National Library of Energy BETA

Sample records for axial magma chamber

  1. Evolution of silicic magma chambers and their relationship to...

    Office of Scientific and Technical Information (OSTI)

    Conference: Evolution of silicic magma chambers and their relationship to basaltic volcanism Citation Details In-Document Search Title: Evolution of silicic magma chambers and ...

  2. P-SV conversions at a shallow boundary beneath Campi Flegrei caldera (Italy) - evidence for the magma chamber

    SciTech Connect (OSTI)

    Ferrucci, F.; Hirn, A.; De Natale, G.; Virieux, J.; Mirabile, L. Inst. de Physique du Globe, Paris Osservatorio Vesuviano, Naples CNRS, Inst. de Geodynamique, Valbonne Ist. Universitario Navale, Naples )

    1992-10-01

    Seismograms from an active seismic experiment carried out at Campi Flegrei caldera (near Naples, Italy), show a large-amplitude SV-polarized shear wave, following by less than 1.5-s P waves reflected at wide angle from a deep crustal interface. Early arriving SV-polarized waves, with the same delay to direct P waves, are also observed in seismograms from a regional 280 km-deep, magnitude 5.1 earthquake. Such short delays of S to P waves are consistent with a P-SV conversion on transmission occurring at a shallow boundary beneath the receivers. The large amplitude of the converted-SV phase, along with that the P waves are near vertical, requires a boundary separating a very low rigidity layer from the upper caldera fill. The converted phases are interpreted as a seismic marker of a magma chamber. The top of this magma chamber is located slightly deeper than the deepest earthquakes observed during the 1982-1984 unrest of Campi Flegrei. 8 refs.

  3. New structural limits on magma chamber locations at the Valley of Ten Thousand Smokes, Katmai National Park, Alaska

    SciTech Connect (OSTI)

    Wallmann, P.C.; Pollard, D.D. ); Hildreth, W. ); Eichelberger, J.C. )

    1990-12-01

    New structural data from the Novarupta basin, Katmai National Park, Alaska, site of the largest volcanic eruption of this century (1912), provide limits for the location of magma chambers associated with this eruption. To investigate the subsurface structure of the 1912 vents, and to support an interdisciplinary study of this young volcanic system, a project of geologic mapping of surficial and bedrock structures in the vent region of the 1912 eruption has been undertaken. Landslide scarps, arcuate grabens, a monoclinal fold, and truncated ridges circumscribe the Novarupta basin, marking the inferred outer rim of the vent. A set of radial fissures crosses the southern margin of the basin, striking {approximately}140{degree}, subparallel to the dominant bedrock joint set. These fissures and joints, along with the local plate-motion vector and the inferred regional stress orientation, are consistent with a feeder dike propagating from a reservoir beneath Trident volcano to the eruptive vent.

  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

    2004-01-01

    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. Flow chamber

    DOE Patents [OSTI]

    Morozov, Victor

    2011-01-18

    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.

  6. Target Chamber

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

    Who Partners with NIF? FAQs Visit Us home about how nif works beamline target chamber Target Chamber The "Grand Central Station" of the National Ignition Facility is the ...

  7. Co-axial, high energy gamma generator

    DOE Patents [OSTI]

    Reijonen, Jani Petteri; Gicquel, Frederic

    2011-08-16

    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.

  8. Magma energy for power generation

    SciTech Connect (OSTI)

    Dunn, J.C.

    1987-01-01

    Thermal energy contained in crustal magma bodies represents a large potential resource for the US and magma generated power could become a viable alternative in the future. Engineering feasibility of the magma energy concept is being investigated as part of the Department of Energy's Geothermal Program. This current project follows a seven-year Magma Energy Research Project where scientific feasibility of the concept was concluded.

  9. Cyclone reactor with internal separation and axial recirculation

    DOE Patents [OSTI]

    Becker, Frederick E.; Smolensky, Leo A.

    1989-01-01

    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.

  10. Exposure chamber

    DOE Patents [OSTI]

    Moss, Owen R.; Briant, James K.

    1983-01-01

    An exposure chamber includes an imperforate casing having a fluid inlet at the top and an outlet at the bottom. A single vertical series of imperforate trays is provided. Each tray is spaced on all sides from the chamber walls. Baffles adjacent some of the trays restrict and direct the flow to give partial flow back and forth across the chambers and downward flow past the lowermost pan adjacent a central plane of the chamber.

  11. Cyclone reactor with internal separation and axial recirculation

    DOE Patents [OSTI]

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

    1988-07-19

    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.

    1980-01-01

    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. Wire chamber

    DOE Patents [OSTI]

    Atac, Muzaffer

    1989-01-01

    A wire chamber or proportional counter device, such as Geiger-Mueller tube or drift chamber, improved with a gas mixture providing a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor.

  14. IONIZATION CHAMBER

    DOE Patents [OSTI]

    Redman, W.C.; Shonka, F.R.

    1958-02-18

    This patent describes a novel ionization chamber which is well suited to measuring the radioactivity of the various portions of a wire as the wire is moved at a uniform speed, in order to produce the neutron flux traverse pattern of a reactor in which the wire was previously exposed to neutron radiation. The ionization chamber of the present invention is characterized by the construction wherein the wire is passed through a tubular, straight electrode and radiation shielding material is disposed along the wire except at an intermediate, narrow area where the second electrode of the chamber is located.

  15. Ionization chamber

    DOE Patents [OSTI]

    Walenta, Albert H.

    1981-01-01

    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.

  16. Ionization chamber

    DOE Patents [OSTI]

    Walenta, A.H.

    An ionization chamber is described which 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 ionizes the gas.

  17. Axial flow rotary engine

    SciTech Connect (OSTI)

    Loran, W.; Robinson, M.A.

    1989-07-18

    This paper describes an internal combustion engine. It comprises: a housing having an intake port at one end thereof and an exhaust port at the other end thereof; a compression chamber in the housing near the one end; compressor means in the compression chamber; a compressor transfer port opening through the downstream outlet wall; an expansion chamber in the housing near the other end thereof to receive combusted gases; work means in the expansion chamber driven by expanding, combusted gases; means rotating the compressor outlet wall at the same rotational drive speed as the expander inlet wall; an expansion chamber inlet port opening extending through the upstream inlet wall; a cylindrical combustion chamber block rotatable in the housing intermediate the compression chamber and the expansion chamber; at least two combustion chambers in the block; means rotating the block at a reduced speed relative to the speed of rotation of the compressor outlet wall and the expander inlet wall; means for igniting the charge of compressed gas during the intermediate portion of each revolution of the combustion chamber block. The combustion chambers being substantially hemispherical; the speed of rotation of the compressor outlet wall is in the same ratio to the speed of rotation of the combustion chamber block as the number of combustion chambers in the block is to the number of combustion chambers less one.

  18. Chamber transport

    SciTech Connect (OSTI)

    OLSON,CRAIG L.

    2000-05-17

    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.

  19. Measuring axial pump thrust

    DOE Patents [OSTI]

    Suchoza, Bernard P.; Becse, Imre

    1988-01-01

    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.

  20. Measuring axial pump thrust

    DOE Patents [OSTI]

    Suchoza, B.P.; Becse, I.

    1988-11-08

    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.

  1. Axial static mixer

    DOE Patents [OSTI]

    Sandrock, H.E.

    1982-05-06

    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.

  2. Property:AxialMeasurement | Open Energy Information

    Open Energy Info (EERE)

    String Description MHK Axial Load Measurement Categories Used in FormTemplate MHKSensor & MHKInstrument Allows Values Strain (Axial);3-axis (Axial);2-axis (Axial);1-axis...

  3. Magma energy and geothermal permeability enhancement programs

    SciTech Connect (OSTI)

    Dunn, J.C.

    1985-01-01

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

  4. Recent progress in magma energy extraction

    SciTech Connect (OSTI)

    Ortega, A.; Dunn, J.C.; Chu, T.Y.; Wemple, R.P.; Hickox, C.E.

    1987-01-01

    Ongoing research in the area of Magma Energy Extraction is directed at developing a fundamental understanding of the establishment and long term operation of an open, direct-contact heat exchanger in a crustal magma body. The energy extraction rate has a direct influence on the economic viability of the concept. An open heat exchanger, in which fluid is circulated through the interconnecting fissures and fractures in the solidified region around drilling tubing, offers the promise of very high rates of heat transfer. This paper discusses recent research in five areas: (1) fundamental mechanisms of solidifying and thermally fracturing magma; (2) convective heat transfer in the internally fractured solidified magma; (3) convective flow in the molten magma and heat transfer from the magma to the cooled heat exchanger protruding into it; (4) numerical simulation of the overall energy extraction process; and (5) the thermodynamics of energy conversion in a magma power plant at the surface. The studies show that an open heat exchanger can be formed by solidifying magma around a cooled borehole and that the resulting mass will be extensively fractured by thermally-induced stresses. Numerical models indicate that high quality thermal energy can be delivered at the wellhead at nominal rates from 25 to 30 MW electric. It is shown that optimum well circulation rates can be found that depend on the heat transfer characteristics of the magma heat exchanger and the thermodynamic power conversion efficiencies of the surface plant.

  5. Multi-cylinder axial stratified charging studied

    SciTech Connect (OSTI)

    Not Available

    1982-05-01

    Charge stratification can be obtained inside a noncylindrical combustion chamber of a fuel injected multi-cylinder engine by properly timing the injection event, directing the fuel spray into the inlet port, and imparting swirl to the inlet charge. A production 1.8-liter engine modified to operate as an axially stratified-charge engine showed 50% improvement in combustion stability, 3.5% lower fuel consumption, five research octane number lower octane requirement, and increased tolerance to dilute mixtures when compared with an unmodified engine.

  6. Combustion chamber, especially for gas turbines

    SciTech Connect (OSTI)

    Meyer, F.

    1980-04-29

    A combustion chamber is disclosed that has an end-wall at the inlet side and an axial inlet opening, which is adjoined by an essentially cylindrical wall section provided with secondary air inlet openings; the end-wall thereby adjoins the inlet opening approximately hemispherically shaped with a sphere diameter which is larger than the diameter of the cylindrical wall section while the adjoining combustion chamber portion is again reduced to the adjacent cylindrical wall section by way of a combustion chamber wall substantially continuing the sphere shape; the fuel injection device is provided upstream of the inlet opening which injects fuel into the inlet opening, itself covered off by a deflection means.

  7. Process for forming hydrogen and other fuels utilizing magma

    DOE Patents [OSTI]

    Galt, John K.; Gerlach, Terrence M.; Modreski, Peter J.; Northrup, Jr., Clyde J. M.

    1978-01-01

    The disclosure relates to a method for extracting hydrogen from magma and water by injecting water from above the earth's surface into a pocket of magma and extracting hydrogen produced by the water-magma reaction from the vicinity of the magma.

  8. Two chamber reaction furnace

    DOE Patents [OSTI]

    Blaugher, R.D.

    1998-05-05

    A vertical two chamber reaction furnace is described. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 C and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

  9. Two chamber reaction furnace

    DOE Patents [OSTI]

    Blaugher, Richard D.

    1998-05-05

    A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

  10. Status of the Magma Energy Project

    SciTech Connect (OSTI)

    Dunn, J.C.

    1987-01-01

    The current magma energy project is assessing the engineering feasibility of extracting thermal energy directly from crustal magma bodies. The estimated size of the US resource (50,000 to 500,000 quads) suggests a considerable potential impact on future power generation. In a previous seven-year study, we concluded that there are no insurmountable barriers that would invalidate the magma energy concept. Several concepts for drilling, energy extraction, and materials survivability were successfully demonstrated in Kilauea Iki lava lake, Hawaii. The present program is addressing the engineering design problems associated with accessing magma bodies and extracting thermal energy for power generation. The normal stages for development of a geothermal resource are being investigated: exploration, drilling and completions, production, and surface power plant design. Current status of the engineering program and future plans are described. 20 refs., 12 figs.

  11. The Magma Energy Program | Open Energy Information

    Open Energy Info (EERE)

    Article: The Magma Energy Program Abstract Abstract unavailable. Authors T.Y. Chu, J.C. Dunn, John T. Finger, John B. Rundle and H.R. Westrich Published Journal Geothermal...

  12. Kathy Chambers | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Kathy Chambers About Us Kathy Chambers - Senior Science and Technical Information Specialist, OSTI Most Recent by Kathy Chambers A Shining Example of Dr. King's legacy January 9

  13. Wall rock-magma interactions in Etna, Italy, studied by U-Th disequilibrium and rare earth element systematics

    SciTech Connect (OSTI)

    Villemant, B. CNRS URA 196, Paris ); Michaud, V.; Metrich, N. )

    1993-03-01

    [sup 230]Th/[sup 238]U disequilibria have been studied in xenoliths and associated lavas of the 1892 and 1989 eruptions of Etna. Most xenoliths are out of secular equilibrium within 1 [sigma] errors and have lower [sup 230]Th/[sup 232]Th ratios than their host magmas. Siliceous and peraluminous xenoliths display large ranges of Th/U ratios for similar [sup 230]Th/[sup 232]Th values, which are interpreted in terms of Th isotopic rehomogenization. The siliceous xenoliths have also suffered thorium and uranium enrichments, which are best explained by chemical diffusion between xenolith melts and differentiated magmas. Estimates of thorium self-diffusivities and [sup 230]Th-[sup 238]U disequilibria give age constraints on these events corresponding to the last major volcanic event of Etna at 14 ka (formation of the elliptic crater caldera). These results suggest that magma storage in superficial and long-lived magma chambers favors the thorium isotopic homogenization of wall rocks by a thermal effect. Chemical diffusion of uranium and thorium and isotopic homogenization between siliceous melts of wall rocks and differentiated magmas may significantly modify the initial thorium isotopic compositions. Such contamination processes could explain the large variations of the [sup 230]Th/[sup 232]Th initial ratios of Etna magmas. 33 refs., 7 figs., 1 tab.

  14. Axial gap rotating electrical machine

    DOE Patents [OSTI]

    None

    2016-02-23

    Direct drive rotating electrical machines with axial air gaps are disclosed. In these machines, a rotor ring and stator ring define an axial air gap between them. Sets of gap-maintaining rolling supports bear between the rotor ring and the stator ring at their peripheries to maintain the axial air gap. Also disclosed are wind turbines using these generators, and structures and methods for mounting direct drive rotating electrical generators to the hubs of wind turbines. In particular, the rotor ring of the generator may be carried directly by the hub of a wind turbine to rotate relative to a shaft without being mounted directly to the shaft.

  15. Sleeve reaction chamber system

    SciTech Connect (OSTI)

    Northrup, M. Allen; Beeman, Barton V.; Benett, William J.; Hadley, Dean R.; Landre, Phoebe; Lehew, Stacy L.; Krulevitch, Peter A.

    2009-08-25

    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.

  16. Automated soil gas monitoring chamber

    DOE Patents [OSTI]

    Edwards, Nelson T.; Riggs, Jeffery S.

    2003-07-29

    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.

  17. Improved wire chamber

    DOE Patents [OSTI]

    Atac, M.

    1987-05-12

    An improved gas mixture for use with proportional counter devices, such as Geiger-Mueller tubes and drift chambers. The improved gas mixture provides a stable drift velocity while eliminating wire aging caused by prior art gas mixtures. The new gas mixture is comprised of equal parts argon and ethane gas and having approximately 0.25% isopropyl alcohol vapor. 2 figs.

  18. Redox systematics of martian magmas with implications for magnetite...

    Office of Scientific and Technical Information (OSTI)

    with implications for magnetite stability Citation Details In-Document Search Title: Redox systematics of martian magmas with implications for magnetite stability Authors: ...

  19. A Multidisciplinary Approach To Detect Active Pathways For Magma...

    Open Energy Info (EERE)

    Multidisciplinary Approach To Detect Active Pathways For Magma Migration And Eruption At Mt Etna (Sicily, Italy) Before The 2001 And 2002-2003 Eruptions Jump to: navigation, search...

  20. Multi-chamber deposition system

    DOE Patents [OSTI]

    Jacobson, Richard L.; Jeffrey, Frank R.; Westerberg, Roger K.

    1989-06-27

    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.

  1. Multi-chamber deposition system

    DOE Patents [OSTI]

    Jacobson, Richard L.; Jeffrey, Frank R.; Westerberg, Roger K.

    1989-10-17

    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.

  2. Three chamber negative ion source

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Ehlers, Kenneth W.; Hiskes, John R.

    1985-01-01

    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.

  3. Vertical two chamber reaction furnace

    DOE Patents [OSTI]

    Blaugher, R.D.

    1999-03-16

    A vertical two chamber reaction furnace is disclosed. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

  4. Vertical two chamber reaction furnace

    DOE Patents [OSTI]

    Blaugher, Richard D.

    1999-03-16

    A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

  5. Multi-anode ionization chamber

    DOE Patents [OSTI]

    Bolotnikov, Aleksey E.; Smith, Graham; Mahler, George J.; Vanier, Peter E.

    2010-12-28

    The present invention includes a high-energy detector having a cathode chamber, a support member, and anode segments. The cathode chamber extends along a longitudinal axis. The support member is fixed within the cathode chamber and extends from the first end of the cathode chamber to the second end of the cathode chamber. The anode segments are supported by the support member and are spaced along the longitudinal surface of the support member. The anode segments are configured to generate at least a first electrical signal in response to electrons impinging thereon.

  6. Ionization chamber dosimeter

    DOE Patents [OSTI]

    Renner, Tim R.; Nyman, Mark A.; Stradtner, Ronald

    1991-01-01

    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.

  7. Axial diagnostic package for Z

    SciTech Connect (OSTI)

    Nash, T.J.; Derzon, M.S.; Chandler, G.

    1998-06-01

    The authors have developed and fielded an axial diagnostic package for the 20 MA, 100 ns, z-pinch driver Z. The package is used to diagnose dynamic hohlraum experiments which require an axial line of sight. The heart of the package is a reentrant cone originally used to diagnose ion-beam-driven hohlraums on PBFA-H. It has one diagnostic line of sight at 0 degrees, 4 at 6 degrees, and 4 at 9 degrees. In addition it has a number of viewing, alignment, and vacuum feedthrough ports. The front of the package sits approximately 5 feet from the pinch. This allows much closer proximity to the pinch, with inherently better resolution and signal, than is presently possible in viewing the pinch from the side. Debris that is preferentially directed along the axis is mitigated by two apertures for each line of sight, and by fast valves and imaging pinholes or cross slits for each diagnostic. In the initial run with this package they fielded a time resolved pinhole camera, a five-channel pinhole-apertured x-ray diode array, a bolometer, a spatially resolved time-integrated crystal spectrometer, and a spatially and temporally resolved crystal spectrometer. They present data obtained from these diagnostics in the dynamic hohlraum research conducted on Z.

