflex 31010 ionization chamber, a diode (type 60012, PTW-Freiburg, Germany), and the detector array under investigation. The dose response function for a single detector of the array was determined by measuring 1 cm wide slit-beam dose profiles and comparing them against diode-measured profiles. Theoretical aspects of the low pass properties and of the sampling frequency of the detector array were evaluated. Dose profiles measured with the array and the diode detector were compared, and an intensity modulated radiation therapy (IMRT) field was verified using the Gamma-Index method and the visualization of line dose profiles.Results: The array showed a short and long term stability better than 0.1% and 0.2%, respectively. Fluctuations in linearity were found to be within ±0.2% for the vendor specified dose range. Saturation effects were found to be similar to those reported in other studies for liquid-filled ionization chambers. The detector's relative response varied with field size and depth of measurement, showing a small energy dependence accounting for maximum signal deviations of ±2.6% from the reference condition for the setup used. The ?-values of the Gaussian dose response function for a single detector of the array were found to be (0.72 ± 0.25) mm at 6 MV and (0.74 ± 0.25) mm at 15 MV and the corresponding low pass cutoff frequencies are 0.22 and 0.21 mm{sup ?1}, respectively. For the inner 5 × 5 cm{sup 2} region and the outer 11 × 11 cm{sup 2} region of the array the Nyquist theorem is fulfilled for maximum sampling frequencies of 0.2 and 0.1 mm{sup ?1}, respectively. An IMRT field verification with a Gamma-Index analysis yielded a passing rate of 95.2% for a 3 mm/3% criterion with a TPS calculation as reference.Conclusions: This study shows the applicability of the Octavius 1000SRS in modern dosimetry. Output factor and dose profile measurements illustrated the applicability of the array in small field and stereotactic dosimetry. The high spatial resolution ensures adequate measurements of dose profiles in regular and intensity modulated photon-beam fields.

  5. Feedback control of inertial microfluidics using axial control forces

    E-Print Network [OSTI]

    Christopher Prohm; Holger Stark

    2014-02-03T23:59:59.000Z

    Inertial microfluidics is a promising tool for many lab-on-a-chip applications. Particles in channel flows with Reynolds numbers above one undergo cross-streamline migration to a discrete set of equilibrium positions in square and rectangular channel cross sections. This effect has been used extensively for particle sorting and the analysis of particle properties. Using the lattice Boltzmann method, we determine equilibrium positions in square and rectangular cross sections and classify their types of stability for different Reynolds numbers, particle sizes, and channel aspect ratios. Our findings thereby help to design microfluidic channels for particle sorting. Furthermore, we demonstrate how an axial control force, which slows down the particles, shifts the stable equilibrium position towards the channel center. Ultimately, the particles then stay on the centerline for forces exceeding a threshold value. This effect is sensitive to particle size and channel Reynolds number and therefore suggests an efficient method for particle separation. In combination with a hysteretic feedback scheme, we can even increase particle throughput.

  6. Reliability of steam generator tubes with axial cracks

    SciTech Connect (OSTI)

    Cizelj, L.; Mavko, B. [Jozef Stefan Inst., Ljubljana (Slovenia). Reactor Engineering Div.; Vencelj, P. [Univ. of Ljubljana (Slovenia). Faculty of Mathematics and Physics

    1996-11-01T23:59:59.000Z

    An approach for estimating the failure probability of tubes containing through-wall axial cracks has already been proposed by the authors. It is based on probabilistic fracture mechanics and accounts for scatter in tube geometry and material properties, scatter in residual and operational stresses responsible for crack propagation, and characteristics of nondestructive examination and plugging procedures (e.g., detection probability, sizing accuracy, human errors). Results of preliminary tests demonstrated wide applicability of this approach and triggered some improvements. The additions to the model are extensively discussed in this paper. Capabilities are demonstrated by results of analysis of steam generator no. 1 in Slovenian nuclear power plant located in Krsko after the 1992 inspection and plugging campaign. First, the number of cracked tubes and the crack length distribution were estimated using data obtained by the 100% motorized pancake coil inspection. The inspection and plugging activities were simulated in the second step to estimate the efficiency of maintenance in terms of single and multiple-tube rupture probabilities. They were calculated as a function of maximum allowable crack length. The importance of human errors and some limitations of present nondestructive examination techniques were identified. The traditional wall thickness and crack-length-based plugging criteria are compared. The crack-length-based criterion is shown to be more efficient and more safe, especially because of strong suppression effect on probability of multiple-tube rupture. The results are considered to be important for safety and maintenance of existing plants and for further research.

  7. Nov 13-14, 2001 A. R. Raffray, et al., Progress Report on Chamber Clearing Code Effort 1 Progress Report on Chamber Clearing Code

    E-Print Network [OSTI]

    Raffray, A. René

    Nov 13-14, 2001 A. R. Raffray, et al., Progress Report on Chamber Clearing Code Effort 1 Progress Livermore November 13-14, 2001 #12;Nov 13-14, 2001 A. R. Raffray, et al., Progress Report on Chamber.g. - CFDRC - HEIGHTS - RECON · Code implementation and integration of packages #12;Nov 13-14, 2001 A. R

  8. Statistics of the electromagnetic response of a chaotic reverberation chamber

    E-Print Network [OSTI]

    J. -B. Gros; U. Kuhl; O. Legrand; F. Mortessagne; O. Picon; E. Richalot

    2014-09-20T23:59:59.000Z

    This article presents a study of the electromagnetic response of a chaotic reverberation chamber (RC) in the presence of losses. By means of simulations and of experiments, the fluctuations in the maxima of the field obtained in a conventional mode-stirred RC are compared with those in a chaotic RC in the neighborhood of the Lowest Useable Frequency (LUF). The present work illustrates that the universal spectral and spatial statistical properties of chaotic RCs allow to meet more adequately the criteria required by the Standard IEC 61000-4-21 to perform tests of electromagnetic compatibility.

  9. Long ion chamber systems for the SLC (Stanford Linear Collider)

    SciTech Connect (OSTI)

    Rolfe, J.; Gearhart, R.; Jacobsen, R.; Jenkins, T.; McComick, D.; Nelson, R.; Reagan, D.; Ross, M.

    1989-03-01T23:59:59.000Z

    A Panofsky Long Ion Chamber (PLIC) is essentially a gas-filled coaxial cable, and has been used to protect the Stanford Linear Accelerator from damage caused by its electron beam, and as a sensitive diagnostic tool. This old technology has been updated and has found renewed use in the SLC. PLIC systems have been installed as beam steering aids in most parts of the SLC and are a part of the system that protects the SLC from damage by errant beams in several places. 5 refs., 3 figs., 1 tab.

  10. Development of the Captive Aerosol Growth and Evolution Chamber System 

    E-Print Network [OSTI]

    Antonietti, Carlos G

    2014-08-28T23:59:59.000Z

    that are alternated between the two using 3-way valves. There are two Teflon ports for gases and a stainless steel port for aerosol injection and withdrawal. The walls of the room are covered with UV-reflective aluminum panels. A 54 kW air conditioning system... W black lights. The walls of the room are covered with reflective aluminum panels. During operation the inlet and outlet flow rates are matched. The University of California at Riverside environmental chamber consists of two ~90 m3 Teflon bags...

  11. Continuous Flow Diffusion Chamber Measurements of IN Concentration

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power Administration would likeConstitution And Bylaws |ContactFlow Diffusion Chamber (CFDC)

  12. Santa Fe Chamber of Commerce Business Awards Gala

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiationImplementingnpitcheResearch Briefs TheSanket A. Deshmukh ArgonneSanta Fe Chamber

  13. EXPERIMENTAL AND NUMERICAL ANALYSIS OF THE FLOW INSIDE A CONFIGURATION INCLUDING AN AXIAL PUMP AND A TUBULAR

    E-Print Network [OSTI]

    Boyer, Edmond

    EXPERIMENTAL AND NUMERICAL ANALYSIS OF THE FLOW INSIDE A CONFIGURATION INCLUDING AN AXIAL PUMP-30723) In centrifugal and axial pumps, the flow is characterized by a turbulent and complex behavior and also of a configuration that includes an axial pump and a bundle of tubes that mimics the cool source of a heat exchanger

  14. Beam quality conversion factors for parallel-plate ionization chambers in MV photon beams

    SciTech Connect (OSTI)

    Muir, B. R.; McEwen, M. R.; Rogers, D. W. O. [Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada); Institute for National Measurement Standards, National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada); Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2012-03-15T23:59:59.000Z

    Purpose: To investigate the behavior of plane-parallel ion chambers in high-energy photon beams through measurements and Monte Carlo simulations. Methods: Ten plane-parallel ion chamber types were obtained from the major ion chamber manufacturers. Absorbed dose-to-water calibration coefficients are measured for these chambers and k{sub Q} factors are determined. In the process, the behaviors of the chambers are characterized through measurements of leakage currents, chamber settling in cobalt-60, polarity and ion recombination behavior, and long-term stability. Monte Carlo calculations of the absorbed dose to the air in the ion chamber and absorbed dose to water are obtained to calculate k{sub Q} factors. Systematic uncertainties in Monte Carlo calculated k{sub Q} factors are investigated by varying material properties and chamber dimensions. Results: Chamber behavior was variable in MV photon beams, especially with regard to chamber leakage and ion recombination. The plane-parallel chambers did not perform as well as cylindrical chambers. Significant differences up to 1.5% were observed in calibration coefficients after a period of eight months although k{sub Q} factors were consistent on average within 0.17%. Chamber-to-chamber variations in k{sub Q} factors for chambers of the same type were at the 0.2% level. Systematic uncertainties in Monte Carlo calculated k{sub Q} factors ranged between 0.34% and 0.50% depending on the chamber type. Average percent differences between measured and calculated k{sub Q} factors were - 0.02%, 0.18%, and - 0.16% for 6, 10, and 25 MV beams, respectively. Conclusions: Excellent agreement is observed on average at the 0.2% level between measured and Monte Carlo calculated k{sub Q} factors. Measurements indicate that the behavior of these chambers is not adequate for their use for reference dosimetry of high-energy photon beams without a more extensive QA program than currently used for cylindrical reference-class ion chambers.

  15. Shock-Dispersed-Fuel Charges: Combustion in Chambers and Tunnels

    SciTech Connect (OSTI)

    Neuwald, P; Reichenbach, H; Kuhl, A L

    2003-04-22T23:59:59.000Z

    In previous studies we have investigated after-burning effects of a fuel-rich explosive (TNT). In that case the detonation only releases about 30% of the available energy, but generates a hot cloud of fuel that can burn in the ambient air, thus evoking an additional energy release that is distributed in space and time. The current series of small-scale experiments can be looked upon as a natural generalization of this mechanism: a booster charge disperses a (non-explosive) fuel, provides mixing with air and, by means of the hot detonation products, the energy to ignite the fuel. The current version of our miniature Shock-Dispersed-Fuel (SDF) charges consists of a spherical booster charge of 0.5 g PETN, embedded in a paper cylinder of approximately 2.2 cm, which is filled with powdered fuel compositions. The main compositions studied up to now contain aluminum flakes, hydrocarbon powders like polyethylene or hexosen (sucrose) and/or carbon particles. These charges were studied in four different chambers: two cylindrical vessels of 6.6-1 and 40.5-1 volume with a height-to-diameter ratio of approximately 1, a rectangular chamber of 41 (10.5 x 10.5 x 38.6 cm) and a 299.6 cm long tunnel model with a cross section of 8 x 8 cm (volume 19.21) closed at both ends.

  16. Slag monitoring system for combustion chambers of steam boilers

    SciTech Connect (OSTI)

    Taler, J.; Taler, D. [Cracow University of Technology, Krakow (Poland)

    2009-07-01T23:59:59.000Z

    The computer-based boiler performance system presented in this article has been developed to provide a direct and quantitative assessment of furnace and convective surface cleanliness. Temperature, pressure, and flow measurements and gas analysis data are used to perform heat transfer analysis in the boiler furnace and evaporator. Power boiler efficiency is calculated using an indirect method. The on-line calculation of the exit flue gas temperature in a combustion chamber allows for an on-line heat flow rate determination, which is transferred to the boiler evaporator. Based on the energy balance for the boiler evaporator, the superheated steam mass flow rate is calculated taking into the account water flow rate in attemperators. Comparing the calculated and the measured superheated steam mass flow rate, the effectiveness of the combustion chamber water walls is determined in an on-line mode. Soot-blower sequencing can be optimized based on actual cleaning requirements rather than on fixed time cycles contributing to lowering of the medium usage in soot blowers and increasing of the water-wall lifetime.

  17. Atmospheric-pressure plasma decontamination/sterilization chamber

    DOE Patents [OSTI]

    Herrmann, Hans W. (Los Alamos, NM); Selwyn, Gary S. (Los Alamos, NM)

    2001-01-01T23:59:59.000Z

    An atmospheric-pressure plasma decontamination/sterilization chamber is described. The apparatus is useful for decontaminating sensitive equipment and materials, such as electronics, optics and national treasures, which have been contaminated with chemical and/or biological warfare agents, such as anthrax, mustard blistering agent, VX nerve gas, and the like. There is currently no acceptable procedure for decontaminating such equipment. The apparatus may also be used for sterilization in the medical and food industries. Items to be decontaminated or sterilized are supported inside the chamber. Reactive gases containing atomic and metastable oxygen species are generated by an atmospheric-pressure plasma discharge in a He/O.sub.2 mixture and directed into the region of these items resulting in chemical reaction between the reactive species and organic substances. This reaction typically kills and/or neutralizes the contamination without damaging most equipment and materials. The plasma gases are recirculated through a closed-loop system to minimize the loss of helium and the possibility of escape of aerosolized harmful substances.

  18. The dynamics of Kerguelen Plateau magma evolution: New insights from major element, trace element and Sr isotope microanalysis of plagioclase hosted in Elan

    E-Print Network [OSTI]

    Accepted 9 March 2009 Editor: D.B. Dingwell Keywords: Kerguelen Laser ablation Microanalysis Large igneous province Ocean Drilling Program The Kerguelen Plateau and Broken Ridge in the southern Indian Ocean. A scientific objective of Ocean Drilling Program (ODP) Leg 183 was to constrain the post-melting magma

  19. Finite element solution of Laplace's equation for ion-atom chambers Jacob Golde, Janine Shertzer, and Paul Oxley

    E-Print Network [OSTI]

    Oxley, Paul

    Finite element solution of Laplace's equation for ion-atom chambers Jacob Golde, Janine Shertzer for ion-atom chambers. We first consider a simplified model chamber for which an analytical solution can is carried out in an ion-atom chamber. The atomic beam first passes through a region of the cham- ber where

  20. Dose response of selected ion chambers in applied homogeneous transverse and longitudinal magnetic fields

    SciTech Connect (OSTI)

    Reynolds, M. [Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Fallone, B. G. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Departments of Oncology and Physics, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Rathee, S. [Department of Medical Physics, Cross Cancer Institute, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada); Department of Oncology, Medical Physics Division, University of Alberta, 11560 University Avenue, Edmonton, Alberta T6G 1Z2 (Canada)

    2013-04-15T23:59:59.000Z

    Purpose: The magnetic fields of an integrated MR-Linac system will alter the paths of electrons that produce ions in the ionization chambers. The dose response of selected ion chambers is evaluated in the presence of varying transverse and longitudinal magnetic fields. The investigation is useful in calibration of therapeutic x-ray beams associated with MR-Linac systems. Methods: The Monte Carlo code PENELOPE was used to model the irradiation of NE2571, and PR06C ionization chambers in the presence of a transverse and longitudinal (with respect to the photon beam) magnetic fields of varying magnitude. The long axis of each chamber was simulated both parallel and perpendicular to the incident photon beam for each magnetic field case. The dose deposited in each chamber for each case was compared to the case with zero magnetic field by means of a ratio. The PR06C chamber's response was measured in the presence of a transverse magnetic field with field strengths ranging from 0.0 to 0.2 T to compare to simulated results. Results: The simulations and measured data show that in the presence of a transverse magnetic field there is a considerable dose response (maximum of 11% near 1.0 T in the ion chambers investigated, which depends on the magnitude of magnetic field, and relative orientation of the magnetic field, radiation beam, and ion chamber. Measurements made with the PR06C chamber verify these results in the region of measurement. In contrast, a longitudinal magnetic field produces only a slight increase in dose response (2% at 1.5 T) that rises slowly with increasing magnetic field and is seemingly independent of chamber orientation. Response trends were similar for the two ion chambers and relative orientations considered, but slight variations are present from chamber to chamber. Conclusions: Care must be taken when making ion chamber measurements in a transverse magnetic field. Ion chamber responses vary not only with transverse field strength, but with chamber orientation and type, and can be considerable. Longitudinal magnetic fields influence ion chamber responses relatively little (2% at 1.5 T), and only at field strengths in excess of 1.0 T.

  1. Impact of unsteady flow processes on the performance of a high speed axial flow compressor

    E-Print Network [OSTI]

    Botros, Barbara Brenda

    2008-01-01T23:59:59.000Z

    This thesis examines the unsteady interactions between blade rows in a high Mach number, highly-loaded compressor stage. Two straight vane/rotor configurations with different axial spacing between vane and rotor are ...

  2. Determination of the ?(1232) axial and pseudoscalar form factors from lattice QCD

    E-Print Network [OSTI]

    Alexandrou, Constantia

    We present a lattice QCD calculation of the ?(1232) matrix elements of the axial-vector and pseudoscalar currents. The decomposition of these matrix elements into the appropriate Lorentz invariant form factors is carried ...

  3. Møller Energy-Momentum Complex for an Axially Symmetric Scalar Field

    E-Print Network [OSTI]

    I. Radinschi

    2002-03-25T23:59:59.000Z

    We calculate the energy-distribution for an axially symmetric scalar field in the M{\\o}ller prescription. The total energy is given by the parameter m of the space-time.

  4. On the solution of the static Maxwell system in axially symmetric inhomogeneous media

    E-Print Network [OSTI]

    Kira V. Khmelnytskaya; Vladislav V. Kravchenko; Hector Oviedo

    2007-04-11T23:59:59.000Z

    We consider the static Maxwell system with an axially symmetric dielectric permittivity and construct complete systems of its solutions which can be used for analytic and numerical solution of corresponding boundary value problems.

  5. Axially staggered seed-blanket reactor-fuel-module construction. [LWBR

    DOE Patents [OSTI]

    Cowell, G.K.; DiGuiseppe, C.P.

    1982-10-28T23:59:59.000Z

    A heterogeneous nuclear reactor of the seed-blanket type is provided wherein the fissile (seed) and fertile (blanket) nuclear fuels are segregated axially within each fuel element such that fissile and fertile regions occur in an alternating pattern along the length of the fuel element. Further, different axial stacking patterns are used for the fuel elements of at least two module types such that when modules of different types are positioned adjacent to one another, the fertile regions of the modules are offset or staggered. Thus, when a module of one type is surrounded by modules of the second type the fertile regions thereof will be surrounded on all sides by fissile material. This provides enhanced neutron communication both radially and axially, thereby resulting in greater power oscillation stability than other axial arrangements.

  6. A simple criterion for three-dimensional flow separation in axial compressors

    E-Print Network [OSTI]

    Lei, Vai-Man

    2006-01-01T23:59:59.000Z

    Most modem blade designs in axial-flow compressors diffuse the flow efficiently over 20% to 80% of blade span and it is the endwall regions that set the limits in compressor performance. This thesis addresses the estimation, ...

  7. Impact of unsteady secondary air flow interaction with main flow on loss generation in axial turbines

    E-Print Network [OSTI]

    Clifton, David (David Madison)

    2014-01-01T23:59:59.000Z

    Secondary air, often called purge air, is injected through the endwall gap between stationary vanes and rotating rotors in axial turbines to prevent ingestion of the hot working gas into the endwall cavities. Three-dimensional ...

  8. Performance characteristics of a low pressure cyclone for axial-flow fan exhausts

    E-Print Network [OSTI]

    Simpson, Shay Lynn

    1996-01-01T23:59:59.000Z

    on axial-flow fan exhausts to significantly reduce particulate emissions. Average emission concentrations, cut-point diameters, PMIO emission concentrations, and fractional efficiencies from this cyclone operating at different cyclone inlet velocities...

  9. Multi-axial fracture behaviour of notched carbon-fibre/epoxy laminates

    E-Print Network [OSTI]

    Tan, Julian Lip Yi

    2015-04-28T23:59:59.000Z

    conditions in structural systems such as aircrafts and automobiles has immensely motivated the development of controlled multi-axial and biaxial loading tests. According to Chen & Matthews (1993), two main types of specimens are used for combined loading...

  10. Effect of flow oscillations on axial energy transport in a porous material

    SciTech Connect (OSTI)

    Siegel, R. (NASA Lewis Research Center, Cleveland, OH (USA))

    1987-02-01T23:59:59.000Z

    It has been shown analytically and experimentally that flow oscillations of a fluid within a channel can enhance the axial transfer of energy. The transport arises from an axial gradient in fluid temperature resulting from having reservoirs at different temperatures at either end of the channel. The present analysis develops relations for axial energy diffusion in a porous medium with oscillating flow. In some devices, such as the Sterling engine, there are regenerators with oscillating flow. Axial transport in the regenerator provides an energy loss; hence it is desirable to determine what factors can limit this diffusion. A regenerator in the form of a porous medium is difficult to model since the flow is continually disrupted by the irregularities of the porous structure. The formulation here will employ an internal heat transfer coefficient that couples the fluid and solid temperatures. The final result shows how the diffusion depends on the magnitude of the heat transfer coefficient and the maximum fluid displacement.

  11. The effect of nonuniform axial heat flux distribution on the critical heat flux

    E-Print Network [OSTI]

    Todreas, Neil E.

    1965-01-01T23:59:59.000Z

    A systematic experimental and analytic investigation of the effect of nonuniform axial heat flux distribution on critical heat rilux was performed with water in the quality condition. Utilizing a model which ascribes the ...

  12. Additives That Prevent Or Reverse Cathode Aging In Drift Chambers With Helium-Isobutane Gas

    E-Print Network [OSTI]

    Adam Boyarski

    2001-12-11T23:59:59.000Z

    Noise and Malter breakdown have been studied at high rates in a test chamber having the same cell structure and gas as in the BaBar drift chamber. The chamber was first damaged by exposing it to a high source level at an elevated high voltage, until its operating current at normal voltages was below 0.5nA/cm. Additives such as water or alcohol allowed the damaged chamber to operate at 25 nA/cm, but when the additive was removed the operating point reverted to the original low value. However with 0.02% to 0.05% oxygen or 5% carbon dioxide the chamber could operate at more than 25 nA/cm, and continued to operate at this level even after the additive was removed. This shows for the first time that running with an O2 or CO2 additive at high ionisation levels can cure a damaged chamber from breakdown problems.

  13. Relativistic Hartree-Fock-Bogoliubov Theory With Density Dependent Meson Couplings in Axial Symmetry

    SciTech Connect (OSTI)

    Ebran, J.-P.; Khan, E.; Arteaga, D. Pena; Grasso, M. [Institut de Physique Nucleaire, 15 rue Georges Clemenceau 91406 Orsay Cedex (France); Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb, 10 000 Zagreb (Croatia)

    2009-08-26T23:59:59.000Z

    Most nuclei on the nuclear chart are deformed, and the development of new RIB facilities allows the study of exotic nuclei near the drip lines where a successful theoretical description requires both realistic pairing and deformation approaches. Relativistic Hartree-Fock-Bogoliubov model taking into account axial deformation and pairing correlations is introduced. Preliminary illustrative results with density dependent meson-nucleon couplings in axial symmetry will be discussed.

  14. Electron Diamagnetic Effect on Axial Force in an Expanding Plasma: Experiments and Theory

    SciTech Connect (OSTI)

    Takahashi, Kazunori [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Department of Electrical Engineering and Computer Science, Iwate University, Morioka 020-8551 (Japan); Lafleur, Trevor; Charles, Christine; Alexander, Peter; Boswell, Rod W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

    2011-12-02T23:59:59.000Z

    The axial force imparted from a magnetically expanding current-free plasma is directly measured for three different experimental configurations and compared with a two-dimensional fluid theory. The force component solely resulting from the expanding field is directly measured and identified as an axial force produced by the azimuthal current due to an electron diamagnetic drift and the radial component of the magnetic field. The experimentally measured forces are well described by the theory.

  15. Liquid fuel vaporizer and combustion chamber having an adjustable thermal conductor

    DOE Patents [OSTI]

    Powell, Michael R; Whyatt, Greg A; Howe, Daniel T; Fountain, Matthew S

    2014-03-04T23:59:59.000Z

    The efficiency and effectiveness of apparatuses for vaporizing and combusting liquid fuel can be improved using thermal conductors. For example, an apparatus having a liquid fuel vaporizer and a combustion chamber can be characterized by a thermal conductor that conducts heat from the combustion chamber to the vaporizer. The thermal conductor can be a movable member positioned at an insertion depth within the combustion chamber that corresponds to a rate of heat conduction from the combustion chamber to the vaporizer. The rate of heat conduction can, therefore, be adjusted by positioning the movable member at a different insertion depth.

  16. TEST OF A LIQUID ARGON CHAMBER WITH 20-u m RMS RESOLUTION

    E-Print Network [OSTI]

    Derenzo, S.E.; Kirschbaum, A.R.; Eberhard, P.H.; Ross, R.R.; Sclmitz, F.T.

    2008-01-01T23:59:59.000Z

    electronics to build chambers with spacings of , "'rJ about 40 fJ-m to increase the signal to noise and hence reliability

  17. Charge-Focusing Readout of Time Projection Chambers

    E-Print Network [OSTI]

    S. J. Ross; M. T. Hedges; I. Jaegle; M. D. Rosen; I. S. Seong; T. N. Thorpe; S. E. Vahsen; J. Yamaoka

    2013-04-02T23:59:59.000Z

    Time projection chambers (TPCs) have found a wide range of applications in particle physics, nuclear physics, and homeland security. For TPCs with high-resolution readout, the readout electronics often dominate the price of the final detector. We have developed a novel method which could be used to build large-scale detectors while limiting the necessary readout area. By focusing the drift charge with static electric fields, we would allow a small area of electronics to be sensitive to particle detection for a much larger detector volume. The resulting cost reduction could be important in areas of research which demand large-scale detectors, including dark matter searches and detection of special nuclear material. We present simulations made using the software package Garfield of a focusing structure to be used with a prototype TPC with pixel readout. This design should enable significant focusing while retaining directional sensitivity to incoming particles. We also present first experimental results and compare them with simulation.

