Powered by Deep Web Technologies
Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

{sup 226}Ra and {sup 231}Pa systematics of axial MORB, crustal residence ages, and magma chamber characteristics at 9--10{degree}N East Pacific Rise  

SciTech Connect (OSTI)

Mass spectrometric measurements of {sup 30}Th-22{sup 226}Ra and {sup 235}-U{sup 231}Pa disequilibria for axial basalts are used to determine crustal residence ages for MORB magma and investigate the temporal and spatial characteristics of axial magma chambers (AMC) at 9--10{degrees}N East Pacific Rise (EPR). Relative crustal residence ages can be calculated from variations in {sup 226}Ra/{sup 230}Th and {sup 231}Pa/{sup 235}U activity ratios for axial lavas, if (1) mantle sources and melting are uniform, and mantle transfer times are constant or rapid for axial N-MORB, and (2) {sup 231}Pa/{sup 235}U and {sup 226}Ra/{sup 230}Th in the melt are unaffected by shallow level fractional crystallization. Uniform Th, Sr, and Nd isotopic systematics and incompatible element ratios for N-MORB along the 9--10{degrees}N segment indicate that mantle sources and transfer times are similar. In addition, estimated bulk solid/melt partition coefficients for U, Th, and Pa are small, hence effects of fractional crystallization on {sup 231}Pa/{sup 235}U ratios for the melt are expected to be negligible. However, fractional crystallization of plagioclase in the AMC would lower {sup 226}Ra/{sup 230}Th ratios in the melt and produce a positive bias in {sup 226}Ra crustal residence ages for fractionated lavas.

Goldstein, S.J.; Murrell, M.T. [Los Alamos National Lab., NM (United States); Perfit, M.R. [Univ., of Florida, Gainesville, FL (United States). Dept. of Geology; Batiza, R. [Univ., of Hawaii, Honolulu, HI (United States); Fornari, D.J. [Woods Hole Oceanographic Institution, MA (United States). Dept. of Geology and Geophysics

1994-06-01T23:59:59.000Z

2

E-Print Network 3.0 - axial tomography suggestive Sample Search...  

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

One aspect of the tomography assessment problem is to identify areas where the data suggest... into New Axial Volcano Magma Chamber Model, 100102-093005; 163,658; 2...

3

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

SciTech Connect (OSTI)

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

Peppin, W.A.

1986-02-10T23:59:59.000Z

4

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

SciTech Connect (OSTI)

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.

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

2004-01-01T23:59:59.000Z

5

The deep structure of Axial Volcano Michael West  

E-Print Network [OSTI]

available on Web #12;The deep structure of Axial Volcano IV. Magma Reservoir beneath Axial Volcano AxialThe deep structure of Axial Volcano Michael West Thesis defense, June 4, 2001 #12;Motivation What at Axial may be interpreted (NeMO, Neptune) #12;The deep structure of Axial Volcano IV. Magma Reservoir

West, Michael

6

Magma energy  

SciTech Connect (OSTI)

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

Dunn, J.C.

1987-01-01T23:59:59.000Z

7

Magma chamber processes at Mutnovsky Volcano, Russia.  

E-Print Network [OSTI]

??This dissertation is composed of two manuscripts about the evolution of Mutnovsky Volcano in Kamchatka, Russia. Mutnovsky has been active for the past approximately 80,000… (more)

Robertson, Kelly L.

2011-01-01T23:59:59.000Z

8

Flow chamber  

DOE Patents [OSTI]

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.

Morozov, Victor (Manassas, VA)

2011-01-18T23:59:59.000Z

9

Magma energy: a feasible alternative  

SciTech Connect (OSTI)

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

Colp, J.L.

1980-03-01T23:59:59.000Z

10

Co-axial, high energy gamma generator  

DOE Patents [OSTI]

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.

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

2011-08-16T23:59:59.000Z

11

Role of oxidized, S-rich mafic magmas for giant Cu mineralization: Evidence from Pinatubo, Bingham Canyon and El Teniente  

E-Print Network [OSTI]

dacitic magma chamber (~ 800/C), then acid-sulphatehydrothermal fluids. At Bingham Canyon, UtahRole of oxidized, S-rich mafic magmas for giant Cu mineralization: Evidence from Pinatubo, Bingham Canyon and El Teniente Hattori, K.H. and De Hoog, J.C.M., Earth Sciences, Univ. Ottawa, Ottawa, K1N 6N5

12

Cyclone reactor with internal separation and axial recirculation  

DOE Patents [OSTI]

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.

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

1989-01-01T23:59:59.000Z

13

Magma energy: engineering feasibility of energy extraction from magma bodies  

SciTech Connect (OSTI)

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

Traeger, R.K.

1983-12-01T23:59:59.000Z

14

Cyclone reactor with internal separation and axial recirculation  

DOE Patents [OSTI]

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.

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

1988-07-19T23:59:59.000Z

15

Performance of An Axial Gas Ionization Detector  

E-Print Network [OSTI]

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

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

2006-10-11T23:59:59.000Z

16

Ionization chamber  

DOE Patents [OSTI]

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.

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

1981-01-01T23:59:59.000Z

17

Chamber transport  

SciTech Connect (OSTI)

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.

OLSON,CRAIG L.

2000-05-17T23:59:59.000Z

18

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

E-Print Network [OSTI]

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

Biggs, Juliet

19

Magma Energy | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating Solar Powerstories on climateJunoMedanos EnergyM CommunicationsGDC PowerValleyMagma

20

Magma Energy Research Project, FY80 annual progress report  

SciTech Connect (OSTI)

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

Colp, J.L. (ed.)

1982-04-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Magma Flow through Elastic-Walled Dikes  

E-Print Network [OSTI]

Mountain · · · · · Yucca Mountain ~300 m ~200 m ~ 10 km ~ 1 m~ 3 km Repository tunnels Magma dike Magma.g., frozen dike Eppelsberg #12;Eiffel 2002 boccas? #12;Ship Rock U.S.A. #12;Proposed repository site at Yucca

Al Hanbali, Ahmad

22

Measuring axial pump thrust  

DOE Patents [OSTI]

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.

Suchoza, B.P.; Becse, I.

1988-11-08T23:59:59.000Z

23

Measuring axial pump thrust  

DOE Patents [OSTI]

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.

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

1988-01-01T23:59:59.000Z

24

Causes and consequences of unsteady crustal magma transport  

E-Print Network [OSTI]

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

Karlstrom, Leif

2011-01-01T23:59:59.000Z

25

Axial static mixer  

DOE Patents [OSTI]

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.

Sandrock, H.E.

1982-05-06T23:59:59.000Z

26

Final report - Magma Energy Research Project  

SciTech Connect (OSTI)

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

Colp, J.L.

1982-10-01T23:59:59.000Z

27

Two chamber reaction furnace  

DOE Patents [OSTI]

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.

Blaugher, Richard D. (Evergreen, CO)

1998-05-05T23:59:59.000Z

28

THERMODYNAMIC AND TRANSPORT PROPERTIES OF SILICATE MELTS AND MAGMA  

E-Print Network [OSTI]

PROPERTIES5 Density and Equation of State6 Enthalpy, Entropy and Heat Capacity7 VI. MAGMA TRANSPORT-1- THERMODYNAMIC AND TRANSPORT PROPERTIES OF SILICATE MELTS AND MAGMA Charles E. Lesher PROPERTIES8 Magma Rheology9 Thermal Conductivity: Radiative and Phonon10 Diffusion: Self, Tracer and Chemical

Spera, Frank J.

29

ORIGINAL PAPER Granite magma migration and emplacement along thrusts  

E-Print Network [OSTI]

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

Galland, Olivier

30

Mercury Chamber Considerations  

E-Print Network [OSTI]

Mercury Chamber Considerations V. Graves IDS-NF Target Studies July 2011 #12;2 Managed by UT-Battelle for the U.S. Department of Energy Mercury Chamber Considerations, July 2011 Flow Loop Review · 1 cm dia nozzle, 20 m/s jet requires 1.57 liter/sec mercury flow (94.2 liter/min, 24.9 gpm). · MERIT experiment

McDonald, Kirk

31

Sleeve reaction chamber system  

DOE Patents [OSTI]

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.

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

2009-08-25T23:59:59.000Z

32

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

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating SolarElectricEnergyCTBarreis aCallahanWindSyracuse,CER.pngGreatChateau Tebeau LLCOpen

33

Automated soil gas monitoring chamber  

DOE Patents [OSTI]

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.

Edwards, Nelson T.; Riggs, Jeffery S.

2003-07-29T23:59:59.000Z

34

Secondary emission gas chamber  

E-Print Network [OSTI]

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

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

2014-12-10T23:59:59.000Z

35

Liquid Wall Chambers  

SciTech Connect (OSTI)

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

Meier, W R

2011-02-24T23:59:59.000Z

36

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

SciTech Connect (OSTI)

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

Traeger, R.K.

1983-12-01T23:59:59.000Z

37

Vertical two chamber reaction furnace  

DOE Patents [OSTI]

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.

Blaugher, Richard D. (Evergreen, CO)

1999-03-16T23:59:59.000Z

38

A note on axial symmetries  

E-Print Network [OSTI]

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

Christopher Beetle; Shawn Wilder

2013-12-31T23:59:59.000Z

39

The four-chambered heart.  

E-Print Network [OSTI]

??The Four-Chambered Heart is a collection of four short stories centering around themes and motifs most popular in the genre of magical realism. Important to… (more)

Christie, Jennifer L.

2013-01-01T23:59:59.000Z

40

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

DOE Patents [OSTI]

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.

Reichner, P.; Dollard, W.J.

1991-01-08T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

MFE Chamber Overview Mohamed Abdou  

E-Print Network [OSTI]

MFE Chamber Overview Mohamed Abdou Presented to: Chamber Technology Peer Review UCLA, Los Angeles/Be/structure thermomechanics interactions - Framework: IEA collaboration; part of US strategy to gain access to the larger to VNS; sparked world interest - IEA initiated a study in 1994 on VNS, called HVPNS. A scholarly

Abdou, Mohamed

42

Ion chamber based neutron detectors  

DOE Patents [OSTI]

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.

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

2014-12-16T23:59:59.000Z

43

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

SciTech Connect (OSTI)

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

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

1980-02-01T23:59:59.000Z

44

E-Print Network 3.0 - arc magma genesis Sample Search Results  

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

of oxidized, S-rich mafic magmas for giant Cu mineralization: Evidence from Pinatubo, Bingham Canyon and El Teniente Summary: Role of oxidized, S-rich mafic magmas for giant Cu...

45

PWR AXIAL BURNUP PROFILE ANALYSIS  

SciTech Connect (OSTI)

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).

J.M. Acaglione

2003-09-17T23:59:59.000Z

46

Light diffusing fiber optic chamber  

DOE Patents [OSTI]

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.

Maitland, Duncan J. (Lafayette, CA)

2002-01-01T23:59:59.000Z

47

Magma to Microbe: Modeling Hydrothermal Processes at Ocean Spreading Centers  

E-Print Network [OSTI]

215 Magma to Microbe: Modeling Hydrothermal Processes at Ocean Spreading Centers Geophysical is very limited. Low-temperature diffuse vent fluids, ubiquitous at hydrothermal systems, provide one microorganisms from diffuse hydrothermal vent fluids and the subseafloor at basalt-hosted mid-ocean ridges

Holden, James F.

48

Magma to Microbe: Modeling Hydrothermal Processes at Ocean Spreading Centers  

E-Print Network [OSTI]

233 Magma to Microbe: Modeling Hydrothermal Processes at Ocean Spreading Centers Geophysical to mixing between #12;234 MIcrOBE MInErAl prOcESSES In SEAflOOr SulfIdES seawater and the hydrothermal of Washington, Seattle, Washington, USA Hydrothermal vent sulfides are diverse and dynamic habitats

Holden, James F.

49

ORIGINAL PAPER Assimilation and diffusion during xenolith-magma  

E-Print Network [OSTI]

(responsible for the linear mixing trends) and (2) diffusion-controlled redistribution of elements between bothORIGINAL PAPER Assimilation and diffusion during xenolith-magma interaction: a case study the assimilation of granitic melt. Linear mixing trends on Harker diagrams for most network-forming and mainly slow-diffusing

Podladchikov, Yuri

50

Axial cylinder internal combustion engine  

SciTech Connect (OSTI)

This patent describes improvement in a barrel type internal combustion engine including an engine block having axial-positioned cylinders with reciprocating pistons arranged in a circular pattern: a drive shaft concentrically positioned within the cylinder block having an offset portion extending outside the cylinder block; a wobble spider rotatably journaled to the offset portion; connecting rods for each cylinder connecting each piston to the wobble spider. The improvement comprising: a first sleeve bearing means supporting the drive shaft in the engine block in a cantilevered manner for radial loads; a second sleeve bearing means rotatably supporting the wobble spider on the offset portion of the drive shaft for radial loads; a first roller bearing means positioned between the offset portion of the drive shaft and the wobble spider carrying thrust loadings only; a second roller bearing means carrying thrust loads only reacting to the first roller bearing located on the opposite end of the driveshaft between the shaft and the engine block.

Gonzalez, C.

1992-03-10T23:59:59.000Z

51

Axial interaction free-electron laser  

DOE Patents [OSTI]

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.

Carlsten, B.E.

1997-09-02T23:59:59.000Z

52

A University of Alabama Axial-Gap Electric Motor Developmenty  

E-Print Network [OSTI]

CAVT A University of Alabama Axial-Gap Electric Motor Developmenty Research Center OBJECTIVE ­ Develop axial gap permanent-magnet electric Axial motor ­ Develop axial gap permanent-magnet electric motor topologies with high torque and power densities MOTIVATION ­ Axial-gap ("pancake") motors have

Carver, Jeffrey C.

53

Flow Split Venturi, Axially-Rotated Valve  

SciTech Connect (OSTI)

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.

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

2000-02-22T23:59:59.000Z

54

The TESLA Time Projection Chamber  

E-Print Network [OSTI]

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

Nabil Ghodbane

2002-12-12T23:59:59.000Z

55

VERTEX CHAMBERS TARGET CELL CALORIMETER  

E-Print Network [OSTI]

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

56

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

E-Print Network [OSTI]

G. , Detrick, R.S. , Sinton, J. , 2002. Crustal thicknessJ.P. , Detrick, R.S. , Sinton, J. , 2004. Constructing the3767-3787. Detrick, R.S. , Sinton, J.M. , Ito, G. , Canales,

Dingler, Allison Maria Jacobs

2007-01-01T23:59:59.000Z

57

Controlling Axial p-n Heterojunction Abruptness Through Catalyst...  

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

Axial p-n Heterojunction Abruptness Through Catalyst Alloying in Vapor-Liquid-Solid Grown Semiconductor Nanowires. Controlling Axial p-n Heterojunction Abruptness Through Catalyst...

58

Chamber dynamic research with pulsed power  

SciTech Connect (OSTI)

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

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

2000-05-15T23:59:59.000Z

59

Performance limits of axial turbomachine stages  

E-Print Network [OSTI]

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

Hall, David Kenneth

2011-01-01T23:59:59.000Z

60

Split Venturi, Axially-Rotated Valve  

DOE Patents [OSTI]

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.

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

2000-08-29T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Recent Advances in Chamber Science and Technology  

E-Print Network [OSTI]

Recent Advances in Chamber Science and Technology Mohamed Abdou April 8, 2002ISFNT-6 San Diego, USA #12;Recent Advances in Chamber Science & Technology OutlineOutline · Highlights of Major World - Experiments - Analysis & Design #12;Highlights of Major World Programs on Chamber (Blanket) Technology

Abdou, Mohamed

62

Mercury Chamber NF-IDS Meeting  

E-Print Network [OSTI]

-Battelle for the U.S. Department of Energy Mercury Chamber Update Oct 2011 Starting Point: Coil and Shielding Concept IDS120H #12;3 Managed by UT-Battelle for the U.S. Department of Energy Mercury Chamber Update Oct 2011 · Penetrations (ports) into chamber ­ Nozzle ­ Hg drains (overflow and maintenance) ­ Vents (in and out) ­ Beam

McDonald, Kirk

63

Megacrystals track magma convection between reservoir and surface  

E-Print Network [OSTI]

, persis- ntly emit prodigious quantities of gas and heat at the surface ithout significant accompanying lava flows or tephra production rancis et al., 1993). The decoupling of gas and thermal energy om the magma efflux has been investigated in several... , tungsten filament, operating voltage of 100 kV, fil- ament current of 80 ?A, and 2 s exposure time. Whole crystals (from 1 to 5 cm in length) were mounted on to carbon fibre rods using Araldite epoxy resin. The samples were rotated through 360? during...

Moussallam, Yves; Oppenheimer, Clive; Scaillet, Bruno; Buisman, Iris; Kimball, Christine; Dunbar, Nelia; Burgisser, Alain; Schipper, C.Ian; Andújar, Joan; Kyle, Philip

2015-01-13T23:59:59.000Z

64

2014 PMEL Lab Review FY2009 Journal Articles  

E-Print Network [OSTI]

.L. Bryden (2009): Estimating the storage of anthropogenic carbon in the subtropical): Relationships between hydrothermal activity and axial magma chamber distribution, depthGuire, P. Raymond, and C.J. Tucker (2009): Carbon cycle observations: Gaps threaten

65

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

E-Print Network [OSTI]

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

Giménez, Domingo

66

Direct numerical simulation of an iron rain in the magma ocean  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

67

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

E-Print Network [OSTI]

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

Boyer, Edmond

68

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

E-Print Network [OSTI]

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

Boyer, Edmond

69

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

DOE Patents [OSTI]

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).

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

1991-01-01T23:59:59.000Z

70

Rapid-quench axially staged combustor  

DOE Patents [OSTI]

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.

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

1999-01-01T23:59:59.000Z

71

Painleve Analysis and Similarity Reductions for the Magma Equation  

E-Print Network [OSTI]

In this paper, we examine a generalized magma equation for rational values of two parameters, $m$ and $n$. Firstly, the similarity reductions are found using the Lie group method of infinitesimal transformations. The Painlev\\'e ODE test is then applied to the travelling wave reduction, and the pairs of $m$ and $n$ which pass the test are identified. These particular pairs are further subjected to the ODE test on their other symmetry reductions. Only two cases remain which pass the ODE test for all such symmetry reductions and these are completely integrable. The case when $m=0$, $n=-1$ is related to the Hirota-Satsuma equation and for $m=\\tfrac12$, $n=-\\tfrac12$, it is a real, generalized, pumped Maxwell-Bloch equation.