  8. PWR AXIAL BURNUP PROFILE ANALYSIS

    SciTech Connect (OSTI)

    J.M. Acaglione

    2003-09-17

    The purpose of this activity is to develop a representative ''limiting'' axial burnup profile for pressurized water reactors (PWRs), which would encompass the isotopic axial variations caused by different assembly irradiation histories, and produce conservative isotopics with respect to criticality. The effect that the low burnup regions near the ends of spent fuel have on system reactivity is termed the ''end-effect''. This calculation will quantify the end-effects associated with Pressurized Water Reactor (PWR) fuel assemblies emplaced in a hypothetical 21 PWR waste package. The scope of this calculation covers an initial enrichment range of 3.0 through 5.0 wt% U-235 and a burnup range of 10 through 50 GWd/MTU. This activity supports the validation of the process for ensuring conservative generation of spent fuel isotopics with respect to criticality safety applications, and the use of burnup credit for commercial spent nuclear fuel. The intended use of these results will be in the development of PWR waste package loading curves, and applications involving burnup credit. Limitations of this evaluation are that the limiting profiles are only confirmed for use with the B&W 15 x 15 fuel assembly design. However, this assembly design is considered bounding of all other typical commercial PWR fuel assembly designs. This calculation is subject to the Quality Assurance Requirements and Description (QARD) because this activity supports investigations of items or barriers on the Q-list (YMP 2001).

  9. 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.

    1991-01-08

    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.

  10. Magma Dynamics at Yucca Mountain, Nevada

    SciTech Connect (OSTI)

    D. Krier

    2005-08-29

    Small-volume basaltic volcanic activity at Yucca Mountain has been identified as one of the potential events that could lead to release of radioactive material from the U.S. Department of Energy (DOE) designated nuclear waste repository at Yucca Mountain. Release of material could occur indirectly as a result of magmatic dike intrusion into the repository (with no associated surface eruption) by changing groundwater flow paths, or as a result of an eruption (dike intrusion of the repository drifts, followed by surface eruption of contaminated ash) or volcanic ejection of material onto the Earth's surface and the redistribution of contaminated volcanic tephra. Either release method includes interaction between emplacement drifts and a magmatic dike or conduit, and natural (geologic) processes that might interrupt or halt igneous activity. This analysis provides summary information on two approaches to evaluate effects of disruption at the repository by basaltic igneous activity: (1) descriptions of the physical geometry of ascending basaltic dikes and their interaction with silicic host rocks similar in composition to the repository host rocks; and (2) a summary of calculations developed to quantify the response of emplacement drifts that have been flooded with magma and repressurized following blockage of an eruptive conduit. The purpose of these analyses is to explore the potential consequences that could occur during the full duration of an igneous event.

  11. Ion chamber based neutron detectors

    DOE Patents [OSTI]

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

    2014-12-16

    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.

  12. A high rate proportional chamber

    SciTech Connect (OSTI)

    Henderson, R.; Fraszer, W.; Openshaw, R.; Sheffer, G.; Salomon, M.; Dew, S.; Marans, J.; Wilson, P.

    1987-02-01

    Gas mixtures with high specific ionization allow the use of small interelectrode distances while still maintaining full efficiency. With the short electron drift distances the timing resolution is also improved. The authors have built and operated two 25 cm/sup 2/ chambers with small interelectrode distances. Also single wire detector cells have been built to test gas mixture lifetimes. Various admixtures of CF/sub 4/, DME, Isobutane, Ethane and Argon have been tested. Possible applications of such chambers are as beam profile monitors, position tagging of rare events and front end chambers in spectrometers.

  13. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, B.E.

    1997-09-02

    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.

  14. Axial interaction free-electron laser

    DOE Patents [OSTI]

    Carlsten, Bruce E.

    1997-01-01

    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.

  15. The multigap resistive plate chamber

    SciTech Connect (OSTI)

    Zeballos, E. Cerron; Crotty, I.; Hatzifotiadou, D.; Valverde, J. Lamas; Neupane, S.; Williams, M. C. S.; Zichichi, A.

    2015-02-03

    The paper describes the multigap resistive plate chamber (RPC). This is a variant of the wide gap RPC. However it has much improved time resolution, while keeping all the other advantages of the wide gap RPC design.

  16. Light diffusing fiber optic chamber

    DOE Patents [OSTI]

    Maitland, Duncan J.

    2002-01-01

    A light diffusion system for transmitting light to a target area. The light is transmitted in a direction from a proximal end to a distal end by an optical fiber. A diffusing chamber is operatively connected to the optical fiber for transmitting the light from the proximal end to the distal end and transmitting said light to said target area. A plug is operatively connected to the diffusing chamber for increasing the light that is transmitted to the target area.

  17. Flow Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E.; Lindberg, William R.; Burgess, Robert K.; LaBelle, James

    2000-02-22

    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.

  18. 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.

    2005-10-06

    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.

  19. Plasma chemistry in wire chambers

    SciTech Connect (OSTI)

    Wise, J.

    1990-05-01

    The phenomenology of wire chamber aging is discussed and fundamentals of proportional counters are presented. Free-radical polymerization and plasma polymerization are discussed. The chemistry of wire aging is reviewed. Similarities between wire chamber plasma (>1 atm dc-discharge) and low-pressure rf-discharge plasmas, which have been more widely studied, are suggested. Construction and use of a system to allow study of the plasma reactions occurring in wire chambers is reported. A proportional tube irradiated by an {sup 55}Fe source is used as a model wire chamber. Condensable species in the proportional tube effluent are concentrated in a cryotrap and analyzed by gas chromatography/mass spectrometry. Several different wire chamber gases (methane, argon/methane, ethane, argon/ethane, propane, argon/isobutane) are tested and their reaction products qualitatively identified. For all gases tested except those containing methane, use of hygroscopic filters to remove trace water and oxygen contaminants from the gas resulted in an increase in the average molecular weight of the products, consistent with results from low-pressure rf-discharge plasmas. It is suggested that because water and oxygen inhibit polymer growth in the gas phase that they may also reduce polymer deposition in proportional tubes and therefore retard wire aging processes. Mechanistic implications of the plasma reactions of hydrocarbons with oxygen are suggested. Unresolved issues in this work and proposals for further study are discussed.

  20. Numerical Simulation of Earth Pressure on Head Chamber of Shield Machine with FEM

    SciTech Connect (OSTI)

    Li Shouju; Kang Chengang [State Key Laboratory of structural analysis for industrial equipment, Dalian University of Technology, Dalian 116023 (China); Sun, Wei [School of Mechanical Engineering, Dalian University of Technology, Dalian 116023 (China); Shangguan Zichang [School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian 116023 (China); Institute of Civil Engineering, Dalian Fishery University, Dalian 116023 (China)

    2010-05-21

    Model parameters of conditioned soils in head chamber of shield machine are determined based on tree-axial compression tests in laboratory. The loads acting on tunneling face are estimated according to static earth pressure principle. Based on Duncan-Chang nonlinear elastic constitutive model, the earth pressures on head chamber of shield machine are simulated in different aperture ratio cases for rotating cutterhead of shield machine. Relationship between pressure transportation factor and aperture ratio of shield machine is proposed by using aggression analysis.

  1. Chiral corrections to hyperon axial form factors

    SciTech Connect (OSTI)

    Jiang Fujiun; Tiburzi, B. C.

    2008-05-01

    We study the complete set of flavor-changing hyperon axial-current matrix elements at small momentum transfer. Using partially quenched heavy baryon chiral perturbation theory, we derive the chiral and momentum behavior of the axial and induced pseudoscalar form factors. The meson pole contributions to the latter posses a striking signal for chiral physics. We argue that the study of hyperon axial matrix elements enables a systematic lattice investigation of the efficacy of three-flavor chiral expansions in the baryon sector. This can be achieved by considering chiral corrections to SU(3) symmetry predictions, and their partially quenched generalizations. In particular, despite the presence of eight unknown low-energy constants, we are able to make next-to-leading order symmetry breaking predictions for two linear combinations of axial charges.

  2. Allan Cormack, Computerized Axial Tomography (CAT), and Magnetic...

    Office of Scientific and Technical Information (OSTI)

    Allan M. Cormack, Computerized Axial Tomography (CAT) and Magnetic Resonance Imaging (MRI) Resources with Additional Information magnetic resonance imaging system Computed axial...

  3. Split Venturi, Axially-Rotated Valve

    DOE Patents [OSTI]

    Walrath, David E.; Lindberg, William R.; Burgess, Robert K.

    2000-08-29

    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.

  4. The Mark III vertex chamber

    SciTech Connect (OSTI)

    Adler, J.; Bolton, T.; Bunnell, K.; Cassell, R.; Cheu, E.; Freese, T.; Grab, C.; Mazaheri, G.; Mir, R.; Odian, A.

    1987-07-01

    The design and construction of the new Mark III vertex chamber is described. Initial tests with cosmic rays prove the ability of track reconstruction and yield triplet resolutions below 50 ..mu..m at 3 atm using argon/ethane (50:50). Also performed are studies using a prototype of a pressurized wire vertex chamber with 8 mm diameter straw geometry. Spatial resolution of 35mm was obtained using dimethyl ether (DME) at 1 atm and 30 ..mu..m using argon/ethane (50/50 mixture) at 4 atm. Preliminary studies indicate the DME to adversely affect such materials as aluminized Mylar and Delrin.

  5. Test chamber for alpha spectrometry

    DOE Patents [OSTI]

    Larsen, Robert P.

    1977-01-01

    Alpha emitters for low-level radiochemical analysis by measurement of alpha spectra are positioned precisely with respect to the location of a surface-barrier detector by means of a chamber having a removable threaded planchet holder. A pedestal on the planchet holder holds a specimen in fixed engagement close to the detector. Insertion of the planchet holder establishes an O-ring seal that permits the chamber to be pumped to a desired vacuum. The detector is protected against accidental contact and resulting damage.

  6. Optimization of residual heat removal pump axial thrust and axial bearing

    SciTech Connect (OSTI)

    Schubert, F.

    1996-12-01

    The residual heat removal (RHR) pumps of German 1300 megawatt pressurized-water reactor (PWR) power plants are of the single stage end suction type with volute casing or with diffuser and forged circular casing. Due to the service conditions the pumps have to cover the full capacity range as well as a big variation in suction static pressure. This results in a big difference in the axial thrust that has to be borne by the axial bearing. Because these pumps are designed to operate without auxiliary systems (things that do not exist can not fail), they are equipped with antifriction bearings and sump oil lubrication. To minimize the heat production within the bearing casing, a number of PWR plants have pumps with combined axial/radial bearings of the ball type. Due to the fact that the maximum axial thrust caused by static pressure and hydrodynamic forces on the impeller is too big to be borne by that type of axial bearing, the impellers were designed to produce a hydrodynamic axial force that counteracts the static axial force. Thus, the resulting axial thrust may change direction when the static pressure varies.

  7. Signatures of confinement in axial gauge QCD

    SciTech Connect (OSTI)

    Lenz, F.; Moniz, Ernest J.; Thies, M.

    1995-09-01

    A comparative dynamical study of axial gauge QED and QCD is presented. Elementary excitations associated with particular field configurations are investigated. Gluonic excitations analogous to linearly polarized photons are shown to acquire infinite energy. Suppression of this class of excitations in QCD results from quantization of the chromo-electric flux and is interpreted as a dual Meissner effect, i.e., as expulsion from the QCD vacuum of chromo-electric fields which are constant over significant distances. This interpretation is supported by a comparative evaluation of the interaction energy of static charges in the axial gauge representation of QED and QCD. {copyright} 1995 Academic Press, Inc.

  8. Single wire drift chamber design

    SciTech Connect (OSTI)

    Krider, J.

    1987-03-30

    This report summarizes the design and prototype tests of single wire drift chambers to be used in Fermilab test beam lines. The goal is to build simple, reliable detectors which require a minimum of electronics. Spatial resolution should match the 300 ..mu..m rms resolution of the 1 mm proportional chambers that they will replace. The detectors will be used in beams with particle rates up to 20 KHz. Single track efficiency should be at least 99%. The first application will be in the MT beamline, which has been designed for calibration of CDF detectors. A set of four x-y modules will be used to track and measure the momentum of beam particles.

  9. Light diffusing fiber optic chamber (Patent) | DOEPatents

    Office of Scientific and Technical Information (OSTI)

    Country of Publication: United States Language: English Subject: light; diffusing; fiber; optic; chamber; light; diffusion; transmitting; light; target; light; transmitted; ...

  10. Sandia National Laboratories: Mode Stirred Chamber

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

    Mode Stirred Chamber The Mode Stirred chamber is essentially a large microwave oven. It consists of a metal room that serves as a high-Q chamber and a metal paddle wheel to "stir" the chamber modes. Mixing the modes in this manner allows test objects, in a single orientation to be exposed to EM energy in many different angles of incidence and polarization. Electronic susceptibility tests can be performed, or test object electromagnetic transfer functions can be determined through

  11. Rapid-quench axially staged combustor

    DOE Patents [OSTI]

    Feitelberg, Alan S.; Schmidt, Mark Christopher; Goebel, Steven George

    1999-01-01

    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.

  12. NIF Target Chamber Dedicated | National Nuclear Security Administration |

    National Nuclear Security Administration (NNSA)

    (NNSA) NIF Target Chamber Dedicated NIF Target Chamber Dedicated Livermore, CA Secretary Richardson dedicates the National Ignition Facility target chamber at DOE's Lawrence Livermore National Laboratory

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

    DOE Patents [OSTI]

    Reichner, Philip; Dollard, Walter J.

    1991-01-01

    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).

  14. Description of Axial Detail for ROK Fuel

    SciTech Connect (OSTI)

    Trellue, Holly R; Galloway, Jack D

    2012-04-20

    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

  15. Piping inspection carriage having axially displaceable sensor

    DOE Patents [OSTI]

    Zollinger, William T.; Treanor, Richard C.

    1994-01-01

    A pipe inspection instrument carriage for use with a pipe crawler for performing internal inspections of piping surfaces. The carriage has a front leg assembly, a rear leg assembly and a central support connecting the two assemblies and for mounting an instrument arm having inspection instruments. The instrument arm has a y-arm mounted distally thereon for axially aligning the inspection instrumentation and a mounting block, a linear actuator and axial movement arm for extending the inspection instruments radially outward to operably position the inspection instruments on the piping interior. Also, the carriage has a rotation motor and gear assembly for rotating the central support and the front leg assembly with respect to the rear leg assembly so that the inspection instruments azimuthally scan the piping interior. The instrument carriage allows performance of all piping inspection operations with a minimum of moving parts, thus decreasing the likelihood of performance failure.

  16. Piping inspection carriage having axially displaceable sensor

    DOE Patents [OSTI]

    Zollinger, W.T.; Treanor, R.C.

    1994-12-06

    A pipe inspection instrument carriage is described for use with a pipe crawler for performing internal inspections of piping surfaces. The carriage has a front leg assembly, a rear leg assembly and a central support connecting the two assemblies and for mounting an instrument arm having inspection instruments. The instrument arm has a Y-arm mounted distally thereon for axially aligning the inspection instrumentation and a mounting block, a linear actuator and axial movement arm for extending the inspection instruments radially outward to operably position the inspection instruments on the piping interior. Also, the carriage has a rotation motor and gear assembly for rotating the central support and the front leg assembly with respect to the rear leg assembly so that the inspection instruments azimuthally scan the piping interior. The instrument carriage allows performance of all piping inspection operations with a minimum of moving parts, thus decreasing the likelihood of performance failure. 4 figures.

  17. Chiral corrections and the axial charge of the delta

    SciTech Connect (OSTI)

    Jiang Fujiun; Tiburzi, Brian C.

    2008-07-01

    Chiral corrections to the delta axial charge are determined using heavy baryon chiral perturbation theory. Knowledge of this axial coupling is necessary to assess virtual-delta contributions to nucleon and delta observables. We give isospin relations useful for a lattice determination of the axial coupling. Furthermore, we detail partially quenched chiral corrections, which are relevant to address partial quenching and/or mixed action errors in lattice calculations of the delta axial charge.

  18. Isotopic evidence of source variations in commingled magma systems: Colorado River extensional corridor, Arizona and Nevada

    SciTech Connect (OSTI)

    Metcalf, R.V.; Smith, E.I.; Martin, M.W. . Dept. of Geoscience); Gonzales, D.A.; Walker, J.D. . Isotope Geochronology Lab.)

    1993-04-01

    Mixing of mantle derived mafic and crustal derived felsic magmas is a major Province-wide process forming Tertiary intermediate magmas within the Basin and Range. Major variations in magma sources, however, may exist in temporally and spatially related systems. Such variations are exemplified by two closely spaced plutons within the northern Colorado River extensional corridor. The 15.96 Ma Mt. Perkins pluton (MPP) was emplaced in three major phases: phase 1 (oldest) gabbro; phase 2 quartz diorite to hornblende granodiorite; and phase 3 biotite granodiorite ([+-]hbld). Phases 2 and 3 contain mafic microgranitoid enclaves (MME) that exhibit evidence of magma mingling. Combined data from phase 2 and 3 rocks, including MMW, shows positive [sup 87]Sr/[sup 86]Sr and negative [var epsilon]Nd correlations vs. SiO[sub 2] (50--72 wt %). Phase 2 rocks, which plot between phase 2 MME and MME-free phase 3 granodiorite, represent hybrid magmas formed by mixing of mantle and crustal derived magmas. Phase 1 gabbro falls off isotope-SiO[sub 2] trends and represents a separate mantle derived magma. The 13.2 Ma Wilson Ridge pluton (WRP), <20 km north of MPP, is cogenetic with the river Mountains volcano (RMV). In WRP an early diorite was intruded by a suite of monzodiorite to quartz monzonite. The monzodiorite portion contains MME and mafic schlieren representing mingled and mixed mafic magmas. The WRP and MPP represent two closely spaced isotopically distinct and separate magma systems. There are five magma sources. The two felsic mixing end members represent two different crustal magma sources. Two mantle sources are presented by MPP phase 1 gabbro and phase 2 MME, reflecting lithospheric and asthenospheric components, respectively. The latter represents the oldest reported Tertiary asthenospheric component within the region. A single lithospheric mantle source, different from the MPP gabbro, is indicated for the mafic mixing end member in the WRP-RMV suite.