  18. Conceptual Design Report for the Extreme Ecosystems Test Chambers

    SciTech Connect (OSTI)

    C. Barnes; J. Beller; K. Caldwell; K. Croft; R. Cherry; W. Landman

    1998-12-01T23:59:59.000Z

    This conceptual design supports the creation of Extreme Ecosystems Test Chambers, which will replicate deep subsurface and subocean environments characterized by high pressure (2,000 psi) and subfreezing to high temperature (-4 to 300 degrees F) with differing chemical and saturation conditions. The design provides a system to support research and development that includes heat transfer, phase change issues in porous media, microbiology in extreme environments, and carbon sequestration and extraction. The initial system design is based on the research needs to support the commercial production of methane hydrates from subsurface sediments. The design provides for three pressure vessels: a Down Hole Test Vessel, a Vertical Multi-phase Test Vessel, and a Horizontal Multi-phase Test Vessel.

  19. Beam Measurements of a CLOUD (Cosmics Leaving OUtdoor Droplets) Chamber

    E-Print Network [OSTI]

    Kirkby, Jasper

    2001-01-01T23:59:59.000Z

    A striking correlation has recently been observed between global cloud cover and the flux of incident cosmic rays. The effect of natural variations in the cosmic ray flux is large, causing estimated changes in the Earth's energy radiation balance that are comparable to those attributed to greenhouse gases from the burning of fossil fuels since the Industrial Revolution. However a direct link between cosmic rays and cloud formation has not been unambiguously established. We therefore propose to experimentally measure cloud (water droplet) formation under controlled conditions in a test beam at CERN with a CLOUD chamber, duplicating the conditions prevailing in the troposphere. These data, which have never been previously obtained, will allow a detailed understanding of the possible effects of cosmic rays on clouds and confirm, or otherwise, a direct link between cosmic rays, global cloud cover and the Earth's climate. The measurements will, in turn, allow more reliable calculations to be made of the residual e...

  20. Simulation of Enhanced-Explosive Devices in Chambers and Tunnels

    SciTech Connect (OSTI)

    Bell, J B; Kuhl, A L; Beckner, V E

    2007-06-05T23:59:59.000Z

    Introduction: Shock-dispersed fuel (SDF) explosives use a small chemical charge to disperse a combustible fuel that burns in the post-detonation environment. The energy released in the combustion process has the potential for generating higher pressures and temperatures than conventional explosives. However, the development of these types of novel explosive systems requires a detailed understanding of all of the modes of energy release. Objective: The objective of this project is develop a simulation capability for predicting explosion and combustion phase of SDF charges and apply that capability to quantifying the behavior of these types of explosives. Methodology: We approximate the dynamics of an SDF charge using high Reynolds number, fast chemistry model that effectively captures the thermodynamic behavior of SDF charges and accurately models the key modes of energy release. The overall computational model is combined with Adaptive Mesh Refinement (AMR) , implemented in a parallel adaptive framework suited to the massively parallel computer systems. Results: We have developed a multiphase version of the model and used it to simulate an SDF charge in which the dispersed fuel is aluminum flakes. Flow visualizations show that the combustion field is turbulent for the chamber and tunnel cases studied. During the 3 milli-seconds of simulation, over 90% of the Al fuel was consumed for the chamber case, while about 40% was consumed in the tunnel case in agreement with Al-SDF experiments. Significance to DoD: DoD has a requirement to develop enhanced energetic materials to support future military systems. The SDF charges described here utilize the combustion mechanism to increase energy per gram of fuel by a factor of 7 to 10 over conventional (detonating) charges, and increase the temperature of the explosion cloud to 2,000-4,000 K (depending on the SDF fuel). Accurate numerical simulation of such SDF explosions allows one to understand the energy release mechanism, and thereby design full-scale systems with greatly improved explosive efficiency.

  1. Method and apparatus for active control of combustion rate through modulation of heat transfer from the combustion chamber wall

    DOE Patents [OSTI]

    Roberts, Jr., Charles E.; Chadwell, Christopher J.

    2004-09-21T23:59:59.000Z

    The flame propagation rate resulting from a combustion event in the combustion chamber of an internal combustion engine is controlled by modulation of the heat transfer from the combustion flame to the combustion chamber walls. In one embodiment, heat transfer from the combustion flame to the combustion chamber walls is mechanically modulated by a movable member that is inserted into, or withdrawn from, the combustion chamber thereby changing the shape of the combustion chamber and the combustion chamber wall surface area. In another embodiment, heat transfer from the combustion flame to the combustion chamber walls is modulated by cooling the surface of a portion of the combustion chamber wall that is in close proximity to the area of the combustion chamber where flame speed control is desired.

  2. ANALYSIS OF THE AXIAL GAP VS FIBERBOARD MOISTURE CONTENT IN A 9975 SHIPPING PACKAGE

    SciTech Connect (OSTI)

    Daugherty, W.

    2013-09-30T23:59:59.000Z

    The fiberboard assembly within a 9975 shipping package contains a modest amount of moisture, which can migrate to the cooler regions of the package when an internal heat load is present. Typically, this leads to increased moisture levels in the bottom fiberboard layers, along with elevated chloride levels which can leach from the fiberboard. Concerns have been raised that this condition could lead to corrosion of the stainless steel drum. It has been postulated that checking the axial gap at the top of the package against the current 1 inch maximum criterion provides a sufficient indication regarding the integrity of the fiberboard and drum. This report estimates the increase in axial gap that might be expected for a given moisture increase in the bottom fiberboard layers, and the likelihood that the increase will create a nonconforming condition that will lead to identification of the moisture increase. Using data relating the fiberboard moisture content with the degree of compaction under load, the present analysis indicates that the axial gap will increase by 0.282 inch as the bottom fiberboard layers approach the saturation point. This increase will cause approximately 58% of packages with otherwise nominal package component dimensions to fail the axial gap criterion, based on a survey of axial gap values recorded in K-Area surveillance activities. As the moisture content increases above saturation, the predicted increase in axial gap jumps to 0.405 inch, which would result in 92% or more of all packages failing the axial gap criterion. The data and analysis described in this report are specific to cane fiberboard. While it is expected that softwood fiberboard will behave similarly, such behavior has not yet been demonstrated.

  3. IFE CHAMBER TECHNOLOGY STATUS AND FUTURE CHALLENGES W.R. Meier1

    E-Print Network [OSTI]

    Raffray, A. René

    1 IFE CHAMBER TECHNOLOGY ­ STATUS AND FUTURE CHALLENGES W.R. Meier1 , A.R. Raffrary2 , S.I. Abdel.gov (925) 422-8536 2. University of California, San Diego, CA 3. Georgia Institute of Technology, Atlanta-ion, laser and Z-pinch drivers. A variety of chamber concepts are being investigated including dry- wall

  4. IFE CHAMBER TECHNOLOGY STATUS AND FUTURE CHALLENGES W.R. Meier1

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    IFE CHAMBER TECHNOLOGY ­ STATUS AND FUTURE CHALLENGES W.R. Meier1 , A.R. Raffray2 , S.I. Abdel.gov (925) 422-8536 2. University of California, San Diego, CA 3. Georgia Institute of Technology, Atlanta-ion, laser and Z-pinch drivers. A variety of chamber concepts are being investigated including dry- wall

  5. The development and application of advanced analytical methods to commercial ICF reactor chambers. Final report

    SciTech Connect (OSTI)

    Cousseau, P.; Engelstad, R.; Henderson, D.L. [and others

    1997-10-01T23:59:59.000Z

    Progress is summarized in this report for each of the following tasks: (1) multi-dimensional radiation hydrodynamics computer code development; (2) 2D radiation-hydrodynamic code development; (3) ALARA: analytic and Laplacian adaptive radioactivity analysis -- a complete package for analysis of induced activation; (4) structural dynamics modeling of ICF reactor chambers; and (5) analysis of self-consistent target chamber clearing.

  6. Plasma Chamber and APEX Budget Plans for FY 2000 (and FY 2001)

    E-Print Network [OSTI]

    Abdou, Mohamed

    Plasma Chamber and APEX Budget Plans for FY 2000 (and FY 2001) Spokesperson: Mohamed Abdou OFES: Plasma Chamber Spokesperson: M. Abdou Part I: VLT Director's Proposed Budget: $2200K Task Description Plans and Budgets Technology Area: APEX Spokesperson: M. Abdou Part I: VLT Director's Proposed Budget

  7. In situ reduction and evaluation of anode supported single chamber solid oxide fuel cells

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    In situ reduction and evaluation of anode supported single chamber solid oxide fuel cells D.05.118 #12;Abstract Single chamber anode-supported fuel cells are investigated under several methane under methane-to-oxygen ratio (Rmix) of 2. Anode-supported fuel cells are investigated regarding

  8. Combustion in Meso-scale Vortex Chambers Ming-hsun Wu*

    E-Print Network [OSTI]

    Yang, Vigor

    1 Combustion in Meso-scale Vortex Chambers Ming-hsun Wu* , Yanxing Wang, Vigor Yang and Richard A) #12;2 COMBUSTION IN MESO-SCALE VORTEX CHAMBERS Ming-hsun Wu, Yanxing Wang, Vigor Yang and Richard A with the chemical energy varying from 25 to 174W. For the largest combustion volume, hydrogen and hydrocarbons

  9. A simple analytical model to study and control azimuthal instabilities in annular combustion chambers

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    A simple analytical model to study and control azimuthal instabilities in annular combustion analytical method to compute the azimuthal modes appearing in annular combustion chambers and help analyzing exper- imental, acoustic and LES (Large Eddy Simulation) data obtained in these combustion chambers

  10. A time dependent solution for the operation of ion chambers in a high ionization background

    E-Print Network [OSTI]

    Christos Velissaris

    2005-01-17T23:59:59.000Z

    We have derived a time dependent solution describing the development of space charge inside an ion chamber subjected to an externally caused ionization rate N. The solution enables the derivation of a formula that the operational parameters of the chamber must satisfy for saturation free operation. This formula contains a correction factor to account for the finite duration of the ionization rate N.

  11. Analytical and numerical studies of heavy ion beam transport in the fusion chamber

    E-Print Network [OSTI]

    Kaganovich, Igor

    Analytical and numerical studies of heavy ion beam transport in the fusion chamber IGOR D to acceptable levels. During ion beam propagation in the chamber, electrons are drawn into the beam, Princeton, New Jersey 08543, USA Abstract The propagation of a high-current finite-length ion charge bunch

  12. Simulation of Gas Dynamic Behavior in Dry-Wall Inertial Fusion Energy Chambers

    E-Print Network [OSTI]

    Tillack, Mark

    . In this work, the code TSUNAMI [2] was used to model chamber gas dynamics for different shapes, sizes of size scaling. Previous- ly, TSUNAMI was used primarily for studying liquid protec- ted chambers which the basic response charac- teristics (with emphasis on the evolution towards a quiescent state

  13. Vapor chambers with jumping-drop liquid return from superhydrophobic condensers

    E-Print Network [OSTI]

    Chen, Chuan-Hua

    Vapor chambers with jumping-drop liquid return from superhydrophobic condensers Jonathan B. Boreyko January 2013 Accepted 28 January 2013 Keywords: Jumping drops Vapor chamber Superhydrophobicity Wick-propelled jumping drops on a superhydrophobic condenser offer a new mechanism to return the working fluid

  14. Seismic Evidence For A Hydrothermal Layer Above The Solid Roof Of The Axial

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-f < RAPID‎ |Rippey JumpAir Jump to:ScottsSearchSt. Louis,SeeoMagma

  15. Beam Measurements of a CLOUD (Cosmics Leaving OUtdoor Droplets) Chamber

    E-Print Network [OSTI]

    Jasper Kirkby

    2001-04-27T23:59:59.000Z

    A striking correlation has recently been observed between global cloud cover and the flux of incident cosmic rays. The effect of natural variations in the cosmic ray flux is large, causing estimated changes in the Earth's energy radiation balance that are comparable to those attributed to greenhouse gases from the burning of fossil fuels since the Industrial Revolution. However a direct link between cosmic rays and cloud formation has not been unambiguously established. We therefore propose to experimentally measure cloud (water droplet) formation under controlled conditions in a test beam at CERN with a CLOUD chamber, duplicating the conditions prevailing in the troposphere. These data, which have never been previously obtained, will allow a detailed understanding of the possible effects of cosmic rays on clouds and confirm, or otherwise, a direct link between cosmic rays, global cloud cover and the Earth's climate. The measurements will, in turn, allow more reliable calculations to be made of the residual effect on global temperatures of the burning of fossil fuels, an issue of profound importance to society. Furthermore, light radio-isotope records indicate a correlation has existed between global climate and the cosmic ray flux extending back over the present inter-glacial and perhaps earlier. This suggests it may eventually become possible to make long-term (10-1,000 year) predictions of changes in the Earth's climate, provided a deeper understanding can be achieved of the ``geomagnetic climate'' of the Sun and Earth that modulates the cosmic-ray flux.

  16. Effect of Axial Loading on Quench Performance in Nb3Sn Magnets

    SciTech Connect (OSTI)

    Ambrosio, G.; Bordini, B.; Caspi, S.; Dietderich, D.R.; Felice, H.; Hafalia, A.R.; Hannaford, C.R.; Lizarazo, J.; Lietzke, A.F.; McInturff, A.D.; Sabbi, G.L.; DiMarco, J.D.; Tartaglia, M.; Vedrice, P.; Ferracin, P.

    2008-06-01T23:59:59.000Z

    A series of tests has been performed at Lawrence Berkeley National Laboratory (LBNL) and Fermi National Accelerator Laboratory (FNAL) with the goal of assessing the influence of coil axial pre-load on Nb{sub 3}Sn magnet training. The tests involved two subscale Nb{sub 3}Sn magnets: SQ02, a quadrupole magnet fabricated as part of the US LHC Accelerator Research Program (LARP), and SD01, a dipole magnet developed in collaboration between CEA/Saclay and LBNL. Both magnets used similar Nb{sub 3}Sn flat racetrack coils from LBNL Subscale Magnet Program, and implemented an axial support system composed of stainless steel end-plates and aluminum rods. The system was designed to withstand full longitudinal electro-magnetic forces and provide controllable preloads. Quench performances, training, and quench locations have been recorded in various axial loading conditions. Test results are reported.

  17. Flexural support member having a high ratio of lateral-to-axial stiffness

    DOE Patents [OSTI]

    Haas, W.M.B.

    1983-06-23T23:59:59.000Z

    A convoluted flexible support structure is provided which is capable of supplying a lateral to axial spring rate in excess of 1000 to 1. A support member in the form of a steel disc having a specified number of rather large radius, concentric convolutions and a thickness in the range of from about 0.01 to 0.02 inch has an axial stiffness of about 50 pounds/inch while the lateral stiffness is about 100,000 pounds/inch. The support member may be used to support a vibration device where the lateral motion of the vibrator must be highly restricted while providing relatively free axial displacement of about +-0.25 inch.

  18. Axial seal system for a gas turbine steam-cooled rotor

    DOE Patents [OSTI]

    Mashey, Thomas Charles (Anderson, SC)

    2002-01-01T23:59:59.000Z

    An axial seal assembly is provided at the interface between adjacent wheels and spacers of a gas turbine rotor and disposed about tubes passing through openings in the rotor adjacent the rotor rim and carrying a thermal medium. Each seal assembly includes a support bushing for supporting a land of the thermal medium carrying tube, an axially registering seat bushing disposed in the opposed opening and a frustoconical seal between the seal bushing and seat. The seal bushing includes a radial flange having an annular recess for retaining the outer diameter edge of the seal, while the seat bushing has an axially facing annular surface forming a seat for engagement by the inner diameter edge of the seal.

  19. Production of low axial energy spread ion beams with multicusp sources

    SciTech Connect (OSTI)

    Lee, Y.H.Y. [Univ. of California, Berkeley, CA (United States)

    1998-05-01T23:59:59.000Z

    Multicusp ion sources are capable of producing ions with low axial energy spread which are necessary in applications such as: ion projection lithography (IPL) and focused ion beams for the next generation lithographic tools and nuclear science experiments such as radioactive ion beam production. The axial ion energy spread for multicusp source is approximately 6 eV which is too large for IPL and radioactive ion beam applications. The addition of a magnetic filter which consists of a pair of permanent magnets to the multicusp source reduces the energy spread considerably. The reduction is due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. Axial ion energy spread of the filament driven ion source has been measured using three different techniques. In all cases, it was found to be less than 2 eV. Energy spread of the radio frequency (RF) driven source has also been explored, and it was found to be less than 3 eV with the proper RF-shielding. A new multicusp source configuration has been designed and constructed to further reduce the energy spread. To achieve a more uniform axial plasma potential distribution, a cylindrical magnetic filter has been designed and constructed for a 2-cm-diameter source. This new source configuration, the co-axial source, is new in its kind. The energy spread in this source has been measured to be a record low of 0.6 eV. Because of the novelty of this device, some plasma parameters inside the source have been studied. Langmuir probe has been used to measure the plasma potential, the electron temperature and the density distribution.

  20. Cardy-Verlinde formula for an axially symmetric dilaton-axion black hole

    E-Print Network [OSTI]

    Mubasher Jamil; M. Akbar; M. R. Setare

    2011-05-30T23:59:59.000Z

    It is shown that the Bekenstein-Hawking entropy of an axially symmetric dilaton-axion black hole can be expressed as a Cardy-Verlinde formula. By utilizing the first order quantum correction in the Bekenstein-Hawking entropy we find the modified expressions for the Casimir energy and pure extensive energy. The first order correction to the Cardy-Verlinde formula in the context of axially symmetric dilaton-axion black hole are obtained with the use of modified Casimir and pure extensive energies.

  1. Note: Simultaneous measurement of transverse speed and axial velocity from a single optical beam

    SciTech Connect (OSTI)

    Moro, Erik A.; Briggs, Matthew E. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2013-01-15T23:59:59.000Z

    A method is introduced for simultaneously measuring transverse speed and axial velocity using a single optical beam and a standard photon Doppler velocimetry (PDV) sensing architecture. This result is of particular interest given the recent, widespread use of PDV and the fact that optical velocimetry has thus far been limited to measuring motion in one dimension per probe. Further, this result demonstrates that both axial velocity data and transverse speed data (at least qualitative) may be obtained entirely through signal analysis; not requiring hardware modification. This result is immediately relevant to analyses of existing PDV data and to future efforts in high-speed optical velocimetry.

  2. An axially propagating two-stream instability in the Hall thruster plasma

    SciTech Connect (OSTI)

    Tsikata, S., E-mail: sedina.tsikata@cnrs-orleans.fr [ICARE, CNRS (UPR 3021), 1C ave. de la Recherche Scientifique, 45071 Orléans (France); Cavalier, J. [Institute of Plasma Physics ASCR, Prague (Czech Republic); Héron, A. [CPHT, CNRS (UMR 7644), Ecole Polytechnique, Route de Saclay, 91128 Palaiseau (France); Honoré, C.; Grésillon, D. [LPP, CNRS (UMR 7648), Ecole Polytechnique-Univ. Paris-Sud-UPMC Univ. Paris 06, Route de Saclay, 91128 Palaiseau (France); Lemoine, N.; Coulette, D. [IJL, CNRS (UMR 7198), Université de Lorraine, BP 70239, 54506 Vandoeuvre-lès-Nancy (France)

    2014-07-15T23:59:59.000Z

    Collective Thomson scattering experiments reveal the presence of high-frequency, axial electron density fluctuations at millimetric wavelengths in the Hall thruster plasma. The properties of these fluctuations are investigated experimentally and via linear kinetic theory. The relative drift of electrons and ions in the axial direction is found to be insufficient to cause excitation of the observed mode. Instead, the mode is determined to be a two-stream instability arising due to the velocity difference between singly and doubly charged ion populations in the plume.

  3. The plasma properties and electron emission characteristics of near-zero differential resistance of hollow cathode-based plasma contactors with a discharge chamber

    SciTech Connect (OSTI)

    Xie, Kan, E-mail: xiekan@bit.edu.cn [School of Aerospace Engineering, Beijing Institute of Technology, Beijing 100081 (China); Farnell, Casey C.; Williams, John D. [Department of Mechanical Engineering, Colorado State University, Fort Collins, Colorado 80524 (United States)

    2014-08-15T23:59:59.000Z

    The formation of electron emission-bias voltage (I-V) characteristics of near-zero differential resistance in the cathodic plasma contactor for bare electrodynamic tether applications, based on a hollow cathode embedded in a ring-cusp ionization stage, is studied. The existence of such an I-V regime is important to achieve low impedance performance without being affected by the space plasma properties for a cathodic plasma contactor. Experimental data on the plasma structure and properties downstream from the ionization stage are presented as functions of the xenon flow rate and the electron emission current. The electrons were emitted from the cathode to the cylindrical vacuum chamber wall (r?=?0.9?m) under ?10{sup ?5?}Torr of vacuum pressure. The ring-cusp configuration selected for the plasma contactor created a 125-Gauss axial field near the cathode orifice, along with a large-volume 50-Gauss magnitude pocket in the stage. A baseline ion energy cost of ?300?eV/ion was measured in the ionization stage when no electrons were emitted to the vacuum chamber wall. In addition, the anode fall growth limited the maximum propellant unitization to below ?75% in the discharge loss curves for this ion stage. Detailed measurements on the plasma properties were carried out for the no-electron emission and 3?A emission conditions. The experimental data are compared with 1-D models, and the effectiveness of the model is discussed. The four key issues that played important roles in the process of building the near-zero different resistance I-V regime are: a significant amount of ionization by the emission electrons, a decrease in the number of reflected electrons in the plume, the electron-temperature increment, and low initial ion energy at the source outlet.

  4. IFE chamber dry wall materials response to pulsed X-rays and ions at power-plant level fluences

    E-Print Network [OSTI]

    Raffray, A. René

    IFE chamber dry wall materials response to pulsed X-rays and ions at power-plant level fluences T initiated to test IFE chamber wall materials response to X-rays on the Z facility, and to ions on RHEPP-1 a collaborative investigation of the response of candidate first-wall inertial fusion energy (IFE) reactor chamber

  5. Synthesis, structural characterization and properties of aluminum (III) meso-tetraphenylporphyrin complexes axially

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    ) complexes axially bonded to phosphinate anions and present their properties as supramolecular building free base (H2TPP) as starting material (Figure 1). H2TPP was treated with AlMe3 and the phosphinic acid in high yield (85-87%). Figure 2. X-ray structure of [1.EtOH] supramolecular chains. Light gray, C

  6. New Structural Model for Multicomponent Pile Cross Sections under Axial Load

    E-Print Network [OSTI]

    Horvath, John S.

    New Structural Model for Multicomponent Pile Cross Sections under Axial Load John S. Horvath, Ph.D., P.E., M.ASCE1 Abstract: Piles composed of more than one material in their cross section have been used for more than 100 years. Originally this was limited to driven steel shell or pipe piles filled

  7. MOISTURE EFFECT ON DURABILITY OF AXIALLY LOADED CONCRETE-FILLED TUBULAR FRP PILES

    E-Print Network [OSTI]

    MOISTURE EFFECT ON DURABILITY OF AXIALLY LOADED CONCRETE-FILLED TUBULAR FRP PILES Miguel Pando, Ph_rizkalla@ncsu.edu ABSTRACT Fiber reinforced polymer (FRP) composite piles are a possible foundation alternative for projects located in harsh marine environments. Problems associated with traditional pile materials used in harsh

  8. Cost effective combined axial fan and throttling valve control of ventilation rate

    E-Print Network [OSTI]

    Sengun, Mehmet Haluk

    Cost effective combined axial fan and throttling valve control of ventilation rate C.J. Taylor 1 P with Proportional-Integral-Plus (PIP) control of ventilation rate in mechanically ventilated agricultural buildings ventilation. The new combined fan/valve configuration is compared with a commercially available PID

  9. Single pulse ultrafast laser imprinting of axial dot arrays in bulk glasses C. Mauclair,1,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Single pulse ultrafast laser imprinting of axial dot arrays in bulk glasses C. Mauclair,1, A sam- ples were irradiated with 160 fs pulses from an 800 nm Ti:Sapphire amplified ultrafast laser.mauclair@univ-st-etienne.fr Compiled December 20, 2010 Ultrafast laser processing of bulk transparent materials can significantly gain

  10. Axial and radial preliminary results of the neutron radiation from miniature plasma focus devices.

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Axial and radial preliminary results of the neutron radiation from miniature plasma focus devices. Introduction. The plasma focus (PF) is a dense transient plasma source of high temperature, when it operate of understanding the physics related to the plasma focus working at this limit of unexplored energy, b) to develop

  11. Gravitational waves from a test particle scattered by a neutron star: Axial mode case

    E-Print Network [OSTI]

    Kazuhiro Tominaga; Motoyuki Saijo; Kei-ichi Maeda

    1999-09-20T23:59:59.000Z

    Using a metric perturbation method, we study gravitational waves from a test particle scattered by a spherically symmetric relativistic star. We calculate the energy spectrum and the waveform of gravitational waves for axial modes. Since metric perturbations in axial modes do not couple to the matter fluid of the star, emitted waves for a normal neutron star show only one peak in the spectrum, which corresponds to the orbital frequency at the turning point, where the gravitational field is strongest. However, for an ultracompact star (the radius $R \\lesssim 3M$), another type of resonant periodic peak appears in the spectrum. This is just because of an excitation by a scattered particle of axial quasinormal modes, which were found by Chandrasekhar and Ferrari. This excitation comes from the existence of the potential minimum inside of a star. We also find for an ultracompact star many small periodic peaks at the frequency region beyond the maximum of the potential, which would be due to a resonance of two waves reflected by two potential barriers (Regge-Wheeler type and one at the center of the star). Such resonant peaks appear neither for a normal neutron star nor for a Schwarzschild black hole. Consequently, even if we analyze the energy spectrum of gravitational waves only for axial modes, it would be possible to distinguish between an ultracompact star and a normal neutron star (or a Schwarzschild black hole).