Shirley E. Harris; Peter A. Clarkson

2006-10-05T23:59:59.000Z

72

Magma simulation facility design considerations, capabilities, and operational considerations  

SciTech Connect (OSTI)

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

Wemple, R.P.

1981-04-01T23:59:59.000Z

73

The Mark II Vertex Drift Chamber  

SciTech Connect (OSTI)

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

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

1989-03-01T23:59:59.000Z

74

Description of Axial Detail for ROK Fuel  

SciTech Connect (OSTI)

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

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

2012-04-20T23:59:59.000Z

75

Review of Axial Burnup Distribution Considerations for Burnup Credit Calculations  

SciTech Connect (OSTI)

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

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

2000-03-01T23:59:59.000Z

76

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

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

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

77

meters in CO2 euthanasia chambers. All CO2 euthanasia chambers in both  

E-Print Network [OSTI]

meters in CO2 euthanasia chambers. All CO2 euthanasia chambers in both the facilities and laboratories will need flow meters. ULAR is currently in the process of identifying a cost-effective, accurate, and durable flow meter to install in all of the CO2 chambers in all of the vivaria. When a specific model

Bushman, Frederic

78

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

E-Print Network [OSTI]

. As ITER serves as a fusion testing facility for magnetic fusion energy (MFE) nuclear technology componentIFE Chamber Technology Testing Program In NIF and Chamber Development Test Plan Mohamed A. Abdou chamber technology testing program in NIF involoving: criteria for evaluation

Abdou, Mohamed

79

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

SciTech Connect (OSTI)

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

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

1986-04-01T23:59:59.000Z

80

Piping inspection carriage having axially displaceable sensor  

DOE Patents [OSTI]

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.

Zollinger, William T. (Martinez, GA); Treanor, Richard C. (Augusta, GA)

1994-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Piping inspection carriage having axially displaceable sensor  

DOE Patents [OSTI]

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.

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

1994-12-06T23:59:59.000Z

82

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

SciTech Connect (OSTI)

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

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

2014-09-01T23:59:59.000Z

83

RESEARCH ARTICLE Magma at depth: a retrospective analysis of the 1975 unrest  

E-Print Network [OSTI]

the following three decades. The area of snow-free ground in the active crater has not returned to pre, USA. In: Moran SC, Newhall CG, Roman DC (eds) Failed eruptions: Late-stage cessation of magma ascent

84

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

SciTech Connect (OSTI)

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

Goldstein, N.E.; Flexser, S.

1984-12-01T23:59:59.000Z

85

Engineering design of a hypobaric plant growth chamber  

E-Print Network [OSTI]

plants with the chamber in place and removed. With the chamber removed, PAR levels were recorded as 461 []mol m?² s?¹; inside the complete chamber the level decreased to 408 []mol m?² s?¹, a difference of 11.5%....

Purswell, Joseph Lawrence

2002-01-01T23:59:59.000Z

86

Baroclinic tides in an axially symmetric basin  

E-Print Network [OSTI]

Energetics Returning to the governing equations (66) through (6&7) and multiplving (66) by phu?, (66) by phv?, and (67) by php?gives the result; phu?? f v?~ ? ~ ~ p S? m=O 0(, = phu?g h?o, c3 T f&hv?g o'j r SH (96) (96) aud ap? 1 a I au? I ~ ah.... Rowe (Head of Department) December 1989 ABSTRACT Baroclinic Tides in an Axially Symmetric Basin. (December 1989) Edward Paul Dever. B. S. , Texas Ag-XI University Chair ol' Advisory Committee: Prof. Robert 0. Reid A. coupled normal mode model...

Dever, Edward Paul

2012-06-07T23:59:59.000Z

87

Formation mechanisms of combustion chamber deposits  

E-Print Network [OSTI]

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

O'Brien, Christopher J. (Christopher John)

2001-01-01T23:59:59.000Z

88

Cloud chamber visualization of primary cosmic rays  

SciTech Connect (OSTI)

From 1948 until 1963, cloud chambers were carried to the top of the atmosphere by balloons. From these flights, which were begun by Edward P. Ney at the University of Minnesota, came the following results: discovery of heavy cosmic ray nuclei, development of scintillation and cherenkov detectors, discovery of cosmic ray electrons, and studies of solar proton events. The history of that era is illustrated here by cloud chamber photographs of primary cosmic rays.

Earl, James A. [Department of Astronomy, University of Maryland, College Park MD (United States)

2013-02-07T23:59:59.000Z

89

Study of casing treatment effects in axial flow compressors  

E-Print Network [OSTI]

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

Schiller, Robert Neil

1973-01-01T23:59:59.000Z

90

Final report for NIF chamber dynamics studies  

SciTech Connect (OSTI)

The National Ignition Facility (NIF), a 1.8 MJ, 192 laser beam facility, will have anticipated fusion yields of up to 20 MJ from D-T pellets encased in a gold hohlraum target. The energy emitted from the target in the form of x rays, neutrons, target debris kinetic energy, and target shrapnel will be contained in a 5 m. radius spherical target chamber. various diagnostics will be stationed around the target at varying distances from the target. During each shot, the target will emit x rays that will vaporize nearby target facing surfaces including those of the diagnostics, the target positioner, and other chamber structures. This ablated vapor will be transported throughout the chamber, and will eventually condense and deposit on surfaces in the chamber, including the final optics debris shields. The research at the University of California at Berkeley relates primarily to the NIF chamber dynamics. The key design issues are the ablation of the chamber structures, transport of the vapor through the chamber and the condensation or deposition processes of those vaporized materials. An understanding of these processes is essential in developing a concept for protecting the fina optics debris shields from an excessive coating (> 10 A) of target debris and ablated material, thereby prolonging their lifetime between change-outs. At Berkeley, we have studied the physical issues of the ablation process and the effects of varying materials, the condensation process of the vaporized material, and design schemes that can lower the threat posed to the debris shields by these processes. The work or portions of the work completed this year have been published in several papers and a dissertation [l-5].

Burnham, A; Peterson, P F; Scott, J M

1998-09-01T23:59:59.000Z

91

Magnetite-bubble aggregates at mixing interfaces in andesite magma bodies  

E-Print Network [OSTI]

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

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

2014-08-14T23:59:59.000Z

92

The Shaft Torque of a Tandem Axial-Piston Pump  

E-Print Network [OSTI]

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

Manring, Noah D.

93

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

E-Print Network [OSTI]

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

Solar, Gary S.

94

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

E-Print Network [OSTI]

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

Schmalzl, Jörg

95

Meson cloud contributions to baryon axial form factors  

E-Print Network [OSTI]

The axial form factor as well as the axial charge of octet baryons are studied in the perturbative chiral quark model (PCQM) with the quark wave functions predetermined by fitting the theoretical results of the proton charge form factor to experimental data. The theoretical results are found, based on the predetermined quark wave functions, in good agreement with experimental data and lattice values. This may indicate that the electric charge and axial charge distributions of the constituent quarks are the same. The study reveals that the meson cloud plays an important role in the axial charge of octet baryons, contributing 30%-40% to the total values, and strange sea quarks have a considerable contribution to the axial charge of the $\\Sigma$ and $\\Xi$.

X. Y. Liu; K. Khosonthongkee; A. Limphirat; P. Suebka; Y. Yan

2014-08-01T23:59:59.000Z

96

Lifetime tests for MAC vertex chamber  

SciTech Connect (OSTI)

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

Nelson, H.N.

1986-07-01T23:59:59.000Z

97

A Cosmic Ray Measurement Facility for ATLAS Muon Chambers  

E-Print Network [OSTI]

Monitored Drift Tube (MDT) chambers will constitute the large majority of precision detectors in the Muon Spectrometer of the ATLAS experiment at the Large Hadron Collider at CERN. For commissioning and calibration of MDT chambers, a Cosmic Ray Measurement Facility is in operation at Munich University. The objectives of this facility are to test the chambers and on-chamber electronics, to map the positions of the anode wires within the chambers with the precision needed for standalone muon momentum measurement in ATLAS, and to gain experience in the operation of the chambers and on-line calibration procedures. Until the start of muon chamber installation in ATLAS, 88 chambers built at the Max Planck Institute for Physics in Munich have to be commissioned and calibrated. With a data taking period of one day individual wire positions can be measured with an accuracy of 8.3 micrometers in the chamber plane and 27 micrometers in the direction perpendicular to that plane.

O. Biebel; M. Binder; M. Boutemeur; A. Brandt; J. Dubbert; G. Duckeck; J. Elmsheuser; F. Fiedler; R. Hertenberger; O. Kortner; T. Nunnemann; F. Rauscher; D. Schaile; P. Schieferdecker; A. Staude; W. Stiller; R. Stroehmer; R. Vertesi

2003-07-30T23:59:59.000Z

98

High Power Co-Axial SRF Coupler  

SciTech Connect (OSTI)

There are over 35 coupler designs for SRF cavities ranging in frequency from 325 to 1500 MHz. Two-thirds of these designs are coaxial couplers using disk or cylindrical ceramics in various combinations and configurations. While it is well known that dielectric losses go down by several orders of magnitude at cryogenic temperatures, it not well known that the thermal conductivity also goes down, and it is the ratio of thermal conductivity to loss tangent (SRF ceramic Quality Factor) and ceramic volume which will determine the heat load of any given design. We describe a novel robust co-axial SRF coupler design which uses compressed window technology. This technology will allow the use of highly thermally conductive materials for cryogenic windows. The mechanical designs will fit into standard-sized ConFlat® flanges for ease of assembly. Two windows will be used in a coaxial line. The distance between the windows is adjusted to cancel their reflections so that the same window can be used in many different applications at various frequencies.

M.L. Neubauer, R.A. Rimmer

2009-05-01T23:59:59.000Z

99

Pulsatory magma supply to a phonolite lava lake Clive Oppenheimer a,  

E-Print Network [OSTI]

Pulsatory magma supply to a phonolite lava lake Clive Oppenheimer a, , Alexandra S. Lomakina b processes (Tazieff, 1997; Oppenheimer et al., 2004). The decadal persistence of some lava lakes, with no net, though it may well have existed for a century or more (Oppenheimer and Kyle, 2008). Since 2001, the lake

Kingsbury, Nick

100

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

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

E-Print Network [OSTI]

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

Demouchy, Sylvie

102

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

SciTech Connect (OSTI)

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

Woodward, M H

1982-04-01T23:59:59.000Z

103

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

SciTech Connect (OSTI)

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

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

2011-10-10T23:59:59.000Z

104

On-Site Wastewater Treatment Systems: Leaching Chambers  

E-Print Network [OSTI]

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

Lesikar, Bruce J.

2000-02-04T23:59:59.000Z

105

E-Print Network 3.0 - axially loaded steel Sample Search Results  

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

Search Sample search results for: axially loaded steel Page: << < 1 2 3 4 5 > >> 1 Mechanical Engineering Department WORCESTER POLYTECHNIC INSTITUTE Summary: Department Axial...

106

E-Print Network 3.0 - axial kinetic energy Sample Search Results  

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

axial flow fan systems. Despite... -vortex-driven flow structures to increase the energy efficiency of axial flow fan systems to provide high quality... the mean kinetic...

107

E-Print Network 3.0 - axial symmetry Sample Search Results  

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

components. We also... --Analytical calculation, axial magnetization, magnetic field, permanent-magnet rings, radial magnetization. I... . The case of a magnet ring axially...

108

E-Print Network 3.0 - axially symmetric magnetic Sample Search...  

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

magnetic Search Powered by Explorit Topic List Advanced Search Sample search results for: axially symmetric magnetic Page: << < 1 2 3 4 5 > >> 1 Axial vs. equatorial dipolar dynamo...

109

E-Print Network 3.0 - axially symmetric solutions Sample Search...  

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

and Rayleigh numbers close to onset of convection. Axial dipole solutions are subcritical in all... - ble the Rayleigh number the solution switches to an axial dipole...

110

Reduce Steam Trap Failures at Chambers Works  

E-Print Network [OSTI]

Ultrasonic Inspection At least 2 times per year Steam Trap Surveyor Submit reports to area management, energy team, and reliability engineers for each area every month Steam Trap Team Leader Control Plan ? Process Owner agrees...Reduce Steam Trap Failures at Chambers Works GB/BB Name: Cyndi Kouba Mentor/MBB: Andrew Degraff Team Members Michael Crowley(Site Energy Lead), (Charlie) Flanigan (Aramids-maintenance), Ben Snyder (Aramids-ATO), Michael Scruggs (Central...

Kouba, C.

111

axial blanket experiments: Topics by E-print Network  

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

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

112

The axial behaviour of piled foundations in liquefiable soil  

E-Print Network [OSTI]

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

Stringer, Mark

2012-07-03T23:59:59.000Z

113

Applications of axial and radial compressor dynamic system modeling  

E-Print Network [OSTI]

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

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

2001-01-01T23:59:59.000Z

114

Optimization of the axial power shape in pressurized water reactors  

E-Print Network [OSTI]

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

Melik, M. A.

1981-01-01T23:59:59.000Z

115

Design of high temperature high speed electromagnetic axial thrust bearing  

E-Print Network [OSTI]

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

Mohiuddin, Mohammad Waqar

2002-01-01T23:59:59.000Z

116

A wave refraction analysis for an axially symmetrical island  

E-Print Network [OSTI]

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

Forst, Ronald John

1966-01-01T23:59:59.000Z

117

Superfluid Phase Stability of 3 He in Axially Anisotropic Aerogel  

E-Print Network [OSTI]

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

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

118

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

SciTech Connect (OSTI)

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

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

1995-12-31T23:59:59.000Z

119

Vacuum chamber with a supersonic-flow aerodynamic window  

DOE Patents [OSTI]

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.

Hanson, C.L.

1980-10-14T23:59:59.000Z

120

Vacuum chamber with a supersonic flow aerodynamic window  

DOE Patents [OSTI]

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.

Hanson, Clark L. (Livermore, CA)

1982-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

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

SciTech Connect (OSTI)

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

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

1986-01-01T23:59:59.000Z

122

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

SciTech Connect (OSTI)

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.

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

1988-04-01T23:59:59.000Z

123

E-Print Network 3.0 - axial piston pumps Sample Search Results  

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

pumps Search Powered by Explorit Topic List Advanced Search Sample search results for: axial piston pumps...

124

Vacuum chamber for containing particle beams  

DOE Patents [OSTI]

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.

Harvey, A.

1985-11-26T23:59:59.000Z

125

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

SciTech Connect (OSTI)

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

Hardee, H.C.

1980-09-01T23:59:59.000Z

126

Axial Current Generation from Electric Field: Chiral Electric Separation Effect  

E-Print Network [OSTI]

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

Xu-Guang Huang; Jinfeng Liao

2013-06-07T23:59:59.000Z

127

An investigation of axial-flow compressor blade treatments  

E-Print Network [OSTI]

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

Sangerhausen, Charles Roger

1974-01-01T23:59:59.000Z

128

Tests of a Novel Design of Resistive Plate Chambers  

E-Print Network [OSTI]

A novel design of Resistive Plate Chambers (RPCs), using only a single resistive plate, is being proposed. Based on this design, two large size prototype chambers were constructed and were tested with cosmic rays and in particle beams. The tests confirmed the viability of this new approach. In addition to showing an improved single-particle response compared to the traditional 2-plate design, the novel chambers also prove to be suitable for calorimetric applications.

Bilki, B; Freund, B; Neubüser, C; Onel, Y; Repond, J; Schlereth, J; Xia, L

2015-01-01T23:59:59.000Z

129

Bubble Chambers for Experiments in Nuclear Astrophysics  

E-Print Network [OSTI]

A bubble chamber has been developed to be used as an active target system for low energy nuclear astrophysics experiments. Adopting ideas from dark matter detection with superheated liquids, a detector system compatible with gamma-ray beams has been developed. This detector alleviates some of the limitations encountered in standard measurements of the minute cross sections of interest to stellar environments. While the astrophysically relevant nuclear reaction processes at hydrostatic burning temperatures are dominated by radiative captures, in this experimental scheme we measure the time-reversed processes. Such photodisintegrations allow us to compute the radiative capture cross sections when transitions to excited states of the reaction products are negligible. Due to the transformation of phase space, the photodisintegration cross sections are up to two orders of magnitude higher. The main advantage of the new target-detector system is a density several orders of magnitude higher than conventional gas tar...

DiGiovine, B; Holt, R J; Rehm, K E; Raut, R; Robinson, A; Sonnenschein, A; Rusev, G; Tonchev, A P; Ugalde, C

2015-01-01T23:59:59.000Z

130

The hydrogen bubble chamber and the strange resonances  

SciTech Connect (OSTI)

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

Alvarez, L.W.

1985-06-01T23:59:59.000Z

131

air wall ionization chambers: Topics by E-print Network  

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

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

132

Dielectric liquid ionization chambers for detecting fast neutrons  

E-Print Network [OSTI]

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

Boyd, Erin M

2008-01-01T23:59:59.000Z

133

Operational benefits of relaxed axial power distribution control limits  

SciTech Connect (OSTI)

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

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

1987-01-01T23:59:59.000Z

134

Small core axial compressors for high efficiency jet aircraft  

E-Print Network [OSTI]

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

DiOrio, Austin Graf

2012-01-01T23:59:59.000Z

135

Proceedings of the Axial Offset Anomaly (AOA) Science Workshop  

SciTech Connect (OSTI)

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

None

2003-06-01T23:59:59.000Z

136

Parallel plate avalanche chamber as an endcap detector for Time Projection Chamber  

SciTech Connect (OSTI)

A small, 10 x 10 cm/sup 2/, parallel plate avalanche counter has been tested paying special attention to those features which can be important in the Time Projection Chamber. The structure of the test chamber is shown. It has a conversion and drift volume, 11 mm thick, delimited by two stainless steel cross wire grids, of 100 ..mu..m wire diameter and 500 ..mu..mm pitch, identified by HV1 and HV2. The anode is made of thick wires, 100 ..mu..m in diameter spaced every 500 ..mu..m. The amplification gap is 4 mm thick. Below the anode, 1 mm apart, we have paced an identical wire plane, HV4, with wires perpendicular to the anode wires. Both electrodes are equipped with electronics and read out. All measurements were performed with a mixture of argon and methane (83% - 17%), a typical gas for Time Projection Chambers. A multiplication factor up to 10/sup 5/ was attained.