  19. Georges Charpak, Particle Detectors, and Multiwire Chambers

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

    Georges Charpak, Particle Detectors, and Multiwire Chambers Resources with Additional Information * Patents Georges Charpak Courtesy of CERN Nobel laureate Georges Charpak [was] a pioneer in the art and science of particle detection ... . [He] developed a host of particle detectors used throughout experimental particle physics. In 1968, he invented and developed the first multiwire proportional chamber, for which he won the [Physics] Nobel Prize in 1992 ... . The multiwire chamber differed from

  20. Fluidized wall for protecting fusion chamber walls

    DOE Patents [OSTI]

    Maniscalco, James A.; Meier, Wayne R.

    1982-01-01

    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.

  1. Internal combustion engine with rotary combustion chamber

    SciTech Connect (OSTI)

    Hansen, C.N.; Cross, P.C.

    1986-09-23

    This patent describes an internal combustion engine comprising: a block having at least one cylindrical wall surrounding a piston chamber, piston means located in the piston chamber means operable to reciprocate the piston means in the chamber, head means mounted on the block covering the chamber. The head means has an air and fuel intake passage, and exhaust gas passage, a rotary valve assembly operatively associated with the head means for controlling the flow of air and fuel into the rotary valve assembly and piston chamber and the flow of exhaust gas from rotary valve assembly and the piston chamber. The means has a housing with a bore open to the piston chamber accommodating the rotary valve assembly, the valve assembly comprising a cylindrical sleeve located in the bore, the sleeve having an inner surface, an ignition hole, and intake and exhaust ports aligned with the intake passage and exhaust gas passage, spark generating means mounted on the housing operable to generate a spark. The rotatable valving means is located within the sleeve for controlling the flow of air and fuel into the rotary valve assembly and piston chamber and the flow of exhaust gases out of the rotary valve assembly and piston chamber.

  2. Axial flow heat exchanger devices and methods for heat transfer using axial flow devices

    DOE Patents [OSTI]

    Koplow, Jeffrey P.

    2016-02-16

    Systems and methods described herein are directed to rotary heat exchangers configured to transfer heat to a heat transfer medium flowing in substantially axial direction within the heat exchangers. Exemplary heat exchangers include a heat conducting structure which is configured to be in thermal contact with a thermal load or a thermal sink, and a heat transfer structure rotatably coupled to the heat conducting structure to form a gap region between the heat conducting structure and the heat transfer structure, the heat transfer structure being configured to rotate during operation of the device. In example devices heat may be transferred across the gap region from a heated axial flow of the heat transfer medium to a cool stationary heat conducting structure, or from a heated stationary conducting structure to a cool axial flow of the heat transfer medium.

  3. Axial Tomography from Digitized Real Time Radiography

    DOE R&D Accomplishments [OSTI]

    Zolnay, A. S.; McDonald, W. M.; Doupont, P. A.; McKinney, R. L.; Lee, M. M.

    1985-01-18

    Axial tomography from digitized real time radiographs provides a useful tool for industrial radiography and tomography. The components of this system are: x-ray source, image intensifier, video camera, video line extractor and digitizer, data storage and reconstruction computers. With this system it is possible to view a two dimensional x-ray image in real time at each angle of rotation and select the tomography plane of interest by choosing which video line to digitize. The digitization of a video line requires less than a second making data acquisition relatively short. Further improvements on this system are planned and initial results are reported.

  4. Compact ion chamber based neutron detector

    SciTech Connect (OSTI)

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

    2015-10-27

    A directional neutron detector has an ion chamber formed in a dielectric material; a signal electrode and a ground electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; readout circuitry which is electrically coupled to the signal and ground electrodes; and a signal processor electrically coupled to the readout circuitry. The ion chamber has a pair of substantially planar electrode surfaces. The chamber pressure of the neutron absorbing material is selected such that the reaction particle ion trail length for neutrons absorbed by the neutron absorbing material is equal to or less than the distance between the electrode surfaces. The signal processor is adapted to determine a path angle for each absorbed neutron based on the rise time of the corresponding pulse in a time-varying detector signal.

  5. Compact ion chamber based neutron detector

    SciTech Connect (OSTI)

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

    2015-11-05

    A directional neutron detector has an ion chamber formed in a dielectric material; a signal electrode and a ground electrode formed in the ion chamber; a neutron absorbing material filling the ion chamber; readout circuitry which is electrically coupled to the signal and ground electrodes; and a signal processor electrically coupled to the readout circuitry. The ion chamber has a pair of substantially planar electrode surfaces. The chamber pressure of the neutron absorbing material is selected such that the reaction particle ion trail length for neutrons absorbed by the neutron absorbing material is equal to or less than the distance between the electrode surfaces. The signal processor is adapted to determine a path angle for each absorbed neutron based on the rise time of the corresponding pulse in a time-varying detector signal.

  6. Ionization-chamber smoke detector system

    DOE Patents [OSTI]

    Roe, Robert F.

    1976-10-19

    This invention relates to an improved smoke-detection system of the ionization-chamber type. In the preferred embodiment, the system utilizes a conventional detector head comprising a measuring ionization chamber, a reference ionization chamber, and a normally non-conductive gas triode for discharging when a threshold concentration of airborne particulates is present in the measuring chamber. The improved system is designed to reduce false alarms caused by fluctuations in ambient temperature. Means are provided for periodically firing the gas discharge triode and each time recording the triggering voltage required. A computer compares each triggering voltage with its predecessor. The computer is programmed to energize an alarm if the difference between the two compared voltages is a relatively large value indicative of particulates in the measuring chamber and to disregard smaller differences typically resulting from changes in ambient temperature.

  7. RADIATION MONITOR CONTAINING TWO CONCENTRIC IONIZATION CHAMBERS AND MEANS FOR INSULATING THE SEPARATE CHAMBERS

    DOE Patents [OSTI]

    Braestrup, C.B.; Mooney, R.T.

    1964-01-21

    This invention relates to a portable radiation monitor containing two concentric ionization chambers which permit the use of standard charging and reading devices. It is particularly adapted as a personnel x-ray dosimeter and to this end comprises a small thin walled, cylindrical conductor forming an inner energy dependent chamber, a small thin walled, cylindrical conductor forming an outer energy independent chamber, and polymeric insulation means which insulates said chambers from each other and holds the chambers together with exposed connections in a simple, trouble-free, and compact assembly substantially without variation in directional response. (AEC)

  8. Axial Burnup Profile Database for Pressurized Water Reactors.

    Energy Science and Technology Software Center (OSTI)

    2000-09-18

    Version: 00 The main objective of the database is to provide a detailed characterization of spent PWR fuel, specifically with respect to the axial burnup distribution.

  9. Nuclear axial currents in chiral effective field theory

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Baroni, Alessandro; Girlanda, Luca; Pastore, Saori; Schiavilla, Rocco; Viviani, Michele

    2016-01-11

    Two-nucleon axial charge and current operators are derived in chiral effective field theory up to one loop. The derivation is based on time-ordered perturbation theory and accounts for cancellations between the contributions of irreducible diagrams and the contributions owing to nonstatic corrections from energy denominators of reducible diagrams. Ultraviolet divergencies associated with the loop corrections are isolated in dimensional regularization. The resulting axial current is finite and conserved in the chiral limit, while the axial charge requires renormalization. As a result, a complete set of contact terms for the axial charge up to the relevant order in the power countingmore » is constructed.« less

  10. China New Energy Chamber of Commerce CNECC | Open Energy Information

    Open Energy Info (EERE)

    Chamber of Commerce CNECC Jump to: navigation, search Name: China New Energy Chamber of Commerce (CNECC) Place: Beijing, Beijing Municipality, China Zip: 100052 Product: A Chinese...

  11. Development of Microstrip Gas Chambers for Radiation Detection...

    Office of Scientific and Technical Information (OSTI)

    Gas Chambers for Radiation Detection and Tracking at High Rates: Final Status Repor Citation Details In-Document Search Title: Development of Microstrip Gas Chambers for ...

  12. History of the superconducting-magnet bubble chambers

    SciTech Connect (OSTI)

    Derrick, M.; Hyman, L.G.; Pewitt, E.G.

    1980-01-01

    This review covers the development of superconducting magnets, small bubble chambers, and the early history of the 12-foot bubble chamber. (MOW)

  13. Gas Electron Multiplier (GEM) Chamber Characteristics Test (Technical...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: Gas Electron Multiplier (GEM) Chamber Characteristics Test Citation Details In-Document Search Title: Gas Electron Multiplier (GEM) Chamber Characteristics Test ...

  14. ON THE ANALYSIS OF BUBBLE CHAMBER TRACKS Bradner, H.; Solmitz...

    Office of Scientific and Technical Information (OSTI)

    ON THE ANALYSIS OF BUBBLE CHAMBER TRACKS Bradner, H.; Solmitz, F. 08 HYDROGEN; 43 PARTICLE ACCELERATORS; BEVATRON; BUBBLE CHAMBERS; DETECTION; HYDROCARBONS; HYDROGEN; INVENTIONS;...

  15. Sealable femtoliter chamber arrays for cell-free biology (Journal...

    Office of Scientific and Technical Information (OSTI)

    Sealable femtoliter chamber arrays for cell-free biology Prev Next Title: Sealable femtoliter chamber arrays for cell-free biology You are accessing a document from the ...

  16. High Power Co-Axial Coupler

    SciTech Connect (OSTI)

    Johnson, Rolland; Neubauer, Michael

    2013-08-14

    A superconducting RF (SRF) power coupler capable of handling 500 kW CW RF power at 750 MHz is required for present and future storage rings and linacs. There are over 35 coupler designs for SRF cavities ranging in frequency from 325 to 1500 MHz. Coupler windows vary from cylinders to cones to disks and RF power couplers will always be limited by the ability of ceramic windows and their matching systems to withstand the stresses due to non-uniform heating from dielectric and wall losses, multipactor, and mechanical flexure. In the Phase II project, we built a double window coaxial system with materials that would not otherwise be useable due to individual VSWRs. Double window systems can be operated such that one is cold (LN2) and one is warm. They can have different materials and still have a good match without using matching elements that create problematic multipactor bands. The match of the two windows will always result from the cancellation of the two window’s reflections when they are located approximately a quarter wavelength apart or multiples of a quarter wavelength. The window assemblies were carefully constructed to put the window material and its braze joint in compression at all times. This was done using explosion bonding techniques which allow for inexpensive fabrication of the vacuum / compression ring out of stainless steel with copper plating applied to the inner surface. The EIA 3-1/8” double window assembly was then successfully baked out and tested to 12 kW in a 3-1/8” co-axial system. The thermal gradient across the window was measured to be 90 C which represents about 15 ksi tensile stress in an uncompressed window. In our design the compression was calculated to be about 25 ksi, so the net compressive force was 5 ksi at full power.

  17. Miniature reaction chamber and devices incorporating same

    DOE Patents [OSTI]

    Mathies, Richard A.; Woolley, Adam T.

    2000-10-17

    The present invention generally relates to miniaturized devices for carrying out and controlling chemical reactions and analyses. In particular, the present invention provides devices which have miniature temperature controlled reaction chambers for carrying out a variety of synthetic and diagnostic applications, such as PCR amplification, nucleic acid hybridization, chemical labeling, nucleic acid fragmentation and the like.

  18. Hyperon axial charges in two-flavor chiral perturbation theory

    SciTech Connect (OSTI)

    Jiang Fujiun; Tiburzi, Brian C.

    2009-10-01

    We use two-flavor heavy baryon chiral perturbation theory to investigate the isovector axial charges of the spin one-half hyperons. Expressions for these hyperon axial charges are derived at next-to-leading order in the chiral expansion. We utilize phenomenological and lattice QCD inputs to assess the convergence of the two-flavor theory, which appears to be best for cascades.

  19. Gas Injection Apparatus for Vacuum Chamber

    SciTech Connect (OSTI)

    Almabouada, F.; Louhibi, D.; Hamici, M.

    2011-12-26

    We present in this article a gas injection apparatus which comprises the gas injector and its electronic command for vacuum chamber applications. Some of these applications are thin-film deposition by a pulsed laser deposition (PLD) or a cathodic arc deposition (arc-PVD) and the plasma generation. The electronic part has been developed to adjust the flow of the gas inside the vacuum chamber by controlling both of the injector's opening time and the repetition frequency to allow a better gas flow. In this case, the system works either on a pulsed mode or a continuous mode for some applications. In addition, the repetition frequency can be synchronised with a pulsed laser by an external signal coming from the laser, which is considered as an advantage for users. Good results have been obtained using the apparatus and testing with Argon and Nitrogen gases.

  20. Combustion chamber for a gas turbine

    SciTech Connect (OSTI)

    Holzapfel, I.

    1982-09-21

    A combustion chamber for a gas turbine, in particular for motor vehicles, with an atomizer nozzle for the fuel fed to a prechamber, in which the inlet cross section for the primary air is changed by the longitudinal movement of a deflection member extending through the inlet opening of the combustion chamber. The deflection member serves as a flame holder for the stabilization of the combustion in the primary air zone while the air-atomizing nozzle is constructed ring-shaped and is provided with swirl slots in such a manner that the mixture of the fuel and of the atomizing air enters as an annular jet the primary air inlet channel, impinges approximately perpendicularly onto the primary air flow, penetrates the same and uniformly mixes with the same on its way to the inlet into the primary zone. The quantity of the primary air to be supplied is thereby automatically adjustable.

  1. OSTIblog Articles in the Tennessee Chamber of Commerce and Industry...

    Office of Scientific and Technical Information (OSTI)

    We are proud to note that OSTI was featured in the Tennessee Chamber of Commerce & Industry'ssummer issue of its newsletter, the Business Insider. The Chamber says that OSTI and ...

  2. Minority Chamber of Commerce "How to do Business with Federal...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Minority Chamber of Commerce "How to do Business with Federal Government" Minority Chamber of Commerce "How to do Business with Federal Government" October 29, 2015 9:00AM to...

  3. The American Chamber of Commerce of Trinidad & Tobago | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    The American Chamber of Commerce of Trinidad & Tobago The American Chamber of Commerce of Trinidad & Tobago May 13, 2008 - 12:00pm Addthis Remarks As Prepared for Delivery by...

  4. Automated soil gas monitoring chamber (Patent) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    Title: Automated soil gas monitoring chamber A chamber for trapping soil gases as they evolve from the soil without disturbance to the soil and to the natural microclimate within ...

  5. Focusing, in-chamber spectrometer triplet for high resolution measurements on the Sandia Z facility

    SciTech Connect (OSTI)

    Wenger, D. F.; Sinars, D. B.; Rochau, G. A.; Bailey, J. E.; Porter, J. L.; Faenov, A. Ya.; Pikuz, T. A.; Pikuz, S. A.

    2006-10-15

    An early prototype of a focusing spectrometer with one-dimensional (1D) spatial resolution (FSSR) instrument was previously developed for use in the vacuum chamber of the Sandia Z facility [Sinars et al., J. Quant. Spectrosc. Radiat. Transf. 99, 595 (2006)]. This instrument used a single, spherically bent crystal to measure time-integrated Ar spectra from 0.295-0.378 nm with {lambda}/{delta}{lambda}>2000 and a 1D axial spatial resolution of {approx}50 {mu}m. We present the design of a final version of this instrument that improves the shielding, can be aligned more accurately, and uses three crystals instead of one. The last change enables coverage of multiple spectral ranges if different crystals are used, or multiple times if identical crystals and time-gated detectors are used. We also present results from initial prototyping tests on the Z facility using two crystals in a time-integrated mode.

  6. Axially staggered seed-blanket reactor fuel module construction

    DOE Patents [OSTI]

    Cowell, Gary K.; DiGuiseppe, Carl P.

    1985-01-01

    A heterogeneous nuclear reactor of the seed-blanket type is provided wher 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. The arrangements of the fissile and fertile regions in an alternating axial manner minimizes the radial power peaking factors and provides a more optional thermal-hydraulic design than is afforded by radial arrangements.

  7. Allan Cormack, Computerized Axial Tomography (CAT), and Magnetic Resonance

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

    Imaging (MRI) Allan M. Cormack, Computerized Axial Tomography (CAT) and Magnetic Resonance Imaging (MRI) Resources with Additional Information magnetic resonance imaging system Computed axial tomography, commonly known as CAT scanning, was introduced in 1972. During a CAT scan, a large coil of x-ray tubes rotates around the patient's body, taking x-rays from all angles. A computer integrates all of these x-rays into a single, three-dimensional image on a television screen. The data can be

  8. Numerical study of nucleation and growth of bubbles in viscous magmas

    SciTech Connect (OSTI)

    Toramaru, A.

    1995-02-01

    The nucleation and growth processes of bubbles in viscous magmas with a constant decompression rate have been numerically investigated based on a formation which accounts for effects of viscosity, as well as diffusivity, interfacial tension, and decompression rate. The numerical solutions show two regimes in the nucleation and growth process, a diffusion-controlled regime and a viscosity-controlled regime, mainly depending on the decompression rate, initial saturation pressure and viscosity. The basic mechanism common to both regimes is that growth governs nucleation through depletion of degassing components. In basaltic eruptions the vesiculation is essentially controlled by diffusion, and the viscosity-controlled regime is limited to very high decompression rate and very small water content. When andesitic magma saturated by water at 10 MPa is decompressed through the propagation of rarefraction wave induced by a landslide, as took place in the Mount St. Helens 1980 eruption, the vesiculation is controlled by the viscosity up to 100 m depth. On the other hand, in a rhyolitic magma for the same situation, vesiculation is controlled by the viscosity over the whole depth of the magma column. In the viscosity-controlled regime, the vesicularity may be 90% or less as seen in silicic pumice, whereas in the diffusion-controlled regime the vesicularity equals or exceeds 98% such as in reticulite in Hawaiian basalt. An observed variation of the number density of bubbles by several orders of magnitude in plinian eruptions and the correlation with the SiO2 content can be attributed approximately to the dependence of diffusivity of viscosity on SiO2 content and temperature, assuming the apparent correlation between SiO2 content and temperature of magma.