  12. Earth Planets Space, 64, 113120, 2012 Upper ionosphere of Mars is not axially symmetrical

    E-Print Network [OSTI]

    Gurnett, Donald A.

    Earth Planets Space, 64, 113­120, 2012 Upper ionosphere of Mars is not axially symmetrical E to the ionosphere providing momentum and energy transfer to the upper layers of the ionospheric plasma. While dependence rather closely follow the Chapman model (Gurnett et al., 2008; Morgan et al., 2008; Withers, 2009

  13. Optimization of a Microscale, Axial-Flux, Permanent-Magnet Generator D. P. Arnold1*

    E-Print Network [OSTI]

    -phase, axial- flux, PM machine, consisting of a stator with Cu surface windings and a multi-pole SmCo PM rotor of the overall machine geometry and stator winding patterns. 2. MACHINE OVERVIEW The generator is a three back iron and a stator with Cu surface windings on a magnetically soft substrate, which serves

  14. Influence of constraints on axial growth reduction of cylindrical Li-ion battery electrode particles

    E-Print Network [OSTI]

    Jeevanjyoti Chakraborty; Colin P. Please; Alain Goriely; S. Jonathan Chapman

    2014-11-24T23:59:59.000Z

    Volumetric expansion of silicon anode particles in a lithium-ion battery during charging may lead to the generation of undesirable internal stresses. For a cylindrical particle such growth may also lead to failure by buckling if the expansion is constrained in the axial direction due to other particles or supporting structures. To mitigate this problem, the possibility of reducing axial growth is investigated theoretically by studying simple modifications of the solid cylinder geometry. First, an annular cylinder is considered with lithiation either from the inside or from the outside. In both cases, the reduction of axial growth is not found to be significant. Next, explicit physical constraints are studied by addition of a non-growing elasto-plastic material: first, an outer annular constraint on a solid silicon cylinder, and second a rod-like inner constraint for an annular silicon cylinder. In both cases, it is found that axial growth can be reduced if the yield stress of the constraining material is significantly higher than that of silicon and/or the thickness of the constraint is relatively high. Phase diagrams are presented for both the outer and the inner constraint cases to identify desirable operating zones. Finally, to interpret the phase diagrams and isolate the key physical principles two different simplified models are presented and are shown to recover important qualitative trends of the numerical simulation results.

  15. Tip clearance flows in axial compressors: stall inception and stability enhancement

    E-Print Network [OSTI]

    Weichert, Stephanie April

    2012-02-07T23:59:59.000Z

    The flow in the rotor tip clearance gap in an axial compressor influences the loss levels and the stall onset point. The role of tip clearance flows in the stall inception process is still debated, though. The aim of this thesis is to improve...

  16. Investigation of Non-synchronous Vibration Mechanism for a High Speed Axial Compressor Using Delayed DES

    E-Print Network [OSTI]

    Zha, Gecheng

    Investigation of Non-synchronous Vibration Mechanism for a High Speed Axial Compressor Using compressor. DDES is a hybrid model for turbulence simulation, which uses RANS model within the wall boundary of the compressor occurs due to the rotating flow instability in the vicinity of the rotor tip at a stable operation

  17. Instability inside a rotating gas cylinder subject to axial periodic strain Y. Duguet,a

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    of viscous flow inside a closed circular cylinder rotating about its axis, periodically compressed by meansInstability inside a rotating gas cylinder subject to axial periodic strain Y. Duguet,a J. F. Scott are known to support inertial oscillations whose frequencies are less than twice the basic rotation rate.1

  18. Non-Axial Octupole Deformations and Tetrahedral Symmetry in Heavy Nuclei

    SciTech Connect (OSTI)

    Mazurek, Katarzyna [Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Cracow (Poland); Dudek, Jerzy [Institut de Recherches Subatomiques, F-67037 Strasbourg Cedex 2 (France); Universite Louis Pasteur, F-67037 Strasbourg Cedex 2 (France)

    2005-11-21T23:59:59.000Z

    The total energies of about 120 nuclei in the Thorium region have been calculated within the macroscopic-microscopic method in the 5-dimensional space of deformation parameters {alpha}20, {alpha}22, {alpha}30, {alpha}32 and {alpha}40. The macroscopic energy term contains the nuclear surface-curvature dependence as proposed within the LSD approach. The microscopic energies are calculated with the Woods-Saxon single particle potential employing the universal set of parameters.We study a possible presence of the octupole axial and non-axial degrees of freedom all-over in the ({beta}, {gamma})-plane focussing on the ground-states, secondary minima and in the saddle points. In fact, a competition between axial and tri-axial octupole deformation parameters is obtained at the saddle points and in the secondary minima for many isotones with N > 136. The presence of the tetrahedral symmetry minima is predicted in numerous nuclei in the discussed region, although most of the time at relatively high excitation energies.

  19. VASCONCELOS, BARRETO: RELATIVE POSE BETWEEN AXIAL CAMERAS 1 Towards a minimal solution for the relative

    E-Print Network [OSTI]

    Barreto, Joao

    is central iff all the back-projection rays intersect in a single point in 3D, that is the viewpoint in 3D (the axis). The axial camera can be used to model vision systems and imaging situations of practical interest. Examples include any catadioptric system that combines a revolution mirror

  20. Nucleon axial charge from quenched lattice QCD with domain wall fermions

    E-Print Network [OSTI]

    Shoichi Sasaki; Kostas Orginos; Shigemi Ohta; Tom Blum; for the RBCK Collaboration

    2003-07-18T23:59:59.000Z

    We present a quenched lattice calculation of the nucleon isovector vector and axial-vector charges gV and gA. The chiral symmetry of domain wall fermions makes the calculation of the nucleon axial charge particularly easy since the Ward-Takahashi identity requires the vector and axial-vector currents to have the same renormalization, up to lattice spacing errors of order O(a^2). The DBW2 gauge action provides enhancement of the good chiral symmetry properties of domain wall fermions at larger lattice spacing than the conventional Wilson gauge action. Taking advantage of these methods and performing a high statistics simulation, we find a significant finite volume effect between the nucleon axial charges calculated on lattices with (1.2 fm)^3 and (2.4 fm)^3 volumes (with lattice spacing, a, of about 0.15 fm). On the large volume we find gA = 1.212 +/- 0.027(statistical error) +/- 0.024(normalization error). The quoted systematic error is the dominant (known) one, corresponding to current renormalization. We discuss other possible remaining sources of error. This theoretical first principles calculation, which does not yet include isospin breaking effects, yields a value of gA only a little bit below the experimental one, 1.2670 +/- 0.0030.

  1. HIGH-SPEED AXIAL-FLUX PERMANENT MAGNET MICROMOTORS WITH ELECTROPLATED WINDINGS

    E-Print Network [OSTI]

    the other. The folded-coil stator fabrication process is detailed, followed by the motor driver topology- plated multi-phase stator windings and their use in a high-speed permanent magnet micromotor. As the stator windings of an axial- flux micromotor, both single-plated folded coils, and two-layer double

  2. Proterozoic low orbital obliquity and axial-dipolar geomagnetic field from

    E-Print Network [OSTI]

    record. Magnetic inclinations are consistent with low orbital obliquity and a geocentric-axial-dipole magnetic field for most of the past two billion years, and the snowball Earth hypothesis accordingly tropical oceans6,7 . An alternative to global refrigeration invokes a high Precambrian planetary obliquity

  3. Reducing axial offset and improving stability in PWRs by using uraniumethorium fuel

    E-Print Network [OSTI]

    Demazière, Christophe

    Reducing axial offset and improving stability in PWRs by using uraniumethorium fuel Cheuk Wah Lau a that a new type uraniumethorium (UeTh) based fuel assembly could be used to achieve a more homogenous radial that a core containing UeTh fuel assemblies also reduces the AO and improves the core stability

  4. Hydrogen bonding preference of equatorial versus axial hydroxyl groups in pyran and cyclohexane rings in organic crystals

    E-Print Network [OSTI]

    de Gispert, Adrià

    Paper Hydrogen bonding preference of equatorial versus axial hydroxyl groups in pyran of the hydrogen bonding counts in crystalline pyranose monosaccharides, we noticed that equatorial hydroxyls formed more hydrogen bonds, on average, than axial groups. A survey of the Cambridge Structural Database

  5. Convective Heat Transfer and Reference Free-stream Temperature Determination near the Casing of an Axial Flow

    E-Print Network [OSTI]

    Camci, Cengiz

    of an Axial Flow Turbine B. Gumusel 2 and C. Camci 1 Turbomachinery Aero-Heat Transfer Laboratory Department on the casing of an axial flow turbine. The goal is to develop an accurate steady-state heat transfer method for the comparison of various casing surface and tip designs used for turbine performance improvements. The free

  6. 516 OPTICS LETTERS / Vol. 28, No. 7 / April 1, 2003 Optical bistability in axially modulated OmniGuide fibers

    E-Print Network [OSTI]

    demonstrate the feasibility of optical bistability in an axially modulated nonlinear OmniGuide fiber through516 OPTICS LETTERS / Vol. 28, No. 7 / April 1, 2003 Optical bistability in axially modulated OmniGuide fibers Marin Soljacic´, Mihai Ibanescu, Steven G. Johnson, and J. D. Joannopoulos Department of Physics

  7. Volume 152, number 4,s CHEMICAL PHYSICS LETTERS 18 November 1988 NON-INTRUSIVE MEASUREMENT OF AXIAL ELECTRIC FIELDS

    E-Print Network [OSTI]

    Cohen, Ronald C.

    Volume 152, number 4,s CHEMICAL PHYSICS LETTERS 18 November 1988 NON-INTRUSIVE MEASUREMENT OF AXIAL pertur- bations by sheath accumulation. Non-intrusive mea- surements of the electric fields through for the non- perturbative measurement of the axial electric fields in glow discharges. The A `n, + X I&+ (4

  8. Study of surface kinetics in PECVD chamber cleaning using remote plasma source

    E-Print Network [OSTI]

    An, Ju Jin

    2008-01-01T23:59:59.000Z

    The scope of this research work is to characterize the Transformer Coupled Toroidal Plasma (TCTP); to understand gas phase reactions and surface reactions of neutrals in the cleaning chamber by analyzing the concentration ...

  9. in the APS Storage Ring Vacuum Chamber Y. Chung Abstract LS-148

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Compensation for the Eddy Current Effect in the APS Storage Ring Vacuum Chamber Y. Chung Abstract LS-148 Y. Chung 053090 The amplitude attenuation and the phase shift of the...

  10. Potential applications of the natural design of internal explosion chambers in the bombardier beetle (Carabidae, Brachinus)

    E-Print Network [OSTI]

    Lai, Changquan

    2010-01-01T23:59:59.000Z

    The Bombardier Beetle (Carabidae, Brachinus) has a unique form of defense mechanism which involves the explosive mixing of hydroquinones and hydrogen peroxide in its internal explosion chambers and using the resultant high ...

  11. Monte Carlo calculations of electron beam quality conversion factors for several ion chamber types

    SciTech Connect (OSTI)

    Muir, B. R., E-mail: Bryan.Muir@nrc-cnrc.gc.ca [Measurement Science and Standards, National Research Council Canada, 1200 Montreal Road, Ottawa, Ontario K1A 0R6 (Canada); Rogers, D. W. O., E-mail: drogers@physics.carleton.ca [Carleton Laboratory for Radiotherapy Physics, Physics Department, Carleton University, 1125 ColonelBy Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2014-11-01T23:59:59.000Z

    Purpose: To provide a comprehensive investigation of electron beam reference dosimetry using Monte Carlo simulations of the response of 10 plane-parallel and 18 cylindrical ion chamber types. Specific emphasis is placed on the determination of the optimal shift of the chambers’ effective point of measurement (EPOM) and beam quality conversion factors. Methods: The EGSnrc system is used for calculations of the absorbed dose to gas in ion chamber models and the absorbed dose to water as a function of depth in a water phantom on which cobalt-60 and several electron beam source models are incident. The optimal EPOM shifts of the ion chambers are determined by comparing calculations of R{sub 50} converted from I{sub 50} (calculated using ion chamber simulations in phantom) to R{sub 50} calculated using simulations of the absorbed dose to water vs depth in water. Beam quality conversion factors are determined as the calculated ratio of the absorbed dose to water to the absorbed dose to air in the ion chamber at the reference depth in a cobalt-60 beam to that in electron beams. Results: For most plane-parallel chambers, the optimal EPOM shift is inside of the active cavity but different from the shift determined with water-equivalent scaling of the front window of the chamber. These optimal shifts for plane-parallel chambers also reduce the scatter of beam quality conversion factors, k{sub Q}, as a function of R{sub 50}. The optimal shift of cylindrical chambers is found to be less than the 0.5 r{sub cav} recommended by current dosimetry protocols. In most cases, the values of the optimal shift are close to 0.3 r{sub cav}. Values of k{sub ecal} are calculated and compared to those from the TG-51 protocol and differences are explained using accurate individual correction factors for a subset of ion chambers investigated. High-precision fits to beam quality conversion factors normalized to unity in a beam with R{sub 50} = 7.5 cm (k{sub Q}{sup ?}) are provided. These factors avoid the use of gradient correction factors as used in the TG-51 protocol although a chamber dependent optimal shift in the EPOM is required when using plane-parallel chambers while no shift is needed with cylindrical chambers. The sensitivity of these results to parameters used to model the ion chambers is discussed and the uncertainty related to the practical use of these results is evaluated. Conclusions: These results will prove useful as electron beam reference dosimetry protocols are being updated. The analysis of this work indicates that cylindrical ion chambers may be appropriate for use in low-energy electron beams but measurements are required to characterize their use in these beams.

  12. Towards energy resolution at the statistical limit from a negative ion time projection chamber

    E-Print Network [OSTI]

    Peter Sorensen; Mike Heffner; Adam Bernstein; Josh Renner; Melinda Sweany

    2012-05-29T23:59:59.000Z

    We make a proof-of-principle demonstration that improved energy resolution can be obtained in a negative-ion time projection chamber, by individually counting each electron produced by ionizing radiation.

  13. Blood meal host preferences of Culex salinarius Coquillett (Diptera : culicidae) in Chambers County, Texas

    E-Print Network [OSTI]

    Grieco, John Paul

    1994-01-01T23:59:59.000Z

    on a monthly basis from three field sites in Chambers County, TX. The source of blood contained in each specimen was determined using a modified precipitin test. The results were used to calculate seasonal foraging ratios for mosquito populations...

  14. A sun-tracking environmental chamber for the outdoor quantification of CPV modules

    SciTech Connect (OSTI)

    Faiman, David, E-mail: faiman@bgu.ac.il; Melnichak, Vladimir, E-mail: faiman@bgu.ac.il; Bokobza, Dov, E-mail: faiman@bgu.ac.il; Kabalo, Shlomo, E-mail: faiman@bgu.ac.il [Department of Solar Energy and Environmental Physics, Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 8499000 (Israel)

    2014-09-26T23:59:59.000Z

    The paper describes a sun-tracking environmental chamber and its associated fast electronics, devised for the accurate outdoor characterization of CPV cells, receivers, mono-modules, and modules. Some typical measurement results are presented.

  15. Impact of beam transport method on chamber and driver design for heavy ion inertial fusion energy

    E-Print Network [OSTI]

    Rose, D.V.; Welch, D.R.; Olson, C.L.; Yu, S.S.; Neff, S.; Sharp, W.M.

    2002-01-01T23:59:59.000Z

    A. Moses, “Inertial fusion energy target output and chamberA. J. Schmitt, et al. , “Fusion energy research with lasers,o?s for inertial fusion energy power plants,” presented at

  16. Resistive Wall Heating Due to Image Current on the Beam Chamber

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    32012 Resistive Wall Heating Due to Image Current on the Beam Chamber For a Superconducting Undulator S.H. Kim, ASD MD Group 1. Introduction The image-current heating on the...

  17. COUPP - a search for dark matter with a continuously sensitive bubble chamber

    SciTech Connect (OSTI)

    Collar, Juan,; Crum, Keith; Mishra, Smriti; Nakazawa, Dante; Odom, Brian; Rasmussen, Julia; Riley, Nathan; Szydagis, Matthew; /Chicago U.; Behnke, Ed; Levine, Ilan; Vander Werf, Nate; /Indiana U., South Bend; Cooper, Peter; Crisler, Mike; Hu, Martin; Ramberg, Erik; Sonnenschein, Andrew; Tschirhart, Robert; /Fermilab

    2007-01-01T23:59:59.000Z

    We propose to construct and operate a 60-kg room temperature CF{sub 3}I bubble chamber as a prototype dark matter (WIMP) detector. Operating in weakly-superheated mode, the chamber will be sensitive to WIMP induced nuclear recoils above 10 keV, while rejecting background electron recoils at a level approaching 10{sup 10}. We would first commission and operate this chamber in the MINOS near detector hall with the goal to demonstrate stable operation and measure internal contamination and any other backgrounds. This chamber, or an improved version, would then be relocated to an appropriate deep underground site such as the Soudan Mine. This detector will have unique sensitivity to spin-dependent WIMP-nucleon couplings, and even in this early stage of development will attain competitive sensitivity to spin-independent couplings.

  18. Pressemeddelelse: JCI (Junior Chamber International) Danmark uddelte 3 TOYP-priser

    E-Print Network [OSTI]

    Andersen, Anja C.

    Pressemeddelelse: JCI (Junior Chamber International) Danmark uddelte 3 TOYP-priser lørdag den 7 forståelse og integration mellem forskellige kulturer og folkeslag i Danmark. Outlandish er ydermere gode

  19. Method of correcting eddy current magnetic fields in particle accelerator vacuum chambers

    DOE Patents [OSTI]

    Danby, Gordon T. (Wading River, NY); Jackson, John W. (Shoreham, NY)

    1991-01-01T23:59:59.000Z

    A method for correcting magnetic field aberrations produced by eddy currents induced in a particle accelerator vacuum chamber housing is provided wherein correction windings are attached to selected positions on the housing and the windings are energized by transformer action from secondary coils, which coils are inductively coupled to the poles of electro-magnets that are powered to confine the charged particle beam within a desired orbit as the charged particles are accelerated through the vacuum chamber by a particle-driving rf field. The power inductively coupled to the secondary coils varies as a function of variations in the power supplied by the particle-accelerating rf field to a beam of particles accelerated through the vacuum chamber, so the current in the energized correction coils is effective to cancel eddy current flux fields that would otherwise be induced in the vacuum chamber by power variations in the particle beam.

  20. Method of correcting eddy current magnetic fields in particle accelerator vacuum chambers

    DOE Patents [OSTI]

    Danby, G.T.; Jackson, J.W.

    1990-03-19T23:59:59.000Z

    A method for correcting magnetic field aberrations produced by eddy currents induced in a particle accelerator vacuum chamber housing is provided wherein correction windings are attached to selected positions on the housing and the windings are energized by transformer action from secondary coils, which coils are inductively coupled to the poles of electro-magnets that are powered to confine the charged particle beam within a desired orbit as the charged particles are accelerated through the vacuum chamber by a particle-driving rf field. The power inductively coupled to the secondary coils varies as a function of variations in the power supplied by the particle-accelerating rf field to a beam of particles accelerated through the vacuum chamber, so the current in the energized correction coils is effective to cancel eddy current flux fields that would otherwise be induced in the vacuum chamber by power variations (dB/dt) in the particle beam.

  1. The design, fabrication, and implications of a solvothermal vapor annealing chamber

    E-Print Network [OSTI]

    Porter, Nathaniel R., Jr

    2013-01-01T23:59:59.000Z

    This thesis documents the design, fabrication, use, and benefits of a prototype aluminum solvothermal vapor annealing chamber which facilitates the self-assembly of block copolymers (BCPs) on silicon wafers which are then ...

  2. Conceptual Study of Integrated Chamber Core for Laser Fusion with Magnetic Intervention

    E-Print Network [OSTI]

    Raffray, A. René

    pumping, tritium extraction, and chamber coolant coupling to a heat exchanger (to drive the final product plasma cloud. The j x B force on the electrons is thus transferred to the ions which appear to push

  3. Performance of the beam chamber vacuum system of K = 500 cyclotron at Variable Energy Cyclotron Centre Kolkata

    SciTech Connect (OSTI)

    Pal, Gautam, E-mail: gautam.pal@vecc.gov.in; DuttaGupta, Anjan; Chakrabarti, Alok [Variable Energy Cyclotron Centre, I/AF Bidhannagar, Kolkata 700064 (India)

    2014-07-15T23:59:59.000Z

    The beam chamber of Variable Energy Cyclotron Centre, Kolkata's K = 500 superconducting cyclotron is pumped by liquid helium cooled cryopanel with liquid nitrogen cooled radiation shield. Performance of the vacuum system was evaluated by cooling the cryopanel assembly with liquid nitrogen and liquid helium. Direct measurement of beam chamber pressure is quite difficult because of space restrictions and the presence of high magnetic field. Pressure gauges were placed away from the beam chamber. The beam chamber pressure was evaluated using a Monte Carlo simulation software for vacuum system and compared with measurements. The details of the vacuum system, measurements, and estimation of pressure of the beam chamber are described in this paper.

  4. The Effect of Heat Treatments and Coatings on the Outgassing Rate of Stainless Steel Chambers

    SciTech Connect (OSTI)

    Mamum, Md Abdullah A. [Old Dominion Univ., Norfolk, VA (United States); Elmustafa, Abdelmageed A, [Old Dominion Univ., Norfolk, VA (United States); Stutzman, Marcy L. [JLAB, Newport News, VA (United States); Adderley, Philip A. [JLAB, Newport News, VA (United States); Poelker, Matthew [JLAB, Newport News, VA (United States)

    2014-03-01T23:59:59.000Z

    The outgassing rates of four nominally identical 304L stainless steel vacuum chambers were measured to determine the effect of chamber coatings and heat treatments. One chamber was coated with titanium nitride (TiN) and one with amorphous silicon (a-Si) immediately following fabrication. One chamber remained uncoated throughout, and the last chamber was first tested without any coating, and then coated with a-Si following a series of heat treatments. The outgassing rate of each chamber was measured at room temperatures between 15 and 30 deg C following bakes at temperatures between 90 and 400 deg C. Measurements for bare steel showed a significant reduction in the outgassing rate by more than a factor of 20 after a 400 deg C heat treatment (3.5 x 10{sup 12} TorrL s{sup -1}cm{sup -2} prior to heat treatment, reduced to 1.7 x 10{ sup -13} TorrL s{sup -1}cm{sup -2} following heat treatment). The chambers that were coated with a-Si showed minimal change in outgassing rates with heat treatment, though an outgassing rate reduced by heat treatments prior to a-Si coating was successfully preserved throughout a series of bakes. The TiN coated chamber exhibited remarkably low outgassing rates, up to four orders of magnitude lower than the uncoated stainless steel. An evaluation of coating composition suggests the presence of elemental titanium which could provide pumping and lead to an artificially low outgassing rate. The outgassing results are discussed in terms of diffusion-limited versus recombination-limited processes.

  5. Invention and History of the Bubble Chamber (LBNL Summer Lecture Series)

    ScienceCinema (OSTI)

    Glaser, Don

    2011-04-28T23:59:59.000Z

    Summer Lecture Series 2006: Don Glaser won the 1960 Nobel Prize for Physics for his 1952 invention of the bubble chamber at Berkeley Lab, a type of particle detector that became the mainstay of high-energy physics research throughout the 1960s and 1970s. He discusses how, inspired by bubbles in a glass of beer, he invented the bubble chamber and detected cosmic-ray muons.

  6. NOVEL CHAMBER DESIGN FOR AN IN-VACUUM CRYO-COOLED MINI-GAP UNDULATOR.

    SciTech Connect (OSTI)

    HU, J.-P.; FOERSTER, C.L.; SKARITKA, J.R.; WATERMAN, D.

    2006-05-24T23:59:59.000Z

    A stainless steel, Ultra-High Vacuum (UHV) chamber, featuring a large vertical rectangular port (53''W by 16''H), has been fabricated to house the one-meter magnet assembly of a newly installed undulator insertion device for beamline X-25 at the National Synchrotron Light Source. To achieve UHV, the new chamber is equipped with a differential ion pump, NEG pump, nude ion gauge, residual gas analyzer, and an all metal roughing valve. Temperature of the magnet assembly is maintained below 90 C during vacuum bake. The large rectangular port cover is sealed to the main flange of the chamber using a one-piece flat aluminum gasket and special sealing surfaces developed exclusively by Nor-Cal Products, Inc. The large flange provides easy access to the gap of the installed magnet girders for in situ magnetic measurements and shimming. Special window ports were designed into the cover and chamber for manipulation of optical micrometers external to the chamber to provide precise measurements of the in-vacuum magnet gap. The vacuum chamber assembly features independently vacuum-isolated feedthroughs that can be used for either water-or-cryogenic refrigeration-cooling of the monolithic magnet girders. This would allow for cryogenic-cooled permanent magnet operation and has been successfully tested within temperature range of +100 C to -150 C. Details of the undulator assembly for beamline X-25 is described in the paper.

  7. Radiofrequency hydrogen ion source with permanent magnets providing axial magnetic field

    SciTech Connect (OSTI)

    Oikawa, Kohei, E-mail: oikawa@ecei.tohoku.ac.jp; Saito, Yuta; Komizunai, Shota; Takahashi, Kazunori; Ando, Akira [Department of Electrical Engineering, Tohoku University, Sendai 980-8579 (Japan)] [Department of Electrical Engineering, Tohoku University, Sendai 980-8579 (Japan)

    2014-02-15T23:59:59.000Z

    Uniform axial magnetic field of about 70 G is applied to a radiofrequency (rf) hydrogen ion source by arrays of permanent magnets. The plasma density and electron temperature downstream of the source and near the magnetic filter are compared with those in the previously described ion source, where the axial field has been applied by two solenoids. The source is operated at ?350 kHz and above 10 kW rf power with a field-effect-transistor-based invertor power supply in 1.5 Pa hydrogen. The results show that the plasma density of ?10{sup 19} m{sup ?3} near the source exit and ?10{sup 18} m{sup ?3} near the magnetic filter can be obtained, which are higher than those with the solenoids.