Peisert, A.

1984-01-01T23:59:59.000Z

137

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

SciTech Connect (OSTI)

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

White, A.F.

1980-08-01T23:59:59.000Z

138

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

E-Print Network [OSTI]

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

Grujicic, Mica

139

Heart chambers and whole heart segmentation techniques: review  

E-Print Network [OSTI]

Heart chambers and whole heart segmentation techniques: review Dongwoo Kang Jonghye Woo Piotr J://electronicimaging.spiedigitallibrary.org/ on 01/15/2014 Terms of Use: http://spiedl.org/terms #12;Heart chambers and whole heart segmentation, and reproducible segmentation methods. Figure 1 illustrates an example of segmentation of heart on CT scan. A

Kuo, C.-C. "Jay"

140

aerosol test chamber: Topics by E-print Network  

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

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

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Exciting Internship at the American Arab Chamber of Commerce  

E-Print Network [OSTI]

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

Cinabro, David

142

Overview of Chamber and Power Plant Designs for IFE  

E-Print Network [OSTI]

, to be published in 2011, (ISBN 9780470894392) I will review some of the more complete integrated design studies&E are choice of materials, chamber and building design, tritium inventory, design of tritium processing systemsOverview of Chamber and Power Plant Designs for IFE Wayne Meier Deputy Program Leader Fusion Energy

143

A mechanical mode-stirred reverberation chamber with chaotic geometry  

E-Print Network [OSTI]

A previous research on multivariate approach to the calculation of reverberation chamber correlation matrices is used to calculate the number of independent positions in a mode-stirred reverberation chamber. Anomalies and counterintuitive behavior are observed in terms of number of correlated matrix elements with respect to increasing frequency. This is ascribed to the regular geometry forming the baseline cavity (screened room) of a reverberation chamber, responsible for localizing energy and preserving regular modes (bouncing ball modes). Smooth wall deformations are introduced in order to create underlying Lyapunov instability of rays and then destroy survived regular modes. Numerical full-wave simulations are performed for a reverberation chamber with corner hemispheres and (off-)center wall spherical caps. Field sampling is performed by moving a mechanical carousel stirrer. It is found that wave-chaos inspired baseline geometries improve chamber performances in terms of lowest usable frequencies and number of independent cavity realizations of mechanical stirrers.

Gabriele Gradoni; Franco Moglie; Valter Mariani Primiani

2014-07-06T23:59:59.000Z

144

Vacuum chamber for ion manipulation device  

DOE Patents [OSTI]

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.

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

2014-12-09T23:59:59.000Z

145

E-Print Network 3.0 - axial crush response Sample Search Results  

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

model predicts well the stress-strain response ofFRP confined concrete. 7. The axial... Behavior of Concrete-Filled FRP Tubes Under Bending, Axial Loads, and Combined Loading...

146

E-Print Network 3.0 - axial magnetic bearing Sample Search Results  

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

increase and to take... operations. This paper presents the 3D overall simulation of a 3 Tesla axial magnetic field compact ECRIS... and an axial height of 80 mm. The magnetic...

147

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

E-Print Network [OSTI]

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

Hanley, Brian K. (Brian Kyle)

2010-01-01T23:59:59.000Z

148

E-Print Network 3.0 - axial ratio Sample Search Results  

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

described for these variations. The core axial velocity is of the order of the peak... blade side of the rotor. The axial velocity in all cases is wake-like, being directed...

149

E-Print Network 3.0 - axially symmetric fields Sample Search...  

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

West Summary: velocity zones on flanks of Axial Crustal thickness and Cobb hot spot Gravity field The Cobb hot spot Role... of Axial Crustal thickness and Cobb hot spot Gravity...

150

Effective parameters in axial injection suspension plasma spray process of alumina-zirconia ceramics  

E-Print Network [OSTI]

Effective parameters in axial injection suspension plasma spray process of alumina- zirconia phases using extra small particles as compared to conventional thermal spraying. Suspension spraying% yittria stabilized zirconia was deposited by axial injection SPS process. The effects of principal

Medraj, Mamoun

151

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

E-Print Network [OSTI]

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

Lee, Chung-Sheng

2006-01-01T23:59:59.000Z

152

E-Print Network 3.0 - axial guide field Sample Search Results  

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

Guide,". 10... .K.T., "Exit Flow Field and Performance of Axial Flow Fans," Journal of Fluids Engineering, Vol. 128, pp:332... -LEAKAGE VORTEX MINIMIZATION IN DUCTED AXIAL FANS...

153

E-Print Network 3.0 - axial-flow gas turbine-propeller Sample...  

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

for a substantial portion of aerodynamic losses in axial flow fans... of the major energy loss sources for axial flow fan systems. Despite the close relation between the tip...

154

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

E-Print Network [OSTI]

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

Brest, Université de

155

E-Print Network 3.0 - axial heat conduction Sample Search Results  

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

- Department of Mechanical Engineering, Hongik University Collection: Engineering ; Energy Storage, Conversion and Utilization 9 Observation of Simultaneous Axial and Transverse...

156

Axially Tapered And Bilayer Microchannels For Evaporative Cooling Devices  

DOE Patents [OSTI]

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.

Nilson, Robert (Cardiff, CA); Griffiths, Stewart (Livermore, CA)

2005-10-04T23:59:59.000Z

157

Axial Ge/Si nanowire heterostructure tunnel FETs  

SciTech Connect (OSTI)

The vapor-liquid-solid (VLS) growth of semiconductor nanowires allows doping and composition modulation along their axis and the realization of axial 1 D heterostructures. This provides additional flexibility in energy band-edge engineering along the transport direction which is difficult to attain by planar materials growth and processing techniques. We report here on the design, growth, fabrication, and characterization of asymmetric heterostructure tunnel field-effect transistors (HTFETs) based on 100% compositionally modulated Si/Ge axial NWs for high on-current operation and low ambipolar transport behavior. We discuss the optimization of band-offsets and Schottky barrier heights for high performance HTFETs and issues surrounding their experimental realization. Our HTFET devices with 10 nm PECVD SiN{sub x} gate dielectric resulted in a measured current drive exceeding 100 {mu}A/{mu}m (I/{pi}D) and 10{sup 5} I{sub on}/I{sub off} ratios.

Picraux, Sanuel T [Los Alamos National Laboratory; Daych, Shadi A [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

158

Axially staged combustion system for a gas turbine engine  

DOE Patents [OSTI]

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.

Bland, Robert J. (Oviedo, FL)

2009-12-15T23:59:59.000Z

159

Coral Extension Rate Analysis Using Computed Axial Tomography  

E-Print Network [OSTI]

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

Yudelman, Eleanor Ann

2014-01-10T23:59:59.000Z

160

Nuclear reactor control rod with uniformly changeable axial worth  

SciTech Connect (OSTI)

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

Freeman, T.R.

1987-11-17T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Closed chamber drill stem test detects deep damage  

SciTech Connect (OSTI)

Closed chamber drill stem tests are a relatively new development in drill stem testing. The technique was originated to reduce operational and safety problems caused by hydrate formation during conventional drill stem tests in the Canadian Arctic. During the 1970s, closed chamber testing found widespread acceptance in Canada and is now becoming more widely used in the US. The closed chamber testing method is used in conjunction with conventional drill stem testing tools and equipment. The only additional requirement is a means of continuously monitoring pressure at the surface; therefore, the method can be conducted anywhere conventional drill stem testing equipment is available. The advantage and disadvantages of the system are discussed.

Berkstresser, M.

1982-02-01T23:59:59.000Z

162

Turbine component cooling channel mesh with intersection chambers  

DOE Patents [OSTI]

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).

Lee, Ching-Pang; Marra, John J

2014-05-06T23:59:59.000Z

163

atlas muon chamber: Topics by E-print Network  

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

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

164

atlas muon chambers: Topics by E-print Network  

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

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

165

Carrying Semiautomatic Pistols with a Round in the Chamber  

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

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.

1999-10-28T23:59:59.000Z

166

Mini-chamber, an advanced protection concept for NIF  

SciTech Connect (OSTI)

Inertial confinement fusion (ICF) target debris and ablated near-target materials pose the primary threat to the National Ignition Facility (NIF) final optics debris shields, as well as a major challenge in future inertial fusion energy (IFE) power plants. This work discusses a NIF `mini-chamber,` designed to mitigate the debris threat. Although the NIF base-line design protects against debris using a frost-protected target positioner and refractory first-wall coatings, the mini-chamber provides important flexibility in three areas: debris-shield protection from beyond-design basis shots (i.e. heavy hohlraums, special diagnostics, shields); fielding of large experiments with significant surface ablation; and studying key ablation and gas-dynamics issues for liquid-wall IFE power plants. Key mini-chamber modeling results are presented, followed by discussion of equipment requirements for fielding a NIF mini-chamber. 7 refs., 3 figs.

Peterson, P.F.; Scott, J.M. [Univ. of California, Berkeley, CA (United States)

1996-12-31T23:59:59.000Z

167

E-Cloud Build-up in Grooved Chambers  

E-Print Network [OSTI]

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

Venturini, Marco

2007-01-01T23:59:59.000Z

168

E-Print Network 3.0 - automated chamber system Sample Search...  

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

for 1 h before the measurements with soil chambers were started. We... to a SRC-1 soil respiration chamber), Geir streng. The ... Source: Yakir, Dan - Department of...

169

E-Print Network 3.0 - anterior chamber flare Sample Search Results  

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

ventricular septum comprise a Summary: chambered heart with the future atrial myocardium looping dorsal and anterior to the developing ventricles... ventricular chamber in mef2c...

170

E-Print Network 3.0 - anterior chamber depth Sample Search Results  

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

mesethmoid is not convex... , then a smaller chamber was cut out with a straw. Once an agar chamber was prepared, the ... Source: Hagadorn, Whitey - Department of Geology, Amherst...

171

DIMUON PRODUCTION BY HIGH ENERGY NEUTRINOS AND ANTINEUTRINOS IN THE FERMILAB FIFTEEN-FOOT BUBBLE CHAMBER  

E-Print Network [OSTI]

ANTINEUTRINOS IN THE FERMILAB FIFTEEN-FOOT BUBBLE CHAMBERANTINEUTRINOS IN THE FERMILAB FIFTEEN-FOOT BUBBLE CHAMBER*ANTINEUTRINOS IN THE FERMILAB FIFTEEN-FOOT BUBBLE CHAMBER

Orthel, John L.

2010-01-01T23:59:59.000Z

172

E-Print Network 3.0 - atmosphere simulation chamber Sample Search...  

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

Topic List Advanced Search Sample search results for: atmosphere simulation chamber Page: << < 1 2 3 4 5 > >> 1 Dynamic Chamber System to Measure Gaseous Compounds Emissions...

173

Laser calibration system for the CERES Time Projection Chamber  

E-Print Network [OSTI]

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

Dariusz Miskowiec; Peter Braun-Munzinger

2008-02-15T23:59:59.000Z

174

Chamber technology concepts for inertial fusion energy: Three recent examples  

SciTech Connect (OSTI)

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

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

1997-02-27T23:59:59.000Z

175

Coanda injection system for axially staged low emission combustors  

DOE Patents [OSTI]

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.

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

2012-05-15T23:59:59.000Z

176

SUMMARY ON TITANIUM NITRIDE COATING OF SNS RING VACUUM CHAMBERS.  

SciTech Connect (OSTI)

The inner surfaces of the 248 m Spallation Neutron Source (SNS) accumulator ring vacuum chambers are coated with {approx}100nm of titanium nitride (TiN) to reduce the secondary electron yield (SEY) of the chamber walls. There are approximately 135 chambers and kicker modules, some up to 5m in length and 36cm in diameter, coated with TiN. The coating is deposited by means of reactive DC magnetron sputtering -using a - cylindrical cathode with internal permanent magnets. This cathode configuration generates a deposition-rate sufficient to meet the required production schedule and produces stoichiometric films with good adhesion, low SEY and acceptable outgassing. Moreover, the cathode magnet configuration allows for simple changes in length and has been adapted to coat the wide variety of chambers and components contained within the arcs, injection, extraction, collimation and RF straight sections. Chamber types and quantities as well as the cathode configurations are presented herein. The unique coating requirements of the injection kicker ceramic chambers and the extraction kicker ferrite surface will be emphasized. A brief summary of the salient coating properties is given including the interdependence of SEY as a function of surface roughness and its effect on outgassing.

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

2005-05-16T23:59:59.000Z

177

Influence of loading rate on axially loaded piles in clay  

E-Print Network [OSTI]

. Coyle (Member) ave u ofs (Member) . Hsrsc (Head of Department) May 1984 ABSTRACT Influence of Loading Rate on Axially Loaded Piles in Clay. (May 1984) Enrique Eduardo Garland Ponce, B. S. , Texas A8M University Chairman of Committee: Dr. Jean... and support during all phases of this study. The author also wishes to acknowledge Drs. Harry M. Coyle and David Dubofski who served as members of the advisory committee. Special notes of gratitude to Dr . Wayne A. Dunlap for his aid in the design...

Garland Ponce, Enrique Eduardo

1984-01-01T23:59:59.000Z

178

Sandia National Laboratories: bi-axially oriented superconductor film  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1development Sandia, NREL Release Wavearc-faultbest paper award Sandiansbi-axially

179

Dark matter limits froma 15 kg windowless bubble chamber  

SciTech Connect (OSTI)

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.

Szydagis, Matthew Mark; /Chicago U.

2010-12-01T23:59:59.000Z

180

Axial Ge/Si nanowire heterostructure tunnel FETs.  

SciTech Connect (OSTI)

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

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

2010-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Competition between modes with different axial structures in gyrotrons  

SciTech Connect (OSTI)

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.

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

2014-09-15T23:59:59.000Z

182

Electrostatic waves in carbon nanotubes with an axial magnetic field  

SciTech Connect (OSTI)

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.

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

2013-10-15T23:59:59.000Z

183

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

E-Print Network [OSTI]

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

DeCampo, J A; Raft, P D

1972-01-01T23:59:59.000Z

184

Initial Back-to-Back Fission Chamber Testing in ATRC  

SciTech Connect (OSTI)

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.

Benjamin Chase; Troy Unruh; Joy Rempe

2014-06-01T23:59:59.000Z

185

Method to calibrate fission chambers in Campbelling mode  

SciTech Connect (OSTI)

Fission chambers are neutron detectors which are widely used to instrument experimental reactors such as material testing reactors or zero power reactors. In the presence of a high level mixed gamma and neutron flux, fission chambers can be operated in Campbelling mode (also known as 'fluctuation mode' or 'mean square voltage mode') to provide reliable and precise neutron related measurements. Fission chamber calibration in Campbelling mode (in terms of neutron flux) is usually done empirically using a calibrated reference detector. A major drawback of this method is that calibration measurements have to be performed in a neutron environment very similar to the one in which the calibrated detector will be used afterwards. What we propose here is a different approach based on characterizing the fission chamber response in terms of fission rate. This way, the detector calibration coefficient is independent from the neutron spectrum and can be determined prior to the experiment. The fissile deposit response to the neutron spectrum can then be assessed independently by other means (experimental or numerical). In this paper, the response of CEA made miniature fission chambers in Campbelling mode is studied. We use a theoretical model of the signal to calculate the calibration coefficient. Input parameters of the model come from statistical distribution of individual pulses. Supporting measurements have been made in the CEA Cadarache zero power reactor MINERVE. Results are compared to an empirical Campbelling mode calibration.

Benoit Geslot; Troy C. Unruh; Philippe Filliatre; Christian Jammes; Jacques Di Salvo; Stéphane Bréaud; Jean-François Villard

2011-06-01T23:59:59.000Z

186

Extreme-UV lithography vacuum chamber zone seal  

DOE Patents [OSTI]

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.

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

2001-01-01T23:59:59.000Z

187

Extreme-UV lithography vacuum chamber zone seal  

DOE Patents [OSTI]

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.

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

2003-04-08T23:59:59.000Z

188

Extreme-UV lithography vacuum chamber zone seal  

DOE Patents [OSTI]

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.

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

2003-04-15T23:59:59.000Z

189

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

SciTech Connect (OSTI)

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

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

2010-11-30T23:59:59.000Z

190

E-Print Network 3.0 - axial-flow hydraulic turbines Sample Search...  

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

Axial flow turbine are, instead, characterized by axis... Miller G., Corren D., Armstrong ... Source: Claps, Pierluigi - Dipartimento di Idraulica,Trasporti e Infrastrutture...

191

E-Print Network 3.0 - axial stent strut Sample Search Results  

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

life prediction for cobalt-chromium stents Summary: condi- tions that would lead to strut fracture. 2. Material The stent in question was manufactured from... constrained axially...

192

E-Print Network 3.0 - axial vertebral rotation Sample Search...  

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

aberrant cervical anatomy in tree sloths Summary: , etc.) were used to identify axial positions. We documented vertebral anatomy in a total of 113... five series of the vertebral...

193

E-Print Network 3.0 - axially symmetric electron Sample Search...  

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

James Maggs, and Stephen Vincena Summary: Aks times the radial field. This axial electric field drives electron currents along the magnetic field... fit with a different...

194

E-Print Network 3.0 - axial flux machine Sample Search Results  

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

Michigan Technological University Collection: Engineering 55 A Millimeter-Scale Electric Generator Matthew K. Senesky and Seth R. Sanders Summary: be described as an axial flux...

195

E-Print Network 3.0 - axial flux permanent Sample Search Results  

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

Centre de mathmatiques Collection: Mathematics 37 A Millimeter-Scale Electric Generator Matthew K. Senesky and Seth R. Sanders Summary: be described as an axial flux...

196

E-Print Network 3.0 - axial injection concept Sample Search Results  

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

Fusion 29 Mitigation of Graphite Nozzle Erosion by Boundary-Layer Control in Solid Rocket Motors Summary: -inj nozzle boundary-layer control system injection velocity x axial...