  9. Vacuum chamber for containing particle beams

    DOE Patents [OSTI]

    Harvey, Alexander

    1987-01-01

    A vacuum chamber for containing a charged particle beam in a rapidly changing magnetic environment comprises a ceramic pipe with conducting strips oriented along the longitudinal axis of the pipe and with circumferential conducting bands oriented perpendicular to the longitudinal axis but joined with a single longitudinal electrical connection. When both strips and bands are on the outside of the ceramic pipe, insulated from each other, a high-resistance conductive layer, such as nickel can be coated on the inside of the pipe.

  10. Vacuum chamber for containing particle beams

    DOE Patents [OSTI]

    Harvey, A.

    1985-11-26

    A vacuum chamber for containing a charged particle beam in a rapidly changing magnetic environment comprises a ceramic pipe with conducting strips oriented along the longitudinal axis of the pipe and with circumferential conducting bands oriented perpendicular to the longitudinal axis but joined with a single longitudinal electrical connection. When both strips and bands are on the outside of the ceramic pipe, insulated from each other, a high-resistance conductive layer such as nickel can be coated on the inside of the pipe.

  11. Right/left assignment in drift chambers and proportional multiwire chambers (PWC's) using induced signals

    DOE Patents [OSTI]

    Walenta, Albert H.

    1979-01-01

    Improved multiwire chamber having means for resolving the left/right ambiguity in the location of an ionizing event. The chamber includes a plurality of spaced parallel anode wires positioned between spaced planar cathodes. Associated with each of the anode wires are a pair of localizing wires, one positioned on either side of the anode wire. The localizing wires are connected to a differential amplifier whose output polarity is determined by whether the ionizing event occurs to the right or left of the anode wire.

  12. Vacuum chamber with a supersonic flow aerodynamic window

    DOE Patents [OSTI]

    Hanson, Clark L.

    1982-01-01

    A supersonic flow aerodynamic window, whereby a steam ejector situated in a primary chamber at vacuum exhausts superheated steam toward an orifice to a region of higher pressure, creating a barrier to the gas in the region of higher pressure which attempts to enter through the orifice. In a mixing chamber outside and in fluid communication with the primary chamber, superheated steam and gas are combined into a mixture which then enters the primary chamber through the orifice. At the point of impact of the ejector/superheated steam and the incoming gas/superheated steam mixture, a barrier is created to the gas attempting to enter the ejector chamber. This barrier, coupled with suitable vacuum pumping means and cooling means, serves to keep the steam ejector and primary chamber at a negative pressure, even though the primary chamber has an orifice to a region of higher pressure.

  13. Vacuum chamber with a supersonic-flow aerodynamic window

    DOE Patents [OSTI]

    Hanson, C.L.

    1980-10-14

    A supersonic flow aerodynamic window is disclosed whereby a steam ejector situated in a primary chamber at vacuum exhausts superheated steam toward an orifice to a region of higher pressure, creating a barrier to the gas in the region of higher pressure which attempts to enter through the orifice. In a mixing chamber outside and in fluid communication with the primary chamber, superheated steam and gas are combined into a mixture which then enters the primary chamber through the orifice. At the point of impact of the ejector/superheated steam and the incoming gas/superheated steam mixture, a barrier is created to the gas attempting to enter the ejector chamber. This barrier, coupled with suitable vacuum pumping means and cooling means, serves to keep the steam ejector and primary chamber at a negative pressure, even though the primary chamber has an orifice to a region of higher pressure.

  14. Fission gas retention and axial expansion of irradiated metallic fuel

    SciTech Connect (OSTI)

    Fenske, G.R.; Emerson, J.E.; Savoie, F.E.; Johanson, E.W.

    1986-05-01

    Out-of-reactor experiments utilizing direct electrical heating and infrared heating techniques were performed on irradiated metallic fuel. The results indicate accelerated expansion can occur during thermal transients and that the accelerated expansion is driven by retained fission gases. The results also demonstrate gas retention and, hence, expansion behavior is a function of axial position within the pin.

  15. Hydrostatic self-aligning axial/torsional mechanism

    DOE Patents [OSTI]

    O'Connor, Daniel G. (Knoxville, TN); Gerth, Howard L. (Knoxville, TN)

    1990-01-01

    The present invention is directed to a self-aligning axial/torsional loading mechanism for testing the strength of brittle materials which are sensitive to bending moments. Disposed inside said self-aligning loading mechanism is a frictionless hydrostatic ball joint with a flexure ring to accommodate torsional loads through said ball joint.

  16. Wire chamber radiation detector with discharge control

    DOE Patents [OSTI]

    Perez-Mendez, Victor; Mulera, Terrence A.

    1984-01-01

    A wire chamber radiation detector (11) has spaced apart parallel electrodes (16) and grids (17, 18, 19) defining an ignition region (21) in which charged particles (12) or other ionizing radiations initiate brief localized avalanche discharges (93) and defining an adjacent memory region (22) in which sustained glow discharges (94) are initiated by the primary discharges (93). Conductors (29, 32) of the grids (18, 19) at each side of the memory section (22) extend in orthogonal directions enabling readout of the X-Y coordinates of locations at which charged particles (12) were detected by sequentially transmitting pulses to the conductors (29) of one grid (18) while detecting transmissions of the pulses to the orthogonal conductors (36) of the other grid (19) through glow discharges (94). One of the grids (19) bounding the memory region (22) is defined by an array of conductive elements (32) each of which is connected to the associated readout conductor (36) through a separate resistance (37). The wire chamber (11) avoids ambiguities and imprecisions in the readout of coordinates when large numbers of simultaneous or near simultaneous charged particles (12) have been detected. Down time between detection periods and the generation of radio frequency noise are also reduced.

  17. Quantum combustion chamber for the digital engine

    SciTech Connect (OSTI)

    Evers, L.W.; Baasch, V.

    1985-01-01

    For increasing fuel economy and reducing hydrocarbon emissions, a two-stoke-cycle, loop-scavenged single cylinder engine was modified by replacing the head with a head having three subchambers and incorporating a distributing pump fuel injection system. The fuel injection system allowed one subchamber to be operated at a time. The quantum combustion system demonstrated both lower fuel consumption and lower hydrocarbon emissions than a conventional homogeneous charge engine. The experimental evidence also indicates that the combustion essentially occurred in the one chamber into which fuel was injected. Establishing stratified charge combustion by mechanically separating the regions of air from the regions of air/fuel mixtures by means of subchambers is feasible.

  18. 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. )

    1988-04-01

    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.

  19. Jo Sexton, President, Cambridge Area Chamber of Commerce Panel...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Outliine for QER July 21, 2014 Jo Sexton, President, Cambridge Area Chamber of Commerce Panel 3 Public-Private Partnerships for Economic Growth and Workforce Development How a ...

  20. Saku Chamber of Commers Indsutry | Open Energy Information

    Open Energy Info (EERE)

    Jump to: navigation, search Name: Saku Chamber of Commers&Indsutry Place: Saku, Nagano, Japan Zip: 3850051 Product: An organization engages in improving the collaboration and...

  1. Donald Glaser, the Bubble Chamber, and Elementary Particles

    Office of Scientific and Technical Information (OSTI)

    Biotech Pioneer Donald Glaser ... Donald A. Glaser, Ph.D.; The Bubble Chamber, ... Neurobiology (an interview) -- accepting agreement results in receiving the document Invention...

  2. Chambers County, Alabama: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Chambers County, Alabama: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 32.9028048, -85.354965 Show Map Loading map... "minzoom":false,"mappi...

  3. Luis Alvarez, the Hydrogen Bubble Chamber, Tritium, and Dinosaurs

    Office of Scientific and Technical Information (OSTI)

    Luis Alvarez, the Hydrogen Bubble Chamber, Tritium, and Dinosaurs Resources with ... standard of length, co-discovered the hydrogen isotope tritium, searched for hidden ...

  4. Chambers County, Texas: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    County, Texas Reliant Baytown Biomass Facility Places in Chambers County, Texas Anahuac, Texas Baytown, Texas Beach City, Texas Cove, Texas Mont Belvieu, Texas Old...

  5. Chamber of Commerce Recognizes Portsmouth Site Specific Advisory Board

    Broader source: Energy.gov [DOE]

    PIKETON, Ohio – The Pike County Chamber of Commerce recently recognized the Portsmouth Site Specific Advisory Board (SSAB) as its 2015 Organization of the Year.

  6. Axially staged combustion system for a gas turbine engine

    DOE Patents [OSTI]

    Bland, Robert J.

    2009-12-15

    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.

  7. Axially Tapered And Bilayer Microchannels For Evaporative Cooling Devices

    DOE Patents [OSTI]

    Nilson, Robert; Griffiths, Stewart

    2005-10-04

    The invention consists of an evaporative cooling device comprising one or more microchannels whose cross section is axially reduced to control the maximum capillary pressure differential between liquid and vapor phases. In one embodiment, the evaporation channels have a rectangular cross section that is reduced in width along a flow path. In another embodiment, channels of fixed width are patterned with an array of microfabricated post-like features such that the feature size and spacing are gradually reduced along the flow path. Other embodiments incorporate bilayer channels consisting of an upper cover plate having a pattern of slots or holes of axially decreasing size and a lower fluid flow layer having channel widths substantially greater than the characteristic microscale dimensions of the patterned cover plate. The small dimensions of the cover plate holes afford large capillary pressure differentials while the larger dimensions of the lower region reduce viscous flow resistance.

  8. Fuel axial relocation in ballooning fuel rods. [PWR; BWR

    SciTech Connect (OSTI)

    Siefken, L.J.

    1983-01-01

    Fuel movement, in the longitudinal direction in ballooning fuel rods, shifts the position of heat generation and may cause an increase in cladding temperature in the ballooning region. This paper summarizes the axial fuel relocation data obtained in fuel rod tests conducted in the United States and the Federal Republic of Germany, describes a model for calculating fuel axial relocation, and gives a quantitative analysis of the impact of fuel relocation on cladding temperature. The amount of fuel relocation in 18 ballooned fuel rods was determined from neutron radiographs, niobium gamma decay counts, and photomicrographs. The fuel rods had burnups in the range of 0 to 35,000 MWd/t and cladding hoop strains varying from 0 to 72%.

  9. Design and optimization of a bi-axial vibration-driven electromagnetic...

    Office of Scientific and Technical Information (OSTI)

    Design and optimization of a bi-axial vibration-driven electromagnetic generator Citation Details In-Document Search Title: Design and optimization of a bi-axial vibration-driven ...

  10. Design of a Modular E-Core Flux Concentrating Axial Flux Machine...

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

    Design of a Modular E-Core Flux Concentrating Axial Flux Machine Preprint Tausif Husain, 1 ... Design of a Modular E-Core Flux Concentrating Axial Flux Machine Tausif Husain (1) Yilmaz ...

  11. The nucleon axial charge in full lattice QCD

    SciTech Connect (OSTI)

    Robert Edwards; George Fleming; P Hagler; John Negele; Konstantinos Orginos; Andrew Pochinsky; Dru Renner; David Richards; Wolfram Schroers

    2005-10-13

    The nucleon axial charge is calculated as a function of the pion mass in full QCD. Using domain wall valence quarks and improved staggered sea quarks, we present the first calculation with pion masses as light as 354 MeV and volumes as large as (3.5 fm)3. We show that finite volume effects are small for our volumes and that a constrained fit based on finite volume chiral perturbation theory agrees with experiment within 5% statistical errors.

  12. Paint coatings: Controlled field and chamber experiments

    SciTech Connect (OSTI)

    Edney, E.O.

    1989-04-01

    To determine the impact of pollution levels on the weathering rates of coatings, laboratory chamber experiments and controlled field exposures at North Carolina and Ohio sites were conducted in such a manner to separate the contributions due to dry deposition, wet deposition, precipitation pH, etc. The results of these studies confirm that acidic gases such as SO/sub 2/ and HNO/sub 3/, as well as acids within rain, promote the dissolution of alkaline components including CaCO/sub 3/, ZnO, and Al flake from paint films. It is unclear from these studies whether the removal of these components reduces the service life or protective properties of the paint film. Other researchers within the Coatings Effects Program are conducting subsequent analyses to determine micro-damage of these paints. The uptake of acidic gases to painted surfaces is a complex process that depends on several factors. The deposition rate of SO/sub 2/ to a wet, painted surface may be controlled by the level of oxidants such as H/sub 2/O/sub 2/.

  13. 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

    2014-12-09

    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.

  14. Coanda injection system for axially staged low emission combustors

    DOE Patents [OSTI]

    Evulet, Andrei Tristan; Varatharajan, Balachandar; Kraemer, Gilbert Otto; ElKady, Ahmed Mostafa; Lacy, Benjamin Paul

    2012-05-15

    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.

  15. Turbine component cooling channel mesh with intersection chambers

    DOE Patents [OSTI]

    Lee, Ching-Pang; Marra, John J

    2014-05-06

    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).

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

    SciTech Connect (OSTI)

    Abdikian, Alireza; Bagheri, Mehran

    2013-10-15

    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.

  17. Competition between modes with different axial structures in gyrotrons

    SciTech Connect (OSTI)

    Khutoryan, Eduard M.; Nusinovich, Gregory S.; Sinitsyn, Oleksandr V.

    2014-09-15

    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.

  18. 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.

    1995-05-01

    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.

  19. DEVELOPMENT OF TITANIUM NITRIDE COATING FOR SNS RING VACUUM CHAMBERS.

    SciTech Connect (OSTI)

    HE,P.; HSEUH,H.C.; MAPES,M.; TODD,R.; WEISS,D.

    2001-06-18

    The inner surface of the ring vacuum chambers of the US Spallation Neutron Source (SNS) will be coated with {approximately}100 nm of Titanium Nitride (TiN). This is to minimize the secondary electron yield (SEY) from the chamber wall, and thus avoid the so-called e-p instability caused by electron multipacting as observed in a few high-intensity proton storage rings. Both DC sputtering and DC-magnetron sputtering were conducted in a test chamber of relevant geometry to SNS ring vacuum chambers. Auger Electron Spectroscopy (AES) and Rutherford Back Scattering (RBS) were used to analyze the coatings for thickness, stoichiometry and impurity. Excellent results were obtained with magnetron sputtering. The development of the parameters for the coating process and the surface analysis results are presented.

  20. Ducted combustion chamber for direct injection engines and method

    DOE Patents [OSTI]

    Mueller, Charles

    2015-03-03

    An internal combustion engine includes an engine block having a cylinder bore and a cylinder head having a flame deck surface disposed at one end of the cylinder bore. A piston connected to a rotatable crankshaft and configured to reciprocate within the cylinder bore has a piston crown portion facing the flame deck surface such that a combustion chamber is defined within the cylinder bore and between the piston crown and the flame deck surface. A fuel injector having a nozzle tip disposed in fluid communication with the combustion chamber has at least one nozzle opening configured to inject a fuel jet into the combustion chamber along a fuel jet centerline. At least one duct defined in the combustion chamber between the piston crown and the flame deck surface has a generally rectangular cross section and extends in a radial direction relative to the cylinder bore substantially along the fuel jet centerline.

  1. Effects of outgassing of loader chamber walls on hydriding of...

    Office of Scientific and Technical Information (OSTI)

    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....

  2. MHK Technologies/Multi Resonant Chambers MRC 1000 | Open Energy...

    Open Energy Info (EERE)

    Water Column OWC principles Consists of 3 x 500kW independent chambers each with a Dresser Rand HydroAir turbine driving an induction generator Full power conversion system...

  3. Gas Electron Multiplier (GEM) Chamber Characteristics Test (Technical...

    Office of Scientific and Technical Information (OSTI)

    x 30cm chamber integrated with the SLAC-developed 64 channel kPiX analog readout chip. ... 1cm x 1cm pad granularity with 64 channel 2-D simultaneous readout using the kPiX chip. ...

  4. Carrying Semiautomatic Pistols with a Round in the Chamber

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

    1999-10-28

    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.

  5. Santa Fe Chamber of Commerce Business Awards Gala

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

    Santa Fe Chamber of Commerce Business Awards Gala Santa Fe Chamber of Commerce Business Awards Gala WHEN: Jun 04, 2015 5:30 PM - 7:30 PM WHERE: Skylight 139 West San Francisco Street, Santa Fe CATEGORY: Community INTERNAL: Calendar Login Event Description An event to recognize some of Santa Fe's best and brightest businesses in the following categories: Business Excellence, Small Business of the Year, Family Friendly Business, Green Business, and Woman Owned Business. Come dressed to impress for

  6. OSTIblog Articles in the Tennessee Chamber of Commerce and Industry Topic |

    Office of Scientific and Technical Information (OSTI)

    OSTI, US Dept of Energy Office of Scientific and Technical Information Tennessee Chamber of Commerce and Industry Topic TENNESSEE CHAMBER OF COMMERCE & INDUSTRY LAUDS OSTI by Kate Bannan 30 Jun, 2011 in Science Communications 4367 header_chamber.gif TENNESSEE CHAMBER OF COMMERCE & INDUSTRY LAUDS OSTI Read more about 4367 We are proud to note that OSTI was featured in the Tennessee Chamber of Commerce & Industry'ssummer issue of its newsletter, the Business Insider. The Chamber

  7. Radial force on the vacuum chamber wall during thermal quench in tokamaks

    SciTech Connect (OSTI)

    Pustovitov, V. D.

    2015-12-15

    The radial force balance during a thermal quench in tokamaks is analyzed. As a rule, the duration τ{sub tp} of such events is much shorter than the resistive time τ{sub w} of the vacuum chamber wall. Therefore, the perturbations of the magnetic field B produced by the evolving plasma cannot penetrate the wall, which makes different the magnetic pressures on its inner and outer sides. The goal of this work is the analytical estimation of the resulting integral radial force on the wall. The plasma is considered axially symmetric; for the description of radial forces on the wall, the results of V.D. Shafranov’s classical work [J. Nucl. Energy C 5, 251 (1963)] are used. Developed for tokamaks, the standard equilibrium theory considers three interacting systems: plasma, poloidal field coils, and toroidal field coils. Here, the wall is additionally incorporated with currents driven by ∂B/∂t≠0 accompanying the fast loss of the plasma thermal energy. It is shown that they essentially affect the force redistribution, thereby leading to large loads on the wall. The estimates prove that these loads have to be accounted for in the disruptive scenarios in large tokamaks.