  8. Theoretical and experimental investigation of axial power extraction from a magnetically insulated transmission line oscillator

    SciTech Connect (OSTI)

    Lemke, R.W.; DeMuth, G.E.; Biggs, A.W. (Sandia National Labs., Albuquerque, NM (USA); Air Force Weapons Lab., Kirtland AFB, NM (USA); Alabama Univ., Huntsville, AL (USA). Dept. of Electrical and Computer Engineering)

    1989-01-01T23:59:59.000Z

    The utility of the magnetically insulated transmission line oscillator (MILO) as a high power microwave source depends on how efficiently power can be extracted from it. We have designed a slow-wave stepped transformer for the purpose of axially extracting microwave power from a 3.6 GHz coaxial MILO. The slow-wave transformer design was optimized using particle-in-cell simulation, and tested in experiments performed on the HPM Simulation Division's GEMINI and GYPSY water Blumlein pulse power sources. In this paper we summarize the slow-wave stepped transformer design, and describe MILO axial power extraction experiments which yielded up to 300 MW of radiated power. 10 refs., 4 figs., 2 tabs.

  9. Axial anomaly of QED in a strong magnetic field and noncommutative anomaly

    SciTech Connect (OSTI)

    Sadooghi, N. [Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran (Iran, Islamic Republic of); Institute for Studies in Theoretical Physics and Mathematics (IPM), School of Physics, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); Jafari Salim, A. [Department of Physics, Sharif University of Technology, P.O. Box 11365-9161, Tehran (Iran, Islamic Republic of)

    2006-10-15T23:59:59.000Z

    The Adler-Bell-Jackiw (ABJ) anomaly of a 3+1 dimensional QED is calculated in the presence of a strong magnetic field. It is shown that in the regime with the lowest Landau level (LLL) dominance a dimensional reduction from D=4 to D=2 dimensions occurs in the longitudinal sector of the low energy effective field theory. In the chiral limit, the resulting anomaly is therefore comparable with the axial anomaly of a two-dimensional massless Schwinger model. It is further shown that the U{sub A}(1) anomaly of QED in a strong magnetic field is closely related to the nonplanar axial anomaly of a conventional noncommutative U(1) gauge theory.

  10. Neutrino- and antineutrino-deuteron elastic scattering and the axial isoscalar nucleon current

    SciTech Connect (OSTI)

    Frederico, T.; Henley, E.M.; Pollock, S.J.; Ying, S. (Department of Physics, FM-15 and Institute for Nuclear Theory, HN-12, University of Washington, Seattle, Washington 98195 (United States))

    1992-07-01T23:59:59.000Z

    We calculate the neutrino and antineutrino elastic scattering cross section on unpolarized deuterons at energies from a few MeV to several GeV and squared momentum transfers up to 5 GeV{sup 2}. These cross sections can be used to deduce the unknown weak SU(2) isoscalar and SU(3) flavor-scalar axial-vector coupling to nucleons. This observable can be related to the strangeness axial-vector matrix element in the absence of QCD radiative or isospin-violating corrections. We show that the unknown weak magnetic vector coupling may also be gleaned from these measurements. We use different techniques at different energies, including light-cone impulse approximation at the highest energies, and show that they connect smoothly to each other.

  11. Comments on the U(1) axial symmetry and the chiral transition in QCD

    E-Print Network [OSTI]

    Enrico Meggiolaro

    2014-10-14T23:59:59.000Z

    We analyze (using a chiral effective Lagrangian model) the scalar and pseudoscalar meson mass spectrum of QCD at finite temperature, above the chiral transition at $T_c$, looking, in particular, for signatures of a possible breaking of the $U(1)$ axial symmetry above $T_c$. A detailed comparison between the case with a number of light quark flavors $N_f\\geq 3$ and the (remarkably different) case $N_f=2$ is performed.

  12. Scattering of particles by neutron stars: Time-evolutions for axial perturbations

    E-Print Network [OSTI]

    V. Ferrari; K. D. Kokkotas

    2000-08-23T23:59:59.000Z

    The excitation of the axial quasi-normal modes of a relativistic star by scattered particles is studied by evolving the time dependent perturbation equations. This work is the first step towards the understanding of more complicated perturbative processes, like the capture or the scattering of particles by rotating stars. In addition, it may serve as a test for the results of the full nonlinear evolution of binary systems.

  13. The development of blade profiles for a supersonic axial flow compressor

    E-Print Network [OSTI]

    Bearden, John Lee

    1972-01-01T23:59:59.000Z

    . Therefore, the Mach number before the normal shock is reduced, thereby reducing the shock losses. The adiabatic efficiency obtained was fairly low (0. 67). The authors attributed this to the detached bow wave remaining at the rotor inlet... be used when ). (t/c) is small compared to unity (28) . The last condi- tion is satisfied as long as the bow or leading edge shock is attached. Applying linearized theory to the flow problem in axial com- pressor rotors and stators, equations can...

  14. Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar

    SciTech Connect (OSTI)

    Gandini, Paolo; /Milan U. /INFN, Milan

    2012-04-06T23:59:59.000Z

    We present experimental measurements of branching fraction and longitudinal polarization fraction in charmless hadronic B decays into vector, axial vector and tensor final states with the final dataset of BABAR. Measurements of such kind of decays are a powerful tool both to test the Standard Model and search possible sources of new physics. In this document we present a short review of the last experimental results at BABAR concerning charmless quasi two-body decays in final states containing particles with spin 1 or spin 2 and different parities. This kind of decays has received considerable theoretical interest in the last few years and this particular attention has led to interesting experimental results at the current b-factories. In fact, the study of longitudinal polarization fraction f{sub L} in charmless B decays to vector vector (VV), vector axial-vector (VA) and axial-vector axial-vector (AA) mesons provides information on the underlying helicity structure of the decay mechanism. Naive helicity conservation arguments predict a dominant longitudinal polarization fraction f{sub L} {approx} 1 for both tree and penguin dominated decays and this pattern seems to be confirmed by tree-dominated B {yields} {rho}{rho} and B{sup +} {yields} {Omega}{rho}{sup +} decays. Other penguin dominated decays, instead, show a different behavior: the measured value of f{sub L} {approx} 0.5 in B {yields} {phi}K* decays is in contrast with naive Standard Model (SM) calculations. Several solutions have been proposed such as the introduction of non-factorizable terms and penguin-annihilation amplitudes, while other explanations invoke new physics. New modes have been investigated to shed more light on the problem.

  15. Using electron scattering to constrain the axial-vector form factor

    E-Print Network [OSTI]

    R. González-Jiménez; J. A. Caballero; T. W. Donnelly

    2015-01-16T23:59:59.000Z

    We present an analysis of elastic and quasielastic parity-violating (PV) electron scattering processes. These reactions can help to constrain the weak neutral current form factors of the nucleon that play an essential role in the description of neutrino cross sections at intermediate energies. We show that combining information from the analysis of elastic and quasielastic reactions the current knowledge on the strange and axial-vector form factors can be significantly improved.

  16. Using electron scattering to constrain the axial-vector form factor

    E-Print Network [OSTI]

    González-Jiménez, R; Donnelly, T W

    2015-01-01T23:59:59.000Z

    We present an analysis of elastic and quasielastic parity-violating (PV) electron scattering processes. These reactions can help to constrain the weak neutral current form factors of the nucleon that play an essential role in the description of neutrino cross sections at intermediate energies. We show that combining information from the analysis of elastic and quasielastic reactions the current knowledge on the strange and axial-vector form factors can be significantly improved.

  17. Computation of the Field in an Axial Gap, Trapped-Flux Type Superconducting Electric Machine

    E-Print Network [OSTI]

    Shen, Zejun; Ainslie, Mark D.; Campbell, Archie M.; Cardwell, David A.

    2014-11-04T23:59:59.000Z

    Abstract—The Bulk Superconductivity Group at the University of Cambridge is currently investigating the use of high temper- ature superconductors in wire and bulk form to increase the electrical and magnetic loading of an axial gap, trapped flux... electric machines are an importantapplication of superconducting materials in both bulk and wire forms. Bulk high temperature superconductors, in partic- ular, are capable of trapping magnetic fields greater than 17 T below 30 K [1], [2], as well as up to 3...

  18. NATURE GEOSCIENCE | VOL 5 | APRIL 2012 | www.nature.com/naturegeoscience 235 news & views

    E-Print Network [OSTI]

    Toomey, Doug

    of the magma chamber is also rapid. In contrast, where plates spread apart more slowly, the heat supply is also

  19. Mimicking Mars: A vacuum simulation chamber for testing environmental instrumentation for Mars exploration

    SciTech Connect (OSTI)

    Sobrado, J. M., E-mail: sobradovj@inta.es; Martín-Soler, J. [Centro de Astrobiología (CAB), INTA-CSIC, Torrejón de Ardoz, 28850 Madrid (Spain)] [Centro de Astrobiología (CAB), INTA-CSIC, Torrejón de Ardoz, 28850 Madrid (Spain); Martín-Gago, J. A. [Centro de Astrobiología (CAB), INTA-CSIC, Torrejón de Ardoz, 28850 Madrid (Spain) [Centro de Astrobiología (CAB), INTA-CSIC, Torrejón de Ardoz, 28850 Madrid (Spain); Instituto de Ciencias de Materiales de Madrid (ICMM-CSIC), Cantoblanco, 28049 Madrid (Spain)

    2014-03-15T23:59:59.000Z

    We have built a Mars environmental simulation chamber, designed to test new electromechanical devices and instruments that could be used in space missions. We have developed this environmental system aiming at validating the meteorological station Rover Environment Monitoring Station of NASA's Mars Science Laboratory mission currently installed on Curiosity rover. The vacuum chamber has been built following a modular configuration and operates at pressures ranging from 1000 to 10{sup ?6} mbars, and it is possible to control the gas composition (the atmosphere) within this pressure range. The device (or sample) under study can be irradiated by an ultraviolet source and its temperature can be controlled in the range from 108 to 423 K. As an important improvement with respect to other simulation chambers, the atmospheric gas into the experimental chamber is cooled at the walls by the use of liquid-nitrogen heat exchangers. This chamber incorporates a dust generation mechanism designed to study Martian-dust deposition while modifying the conditions of temperature, and UV irradiated.

  20. Manipulating Magnetism: Ru-2(5+) Paddlewheels Devoid of Axial Interactions

    SciTech Connect (OSTI)

    Chiarella, Gina M [Texas A& M University; Cotton, F. A. [Texas A& M University; Murillo, Carlos A [Texas A& M University; Ventura, Karen [University of Texas at El Paso; Vilagran, Dino [University of Texas at El Paso; Wang, Xiaoping [ORNL

    2014-01-01T23:59:59.000Z

    Variable-temperature magnetic and structural data of two pairs of diruthenium isomers, one pair having an axial ligand and the formula Ru-2(DArF)(4)Cl (where DArF is the anion of a diarylformamidine isomer and Ar = p-anisyl or m-anisyl) and the other one being essentially identical but devoid of axial ligands and having the formula [Ru-2(DArF)(4)]BF4, show that the axial ligand has a significant effect on the electronic structure of the diruthenium unit. Variable temperature crystallographic and magnetic data as well as density functional theory calculations unequivocally demonstrate the occurrence of pi interactions between the p orbitals of the chlorine ligand and the pi* orbitals in the Ru-2(5+) units. The magnetic and structural data are consistent with the existence of combined ligand sigma/metal sigma and ligand p pi/metal-d pi interactions. Electron paramagnetic resonance data show unambiguously that the unpaired electrons are in metal-based molecular orbitals.

  1. Torsional Alfven Waves in Solar Magnetic Flux Tubes of Axial Symmetry

    E-Print Network [OSTI]

    Murawski, K; Musielak, Z E; Srivastava, A K; Kraskiewicz, J

    2015-01-01T23:59:59.000Z

    Aims: Propagation and energy transfer of torsional Alfv\\'en waves in solar magnetic flux tubes of axial symmetry is studied. Methods: An analytical model of a solar magnetic flux tube of axial symmetry is developed by specifying a magnetic flux and deriving general analytical formulae for the equilibrium mass density and a gas pressure. The main advantage of this model is that it can be easily adopted to any axisymmetric magnetic structure. The model is used to simulate numerically the propagation of nonlinear Alfv\\'en waves in such 2D flux tubes of axial symmetry embedded in the solar atmosphere. The waves are excited by a localized pulse in the azimuthal component of velocity and launched at the top of the solar photosphere, and they propagate through the solar chromosphere, transition region, and into the solar corona. Results: The results of our numerical simulations reveal a complex scenario of twisted magnetic field lines and flows associated with torsional Alfv\\'en waves as well as energy transfer to t...

  2. Design and market considerations for axial flux superconducting electric machine design

    E-Print Network [OSTI]

    Ainslie, Mark D; Shaw, Robert; Dawson, Lewis; Winfield, Andy; Steketee, Marina; Stockley, Simon

    2013-01-01T23:59:59.000Z

    In this paper, the authors investigate a number of design and market considerations for an axial flux superconducting electric machine design that uses high temperature superconductors. This work was carried out as part of the University of Cambridge's Centre for Entrepreneurial Learning ETECH Project programme, designed to accelerate entrepreneurship and diffusion of innovations based on early stage and potentially disruptive technologies from the University. The axial flux machine design is assumed to utilise high temperature superconductors in both wire (stator winding) and bulk (rotor field) forms, to operate over a temperature range of 65-77 K, and to have a power output in the range from 10s of kW up to 1 MW (typical for axial flux machines), with approximately 2-3 T as the peak trapped field in the bulk superconductors. The authors firstly investigate the applicability of this type of machine as a generator in small- and medium-sized wind turbines, including the current and forecasted market and pricin...

  3. A strontium and neodymium isotopic study of Apollo 17 high-Ti mare basalts: Resolution of ages, evolution of magmas, and origins of source heterogeneities

    SciTech Connect (OSTI)

    Paces, J.B.; Neal, C.R.; Taylor, L.A. (Univ. of Tennessee, Knoxville (United States)); Nakai, Shun'ichi; Halliday, A.N.; Lee, D.C. (Univ. of Michigan, Ann Arbor (United States))

    1991-07-01T23:59:59.000Z

    A combined Sr and Nd isotopic study of 15 Apollo 17 high-Ti mare basalts was undertaken to investigate geochronological and compositional differences between previously identified magma types (A, B1, B2, and C). Whole-rock and mineral separates for one of the least-evolved Type B1 basalts, 70139, yield Sm-Nd and Rb-Sr isochron ages of 3.71 {plus minus} 0.12 Ga and 3.65 {plus minus} 0.07 Ga and a Rb-Sr isochron age of 3.67 {plus minus} 0.10 Ga. Although these two ages are non-resolvable by themselves, compilation of all available geochronological data allows resolution of Type A and B1/B2 ages at high levels of confidence (> 99%). The most reliably dated samples, classified according to their geochemical type, yield weighted average ages of 3.75 {plus minus} 0.02 Ga for Type A (N = 4) and 3.69 {plus minus} 0.02 Ga for Type B1/B2 (N = 3) basalts. Insufficient geochronological data are available to place the rare, Type C basalts within this stratigraphy. The authors propose that age differences correlate with geochemical magma type, and that early magmatism was dominated by eruption of Type A basalts while later activity was dominated by effusion of Type B1 and B2 basalts.

  4. Effects of outgassing of loader chamber walls on hydriding of thin films for commercial applications

    SciTech Connect (OSTI)

    Provo, James L., E-mail: jlprovo@verizon.net [Consultant, J.L. Provo Consulting, Trinity, Florida 34655-7179 (United States)

    2014-07-01T23:59:59.000Z

    An important aspect of understanding industrial processing is to know the characteristics of the materials used in such processes. A study was performed to determine the effects of hydriding chamber material on the degree of hydriding for the commercial production of thin film hydride targets for various research universities, commercial companies, and government national laboratories. The goal was to increase the degree of hydriding of various thin film hydrides and to study the vacuum environment during air-exposure hydriding. For this purpose, dynamic residual gas analysis during deuterium gas hydride processing was utilized with erbium thin films, employing a special set-up for direct dynamic hydride gas sampling during processing at elevated temperature and full loading gas pressure. Complete process data for (1) a copper–(1.83?wt.?%)beryllium wet hydrogen fired passivated (600?°C–1?h) externally heated pipe hydriding chamber are reported. Dynamic residual gas analysis comparisons during hydriding are presented for hydriding chambers made from (2) alumina (99.8 wt.?%), (3) copper (with an interior aluminum coating ?10 k Å thick, and (4) for a stainless-steel air-fired passivated (900?°C–1?h) chamber. Dynamic data with deuterium gas in the chamber at the hydriding temperature (450?°C) showed the presence and growth of water vapor (D{sub 2}O) and related mixed ion species(H{sub 2}O{sup +}, HDO{sup +}, D{sub 2}O{sup +}, and OD{sup +}) from hydrogen isotope exchange reactions during the 1?h process time. Peaks at mass-to-charge ratios (i.e., m/e) of 12(C{sup +}), 16(CD{sub 2}{sup +}), 17(CHD{sub 2}{sup +}), and 18(CD{sub 3}{sup +}, OD{sup +}) increased for approximately the first half hour of a 1?h hydriding process and then approach steady state. Mass-to-charge peaks at 19(HDO{sup +}) and 20(D{sub 2}O{sup +}) continue to increase throughout the process cycle. Using the m/e?=?20 (D{sub 2}O{sup +}) peak intensity from chamber (1)–Cu(1.83 wt.?%)Be as a standard, the peak intensity from chamber (4)—stainless-steel (air-fired) was 7.1× higher, indicating that the surface of stainless-steel had a larger concentration of reactive oxygen and/or water than hydrogen. The (D{sub 2}O{sup +}) peak intensity from chamber (3)—Cu (interior Al coating) was 1.55× larger and chamber (2)—alumina(99.8%) was 1.33× higher than Cu(1.83 wt.?%)Be. Thus copper–(1.83 wt.?%)beryllium was the best hydriding chamber material studied followed closely by the alumina (99.8 wt.?%) chamber. Gas take-up by Er occluder targets processed in Cu(1.83?wt.?%)Be hydriding chambers (i.e., gas/metal atomic ratios) correlate with the dynamic RGA data.

  5. Front-end Electronics Test for the LHCb Muon Wire Chambers

    E-Print Network [OSTI]

    Nobrega, R; Carboni, G; Massafferri, A; Santovetti, E

    2007-01-01T23:59:59.000Z

    This document describes the apparatus and procedures implemented to test Multi Wire Proportional Chambers (MWPC) after front-end assembly for the LHCb Muon Detector. Results of measurements of key noise parameters are also described. Given a fully equipped chamber, this system is able to diagnose every channel performing an analysis of front-end output drivers’ response and noise rate versus threshold. Besides, it allows to assess if the noise rate at the experiment threshold region is within appropriate limits. Aiming at an automatic, fast and user-friendly system for mass production tests of MWPC, the project has foreseen as well electronic identification of every chamber and front-end board, and data archiving in such a way to make it available to the Experiment Control System (ECS) while in operation.

  6. Test Facility for Full-Equipped Chambers for the LHCb Muon Detector

    E-Print Network [OSTI]

    Nóbrega, Rafael

    2007-01-01T23:59:59.000Z

    The LHCb Muon System is made up by more than 1300 chambers of 20 different types, resulting in more than 120k readout channels. In order to guarantee high-quality performance during the experiment it is of crucial importance to get a complete knowledge of the fully equipped detector functionalities.A complete test system was built and a C++ ROOT software was developed to allow carring out a variety of studies on the many LHCb Muon chambers. Such system provides full control of the frontend, the high-voltage and the acquisition electronics and makes available a number of procedures to study the chambersâ?? performance. It was used for studies and a quality control on the chambers before and during the final positioning on the detector. In this note an overview of the hardware setup and of the software will be given. Results of measurements related to front-end channels characteristics will be presented.

  7. The High Momentum Spectrometer Drift Chambers in Hall C at CEBAF

    SciTech Connect (OSTI)

    Vulcan, William; Kross, Brian; Beaufait, Joseph; Baker, O.; Carlini, Roger; Majewski, Stanislaw; Johnson, A.; McCauley, A.; Niculescu, Gabriel; Niculescu, Maria-Ioana; Cha, Jinseok; Shin, Taeksu; Naing, Win; Danagoulian, Samuel

    1995-12-01T23:59:59.000Z

    The mutiwire drift chambers to be used in the High Momentum Spectrometer (HMS) at the Continuous Electron Beam Accelerator Facility (CEBAF) have been designed and constructed, and recently employed in initial data-taking runs.These chambers are used to reconstruct scattered charged particle momenta in the HMS using 12C and BeO2 targets for incident electron energies up to 2.2 GeV.Offline analysis of the data indicate that these drift chambers have spatial resolution (per plane) of about 115 mu-m (sigma) in rates approaching a KHz/wire/mm.It is expected that this performance will improve at higher momenta where multiple scattering contributions are smaller.

  8. UCRL-JC-138507 Overview of IFE Chamber and Target Technologies R&D in the U.S.

    E-Print Network [OSTI]

    Tillack, Mark

    ]) with heavy ion driven, indirect-drive targets, and the other is the gas-protected, dry-wall chamber (e with heavy-ion driven, indirect-drive targets are: a) Chamber Clearing: Can the liquid pocket and beam portUCRL-JC-138507 1 Overview of IFE Chamber and Target Technologies R&D in the U.S. W.R. Meier 1), M

  9. March 8, 2001 A. R. Raffray, et al., Assessment of Carbon and Tungsten Dry Chamber Walls under IFE Energy Depositions

    E-Print Network [OSTI]

    Raffray, A. René

    Chamber Walls under IFE Energy Depositions Ion Energy Deposition Calculations Electronic stopping power., Assessment of Carbon and Tungsten Dry Chamber Walls under IFE Energy Depositions Photon and Ion Attenuation for Ions Based on Given Spectrum and 6.5 m Chamber 0.0E+00 1.0E+13 2.0E+13 3.0E+13 4.0E+13 5.0E+13 6.0E+13

  10. Effect of Temporal Acquisition Parameters on the Image Quality of Ultrasound Axial Strain Time-constant Elastograms

    E-Print Network [OSTI]

    Varghese, Joshua

    2011-08-02T23:59:59.000Z

    constant (TC) have been developed. The axial strain TC is a parameter that is related to the viscoelastic and poroelastic behavior of tissues. Estimation of this parameter can be done using curve fitting methods. However, the effect of temporal...

  11. Construction and test of high precision drift-tube (sMDT) chambers for the ATLAS muon spectrometer

    E-Print Network [OSTI]

    Sebastian Nowak; Oliver Korner; Hubert Kroha; Philipp Schwegler; Federico Sforza

    2014-07-01T23:59:59.000Z

    For the upgrade of the ATLAS muon spectrometer in March 2014 new muon tracking chambers (sMDT) with drift-tubes of 15 mm diameter, half of the value of the standard ATLAS Monitored Drift-Tubes (MDT) chambers, and 10~$\\mu$m positioning accuracy of the sense wires have been constructed. The new chambers are designed to be fully compatible with the present ATLAS services but, with respect to the previously installed ATLAS MDT chambers, they are assembled in a more compact geometry and they deploy two additional tube layers that provide redundant rack information. The chambers are composed of 8 layers of in total 624 aluminium drift-tubes. The assembly of a chamber is completed within a week. A semi-automatized production line is used for the assembly of the drift-tubes prior to the chamber assembly. The production procedures and the quality control tests of the single components and of the complete chambers will be discussed. The wire position in the completed chambers have been measured by using a coordinate measuring machine.

  12. Multi-gap Resistive Plate Chambers as a Time-of-Flight System for the PHENIX Experiment

    SciTech Connect (OSTI)

    Velkovska, Julia [Vanderbilt University] [Vanderbilt University

    2013-12-08T23:59:59.000Z

    In this project a Time-of-Flight detector based on multi-gap resistive plate chambers was built and installed for the PHENIX experiment at RHIC.

  13. Selection of dimensions for the accelerating chamber of a betatron with extraction of an electron beam

    SciTech Connect (OSTI)

    Chakhlov, V.L.; Kashovskii, V.V.; Pushin, V.S.

    1985-09-01T23:59:59.000Z

    The authors discuss the results of refinement of the dynamics of particles of a beam extracted from a betatron, a refinement which has made it possible to select the main dimensions of the accelerating chamber. Expressions are obtained which make it possible to determine the chamber dimensions and the profile of the extraction window from the distribution of the magnetic field of the betatron. It is shown that proper selection of the dimensions will increase the dose rate at the exit from the magnetic core of the accelerator.

  14. Wafer chamber having a gas curtain for extreme-UV lithography

    DOE Patents [OSTI]

    Kanouff, Michael P. (Livermore, CA); Ray-Chaudhuri, Avijit K. (Livermore, CA)

    2001-01-01T23:59:59.000Z

    An EUVL device includes a wafer chamber that is separated from the upstream optics by a barrier having an aperture that is permeable to the inert gas. Maintaining an inert gas curtain in the proximity of a wafer positioned in a chamber of an extreme ultraviolet lithography device can effectively prevent contaminants from reaching the optics in an extreme ultraviolet photolithography device even though solid window filters are not employed between the source of reflected radiation, e.g., the camera, and the wafer. The inert gas removes the contaminants by entrainment.

  15. Calibration and performance of a secondary emission chamber as a beam intensity monitor

    SciTech Connect (OSTI)

    Sivertz, M.; Chiang, I-H,; Rusek, A.