197

E-Print Network 3.0 - axial turbine stages Sample Search Results  

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

Opportunity The Problem Summary: .transfer@durham.ac.uk Small Scale Generator for Wind and Water Turbines < 10 kW "Axial Flux Generator" Every precaution has... Licensing...

198

E-Print Network 3.0 - axially symmetric model Sample Search Results  

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

MASS ON EARTHQUAKE RESPONSE OF Summary: model (DM) than that of lumped mass model (LM). The ratios of maximum response axial forces... that of magnitude of the vertical...

199

E-Print Network 3.0 - axially symmetric space-times Sample Search...  

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

Sciences and Ecology ; Mathematics 19 Hyperelliptic curve of arbitrary genus in geodesic equations Summary: constant axial symmetric space-times Taub-NUT space-time: mass...

200

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

E-Print Network [OSTI]

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

Milton Dean Slaughter

1999-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

E-Print Network 3.0 - axially cracked pressure Sample Search...  

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

Collection: Engineering 2 MATERIAL POINT METHOD CALCULATIONS WITH EXPLICIT CRACKS, FRACTURE PARAMETERS, AND CRACK Summary: under axial impact with a crack in the central disk....

202

Numerical Modeling of Failure in Magnesium Alloys under Axial Compression and Bending for Crashworthiness Applications.  

E-Print Network [OSTI]

??Numerical modeling of failure was performed for magnesium alloys with circular and square cross-sections under axial compression. The failure criterion was employed using material model… (more)

Ali, Usman

2012-01-01T23:59:59.000Z

203

A phenomenological multi-axial constitutive law for switching in polycrystalline ferroelectric ceramics  

E-Print Network [OSTI]

A phenomenological multi-axial constitutive law for switching in polycrystalline ferroelectric; accepted 30 January 2002 Abstract A phenomenological constitutive law for ferroelectric switching due

204

E-Print Network 3.0 - axial sagittal coronal Sample Search Results  

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

Orientation on the Comparability of Pediatric Brain Volumes Using Three-Dimensional MR Data Summary: consisted of coronally ori- ented images except for Groups I (axial) and VI...

205

E-Print Network 3.0 - axial support motion Sample Search Results  

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

Medicine ; Engineering 7 Effect of boundary conditions on axial flow in a concentrated vortex core Richard K. Cohn and Manoochehr M. Koochesfahani Summary: oscil- lating...

206

E-Print Network 3.0 - axial em dente Sample Search Results  

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

Tel Aviv University Collection: Engineering ; Geosciences 5 On the ordering of energy levels in homogeneous magnetic fields Summary: field and in an axially symmetric...

207

E-Print Network 3.0 - axial coupling constants Sample Search...  

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

force and bending moment were coupled. The total maximum moment n... in concrete-filled tube under axial compression load Pn ... Source: NONE; Rizkalla, Sami H. - Department of...

208

E-Print Network 3.0 - axial volumetric 320-detector Sample Search...  

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

flow fan when the fan is operated on its high volumetric flow rate (low... -LEAKAGE VORTEX MINIMIZATION IN DUCTED AXIAL FANS USING NOVEL ... Source: Camci, Cengiz - Department...

209

E-Print Network 3.0 - axial computarizada con Sample Search Results  

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

coupled plasma Summary: axial electromagnet and variously con- figured permanent magnet cuspings to a planar induc- tively... plasma source, both permanent magnets and a...

210

E-Print Network 3.0 - axial field spectrometer Sample Search...  

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

By using both an optimized permanent magnets and the axial... the permanent magnet configurations used with ... Source: Yeom, Geun Young - Materials Engineering...

211

E-Print Network 3.0 - axially loaded magnetic Sample Search Results  

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

magnetic Search Powered by Explorit Topic List Advanced Search Sample search results for: axially loaded magnetic Page: << < 1 2 3 4 5 > >> 1 Wireless Control of Magnetic Helical...

212

E-Print Network 3.0 - axial view inductively Sample Search Results  

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

and Rayleigh numbers close to onset of convection. Axial dipole solutions are subcritical in all Source: Aubert, Julien - Institut de Physique du Globe de Paris Collection:...

213

E-Print Network 3.0 - axial spondyloarthritis treated Sample...  

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

and Rayleigh numbers close to onset of convection. Axial dipole solutions are subcritical in all Source: Aubert, Julien - Institut de Physique du Globe de Paris Collection:...

214

E-Print Network 3.0 - axial vector current Sample Search Results  

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

Power Conversion in Corneal Topography... the two common measures of corneal topogra- phy--axial and instantaneous powers--that are based on corneal... slope or curvature,...

215

E-Print Network 3.0 - axial vector form Sample Search Results  

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

Power Conversion in Corneal Topography... the two common measures of corneal topogra- phy--axial and instantaneous powers--that are based on corneal... slope or curvature,...

216

E-Print Network 3.0 - axial loads Sample Search Results  

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

Steel Research 63 (2007) 165174 www.elsevier.comlocatejcsr Summary: -compacting concrete; Concrete-filled steel tube; Axial load behavior; Ultimate capacity; Confinement...

217

E-Print Network 3.0 - axial force measurement Sample Search Results  

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

AND I. BASDOGAN1004 or radial x or y... -coupling stiffnesses between axial and radial bearing directions are present. A new theoretical model for the direct... functions...

218

E-Print Network 3.0 - axial computada por Sample Search Results  

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

EXPERIMENTALS I DE LA SALUT Summary: i detector. Modalitats d'imatge biomdica: Tomografia axial c.omputada, Ultrasons, Imatge per... distintes modalitats d'imatge biomdica...

219

Chamber and target technology development for inertial fusion energy  

SciTech Connect (OSTI)

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

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

1999-04-07T23:59:59.000Z

220

Simple LMFBR axial-flow friction-factor correlation  

SciTech Connect (OSTI)

Complicated LMFBR axial lead-length averaged friction-factor correlations are reduced to an easy, ready-to-use function of bundle Reynolds number for wire-wrapped bundles. The function together with the power curves to calculate the associated constants are incorporated in a computer preprocessor, EZFRIC. The constants required for the calculation of the subchannels and bundle friction factors are derived and correlated into power curves of geometrical parameters. A computer program, FRIC, which can alternatively be used to accurately calculate these constants is also included. The accurate values of the constants and the corresponding values predicted by the power curves and percentage error of prediction are tabulated for a wide variety of geometries of interest.

Chan, Y.N.; Todreas, N.E.

1982-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Nuclear reactor control rod with uniformly changeable axial worth  

SciTech Connect (OSTI)

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

Freeman, T.R.

1989-04-11T23:59:59.000Z

222

A cryogenic axial-centrifugal compressor for superfluid helium refrigeration  

E-Print Network [OSTI]

CERN's new project, the Large Hadron Collider (LHC), will use superfluid helium as coolant for its high-field superconducting magnets and therefore require large capacity refrigeration at 1.8 K. This may only be achieved by subatmospheric compression of gaseous helium at cryogenic temperature. To stimulate development of this technology, CERN has procured from industry prototype Cold Compressor Units (CCU). This unit is based on a cryogenic axial-centrifugal compressor, running on ceramic ball bearings and driven by a variable-frequency electrical motor operating under low-pressure helium at ambient temperature. The machine has been commissioned and is now in operation. After describing basic constructional features of the compressor, we report on measured performance.

Decker, L; Schustr, P; Vins, M; Brunovsky, I; Lebrun, P; Tavian, L

1997-01-01T23:59:59.000Z

223

Operational Experience with a Cryogenic Axial-Centrifugal Compressor  

E-Print Network [OSTI]

The Large Hadron Collider (LHC), presently under construction at CERN, requires large refrigeration capacity at 1.8 K. Compression of gaseous helium at cryogenic temperatures is therefore inevitable. Together with subcontractors, Linde Kryotechnik has developed a prototype machine. This unit is based on a cryogenic axial-centrifugal compressor, running on ceramic ball bearings and driven by a variable-frequency electrical motor operating at ambient temperature. Integrated in a test facility for superconducting magnets the machine has been commissioned without major problems and successfully gone through the acceptance test in autumn 1995. Subsequent steps were initiated to improve efficiency of this prototype. This paper describes operating experience gained so far and reports on measured performance prior to and after constructional modifications.

Decker, L; Löhlein, K; Purtschert, W; Ziegler, B L; Lebrun, P; Tavian, L; Brunovsky, I; Tucek, L

1998-01-01T23:59:59.000Z

224

Hamilton's equations for a fluid membrane: axial symmetry  

E-Print Network [OSTI]

Consider a homogenous fluid membrane, or vesicle, described by the Helfrich-Canham energy, quadratic in the mean curvature. When the membrane is axially symmetric, this energy can be viewed as an `action' describing the motion of a particle; the contours of equilibrium geometries are identified with particle trajectories. A novel Hamiltonian formulation of the problem is presented which exhibits the following two features: {\\it (i)} the second derivatives appearing in the action through the mean curvature are accommodated in a natural phase space; {\\it (ii)} the intrinsic freedom associated with the choice of evolution parameter along the contour is preserved. As a result, the phase space involves momenta conjugate not only to the particle position but also to its velocity, and there are constraints on the phase space variables. This formulation provides the groundwork for a field theoretical generalization to arbitrary configurations, with the particle replaced by a loop in space.

Riccardo Capovilla; Jemal Guven; Efrain Rojas

2005-05-25T23:59:59.000Z

225

Feedback control of inertial microfluidics using axial control forces  

E-Print Network [OSTI]

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

Prohm, Christopher

2014-01-01T23:59:59.000Z

226

AXIAL SOURCE PROFILE EFFECT ON WASTE PACKAGE TRANSPORTER SHIELDING  

SciTech Connect (OSTI)

The purpose of this scoping calculation is to support preliminary design of the Waste Package (WP) transporter radiation shield configuration. Spent Nuclear Fuel (SNF) is highly radioactive and site personnel must be protected during the period that the WPs are emplaced. Personnel protection is accomplished via a heavily shielded WP transporter that moves the waste from the surface to the emplacement drift. All previous WP transporter shielding calculations have assumed a Design Basis Fuel (DBF) in which the fuel burnup is uniform (e.g. Ref. 7.3, Ref. 7.4, and Ref. 7.12). In reality, SNF burnup varies significantly from one end of the fuel assembly to the other. Since source strengths are dependent upon fuel burnup, a model which varies the fuel burnup along the assembly axis will produce a more accurate depiction of the radiation field surrounding the WP transporter. The objective of this calculation is to determine the need for using the actual axial profile, as opposed to the uniform burnup assumption, in the WP transporter shield design. The scope of the calculation is as follows: (1) Determine the impact of axial source term variation on WP transporter contact dose rates. (2) Determine appropriate shielding modifications to account for expected dose rate peaking effects. Consistent with the previous subsurface shielding analyses, this calculation considers the bounding 21 Pressurized Water Reactor (PWR) WP only. The calculation will need to be revised and extended to Boiling Water Reactor (BWR) SNF upon selection of the WP design for the License Application (LA) and availability of the source terms from the WP Operations Group.

A. Nielsen

1999-06-30T23:59:59.000Z

227

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

SciTech Connect (OSTI)

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.

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

2014-03-24T23:59:59.000Z

228

Cycles in the chamber homology of GL(3).  

E-Print Network [OSTI]

Let F be a nonarchimedean local field and let GL(N) = GL(N,F). We prove the existence of parahoric types for GL(N). We construct representative cycles in all the homology classes of the chamber homology of GL(3).

Anne-Marie Aubert; Samir Hasan; Roger Plymen

229

www.ornl.gov Environmental Chambers at ORNL  

E-Print Network [OSTI]

-air HVAC system, heat pump water heaters, a dehumidifying water heater, solid-state lighting, hybrid solar-by-side chambers can test gas heat pumps, electric heat pumps and air conditioners, gas/electric packaged units, desiccant systems, and small distributed generation/combined heat and power (CHP) systems with capacities

Oak Ridge National Laboratory

230

Thermodynamic Analysis of a single chamber Microbial Eric A. Zielke  

E-Print Network [OSTI]

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

231

Modeling chamber transport for heavy-ion fusion  

SciTech Connect (OSTI)

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.

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

2002-10-01T23:59:59.000Z

232

Harvesting Energy from Wastewater in a 2-Chamber  

E-Print Network [OSTI]

Harvesting Energy from Wastewater in a 2-Chamber Microbial Fuel Cell Sikandar Present day wastewater treatment plants utilize high amounts of energy and are costly to operate. These conventional wastewater treatment plants utilize aerobic bacteria. Organic material in wastewater contains energy that can

233

LASER FUSION CHAMBER DESIGN James P. Blanchard1  

E-Print Network [OSTI]

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

Raffray, A. René

234

Measurements of Film Flow Rate in Heated Tubes with Various Axial Power Distributions  

E-Print Network [OSTI]

Measurements of Film Flow Rate in Heated Tubes with Various Axial Power Distributions by Carl, Measurements of Film Flow Rate in Heated Tubes with Various Axial Power Distributions KTH Nuclear Reactor power is limited by a phenomenon called critical heat flux (CHF). It appears as a sudden detoriation

Haviland, David

235

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

E-Print Network [OSTI]

/surge-model. A model for centrifugal compressors with nonconstant speed was presented in 2]. In 5] a similar model applies to centrifugal compressors. It seems that the modeling and control of an axial com- pression) Table 1: Development in compressor stall/surge- control. A=Axial, C=Centrifugal, M=Modeling, C

Gravdahl, Jan Tommy

236

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

E-Print Network [OSTI]

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

Muradoglu, Metin

237

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

E-Print Network [OSTI]

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

Mayne, Paul W.

238

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

E-Print Network [OSTI]

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

Sergio Dain; Ivan Gentile de Austria

2014-09-19T23:59:59.000Z

239

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

SciTech Connect (OSTI)

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.

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

2013-12-15T23:59:59.000Z

240

Negative particle planar and axial channeling and channeling collimation  

SciTech Connect (OSTI)

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.

Carrigan, Richard A., Jr.; /Fermilab

2009-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Multistage axial-flux PM machine for wheel direct drive  

SciTech Connect (OSTI)

The design of direct-drive wheel motors must comply with diameter restriction due to housing the motor in a wheel rim and allow the achievement of very high torque density and overload capability. Slotless axial-flux permanent magnet machines (AFPMs) prove to be the best candidate for application in electric vehicles as direct-drive wheel motors, as in comparison with conventional machines they allow designs with higher compactness, lightness and efficiency. The paper presents a newly conceived AFPM which has a multistage structure and a water-cooled ironless stator. In the proposed new topology of the machine the space formerly occupied by the toroidal core becomes a water duct, which removes heat directly from the interior surface of the stator winding. The high efficiency of the machine cooling arrangement allows long-term 100% overload operation and great reduction of the machine weight. The multistage structure of the machine is suited to overcome the restriction on the machine diameter and meet the torque required at the wheel shaft. The paper gives guidelines for the design of a multistage AFPM with water-cooled ironless stator, and describes characteristics of a two-stage prototype machine rated 215 N{center_dot}m, 1,100 r/min.

Caricchi, F.; Crescimbini, F.; Mezzetti, F.; Santini, E. [Univ. of Rome La Sapienza (Italy). Dept. of Electrical Engineering] [Univ. of Rome La Sapienza (Italy). Dept. of Electrical Engineering

1996-07-01T23:59:59.000Z

242

Feedback control of inertial microfluidics using axial control forces  

E-Print Network [OSTI]

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

Christopher Prohm; Holger Stark

2014-02-03T23:59:59.000Z

243

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

E-Print Network [OSTI]

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

Li, Perry Y.

244

SciTech Connect: ON THE ANALYSIS OF BUBBLE CHAMBER TRACKS  

Office of Scientific and Technical Information (OSTI)

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

245

Chamber for the optical manipulation of microscopic particles  

DOE Patents [OSTI]

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.

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

1992-01-01T23:59:59.000Z

246

Beam Loss Ion Chamber System Upgrade for Experimental Halls  

SciTech Connect (OSTI)

The Beam loss Ion Chamber System (BLICS) was developed to protect Jefferson Labs transport lines, targets and beam dumps from a catastrophic ''burn through''. Range changes and testing was accomplished manually requiring the experiment to be shut down. The new upgraded system is based around an ''off the shelf'' Programmable Logic Controller located in a single control box supporting up to ten individual detectors. All functions that formerly required an entry into the experimental hall and manual adjustment can be accomplished from the Machine Control Center (MCC). A further innovation was the addition of a High Voltage ''Brick'' at the detector location. A single cable supplies the required voltage for the Brick and a return line for the ion chamber signal. The read back screens display range, trip point, and accumulated dose for each location. The new system is very cost effective and significantly reduces the amount of lost experimental time.

D.W. Dotson; D.J. Seidman

2005-05-16T23:59:59.000Z

247

HOM Sensitivity in the PEP-II HER Vacuum Chamber  

SciTech Connect (OSTI)

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.

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

2010-02-10T23:59:59.000Z

248

Z .Physics of the Earth and Planetary Interiors 108 1998 129141 Short and long baseline tiltmeter measurements on axial  

E-Print Network [OSTI]

measurements on axial seamount, Juan de Fuca Ridge Maya Tolstoy ) , Steven Constable 1 , John Orcutt 2 , Hubert

Tolstoy, Maya

249

Combustion of Shock-Dispersed Fuels in a Chamber  

SciTech Connect (OSTI)

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

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

2003-04-23T23:59:59.000Z

250

Progress and critical issues for IFE blanket and chamber research  

SciTech Connect (OSTI)

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

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

1999-06-23T23:59:59.000Z

251

Light-scattering properties of plate and column ice crystals generated in a laboratory cold chamber  

E-Print Network [OSTI]

with a diode laser beam. This cloud chamber produces distinct plate and hollow column ice crystal types. The cloud chamber developed at the Desert Re- search Institute has been used to produce ice clouds composedLight-scattering properties of plate and column ice crystals generated in a laboratory cold chamber

Liou, K. N.

252

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

DOE Patents [OSTI]

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.

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

2011-03-08T23:59:59.000Z

253

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

E-Print Network [OSTI]

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

Simpson, Shay Lynn

1996-01-01T23:59:59.000Z

254

E-Print Network 3.0 - axial seamount harbor Sample Search Results  

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

present in the axial zone of the GSC has been determined using high... likelihood model Smith and Cann, 1992. The number of ... Source: Graham, David W. - College of Oceanic and...