  8. Lifetime survivability of contaminated target-chamber optics

    SciTech Connect (OSTI)

    Rainer, F.; Anderson, A.; Burnham, A.; Milam, D.; Turner, R.

    1996-11-01

    Target chambers used for Inertial Confinement Fusion (ICF) expose laser optics to a very hostile environment, not only from high-fluence laser irradiation but also x-ray irradiation and particulate debris from targets and chamber wall materials. Expendable debris shields provide the first line of defense to more costly optics upstream in the laser beam path to contaminants generated within the target chamber. However, the replacement of a large number of debris shields is also an expensive proposition so that extending their usable lifetime within the chamber is important. We have conducted tests to show that optics can both be cleaned and damaged by laser irradiation at 355 nm after being contaminated with potential chamber-wall materials such as B{sub 4}C and Al{sub 2}O{sub 3}. Such optics can survive from one to hundreds of laser shots, depending on degree of contamination and laser fluence levels. Similarly, we have studied the survivability of optics that have been exposed to direct contamination from representative target materials irradiated in the target chamber. We have also studied the effects on optics that were not directly exposed to targets, yet received secondary exposure from the above directly-exposed samples.

  9. Scalable Low-head Axial-type Venturi-flow Energy Scavenger | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Scalable Low-head Axial-type Venturi-flow Energy Scavenger Scalable Low-head Axial-type Venturi-flow Energy Scavenger Scalable Low-head Axial-type Venturi-flow Energy Scavenger 68e_pi_nmsu_prasad.ppt (4.89 MB) More Documents & Publications CX-011410: Categorical Exclusion Determination Water Power Program Peer Review Meeting Agenda Laboratory Demonstration of a New American Low-Head Hydropower Turbine

  10. Thermoacoustic mixture separation with an axial temperature gradient

    SciTech Connect (OSTI)

    Geller, Drew W; Swift, Gregory A

    2008-01-01

    The theory of thermoacoustic mixture separation is extended to include the effect of a nonzero axial temperature gradient. The analysis yields a new term in the second-order mole flux that is proportional to the temperature gradient and to the square of the volumetric velocity and is independent of the phasing of the wave. Because of this new term, thermoacoustic separation stops at a critical temperature gradient and changes direction above that gradient. For a traveling wave, this gradient is somewhat higher than that predicted by a simple four-step model. An experiment tests the theory for temperature gradients from 0 to 416 K/m in 50-50 He-Ar mixtures.

  11. Collimation of laser-produced plasmas using axial magnetic field

    SciTech Connect (OSTI)

    Roy, Amitava; Harilal, Sivanandan S.; Hassan, Syed M.; Endo, Akira; Mocek, Tomas; Hassanein, A.

    2015-06-01

    We investigated the expansion dynamics of laser-produced plasmas expanding into an axial magnetic field. Plasmas were generated by focusing 1.064 µm Nd:YAG laser pulses onto a planar tin target in vacuum and allowed to expand into a 0.5 T magnetic-filed where field lines were aligned along the plume expansion direction. Gated images employing intensified CCD showed focusing of the plasma plume, which were also compared with results obtained using particle-in-cell modelling methods. The estimated density and temperature of the plasma plumes employing emission spectroscopy revealed significant changes in the presence and absence of the 0.5T magnetic field. In the presence of the field, the electron temperature is increased with distance from the target, while the density showed opposite effects.

  12. Axial couplings and strong decay widths of heavy hadrons

    SciTech Connect (OSTI)

    William Detmold, C.-J. David Lin, Stefan Meinel

    2012-04-01

    We calculate the axial couplings of mesons and baryons containing a heavy quark in the static limit using lattice QCD. These couplings determine the leading interactions in heavy hadron chiral perturbation theory and are central quantities in heavy quark physics, as they control strong decay widths and the light-quark mass dependence of heavy hadron observables. Our analysis makes use of lattice data at six different pion masses, 227 MeV < m{sub {pi}} < 352 MeV, two lattice spacings, a = 0.085, 0.112 fm, and a volume of (2.7 fm){sup 3}. Our results for the axial couplings are g{sub 1} = 0.449(51), g{sub 2} = 0.84(20), and g{sub 3} = 0.71(13), where g{sub 1} governs the interaction between heavy-light mesons and pions and g{sub 2,3} are similar couplings between heavy-light baryons and pions. Using our lattice result for g{sub 3}, and constraining 1/m{sub Q} corrections in the strong decay widths with experimental data for {Sigma}{sub c}{sup (*)} decays, we obtain {Gamma}[{Sigma}{sub b}{sup (*)} {yields} {Lambda}{sub b} {pi}{sup {+-}}] = 4.2(1.0), 4.8(1.1), 7.3(1.6), 7.8(1.8) MeV for the {Sigma}{sub b}{sup +}, {Sigma}{sub b}{sup -}, {Sigma}{sub b}{sup *+}, {Sigma}{sub b}{sup *-} initial states, respectively. We also derive upper bounds on the widths of the {Xi}{sub b}{sup prime(*)} baryons.

  13. Dark matter limits froma 15 kg windowless bubble chamber

    SciTech Connect (OSTI)

    Szydagis, Matthew Mark; /Chicago U.

    2010-12-01

    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.

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

    SciTech Connect (OSTI)

    Benjamin Chase; Troy Unruh; Joy Rempe

    2014-06-01

    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.

  15. Inertial confinement fusion reaction chamber and power conversion system study

    SciTech Connect (OSTI)

    Maya, I.; Schultz, K.R.; Battaglia, J.M.; Buksa, J.J.; Creedson, R.L.; Erlandson, O.D.; Levine, H.E.; Roelant, D.F.; Sanchez, H.W.; Schrader, S.A.

    1984-09-01

    GA Technologies has developed a conceptual ICF reactor system based on the Cascade rotating-bed reaction chamber concept. Unique features of the system design include the use of low activation SiC in a reaction chamber constructed of box-shaped tiles held together in compression by prestressing tendons to the vacuum chamber. Circulating Li/sub 2/O granules serve as the tritium breeding and energy transport material, cascading down the sides of the reaction chamber to the power conversion system. The total tritium inventory of the system is 6 kg; tritium recovery is accomplished directly from the granules via the vacuum system. A system for centrifugal throw transport of the hot Li/sub 2/O granules from the reaction chamber to the power conversion system has been developed. A number of issues were evaluated during the course of this study. These include the response of first-layer granules to the intense microexplosion surface heat flux, cost effective fabrication of Li/sub 2/O granules, tritium inventory and recovery issues, the thermodynamics of solids-flow options, vacuum versus helium-medium heat transfer, and the tradeoffs of capital cost versus efficiency for alternate heat exchange and power conversion system option. The resultant design options appear to be economically competitive, safe, and environmentally attractive.

  16. Atmosphere contamination following repainting of a human hyperbaric chamber complex

    SciTech Connect (OSTI)

    Lillo, R.S.; Morris, J.W.; Caldwell, J.M.; Balk, D.M.; Flynn, E.T. )

    1990-09-01

    The Naval Medical Research Institute currently conducts hyperbaric research in a Man-Rated Chamber Complex (MRCC) originally installed in 1977. Significant engineering alterations to the MRCC and rusting of some of its interior sections necessitated repainting, which was completed in 1988. Great care was taken in selecting an appropriate paint (polyamide epoxy) and in ensuring correct application and curing procedures. Only very low levels of hydrocarbons were found in the MRCC atmosphere before initial pressurization after painting and curing. After pressurization, however, significant chemical contamination was found. The primary contaminants were aromatic hydrocarbons: xylenes (which were a major component of both the primer and topcoat paint) and ethyl benzene. The role that pressure played in stimulating off-gassing from the paint is not clear; the off-gassing rate was observed to be similar over a large range in chamber pressures from 1.6 to 31.0 atm abs. Scrubbing the chamber atmosphere with the chemical absorbent Purafil was effective in removing the contaminants. Contamination has been observed to slowly decline with chamber use and is expected to continue to improve with time. However, this contamination experience emphasizes the need for a high precision gas analysis program at any diving facility to ensure the safety of the breathing gas and chamber atmosphere.

  17. The PEP-II Lower Pressure HER Vacuum Chamber

    SciTech Connect (OSTI)

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

    2006-03-13

    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.

  18. Extreme-UV lithography vacuum chamber zone seal

    DOE Patents [OSTI]

    Haney, Steven J.; Herron, Donald Joe; Klebanoff, Leonard E.; Replogle, William C.

    2003-04-15

    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.

  19. Extreme-UV lithography vacuum chamber zone seal

    DOE Patents [OSTI]

    Haney, Steven J.; Herron, Donald Joe; Klebanoff, Leonard E.; Replogle, William C.

    2001-01-01

    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.

  20. Extreme-UV lithography vacuum chamber zone seal

    DOE Patents [OSTI]

    Haney, Steven J.; Herron, Donald Joe; Klebanoff, Leonard E.; Replogle, William C.

    2003-04-08

    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.

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

    SciTech Connect (OSTI)

    Kheiri, Golshad; Esmaeilzadeh, Mahdi

    2013-12-15

    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. Operation of drift chambers with helium based mixtures

    SciTech Connect (OSTI)

    Sharma, A. ); Sauli, F. )

    1994-08-01

    Helium based gas mixtures have been investigated for lowering multiple scattering contributions to the momentum resolution for intermediate energy particles. The relevant transport parameters, namely drift velocity and diffusion have been calculated for several mixtures and compared to standard argon based mixtures. Some fast, low diffusion mixtures have been identified. The small Lorentz angle computed make them promising candidates for drift chamber operation in magnetic fields. Measurements on high accuracy drift chambers in a test beam with a helium-DME (dimethyl ether) (70-30) mixture have resulted in a spatial resolution ranging from 70[mu]m to 100[mu]m.

  3. Fuel subassembly leak test chamber for a nuclear reactor

    DOE Patents [OSTI]

    Divona, Charles J.

    1978-04-04

    A container with a valve at one end is inserted into a nuclear reactor coolant pool. Once in the pool, the valve is opened by a mechanical linkage. An individual fuel subassembly is lifted into the container by a gripper; the valve is then closed providing an isolated chamber for the subassembly. A vacuum is drawn on the chamber to encourage gaseous fission product leakage through any defects in the cladding of the fuel rods comprising the subassembly; this leakage may be detected by instrumentation, and the need for replacement of the assembly ascertained.

  4. Negative particle planar and axial channeling and channeling collimation

    SciTech Connect (OSTI)

    Carrigan, Richard A., Jr.; /Fermilab

    2009-12-01

    While information exists on high energy negative particle channeling there has been little study of the challenges of negative particle bending and channeling collimation. Partly this is because negative dechanneling lengths are relatively much shorter. Electrons are not particularly useful for investigating negative particle channeling effects because their material interactions are dominated by channeling radiation. Another important factor is that the current central challenge in channeling collimation is the proton-proton Large Hadron Collider (LHC) where both beams are positive. On the other hand in the future the collimation question might reemerge for electon-positron or muon colliders. Dechanneling lengths increase at higher energies so that part of the negative particle experimental challenge diminishes. In the article different approaches to determining negative dechanneling lengths are reviewed. The more complicated case for axial channeling is also discussed. Muon channeling as a tool to investigate dechanneling is also discussed. While it is now possible to study muon channeling it will probably not illuminate the study of negative dechanneling.

  5. An analytical model of axial compressor off-design performance

    SciTech Connect (OSTI)

    Camp, T.R.; Horlock, J.H. . Whittle Lab.)

    1994-07-01

    An analysis is presented of the off-design performance of multistage axial-flow compressors. It is based on an analytical solution, valid for small perturbations in operating conditions from the design point, and provides an insight into the effects of choices made during the compressor design process on performance and off-design stage matching. It is shown that the mean design value of stage loading coefficient ([psi] = [Delta]h[sub 0]/U[sup 2]) has a dominant effect on off-design performance, whereas the stage-wise distribution of stage loading coefficient and the design value of flow coefficient have little influence. The powerful effects of variable stator vanes on stage-matching are also demonstrated and these results are shown to agree well with previous work. The slope of the working line of a gas turbine engine, overlaid on overall compressor characteristics, is shown to have a strong effect on the off-design stage-matching through the compressor. The model is also used to analyze design changes to the compressor geometry and to show how errors in estimates of annulus blockage, decided during the design process, have less effect on compressor performance than has previously been thought.

  6. Modeling shrouded stator cavity flows in axial-flow compressors

    SciTech Connect (OSTI)

    Wellborn, S.R.; Tolchinsky, I.; Okiishi, T.H.

    2000-01-01

    Experiments and computational analyses were completed to understand the nature of shrouded stator cavity flows. From this understanding, a one-dimensional model of the flow through shrouded stator cavities was developed. This model estimates the leakage mass flow, temperature rise, and angular momentum increase through the cavity, given geometry parameters and the flow conditions at the interface between the cavity and primary flow path. This cavity model consists of two components, one that estimates the flow characteristics through the labyrinth seals and the other that predicts the transfer of momentum due to windage. A description of the one-dimensional model is given. The incorporation and use of the one-dimensional model in a multistage compressor primary flow analysis tool is described. The combination of this model and the primary flow solver was used to reliably simulate the significant impact on performance of the increase of hub seal leakage in a twelve-stage axial-flow compressor. Observed higher temperatures of the hub region fluid, different stage matching, and lower overall efficiencies and core flow than expected could be correctly linked to increased hub seal clearance with this new technique. The importance of including these leakage flows in compressor simulations is shown.

  7. 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

  8. Modeling Chamber Transport for Heavy-Ion Fusion

    SciTech Connect (OSTI)

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

    2002-08-02

    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.

  9. 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.

    2002-10-01

    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.

  10. METALLIZATION OF SNS RING INJECTION KICKER CERAMIC CHAMBERS.

    SciTech Connect (OSTI)

    HE,P.; HSEUH,H.C.; TODD,R.J.

    2002-06-03

    Ceramic chambers will be used in the pulsed kicker magnets for the injection of H{sup -} into the Spallation Neutron Source (SNS) accumulator ring, to avoid shielding of a fast-changing external magnetic field by metallic chamber walls and to reduce eddy current heating. The inner surfaces of the ceramic chambers will be coated with a conductive layer, possibly titanium (Ti) or copper (Cu) with a titanium nitride (TiN) overlayer, to reduce the beam coupling impedance, provide passage for beam image current and to reduce the secondary electron yields. This paper describes the development of sputtering method for the 0.83m long 16cm inner diameter (ID) ceramic chambers. Coatings of Ti, Cu and TiN with thickness up to 10 {micro}m were produced by means of DC magnetron sputtering. The difficulty of coating insulators was overcome with the introduction of an anode screen. Films with good adhesion, uniform longitudinal thickness, and conductivity were produced.

  11. Axial couplings of heavy hadrons from domain-wall lattice QCD

    SciTech Connect (OSTI)

    W. Detmold, C.J.D. Lin, S. Meinel

    2011-12-01

    We calculate matrix elements of the axial current for static-light mesons and baryons in lattice QCD with dynamical domain wall fermions. We use partially quenched heavy hadron chiral perturbation theory in a finite volume to extract the axial couplings g{sub 1}, g{sub 2}, and g{sub 3} from the data. These axial couplings allow the prediction of strong decay rates and enter chiral extrapolations of most lattice results in the b sector. Our calculations are performed with two lattice spacings and with pion masses down to 227 MeV.

  12. Axial current generation by P-odd domains in QCD matter

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Iatrakis, Ioannis; Yin, Yi; Lin, Shu

    2015-06-23

    The dynamics of topological domains which break parity (P) and charge-parity (CP) symmetry of QCD are studied. We derive in a general setting that those local domains will generate an axial current and quantify the strength of the induced axial current. Thus, our findings are verified in a top-down holographic model. The relation between the real time dynamics of those local domains and the chiral magnetic field is also elucidated. We finally argue that such an induced axial current would be phenomenologically important in a heavy-ion collisions experiment.

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

    SciTech Connect (OSTI)

    Dongarra, Jack J.; Tomov, Stanimire

    2014-03-24

    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.

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

    DOE Patents [OSTI]

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

    1982-10-28

    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.

  15. Cladding axial elongation models for FRAP-T6. [PWR; BWR

    SciTech Connect (OSTI)

    Shah, V.N.; Carlson, E.R.; Berna, G.A.

    1983-01-01

    This paper presents a description of the cladding axial elongation models developed at the Idaho National Engineering Laboratory (INEL) for use by the FRAP-T6 computer code in analyzing the response of fuel rods during reactor transients in light water reactors (LWR). The FRAP-T6 code contains models (FRACAS-II subcode) that analyze the structural response of a fuel rod including pellet-cladding-mechanical-interaction (PCMI). Recently, four models were incorporated into FRACAS-II to calculate cladding axial deformation: (a) axial PCMI, (b) trapped fuel stack, (c) fuel relocation, and (d) effective fuel thermal expansion. Comparisons of cladding axial elongation measurements from two experiments with the corresponding FRAP-T6 calculations are presented.

  16. Determination of trace elements in soils with an axial sequential ICP

    SciTech Connect (OSTI)

    Shkolnik, J.; Flajnik, C.

    1995-12-31

    Over the past few years the popularity of axial viewed ICP has increased greatly. The major claimed advantage of axial ICP is improvement in detection limits by an order of magnitude over radial viewed plasmas. It has also been noted however, that axial ICP suffers from greater chemical and ionization interferences than radial ICP, making it less desirable for samples with a {open_quotes}matrix{close_quotes}. In this paper we will describe the determination of a number of trace paper elements in soil samples by axial ICP. The chemical and ionization interferences will be examined and the accuracy and precision will be evaluated. Comparisons to the same determinations done on a radial ICP with ultrasonic nebulizer will also be discussed.

  17. 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.; Vretenar, D.

    2009-08-26

    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.

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

    SciTech Connect (OSTI)

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

    2010-02-10

    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.

  19. Chamber for the optical manipulation of microscopic particles

    DOE Patents [OSTI]

    Buican, Tudor N.; Upham, Bryan D.