    2011-03-28T23:59:59.000Z

    We report on a study of the behavior of a secondary emission chamber (SEC). We show the dependence of the SEC signal on the charge and velocity of the primary beam for beams of protons, and heavy ions including Helium, Neon, Chlorine and Iron. We fill the SEC with a selection of different gases including Hydrogen, Helium, Nitrogen, Argon, and air, studying the SEC response when it is acting as an ion chamber. We also investigate the behavior of the SEC at intermediate pressures between 10{sup -8} torr and atmospheric pressure. The SEC uses thin conducting foils as the source and collector of electrons in a vacuum chamber. When charged particles traverse the vacuum chamber, they pass through a series of thin conducting foils, alternating anode and cathode. Ionization produced in the cathode foils travels across the intervening gap due to an applied high voltage and is collected on the anode foils. Electron production is very inefficient because most of the ionization in the foils remains trapped within the foil due to the short range of most delta-rays and the work function of the foil. It is this inefficiency that allows the SEC to operate at high dose rates and short pulse duration where the standard ion chambers cannot function reliably. The SEC was placed in the NSRL ion beam to receive a variety of heavy ion beams under different beam conditions. We used these ion beams to study the response of the SEC to different species of heavy ion, comparing with proton beams. We studied the response to beam of different energies, and as a function of different counting rate. We compared the behaviour of the SEC when operating under positive and negative high voltage. The SEC can operate as an ion chamber if it is filled with gas. We measured the response of the SEC when filled with a variety of gases, from Hydrogen to Helium, Nitrogen, Argon and air. The performance of the SEC as an ion chamber is compared with the standard NSRL ion chamber, QC3. By evacuating the SEC and filling it with Nitrogen through an adjustable leak valve, we were able to measure the response of the SEC to beam as a function of gas pressure. Many interesting features of the SEC were revealed in these tests.

  16. A study of the response of a gas ionization chamber to different sources of ionizing radiation

    E-Print Network [OSTI]

    Zamble?-Die?guez, Filiberto Edmundo

    1988-01-01T23:59:59.000Z

    ; is the effective average energy to produce one pair (for values, see Table I). Charged particles produced by ionization lose their energy rather quickly in multiple collisions with the gas molecules and assume the thermal energy distribution of the gas. When... of aluminum extrusion ionization chambers to this kind of radiation was investigated. Also, since the TAMU counter is a prototype (1 in x 7in x 7in) of the chambers installed at CDF (1 in x 84in x 84in), the pad-to-wire signal ratio had to be measured...

  17. Design and performance testing of the read-out boards for the CMS-DT chambers

    E-Print Network [OSTI]

    Fernández, C; Marin, J; Oller, J C; Willmott, C

    2002-01-01T23:59:59.000Z

    Read-out boards (ROB) are one of the key elements of readout system for CMS barrel muon drift chambers. To insure proper and reliable operation under all detector environmental conditions an exhaustive set of tests have been developed and performed on the 30 pre-series ROB's before production starts. These tests include operation under CMS radiation conditions to detect and estimate SEU rates, validation with real chamber signals and trigger rates, studies of time resolution and linearity, crosstalk analysis, track pattern generation for calibration and on-line tests, and temperature cycling to uncover marginal conditions. We present the status of the ROB and tests results. (5 refs).

  18. IFE thick liquid wall chamber dynamics: Governing mechanisms andmodeling and experimental capabilities

    SciTech Connect (OSTI)

    Raffray, A.R.; Meier, W.; Abdel-Khalik, S.; Bonazza, R.; Calderoni, P.; Debonnel, C.S.; Dragojlovic, Z.; El-Guebaly, L.; Haynes,D.; Latkowski, J.; Olson, C.; Peterson, P.F.; Reyes, S.; Sharpe, P.; Tillack, M.S.; Zaghloul, M.

    2005-01-24T23:59:59.000Z

    For thick liquid wall concepts, it is important to understand the different mechanisms affecting the chamber dynamics and the state of the chamber prior to each shot a compared with requirements from the driver and target. These include ablation mechanisms, vapor transport and control, possible aerosol formation, as well as protective jet behavior. This paper was motivated by a town meeting on this subject which helped identify the major issues, assess the latest results, review the capabilities of existing modeling and experimental facilities with respect to addressing remaining issues, and helping guide future analysis and R&D efforts; the paper covers these exact points.

  19. Method for operating a nuclear reactor to accommodate load follow while maintaining a substantially constant axial power distribution

    SciTech Connect (OSTI)

    Mueller, N.P.; Rossi, C.E.; Scherpereel, L.R.

    1980-09-16T23:59:59.000Z

    This invention provides a method of operating a nuclear reactor having a negative reactivity moderator temperature coefficient with the object of maintaining a uniform and symmetric xenon distribution above and below substantially the center of the core over a substantial axial length of the core during normal reactor operation including load follow. In one embodiment variations in the xenon distribution are controlled by maintaining a substantially symmetric axial power distribution. The axial offset, which is employed as an indication of the axial power distribution, is maintained substantially equal to a target value , which is modified periodically to account for core burnup. A neutron absorbing element within the core coolant, or moderator, is employed to assist control of reactivity changes associated with changes in power, with the full-length control rods mainly employed to adjust variations in the axial power distribution while the part-length rodsremain completely withdrawn from the fuel region of the core. Rapid changes in reactivity are implemented, to accommodate corresponding changes in load, by a controlled reduction of the core coolant temperature. Thus, active core coolant temperature control is employed to control the reactivity of the core during load follow operation and effectively increase the spinning reserve capability of a power plant without altering the axial power distribution.

  20. Simulation of in-core neutron noise measurements for axial void profile reconstruction in boiling water reactors

    SciTech Connect (OSTI)

    Dykin, V.; Pazsit, I. [Chalmers Univ. of Technology, Div. of Nuclear Engineering, Dept. of Applied Physics, SE-412 96 Gothenburg (Sweden)

    2012-07-01T23:59:59.000Z

    A possibility to reconstruct the axial void profile from the simulated in-core neutron noise which is caused by density fluctuations in a Boiling Water Reactor (BWR) heated channel is considered. For this purpose, a self-contained model of the two-phase flow regime is constructed which has quantitatively and qualitatively similar properties to those observed in real BWRs. The model is subsequently used to simulate the signals of neutron detectors induced by the corresponding perturbations in the flow density. The bubbles are generated randomly in both space and time using Monte-Carlo techniques. The axial distribution of the bubble production is chosen such that the mean axial void fraction and void velocity follow the actual values of BWRs. The induced neutron noise signals are calculated and then processed by the standard signal analysis methods such as Auto-Power Spectral Density (APSD) and Cross-Power Spectral Density (CPSD). Two methods for axial void and velocity profiles reconstruction are discussed: the first one is based on the change of the break frequency of the neutron auto-power spectrum with axial core elevation, while the second refers to the estimation of transit times of propagating steam fluctuations between different axial detector positions. This paper summarizes the principles of the model and presents a numerical testing of the qualitative applicability to estimate the required parameters for the reconstruction of the void fraction profile from the neutron noise measurements. (authors)

  1. Journal of the Geological Society, London, Vol. 154, 1997, pp. 935946, 8 figs, 3 tables. Printed in Great Britain Geochemical and isotopic constraints on subduction polarity, magma sources, and

    E-Print Network [OSTI]

    Stern, Robert J.

    in Great Britain Geochemical and isotopic constraints on subduction polarity, magma sources, and palaeogeography of the Kohistan intra-oceanic arc, northern Pakistan Himalaya M. ASIF KHAN1 , ROBERT J. STERN2, Pakistan 2 Center for Lithospheric Studies, University of Texas at Dallas, Box 830688, Richardson, TX 75083

  2. MicroBooNE, A Liquid Argon Time Projection Chamber (LArTPC) Neutrino Experiment

    SciTech Connect (OSTI)

    Katori, Teppei

    2011-07-01T23:59:59.000Z

    Liquid Argon time projection chamber (LArTPC) is a promising detector technology for future neutrino experiments. MicroBooNE is a upcoming LArTPC neutrino experiment which will be located on-axis of Booster Neutrino Beam (BNB) at Fermilab, USA. The R&D efforts on this detection method and related neutrino interaction measurements are discussed.

  3. OPERATIONAL WINDOWS FOR DRY-WALL AND WETTED-WALL IFE CHAMBERS

    E-Print Network [OSTI]

    Raffray, A. René

    subsystems was performed parametrically to uncover key physics/technology uncertainties and to iden- tify be necessary that may preclude propagation of the laser driver and require assisted pinch transport issue for wetted-wall concepts. KEYWORDS: inertial fusion, fusion technology, IFE chambers *E

  4. Effect of nitrate on the performance of single chamber air cathode microbial fuel cells

    E-Print Network [OSTI]

    Tullos, Desiree

    Effect of nitrate on the performance of single chamber air cathode microbial fuel cells Chontisa Accepted 26 August 2008 Published online 11 September 2008 Keywords: Microbial fuel cell Denitrification microbial fuel cells (MFCs) has drawn much attention recently as a new approach of waste- water treatment

  5. Tungsten as first wall material in the main chamber of ASDEX Upgrade

    E-Print Network [OSTI]

    Tungsten as first wall material in the main chamber of ASDEX Upgrade V. Rohde, R. Neu, A. Geier, R material is tungsten, which has a high melting point, low erosion rate in cold scrape off layer plasma, where the present ITER-FEAT design uses tungsten. No negative influence on the plasma performance, even

  6. A UNIFIED MODEL FOR ION DEPOSITION AND THERMOMECHANICAL RESPONSE IN DRY WALL LASER IFE CHAMBERS

    E-Print Network [OSTI]

    Ghoniem, Nasr M.

    . INTRODUCTION In order to permit the design of an economically viable IFE power plant, we require a chamber wall reach the wall. These threats, consisting of x- rays, ions, and neutrons, can lead to wall failure associated with the IFE threats. In some cases, these inertial effects lead to stress waves that can lead

  7. Hydrogen production using single-chamber membrane-free microbial electrolysis cells

    E-Print Network [OSTI]

    Tullos, Desiree

    Hydrogen production using single-chamber membrane-free microbial electrolysis cells Hongqiang Hu Received in revised form 13 June 2008 Accepted 17 June 2008 Published online - Keywords: Hydrogen Microbial electrohydrogenesis provides a new approach for hydrogen generation from renewable biomass. Membranes were used in all

  8. Hydrogen production in single-chamber tubular microbial electrolysis cells using non-precious-metal catalysts

    E-Print Network [OSTI]

    Tullos, Desiree

    Hydrogen production in single-chamber tubular microbial electrolysis cells using non August 2009 Keywords: Hydrogen production Microbial electrolysis cells (MECs) NiMo NiW Cathode catalystMo cathode accomplished a hydrogen production rate of 2.0 m3 /day/m3 at current density of 270 A/m3 (12 A/m2

  9. A high-resolution drift chamber for Alpha-particle position measurements

    E-Print Network [OSTI]

    Oliver, Jon Patrick

    1996-01-01T23:59:59.000Z

    A drift chamber module with 5 anode wires covering an active region of 9 cm x 76 cm has been built to locate the vertical position of a-particle trajectories to within 295 mm full-width-half-maximum (FWEM) in isobutane at a pressure of 0.25 atm...

  10. Anode supported single chamber solid oxide fuel cells operating in exhaust gases of thermal engine

    E-Print Network [OSTI]

    Boyer, Edmond

    Anode supported single chamber solid oxide fuel cells operating in exhaust gases of thermal engine. Conventional solid oxide fuel cells are separated into two compartments containing each electrode split hydrocarbons, pollutant emissions reduction hal-01056363,version1-21Aug2014 #12;1. Introduction Solid oxide

  11. Report on Fission Time Projection Chamber M3FT-12IN0210052

    SciTech Connect (OSTI)

    James K. Jewell

    2012-08-01T23:59:59.000Z

    The Time Projection Chamber is a collaborative effort to implement an innovative approach and deliver unprecedented fission measurements to DOE programs. This 4?-detector system will provide unrivaled 3-D data about the fission process. Shown here is a half populated TPC (2?) at the LLNL TPC laboratory as it undergoes testing before being shipped to LANSCE for beam experiments.

  12. Assessment of the high temperature fission chamber technology for the French fast reactor program

    SciTech Connect (OSTI)

    Jammes, C.; Filliatre, P.; Geslot, B.; Domenech, T.; Normand, S. [Commissariat a l'Energie Atomique, CEA (France)

    2011-07-01T23:59:59.000Z

    High temperature fission chambers are key instruments for the control and protection of the sodium-cooled fast reactor. First, the developments of those neutron detectors, which are carried out either in France or abroad are reviewed. Second, the French realizations are assessed with the use of the technology readiness levels in order to identify tracks of improvement. (authors)

  13. Increased performance of single-chamber microbial fuel cells using an improved cathode structure

    E-Print Network [OSTI]

    Increased performance of single-chamber microbial fuel cells using an improved cathode structure Maximum power densities by air-driven microbial fuel cells (MFCs) are considerably influenced by cathode reserved. Keywords: Microbial fuel cell; Air cathode; Diffusion layer; PTFE coating; Coulombic efficiency 1

  14. Neutronics Assessment of Blanket Options for the HAPL Laser Inertial Fusion Energy Chamber

    E-Print Network [OSTI]

    Raffray, A. René

    -cooled lithium blanket, a helium-cooled solid breeder blanket, and a dual-coolant lithium lead blanket of the reference blanket. Keywords-Laser fusion; lithium blanket; solid breeder; lithium lead; tritium breedingNeutronics Assessment of Blanket Options for the HAPL Laser Inertial Fusion Energy Chamber M

  15. Development of fast heating electron beam annealing setup for ultra high vacuum chamber

    SciTech Connect (OSTI)

    Das, Sadhan Chandra [UGC-DAE Consortium For Scientific Research, University Campus, Khandwa Road, Indore 452 001, MP (India) [UGC-DAE Consortium For Scientific Research, University Campus, Khandwa Road, Indore 452 001, MP (India); School of Electronics, Devi Ahilya University, Indore 452001, MP (India); Institute of Physics, University of Greifswald, Felix Hausdroff Str. 6 (Germany); Majumdar, Abhijit, E-mail: majuabhijit@gmail.com, E-mail: majumdar@uni-greifswald.de; Hippler, R. [Institute of Physics, University of Greifswald, Felix Hausdroff Str. 6 (Germany)] [Institute of Physics, University of Greifswald, Felix Hausdroff Str. 6 (Germany); Katiyal, Sumant [School of Electronics, Devi Ahilya University, Indore 452001, MP (India)] [School of Electronics, Devi Ahilya University, Indore 452001, MP (India); Shripathi, T. [UGC-DAE Consortium For Scientific Research, University Campus, Khandwa Road, Indore 452 001, MP (India)] [UGC-DAE Consortium For Scientific Research, University Campus, Khandwa Road, Indore 452 001, MP (India)

    2014-02-15T23:59:59.000Z

    We report the design and development of a simple, electrically low powered and fast heating versatile electron beam annealing setup (up to 1000?°C) working with ultra high vacuum (UHV) chamber for annealing thin films and multilayer structures. The important features of the system are constant temperature control in UHV conditions for the temperature range from room temperature to 1000?ºC with sufficient power of 330 W, at constant vacuum during annealing treatment. It takes approximately 6 min to reach 1000?°C from room temperature (?10{sup ?6} mbar) and 45 min to cool down without any extra cooling. The annealing setup consists of a UHV chamber, sample holder, heating arrangement mounted on suitable UHV electrical feed-through and electronic control and feedback systems to control the temperature within ±1?ºC of set value. The outside of the vacuum chamber is cooled by cold air of 20?°C of air conditioning machine used for the laboratory, so that chamber temperature does not go beyond 50?°C when target temperature is maximum. The probability of surface oxidation or surface contamination during annealing is examined by means of x-ray photoelectron spectroscopy of virgin Cu sample annealed at 1000?°C.

  16. Transient blocking in multi-chamber natural ventilation M. R. Flynn and C. P. Caulfield

    E-Print Network [OSTI]

    Flynn, Morris R.

    , the system must evolve towards a ventilated terminal state in which there is outflow of buoyant fluid (inflowTransient blocking in multi-chamber natural ventilation M. R. Flynn and C. P. Caulfield Dept-energy `natural' ventilation offers an environmental benefit over building ventilation by high

  17. Chamber Technology Goals Used in APEX to Calibrate New Ideas and Measure Progress

    E-Print Network [OSTI]

    Abdou, Mohamed

    Chamber Technology Goals Used in APEX to Calibrate New Ideas and Measure Progress 1. High Power a subset will be remarkable progress for fusion #12;Innovative concepts proposed by APEX can extend Alloys evaluated: W-alloy selected ·Helium cooling and Li boiling evaluated ·SiC/SiC-LiPb limits

  18. Numerical Analysis of a one dimensional Diffusion Equation for a single chamber Microbial Fuel Cell using

    E-Print Network [OSTI]

    dimensional Diffusion Equation to model oxygen in a single chamber MFC. A rigorous verification of the effects . . . . . . . . . . . . . . . . . . 12 5 Model Application 13 #12;Advanced Numerical Methods Zielke iii 5.1 System Configuration May 5, 2006 #12;Abstract Renewable energy (RE) applications are becoming a popular means of power

  19. Multi-property characterization chamber for geophysical-hydrological investigations of hydrate bearing sediments

    SciTech Connect (OSTI)

    Seol, Yongkoo, E-mail: Yongkoo.Seol@netl.doe.gov; Choi, Jeong-Hoon; Dai, Sheng [National Energy Technology Laboratory, U.S. Department of Energy, Morgantown, West Virginia 26507 (United States)

    2014-08-01T23:59:59.000Z

    With the increase in the interest of producing natural gas from methane hydrates as well as potential risks of massive hydrate dissociation in the context of global warming, studies have recently shifted from pure hydrate crystals to hydrates in sediments. Such a research focus shift requires a series of innovative laboratory devices that are capable of investigating various properties of hydrate-bearing sediments (HBS). This study introduces a newly developed high pressure testing chamber, i.e., multi-property characterization chamber (MPCC), that allows simultaneous investigation of a series of fundamental properties of HBS, including small-strain stiffness (i.e., P- and S-waves), shear strength, large-strain deformation, stress-volume responses, and permeability. The peripheral coolant circulation system of the MPCC permits stable and accurate temperature control, while the core holder body, made of aluminum, enables X-ray computer tomography scanning to be easily employed for structural and morphological characterization of specimens. Samples of hydrate-bearing sediments are held within a rubber sleeve inside the chamber. The thick sleeve is more durable and versatile than thin membranes while also being much softer than oedometer-type chambers that are incapable of enabling flow tests. Bias introduced by the rubber sleeve during large deformation tests are also calibrated both theoretically and experimentally. This system provides insight into full characterization of hydrate-bearing sediments in the laboratory, as well as pressure core technology in the field.

  20. Four-Button BPM Coefficients in Cylindrical and Elliptic Beam Chambers February 17, 1999

    E-Print Network [OSTI]

    Kemner, Ken

    Four-Button BPM Coefficients in Cylindrical and Elliptic Beam Chambers S. H. Kim February 17, 1999 Beam position monitor (BPM) coefficients are calculated from induced charges on four-button BPMs ring is different from an exact elliptic geometry, numerical values of the BPM coefficients

  1. ForPeerReview A climate-controlled whole-tree chamber system

    E-Print Network [OSTI]

    Boyer, Edmond

    to impose combinations of atmospheric carbon dioxide concentra- tion, [CO2], and air temperature treatments in the ambient [CO2] chambers was too low to be maintained during winter because of tree dormancy and the high natural increase in [CO2] over winter at high latitudes such as the Flakaliden site. Accurate control over

  2. Geothermally heated Chamber of Commerce offices at Marlin, Texas. Final report

    SciTech Connect (OSTI)

    Not Available

    1981-07-31T23:59:59.000Z

    The use of an existing, low temperature, geothermal resource to heat the Chamber of Commerce offices in Marlin, Texas is described. A secondary purpose of the project is to attract new industries and businesses to Marlin via this alternate energy show-piece demonstration of a simple and practical application of Texas' low temperature geothermal resource.

  3. THERMO FLUID DYNAMICS AND CHAMBER AEROSOL BEHAVIOR FOR THIN LIQUID WALL UNDER IFE

    E-Print Network [OSTI]

    control. In determining the con- ditions of the chamber gas and0or vapor prior to each shot, and condensation to the wall. These issues were analyzed in detail as part of the ARIES-IFE study3 for different formation are discussed. A scoping analysis

  4. Determing Degradation Of Fiberboard In The 9975 Shipping Package By Measuring Axial Gap

    SciTech Connect (OSTI)

    Hackney, E. R.; Dougherty, W. L.; Dunn, K. A.; Stefek, T. M

    2013-08-01T23:59:59.000Z

    Currently, thousands of model 9975 transportation packages are in use by the US Department of Energy (DOE); the design of which has been certified by DOE for shipment of Type B radioactive and fissile materials in accordance with Part 71, Title 10 Code of Federal Regulations (CFR), or 10 CFR 71, Packaging and Transportation of Radioactive Material. These transportation packages are also approved for the storage of DOE-STD-3013 containers at the Savannah River Site (SRS). As such, the 9975 has been continuously exposed to the service environment for a period of time greater than the approved transportation service life. In order to ensure the material integrity as specified in the safety basis, an extensive surveillance program is in place in K-Area Complex (KAC) to monitor the structural and thermal properties of the fiberboard of the 9975 shipping packages. The surveillance approach uses a combination of Non-Destructive Examination (NDE) field surveillance and Destructive Examination (DE) lab testing to validate the 9975 performance assumptions. The fiberboard in the 9975 is credited with thermal insulation, criticality control and resistance to crushing. During surveillance monitoring in KAC, an increased axial gap of the fiberboard was discovered on selected items packaged at Rocky Flats Environmental Technology Site (RFETS). Many of these packages were later found to contain excess moisture. Savannah River National Laboratory (SRNL) testing has resulted in a better understanding of the relationship between the fiberboard moisture level and compaction of the fiberboard under storage conditions and during transport. In laboratory testing, the higher moisture content has been shown to correspond to higher total compaction of fiberboard material and compaction rate. The fiberboard height is reduced by compression of the layers. This change is observed directly in the axial gap between the flange and the air shield. The axial gap measurement is made during the pre-use inspection or during the annual recertification process and is a screening measurement for changes in the fiberboard.

  5. Determination of the Axial-Vector Weak Coupling Constant with Ultracold Neutrons

    E-Print Network [OSTI]

    UCNA Collaboration; J. Liu; M. P. Mendenhall; A. T. Holley; H. O. Back; T. J. Bowles; L. J. Broussard; R. Carr; S. Clayton; S. Currie; B. W. Filippone; A. Garcia; P. Geltenbort; K. P. Hickerson; J. Hoagland; G. E. Hogan; B. Hona; T. M. Ito; C. -Y. Liu; M. Makela; R. R. Mammei; J. W. Martin; D. Melconian; C. L. Morris; R. W. Pattie Jr.; A. Perez Galvan; M. L. Pitt; B. Plaster; J. C. Ramsey; R. Rios; R. Russell; A. Saunders; S. J. Seestrom; W. E. Sondheim; E. Tatar; R. B. Vogelaar; B. VornDick; C. Wrede; H. Yan; A. R. Young

    2010-09-25T23:59:59.000Z

    A precise measurement of the neutron decay $\\beta$-asymmetry $A_0$ has been carried out using polarized ultracold neutrons (UCN) from the pulsed spallation UCN source at the Los Alamos Neutron Science Center (LANSCE). Combining data obtained in 2008 and 2009, we report $A_0 = -0.11966 \\pm 0.00089_{-0.00140}^{+0.00123}$, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon $g_A/g_V = -1.27590_{-0.00445}^{+0.00409}$.

  6. Determination of the Axial-Vector Weak Coupling Constant with Polarized Ultracold Neutrons

    E-Print Network [OSTI]

    Liu, J; Holley, A T; Back, H O; Bowles, T J; Broussard, L J; Carr, R; Clayton, S; Currie, S; Filippone, B W; Garcia, A; Geltenbort, P; Hickerson, K P; Hoagland, J; Hogan, G E; Hona, B; Ito, T M; Liu, C -Y; Makela, M; Mammei, R R; Martin, J W; Melconian, D; Morris, C L; Pattie, R W; Galvan, A Perez; Pitt, M L; Plaster, B; Ramsey, J C; Rios, R; Russell, R; Saunders, A; Seestrom, S; Sondheim, W E; Tatar, E; Vogelaar, R B; VornDick, B; Wrede, C; Yan, H; Young, A R

    2010-01-01T23:59:59.000Z

    A precise measurement of the neutron decay $\\beta$-asymmetry $A_0$ has been carried out using polarized ultracold neutrons (UCN) from the pulsed spallation UCN source at the Los Alamos Neutron Science Center (LANSCE). Combining data obtained in 2008 and 2009, we report $A_0 = -0.11966 \\pm 0.00089 _{-0.00140}^{+0.00123}$, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon $g_A/g_V = -1.27590 _{-0.00445}^{+0.00409}$.

  7. Spatiotemporal evolution of ponderomotive electron heating in axially inhomogeneous collisionless plasma

    SciTech Connect (OSTI)

    Mishra, S. K. [Institute for Plasma Research (IPR), Gandhinagar (India)] [Institute for Plasma Research (IPR), Gandhinagar (India); Sharma, A. [Institute of Physics, University of Pecs, Pecs 7624 (Hungary)] [Institute of Physics, University of Pecs, Pecs 7624 (Hungary)

    2013-07-15T23:59:59.000Z

    We investigate the spatiotemporal focusing dynamics of a Gaussian laser pulse in preformed collisionless plasma subjected to an axial nonuniformity in the plasma density. In order to follow up the pulse dynamics, a nonlinear Schrödinger wave equation characterizing the beam spot size in space and time frame has been derived and solved numerically to investigate the propagation characteristics as the pulse advances in the plasma. The effect of inhomogeneity on focusing length and ponderomotive electron heating have been analyzed and illustrated graphically. It is seen that ponderomotive heating is quite sensitive to the inhomogeneity parameters and the energy gain by electrons can be optimized by suitable choice of parameters.