255

E-Print Network 3.0 - axial skeletal manifestations Sample Search...  

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

for: axial skeletal manifestations Page: << < 1 2 3 4 5 > >> 1 insight review articles NATURE | VOL 423 | 15 MAY 2003 | www.nature.comnature 343 Summary: develop- mental pathways....

256

E-Print Network 3.0 - axially symmetric divertor Sample Search...  

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

of High Heat-Flux Plasma-Flow for Summary: divertor plates. Axial and radial profile measurements of heat and particle fluxes showed that the observed... 1 FTPP1-33...

257

E-Print Network 3.0 - axial electric field Sample Search Results  

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

associated toroidal... . This alternative but equivalent way for produc- ing the radial electric field Er drives a current nearly along... that is axially non-uniform as in Fig....

258

E-Print Network 3.0 - axially deformed transition Sample Search...  

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

stainless steel subjected to in situ biaxial loading Summary: the loading sequence in the elastic-plastic transition (case r hh r zz 0:7). (b) Axial and hoop lattice... a...

259

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

E-Print Network [OSTI]

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

Lei, Vai-Man

2006-01-01T23:59:59.000Z

260

The effect of static and dynamic misalignment on ball bearing radial stiffness for variable axial preloads  

E-Print Network [OSTI]

The primary objective of the research project was to determine through rotordynamic computer modeling and experimental testing, the radial stiffness of a symmetric angular contact ball bearing for static and dynamic misalignment under various axial...

Ertas, Bugra H

2001-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

A co-axially configured submillimeter spectrometer and investigations of hydrogen bound molecular complexes  

E-Print Network [OSTI]

The development of a co-axially configured submillimeter spectrometer is reported. The spectrometer has been constructed to observe molecular complexes that exhibit non-covalent interactions with energies much less than that of a traditional...

McElmurry, Blake Anthony

2009-05-15T23:59:59.000Z

262

Bounds for axially symmetric linear perturbations for the extreme Kerr black hole  

E-Print Network [OSTI]

We obtain remarkably simple integral bounds for axially symmetric linear perturbations for the extreme Kerr black hole in terms of conserved energies. From these estimates we deduce pointwise bounds for the perturbations outside the horizon.

Dain, Sergio

2015-01-01T23:59:59.000Z

263

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

DOE Patents [OSTI]

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.

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

1982-10-28T23:59:59.000Z

264

E-Print Network 3.0 - axial power distribution Sample Search...  

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

and cyclotron mode in the precision trap. The measurement yields the ion's axial energy distribution... of the trapping potential is to measure the depth of the dip in the...

265

E-Print Network 3.0 - axial free-electron laser Sample Search...  

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

free-electron laser Search Powered by Explorit Topic List Advanced Search Sample search results for: axial free-electron laser Page: << < 1 2 3 4 5 > >> 1 JOURNAL DE PHYSIQUE...

266

E-Print Network 3.0 - axial crystal fields Sample Search Results  

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

A.C. Neubrand b, J.P. Garandet b... growth. Experiments have been carried out under a permanent uniform axial magnetic field of intensity up... to 1.35T. The field is seen to have...

267

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

E-Print Network [OSTI]

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

Clifton, David (David Madison)

2014-01-01T23:59:59.000Z

268

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

E-Print Network [OSTI]

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

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

2007-04-11T23:59:59.000Z

269

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

E-Print Network [OSTI]

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

Todreas, Neil E.

1965-01-01T23:59:59.000Z

270

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

E-Print Network [OSTI]

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

Alexandrou, Constantia

271

E-Print Network 3.0 - axial mixing holdup Sample Search Results  

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

Purge velocity, ms y i Mole... of component i in purge z Axial position in bed, m ffl Void fraction of bed ae B Density of the bed, kgm 3 Source: Barton, Paul I. - Department...

272

Experiments and analysis for an axially heterogeneous LMR assembly at ZPPR  

SciTech Connect (OSTI)

Experiments in ZPPR-17 provided physics data for a full-scale (700 MWe) axially heterogeneous LMR. Measurements and analysis are reported for control rod worths, reaction rate distributions, gamma dose distribution, sodium void worths and criticality. Agreement between measurement and calculation are generally satisfactory, but the axial heterogeneity did introduce analytical complications. Some calculational methods gave less good agreement with measurements than in previous homogeneous or radially heterogeneous assemblies. 10 refs., 7 figs., 6 tabs.

Collins, P.J.; Brumbach, S. B.

1988-01-01T23:59:59.000Z

273

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

SciTech Connect (OSTI)

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.

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

2009-08-26T23:59:59.000Z

274

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

SciTech Connect (OSTI)

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

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

2011-12-02T23:59:59.000Z

275

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

SciTech Connect (OSTI)

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

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

1989-03-01T23:59:59.000Z

276

Statistics of the electromagnetic response of a chaotic reverberation chamber  

E-Print Network [OSTI]

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

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

2014-09-20T23:59:59.000Z

277

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

SciTech Connect (OSTI)

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

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

2012-03-15T23:59:59.000Z

278

Wire-chamber radiation detector with discharge control  

DOE Patents [OSTI]

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.

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

1982-03-29T23:59:59.000Z

279

Heat transfer and pollutant formation mechanisms in insulated combustion chambers  

SciTech Connect (OSTI)

The authors have studied the quenching situation as it can be found in constant volume combustion chambers for a methane flame over a range of wall temperatures between 300 K and 600 K using Direct Numerical Simulation. To do this, the authors solved the fully compressible, one-dimensional Navier-Stokes equations with detailed mechanisms for kinetics and diffusion. This approach allows to compare various reaction schemes, to identify the most important species and reaction paths, and to investigate the influence of different modeling assumptions. The computational results show that the dimensional wall heat flux increases with wall temperature over the whole range of wall temperatures studied; this agrees well with the most recent measurements in a strongly improved experimental setup. It is found that the wall can be modeled as chemically inert and thermal diffusion processes are negligible for low wall temperatures between 300 K and 400 K. However, at higher temperatures, due to a dramatically increasing radical concentration (H, Oh, OH) at the wall, both become increasingly important leading to large heat release rates directly at the metallic wall surface of the combustion chamber, and can thus not be neglected in the modeling of the quenching process. Furthermore, these high radical concentrations adjacent to the wall indicate that the uncertainties in wall heat flux measurements at high wall temperatures could be underestimated by the experimentalists. The UHC concentration at a wall temperature of 600 K is about 20 times smaller than for 300 K after quenching. 37 refs., 12 figs., 1 tab.

Popp, P.; Baum, M.

1995-12-31T23:59:59.000Z

280

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

SciTech Connect (OSTI)

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

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

2003-04-22T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Slag monitoring system for combustion chambers of steam boilers  

SciTech Connect (OSTI)

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.

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

2009-07-01T23:59:59.000Z

282

Atmospheric-pressure plasma decontamination/sterilization chamber  

DOE Patents [OSTI]

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.

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

2001-01-01T23:59:59.000Z

283

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

SciTech Connect (OSTI)

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.

Daugherty, W.

2013-09-30T23:59:59.000Z

284

Development of a multistep parallel-plate chamber as time projection chamber end-cap or vertex detector  

SciTech Connect (OSTI)

In the course of development of the multistep avalanche chamber the authors have realized several multiple electrode parallel-plate devices exhibiting stable gains well in excess of 10/sup 5/ which are thus capable of detecting minimum ionizing particles. This paper presents the design and discusses the performance of a two-step parallel-plate avalanche chamber. A region of moderate electric field --the drift region where charges are released by ionizing radiation--is followed by two layers of comparable and very high field where charge multiplication occurs. Owing to the choice of the electrodes--either cross-wire meshes or parallel thick-wire grids at small pitch--the electric field is uniform over most of the gaps, and charge multiplication proceeds through a parallel-plate avalanche mode. In order to obtain a fast signal and a reduced avalanche spread in their prototypes, the authors have adopted rather narrow typical gaps of 4 mm for the first amplification region and 1 mm for the second. To avoid edge sparking, they have used either a gap increase at the edges or the insertion of thin mylar foil around the frame's edges. The last electrode in the structure, made with a printed-circuit board, is the only one equipped with electronics and is conveniently operated at ground potential. At regular intervals, four rows of pads are used to determine the coordinates of tracks in selected positions. Argon (90%) and methane (10%) comprise the gas filling.

Peisert, A.; Charpak, G.; Sauli, F.; Viezzoli, G.

1984-02-01T23:59:59.000Z

285

Development of Glass Resistive Plate Chambers for INO  

E-Print Network [OSTI]

The India-based Neutrino Observatory (INO) collaboration is planning to build a massive 50kton magnetised Iron Calorimeter (ICAL) detector, to study atmospheric neutrinos and to make precision measurements of the parameters related to neutrino oscillations. Glass Resistive Plate Chambers (RPCs) of about 2m X 2m in size are going to be used as active elements for the ICAL detector. We have fabricated a large number of glass RPC prototypes of 1m X 1m in size and have studied their performance and long term stability. In the process, we have developed and produced a number of materials and components required for fabrication of RPCs. We have also designed and optimised a number of fabrication and quality control procedures for assembling the gas gaps. In this paper we will review our activities towards development of glass RPCs for the INO ICAL detector and will present results of the characterisation studies of the RPCs.

Satyanarayana Bheesette; for the INO collaboration

2008-10-26T23:59:59.000Z

286

E-Print Network 3.0 - anterior chamber angle Sample Search Results  

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

pits face anteriorly, wide "detection range + anterior... angle - records ambient air Higher Sensitivity dual chamber pit improves sensitivity detect 0.001 deg. C... are...

287

Liquid fuel vaporizer and combustion chamber having an adjustable thermal conductor  

DOE Patents [OSTI]

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.

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

2014-03-04T23:59:59.000Z

288

Mixed reactant single chamber fuel cell, using products generated from the electrolysis of an aqueous electrolyte.  

E-Print Network [OSTI]

??A Mixed Reactant Single Chamber (MRSC) Fuel Cell is a relatively recent concept in the field of fuel cell engineering originally developed in the late… (more)

Jost, William C.

2008-01-01T23:59:59.000Z

289

E-Print Network 3.0 - atlas vacuum chamber Sample Search Results  

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

Particle Physics Summary: monoxide and dioxide. Hydrocarbons are pumped with lumped ion pumps. The ATLAS experimental vacuum chamber... ). There will be 4 big experiments operating...

290

Methane ionization chamber to search for spin-dependent dark matter interactions  

E-Print Network [OSTI]

A liquid-methane ionization chamber is proposed as a setup to search for spin-dependent interactions of dark-matter particles with hydrogen

B. M. Ovchinnikov; V. V. Parusov; V. A. Bednyakov

2005-08-04T23:59:59.000Z

291

IMPEDANCE OF ELECTRON BEAM VACUUM CHAMBERS FOR THE NSLS-II STORAGE RING.  

SciTech Connect (OSTI)

In this paper we discuss computation of the coupling impedance of the vacuum chambers for the NSLS-II storage ring using the electromagnetic simulator GdfidL [1]. The impedance of the vacuum chambers depends on the geometric dimensions of the cross-section and height of the slot in the chamber wall. Of particular concern is the complex geometry of the infrared extraction chambers to be installed in special large-gap dipole magnets. In this case, wakefields are generated due to tapered transitions and large vertical-aperture ports with mirrors near the electron beam.

BLEDNYKH,A.; KRINSKY, S.

2007-06-25T23:59:59.000Z

292

E-Print Network 3.0 - acoustic spark chambers Sample Search Results  

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

Measurements of a Laser- Summary: -sectional view of waterline PFL, liquid load resistor, and spark gap chamber. The electrodes are copper... a pulse- forming line (PFL)...

293

Simulation of Enhanced-Explosive Devices in Chambers and Tunnels  

SciTech Connect (OSTI)

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

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

2007-06-05T23:59:59.000Z

294

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

DOE Patents [OSTI]

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.

Haas, W.M.B.

1983-06-23T23:59:59.000Z

295

Axial seal system for a gas turbine steam-cooled rotor  

DOE Patents [OSTI]

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.

Mashey, Thomas Charles (Anderson, SC)

2002-01-01T23:59:59.000Z

296

Analysis of the behavior of 5 axially loaded single piles in sand at Hunter's Point  

E-Print Network [OSTI]

ANALYSIS OF THE BEHAVIOR OF 5 AXIALLY LOADED SINGLE PILES IN SAND AT HUNTER'S POINT A Thesis by CHER MIN RON Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirement for the degree... of MASTER OF SCIENCE May 1989 Major Subject; Civil Engineering ANALYSIS OF THE BEHAVIOR OF 5 AXIALLY LOADED SINGLE PILES IN SAND AT HUNTER'S POINT A Thesis by GHEE MIN RON Approved as to style and content by: Jean-Louis Briaud Chairman of Committee...

Kon, Chee Min

1989-01-01T23:59:59.000Z

297

Investigation of the axial and radial thrusts in a centrifugal pump  

E-Print Network [OSTI]

Major Subject: Mechanical Engineering INVESTIGATION QF THE AXIAL AND RADIAL THRUSTS IN A CENTRIFUGAL PUMP A Thesis by CHQNG HWAN PARK Approved as to style and content by: eter Jenkins (C 'rman of Committee) Dr Srrra un aram (Member) Dr. R. R... of absolute flow velocity at outlet of impeller (ft/sec) Fa Fb diameter (in) axial thrust (lb) force acting on the back-faces of impeller (lb) Fr Hd H Hs Ht kx kx Pd P(r) force acting on the frontal face of impeller (lb) radial thrust (lb...

Park, Chong Hwan

1984-01-01T23:59:59.000Z

298

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

DOE Patents [OSTI]

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.

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

2004-09-21T23:59:59.000Z

299

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

300

Source of methane and methods to control its formation in single chamber microbial electrolysis cells  

E-Print Network [OSTI]

Source of methane and methods to control its formation in single chamber microbial electrolysis online 31 March 2009 Keywords: Hydrogen Microbial electrolysis cell (MEC) Methane Single chamber Exoelectrogenic a b s t r a c t Methane production occurs during hydrogen gas generation in microbial electrolysis

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

302

Boundary conditions for the computation of thermo-acoustic modes in combustion chambers  

E-Print Network [OSTI]

Boundary conditions for the computation of thermo-acoustic modes in combustion chambers Camilo F LES or Helmholtz solver computations in aeronautical combustion chambers, it is crucial to impose the right boundary conditions at both inlet and outlet of the combustion system. This means providing

303

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

E-Print Network [OSTI]

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

Abdou, Mohamed

304

Hydrogen production using single-chamber membrane-free microbial electrolysis cells  

E-Print Network [OSTI]

efficiencies of hydrogen fuel cells in converting hydrogen to electricity. The development of advancedHydrogen production using single-chamber membrane-free microbial electrolysis cells Hongqiang Hu., Hydrogen production using single-chamber membrane-free microbial electrol- ysis cells, Water Research (2008

Tullos, Desiree

305

Non-Axial Octupole Deformations and Tetrahedral Symmetry in Heavy Nuclei  

SciTech Connect (OSTI)

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

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

2005-11-21T23:59:59.000Z

306

EXPERIMENTAL INVESTIGATIONS ON THE DESIGN OF A DUCTED COUNTER-ROTATING AXIAL FLOW FANS SYSTEM  

E-Print Network [OSTI]

[] Number of blades FR [] Front rotor R [mm] Blade radius RR [] Rear rotor CRS [] Counter-rotating system W to a conventional rotor or to a rotor-stator stage. The study of the variation of the rotation rates ratio show of the axial distance be- tween rotors does not seem to change the overall per- formances. This system has thus

Boyer, Edmond

307

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

E-Print Network [OSTI]

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

Weichert, Stephanie April

2012-02-07T23:59:59.000Z

308

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

E-Print Network [OSTI]

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

Gurnett, Donald A.

309

E-Print Network 3.0 - axial x-ray power Sample Search Results  

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

for: axial x-ray power Page: << < 1 2 3 4 5 > >> 1 Martin Elvis, X-ray & XUV Active Optics, Soleil, 14-15 Dec 2006 Active X-ray OpticsActive X-ray Optics Summary: 1 Martin...

310

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

E-Print Network [OSTI]

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

Demazière, Christophe

311

A study of swirl and axial velocity profile effects on orifice flowmeters  

E-Print Network [OSTI]

with [ ] ratios of 0.43, 0.45, 0.484, 0.55, 0.6, 0.65, 0.7 and 0.726 are studied at both flow rates. The response of each orifice meter to the disturbance is measured by determining the axial pressure distribution near the orifice plate, and by determining...

Hauglie, Jayden Edward

1994-01-01T23:59:59.000Z

312

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

313

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

314

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

E-Print Network [OSTI]

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

Kazuhiro Tominaga; Motoyuki Saijo; Kei-ichi Maeda

1999-09-20T23:59:59.000Z

315

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

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

316

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

DOE Patents [OSTI]

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.

Whitehead, John C. (Davis, CA)

2001-01-01T23:59:59.000Z

317

Abstract This paper investigates the steady-state and the transient performances of an axial magnetic coupling by using  

E-Print Network [OSTI]

and measurements. Index Terms-- Analytical model, magnetic field, axial coupling, permanent magnets, pull-pitch ratio p Pole-pair number Torque angle Br Remanence of the permanent magnets K Torsional stiffness II tolerate shaft misalignment. As shown in Fig. 1, the studied axial magnetic coupling consists of two discs

Paris-Sud XI, Université de

318

Progress In Electromagnetics Research M, Vol. 35, 173182, 2014 Three-Dimensional Analytical Model for an Axial-Field  

E-Print Network [OSTI]

--In this paper, we propose an analytical method for modeling a permanent magnets axial field magnetic coupling. Shaft Rout Magnets Soft-Iron yoke h h Rin e To load From motor Magnetic coupling Figure 1. Structure equipped with axially magnetized permanent magnets (PMs). The PMs are glued on an iron yoke to form a north

Paris-Sud XI, Université de

319

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

E-Print Network [OSTI]

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

Camci, Cengiz

320

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

E-Print Network [OSTI]

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

de Gispert, Adrià

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Using large environmental chamber technique for gaseous contaminant removal equipment test  

SciTech Connect (OSTI)

The US Association of Home Appliance Manufacturers (AHAM) has set a voluntary standard for testing the initial dust-removal capacity of portable air cleaners. In the authors` test of portable air cleaners for the local consumer council, the AHAM method was extended to test the initial removal capacity for gaseous phase pollutants. Also, carbon filters` efficiency change over time in toluene removal on a number of air cleaners was tested. In using a large chamber to carry out these tests, the chamber wall adsorption and re-emission effects were experimentally quantified. These tests indicated that a large chamber, with its wall surface adsorption controlled, is simple and robust to use to quantify the initial cleaning capacity for gaseous phase pollutants. Based on these test results, a large chamber method is proposed to test the performance lifetimes of portable air cleaners. The system advantages of the method over the in-duct performance life test methods are that no continuous air-cleaning system is required and that the chamber`s humidity and temperature can be maintained at the desired values more easily with the combination of a unitary dehumidifier and a bubbler system. This paper will present the trial results with portable air cleaner tests and discuss the large environmental chamber techniques.