    1992-01-01

    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.

  20. Combustion chamber and thermal vapor stream producing apparatus and method

    DOE Patents [OSTI]

    Sperry, John S.; Krajicek, Richard W.; Cradeur, Robert R.

    1978-01-01

    A new and improved method and apparatus for burning a hydrocarbon fuel for producing a high pressure thermal vapor stream comprising steam and combustion gases for injecting into a subterranean formation for the recovery of liquefiable minerals therefrom, wherein a high pressure combustion chamber having multiple refractory lined combustion zones of varying diameters is provided for burning a hydrocarbon fuel and pressurized air in predetermined ratios injected into the chamber for producing hot combustion gases essentially free of oxidizing components and solid carbonaceous particles. The combustion zones are formed by zones of increasing diameters up a final zone of decreasing diameter to provide expansion zones which cause turbulence through controlled thorough mixing of the air and fuel to facilitate complete combustion. The high pressure air and fuel is injected into the first of the multiple zones where ignition occurs with a portion of the air injected at or near the point of ignition to further provide turbulence and more complete combustion.

  1. Recommendations for Addressing Axial Burnup in the PWR Burnup Credit Analyses

    SciTech Connect (OSTI)

    Wagner, J.C.

    2002-10-23

    This report presents studies performed to support the development of a technically justifiable approach for addressing the axial-burnup distribution in pressurized-water reactor (PWR) burnup-credit criticality safety analyses. The effect of the axial-burnup distribution on reactivity and proposed approaches for addressing the axial-burnup distribution are briefly reviewed. A publicly available database of profiles is examined in detail to identify profiles that maximize the neutron multiplication factor, k{sub eff}, assess its adequacy for PWR burnup credit analyses, and investigate the existence of trends with fuel type and/or reactor operations. A statistical evaluation of the k{sub eff} values associated with the profiles in the axial-burnup-profile database was performed, and the most reactive (bounding) profiles were identified as statistical outliers. The impact of these bounding profiles on k{sub eff} is quantified for a high-density burnup credit cask. Analyses are also presented to quantify the potential reactivity consequence of loading assemblies with axial-burnup profiles that are not bounded by the database. The report concludes with a discussion on the issues for consideration and recommendations for addressing axial burnup in criticality safety analyses using burnup credit for dry cask storage and transportation.

  2. Evaluation of axial and lateral modal superposition for general 3D drilling riser analysis

    SciTech Connect (OSTI)

    Burgdorf, O. Jr.

    1996-12-31

    A 3D partially non-linear transient fully-coupled riser analysis method is evaluated which uses modal superposition of independently extracted lateral and axial modes. Many lateral modes are combined with a lesser number axial modes to minimize adverse time step requirements typically induced by axial flexibility in direct time integration of beam-column elements. The reduced computer time option enables much faster parametric analysis of hang-off, as well as other connected drilling environments normally examined. Axial-lateral coupling is explicitly enforced and, resonance fidelity is preserved when excitation is near or coincident with axial natural periods. Reasonable correlation is shown with envelopes of test case dynamic responses published by API. Applicability of the method is limited by linearity assumptions indigenous to modal representation of dynamic deflections relative to a mean deflected shape. Sensitivities of incipient buckling during hang-off to axial damping and stiffness are described for an example 6,000 ft. deep composite drilling riser system.

  3. Using sputter coated glass to stabilize microstrip gas chambers

    DOE Patents [OSTI]

    Gong, Wen G.

    1997-01-01

    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.

  4. The Mark III vertex chamber: Studies using DME

    SciTech Connect (OSTI)

    Pitman, D.

    1987-04-01

    Studies have been performed using a prototype of a pressurized wire vertex chamber with 8 mm diameter straw geometry. A 35 ..mu..m spatial resolution using dimethyl ether (DME) at 1 bar and 30 ..mu..m using argon ethane (50/50 mixture) at 4 bar was obtained. Preliminary studies show the DME to adversely affect such materials as aluminized Mylar and Delrin.

  5. Luis Alvarez, the Hydrogen Bubble Chamber, Tritium, and Dinosaurs

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

    Luis Alvarez, the Hydrogen Bubble Chamber, Tritium, and Dinosaurs Resources with Additional Information * Patents Luis Alvarez Courtesy Lawrence Berkeley National Laboratory 'Luis W. Alvarez was an adventurer physicist. The two terms may seem an odd combination until one considers Alvarez's career. A member of the National Inventor's Hall of Fame, Alvarez developed the proton linear accelerator, patented three types of radar still used today, designed an instrument that for 15 years served as

  6. Azimuthal Instabilities in Annular Combustion Chambers | Argonne Leadership

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

    Computing Facility Azimuthal Instabilities in Annular Combustion Chambers Authors: Wolf, P., Staffelbach, G., Balakrishnan, R., Roux, A., Poinsot, T. Large Eddy Simulations (LES) of a full annular helicopter gas turbine combustor have been performed. Emphasis is placed on the azimuthal mode that often appears in real configurations. The current LES are shown to capture these self-excited modes, with limited impact of the grid resolution. The structure of the azimuthal mode is discussed and

  7. Continuous Flow Diffusion Chamber Measurements of IN Concentration

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

    Flow Diffusion Chamber (CFDC) Measurements of IN Concentration Concentrations of Ice-Nucleating Aerosol (IN) as a function of Temperature and %Supersaturation Sarah Brooks and Andrew Glen, Texas A&M University Archived CFDC Data Flights April 8 through end of ISDAC ... CFDC operating conditions vary Date Flight Num 20080331 Flight 08 20080401 Flight 09 & 10 20080404 Flight 11 & 12 20080405 Flight 13 & 14 20080408 Flight 15, 16 & 17 20080413 Flight 18 & 19 20080414 Flight

  8. LAYOUT AND SIZING OF ESF ALCOVES AND REFUGE CHAMBERS

    SciTech Connect (OSTI)

    John Beesley and Romeo S. Jurani

    1995-08-25

    The purpose of this analysis is to establish size requirements and approximate locations of Exploratory Studies Facility (ESF) test and operations alcoves, including refuge chambers during construction of the Topopah Spring (TS) loop. Preliminary conceptual layouts for non-deferred test alcoves will be developed to examine construction feasibility based on current test plans and available equipment. The final location and configuration layout for alcoves will be developed when in-situ rock conditions can be visually determined. This will be after the TBM has excavated beyond the alcove location and the rock has been exposed. The analysis will examine the need for construction of walkways and electrical alcoves in the ramps and main drift. Niches that may be required to accommodate conveyor booster drives and alignments are not included in this analysis. The analysis will develop design criteria for refuge chambers to meet MSHA requirements and will examine the strategic location of refuge chambers based on their potential use in various ESF fire scenarios. This document supersedes DI:BABE00000-01717-0200-00003 Rev 01, ''TS North Ramp Alcove and Stubout Location Analysis'' in its entirety (Reference 5-6).

  9. Dark Matter Search Results from the PICO-60 CF$_3$I Bubble Chamber...

    Office of Scientific and Technical Information (OSTI)

    Dark Matter Search Results from the PICO-60 CF3I Bubble Chamber Citation Details In-Document Search Title: Dark Matter Search Results from the PICO-60 CF3I Bubble Chamber...

  10. Los Alamos honored by Española Valley Chamber of Commerce

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

    LANL Honored By Española Valley Chamber of Commerce Community Connections: Your link to news and opportunities from Los Alamos National Laboratory Latest Issue: September 1, 2016 all issues All Issues » submit Los Alamos honored by Española Valley Chamber of Commerce The Espanola Valley Chamber of Commerce recognized the Lab for its support to the chamber and the entire Espanola Valley with a President's Choice Award. February 1, 2013 dummy image Read our archives. Contacts Editor Linda

  11. CNS Joins Oak Ridge Chamber in Nashville | Y-12 National Security Complex

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

    Joins Oak Ridge Chamber ... CNS Joins Oak Ridge Chamber in Nashville Posted: April 13, 2016 - 12:25pm Tennessee Governor Bill Haslam (front row center) greets Oak Ridge business leaders during Oak Ridge Chamber of Commerce's Day on the Hill. Also pictured: (back row) Kelly Callison, Gene Patterson, Rick Chinn, Ben Andrews, (front row) Stacy Myers, Parker Hardy, Patricia Myers and Lisa Copeland. Consolidated Nuclear Security and other area businesses recently joined the Oak Ridge Chamber of

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

    SciTech Connect (OSTI)

    Daugherty, W.

    2013-09-30

    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.

  13. Possibility of using cylindrical ionization chambers for percent depth-dose measurements in clinical electron beams

    SciTech Connect (OSTI)

    Ono, Takeshi; Araki, Fujio; Yoshiyama, Fumiaki

    2011-08-15

    Purpose: This study investigated the possibility of using cylindrical ionization chambers for percent depth-dose (PDD) measurements in high-energy clinical electron beams. Methods: The cavity correction factor, P{sub cav}, for cylindrical chambers with various diameters was calculated as a function of depth from the surface to R{sub 50}, in the energy range of 6-18 MeV electrons with the EGSnrc C ++ -based user-code CAVITY. The results were compared with those for IBA NACP-02 and PTW Roos parallel-plate ionization chambers. The effective point of measurement (EPOM) for the cylindrical chamber and the parallel-plate chamber was positioned according to the IAEA TRS-398 code of practice. The overall correction factor, P{sub Q}, and the percent depth-ionization (PDI) curve for a PTW30013 Farmer-type chamber were also compared with those of NACP-02 and Roos chambers. Results: The P{sub cav} values at depths between the surface and R{sub 50} for cylindrical chambers were all lower than those with parallel-plate chambers. However, the variation in depth for cylindrical chambers equal to or less than 4 mm in diameter was equivalent to or smaller than that for parallel-plate chambers. The P{sub Q} values for the PTW30013 chamber mainly depended on P{sub cav}, and for parallel-plate chambers depended on the wall correction factor, P{sub wall}, rather than P{sub cav}. P{sub Q} at depths from the surface to R{sub 50} for the PTW30013 chamber was consequently a lower value than that with parallel-plate chambers. However, the variation in depth was equivalent to that of parallel-plate chambers at electron energies equal to or greater than 9 MeV. The shift to match calculated PDI curves for the PTW30013 chamber and water (perturbation free) varied from 0.65 to 0 mm between 6 and 18 MeV beams. Similarly, the shifts for NACP-02 and Roos chambers were 0.5-0.6 mm and 0.2-0.3 mm, respectively, and were nearly independent of electron energy. Conclusions: Calculated PDI curves for PTW

  14. Performance parameters of a liquid filled ionization chamber array

    SciTech Connect (OSTI)

    Poppe, B.; Stelljes, T. S.; Looe, H. K.; Chofor, N.; Harder, D.; Willborn, K.

    2013-08-15

    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

  15. 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) ,

    2011-03-08

    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.

  16. Design of the OMEGA Laser Target Chamber Tritium Removal System

    SciTech Connect (OSTI)

    Nobile, Arthur; Reichert, Heidi; Janezic, Roger T.; Harding, David R.; Lund, Lance D.; Shmayda, Walter T.

    2003-06-15

    Preparations are currently underway at the OMEGA laser at the University of Rochester Laboratory for Laser Energetics (UR/LLE) to conduct direct drive laser implosion campaigns with inertial confinement fusion targets containing deuterium-tritium (DT) cryogenic ice layers. The OMEGA Cryogenic Target Handling System will fill plastic targets with high-pressure DT (150 MPa) at 300 to 500 K, cool them down to cryogenic temperature (<25 K), form the DT ice layer, and transport the targets to the OMEGA laser target chamber. Targets will then be shot with the 60-beam 30-kJ OMEGA laser. A tritium removal system has been designed to remove tritium from effluents associated with operation of the target chamber and its associated diagnostic antechambers, vacuum pumping systems, and target insertion systems. The design of the target chamber tritium removal system (TCTRS) is based on catalytic oxidation of DT and tritiated methane to tritiated water (DTO), followed by immobilization of DTO on molecular sieves. The design of the TCTRS presented a challenge due to the low tritium release limits dictated by the tritium license at UR/LLE. Aspen Plus, a commercial software package intended for the simulation and design of chemical processing systems operating at steady state, was used to simulate and design the TCTRS. A second commercial software package, Aspen ADSIM, was used to simulate and design the TCTRS molecular sieve beds, which operate at unsteady state. In this paper, we describe the design of the TCTRS and the benefits that were realized by use of the Aspen Plus and Aspen ADSIM software packages.

  17. Polymer insulator profiles evaluated in a fog chamber

    SciTech Connect (OSTI)

    Gorur, R.S. . Dept. of Electrical and Computer Engineering); Cherney, E.A. ); Hackam, R. )

    1990-04-01

    This paper presents the results of fog chamber experiments done to examine the tracking and erosion performance of polymer insulator profiles. The effect of weathershed material, construction, orientation, and ac and dc voltage are examined. Correlation between cylindrical rod specimens of materials and insulator profiles is shown. The protected leakage path provided by the weathershed is found to play a major role in the tracking and erosion performance of polymer insulators. The resistance to tracking and erosion of insulator profiles with dc is shown to be reduced in comparison to ac. Cylindrical rods of material yielded the same ranking of material performance as insulator profiles but in a shorter time.

  18. An aging study of wire chambers with dimethyl ether

    SciTech Connect (OSTI)

    Jibaly, M.; Chrusch, P. Jr.; Hilgenberg, G.; Majewski, S.; Wojcik, R.; Sauli, F.; Gaudaen, J.

    1989-02-01

    The authors report results on the aging of different types of resistive and non-resistive wires in wire chambers filled with dimethyl ether (DME) of varying degrees of purity. Among the Freon impurities detected in our DME batches, only Freon-11 was found to contribute to the aging process. Of the resistive wires, Nicotin and Stablohm produced fast aging, whereas stainless steel withstood extended irradiation in purified DME (up to 1 C/cm) without any apparent damage. Gold-plated tungsten and molybdenum wires produced results comparable to those of the stainless steel.

  19. Argon Time Projection Chamber(LArTPC) Data Jessica Esquivel

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

    Processing Techniques applied to Liquid Argon Time Projection Chamber(LArTPC) Data Jessica Esquivel On Behalf of the MicroBooNE Collaboration Syracuse University Advisor: Mitch Soderberg 2 Outline ● LArTPC Technology ● MicroBooNE Overview ● What is Image Processing? ● Image Processing on MicroBooNE Data ● Future Directions 3 LArTPC Technology Credit: Jonathan Asaadi 4 LArTPC Technology 5 MicroBooNE Overview ● MicroBooNE is a 150 ton(cryostat) ~90 ton LArTPC ● TPC dimensions - 10.3m

  20. Theoretical study of energy deposition in ionization chambers for tritium measurements

    SciTech Connect (OSTI)

    Chen, Zhilin; Peng, Shuming; Meng, Dan; He, Yuehong; Wang, Heyi

    2013-10-15

    Energy deposition in ionization chambers has been theoretically studied for tritium measurements in gaseous form. A one-dimension model is introduced to establish the quantitative relationship between energy deposition rate and many factors, including carrier gas, gas pressure, wall material, chamber size, and gas temperature. Energy deposition rate has been calculated at pressure varying from 5 kPa to 500 kPa based on some approximations. It is found that energy deposition rate varies greatly for different parameters, especially at low gas pressure. For the same chamber, energy deposition rate in argon is much higher than in deuterium, as much as 70.7% higher at 5 kPa. Gold plated chamber gives highest energy deposition rate in the calculations while aluminum chamber results in the lowest. As chamber size gets smaller, β ray emitted by tritium will deposit less energy in the sensitive region of the chamber. For chambers flowing through with the same gas, energy deposition rate in a 10 L chamber is 23.9% higher than in a 0.05 L chamber at 5 kPa. Gas temperature also places slight influence on energy deposition rate, and 373 K will lead to 6.7% lower deposition rate than 233 K at 5 kPa. In addition, experiments have been performed to obtain energy deposition rate in a gold plated chamber, which show good accordance with theoretical calculations.

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

    DOE Patents [OSTI]

    Mashey, Thomas Charles

    2002-01-01

    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.

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

    DOE Patents [OSTI]

    Haas, Wendall M. B.

    1985-01-01

    A convoluted flexible support structure is provided which is capable of supplying a lateral to axial spring rate in excess of 1,000 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.

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

    DOE Patents [OSTI]

    Haas, W.M.B.

    1983-06-23

    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.

  4. Gapless excitations of axially symmetric vortices in systems with tensorial order parameter

    SciTech Connect (OSTI)

    Peterson, Adam J.; Shifman, Mikhail

    2014-09-15

    We extend the results of previous work on vortices in systems with tensorial order parameters. Specifically, we focus our attention on systems with a Ginzburg–Landau free energy with a global U(1){sub P}×SO(3){sub S}×SO(3){sub L} symmetry in the phase, spin and orbital degrees of freedom. We consider axially symmetric vortices appearing on the spin–orbit locked SO(3){sub S+L} vacuum. We determine the conditions required on the Ginzburg–Landau parameters to allow for an axially symmetric vortex with off diagonal elements in the order parameter to appear. The collective coordinates of the axial symmetric vortices are determined. These collective coordinates are then quantized using the time dependent Ginzburg–Landau free energy to determine the number of gapless modes propagating along the vortex.

  5. Fuel, lubricant and additive effects in combustion chamber deposit formation

    SciTech Connect (OSTI)

    Kelemen, S.R.; Homan, H.S.

    1996-10-01

    CCD causes octane requirement increase (ORI) and can potentially contributes to exhaust emissions and combustion chamber deposit interference (CCDI). Experiments were conducted to identify the separate fuel, lubricant and additive contributions to the amount and composition of CCD. CCD originates from multiple sources. Gasoline hydrocarbon components, gasoline additives, engine lubricant, and atmospheric nitrogen contribute to CCD in different ways. With some fuels the engine lubricant is the main contributor to CCD and this is shown by the high ash level in the CCD. For other fuels CCD is predominantly organic. Significant amounts of nitrogen were found in the CCD even when the fuel and lubricant were nitrogen free. The pyrolysis reactivity of different CCDs was studied to gain an understanding about the transformations that potentially happen over longer times and lower temperatures on the combustion chamber walls. In all cases during mild pyrolysis (375{degrees}C) there was a substantial increase in the level of aromatic carbon and a decrease in the level of organic oxygen. The largest increases in the amount of aromatic carbon occurred for CCDs that were the least aromatic.