  8. Axial force imparted by a conical radiofrequency magneto-plasma thruster

    SciTech Connect (OSTI)

    Charles, C.; Takahashi, K.; Boswell, R. W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, ACT 0200 (Australia)

    2012-03-12T23:59:59.000Z

    Direct thrust measurements of a low pressure ({approx}0.133 Pa) conical radiofrequency (rf at 13.56 MHz) argon plasma source show a total axial force of about 5 mN for an effective rf power of 650 W and a maximum magnetic field of 0.018 T, of which a measured value of 2.5 mN is imparted by the magnetic nozzle. A simplified model of thrust including contributions from the electron pressure and from the magnetic field pressure is developed. The magnetic nozzle is modelled as a ''physical'' nozzle of increasing cross-sectional area.

  9. Probabilistic Analysis of a Monod-type equation by use of a single chamber Microbial Fuel Cell

    E-Print Network [OSTI]

    Probabilistic Analysis of a Monod-type equation by use of a single chamber Microbial Fuel Cell Eric for our society. Microbial fuel cells (MFCs) represent a new form of renewable energy by converting of a single chamber Microbial Fuel Cell affect the power density produced in the Microbial Fuel Cell

  10. Anode-supported thin-film fuel cells operated in a single chamber configuration 2T-I-12

    E-Print Network [OSTI]

    Haile, Sossina M.

    on the anode, producing a complex response in fuel cell power output. Under optimized gas compositions and flowAnode-supported thin-film fuel cells operated in a single chamber configuration 2T-I-12 Zongping of anode-supported, thin-film, single chamber fuel cells (SCFCs) have been investigated. Cells, in which Ni

  11. LIFE Chamber Chemical Equilibrium Simulations with Additive Hydrogen, Oxygen, and Nitrogen

    SciTech Connect (OSTI)

    DeMuth, J A; Simon, A J

    2009-09-03T23:59:59.000Z

    In order to enable continuous operation of a Laser Inertial confinement Fusion Energy (LIFE) engine, the material (fill-gas and debris) in the fusion chamber must be carefully managed. The chamber chemical equilibrium compositions for post-shot mixtures are evaluated to determine what compounds will be formed at temperatures 300-5000K. It is desired to know if carbon and or lead will deposit on the walls of the chamber, and if so: at what temperature, and what elements can be added to prevent this from happening. The simulation was conducted using the chemical equilibrium solver Cantera with a Matlab front-end. Solutions were obtained by running equilibrations at constant temperature and constant specific volume over the specified range of temperatures. It was found that if nothing is done, carbon will deposit on the walls once it cools to below 2138K, and lead below 838K. Three solutions to capture the carbon were found: adding pure oxygen, hydrogen/nitrogen combo, and adding pure nitrogen. The best of these was the addition of oxygen which would readily form CO at around 4000K. To determine the temperature at which carbon would deposit on the walls, temperature solutions to evaporation rate equations needed to be found. To determine how much carbon or any species was in the chamber at a given time, chamber flushing equations needed to be developed. Major concerns are deposition of carbon and/or oxygen on the tungsten walls forming tungsten oxides or tungsten carbide which could cause embrittlement and cause failure of the first wall. Further research is needed.

  12. Monte Carlo calculations for reference dosimetry of electron beams with the PTW Roos and NE2571 ion chambers

    SciTech Connect (OSTI)

    Muir, B. R., E-mail: bmuir@physics.carleton.ca; Rogers, D. W. O., E-mail: drogers@physics.carleton.ca [Physics Department, Carleton Laboratory for Radiotherapy Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)] [Physics Department, Carleton Laboratory for Radiotherapy Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)

    2013-12-15T23:59:59.000Z

    Purpose: To investigate recommendations for reference dosimetry of electron beams and gradient effects for the NE2571 chamber and to provide beam quality conversion factors using Monte Carlo simulations of the PTW Roos and NE2571 ion chambers. Methods: The EGSnrc code system is used to calculate the absorbed dose-to-water and the dose to the gas in fully modeled ion chambers as a function of depth in water. Electron beams are modeled using realistic accelerator simulations as well as beams modeled as collimated point sources from realistic electron beam spectra or monoenergetic electrons. Beam quality conversion factors are calculated with ratios of the doses to water and to the air in the ion chamber in electron beams and a cobalt-60 reference field. The overall ion chamber correction factor is studied using calculations of water-to-air stopping power ratios. Results: The use of an effective point of measurement shift of 1.55 mm from the front face of the PTW Roos chamber, which places the point of measurement inside the chamber cavity, minimizes the difference betweenR{sub 50}, the beam quality specifier, calculated from chamber simulations compared to that obtained using depth-dose calculations in water. A similar shift minimizes the variation of the overall ion chamber correction factor with depth to the practical range and reduces the root-mean-square deviation of a fit to calculated beam quality conversion factors at the reference depth as a function of R{sub 50}. Similarly, an upstream shift of 0.34 r{sub cav} allows a more accurate determination of R{sub 50} from NE2571 chamber calculations and reduces the variation of the overall ion chamber correction factor with depth. The determination of the gradient correction using a shift of 0.22 r{sub cav} optimizes the root-mean-square deviation of a fit to calculated beam quality conversion factors if all beams investigated are considered. However, if only clinical beams are considered, a good fit to results for beam quality conversion factors is obtained without explicitly correcting for gradient effects. The inadequacy of R{sub 50} to uniquely specify beam quality for the accurate selection of k{sub Q} factors is discussed. Systematic uncertainties in beam quality conversion factors are analyzed for the NE2571 chamber and amount to between 0.4% and 1.2% depending on assumptions used. Conclusions: The calculated beam quality conversion factors for the PTW Roos chamber obtained here are in good agreement with literature data. These results characterize the use of an NE2571 ion chamber for reference dosimetry of electron beams even in low-energy beams.

  13. Fracture analysis of axially cracked pressure tube of pressurized heavy water reactor

    SciTech Connect (OSTI)

    Krishnan, S.; Bhasin, V.; Mahajan, S.C. [Bhabha Atomic Research Centre, Bombay (India)] [and others

    1997-04-01T23:59:59.000Z

    Three Dimensional (313) finite element elastic plastic fracture analysis was done for through wall axially cracked thin pressure tubes of 220 MWe Indian Pressurized Heavy Water Reactor. The analysis was done for Zr-2 and Zr-2.5Nb pressure tubes operating at 300{degrees}C and subjected to 9.5 Mpa internal pressure. Critical crack length was determined based on tearing instability concept. The analysis included the effect of crack face pressure due to the leaking fluid from tube. This effect was found to be significant for pressure tubes. The available formulae for calculating J (for axially cracked tubes) do not take into account the effect of crack face pressure. 3D finite element analysis also gives insight into variation of J across the thickness of pressure tube. It was observed that J is highest at the mid-surface of tube. The results have been presented in the form of across the thickness average J value and a peak factor on J. Peak factor on J is ratio of J at mid surface to average J value. Crack opening area for different cracked lengths was calculated from finite element results. The fracture assessment of pressure tubes was also done using Central Electricity Generating Board R-6 method. Ductile tearing was considered.

  14. Broken axial symmetry as essential feature to predict radiative capture in heavy nuclei

    E-Print Network [OSTI]

    Grosse, Eckart; Massarczyk, Ralph

    2014-01-01T23:59:59.000Z

    Cross sections for neutron capture in the range of unresolved resonances are predicted for more than 140 spin-0 target nuclei with A > 50. Allowing the breaking of spherical and axial symmetry in nearly all these nuclei a combined parameterization for both, level density and photon strength is obtained which employs a surprisingly small number of parameters only. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians. They are based on theoretical predictions for the A-dependence of pole energies and spreading widths and add up to the TRK sum rule. For the small spins reached by capture resonance spacings are well described by a level density parameter close to the nuclear matter value; a significant collective enhancement is apparent due to the deviation from axial symmetry. Reliable predictions for compound nuclear reactions also outside the valley of stability (as important for nuclear astrophysics and for the transmutation of nuclear waste) are expected to re...

  15. Broken axial symmetry as essential feature to predict radiative capture in heavy nuclei

    E-Print Network [OSTI]

    Eckart Grosse; Arnd R. Junghans; Ralph Massarczyk

    2015-01-14T23:59:59.000Z

    Cross sections for neutron capture in the range of unresolved resonances are predicted for more than 140 spin-0 target nuclei with A > 50. Allowing the breaking of spherical and axial symmetry in nearly all these nuclei a combined parameterization for both, level density and photon strength is obtained which employs a surprisingly small number of parameters only. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians. They are based on theoretical predictions for the A-dependence of pole energies and spreading widths and add up to the TRK sum rule. For the small spins reached by capture resonance spacings are well described by a level density parameter close to the nuclear matter value; a significant collective enhancement is apparent due to the deviation from axial symmetry. Reliable predictions for compound nuclear reactions also outside the valley of stability (as important for nuclear astrophysics and for the transmutation of nuclear waste) are expected to result from the global parameterization presented.

  16. Evaporative capillary instability for flow in porous media under the influence of axial electric field

    SciTech Connect (OSTI)

    Kumar Awasthi, Mukesh, E-mail: mukeshiitr.kumar@gmail.com [Department of Mathematics, University of Petroleum and Energy Studies, Dehradun (India)

    2014-04-15T23:59:59.000Z

    We study the linear analysis of electrohydrodynamic capillary instability of the interface between two viscous, incompressible and electrically conducting fluids in a fully saturated porous medium, when the phases are enclosed between two horizontal cylindrical surfaces coaxial with the interface and, when there is mass and heat transfer across the interface. The fluids are subjected to a constant electric field in the axial direction. Here, we use an irrotational theory in which the motion and pressure are irrotational and the viscosity enters through the jump in the viscous normal stress in the normal stress balance at the interface. A quadratic dispersion relation that accounts for the growth of axisymmetric waves is obtained and stability criterion is given in terms of a critical value of wave number as well as electric field. It is observed that heat transfer has stabilizing effect on the stability of the considered system while medium porosity destabilizes the interface. The axial electric field has dual effect on the stability analysis.

  17. A two-dimensional (azimuthal-axial) particle-in-cell model of a Hall thruster

    SciTech Connect (OSTI)

    Coche, P.; Garrigues, L., E-mail: laurent.garrigues@laplace.univ-tlse.fr [LAPLACE (Laboratoire Plasma et Conversion d'Energie), Université de Toulouse, UPS, INPT Toulouse 118, route de Narbonne, F-31062 Toulouse cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France)

    2014-02-15T23:59:59.000Z

    We have developed a two-dimensional Particle-In-Cell model in the azimuthal and axial directions of the Hall thruster. A scaling method that consists to work at a lower plasma density to overcome constraints on time-step and grid-spacing is used. Calculations are able to reproduce the breathing mode due to a periodic depletion of neutral atoms without the introduction of a supplementary anomalous mechanism, as in fluid and hybrid models. Results show that during the increase of the discharge current, an electron-cyclotron drift instability (frequency in the range of MHz and wave number on the order of 3000 rad s{sup ?1}) is formed in the region of the negative gradient of magnetic field. During the current decrease, an axial electric wave propagates from the channel toward the exhaust (whose frequency is on the order of 400?kHz) leading to a broadening of the ion energy distribution function. A discussion about the influence of the scaling method on the calculation results is also proposed.

  18. Analysis Of Residence Time Distribution Of Fluid Flow By Axial Dispersion Model

    SciTech Connect (OSTI)

    Sugiharto [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia); Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Su'ud, Zaki; Kurniadi, Rizal; Waris, Abdul [Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Abidin, Zainal [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia)

    2010-12-23T23:59:59.000Z

    Radioactive tracer {sup 82}Br in the form of KBr-82 with activity {+-} 1 mCi has been injected into steel pipeline to qualify the extent dispersion of water flowing inside it. Internal diameter of the pipe is 3 in. The water source was originated from water tank through which the water flow gravitically into the pipeline. Two collimated sodium iodide detectors were used in this experiment each of which was placed on the top of the pipeline at the distance of 8 and 11 m from injection point respectively. Residence time distribution (RTD) curves obtained from injection of tracer are elaborated numerically to find information of the fluid flow properties. The transit time of tracer calculated from the mean residence time (MRT) of each RTD curves is 14.9 s, therefore the flow velocity of the water is 0.2 m/s. The dispersion number, D/uL, for each RTD curve estimated by using axial dispersion model are 0.055 and 0.06 respectively. These calculations are performed after fitting the simulated axial dispersion model on the experiment curves. These results indicated that the extent of dispersion of water flowing in the pipeline is in the category of intermediate.

  19. Measuring the axial form factor of {sup 3}He using weak capture of polarized electrons

    SciTech Connect (OSTI)

    Dutta, D. [Mississippi State University, Mississippi State, MS 39762 (United States)

    2013-11-07T23:59:59.000Z

    A low energy, high intensity polarized electron beam could enable the extraction of the A=3 weak axial form factors F{sub A} using the reaction ?e+{sup 3}He?{sup 3}H+?. These form factors have never been measured before. We discuss the feasibility of such an experiment using a small toroidal magnet and a radial low energy recoil detector to tag the recoil tritons. A moderately high intensity polarized electron beam (>500 ?A) with beam energies between 50 - 150 MeV is necessary for the cross section measurement and to provides a free clean measurement of the background. Moreover, in addition to the cross section, by measuring the electron spin and recoil triton correlation coefficient it may be possible to search for second class currents and to extract the ratio of the axial to the vector form factor of the nucleon. Such novel electron scattering based measurements would have a completely different set of systematic uncertainties compared to polarized neutron beta decay, neutrino scattering and muon capture experiments which are typically used to extract the weak form-factors.

  20. Clean measurements of the nucleon axial-vector and free-neutron magnetic form factors

    E-Print Network [OSTI]

    Alexandre Deur

    2014-07-21T23:59:59.000Z

    We discuss the feasibility of a weak charged current experiment using a low energy electron beam. A first goal is to measure the Q^2 dependence of the axial-vector form factor g_a(Q^2). It can be measured model-independently and as robustly as for electromagnetic form factors from typical electron scattering experiments, in contrast to the methods used so far to measure g_a(Q^2). If g_a(Q^2) follows a dipole form, the axial mass can be extracted with a better accuracy than the world data altogether. The most important detection equipment would be a segmented neutron detector with good momentum and angular resolution that is symmetric about the beam direction, and covers a moderate angular range. A high intensity beam (100 uA) is necessary. Beam polarization is highly desirable as it provides a clean measurement of the backgrounds. Beam energies between 70 and 110 MeV are ideal. This range would provide a Q^2 mapping of g_a between 0.01

  1. Nickel based anodes for single chamber solid oxide fuel cells : a catalytic study Geoffroy Gadacz, Sorina Udroiu, Jean-Paul Viricelle, Christophe Pijolat, Michle Pijolat

    E-Print Network [OSTI]

    Boyer, Edmond

    Nickel based anodes for single chamber solid oxide fuel cells : a catalytic study Geoffroy Gadacz Single chamber solid oxide fuel cells (SCFC) are an alternative concept to traditional SOFC

  2. To do list for laser maintenance 8.28-8.30 1. Clean the turning box and compressor chamber, remove all broken glass piece on bread board

    E-Print Network [OSTI]

    Shvets, Gennady

    and compressor chamber, remove all broken glass piece on bread board and mirror mount all optics in turning box and compressor chamber, replace all optics with damage spots on it, measure the reflectivity of compressor. 4. Check focal spot

  3. Natural Circulation and Linear Stability Analysis for Liquid-Metal Reactors with the Effect of Fluid Axial Conduction

    SciTech Connect (OSTI)

    Piyush Sabharwall; Qiao Wu; James J. Sienicki

    2012-06-01T23:59:59.000Z

    The effect of fluid axial thermal conduction on one-dimensional liquid metal natural circulation and its linear stability was performed through nondimensional analysis, steady-state assessment, and linear perturbation evaluation. The Nyquist criterion and a root-search method were employed to find the linear stability boundary of both forward and backward circulations. The study provided a relatively complete analysis method for one-dimensional natural circulation problems with the consideration of fluid axial heat conduction. The results suggest that fluid axial heat conduction in a natural circulation loop should be considered only when the modified Peclet number is {approx}1 or less, which is significantly smaller than the practical value of a lead liquid metal-cooled reactor.

  4. IFE Final Optics and Chamber Dynamics Modeling and Experiments Final Technical Report

    SciTech Connect (OSTI)

    F. Najmabadi; M. S. Tillack

    2006-01-11T23:59:59.000Z

    Our OFES-sponsored research on IFE technology originally focused on studies of grazing-incidence metal mirrors (GIMM's). After the addition of GIMM research to the High Average Power Laser (HAPL) program, our OFES-sponsored research evolved to include laser propagation studies, surface material evolution in IFE wetted-wall chambers, and magnetic intervention. In 2003, the OFES IFE Technology program was terminated. We continued to expend resources on a no-cost extension in order to complete student research projects in an orderly way and to help us explore new research directions. Those explorations led to funding in the field of extreme ultraviolet lithography, which shares many issues in common with inertial fusion chambers, and the field of radiative properties of laser-produced plasma.

  5. Overview of IFE chamber and target technologies R&D in the U.S.

    SciTech Connect (OSTI)

    Meier, W R; Abdou, M A; Kulcinski, G L; Moir, R W; Nobile, A; Peterson, P F; Petti, D A; Schultz, K R; Tillack, M S; Yoda, M

    2000-09-22T23:59:59.000Z

    The U.S. Department of Energy, Office of Fusion Energy Science (OFES) formed the Virtual Laboratory for Technology (VLT) to develop the technologies needed to support near term fusion experiments and to provide the basis for future magnetic and inertial fusion energy power plants. The scope of the inertial fusion energy (IFE) element of the VLT includes the fusion chamber, driver/chamber interface, target fabrication and injection, and safety and environmental assessment for IFE. Lawrence Livermore National Laboratory, in conjunction with other laboratories, universities and industry, has written an R&D plan to address the critical issues in these areas over the next 5 years in a coordinated manner. This paper provides an overview of the US. research activities addressing these critical issues.

  6. Acoustic studies for alpha background rejection in dark matter bubble chamber detectors

    SciTech Connect (OSTI)

    Bou-Cabo, M.; Felis, I.; Ardid, M.; Collaboration: COUPP Collaboration

    2013-08-08T23:59:59.000Z

    COUPP (Chicagoland Observatory for Underground Particle Physics) is an experiment with bubble chambers able to detect dark matter directly either with Spin-Dependent or with Spin-Independent interactions. The target material is a superheated liquid (usually CF3I) that can be bubble nucleated due to nuclear recoils produced by elastic collisions of dark matter particles. The bubble growth inside the chamber is accompanied with an acoustic signature. The acoustic technique has been successfully used to have a good alpha discrimination (about 99%). In this paper, we present different studies and results related with the characterization of the acoustic properties of the detector and the different phenomena involved in the acoustic measurements of the bubble growth, such as sound generation, sound transmission and optimization of piezoelectric transducers.

  7. Ion Chambers for Monitoring the NuMI Neutrino Beam at FNAL

    E-Print Network [OSTI]

    D. Indurthy; R. Keisler; S. Kopp; S. Mendoza; M. Proga; Z. Pavlovich; R. Zwaska; D. Harris; A. Marchionni; J. Morfin; A. Erwin; H. Ping; C. Velissaris; D. Naples; D. Northacker; J. McDonald; M. Diwan; B. Viren

    2004-05-05T23:59:59.000Z

    The Neutrinos at the Main Injector (NuMI) beamline will deliver an intense muon neutrino beam by focusing a beam of mesons into a long evacuated decay volume. The beam must be steered with 1 mRad angular accuracy toward the Soudan Underground Laboratory in northern Minnesota. We have built 4 arrays of ionization chambers to monitor the neutrino beam direction and quality. The arrays are located at 4 stations downstream of the decay volume, and measure the remnant hadron beam and tertiary muons produced along with neutrinos in meson decays. We review how the monitors will be used to make beam quality measurements, and as well we review chamber construction details, radiation damage testing, calibration, and test beam results.

  8. Addendum to the Technical Design Report for the Upgrade of the ALICE Time Projection Chamber

    E-Print Network [OSTI]

    The ALICE Collaboration

    2015-01-01T23:59:59.000Z

    This is the addendum to the TDR of the upgrade of the ALICE Time Projection Chamber (CERN-LHCC-2013-020 ; ALICE-TDR-016). The key objective of the upgrade is the replacement of the present MWPC-based readout chambers by detectors that allow continuous operation without active ion gating. In the TDR, we propose a solution that employs stacks of four Gas Electron Multipliers (GEMs) and demonstrate that it fulfills the design specifications, in particular in terms of intrinsic position resolution, energy resolution, and ion backflow. In this document we demonstrate with additional results from both detector R&D and simulations that the technological solution chosen in the TDR has sufficient safety margin for a successful campaign with the upgraded detector in RUN 3 and beyond.

  9. Neutron and gamma detector using an ionization chamber with an integrated body and moderator

    DOE Patents [OSTI]

    Ianakiev, Kiril D.; Swinhoe, Martyn T.; Lestone, John Paul

    2006-07-18T23:59:59.000Z

    A detector for detecting neutrons and gamma radiation includes a cathode that defines an interior surface and an interior volume. A conductive neutron-capturing layer is disposed on the interior surface of the cathode and a plastic housing surrounds the cathode. A plastic lid is attached to the housing and encloses the interior volume of the cathode forming an ionization chamber, into the center of which an anode extends from the plastic lid. A working gas is disposed within the ionization chamber and a high biasing voltage is connected to the cathode. Processing electronics are coupled to the anode and process current pulses which are converted into Gaussian pulses, which are either counted as neutrons or integrated as gammas, in response to whether pulse amplitude crosses a neutron threshold. The detector according to the invention may be readily fabricated into single or multilayer detector arrays.

  10. Direct Measurement of the Bubble Nucleation Energy Threshold in a CF3I Bubble Chamber

    E-Print Network [OSTI]

    Behnke, E; Brice, S J; Broemmelsiek, D; Collar, J I; Cooper, P S; Crisler, M; Dahl, C E; Fustin, D; Hall, J; Harnish, C; Levine, I; Lippincott, W H; Moan, T; Nania, T; Neilson, R; Ramberg, E; Robinson, A E; Sonnenschein, A; Vázquez-Jáuregui, E; Rivera, R A; Uplegger, L

    2013-01-01T23:59:59.000Z

    We have directly measured the energy threshold and efficiency for bubble nucleation from iodine recoils in a CF3I bubble chamber in the energy range of interest for a dark matter search. These interactions cannot be probed by standard neutron calibration methods, so we develop a new technique by observing the elastic scattering of 12 GeV/c negative pions. The pions are tracked with a silicon pixel telescope and the reconstructed scattering angle provides a measure of the nuclear recoil kinetic energy. The bubble chamber was operated with a nominal threshold of (13.6+-0.6) keV. Interpretation of the results depends on the response to fluorine and carbon recoils, but in general we find agreement with the predictions of the classical bubble nucleation theory. This measurement confirms the applicability of CF3I as a target for spin-independent dark matter interactions and represents a novel technique for calibration of superheated fluid detectors.

  11. MIMAC: MIcro-tpc MAtrix of Chambers for dark matter directional detection

    E-Print Network [OSTI]

    Santos, D; Bouly, J L; Bourrion, O; Fourel, Ch; Guillaudin, O; Lamblin, J; Mayet, F; Muraz, J F; Richer, J P; Riffard, Q; Lebreton, L; Maire, D; Busto, J; Brunner, J; Fouchez, D

    2013-01-01T23:59:59.000Z

    Directional detection of non-baryonic Dark Matter is a promising search strategy for discriminating WIMP events from neutrons, the ultimate background for dark matter direct detection. This strategy requires both a precise measurement of the energy down to a few keV and 3D reconstruction of tracks down to a few mm. The MIMAC (MIcro-tpc MAtrix of Chambers) collaboration has developed in the last years an original prototype detector based on the direct coupling of large pixelized micromegas with a special developed fast self-triggered electronics showing the feasibility of a new generation of directional detectors. The first bi-chamber prototype has been installed at Modane, underground laboratory in June 2012. The first undergournd background events, the gain stability and calibration are shown. The first spectrum of nuclear recoils showing 3D tracks coming from the radon progeny is presented.

  12. Plate Fin Heat Exchanger Model with Axial Conduction and Variable Properties

    SciTech Connect (OSTI)

    Hansen, B.J.; White, M.J.; Klebaner, A.; /Fermilab

    2011-06-10T23:59:59.000Z

    Future superconducting radio frequency (SRF) cavities, as part of Project X at Fermilab, will be cooled to superfluid helium temperatures by a cryogenic distribution system supplying cold supercritical helium. To reduce vapor fraction during the final Joule-Thomson (J-T) expansion into the superfluid helium cooling bath, counter-flow, plate-fin heat exchangers will be utilized. Due to their compact size and ease of fabrication, plate-fin heat exchangers are an effective option. However, the design of compact and high-effectiveness cryogenic heat exchangers operating at liquid helium temperatures requires consideration of axial heat conduction along the direction of flow, in addition to variable fluid properties. Here we present a numerical model that includes the effects of axial conduction and variable properties for a plate fin heat exchanger. The model is used to guide design decisions on heat exchanger material choice and geometry. In addition, the J-T expansion process is modeled with the heat exchanger to analyze the effect of heat load and cryogenic supply parameters. A numerical model that includes the effects of axial conduction and variable properties for a plate fin heat exchanger was developed and the effect of various design parameters on overall heat exchanger size was investigated. It was found that highly conductive metals should be avoided in the design of compact JT heat exchangers. For the geometry considered, the optimal conductivity is around 3.5 W/m-K and can range from 0.3-10 W/m-K without a large loss in performance. The model was implemented with an isenthalpic expansion process. Increasing the cold side inlet temperature from 2K to 2.2 K decreased the liquid fraction from 0.856 to 0.839 which corresponds to a 0.12 g/s increase in supercritical helium supply needed to maintain liquid level in the cooling bath. Lastly, it was found that the effectiveness increased when the heat load was below the design value. Therefore, the heat exchanger should be sized on the high end of the required heat load.