Niu, J.; Tung, T.C.W.; Chui, V.W.Y. [Hong Kong Polytechnic Univ. (Hong Kong). Dept. of Building Services Engineering

1998-12-31T23:59:59.000Z

322

Plastic ball and streamer chamber experiments at the Bevalac  

SciTech Connect (OSTI)

Single particle inclusive experiments, and experiments that additionally measure a few correlations like the associated multiplicity, have provided the main contribution to our present understanding of high energy heavy ion collisions. The results from those experiments are in overall agreement with calculations of the cascade and hydrodynamical models. In the cascade model the collision of two nuclei is simulated as a cascade of nucleon-nucleon collisions using measured N-N cross sections. The hydrodynamical model, on the other hand, describes the nuclear collision as that of two fluids and makes use of a nuclear equation of state relating thermal and compressional energy densities to pressure. The pressure field dominates the expansion phase and leads to collective flow of the reaction products in a preferred direction. The observation of such effects in inclusive experiments is not well established. Collective effects that manifest themselves in the shape of the event in phase space are expected to be seen best in the new complete event detectors that measure the final state as exclusively as presently possible by measuring most of the charged particles emitted in the reaction. In addition, those detectors are well suited to test macroscopic concepts such as equilibrium and temperature. Global methods like the sphericity or thrust analysis take into account all the correlations measured in the event and are specially designed to determine the shape of an event in phase space and thus to define a reaction plane. Recent data from the Plastic Ball and the streamer chamber experiments, the first complete event detectors in use at the Bevalac, are presented in this report.

Ritter, H.G.

1982-07-01T23:59:59.000Z

323

GEOPHYSICAL RESEARCH LETTERS, VOL. 23, NO. 17, PAGES 2275-2278, AUGUST 15, 1996 SeafloorMagnetotelluricSoundingAboveAxial Seamount  

E-Print Network [OSTI]

MagnetotelluricSoundingAboveAxial Seamount Graham Heinson Schoolof EarthSciences,FlindersUniversity,BedfordPark,Australia Steven Constable

Constable, Steve

324

Synthesis, fabrication and characterization of Ge/Si axial nanowire heterostructure tunnel FETs  

SciTech Connect (OSTI)

Axial Ge/Si heterostructure nanowires allow energy band-edge engineering along the axis of the nanowire, which is the charge transport direction, and the realization of asymmetric devices for novel device architectures. This work reports on two advances in the area of heterostructure nanowires and tunnel FETs: (i) the realization of 100% compositionally modulated Si/Ge axial heterostructure nanowires with lengths suitable for device fabrication and (ii) the design and implementation of Schottky barrier tunnel FETs on these nanowires for high-on currents and suppressed ambipolar behavior. Initial prototype devices resulted in a current drive in excess of 100 {micro}A/{micro}m (I/{pi}D) and 10{sup 5} I{sub on}/I{sub off} ratios. These results demonstrate the potential of such asymmetric heterostructures (both in the semiconductor channel and metal-semiconductor barrier heights) for low-power and high performance electronics.

Picraux, Samuel T [Los Alamos National Laboratory; Dayeh, Shadi A [Los Alamos National Laboratory

2010-01-01T23:59:59.000Z

325

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

SciTech Connect (OSTI)

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

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

1989-01-01T23:59:59.000Z

326

Comparison of the effects of pressure and axial load on tapered connections  

E-Print Network [OSTI]

. OO RX1RL FQHii [LBS. ) (XI Qs } 120. 00 ll1II. 00 Figure 41. Axial Force versus Hoop Stress-Test 1 4. 65 2 7/0 iN. RPI EL~E LUNG-. 362 I', sLL-NBQ 10. 4 & C/) ~el to 3N Th * ' 1, 3, 8 X~~ +Theoretical, 1, 10, 5, 6 18, 10 68, 6 o o G N..., 6 e 58 6 18, 10 0. 0 I ? ?- 21. 00 02. 00 20. 00 04 GG F00, 00 120. 00 RX1RL EQREi iLBS. 1 &Xloa ) Figure 43. Axial Force versus Longitudinal Stress-Test T2. 67 o o 4 I/2 IN. BUTTRESS-. 430 NHLL-NBO 19. Q e o o o Ill rv- ID &o co V) o...

Till, Larry Percy

2012-06-07T23:59:59.000Z

327

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

SciTech Connect (OSTI)

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.

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

2012-04-06T23:59:59.000Z

328

Using electron scattering to constrain the axial-vector form factor  

E-Print Network [OSTI]

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

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

2015-01-16T23:59:59.000Z

329

Fixing Two-Nucleon Weak-Axial Coupling L_{1,A} From mu-d Capture  

E-Print Network [OSTI]

We calculate the muon capture rate on the deuteron to next-to-next-to-leading order in the pionless effective field theory. The result can be used to constrain the two-nucleon isovector axial coupling L_{1,A} to +/- 2 fm^3 if the muon capture rate is measured to 2% level. From this, one can determine the neutrino-deuteron break up reactions and the pp-fusion cross section in the sun to a same level of accuracy.

Jiunn-Wei Chen; Takashi Inoue; Xiangdong Ji; Yingchuan Li

2006-01-11T23:59:59.000Z

330

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

E-Print Network [OSTI]

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

Enrico Meggiolaro

2014-10-14T23:59:59.000Z

331

Using electron scattering to constrain the axial-vector form factor  

E-Print Network [OSTI]

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

González-Jiménez, R; Donnelly, T W

2015-01-01T23:59:59.000Z

332

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

E-Print Network [OSTI]

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

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

2014-11-04T23:59:59.000Z

333

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

E-Print Network [OSTI]

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

V. Ferrari; K. D. Kokkotas

2000-08-23T23:59:59.000Z

334

Design and market considerations for axial flux superconducting electric machine design  

E-Print Network [OSTI]

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

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

2013-01-01T23:59:59.000Z

335

Torsional Alfven Waves in Solar Magnetic Flux Tubes of Axial Symmetry  

E-Print Network [OSTI]

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

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

2015-01-01T23:59:59.000Z

336

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

SciTech Connect (OSTI)

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.

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

2014-01-01T23:59:59.000Z

337

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

SciTech Connect (OSTI)

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

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

2014-09-26T23:59:59.000Z

338

E-Print Network 3.0 - atlas mdt chambers Sample Search Results  

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

Page: << < 1 2 3 4 5 > >> 1 CHRISTOPH AMELUNG Date of birth July 14, 1971 (DetmoldGermany) Summary: on the optical alignment system of the ATLAS MDT chambers July 2002 -...

339

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

E-Print Network [OSTI]

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

Porter, Nathaniel R., Jr

2013-01-01T23:59:59.000Z

340

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

E-Print Network [OSTI]

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

An, Ju Jin

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

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

E-Print Network [OSTI]

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

Raffray, A. René

342

Study of Low Speed Flow Cytometry for Diffraction Imaging with Different Chamber  

E-Print Network [OSTI]

for optimization of the chamber design and improvement of the cell positioning accuracy for study of slow moving utilize a sheath nozzle with a conical end or orifice for hydrodynamic focusing the fluid injected

343

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

E-Print Network [OSTI]

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

Lai, Changquan

2010-01-01T23:59:59.000Z

344

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

E-Print Network [OSTI]

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

Grieco, John Paul

1994-01-01T23:59:59.000Z

345

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

DOE Patents [OSTI]

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

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

1991-01-01T23:59:59.000Z

346

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

DOE Patents [OSTI]

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

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

1990-03-19T23:59:59.000Z

347

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

SciTech Connect (OSTI)

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

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

2014-03-01T23:59:59.000Z

348

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

ScienceCinema (OSTI)

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

Glaser, Don

2011-04-28T23:59:59.000Z

349

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

SciTech Connect (OSTI)

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

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

2006-05-24T23:59:59.000Z

350

Palladium-Catalyzed Enantioselective ?-Arylation and ?-Vinylation of Oxindoles Facilitated by an Axially Chiral P-Stereogenic Ligand  

E-Print Network [OSTI]

The enantioselective ?-arylation and ?-vinylation of oxindoles catalyzed by Pd and a biarylmonophosphine ligand with both axial and phosphorus-based chirogenicity is reported. The resultant quaternary carbon stereocenters ...

Taylor, Alexander M.

351

Effect of Temporal Acquisition Parameters on the Image Quality of Ultrasound Axial Strain Time-constant Elastograms  

E-Print Network [OSTI]

constant (TC) have been developed. The axial strain TC is a parameter that is related to the viscoelastic and poroelastic behavior of tissues. Estimation of this parameter can be done using curve fitting methods. However, the effect of temporal...

Varghese, Joshua

2011-08-02T23:59:59.000Z

352

Experiments and analysis for an axially heterogeneous liquid-metal reactor assembly at the zero-power physics reactor  

SciTech Connect (OSTI)

Experiments in zero-power physics reactor 17 provided physics data for a full-scale axially heterogeneous 650-MW(electric) liquid-metal reactor. Measurements and analysis are reported for control rod worths, reaction rate distributions, gamma dose distributions, sodium void worths, and criticality. Agreement between measurement and calculation is generally satisfactory, but the axial heterogeneity did introduce analytical complications. Design-level calculation methods gave somewhat worse agreement with measurement than in previous homogeneous or radially heterogeneous assemblies.

Brumbach, S.B.; Collins, P.J. (Argonne National Lab., Idaho Falls, ID (USA))

1989-11-01T23:59:59.000Z

353

Method for operating a nuclear reactor to accommodate load follow while maintaining a substantially constant axial power distribution  

SciTech Connect (OSTI)

This invention provides a method of operating a nuclear reactor having a negative reactivity moderator temperature coefficient with the object of maintaining a uniform and symmetric xenon distribution above and below substantially the center of the core over a substantial axial length of the core during normal reactor operation including load follow. In one embodiment variations in the xenon distribution are controlled by maintaining a substantially symmetric axial power distribution. The axial offset, which is employed as an indication of the axial power distribution, is maintained substantially equal to a target value , which is modified periodically to account for core burnup. A neutron absorbing element within the core coolant, or moderator, is employed to assist control of reactivity changes associated with changes in power, with the full-length control rods mainly employed to adjust variations in the axial power distribution while the part-length rodsremain completely withdrawn from the fuel region of the core. Rapid changes in reactivity are implemented, to accommodate corresponding changes in load, by a controlled reduction of the core coolant temperature. Thus, active core coolant temperature control is employed to control the reactivity of the core during load follow operation and effectively increase the spinning reserve capability of a power plant without altering the axial power distribution.

Mueller, N.P.; Rossi, C.E.; Scherpereel, L.R.

1980-09-16T23:59:59.000Z

354

A study of the design procedure and the performance characteristics of axial exhaust fans  

E-Print Network [OSTI]

of the requirements for the degxee of %%STER OF SCIENCE IN NECHM3EEL ENGINEERIMG August, 19/9 COBTEEITS Intoroduct'o9. on o e e ~ ~ ~ ~ ~ e ~ e ~ ~ ~ ~ ~ 1 Ia Derivation of Fan Lass ~ ~ ~ ~ ~ ~ ~ ~ ~ 2 XI Description of Test Apparatus . . . . . ~. . . 7 XII... by s reversible electric motor operated by a reversing motor control switch, which is conveniently located near the Inclined manometer connected, to the pitot tube which measures the static pressure inside the plenum chamber. The followiug equipment composes...

Barker, Gilbert Hamilton

2012-06-07T23:59:59.000Z

355

Determing Degradation Of Fiberboard In The 9975 Shipping Package By Measuring Axial Gap  

SciTech Connect (OSTI)

Currently, thousands of model 9975 transportation packages are in use by the US Department of Energy (DOE); the design of which has been certified by DOE for shipment of Type B radioactive and fissile materials in accordance with Part 71, Title 10 Code of Federal Regulations (CFR), or 10 CFR 71, Packaging and Transportation of Radioactive Material. These transportation packages are also approved for the storage of DOE-STD-3013 containers at the Savannah River Site (SRS). As such, the 9975 has been continuously exposed to the service environment for a period of time greater than the approved transportation service life. In order to ensure the material integrity as specified in the safety basis, an extensive surveillance program is in place in K-Area Complex (KAC) to monitor the structural and thermal properties of the fiberboard of the 9975 shipping packages. The surveillance approach uses a combination of Non-Destructive Examination (NDE) field surveillance and Destructive Examination (DE) lab testing to validate the 9975 performance assumptions. The fiberboard in the 9975 is credited with thermal insulation, criticality control and resistance to crushing. During surveillance monitoring in KAC, an increased axial gap of the fiberboard was discovered on selected items packaged at Rocky Flats Environmental Technology Site (RFETS). Many of these packages were later found to contain excess moisture. Savannah River National Laboratory (SRNL) testing has resulted in a better understanding of the relationship between the fiberboard moisture level and compaction of the fiberboard under storage conditions and during transport. In laboratory testing, the higher moisture content has been shown to correspond to higher total compaction of fiberboard material and compaction rate. The fiberboard height is reduced by compression of the layers. This change is observed directly in the axial gap between the flange and the air shield. The axial gap measurement is made during the pre-use inspection or during the annual recertification process and is a screening measurement for changes in the fiberboard.

Hackney, E. R.; Dougherty, W. L.; Dunn, K. A.; Stefek, T. M

2013-08-01T23:59:59.000Z

356

Final report for NIF chamber dynamics studies, final rept (May 1997), Subcontract No. B291847  

SciTech Connect (OSTI)

The National Ignition Facility (NIF), a 1.8 MJ, 192 laser beam facility, will have anticipated fusion yields of up to 20 MJ from D-T pellets encased in a gold hohlraum target. The energy emitted from the target in the form of x rays, neutrons, target debris kinetic energy, and target shrapnel will be contained in a 5 m. radius spherical target chamber. Various diagnostics will be stationed around the target at varying distances from the target. During each shot, the target will emit x rays that will vaporize nearby target facing surfaces including those of the diagnostics, the target positioner, and other chamber structures. This ablated vapor will be transported throughout the chamber, and will eventually condense and deposit on surfaces in the chamber, including the final optics debris shields. The research at the University of California at Berkeley relates primarily to the NIF chamber dynamics. The key design issues are the ablation of the chamber structures, transport of the vapor through the chamber and the condensation or deposition processes of those vaporized materials. An understanding of these processes is essential in developing a concept for protecting the final optics debris shields from an excessive coating (> 10 {Angstrom}) of target debris and ablated material, thereby prolonging their lifetime between change- outs. At Berkeley, we have studied the physical issues of the ablation process and the effects of varying materials, the condensation process of the vaporized material, and design schemes that can lower the threat posed to the debris shields by these processes. In addition to the work described briefly above, we performed extensive analysis of the target-chamber thermal response to in- chamber CO{sub 2} Cleaning and of work performed to model the behavior of silica vapor. The work completed this year has been published in several papers and a dissertation [1-6]. This report provides a summary of the work completed this year, as well as copies fo presentation materials that have not been published elsewhere. In particular, the Appendix contains copies of presentations made on CO{sub 2} cleaning that are not available elsewhere.

Peterson, P.F.; Jin, H.; Scott, J.M. [University of California, Berkeley (United States)

1997-07-01T23:59:59.000Z

357

Parity-Violating Electron Deuteron Scattering and the Proton's Neutral Weak Axial Vector Form Factor  

SciTech Connect (OSTI)

We report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at backward angles at Q2 = 0.038 (GeV/c)2. This quantity provides a determination of the neutral weak axial vector form factor of the nucleon, which can potentially receive large electroweak corrections. The measured asymmetry A = z3.51±0.57 (stat)±0.58 (syst) ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at Q2 = 0.091 (GeV/c)2, which are also consistent with theoretical predictions.

Ito, Takeyasu; Averett, Todd; Barkhuff, David; Batigne, Guillaume; Beck, Douglas; Beise, Elizabeth; Blake, A.; Breuer, Herbert; Carr, Robert; Clasie, Benjamin; Covrig, Silviu; Danagoulian, Areg; Dodson, George; Dow, Karen; Dutta, Dipangkar; Farkhondeh, Manouchehr; Filippone, Bradley; FRANKLIN, W.; Furget, Christophe; Gao, Haiyan; Gao, Juncai; Gustafsson, Kenneth; Hannelius, Lars; Hasty, R.; Allen, Alice; Herda, M.C.; Jones, CE; King, Paul; Korsch, Wolfgang; Kowalski, Stanley; Kox, Serge; Kramer, Kevin; Lee, P.; Liu, Jinghua; Martin, Jeffery; McKeown, Robert; Mueller, B.; Pitt, Mark; Plaster, Bradley; Quemener, Gilles; Real, Jean-Sebastien; Ritter, J.; Roche, Julie; Savu, V.; Schiavilla, Rocco; Seely, Charles; Spayde, Damon; Suleiman, Riad; Taylor, S.; Tieulent, Raphael; Tipton, Bryan; Tsentalovich, E.; Wells, Steven; Yang, Bin; Yuan, Jing; Yun, Junho; Zwart, Townsend

2004-03-01T23:59:59.000Z

358

The effect of adding axial freedom to the blades of a two bladed helicopter rotor  

E-Print Network [OSTI]

cire used on the rotor, the link nas all the blades attacned to it, and tne "teeter-totter" nin!;e rr&rst be excnanSe&! for a univ& rsal point, preferably of tne con: t-rrrt velocitv tyi e. Tne a?de&& blades snoula rrnve a stabilizin;, . irif i...THE Epr'ECT OZ ADDIRQ AX' AL RREEDO?l TO THE Bl ADRS QF A TWO BLADED HELICOPTER ROTOR A Thesis Frank Robert Oradat, Jr. Approveo as to style and content by: (Cnair. san of Co xttee) (liead of Dep tment) May I955 THE EPPECT OP ADDING AXIAL...