  6. Atmospheric-pressure plasma decontamination/sterilization chamber

    DOE Patents [OSTI]

    Herrmann, Hans W.; Selwyn, Gary S.

    2001-01-01

    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.

  7. Slag monitoring system for combustion chambers of steam boilers

    SciTech Connect (OSTI)

    Taler, J.; Taler, D.

    2009-07-01

    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.

  8. Sealable femtoliter chamber arrays for cell-free biology

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Retterer, Scott T.; Fowlkes, Jason Davidson; Collier, Charles Patrick; Simpson, Michael L.; Norred, Sarah Elizabeth; Caveney, Patrick M.; Boreyko, Jonathan B.

    2015-03-11

    Cell-free systems provide a flexible platform for probing specific networks of biological reactions isolated from the complex resource sharing (e.g. global gene expression, cell division) encountered within living cells. However, such systems, used in conventional macro-scale bulk reactors, often fail to exhibit the dynamic behaviors and efficiencies characteristic of their living micro-scale counterparts. Understanding the impact of internal cell structure and scale on reaction dynamics is crucial to understanding complex gene networks. Here we report a microfabricated device that confines cell-free reactions in cellular scale volumes while allowing flexible characterization of the enclosed molecular system. This multilayered poly(dimethylsiloxane) (PDMS) devicemore » contains femtoliter-scale reaction chambers on an elastomeric membrane which can be actuated (open and closed). When actuated, the chambers confine Cell-Free Protein Synthesis (CFPS) reactions expressing a fluorescent protein, allowing for the visualization of the reaction kinetics over time using time-lapse fluorescent microscopy. Lastly, we demonstrate how this device may be used to measure the noise structure of CFPS reactions in a manner that is directly analogous to those used to characterize cellular systems, thereby enabling the use of noise biology techniques to characterize CFPS gene circuits and their interactions with the cell-free environment.« less

  9. Wire-chamber radiation detector with discharge control

    DOE Patents [OSTI]

    Perez-Mendez, V.; Mulera, T.A.

    1982-03-29

    A wire chamber; radiation detector has spaced apart parallel electrodes and grids defining an ignition region in which charged particles or other ionizing radiations initiate brief localized avalanche discharges and defining an adjacent memory region in which sustained glow discharges are initiated by the primary discharges. Conductors of the grids at each side of the memory section extend in orthogonal directions enabling readout of the X-Y coordinates of locations at which charged particles were detected by sequentially transmitting pulses to the conductors of one grid while detecting transmissions of the pulses to the orthogonal conductors of the other grid through glow discharges. One of the grids bounding the memory region is defined by an array of conductive elements each of which is connected to the associated readout conductor through a separate resistance. The wire chamber avoids ambiguities and imprecisions in the readout of coordinates when large numbers of simultaneous or; near simultaneous charged particles have been detected. Down time between detection periods and the generation of radio frequency noise are also reduced.

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

    SciTech Connect (OSTI)

    Lee, Y.H.Y.

    1998-05-01

    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.

  11. A simple model simulating a fan as a source of axial and circumferential body forces

    Energy Science and Technology Software Center (OSTI)

    2002-07-01

    This software can be used in a computational fluids dynamics (CFD) code to represent a fan as a source of axial and circumferential body forces. The combined software can be used effectively in car design analyses that involve many underhood thermal management simulations. FANMOD uses as input the rotational speed of the fan, geometric fan data, and the lift and drag coefficients of the blades, and predicts the body forces generated by the fan inmore » the axial and circumferential directions. These forces can be used as momentum forces in a CFD code to simulate the effect of the fan in an underhood thermal management simulation.« less

  12. Conceptual Design Report for the Extreme Ecosystems Test Chambers

    SciTech Connect (OSTI)

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

    1998-12-01

    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.

  13. Readout of TPC Tracking Chambers with GEMs and Pixel Chip

    SciTech Connect (OSTI)

    Kadyk, John; Kim, T.; Freytsis, M.; Button-Shafer, J.; Kadyk, J.; Vahsen, S.E.; Wenzel, W.A.

    2007-12-21

    Two layers of GEMs and the ATLAS Pixel Chip, FEI3, have been combined and tested as a prototype for Time Projection Chamber (TPC) readout at the International Linear Collider (ILC). The double-layer GEM system amplifies charge with gain sufficient to detect all track ionization. The suitability of three gas mixtures for this application was investigated, and gain measurements are presented. A large sample of cosmic ray tracks was reconstructed in 3D by using the simultaneous timing and 2D spatial information from the pixel chip. The chip provides pixel charge measurement as well as timing. These results demonstrate that a double GEM and pixel combination, with a suitably modified pixel ASIC, could meet the stringent readout requirements of the ILC.

  14. Imaging performance of a multiwire proportional-chamber positron camera

    SciTech Connect (OSTI)

    Perez-Mandez, V.; Del Guerra, A.; Nelson, W.R.; Tam, K.C.

    1982-08-01

    A new design - fully three-dimensional - Positron Camera is presented, made of six MultiWire Proportional Chamber modules arranged to form the lateral surface of a hexagonal prism. A true coincidence rate of 56000 c/s is expected with an equal accidental rate for a 400 ..mu..Ci activity uniformly distributed in a approx. 3 l water phantom. A detailed Monte Carlo program has been used to investigate the dependence of the spatial resolution on the geometrical and physical parameters. A spatial resolution of 4.8 mm FWHM has been obtained for a /sup 18/F point-like source in a 10 cm radius water phantom. The main properties of the limited angle reconstruction algorithms are described in relation to the proposed detector geometry.

  15. Effects of acidic deposition on paint: A chamber study

    SciTech Connect (OSTI)

    Spence, J.W.; Lemmons, T.J.; Hou, Y.; Schadt, R.J.; Fornes, R.E.

    1993-08-01

    Exterior acrylic latex and alkyd architectural coatings were exposed to different conditions in a chamber exposure system involving simulated sunlight, dew, and photochemical smog-containing sulfur dioxide (SO2). A simulated sunlight exposure of the coating films in the presence of clean air was also incorporated into the experimental design. Changes in surface features after 1,370 hours of exposure were characterized by scanning electron microscope (SEM) and energy dispersive analysis of x-rays (EDAX). Gaseous species that deposited to the films were determined by ion chromatography of the dew collections. Color-change measurements of the exposed films were recorded as Delta E values. Latex and alkyd films that were formulated with calcium carbonate (CACO3) as an extender pigment were found to undergo the most change in surface features, composition, and color.

  16. Inducing chaos by breaking axial symmetry in a black hole magnetosphere

    SciTech Connect (OSTI)

    Kopáček, O.; Karas, V.

    2014-06-01

    While the motion of particles near a rotating, electrically neutral (Kerr), and charged (Kerr-Newman) black hole is always strictly regular, a perturbation in the gravitational or the electromagnetic field generally leads to chaos. The transition from regular to chaotic dynamics is relatively gradual if the system preserves axial symmetry, whereas non-axisymmetry induces chaos more efficiently. Here we study the development of chaos in an oblique (electro-vacuum) magnetosphere of a magnetized black hole. Besides the strong gravity of the massive source represented by the Kerr metric, we consider the presence of a weak, ordered, large-scale magnetic field. An axially symmetric model consisting of a rotating black hole embedded in an aligned magnetic field is generalized by allowing an oblique direction of the field having a general inclination with respect to the rotation axis of the system. The inclination of the field acts as an additional perturbation to the motion of charged particles as it breaks the axial symmetry of the system and cancels the related integral of motion. The axial component of angular momentum is no longer conserved and the resulting system thus has three degrees of freedom. Our primary concern within this contribution is to find out how sensitive the system of bound particles is to the inclination of the field. We employ the method of the maximal Lyapunov exponent to distinguish between regular and chaotic orbits and to quantify their chaoticity. We find that even a small misalignment induces chaotic motion.

  17. Three-dimensional model and simulation of vacuum arcs under axial magnetic fields

    SciTech Connect (OSTI)

    Wang Lijun; Jia Shenli; Zhou Xin; Wang Haijing; Shi Zongqian

    2012-01-15

    In this paper, a three-dimensional (3d) magneto-hydro-dynamic (MHD) model of axial magnetic field vacuum arcs (AMFVAs) is established. Based on this model, AMFVAs are simulated and analyzed. Three-dimensional spatial distributions of many important plasma parameters and electric characteristics in AMFVAs can be obtained, such as ion number density, ion temperature, electron temperature, plasma pressure, current densities along different directions (x, y, and z), ion velocities along different directions, electric fields strength along different directions, and so on. Simulation results show that there exist significant spiral-shaped rotational phenomena in the AMFVAs, this kind of rotational phenomenon also can be verified by the many related experiments (AMFVAs photographs, especially for stronger AMF strength). For current simulation results of AMFVAs, the maximal rotational velocity at anode side is about 1100 m/s. Radial electric field is increased from arc center to arc edge; axial electric field is decreased from cathode side to anode side. Radial electric field at arc edge can be larger than axial electric field. Azimuthal electric field in most regions is much smaller than radial and axial electric field, but it can reach about 1.19 kV/m. Radial magnetic field is the smallest one compared with other components, it reaches to maximum value at the position near to anode, it can influence arc characteristics.

  18. Steady-State Axial Temperature and Flow Velocity in Triga Channel.

    Energy Science and Technology Software Center (OSTI)

    2007-02-28

    Version 00 TRISTAN-IJS is a computer program for calculating steady-state axial temperature distribution and flow velocity through a vertical coolant channel in low power TRIGA reactor core, cooled by natural circulation. It is designed for steady-state thermohydraulic analysis of TRIGA research reactors operating at a low power level of 1-2 MW.

  19. The ultraviolet photodissociation of axial and equatorial conformers of 3-pyrroline

    SciTech Connect (OSTI)

    Oliver, Thomas A. A.; King, Graeme A.; Ashfold, Michael N. R.

    2010-11-21

    Resolved sets of photoproducts arising from the photodissociation of axial and equatorial conformers of 3-pyrroline have been observed using H(Rydberg) atom photofragment translational spectroscopy following excitation in the wavelength range of 250-213 nm. 3-pyrroline (alternatively 2,5-dihydropyrrole) is a five membered partially saturated heterocycle in which the bonding around the N atom is pyramidal (sp{sup 3} hybridized) and the N-H bond can lie either axial or equatorial to the ring. Careful analysis of total kinetic energy release data derived from H atom time-of-flight measurements reveals excitation of the 3-pyrrolinyl cofragment consistent with N-H bond fission in both the axial and equatorial conformers. This allows determination of the energy difference between the ground state conformers to be 340{+-}50 cm{sup -1} and the N-H bond strength for axial and equatorial conformers as 31 610{+-}50 and 31 270{+-}50 cm{sup -1}, respectively.

  20. Reporting central tendencies of chamber measured surface emission and oxidation

    SciTech Connect (OSTI)

    Abichou, Tarek; Clark, Jeremy; Chanton, Jeffery

    2011-05-15

    Methane emissions, concentrations, and oxidation were measured on eleven MSW landfills in eleven states spanning from California to Pennsylvania during the three year study. The flux measurements were performed using a static chamber technique. Initial concentration samples were collected immediately after placement of the flux chamber. Oxidation of the emitted methane was evaluated using stable isotope techniques. When reporting overall surface emissions and percent oxidation for a landfill cover, central tendencies are typically used to report 'averages' of the collected data. The objective of this study was to determine the best way to determine and report central tendencies. Results showed that 89% of the data sets of collected surface flux have lognormal distributions, 83% of the surface concentration data sets are also lognormal. Sixty seven percent (67%) of the isotope measured percent oxidation data sets are normally distributed. The distribution of data for all eleven landfills provides insight of the central tendencies of emissions, concentrations, and percent oxidation. When reporting the 'average' measurement for both flux and concentration data collected at the surface of a landfill, statistical analyses provided insight supporting the use of the geometric mean. But the arithmetic mean can accurately represent the percent oxidation, as measured with the stable isotope technique. We examined correlations between surface CH{sub 4} emissions and surface air CH{sub 4} concentrations. Correlation of the concentration and flux values using the geometric mean proved to be a good fit (R{sup 2} = 0.86), indicating that surface scans are a good way of identifying locations of high emissions.

  1. Pressure Loads by Gas in an Enclosed Chamber in DYNA3D

    SciTech Connect (OSTI)

    Lin, J; Badders, D C

    2002-08-08

    New algorithms that efficiently calculate the volume of a closed chamber are presented in this paper. The current pressure in the enclosed chamber can then be computed, based on the user-specified gas law, from the updated volume and the initial volume and pressure of the chamber. This pressure load function is very useful in modeling common features, such as air pocket, airbag, piston, and gun barrel, in structural analyses.

  2. Free surface modeling in OWC chamber with parabolic side walls using 3D BEM

    SciTech Connect (OSTI)

    Hasanabad, Madjid Ghodsi

    2015-03-10

    In this paper, BEM was used for free surface modeling in OWC chamber and out of it. Linear kinematic and dynamic boundary conditions were used for free surface out of OWC chamber and nonlinear forms were used for free surface in the chamber. These boundary conditions were discretized by finite differences method. Also, some thermodynamics relations were applied for trapped air behavior modeling in OWC chamber. Wave specifications in Chabahar region were used in modeling because these waves have an acceptable power for electricity generation. The results show a good agreement with results of other researches.

  3. The American Chamber of Commerce of Trinidad & Tobago | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Chamber of Commerce of Trinidad & Tobago The American Chamber of Commerce of Trinidad & Tobago May 13, 2008 - 12:00pm Addthis Remarks As Prepared for Delivery by Secretary Bodman Thank you, Raymond. I appreciate the Chamber organizing this gathering this morning. The American Chamber here on Trinidad and Tobago is an important regional voice in support of the free market, so I want to commend you for hosting the Business Future of the Americas conference next month. Having

  4. 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

    2014-03-04

    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.

  5. Effective point of measurement of thimble ion chambers in megavoltage photon beams

    SciTech Connect (OSTI)

    Tessier, Frederic; Kawrakow, Iwan

    2010-01-15

    Purpose: Determine the effective point of measurement (EPOM) of 12 thimble ion chambers, including miniature chambers and three models widely used for clinical reference dosimetry. The EPOM is the point at which the measured dose would arise in the measurement medium in the absence of the probe: For cylindrical chambers, it is shifted upstream relative to the central axis of the chamber. Although current dosimetry protocols prescribe a blanket upstream EPOM shift of 0.6r, with r as the chamber cavity radius, it has been shown in recent years that the EPOM does, in fact, depend on every detail of the chamber design and on the beam characteristics. In the wake of this finding, the authors undertake a comprehensive study of the EPOM for a series of chambers in water. Methods: This work relies on EGSnrc Monte Carlo calculations for the central axis depth dose in a water phantom and in ion chambers. They use a full Elekta Precise linac treatment head simulation to generate realistic photon beams with nominal energies of 6 and 25 MV and fields sizes of 10x10 and 40x40 cm{sup 2}. The correct EPOM shift for the 12 ion chambers, modeled in realistic detail, is taken as the one minimizing the deviation of the ratio between the dose to water and the dose to the gas of the chamber cavity, according to a method proposed and validated in previous work. Results: The analysis reveals that the actual EPOM shift is significantly smaller than the recommended value in current dosimetry protocols, by up to 25% for reference-class chambers and 80% for miniature chambers. The location of the EPOM also depends on the characteristics of the incident beam and varies in a well-defined way with the cavity length, the central electrode radius, and the thimble wall thickness. Conclusions: The authors confirm that an upstream EPOM shift of 0.6r is too large for thimble ion chambers in high energy photon beams. Proper values for the EPOM shift could be tabulated per beam and per chamber, but they

  6. U.S. Chamber of Commerce Biofuels Dialogue Series: Outlook for...

    Office of Environmental Management (EM)

    Commerce Biofuels Dialogue Series: Outlook for an Emerging Global Biofuels Market U.S. Chamber of Commerce Biofuels Dialogue Series: Outlook for an Emerging Global Biofuels Market ...

  7. Axial blanket fuel design and demonstration. First semi-annual progress report, January-September 1980. [PWR

    SciTech Connect (OSTI)

    Not Available

    1980-11-01

    The axial blanket fuel design in this program, which is retrofittable in operating pressurized water reactors, involves replacing the top and bottom of the enriched fuel column with low-enriched (less than or equal to 1.0 wt % /sup 235/U) fertile uranium. This repositioning of the fissile inventory in the fuel rod leads to decreased axial leakage and increased discharge burnups in the enriched fuel. Various axial blanket fuel designs, with blanket thicknesses from 0 to 10 inches and blanket enrichments from 0.2 to 1.0 wt % /sup 235/U, were investigated to determine the relationship between uranium utilization and power peaking. Analyses were preformed to assess the nuclear, mechanical, and thermal-hydraulic effects arising from the use of axial blankets. Four axial blanket lead test assemblies are being fabricated for scheduled irradiation in cycle 5 of Sacramento Municipal Utility District's Rancho Seco pressurized water reactor. Analyses to support licensing cycle 5 are in progress.

  8. The Effects of Heterogeneity in Magma Water Concentration on the Development of Flow Banding and Spherulites in Rhyolitic Lava

    SciTech Connect (OSTI)

    Seaman, S.; Dyar, D; Marinkovic, N

    2009-01-01

    This study focuses on the origin of flow-banded rhyolites that consist of compositionally similar darker and lighter flow bands of contrasting texture and color. Infrared radiation was used to obtain Fourier transform infrared (FTIR) spectra from which water concentrations were calculated, and to map variations in water concentrations across zones of spherulites and glass from the 23 million year old Sycamore Canyon lava flow of southern Arizona. Lighter-colored, thicker flow bands consist of gray glass, fine-grained quartz, and large (1.0 to 1.5 mm) spherulites. Darker-colored, thinner flow bands consist of orange glass and smaller (0.1 to 0.2 mm) spherulites. The centers of both large and small spherulites are occupied by either (1) a quartz or sanidine crystal, (2) a granophyric intergrowth, or (3) a vesicle. Mapping of water concentration (dominantly OH- in glass and OH- and H2O in sanidine crystals) illustrates fluctuating water availability during quenching of the host melt. Textures of large spherulites in the lighter (gray) bands in some cases indicate complex quenching histories that suggest that local water concentration controlled the generation of glass versus crystals. Small spherulites in darker (orange) bands have only one generation of radiating crystal growth. Both the glass surrounding spherulites, and the crystals in the spherulites contain more water in the gray flow bands than in the orange flow bands. Flow banding in the Sycamore Canyon lava flow may have originated by the stretching of a magma that contained pre-existing zones (vesicles or proto-vesicles) of contrasting water concentration, as the magma flowed in the conduit and on the surface. Variation in the original water concentration in the alternating layers is interpreted to have resulted in differences in undercooling textures in spherulites in the lighter compared to the darker flow bands.