  13. Apparatus for monitoring tritium in tritium-contaminating environments using a modified Kanne chamber

    DOE Patents [OSTI]

    Anderson, D.F.

    1981-01-27T23:59:59.000Z

    A conventional Kanne tritium monitor has been redesigned to reduce its sensitivity to such contaminants as tritiated water vapor and tritiated oil. The high voltage electrode has been replaced by a wire cylinder and the collector electrode has been reduced in diameter. The area sensitive to contamination has thereby been reduced by about a factor of forty while the overall apparatus sensitivity and operation has not been affected. The design allows for in situ decontamination of the chambers, if necessary.

  14. Apparatus for monitoring tritium in tritium contaminating environments using a modified Kanne chamber

    DOE Patents [OSTI]

    Anderson, David F. (Los Alamos, NM)

    1984-01-01T23:59:59.000Z

    A conventional Kanne tritium monitor has been redesigned to reduce its sensitivity to such contaminants as tritiated water vapor and tritiated oil. The high voltage electrode has been replaced by a wire cylinder and the collector electrode has been reduced in diameter. The area sensitive to contamination has thereby been reduced by about a factor of forty while the overall apparatus sensitivity and operation has not been affected. The design allows for in situ decontamination of the chambers, if necessary.

  15. A Multiwire Proportional Chamber for Precision Studies of Neutron Beta Decay Angular Correlations

    E-Print Network [OSTI]

    Ito, T M; Filippone, B W; Martin, J W; Plaster, B; Rybka, G; Yuan, J; 10.1016/j.nima.2006.11.026

    2008-01-01T23:59:59.000Z

    A new multiwire proportional chamber (MWPC) was designed and constructed for precision studies of neutron beta decay angular correlations. Its design has several novel features, including the use of low pressure neopentane as the MWPC gas and an entrance window made of thin Mylar sheet reinforced with Kevlar fibers. In the initial off-line performance tests, the gas gain of neopentane and the position resolution were studied.

  16. A Multiwire Proportional Chamber for Precision Studies of Neutron Beta Decay Angular Correlations

    E-Print Network [OSTI]

    T. M. Ito; R. Carr; B. W. Filippone; J. W. Martin; B. Plaster; G. Rybka; J. Yuan

    2007-02-10T23:59:59.000Z

    A new multiwire proportional chamber (MWPC) was designed and constructed for precision studies of neutron beta decay angular correlations. Its design has several novel features, including the use of low pressure neopentane as the MWPC gas and an entrance window made of thin Mylar sheet reinforced with Kevlar fibers. In the initial off-line performance tests, the gas gain of neopentane and the position resolution were studied.

  17. Efficiency determination of resistive plate chambers for fast quasi-monoenergetic neutrons

    E-Print Network [OSTI]

    M. Röder; Z. Elekes; T. Aumann; D. Bemmerer; K. Boretzky; C. Caesar; T. E. Cowan; J. Hehner; M. Heil; M. Kempe; V. Maroussov; O. Nusair; A. V. Prokofiev; R. Reifarth; M. Sobiella; D. Stach; A. Wagner; D. Yakorev; A. Zilges; K. Zuber

    2014-07-10T23:59:59.000Z

    Composite detectors made of stainless steel converters and multigap resistive plate chambers have been irradiated with quasi-monoenergetic neutrons with a peak energy of 175MeV. The neutron detection efficiency has been determined using two different methods. The data are in agreement with the output of Monte Carlo simulations. The simulations are then extended to study the response of a hypothetical array made of these detectors to energetic neutrons from a radioactive ion beam experiment.

  18. Nucleon and Delta axial-vector couplings in 1/N{sub c}-Baryon Chiral Perturbation Theory

    SciTech Connect (OSTI)

    Goity, Jose Luis [JLAB; Calle Cordon, Alvaro [JLAB

    2013-08-01T23:59:59.000Z

    In this contribution, baryon axial-vector couplings are studied in the framework of the combined 1/N{sub c} and chiral expansions. This framework is implemented on the basis of the emergent spin-flavor symmetry in baryons at large N{sub c} and HBChPT, and linking both expansions ({xi}-expansion), where 1/N{sub c} is taken to be a quantity order p. The study is carried out including one-loop contributions, which corresponds to order xi to the third for baryon masses and order {xi} square for the axial couplings.

  19. Microwave electron cyclotron electron resonance (ECR) ion source with a large, uniformly distributed, axially symmetric, ECR plasma volume

    DOE Patents [OSTI]

    Alton, Gerald D. (Kingston, TN)

    1996-01-01T23:59:59.000Z

    An electron cyclotron resonance (ECR) ion source includes a primary mirror coil disposed coaxially around a vacuum vessel in which a plasma is induced and introducing a solenoidal ECR-producing field throughout the length of the vacuum vessel. Radial plasma confinement is provided by a multi-cusp, multi-polar permanent magnet array disposed azimuthally around the vessel and within the primary mirror coil. Axial confinement is provided either by multi-cusp permanent magnets at the opposite axial ends of the vessel, or by secondary mirror coils disposed on opposite sides of the primary coil.

  20. Polymer Growth Rate in a Wire Chamber with Oxygen,Water, or Alcohol Gas Additives

    SciTech Connect (OSTI)

    Boyarski, Adam; /SLAC

    2008-07-02T23:59:59.000Z

    The rate of polymer growth on wires was measured in a wire chamber while the chamber was aged initially with helium-isobutane (80:20) gas, and then with either oxygen, water, or alcohol added to the gas. At the completion of the aging process for each gas mixture, the carbon content on the wires was measured in a SEM/EDX instrument. The same physical wires were used in all the gas mixtures, allowing measurement of polymer build up or polymer depletion by each gas additive. It is found that the rate of polymer growth is not changed by the presence of oxygen, water or alcohol. Conjecture that oxygen reduces breakdown by removing polymer deposits on field wires is negated by these measurements. Instead, it appears that the reduced breakdown is due to lower resistance in the polymer from oxygen ions being transported into the polymer. It is also observed that field wires bombarded by the electrons in the SEM and then placed back into the chamber show an abundance of single electrons being emitted, indicating that electron charge is stored in the polymer layer and that a high electric field is necessary to remove the charge.

  1. Microwave remote plasma enhanced-atomic layer deposition system with multicusp confinement chamber

    SciTech Connect (OSTI)

    Dechana, A. [Program of Physics and General Science, Faculty of Science and Technology, Songkhla Rajabhat University, Songkhla 90000 (Thailand); Thamboon, P. [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50200 (Thailand); Boonyawan, D., E-mail: dheerawan.b@cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

    2014-10-15T23:59:59.000Z

    A microwave remote Plasma Enhanced-Atomic Layer Deposition system with multicusp confinement chamber is established at the Plasma and Beam Physics research facilities, Chiang Mai, Thailand. The system produces highly-reactive plasma species in order to enhance the deposition process of thin films. The addition of the multicusp magnetic fields further improves the plasma density and uniformity in the reaction chamber. Thus, the system is more favorable to temperature-sensitive substrates when heating becomes unwanted. Furthermore, the remote-plasma feature, which is generated via microwave power source, offers tunability of the plasma properties separately from the process. As a result, the system provides high flexibility in choice of materials and design experiments, particularly for low-temperature applications. Performance evaluations of the system were carried on coating experiments of Al{sub 2}O{sub 3} layers onto a silicon wafer. The plasma characteristics in the chamber will be described. The resulted Al{sub 2}O{sub 3} films—analyzed by Rutherford Backscattering Spectrometry in channeling mode and by X-ray Photoelectron Spectroscopy techniques—will be discussed.

  2. Interpretation of Secondary Organic Aerosol Formation from Diesel Exhaust Photooxidation in an Environmental Chamber

    SciTech Connect (OSTI)

    Nakao, Shunsuke; Shrivastava, ManishKumar B.; Nguyen, Anh; Jung, Hee-Jung; Cocker, David R.

    2011-04-14T23:59:59.000Z

    Secondary organic aerosol (SOA) formation from diesel exhaust in a smog chamber was investigated. Particle volume measurement based on mobility diameter is shown to underestimate SOA formation from diesel exhaust due to the external void space of agglomerate particles, in which case mass-based measurement technique is necessary. Rapid determination of particle effective density as a function of particle mass was performed by an Aerosol Particle Mass analyzer – Scanning Mobility Particle Sizer (APM-SMPS) to obtain particle mass concentration and fractal dimension. Continuous aging of aerosol was observed in terms of atomic ratio (O/C), from 0.05 to 0.25 in 12 hours, underscoring the importance of multi-generational oxidation of low-volatile organic vapors emitted from diesel engine as the significant source of oxygenated SOA. Experimental conditions possibly have strong impacts on physical evolution of diesel particulates in a smog chamber. Higher particle effective densities were observed when raw exhaust was injected into a full bag as opposed to filling a bag with diluted exhaust using an ejector diluter. When longer transfer line was used for injecting diesel exhaust into the smog chamber, rapid particle coagulation was observed, leading to increasing particle volume concentration in dark while its mass concentration is decreasing.

  3. Small-Chamber Measurements of Chemical-Specific Emission Factors for Drywall

    SciTech Connect (OSTI)

    Maddalena, Randy; Russell, Marion; Apte, Michael G.

    2010-06-01T23:59:59.000Z

    Imported drywall installed in U.S. homes is suspected of being a source of odorous and potentially corrosive indoor pollutants. To support an investigation of those building materials by the Consumer Products Safety Commission (CPSC), Lawrence Berkeley National Laboratory (LBNL) measured chemical-specific emission factors for 30 samples of drywall materials. Emission factors are reported for 75 chemicals and 30 different drywall samples encompassing both domestic and imported stock and incorporating natural, synthetic, or mixed gypsum core material. CPSC supplied all drywall materials. First the drywall samples were isolated and conditioned in dedicated chambers, then they were transferred to small chambers where emission testing was performed. Four sampling and analysis methods were utilized to assess (1) volatile organic compounds, (2) low molecular weight carbonyls, (3) volatile sulfur compounds, and (4) reactive sulfur gases. LBNL developed a new method that combines the use of solid phase microextraction (SPME) with small emission chambers to measure the reactive sulfur gases, then extended that technique to measure the full suite of volatile sulfur compounds. The testing procedure and analysis methods are described in detail herein. Emission factors were measured under a single set of controlled environmental conditions. The results are compared graphically for each method and in detailed tables for use in estimating indoor exposure concentrations.

  4. A Proposal to Operate the COUPP-60 Bubble Chamber at SNOLAB

    SciTech Connect (OSTI)

    Collar, Juan; Dahl, C.Eric; Fustin, Drew; Goetzke, Luke; Riley, Nathan; Schimmelpfennig, Hannes; Szydagis, Matthew; /KICP, Chicago; Behnke, Ed; Hinnefeld, Henry; Levine, Ilan; Palenchar, Andrea; /Indiana U., South Bend /Fermilab

    2009-08-01T23:59:59.000Z

    Bubble chambers are promising devices for the detection of WIMP dark matter, due to their easy scalability to large target masses and insensitivity to background {gamma} and {beta} radiation. The COUPP collaboration has constructed small chambers which have achieved competitive sensitivity for spin-dependent WIMP-nucleon scattering. A new chamber, COUPP-60, containing 60-kg of CF{sub 3}I target liquid, has been built and is being commissioned at Fermilab. We propose to move this detector to SNOLAB after completing tests in a shallow underground site at Fermilab. At SNOLAB, we expect the sensitivity of the experiment to be determined by the level of {alpha}emitting contamination in the target liquid. If we achieve state-of-the-art levels of {alpha} emitting contamination, we will improve current sensitivity by approximately four orders of magnitude beyond our published limits, to the region of 10{sup -4} pb for a 30 GeV WIMP interacting by spin-dependent couplings to the proton. This will allow a first exploration of the phase space favored by supersymmetric models in this regime.

  5. Comparative study of ionization chamber detectors vis-a-vis a CCD detector for dispersive XAS measurement in transmission geometry

    SciTech Connect (OSTI)

    Poswal, A. K.; Agrawal, A.; Bhattachryya, D.; Jha, S. N.; Sahoo, N. K. [Applied Spectroscopy Division, Bhabha Atomic Research Centre, Mumbai -400 085 (India)

    2013-02-05T23:59:59.000Z

    We have designed and fabricated parallel plate ionization chamber detectors and voltage vs. current characteristics (V-I curve) of the detectors were recorded with synchrotron radiation to qualify for use in X-ray Absorption Spectroscopy (XAS) measurements. After qualifying the ionization chambers, the detectors were used in the dispersive EXAFS beamline (BL-08) at INDUS-2 SRS in Turbo-XAS geometry. Using the same setup and under the same setting, XAS spectra were also recorded with a CCD detector and the observation on relative performance of the ionization chamber vis-a-vis the CCD detector is presented in this paper.

  6. Fig. 1. On the right is the Cloud Chamber, on the left is a laptop running the Cloud Catcher software ( Alexis Kirke.)

    E-Print Network [OSTI]

    Miranda, Eduardo Reck

    in real time. A glass cloud chamber was used onstage to make radioactivity visible in bright white tracksFig. 1. On the right is the Cloud Chamber, on the left is a laptop running the Cloud Catcher software (© Alexis Kirke.) CLOUD CHAMBER: A PERFORMANCE WITH REAL TIME TWO-WAY INTERACTION BETWEEN

  7. Axial force imparted by a current-free magnetically expanding plasma

    SciTech Connect (OSTI)

    Takahashi, Kazunori [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Department of Electrical Engineering and Computer Science, Iwate University, Morioka 020-8551 (Japan); Lafleur, Trevor; Charles, Christine; Alexander, Peter; Boswell, Rod W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia)

    2012-08-15T23:59:59.000Z

    The axial force imparted from a magnetically expanding, current-free, radiofrequency plasma is directly measured. For an argon gas flow rate of 25 sccm and an effective rf input power of {approx}800W, a maximum force of {approx}6mN is obtained; {approx}3mN of which is transmitted via the expanding magnetic field. The measured forces are reasonably compared with a simple fluid model associated with the measured electron pressure. The model suggests that the total force is the sum of an electron pressure inside the source and a Lorentz force due to the electron diamagnetic drift current and the applied radial magnetic field. It is shown that the Lorentz force is greatest near the magnetic nozzle surface where the radial pressure gradient is largest.

  8. Failure probability of axially cracked steam generator tubes; A probabilistic fracture mechanics model

    SciTech Connect (OSTI)

    Mavko, B.; Cizelj, L. (Jozef Stefan Inst., Reactor Engineering Div., P.O. Box 100, 61111 Ljubljana, Slovenia (YU))

    1992-05-01T23:59:59.000Z

    In this paper a model for estimating the failure probability of axially cracked steam generator tubes is proposed. The model compares observed crack length distribution with critical crack length distribution by means of probabilistic fracture mechanics. The observed crack length is influenced by measured data, measurement reliability, sizing accuracy, and predicted crack growth rate. The critical crack length is defined by a deterministic mechanical model. All cracks are conservatively assumed to extend through the tube wall. The effect of the plugging limit is studied along with the number of cracked tubes to perform risk-based lifetime optimization of steam generators. A numerical example presented considers hypothetical accidental operating conditions during a feedwater line break.

  9. A magnetic liquid deformable mirror for high stroke and low order axially symmetrical aberrations

    E-Print Network [OSTI]

    Brousseau, D; Parent, J; Ruel, H J; Borra, Ermanno F.; Brousseau, Denis; Parent, Jocelyn; Ruel, Hubert-Jean

    2006-01-01T23:59:59.000Z

    We present a new class of magnetically shaped deformable liquid mirrors made of a magnetic liquid (ferrofluid). Deformable liquid mirrors offer advantages with respect to deformable solid mirrors: large deformations, low costs and the possibility of very large mirrors with added aberration control. They have some disadvantages (e.g. slower response time). We made and tested a deformable mirror, producing axially symmetrical wavefront aberrations by applying electric currents to 5 concentric coils made of copper wire wound on aluminum cylinders. Each of these coils generates a magnetic field which combines to deform the surface of a ferrofluid to the desired shape. We have carried out laboratory tests on a 5 cm diameter prototype mirror and demonstrated defocus as well as Seidel and Zernike spherical aberrations having amplitudes up to 20 microns, which was the limiting measurable amplitude of our equipment

  10. A magnetic liquid deformable mirror for high stroke and low order axially symmetrical aberrations

    E-Print Network [OSTI]

    Denis Brousseau; Ermanno F. Borra; Hubert-Jean Ruel; Jocelyn Parent

    2006-11-15T23:59:59.000Z

    We present a new class of magnetically shaped deformable liquid mirrors made of a magnetic liquid (ferrofluid). Deformable liquid mirrors offer advantages with respect to deformable solid mirrors: large deformations, low costs and the possibility of very large mirrors with added aberration control. They have some disadvantages (e.g. slower response time). We made and tested a deformable mirror, producing axially symmetrical wavefront aberrations by applying electric currents to 5 concentric coils made of copper wire wound on aluminum cylinders. Each of these coils generates a magnetic field which combines to deform the surface of a ferrofluid to the desired shape. We have carried out laboratory tests on a 5 cm diameter prototype mirror and demonstrated defocus as well as Seidel and Zernike spherical aberrations having amplitudes up to 20 microns, which was the limiting measurable amplitude of our equipment

  11. Exponential Decay of Eigenfunctions and Accumulation of Eigenvalues on Manifolds with Axial Analytic Asymptotically Cylindrical Ends

    E-Print Network [OSTI]

    Victor Kalvin

    2010-07-25T23:59:59.000Z

    In this paper we continue our study of the Laplacian on manifolds with axial analytic asymptotically cylindrical ends initiated in~arXiv:1003.2538. By using the complex scaling method and the Phragm\\'{e}n-Lindel\\"{o}f principle we prove exponential decay of the eigenfunctions corresponding to the non-threshold eigenvalues of the Laplacian on functions. In the case of a manifold with (non-compact) boundary it is either the Dirichlet Laplacian or the Neumann Laplacian. We show that the rate of exponential decay of an eigenfunction is prescribed by the distance from the corresponding eigenvalue to the next threshold. Under our assumptions on the behaviour of the metric at infinity accumulation of isolated and embedded eigenvalues occur. The results on decay of eigenfunctions combined with the compactness argument due to Perry imply that the eigenvalues can accumulate only at thresholds and only from below. The eigenvalues are of finite multiplicity.

  12. Axial strain in GaAs/InAs core-shell nanowires

    SciTech Connect (OSTI)

    Biermanns, Andreas; Pietsch, Ullrich [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany)] [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany); Rieger, Torsten; Gruetzmacher, Detlev; Ion Lepsa, Mihail [Peter Gruenberg Institute (PGI-9), Forschungszentrum, 52425 Juelich (Germany) [Peter Gruenberg Institute (PGI-9), Forschungszentrum, 52425 Juelich (Germany); JARA-Fundamentals of Future Information Technology, 52425 Juelich (Germany); Bussone, Genziana [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany) [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany); ESRF, 6 rue Jules Horowitz, BP220, F-38043 Grenoble Cedex (France)

    2013-01-28T23:59:59.000Z

    We study the axial strain relaxation in GaAs/InAs core-shell nanowire heterostructures grown by molecular beam epitaxy. Besides a gradual strain relaxation of the shell material, we find a significant strain in the GaAs core, increasing with shell thickness. This strain is explained by a saturation of the dislocation density at the core-shell interface. Independent measurements of core and shell lattice parameters by x-ray diffraction reveal a relaxation of 93% in a 35 nm thick InAs shell surrounding cores of 80 nm diameter. The compressive strain of -0.5% compared to bulk InAs is accompanied by a tensile strain up to 0.9% in the GaAs core.

  13. Microscopic derivation of nuclear rotation-vibration model, axially symmetric case

    E-Print Network [OSTI]

    Gulshani, Parviz

    2015-01-01T23:59:59.000Z

    We derive from first principles the successful phenomenological hydrodynamic model of Bohr-Davydov-Faessler-Greiner for rotation-vibration motion of an axially symmetric deformed nucleus. The derivation is not limited to small oscillation amplitude, and provides microscopic expressions for the interaction operators among the rotation, vibration, and intrinsic motions, for the moment of inertia, vibration mass, and for the deformation variables. The method uses canonical transformations to collective co-ordinates, followed by a constrained variational method, with the associated constraints imposed on the wavefunction rather than on the particle co-ordinates. The approach yields three self-consistent, time-reversal invariant, cranking-type Schrodinger equations for the rotation-vibration and intrinsic motions, and a self-consistency equation. For deformed harmonic oscillator mean-field potentials, these equations are solved in closed forms for the energies, moments of inertia, quadrupole moments and transition...

  14. Hamiltonian dynamics of a symmetric top in external fields having axial symmetry. Levitating Orbitron

    E-Print Network [OSTI]

    Stanislav S. Zub; Sergiy I. Zub

    2015-02-13T23:59:59.000Z

    The symmetric top is a special case of the general top, and canonical Poisson structure on $T^*SE(3)$ is the common method of its description. This structure is invariant under the right action of $SO(3)$, but the Hamiltonian of the symmetric top is invariant only under the right action of subgroup $S^1$ that corresponds to the rotation around the symmetry axis of the symmetric top. So, its Poisson structure was obtained as the reduction $T^*SE(3)/S^1$. Next we propose the Hamiltonian that describes the wide class of the interaction models of symmetric top and axially-symmetric external field. The stability of the levitating Orbitron in relative equilibrium was proved.

  15. First-Forbidden beta decay Medium enhancement of the axial charge at A=16

    E-Print Network [OSTI]

    Warburton, E K; Brown, B A

    1994-01-01T23:59:59.000Z

    Calculations are presented for four relatively strong first-forbidden $\\beta$ decays in the region A=11-16 in order to study the very large mesonic-exchange-current enhancement of the rank-zero components. The $\\mu^-$ capture on $^{16}$O is considered on the same footing. The wave functions utilized include up to 4$\\hbar\\omega$ excitations. Two-body exchange-current matrix elements are calculated as well as one-body impulse approximation matrix elements. The resultant enhancement factor that multiplies the impulse-approximation axial-charge matrix element is thereby determined by comparison to experiment to be $\\epsilon_{exp}$ = 1.61 $\\pm$ 0.03 from three $\\beta^-$ decays and $\\mu^-$ capture on $^{16}$O, which is in excellent agreement with meson-exchange calculations in the soft-pion approximation.

  16. Cyclic powder formation during pulsed injection of hexamethyldisiloxane in an axially asymmetric radiofrequency argon discharge

    SciTech Connect (OSTI)

    Despax, B.; Makasheva, K. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse 09 (France); CNRS, LAPLACE, F-31062 Toulouse cedex 09 (France); Caquineau, H. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse 09 (France)

    2012-11-01T23:59:59.000Z

    A new approach of periodic production of dusty plasma consisting of pulsed injection of hexamethyldisiloxane (HMDSO) in argon axially asymmetric radiofrequency (RF) discharge was investigated in this work. The range of plasma operating conditions in which this dusty plasma can exist was closely examined. The obtained results clearly show that a net periodicity in the formation/disappearance of dust particles in the plasma can be maintained on a very large scale of discharge duration. The significance of discharge axial asymmetry to the dust particles behaviour in the plasma is revealed by the development of an asymmetric in shape void shifted towards the powered RF electrode. The key role of the reactive gas and its pulsed injection on each stage of the oscillating process of formation/disappearance of dust particles is disclosed by optical and electrical measurements. It is shown that the period of dusty plasma formation/disappearance is inversely related to the HMDSO injection time. Moreover, the impact of time injection over short period (5 s) is examined. It indicates the conflicting role played by the HMDSO on the reduction of dusty plasma during the reactive gas injection and the reappearance of particles in the plasma during the time off. The electronegative behavior of the plasma in the presence of negatively charged particles seems to explain the energetic modifications in the discharge. A frequency analysis of the floating potential reveals all these cyclic processes. Particularly, in the 10-200 Hz frequency range, the presence and the evolution of dust particles in the plasma over one generation can be observed.

  17. Isospin-invariant Skyrme energy-density-functional approach with axial symmetry

    E-Print Network [OSTI]

    J. A. Sheikh; N. Hinohara; J. Dobaczewski; T. Nakatsukasa; W. Nazarewicz; K. Sato

    2014-05-20T23:59:59.000Z

    We develop the isospin-invariant Skyrme-EDF method by considering local densities in all possible isospin channels and proton-neutron (p-n) mixing terms as mandated by the isospin symmetry. The EDF employed has the most general form that depends quadratically on the isoscalar and isovector densities. We test and benchmark the resulting p-n EDF approach, and study the general properties of the new scheme by means of the cranking in the isospin space. We extend the existing axial DFT solver HFBTHO to the case of isospin-invariant EDF approach with all possible p-n mixing terms. Explicit expressions have been derived for all the densities and potentials that appear in the isospin representation. In practical tests, we consider the Skyrme EDF SkM* and, as a first application, concentrate on Hartree-Fock aspects of the problem, i.e., pairing has been disregarded. Calculations have been performed for the (A=78, T~11), (A=40, T~8), and (A=48, T~4) isobaric analog chains. Isospin structure of self-consistent p-n mixed solutions has been investigated with and without the Coulomb interaction, which is the sole source of isospin symmetry breaking in our approach. The extended axial HFBTHO solver has been benchmarked against the symmetry-unrestricted HFODD code for deformed and spherical states. We developed and tested a general isospin-invariant Skyrme-EDF framework. The new approach permits spin-isospin densities that may give rise to, hitherto, unexplored modes in the excitation spectrum. The new formalism has been tested in the Hartree-Fock limit. A systematic comparison between HFODD and HFBTHO results show a maximum deviation of about 10 keV on the total binding energy for deformed nuclei when the Coulomb term is included. Without this term, the results of both solvers agree down to a ~10 eV level.