Oradat, Frank Robert

1953-01-01T23:59:59.000Z

359

Statistical and risk analysis for the measured and predicted axial response of 100 piles  

E-Print Network [OSTI]

of Committee) cu. Har y M. Coyl (Member) J rey D. Hart (Member) Donald McDonald (Head of Department) May 1986 ABSTRACT Statistical and Risk Analysis for the Measured and Predicted Axial Response of 100 Piles (December 1985) Dario Perdomo, B. S... encouragement and financial support. Sincere thanks are expressed to Dr. Jean-Louis Briaud and Nr. Larry Tucker i'or their guidance and advice throughout the course of this research. The assistance of Dr. Harry Coyle and Dr. Jeffrey Hart are also...

Perdomo, Dario

1986-01-01T23:59:59.000Z

360

Determination of the Axial-Vector Weak Coupling Constant with Ultracold Neutrons  

E-Print Network [OSTI]

A precise measurement of the neutron decay $\\beta$-asymmetry $A_0$ has been carried out using polarized ultracold neutrons (UCN) from the pulsed spallation UCN source at the Los Alamos Neutron Science Center (LANSCE). Combining data obtained in 2008 and 2009, we report $A_0 = -0.11966 \\pm 0.00089_{-0.00140}^{+0.00123}$, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon $g_A/g_V = -1.27590_{-0.00445}^{+0.00409}$.

UCNA Collaboration; J. Liu; M. P. Mendenhall; A. T. Holley; H. O. Back; T. J. Bowles; L. J. Broussard; R. Carr; S. Clayton; S. Currie; B. W. Filippone; A. Garcia; P. Geltenbort; K. P. Hickerson; J. Hoagland; G. E. Hogan; B. Hona; T. M. Ito; C. -Y. Liu; M. Makela; R. R. Mammei; J. W. Martin; D. Melconian; C. L. Morris; R. W. Pattie Jr.; A. Perez Galvan; M. L. Pitt; B. Plaster; J. C. Ramsey; R. Rios; R. Russell; A. Saunders; S. J. Seestrom; W. E. Sondheim; E. Tatar; R. B. Vogelaar; B. VornDick; C. Wrede; H. Yan; A. R. Young

2010-09-25T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Determination of the Axial-Vector Weak Coupling Constant with Polarized Ultracold Neutrons  

E-Print Network [OSTI]

A precise measurement of the neutron decay $\\beta$-asymmetry $A_0$ has been carried out using polarized ultracold neutrons (UCN) from the pulsed spallation UCN source at the Los Alamos Neutron Science Center (LANSCE). Combining data obtained in 2008 and 2009, we report $A_0 = -0.11966 \\pm 0.00089 _{-0.00140}^{+0.00123}$, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon $g_A/g_V = -1.27590 _{-0.00445}^{+0.00409}$.

Liu, J; Holley, A T; Back, H O; Bowles, T J; Broussard, L J; Carr, R; Clayton, S; Currie, S; Filippone, B W; Garcia, A; Geltenbort, P; Hickerson, K P; Hoagland, J; Hogan, G E; Hona, B; Ito, T M; Liu, C -Y; Makela, M; Mammei, R R; Martin, J W; Melconian, D; Morris, C L; Pattie, R W; Galvan, A Perez; Pitt, M L; Plaster, B; Ramsey, J C; Rios, R; Russell, R; Saunders, A; Seestrom, S; Sondheim, W E; Tatar, E; Vogelaar, R B; VornDick, B; Wrede, C; Yan, H; Young, A R

2010-01-01T23:59:59.000Z

362

Spatiotemporal evolution of ponderomotive electron heating in axially inhomogeneous collisionless plasma  

SciTech Connect (OSTI)

We investigate the spatiotemporal focusing dynamics of a Gaussian laser pulse in preformed collisionless plasma subjected to an axial nonuniformity in the plasma density. In order to follow up the pulse dynamics, a nonlinear Schrödinger wave equation characterizing the beam spot size in space and time frame has been derived and solved numerically to investigate the propagation characteristics as the pulse advances in the plasma. The effect of inhomogeneity on focusing length and ponderomotive electron heating have been analyzed and illustrated graphically. It is seen that ponderomotive heating is quite sensitive to the inhomogeneity parameters and the energy gain by electrons can be optimized by suitable choice of parameters.

Mishra, S. K. [Institute for Plasma Research (IPR), Gandhinagar (India)] [Institute for Plasma Research (IPR), Gandhinagar (India); Sharma, A. [Institute of Physics, University of Pecs, Pecs 7624 (Hungary)] [Institute of Physics, University of Pecs, Pecs 7624 (Hungary)

2013-07-15T23:59:59.000Z

363

Axial SiGe Heteronanowire Tunneling Field-Effect Transistors. | EMSL  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-Series to someone byDearTechnicalAwards recognize outstandingAwards SmallAxial

364

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

SciTech Connect (OSTI)

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

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

2014-03-15T23:59:59.000Z

365

April 10, 2002 A. R. Raffray, et al., Dynamic Chamber Armor Behavior in IFE and MFE 1 Dynamic Chamber Armor Behavior in IFE and MFE  

E-Print Network [OSTI]

Limiter 0.5 (~8 for ~100s) 30000 (5000) Baffle 3 3000-10000 Divertor target ~10 3000-10000 #12;April 10/m2 Affected area 5-10 m2 A few m2 ~10 m2 Chamber wall (R~5-10 m) Location Surface (near divertor ms ~ 1-3 µs Max. Temperature Melting/ sublimation Melting/ sublimation Melting/ sublimation ~ 2000-3000

Raffray, A. René

366

The High Momentum Spectrometer Drift Chambers in Hall C at CEBAF  

SciTech Connect (OSTI)

The mutiwire drift chambers to be used in the High Momentum Spectrometer (HMS) at the Continuous Electron Beam Accelerator Facility (CEBAF) have been designed and constructed, and recently employed in initial data-taking runs.These chambers are used to reconstruct scattered charged particle momenta in the HMS using 12C and BeO2 targets for incident electron energies up to 2.2 GeV.Offline analysis of the data indicate that these drift chambers have spatial resolution (per plane) of about 115 mu-m (sigma) in rates approaching a KHz/wire/mm.It is expected that this performance will improve at higher momenta where multiple scattering contributions are smaller.

Vulcan, William; Kross, Brian; Beaufait, Joseph; Baker, O.; Carlini, Roger; Majewski, Stanislaw; Johnson, A.; McCauley, A.; Niculescu, Gabriel; Niculescu, Maria-Ioana; Cha, Jinseok; Shin, Taeksu; Naing, Win; Danagoulian, Samuel

1995-12-01T23:59:59.000Z

367

Effects of outgassing of loader chamber walls on hydriding of thin films for commercial applications  

SciTech Connect (OSTI)

An important aspect of understanding industrial processing is to know the characteristics of the materials used in such processes. A study was performed to determine the effects of hydriding chamber material on the degree of hydriding for the commercial production of thin film hydride targets for various research universities, commercial companies, and government national laboratories. The goal was to increase the degree of hydriding of various thin film hydrides and to study the vacuum environment during air-exposure hydriding. For this purpose, dynamic residual gas analysis during deuterium gas hydride processing was utilized with erbium thin films, employing a special set-up for direct dynamic hydride gas sampling during processing at elevated temperature and full loading gas pressure. Complete process data for (1) a copper–(1.83?wt.?%)beryllium wet hydrogen fired passivated (600?°C–1?h) externally heated pipe hydriding chamber are reported. Dynamic residual gas analysis comparisons during hydriding are presented for hydriding chambers made from (2) alumina (99.8 wt.?%), (3) copper (with an interior aluminum coating ?10 k Å thick, and (4) for a stainless-steel air-fired passivated (900?°C–1?h) chamber. Dynamic data with deuterium gas in the chamber at the hydriding temperature (450?°C) showed the presence and growth of water vapor (D{sub 2}O) and related mixed ion species(H{sub 2}O{sup +}, HDO{sup +}, D{sub 2}O{sup +}, and OD{sup +}) from hydrogen isotope exchange reactions during the 1?h process time. Peaks at mass-to-charge ratios (i.e., m/e) of 12(C{sup +}), 16(CD{sub 2}{sup +}), 17(CHD{sub 2}{sup +}), and 18(CD{sub 3}{sup +}, OD{sup +}) increased for approximately the first half hour of a 1?h hydriding process and then approach steady state. Mass-to-charge peaks at 19(HDO{sup +}) and 20(D{sub 2}O{sup +}) continue to increase throughout the process cycle. Using the m/e?=?20 (D{sub 2}O{sup +}) peak intensity from chamber (1)–Cu(1.83 wt.?%)Be as a standard, the peak intensity from chamber (4)—stainless-steel (air-fired) was 7.1× higher, indicating that the surface of stainless-steel had a larger concentration of reactive oxygen and/or water than hydrogen. The (D{sub 2}O{sup +}) peak intensity from chamber (3)—Cu (interior Al coating) was 1.55× larger and chamber (2)—alumina(99.8%) was 1.33× higher than Cu(1.83 wt.?%)Be. Thus copper–(1.83 wt.?%)beryllium was the best hydriding chamber material studied followed closely by the alumina (99.8 wt.?%) chamber. Gas take-up by Er occluder targets processed in Cu(1.83?wt.?%)Be hydriding chambers (i.e., gas/metal atomic ratios) correlate with the dynamic RGA data.

Provo, James L., E-mail: jlprovo@verizon.net [Consultant, J.L. Provo Consulting, Trinity, Florida 34655-7179 (United States)

2014-07-01T23:59:59.000Z

368

Front-end Electronics Test for the LHCb Muon Wire Chambers  

E-Print Network [OSTI]

This document describes the apparatus and procedures implemented to test Multi Wire Proportional Chambers (MWPC) after front-end assembly for the LHCb Muon Detector. Results of measurements of key noise parameters are also described. Given a fully equipped chamber, this system is able to diagnose every channel performing an analysis of front-end output drivers’ response and noise rate versus threshold. Besides, it allows to assess if the noise rate at the experiment threshold region is within appropriate limits. Aiming at an automatic, fast and user-friendly system for mass production tests of MWPC, the project has foreseen as well electronic identification of every chamber and front-end board, and data archiving in such a way to make it available to the Experiment Control System (ECS) while in operation.

Nobrega, R; Carboni, G; Massafferri, A; Santovetti, E

2007-01-01T23:59:59.000Z

369

Test Facility for Full-Equipped Chambers for the LHCb Muon Detector  

E-Print Network [OSTI]

The LHCb Muon System is made up by more than 1300 chambers of 20 different types, resulting in more than 120k readout channels. In order to guarantee high-quality performance during the experiment it is of crucial importance to get a complete knowledge of the fully equipped detector functionalities.A complete test system was built and a C++ ROOT software was developed to allow carring out a variety of studies on the many LHCb Muon chambers. Such system provides full control of the frontend, the high-voltage and the acquisition electronics and makes available a number of procedures to study the chambersâ?? performance. It was used for studies and a quality control on the chambers before and during the final positioning on the detector. In this note an overview of the hardware setup and of the software will be given. Results of measurements related to front-end channels characteristics will be presented.

Nóbrega, Rafael

2007-01-01T23:59:59.000Z

370

Clean measurements of the nucleon axial-vector and free-neutron magnetic form factors  

E-Print Network [OSTI]

We discuss the feasibility of a weak charged current experiment using a low energy electron beam. A first goal is to measure the Q^2 dependence of the axial-vector form factor g_a(Q^2). It can be measured model-independently and as robustly as for electromagnetic form factors from typical electron scattering experiments, in contrast to the methods used so far to measure g_a(Q^2). If g_a(Q^2) follows a dipole form, the axial mass can be extracted with a better accuracy than the world data altogether. The most important detection equipment would be a segmented neutron detector with good momentum and angular resolution that is symmetric about the beam direction, and covers a moderate angular range. A high intensity beam (100 uA) is necessary. Beam polarization is highly desirable as it provides a clean measurement of the backgrounds. Beam energies between 70 and 110 MeV are ideal. This range would provide a Q^2 mapping of g_a between 0.01

Alexandre Deur

2014-07-21T23:59:59.000Z

371

Measuring the axial form factor of {sup 3}He using weak capture of polarized electrons  

SciTech Connect (OSTI)

A low energy, high intensity polarized electron beam could enable the extraction of the A=3 weak axial form factors F{sub A} using the reaction ?e+{sup 3}He?{sup 3}H+?. These form factors have never been measured before. We discuss the feasibility of such an experiment using a small toroidal magnet and a radial low energy recoil detector to tag the recoil tritons. A moderately high intensity polarized electron beam (>500 ?A) with beam energies between 50 - 150 MeV is necessary for the cross section measurement and to provides a free clean measurement of the background. Moreover, in addition to the cross section, by measuring the electron spin and recoil triton correlation coefficient it may be possible to search for second class currents and to extract the ratio of the axial to the vector form factor of the nucleon. Such novel electron scattering based measurements would have a completely different set of systematic uncertainties compared to polarized neutron beta decay, neutrino scattering and muon capture experiments which are typically used to extract the weak form-factors.

Dutta, D. [Mississippi State University, Mississippi State, MS 39762 (United States)

2013-11-07T23:59:59.000Z

372

Broken axial symmetry as essential feature to predict radiative capture in heavy nuclei  

E-Print Network [OSTI]

Cross sections for neutron capture in the range of unresolved resonances are predicted for more than 140 spin-0 target nuclei with A > 50. Allowing the breaking of spherical and axial symmetry in nearly all these nuclei a combined parameterization for both, level density and photon strength is obtained which employs a surprisingly small number of parameters only. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians. They are based on theoretical predictions for the A-dependence of pole energies and spreading widths and add up to the TRK sum rule. For the small spins reached by capture resonance spacings are well described by a level density parameter close to the nuclear matter value; a significant collective enhancement is apparent due to the deviation from axial symmetry. Reliable predictions for compound nuclear reactions also outside the valley of stability (as important for nuclear astrophysics and for the transmutation of nuclear waste) are expected to result from the global parameterization presented.

Eckart Grosse; Arnd R. Junghans; Ralph Massarczyk

2015-01-14T23:59:59.000Z

373

Clean measurements of the nucleon axial-vector and free-neutron magnetic form factors  

SciTech Connect (OSTI)

We discuss the feasibility of a weak charged current experiment using a low energy electron beam. A first goal is to measure the Q^2 dependence of the axial-vector form factor g_a(Q^2). It can be measured model-independently and as robustly as for electromagnetic form factors from typical electron scattering experiments, in contrast to the methods used so far to measure g_a(Q^2). If g_a(Q^2) follows a dipole form, the axial mass can be extracted with a better accuracy than the world data altogether. The most important detection equipment would be a segmented neutron detector with good momentum and angular resolution that is symmetric about the beam direction, and covers a moderate angular range. A high intensity beam (100 uA) is necessary. Beam polarization is highly desirable as it provides a clean measurement of the backgrounds. Beam energies between 70 and 110 MeV are ideal. This range would provide a Q^2 mapping of g_a between 0.01

Deur, Alexandre P. [JLAB

2013-11-01T23:59:59.000Z

374

Fracture analysis of axially cracked pressure tube of pressurized heavy water reactor  

SciTech Connect (OSTI)

Three Dimensional (313) finite element elastic plastic fracture analysis was done for through wall axially cracked thin pressure tubes of 220 MWe Indian Pressurized Heavy Water Reactor. The analysis was done for Zr-2 and Zr-2.5Nb pressure tubes operating at 300{degrees}C and subjected to 9.5 Mpa internal pressure. Critical crack length was determined based on tearing instability concept. The analysis included the effect of crack face pressure due to the leaking fluid from tube. This effect was found to be significant for pressure tubes. The available formulae for calculating J (for axially cracked tubes) do not take into account the effect of crack face pressure. 3D finite element analysis also gives insight into variation of J across the thickness of pressure tube. It was observed that J is highest at the mid-surface of tube. The results have been presented in the form of across the thickness average J value and a peak factor on J. Peak factor on J is ratio of J at mid surface to average J value. Crack opening area for different cracked lengths was calculated from finite element results. The fracture assessment of pressure tubes was also done using Central Electricity Generating Board R-6 method. Ductile tearing was considered.

Krishnan, S.; Bhasin, V.; Mahajan, S.C. [Bhabha Atomic Research Centre, Bombay (India)] [and others

1997-04-01T23:59:59.000Z

375

Kr II and Xe II axial velocity distribution functions in a cross-field ion source  

SciTech Connect (OSTI)

Laser induced fluorescence measurements were carried out in a cross-field ion source to examine the behaviour of the axial ion velocity distribution functions (VDFs) in the expanding plasma. In the present paper, we focus on the axial VDFs of Kr II and Xe II ions. We examine the contourplots in a 1D-phase space (x,v{sub x}) representation in front of the exhaust channel and along the centerline of the ion source. The main ion beam, whose momentum corresponds to the ions that are accelerated through the whole potential drop, is observed. A secondary structure reveals the ions coming from the opposite side of the channel. We show that the formation of the neutralized ion flow is governed by the annular geometry. The assumption of a collisionless shock or a double layer due to supersonic beam interaction is not necessary. A non-negligible fraction of slow ions originates in local ionization or charge-exchange collision events between ions of the expanding plasma and atoms of the background residual gas. Slow ions that are produced near the centerline in the vicinity of the exit plane are accelerated toward the source body with a negative velocity leading to a high sputtering of front face. On the contrary, the ions that are produced in the vicinity of the channel exit plane are partially accelerated by the extended electric field.