  9. 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.

    2004-09-21

    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.

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

    SciTech Connect (OSTI)

    Latkowski, J F; Kramer, K J; Abbott, R P; Morris, K R; DeMuth, J; Divol, L; El-Dasher, B; Lafuente, A; Loosmore, G; Reyes, S; Moses, G A; Fratoni, M; Flowers, D; Aceves, S; Rhodes, M; Kane, J; Scott, H; Kramer, R; Pantano, C; Scullard, C; Sawicki, R; Wilks, S; Mehl, M

    2010-12-07

    The Laser Inertial Fusion Energy (LIFE) concept is being designed to operate as either a pure fusion or hybrid fusion-fission system. A key component of a LIFE engine is the fusion chamber subsystem. The present work details the chamber design for the pure fusion option. The fusion chamber consists of the first wall and blanket. This integrated system 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 LIFE design that meets all of these requirements is described herein.

  11. Fluid intensifier having a double acting power chamber with interconnected signal rods

    DOE Patents [OSTI]

    Whitehead, John C.

    2001-01-01

    A fluid driven reciprocating apparatus having a double acting power chamber with signal rods serving as high pressure pistons, or to transmit mechanical power. The signal rods are connected to a double acting piston in the power chamber thereby eliminating the need for pilot valves, with the piston being controlled by a pair of intake-exhaust valves. The signal rod includes two spaced seals along its length with a vented space therebetween so that the driving fluid and driven fluid can't mix, and performs a switching function to eliminate separate pilot valves. The intake-exhaust valves can be integrated into a single housing with the power chamber, or these valves can be built into the cylinder head only of the power chamber, or they can be separate from the power chamber.

  12. Method for imparting resistance to axial displacement of convolutions in a convoluted catalyst substrate

    SciTech Connect (OSTI)

    Pignon, T.E.

    1984-02-21

    A method for imparting resistance to axial displacement of convolutions in a convoluted substrate of the type comprising spirally wound superimposed plain and corrugated strips of metal which are suitable for use in supporting a catalyst in a catalyst unit in which the substrate is washcoated with a layer of refractory metal oxide and is useful for the purification of exhaust gases, especially exhaust gases from a motor vehicle. The method comprises making one or more weld runs across an end face of the substrate so as to weld together the plain and corrugated strips at points where they are contiguous. Even though only a minority of such points of contiguity are welded, the substrate becomes adequately resistant to axial displacing forces generated by exhaust gases passing through the substrate. The substrate may be washcoated prior to making the weld runs.

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

    SciTech Connect (OSTI)

    Oikawa, Kohei Saito, Yuta; Komizunai, Shota; Takahashi, Kazunori; Ando, Akira

    2014-02-15

    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.

  14. Measurement of the three-dimensional tip region flow field in an axial compressor

    SciTech Connect (OSTI)

    Stauter, R.C. )

    1993-07-01

    A two-color, five-beam LDV system has been configured to make simultaneous three-component velocity measurements of the flow field in a two-stage axial compressor model. The system has been used to make time-resolved measurements both between compressor blade rows and within the rotating blade passages in an axial compressor. The data show the nature and behavior of the complex, three-dimensional flow phenomena present in the tip region of a compressor as the convect downstream. In particular, the nature of the tip leakage vortex is apparent, being manifested by high blockage as well as the expected vortical motion. The data indicate that the radial flows associated with the tip leakage vortex begin to decrease while within the rotor passage, and that they temporarily increase aft of the passage.

  15. An analysis of axial compressor fouling and a blade cleaning method

    SciTech Connect (OSTI)

    Tarabrin, A.P.; Schurovsky, V.A.; Bodrov, A.I.; Stalder, J.P.

    1998-04-01

    The paper describes the phenomenon of axial compressor fouling due to aerosols contained in the air. Key parameters having effect on the level of fouling are determined. A mathematical model of a progressive compressor fouling using the stage-by-stage calculation method is developed. Calculation results on the influence of fouling on the compressor performance are presented. A new index of sensitivity of axial compressors to fouling is suggested. The paper gives information about Turbotect`s deposit cleaning method of compressor blading and the results of its application on an operating industrial gas turbine. Regular on-line and off-line washings of the compressor flow path made it possible to maintain a high level of engine efficiency and output.

  16. Integrated axial and tangential serpentine cooling circuit in a turbine airfoil

    DOE Patents [OSTI]

    Lee, Ching-Pang; Jiang, Nan; Marra, John J; Rudolph, Ronald J; Dalton, John P

    2015-05-05

    A continuous serpentine cooling circuit forming a progression of radial passages (44, 45, 46, 47A, 48A) between pressure and suction side walls (52, 54) in a MID region of a turbine airfoil (24). The circuit progresses first axially, then tangentially, ending in a last radial passage (48A) adjacent to the suction side (54) and not adjacent to the pressure side (52). The passages of the axial progression (44, 45, 46) may be adjacent to both the pressure and suction side walls of the airfoil. The next to last radial passage (47A) may be adjacent to the pressure side wall and not adjacent to the suction side wall. The last two radial passages (47A, 48A) may be longer along the pressure and suction side walls respectively than they are in a width direction, providing increased direct cooling surface area on the interiors of these hot walls.

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

    SciTech Connect (OSTI)

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

    2012-04-06

    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.

  18. Electrodynamics of a rotating body; Relativistic theory of circular and axial birefringence

    SciTech Connect (OSTI)

    Evans, M.W. . Dept. of Physics)

    1992-09-20

    In this paper, the theory of the electrodynamics of a rotating body is used to show that there exists: circular birefringence purely relativistic origin, composed of dispersive aether drag and residual, ensemble averaged, magnetization; non-relativistic circular birefringence due to the angular velocity of the body in the observer frame; non-relativistic axial birefringence in chiral media due to the angular velocity of the body; second order, relativistic equivalents.

  19. Rotor whirl forces induced by the tip clearance effect in axial flow compressors

    SciTech Connect (OSTI)

    Ehrich, F. )

    1993-10-01

    It is now widely recognized that destabilizing forces, tending to generate forward rotor whirl, are generated in axial flow turbines as a result of the nonuniform torque induced by the nonuniform tip-clearance in a deflected rotor--the so called Thomas/Alford force. It is also recognized that there will be a similar effect in axial flow compressors, but qualitative considerations cannot definitively establish the magnitude or even the direction of the induced whirling forces--that is, if they will tend to forward or backward whirl. Applying a parallel compressor model to simulate the operation of a compressor rotor deflected radially in its clearance, it is possible to derive a quantitative estimate of the proportionality factor [beta] which relates the Thomas/Alford force in axial flow compressors (i.e., the tangential force generated by a radial deflection of the rotor) to the torque level in the compressor. The analysis makes use of experimental data from the GE Aircraft Engines Low Speed Research Compressor facility comparing the performance of three different axial flow compressors, each with four stages (typical of a mid-block of an aircraft gas turbine compressor) at two different clearances. It is found that the value of [beta] is in the range of +0.27 to [minus]0.71 in the vicinity of the stages' nominal operating line and +0.08 to [minus]1.25 in the vicinity of the stages' operation at peak efficiency. The value of [beta] reaches a level of between [minus]1.16 and [minus]3.36 as the compressor is operated near its stalled condition.

  20. Fe XII STALKS AND THE ORIGIN OF THE AXIAL FIELD IN FILAMENT CHANNELS

    SciTech Connect (OSTI)

    Wang, Y.-M.; Sheeley, N. R. Jr.; Stenborg, G. E-mail: neil.sheeley@nrl.navy.mil

    2013-06-10

    Employing Fe XII images and line-of-sight magnetograms, we deduce the direction of the axial field in high-latitude filament channels from the orientation of the adjacent stalklike structures. Throughout the rising phase of the current solar cycle 24, filament channels poleward of latitude 30 Degree-Sign overwhelmingly obeyed the hemispheric chirality rule, being dextral (sinistral) in the northern (southern) hemisphere, corresponding to negative (positive) helicity. During the deep minimum of 2007-2009, the orientation of the Fe XII stalks was often difficult to determine, but no obvious violations of the rule were found. Although the hemispheric trend was still present during the maximum and early declining phase of cycle 23 (2000-2003), several high-latitude exceptions were identified at that time. From the observation that dextral (sinistral) filament channels form through the decay of active regions whose Fe XII features show a counterclockwise (clockwise) whorl, we conclude that the axial field direction is determined by the intrinsic helicity of the active regions. In contrast, generation of the axial field component by the photospheric differential rotation is difficult to reconcile with the observed chirality of polar crown and circular filament channels, and with the presence of filament channels along the equator. The main role of differential rotation in filament channel formation is to expedite the cancellation of flux and thus the removal of the transverse field component. We propose further that, rather than being ejected into the heliosphere, the axial field is eventually resubmerged by flux cancellation as the adjacent unipolar regions become increasingly mixed.

  1. Design of a Modular E-Core Flux Concentrating Axial Flux Machine: Preprint

    SciTech Connect (OSTI)

    Husain, Tausif; Sozer, Yilmaz; Husain, Iqbal; Muljadi, Eduard

    2015-08-24

    In this paper a novel E-Core axial flux machine is proposed. The machine has a double-stator, single-rotor configuration with flux-concentrating ferrite magnets and pole windings across each leg of an E-Core stator. E-Core stators with the proposed flux-concentrating rotor arrangement result in better magnet utilization and higher torque density. The machine also has a modular structure facilitating simpler construction. This paper presents a single-phase and a three-phase version of the E-Core machine. Case studies for a 1.1-kW, 400-rpm machine for both the single-phase and three-phase axial flux machines are presented. The results are verified through 3D finite element analysis. facilitating simpler construction. This paper presents a single-phase and a three-phase version of the E-Core machine. Case studies for a 1.1-kW, 400-rpm machine for both the single-phase and three-phase axial flux machines are presented. The results are verified through 3D finite element analysis.

  2. 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

    2014-01-01

    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.

  3. Dynamic control of rotating stall in axial flow compressors using aeromechanical feedback

    SciTech Connect (OSTI)

    Gysling, D.L.; Greitzer, E.M.

    1995-07-01

    Dynamic control of rotating stall in an axial flow compressor has been implemented using aeromechanical feedback. The control strategy developed used an array of wall jets, upstream of a single-stage compressor, which were regulated by locally reacting reed valves. These reed valves responded to the small-amplitude flow-field pressure perturbations that precede rotating stall. The valve design was such that the combined system, compressor plus reed valve controller, was stable under operating conditions that had been unstable without feedback. A 10 percent decrease in the stalling flow coefficient was obtained using the control strategy, and the extension of stall flow range was achieved with no measurable change in the steady-state performance of the compression system. The experiments demonstrate the first use of aeromechanical feedback to extend the stable operating range of an axial flow compressor, and the first use of local feedback and dynamic compensation techniques to suppress rotating stall. The design of the experiment was based on a two-dimensional stall inception model, which incorporated the effect of the aeromechanical feedback. The physical mechanism for rotating stall in axial flow compressors was examined with focus on the role of dynamic feedback in stabilizing compression system instability. As predicted and experimentally demonstrated, the effectiveness of the aeromechanical control strategy depends on a set of nondimensional control parameters that determine the interaction of the control strategy and the rotating stall dynamics.

  4. Characterization of a multi-axis ion chamber array

    SciTech Connect (OSTI)

    Simon, Thomas A.; Kozelka, Jakub; Simon, William E.; Kahler, Darren; Li, Jonathan; Liu, Chihray

    2010-11-15

    Purpose: The aim of this work was to characterize a multi-axis ion chamber array (IC PROFILER; Sun Nuclear Corporation, Melbourne, FL USA) that has the potential to simplify the acquisition of LINAC beam data. Methods: The IC PROFILER (or panel) measurement response was characterized with respect to radiation beam properties, including dose, dose per pulse, pulse rate frequency (PRF), and energy. Panel properties were also studied, including detector-calibration stability, power-on time, backscatter dependence, and the panel's agreement with water tank measurements [profiles, fractional depth dose (FDD), and output factors]. Results: The panel's relative deviation was typically within ({+-}) 1% of an independent (or nominal) response for all properties that were tested. Notable results were (a) a detectable relative field shape change of {approx}1% with linear accelerator PRF changes; (b) a large range in backscatter thickness had a minimal effect on the measured dose distribution (typically less than 1%); (c) the error spread in profile comparison between the panel and scanning water tank (Blue Phantom, CC13; IBA Schwarzenbruck, DE) was approximately ({+-}) 0.75%. Conclusions: The ability of the panel to accurately reproduce water tank profiles, FDDs, and output factors is an indication of its abilities as a dosimetry system. The benefits of using the panel versus a scanning water tank are less setup time and less error susceptibility. The same measurements (including device setup and breakdown) for both systems took 180 min with the water tank versus 30 min with the panel. The time-savings increase as the measurement load is increased.

  5. An open-walled ionization chamber appropriate to tritium monitoring for glovebox

    SciTech Connect (OSTI)

    Chen Zhilin; Chang Ruiming; Mu Long; Song Guoyang; Wang Heyi; Wu Guanyin; Wei Xiye

    2010-07-15

    An open-walled ionization chamber is developed to monitor the tritium concentration in gloveboxes in tritium processing systems. Two open walls are used to replace the sealed wall in common ionization chambers, through which the tritium gas can diffuse into the chamber without the aid of pumps and pipelines. Some basic properties of the chamber are examined to evaluate its performance. Results turn out that an open-walled chamber of 1 l in volume shows a considerably flat plateau over 700 V for a range of tritium concentration. The chamber also gives a good linear response to gamma fields over 4 decades under a pressure condition of 1 atm. The pressure dependence characteristics show that the ionization current is only sensitive at low pressures. The pressure influence becomes weaker as the pressure increases mainly due to the decrease in the mean free path of {beta} particles produced by tritium decay. The minimum detection limit of the chamber is 3.7x10{sup 5} Bq/m{sup 3}.

  6. Tests of a single-wire drift chamber for possible use in low intensity beams

    SciTech Connect (OSTI)

    Haggerty, H.

    1986-02-01

    A single cell drift chamber with two dimensional readout has been evaluated as a candidate for reliable and inexpensive momentum tagging of low intensity calibration beams. Charges induced on shaped cathode pads allow a measurement of the coordinate parallel to the wire, while the drift time allows a measurement of the coordinate perpendicular to the wire. Two chamber orientations were used during the tests. In one the chambers were arranged with their wires parallel. In this case the intrinsic resolution of the chambers was measured; the top and bottom cells were used to define a track coordinate and this was compared to the coordinate in the middle chamber. To see if either of the two coordinate measurements is linear in real space, the chambers were rearranged to the second orientation, with the middle chamber rotated 90/sup 0/. The drift time was plotted against the charge ratio. The conclusion drawn from this study is that while the drift time measurement has adequate resolution, the charge ratio measurement is not a viable option for beam line use. (LEW)

  7. Code System for Calculating the Radial and Axial Neutron Diffusion Coefficients in One-Group and Multigroup Theory.

    Energy Science and Technology Software Center (OSTI)

    1985-10-10

    MARCOPOLO calculates the radial and axial diffusion coefficients in one-group and multi-group theory for a cylinderized cell (Wigner-Seitz theory) with several concentric zones according to the isotropic shock or linear anisotropic shock hypotheses.

  8. Cost comparisons among free-air CO{sub 2} enrichment, open-top chamber, and sunlit controlled-environment chamber methods of CO{sub 2} exposure

    SciTech Connect (OSTI)

    Kimball, B.A.

    1992-12-31

    Several techniques for exposing plants and ecosystems to elevated CO{sub 2} were presented and the experimental characteristics of each were discussed in detail. However, one important factor which was not addressed is cost, which can easily dictate use of less than ideal methods. The purpose of this chapter is to evaluate and compare the approximate costs of the free-air CO{sub 2} enrichment (FACE) method with two other popular techniques - open-top chambers (OTC) and sunlit controlled-environment chambers (Soil, Plant, Atmosphere Research chambers, SPAR). The primary comparison among the SPAR, OTC, and FACE techniques is a consideration of the relative costs incurred in the production of high-CO{sub 2}-grown plants. However, measurements of plant response must also be made, which requires scientific personnel and instruments, so the plant production costs will also be compared to the overall costs of conducting CO{sub 2}-enrichment experiments. 2 refs., 1 fig., 1 tab.

  9. APS storage ring vacuum chamber tests for dimensional stability after bakeout cycling while under vacuum

    SciTech Connect (OSTI)

    Wehrle, R.; Nielsen, R.

    1990-09-01

    Vacuum chamber sections No. 1 and No. 2 were used for these tests. Section No. 1, a short straight section, is representative in these tests of Sections No. 3 and No. 5 as well. Section No. 2 is the longer curved section used within the dipole bend magnets and is representative of the similar Section No. 4. The combination of Sections No. 1 and No. 2 joined by a connected bellows was mounted as presently planned for the final installation. This afforded an early testing of chamber positional stability after bakeout cycling. Tests of chamber dimensional stability were also made during vacuum cycling.

  10. High Accuracy, Two-Dimensional Read-Out in Multiwire Proportional Chambers

    DOE R&D Accomplishments [OSTI]

    Charpak, G.; Sauli, F.

    1973-02-14

    In most applications of proportional chambers, especially in high-energy physics, separate chambers are used for measuring different coordinates. In general one coordinate is obtained by recording the pulses from the anode wires around which avalanches have grown. Several methods have been imagined for obtaining the position of an avalanche along a wire. In this article a method is proposed which leads to the same range of accuracies and may be preferred in some cases. The problem of accurate measurements for large-size chamber is also discussed.