  18. Current scaling of axially radiated power in dynamic hohlraums and dynamic hohlraum load design for ZR.

    SciTech Connect (OSTI)

    Mock, Raymond Cecil; Nash, Thomas J.; Sanford, Thomas W. L.

    2007-03-01T23:59:59.000Z

    We present designs for dynamic hohlraum z-pinch loads on the 28 MA, 140 ns driver ZR. The scaling of axially radiated power with current in dynamic hohlraums is reviewed. With adequate stability on ZR this scaling indicates that 30 TW of axially radiated power should be possible. The performance of the dynamic hohlraum load on the 20 MA, 100 ns driver Z is extensively reviewed. The baseline z-pinch load on Z is a nested tungsten wire array imploding onto on-axis foam. Data from a variety of x-ray diagnostics fielded on Z are presented. These diagnostics include x-ray diodes, bolometers, fast x-ray imaging cameras, and crystal spectrometers. Analysis of these data indicates that the peak dynamic radiation temperature on Z is between 250 and 300 eV from a diameter less than 1 mm. Radiation from the dynamic hohlraum itself or from a radiatively driven pellet within the dynamic hohlraum has been used to probe a variety of matter associated with the dynamic hohlraum: the tungsten z-pinch itself, tungsten sliding across the end-on apertures, a titanium foil over the end aperture, and a silicon aerogel end cap. Data showing the existence of asymmetry in radiation emanating from the two ends of the dynamic hohlraum is presented, along with data showing load configurations that mitigate this asymmetry. 1D simulations of the dynamic hohlraum implosion are presented and compared to experimental data. The simulations provide insight into the dynamic hohlraum behavior but are not necessarily a reliable design tool because of the inherently 3D behavior of the imploding nested tungsten wire arrays.

  19. Wide-field functional imaging of blood flow and hemoglobin oxygen saturation in the rodent dorsal window chamber.

    E-Print Network [OSTI]

    2011-01-01T23:59:59.000Z

    et al. , editors. Anesthesia and Analgesia in LaboratoryPlace the animal in a gas anesthesia chamber filled with 5%much longer than with gas anesthesia. Conversely, using gas

  20. Dependence with air density of the response of the PTW SourceCheck ionization chamber for low energy brachytherapy sources

    SciTech Connect (OSTI)

    Tornero-López, Ana M.; Guirado, Damián; Ruiz-Arrebola, Samuel [Servicio de Radiofísica y Protección Radiológica, Hospital Universitario San Cecilio, E-18012 Granada (Spain)] [Servicio de Radiofísica y Protección Radiológica, Hospital Universitario San Cecilio, E-18012 Granada (Spain); Perez-Calatayud, Jose [Servicio de Radioterapia, Unidad de Radiofísica, Hospital Universitario y Politécnico La Fe, E-46026 Valencia (Spain)] [Servicio de Radioterapia, Unidad de Radiofísica, Hospital Universitario y Politécnico La Fe, E-46026 Valencia (Spain); Simancas, Fernando; Lallena, Antonio M. [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain)] [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain); Gazdic-Santic, Maja [Department of Medical Physics and Radiation Safety, Clinical Centre of Sarajevo University, 71000 Sarajevo (Bosnia and Herzegovina)] [Department of Medical Physics and Radiation Safety, Clinical Centre of Sarajevo University, 71000 Sarajevo (Bosnia and Herzegovina)

    2013-12-15T23:59:59.000Z

    Purpose: Air-communicating well ionization chambers are commonly used to assess air kerma strength of sources used in brachytherapy. The signal produced is supposed to be proportional to the air density within the chamber and, therefore, a density-independent air kerma strength is obtained when the measurement is corrected to standard atmospheric conditions using the usual temperature and pressure correction factor. Nevertheless, when assessing low energy sources, the ionization chambers may not fulfill that condition and a residual density dependence still remains after correction. In this work, the authors examined the behavior of the PTW 34051 SourceCheck ionization chamber when measuring the air kerma strength of {sup 125}I seeds.Methods: Four different SourceCheck chambers were analyzed. With each one of them, two series of measurements of the air kerma strength for {sup 125}I selectSeed{sup TM} brachytherapy sources were performed inside a pressure chamber and varying the pressure in a range from 747 to 1040 hPa (560 to 780 mm Hg). The temperature and relative humidity were kept basically constant. An analogous experiment was performed by taking measurements at different altitudes above sea level.Results: Contrary to other well-known ionization chambers, like the HDR1000 PLUS, in which the temperature-pressure correction factor overcorrects the measurements, in the SourceCheck ionization chamber they are undercorrected. At a typical atmospheric situation of 933 hPa (700 mm Hg) and 20 °C, this undercorrection turns out to be 1.5%. Corrected measurements show a residual linear dependence on the density and, as a consequence, an additional density dependent correction must be applied. The slope of this residual linear density dependence is different for each SourceCheck chamber investigated. The results obtained by taking measurements at different altitudes are compatible with those obtained with the pressure chamber.Conclusions: Variations of the altitude and changes in the weather conditions may produce significant density corrections, and that effect should be taken into account. This effect is chamber-dependent, indicating that a specific calibration is necessary for each particular chamber. To our knowledge, this correction has not been considered so far for SourceCheck ionization chambers, but its magnitude cannot be neglected in clinical practice. The atmospheric pressure and temperature at which the chamber was calibrated need to be taken into account, and they should be reported in the calibration certificate. In addition, each institution should analyze the particular response of its SourceCheck ionization chamber and compute the adequate correction factors. In the absence of a suitable pressure chamber, a possibility for this assessment is to take measurements at different altitudes, spanning a wide enough air density range.

  1. Supplemental Material for Severson et al. The axial element protein HTP-3 promotes cohesin loading and meiotic axis

    E-Print Network [OSTI]

    Meyer, Barbara

    Supplemental Material for Severson et al. The axial element protein HTP-3 promotes cohesin loading ......................................................................................... 7 Disrupting REC-8, HTP-3, or HTP-1/2 function reduces the lethality of spo-11(me44) mutants ....................................................................................... 13 The htp-3 deletion allele tm3655 phenocopies htp-3(y428). Supplemental Figure 8

  2. Path-integral solution for a two-dimensional model with axial-vector-current--pseudoscalar derivative interaction

    SciTech Connect (OSTI)

    Botelho, L.C.L.

    1985-03-15T23:59:59.000Z

    We study a two-dimensional quantum field model with axial-vector-current--pseudoscalar derivative interaction using path-integral methods. We construct an effective Lagrangian by performing a chiral change in the fermionic variables leading to an exact solution of the model.

  3. The effect of axial strain cycling on the critical current density and n-value of ITER niobium-tin

    E-Print Network [OSTI]

    Hampshire, Damian

    The effect of axial strain cycling on the critical current density and n-value of ITER niobium niobium-tin VAC and EM-LMI strands and the detailed characterisation of the EM-LMI-TFMC strand at -0 current density and n-value of two ITER candidate niobium-tin strands (EM- LMI and VAC). The strands were

  4. Identification of spin wave modes in yttrium iron garnet strongly coupled to a co-axial cavity.

    E-Print Network [OSTI]

    Lambert, N. J.; Haigh, J. A.; Ferguson, A. J.

    2015-02-05T23:59:59.000Z

    AIP/123-QED Identification of spin wave modes in yttrium iron garnet strongly coupled to a co-axial cavity. N. J. Lambert,1 J. A. Haigh,2 and A. J. Ferguson1 1)Microelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE...

  5. Validation of the Read Out Electronics for the CMS Muon Drift Chambers at Tests Beam in CERN/GIF

    E-Print Network [OSTI]

    Fernández, C; Fouz-Iglesias, M C; Marin, J; Oller, J C; Willmott, C

    2002-01-01T23:59:59.000Z

    Part of the readout system for the CMS muon drift chambers has been tested in test beams at CERN/GIF. Read Out Board (ROB) and HPTD have been validated with signals from a real muon beam, with an structure and flux similar to LHC operating conditions and using one of the chambers produced in CIEMAT already located in the test beam area under normal gas and voltage conditions. (Author) 5 refs.

  6. Measurement of changes in linear accelerator photon energy through flatness variation using an ion chamber array

    SciTech Connect (OSTI)

    Gao Song; Balter, Peter A. [Department of Radiation Physics, Unit 94, University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Rose, Mark; Simon, William E. [Sun Nuclear Corporation, 425-A Pineda Court, Melbourne, Florida 32940 (United States)

    2013-04-15T23:59:59.000Z

    Purpose: To compare the use of flatness versus percent depth dose (PDD) for determining changes in photon beam energy for a megavoltage linear accelerator. Methods: Energy changes were accomplished by adjusting the bending magnet current by up to {+-}15% in 5% increments away from the value used clinically. Two metrics for flatness, relative flatness in the central 80% of the field (Flat) and average maximum dose along the diagonals normalized by central axis dose (F{sub DN}), were measured using a commercially available planner ionization chamber array. PDD was measured in water at depths of 5 and 10 cm in 3 Multiplication-Sign 3 cm{sup 2} and 10 Multiplication-Sign 10 cm{sup 2} fields using a cylindrical chamber. Results: PDD was more sensitive to changes in energy when the beam energy was increased than when it was decreased. For the 18-MV beam in particular, PDD was not sensitive to energy reductions below the nominal energy. The value of Flat was found to be more sensitive to decreases in energy than to increases, with little sensitivity to energy increases above the nominal energy for 18-MV beams. F{sub DN} was the only metric that was found to be sensitive to both increases and reductions of energy for both the 6- and 18-MV beams. Conclusions: Flatness based metrics were found to be more sensitive to energy changes than PDD, In particular, F{sub DN} was found to be the most sensitive metric to energy changes for photon beams of 6 and 18 MV. The ionization chamber array allows this metric to be conveniently measured as part of routine accelerator quality assurance.

  7. High-Rate Glass Resistive Plate Chambers For LHC Muon Detectors Upgrade

    E-Print Network [OSTI]

    Laktineh, I; Cauwenbergh, S; Combret, C; Crotty, I; Haddad, Y; Grenier, G; Guida, R; Kieffer, R; Lumb, N; Mirabito, L; Schirra, F; Seguin, N; Tytgat, M; Van der Donckt, M; Wang, Y; Zaganidis, N

    2012-01-01T23:59:59.000Z

    The limitation of the detection rate of standard bakelite resistive plate chambers (RPC) used as muon detector in LHC experiments is behind the absence of such detectors in the high TJ regions in both CMS and ATLAS detectors. RPCs made with low resistivity glass plates (10ID O.cm) could be an adequate solution to equip the high TJ regions extending thus both the trigger efficiency and the physics performance. Different beam tests with single and multi-gap configurations using the new glass have shown that such detectors can operate at few thousands Hzlcm2 with high efficiency( > 90%).

  8. Low-NO{sub x} combustion chamber for a power generation gas-turbine unit

    SciTech Connect (OSTI)

    Gutnik, M.N.; Tumanovsky, A.G.; Soudarev, A.V.; Vinogradov, E.D.; Zakharov, Y.I.; Lobanov, D.V.; Akulov, V.A.

    1998-07-01T23:59:59.000Z

    The findings of the experimental studies over major operating characteristics of a full-scale combustion chamber (CC) for a new power generation 25 MW gas turbine unit of the AO ``Turbomotorny Zavod'' (Ekaterinburg) production are presented. A technique of the pre-mixed lean combustion with the excess air coefficient being approximately equal to 1.9--2.2 underlies the low NO{sub x} combustor design. Interrelations between the major combustor characteristics and design and duty parameters in parallel with the optimum algorithm of the combustor loading ensuring the minimum toxic exhausts into atmosphere are also shown in the paper.

  9. Development of time projection chamber for precise neutron lifetime measurement using pulsed cold neutron beams

    E-Print Network [OSTI]

    Arimoto, Y; Igarashi, Y; Iwashita, Y; Ino, T; Katayama, R; Kitahara, R; Kitaguchi, M; Matsumura, H; Mishima, K; Oide, H; Otono, H; Sakakibara, R; Shima, T; Shimizu, H M; Sugino, T; Sumi, N; Sumino, H; Taketani, K; Tanaka, G; Tanaka, M; Tauchi, K; Toyoda, A; Yamada, T; Yamashita, S; Yokoyama, H; Yoshioka, T

    2015-01-01T23:59:59.000Z

    A new time projection chamber (TPC) was developed for neutron lifetime measurement using a pulsed cold neutron spallation source at the Japan Proton Accelerator Research Complex (J-PARC). Managing considerable background events from natural sources and the beam radioactivity is a challenging aspect of this measurement. To overcome this problem, the developed TPC has unprecedented features such as the use of polyether-ether-ketone plates in the support structure and internal surfaces covered with $^6$Li-enriched tiles to absorb outlier neutrons. In this paper, the design and performance of the new TPC are reported in detail.

  10. Direct measurement of the impulse in a magnetic thrust chamber system for laser fusion rocket

    SciTech Connect (OSTI)

    Maeno, Akihiro; Yamamoto, Naoji; Nakashima, Hideki [Interdisciplinary Graduate School of Engineering Science, Kyushu University, 6-1 Kasuga-kouen, Kasuga, Fukuoka 816-8580 (Japan); Fujioka, Shinsuke; Johzaki, Tomoyuki [Institute of Laser Engineering, Osaka University, Suita, Osaka 565-087 (Japan); Mori, Yoshitaka [Graduate School for the Creation of New Photonics Industries, Hamamatsu, Shizuoka 431-1202 (Japan); Sunahara, Atsushi [Institute for Laser Technology, Suita, Osaka 565-087 (Japan)

    2011-08-15T23:59:59.000Z

    An experiment is conducted to measure an impulse for demonstrating a magnetic thrust chamber system for laser fusion rocket. The impulse is produced by the interaction between plasma and magnetic field. In the experiment, the system consists of plasma and neodymium permanent magnets. The plasma is created by a single-beam laser aiming at a polystyrene spherical target. The impulse is 1.5 to 2.2 {mu}Ns by means of a pendulum thrust stand, when the laser energy is 0.7 J. Without magnetic field, the measured impulse is found to be zero. These results indicate that the system for generating impulse is working.

  11. Development of time projection chamber for precise neutron lifetime measurement using pulsed cold neutron beams

    E-Print Network [OSTI]

    Y. Arimoto; N. Higashi; Y. Igarashi; Y. Iwashita; T. Ino; R. Katayama; R. Kitahara; M. Kitaguchi; H. Matsumura; K. Mishima; H. Oide; H. Otono; R. Sakakibara; T. Shima; H. M. Shimizu; T. Sugino; N. Sumi; H. Sumino; K. Taketani; G. Tanaka; M. Tanaka; K. Tauchi; A. Toyoda; T. Yamada; S. Yamashita; H. Yokoyama; T. Yoshioka

    2015-03-27T23:59:59.000Z

    A new time projection chamber (TPC) was developed for neutron lifetime measurement using a pulsed cold neutron spallation source at the Japan Proton Accelerator Research Complex (J-PARC). Managing considerable background events from natural sources and the beam radioactivity is a challenging aspect of this measurement. To overcome this problem, the developed TPC has unprecedented features such as the use of polyether-ether-ketone plates in the support structure and internal surfaces covered with $^6$Li-enriched tiles to absorb outlier neutrons. In this paper, the design and performance of the new TPC are reported in detail.

  12. Effects of discharge chamber length on the negative ion generation in volume-produced negative hydrogen ion source

    SciTech Connect (OSTI)

    Chung, Kyoung-Jae [Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)] [Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Jung, Bong-Ki; An, YoungHwa; Dang, Jeong-Jeung [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)] [Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Hwang, Y. S., E-mail: yhwang@snu.ac.kr [Center for Advance Research in Fusion Reactor Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of); Department of Nuclear Engineering, Seoul National University, Seoul 151-744 (Korea, Republic of)

    2014-02-15T23:59:59.000Z

    In a volume-produced negative hydrogen ion source, control of electron temperature is essential due to its close correlation with the generation of highly vibrationally excited hydrogen molecules in the heating region as well as the generation of negative hydrogen ions by dissociative attachment in the extraction region. In this study, geometric effects of the cylindrical discharge chamber on negative ion generation via electron temperature changes are investigated in two discharge chambers with different lengths of 7.5 cm and 11 cm. Measurements with a radio-frequency-compensated Langmuir probe show that the electron temperature in the heating region is significantly increased by reducing the length of the discharge chamber due to the reduced effective plasma size. A particle balance model which is modified to consider the effects of discharge chamber configuration on the plasma parameters explains the variation of the electron temperature with the chamber geometry and gas pressure quite well. Accordingly, H{sup ?} ion density measurement with laser photo-detachment in the short chamber shows a few times increase compared to the longer one at the same heating power depending on gas pressure. However, the increase drops significantly as operating gas pressure decreases, indicating increased electron temperatures in the extraction region degrade dissociative attachment significantly especially in the low pressure regime. It is concluded that the increase of electron temperature by adjusting the discharge chamber geometry is efficient to increase H{sup ?} ion production as long as low electron temperatures are maintained in the extraction region in volume-produced negative hydrogen ion sources.

  13. JOURNAL DE PHYSIQUE CoZZoque C3, suppZe'ment au no 12, Tome 43, ddcembre 1982 page C3-134

    E-Print Network [OSTI]

    Boyer, Edmond

    . They sat outside an axial superconducting solenoid magnet which contained a set of drift chambers used

  14. Strain and stability of ultrathin Ge layers in Si/Ge/Si axial heterojunction nanowires

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ross, Frances M.; Stach, Eric A.; Wen, Cheng -Yen; Reuter, Mark C.; Su, Dong

    2015-03-11T23:59:59.000Z

    The abrupt heterointerfaces in the Si/Ge materials system presents useful possibilities for electronic device engineering because the band structure can be affected by strain induced by the lattice mismatch. In planar layers, heterointerfaces with abrupt composition changes are difficult to realize without introducing misfit dislocations. However, in catalytically grown nanowires, abrupt heterointerfaces can be fabricated by appropriate choice of the catalyst. Here we grow nanowires containing Si/Ge and Si/Ge/Si structures respectively with sub-1nm thick Ge "quantum wells" and we measure the interfacial strain fields using geometric phase analysis. Narrow Ge layers show radial strains of several percent, with a correspondingmore »dilation in the axial direction. Si/Ge interfaces show lattice rotation and curvature of the lattice planes. We conclude that high strains can be achieved, compared to what is possible in planar layers. In addition, we study the stability of these heterostructures under heating and electron beam irradiation. The strain and composition gradients are supposed to the cause of the instability for interdiffusion.« less

  15. Creep Testing Plastic-Bonded Explosives in Uni-axial Compression

    SciTech Connect (OSTI)

    Gagliardi, F J; Cunningham, B J

    2008-03-13T23:59:59.000Z

    High fidelity measurements of time-dependent strain in the plastic-bonded explosives LX-17-1 and PBX 9502 have been performed under constant, uni-axial, compressive load using a custom designed apparatus. The apparatus uses a combination of extensometers and linear variable differential transformers coupled with a data acquisition system, thermal controls, and gravitational loading. The materials being tested consist of a crystalline explosive material mixed with a polymeric binder. The behavior of each material is related to the type of explosive and to the percentage and type of binder. For any given plastic-bonded explosive, the creep behavior is also dependent on the stress level and test temperature. Experiments were conducted using a 3 x 3 stress-temperature matrix with a temperature range of 24 C to 70 C and with stresses ranging from 250-psi to 780-psi. Analysis of the data has shown that logarithmic curve fits provide an accurate means of quantification and facilitate a long-term predictive capability. This paper will discuss the design of the apparatus, experimental results, and analyses.

  16. Ultra-high speed permanent magnet axial gap alternator with multiple stators

    DOE Patents [OSTI]

    Hawsey, Robert A. (Oak Ridge, TN); Bailey, J. Milton (Knoxville, TN)

    1991-01-01T23:59:59.000Z

    An ultra-high speed, axial gap alternator that can provide an output to a plurality of loads, the alternator providing magnetic isolation such that operating conditions in one load will not affect operating conditions of another load. This improved alternator uses a rotor member disposed between a pair of stator members, with magnets disposed in each of the rotor member surfaces facing the stator members. The magnets in one surface of the rotor member, which alternate in polarity, are isolated from the magnets in the other surface of the rotor member by a disk of magnetic material disposed between the two sets of magents. In the preferred embodiment, this disk of magnetic material is laminated between two layers of non-magnetic material that support the magnets, and the magnetic material has a peripheral rim that extends to both surfaces of the rotor member to enhance the structural integrity. The stator members are substantially conventional in construction in that equally-spaced and radially-oriented slots are provided, and winding members are laid in these slots. A unit with multiple rotor members and stator members is also described.

  17. Octupole deformation in light actinides within an analytic quadrupole octupole axially symmetric model with Davidson potential

    E-Print Network [OSTI]

    Bonatsos, Dennis; Minkov, N; Karampagia, S; Petrellis, D

    2015-01-01T23:59:59.000Z

    The analytic quadrupole octupole axially symmetric model, which had successfully predicted 226Ra and 226Th as lying at the border between the regions of octupole deformation and octupole vibrations in the light actinides using an infinite well potential (AQOA-IW), is made applicable to a wider region of nuclei exhibiting octupole deformation, through the use of a Davidson potential (AQOA-D). Analytic expressions for energy spectra and B(E1), B(E2), B(E3) transition rates are derived. The spectra of 222-226Ra and 224,226Th are described in terms of the two parameters phi_0 (expressing the relative amount of octupole vs. quadrupole deformation) and beta_0 (the position of the minimum of the Davidson potential), while the recently determined B(EL) transition rates of 224Ra, presenting stable octupole deformation, are successfully reproduced. A procedure for gradually determining the parameters appearing in the B(EL) transitions from a minimum set of data, thus increasing the predictive power of the model, is out...

  18. SU-D-19A-01: Can Farmer-Type Ionization Chambers Be Used to Improve the Accuracy of Low-Energy Electron Beam Reference Dosimetry?

    SciTech Connect (OSTI)

    Muir, B R; McEwen, M R [Measurement Science and Standards, National Research Council, Ottawa, ON (Canada)

    2014-06-01T23:59:59.000Z

    Purpose: To investigate the use of cylindrical Farmer-type ionization chambers to improve the accuracy of low-energy electron beam calibration. Historically, these chamber types have not been used in beams with incident energies less than 10 MeV (R{sub 5} {sub 0} < 4.3 cm) because early investigations suggested large (up to 5 %) fluence perturbation factors in these beams, implying that a significant component of uncertainty would be introduced if used for calibration. More recently, the assumptions used to determine perturbation corrections for cylindrical chambers have been questioned. Methods: Measurements are made with cylindrical chambers in Elekta Precise 4, 8 and 18 MeV electron beams. Several chamber types are investigated that employ graphite walls and aluminum electrodes with very similar specifications (NE2571, NE2505/3, FC65-G). Depth-ionization scans are measured in water in the 8 and 18 MeV beams. To reduce uncertainty from chamber positioning, measurements in the 4 MeV beam are made at the reference depth in Virtual Water™. The variability of perturbation factors is quantified by comparing normalized response of various chambers. Results: Normalized ion chamber response varies by less than 0.7 % for similar chambers at average electron energies corresponding to that at the reference depth from 4 or 6 MeV beams. Similarly, normalized measurements made with similar chambers at the reference depth in the 4 MeV beam vary by less than 0.4 %. Absorbed dose calibration coefficients derived from these results are stable within 0.1 % on average over a period of 6 years. Conclusion: These results indicate that the uncertainty associated with differences in fluence perturbations for cylindrical chambers with similar specifications is only 0.2 %. The excellent long-term stability of these chambers in both photon and electron beams suggests that these chambers might offer the best performance for all reference dosimetry applications.

  19. Progress on an integrated multi-physics simulation predictive capability for plasma chamber nuclear components

    SciTech Connect (OSTI)

    A. Ying; M. Abdou; H. Zhang; R. Munipalli; M. Ulrickson; M. Sawan; B. Merrill

    2010-12-01T23:59:59.000Z

    Understanding the behavior of a plasma chamber component in the fusion environment requires a simulation technique that is capable of integrating multi-disciplinary computational codes while appropriately treating geometric heterogeneity and complexity. Such a tool should be able to interpret phenomena from mutually dependent scientific disciplines and predict performance with sufficient accuracy and consistency. Integrated multi-physics simulation predictive capability (ISPC) relies upon advanced numerical simulation techniques and is being applied to ITER first wall/shield and Test Blanket Module (TBM) designs. In this paper, progress in ISPC development is described through the presentation of a number of integrated simulations. The simulations cover key physical phenomena encountered in a fusion plasma chamber system, including tritium permeation, fluid dynamics, and structure mechanics. Interface engines were developed in order to pass field data, such as surface deformation or nuclear heating rate, from the structural analysis to the thermo-fluid MHD analysis code for magnetohydrodynamic (MHD) velocity profile assessments, or from the neutronics analysis to the thermo-fluid analysis for temperature calculations, respectively. Near-term effort toward further ISPC development is discussed.

  20. Photoelectron track length distributions measured in a negative ion time projection chamber

    E-Print Network [OSTI]

    Prieskorn, Z R; Kaaret, P E; Black, J K

    2014-01-01T23:59:59.000Z

    We report photoelectron track length distributions between 3 and 8 keV in gas mixtures of Ne+CO2+CH3NO2 (260:80:10 Torr) and CO2+CH3NO2 (197.5: 15 Torr). The measurements were made using a negative ion time projection chamber (NITPC) at the National Synchrotron Light Source (NSLS) at the Brookhaven National Laboratory (BNL). We report the first quantitative analysis of photoelectron track length distributions in a gas. The distribution of track lengths at a given energy is best fit by a lognormal distribution. A powerlaw distribution of the form, f(E)=a(E/Eo)n, is found to fit the relationship between mean track length and energy. We find n=1.29 +/- 0.07 for Ne+CO2+CH3NO2 and n=1.20 +/- 0.09 for CO2+CH3NO2. Understanding the distribution of photoelectron track lengths in proportional counter gases is important for optimizing the pixel size and the dimensions of the active region in electron-drift time projection chambers (TPCs) and NITPC X-ray polarimeters.