Lejeune, A.; Bourgeois, G.; Mazouffre, S. [ICARE, CNRS, 1C Avenue de la Recherche Scientifique, 45071 Orlans Cedex 2 (France)

2012-07-15T23:59:59.000Z

376

Broken axial symmetry as essential feature to predict radiative capture in heavy nuclei  

E-Print Network [OSTI]

Cross sections for neutron capture in the range of unresolved resonances are predicted for more than 140 spin-0 target nuclei with A > 50. Allowing the breaking of spherical and axial symmetry in nearly all these nuclei a combined parameterization for both, level density and photon strength is obtained which employs a surprisingly small number of parameters only. The strength functions used are based on a global fit to IVGDR shapes by the sum of three Lorentzians. They are based on theoretical predictions for the A-dependence of pole energies and spreading widths and add up to the TRK sum rule. For the small spins reached by capture resonance spacings are well described by a level density parameter close to the nuclear matter value; a significant collective enhancement is apparent due to the deviation from axial symmetry. Reliable predictions for compound nuclear reactions also outside the valley of stability (as important for nuclear astrophysics and for the transmutation of nuclear waste) are expected to re...

Grosse, Eckart; Massarczyk, Ralph

2014-01-01T23:59:59.000Z

377

A two-dimensional (azimuthal-axial) particle-in-cell model of a Hall thruster  

SciTech Connect (OSTI)

We have developed a two-dimensional Particle-In-Cell model in the azimuthal and axial directions of the Hall thruster. A scaling method that consists to work at a lower plasma density to overcome constraints on time-step and grid-spacing is used. Calculations are able to reproduce the breathing mode due to a periodic depletion of neutral atoms without the introduction of a supplementary anomalous mechanism, as in fluid and hybrid models. Results show that during the increase of the discharge current, an electron-cyclotron drift instability (frequency in the range of MHz and wave number on the order of 3000 rad s{sup ?1}) is formed in the region of the negative gradient of magnetic field. During the current decrease, an axial electric wave propagates from the channel toward the exhaust (whose frequency is on the order of 400?kHz) leading to a broadening of the ion energy distribution function. A discussion about the influence of the scaling method on the calculation results is also proposed.

Coche, P.; Garrigues, L., E-mail: laurent.garrigues@laplace.univ-tlse.fr [LAPLACE (Laboratoire Plasma et Conversion d'Energie), Université de Toulouse, UPS, INPT Toulouse 118, route de Narbonne, F-31062 Toulouse cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France)

2014-02-15T23:59:59.000Z

378

Construction and test of high precision drift-tube (sMDT) chambers for the ATLAS muon spectrometer  

E-Print Network [OSTI]

For the upgrade of the ATLAS muon spectrometer in March 2014 new muon tracking chambers (sMDT) with drift-tubes of 15 mm diameter, half of the value of the standard ATLAS Monitored Drift-Tubes (MDT) chambers, and 10~$\\mu$m positioning accuracy of the sense wires have been constructed. The new chambers are designed to be fully compatible with the present ATLAS services but, with respect to the previously installed ATLAS MDT chambers, they are assembled in a more compact geometry and they deploy two additional tube layers that provide redundant rack information. The chambers are composed of 8 layers of in total 624 aluminium drift-tubes. The assembly of a chamber is completed within a week. A semi-automatized production line is used for the assembly of the drift-tubes prior to the chamber assembly. The production procedures and the quality control tests of the single components and of the complete chambers will be discussed. The wire position in the completed chambers have been measured by using a coordinate measuring machine.

Sebastian Nowak; Oliver Korner; Hubert Kroha; Philipp Schwegler; Federico Sforza

2014-07-01T23:59:59.000Z

379

Multi-gap Resistive Plate Chambers as a Time-of-Flight System for the PHENIX Experiment  

SciTech Connect (OSTI)

In this project a Time-of-Flight detector based on multi-gap resistive plate chambers was built and installed for the PHENIX experiment at RHIC.

Velkovska, Julia [Vanderbilt University] [Vanderbilt University

2013-12-08T23:59:59.000Z

380

A study of the response of a gas ionization chamber to different sources of ionizing radiation  

E-Print Network [OSTI]

; is the effective average energy to produce one pair (for values, see Table I). Charged particles produced by ionization lose their energy rather quickly in multiple collisions with the gas molecules and assume the thermal energy distribution of the gas. When... of aluminum extrusion ionization chambers to this kind of radiation was investigated. Also, since the TAMU counter is a prototype (1 in x 7in x 7in) of the chambers installed at CDF (1 in x 84in x 84in), the pad-to-wire signal ratio had to be measured...

Zamble?-Die?guez, Filiberto Edmundo

1988-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

An atomic layer deposition chamber for in situ x-ray diffraction and scattering analysis  

SciTech Connect (OSTI)

The crystal structure of thin films grown by atomic layer deposition (ALD) will determine important performance properties such as conductivity, breakdown voltage, and catalytic activity. We report the design of an atomic layer deposition chamber for in situ x-ray analysis that can be used to monitor changes to the crystal structural during ALD. The application of the chamber is demonstrated for Pt ALD on amorphous SiO{sub 2} and SrTiO{sub 3} (001) using synchrotron-based high resolution x-ray diffraction, grazing incidence x-ray diffraction, and grazing incidence small angle scattering.

Geyer, Scott M.; Methaapanon, Rungthiwa; Kim, Woo-Hee; Bent, Stacey F., E-mail: sbent@stanford.edu [Department of Chemical Engineering, Stanford University, Stanford, California 94305 (United States); Johnson, Richard W. [Department of Materials Science and Engineering, Stanford University, Stanford, California 94305 (United States); Van Campen, Douglas G.; Metha, Apurva [SLAC National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Menlo Park, California 94025 (United States)

2014-05-15T23:59:59.000Z

382

Wafer chamber having a gas curtain for extreme-UV lithography  

DOE Patents [OSTI]

An EUVL device includes a wafer chamber that is separated from the upstream optics by a barrier having an aperture that is permeable to the inert gas. Maintaining an inert gas curtain in the proximity of a wafer positioned in a chamber of an extreme ultraviolet lithography device can effectively prevent contaminants from reaching the optics in an extreme ultraviolet photolithography device even though solid window filters are not employed between the source of reflected radiation, e.g., the camera, and the wafer. The inert gas removes the contaminants by entrainment.

Kanouff, Michael P. (Livermore, CA); Ray-Chaudhuri, Avijit K. (Livermore, CA)

2001-01-01T23:59:59.000Z

383

Selection of dimensions for the accelerating chamber of a betatron with extraction of an electron beam  

SciTech Connect (OSTI)

The authors discuss the results of refinement of the dynamics of particles of a beam extracted from a betatron, a refinement which has made it possible to select the main dimensions of the accelerating chamber. Expressions are obtained which make it possible to determine the chamber dimensions and the profile of the extraction window from the distribution of the magnetic field of the betatron. It is shown that proper selection of the dimensions will increase the dose rate at the exit from the magnetic core of the accelerator.

Chakhlov, V.L.; Kashovskii, V.V.; Pushin, V.S.

1985-09-01T23:59:59.000Z

384

Calibration and performance of a secondary emission chamber as a beam intensity monitor  

SciTech Connect (OSTI)

We report on a study of the behavior of a secondary emission chamber (SEC). We show the dependence of the SEC signal on the charge and velocity of the primary beam for beams of protons, and heavy ions including Helium, Neon, Chlorine and Iron. We fill the SEC with a selection of different gases including Hydrogen, Helium, Nitrogen, Argon, and air, studying the SEC response when it is acting as an ion chamber. We also investigate the behavior of the SEC at intermediate pressures between 10{sup -8} torr and atmospheric pressure. The SEC uses thin conducting foils as the source and collector of electrons in a vacuum chamber. When charged particles traverse the vacuum chamber, they pass through a series of thin conducting foils, alternating anode and cathode. Ionization produced in the cathode foils travels across the intervening gap due to an applied high voltage and is collected on the anode foils. Electron production is very inefficient because most of the ionization in the foils remains trapped within the foil due to the short range of most delta-rays and the work function of the foil. It is this inefficiency that allows the SEC to operate at high dose rates and short pulse duration where the standard ion chambers cannot function reliably. The SEC was placed in the NSRL ion beam to receive a variety of heavy ion beams under different beam conditions. We used these ion beams to study the response of the SEC to different species of heavy ion, comparing with proton beams. We studied the response to beam of different energies, and as a function of different counting rate. We compared the behaviour of the SEC when operating under positive and negative high voltage. The SEC can operate as an ion chamber if it is filled with gas. We measured the response of the SEC when filled with a variety of gases, from Hydrogen to Helium, Nitrogen, Argon and air. The performance of the SEC as an ion chamber is compared with the standard NSRL ion chamber, QC3. By evacuating the SEC and filling it with Nitrogen through an adjustable leak valve, we were able to measure the response of the SEC to beam as a function of gas pressure. Many interesting features of the SEC were revealed in these tests.

Sivertz, M.; Chiang, I-H,; Rusek, A.

2011-03-28T23:59:59.000Z

385

IFE thick liquid wall chamber dynamics: Governing mechanisms andmodeling and experimental capabilities  

SciTech Connect (OSTI)

For thick liquid wall concepts, it is important to understand the different mechanisms affecting the chamber dynamics and the state of the chamber prior to each shot a compared with requirements from the driver and target. These include ablation mechanisms, vapor transport and control, possible aerosol formation, as well as protective jet behavior. This paper was motivated by a town meeting on this subject which helped identify the major issues, assess the latest results, review the capabilities of existing modeling and experimental facilities with respect to addressing remaining issues, and helping guide future analysis and R&D efforts; the paper covers these exact points.

Raffray, A.R.; Meier, W.; Abdel-Khalik, S.; Bonazza, R.; Calderoni, P.; Debonnel, C.S.; Dragojlovic, Z.; El-Guebaly, L.; Haynes,D.; Latkowski, J.; Olson, C.; Peterson, P.F.; Reyes, S.; Sharpe, P.; Tillack, M.S.; Zaghloul, M.

2005-01-24T23:59:59.000Z

386

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

E-Print Network [OSTI]

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

Toomey, Doug

387

Natural Circulation and Linear Stability Analysis for Liquid-Metal Reactors with the Effect of Fluid Axial Conduction  

SciTech Connect (OSTI)

The effect of fluid axial thermal conduction on one-dimensional liquid metal natural circulation and its linear stability was performed through nondimensional analysis, steady-state assessment, and linear perturbation evaluation. The Nyquist criterion and a root-search method were employed to find the linear stability boundary of both forward and backward circulations. The study provided a relatively complete analysis method for one-dimensional natural circulation problems with the consideration of fluid axial heat conduction. The results suggest that fluid axial heat conduction in a natural circulation loop should be considered only when the modified Peclet number is {approx}1 or less, which is significantly smaller than the practical value of a lead liquid metal-cooled reactor.

Piyush Sabharwall; Qiao Wu; James J. Sienicki

2012-06-01T23:59:59.000Z

388

Plate Fin Heat Exchanger Model with Axial Conduction and Variable Properties  

SciTech Connect (OSTI)

Future superconducting radio frequency (SRF) cavities, as part of Project X at Fermilab, will be cooled to superfluid helium temperatures by a cryogenic distribution system supplying cold supercritical helium. To reduce vapor fraction during the final Joule-Thomson (J-T) expansion into the superfluid helium cooling bath, counter-flow, plate-fin heat exchangers will be utilized. Due to their compact size and ease of fabrication, plate-fin heat exchangers are an effective option. However, the design of compact and high-effectiveness cryogenic heat exchangers operating at liquid helium temperatures requires consideration of axial heat conduction along the direction of flow, in addition to variable fluid properties. Here we present a numerical model that includes the effects of axial conduction and variable properties for a plate fin heat exchanger. The model is used to guide design decisions on heat exchanger material choice and geometry. In addition, the J-T expansion process is modeled with the heat exchanger to analyze the effect of heat load and cryogenic supply parameters. A numerical model that includes the effects of axial conduction and variable properties for a plate fin heat exchanger was developed and the effect of various design parameters on overall heat exchanger size was investigated. It was found that highly conductive metals should be avoided in the design of compact JT heat exchangers. For the geometry considered, the optimal conductivity is around 3.5 W/m-K and can range from 0.3-10 W/m-K without a large loss in performance. The model was implemented with an isenthalpic expansion process. Increasing the cold side inlet temperature from 2K to 2.2 K decreased the liquid fraction from 0.856 to 0.839 which corresponds to a 0.12 g/s increase in supercritical helium supply needed to maintain liquid level in the cooling bath. Lastly, it was found that the effectiveness increased when the heat load was below the design value. Therefore, the heat exchanger should be sized on the high end of the required heat load.

Hansen, B.J.; White, M.J.; Klebaner, A.; /Fermilab

2011-06-10T23:59:59.000Z

389

Effect of nitrate on the performance of single chamber air cathode microbial fuel cells  

E-Print Network [OSTI]

Effect of nitrate on the performance of single chamber air cathode microbial fuel cells Chontisa Accepted 26 August 2008 Published online 11 September 2008 Keywords: Microbial fuel cell Denitrification microbial fuel cells (MFCs) has drawn much attention recently as a new approach of waste- water treatment

Tullos, Desiree

390

Assessment of the high temperature fission chamber technology for the French fast reactor program  

SciTech Connect (OSTI)

High temperature fission chambers are key instruments for the control and protection of the sodium-cooled fast reactor. First, the developments of those neutron detectors, which are carried out either in France or abroad are reviewed. Second, the French realizations are assessed with the use of the technology readiness levels in order to identify tracks of improvement. (authors)

Jammes, C.; Filliatre, P.; Geslot, B.; Domenech, T.; Normand, S. [Commissariat a l'Energie Atomique, CEA (France)

2011-07-01T23:59:59.000Z

391

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

E-Print Network [OSTI]

-ion, laser and Z-pinch drivers. A variety of chamber concepts are being investigated including dry- wall (currently favored for laser IFE), wetted-wall (applicable to both laser and ion drivers), and thick- liquid-wall (favored by heavy ion and z-pinch drivers). Recent progress and remaining challenges in developing IFE

Najmabadi, Farrokh

392

Calculating Radiative Heat Transfer in an Axisymmetric Closed Chamber: An Application  

E-Print Network [OSTI]

Calculating Radiative Heat Transfer in an Axisymmetric Closed Chamber: An Application to Crystal University of New York at Stony Brook Stony Brook N.Y. 11794 ABSTRACT Radiative heat transfer plays simulating radiative heat transfer in the crystal and in the region above the melt containing gas under

New York at Stoney Brook, State University of

393

Neutronics Assessment of Blanket Options for the HAPL Laser Inertial Fusion Energy Chamber  

E-Print Network [OSTI]

-cooled lithium blanket, a helium-cooled solid breeder blanket, and a dual-coolant lithium lead blanket of the reference blanket. Keywords-Laser fusion; lithium blanket; solid breeder; lithium lead; tritium breedingNeutronics Assessment of Blanket Options for the HAPL Laser Inertial Fusion Energy Chamber M

Raffray, A. René

394

Agricultural and Forest Meteorology 123 (2004) 159176 Comparison of different chamber techniques for  

E-Print Network [OSTI]

Agricultural and Forest Meteorology 123 (2004) 159­176 Comparison of different chamber techniques �strengl, Waldemar Zieglerm, Peter Anthonim, Anders Lindrothn, Pertti Haria a Department of Forest Ecology Sciences and Energy Research, Weizmann Institute of Science, P.O. Box 26, Rehovot 76100, Israel h

Yakir, Dan

395

October 24, 2001 1. Remaining Action Items on Dry Chamber Wall  

E-Print Network [OSTI]

of Simplified Assumption Used to Estimate Temporal Distribution of Energy Depositions Photons Debris Ions Time10ns 0.2µs 1µs 2.5µs Fast Ions Energy Deposition Temporal Distribution of Energy Depositions from Ions for Direct Drive Spectra and Chamber Radius of 6.5 m Simplified Temporal Distribution of Energy Depositions

Raffray, A. René

396

Short Communication Electricity generation from fermented primary sludge using single-chamber  

E-Print Network [OSTI]

Short Communication Electricity generation from fermented primary sludge using single-chamber air Keywords: Microbial fuel cell Electricity Primary sludge Fermentation Power density a b s t r a c t Single sludge. Fermentation (30 °C, 9 days) decreased total suspended solids (26.1­16.5 g/L), volatile suspended

397

First limit from a surface run of a 10 liter Dark Matter Time Projection Chamber  

E-Print Network [OSTI]

A 10 liter prototype Dark Matter Time Projection Chamber (DMTPC) is operated on the surface of the earth at 75 Torr using carbon-tetrafluoride (CF4) as a target material to obtain a 24.57 gram-day exposure. A limit is set ...

Caldwell, Thomas S., Jr

2009-01-01T23:59:59.000Z

398

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

E-Print Network [OSTI]

%. For propane/air combustion, the stability limits ranged from ~ 0.25 to 2 for the 124 mm3 combustor. Methane of a small combustor not only makes the heat generated from the combustion process hard to keep pace1 Combustion in Meso-scale Vortex Chambers Ming-hsun Wu* , Yanxing Wang, Vigor Yang and Richard A

Yang, Vigor

399

A model for the emergence of pillars, walls and royal chambers in termite nests  

E-Print Network [OSTI]

A model for the emergence of pillars, walls and royal chambers in termite nests Eric Bonabeau1, 31062 Toulouse Ce¨ dex, France A simple model of the emergence of pillars in termite nests by Deneubourg construction modi¢es current building conditions, we hypothesize that nest complexity can result from

Theraulaz, Guy

400

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

E-Print Network [OSTI]

(including radiation) - Turbulence effects - Laser lines and effect on final optics - Impact target injection are developing damage-resistant final optics based on grazing-incidence metal mirrors and testing them (effort, (survival and tracking) Chamber conditions (physics) Final optics (+ mirror steering) Blanket (make the most

Raffray, A. René

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

A UNIFIED MODEL FOR ION DEPOSITION AND THERMOMECHANICAL RESPONSE IN DRY WALL LASER IFE CHAMBERS  

E-Print Network [OSTI]

. INTRODUCTION In order to permit the design of an economically viable IFE power plant, we require a chamber wall reach the wall. These threats, consisting of x- rays, ions, and neutrons, can lead to wall failure associated with the IFE threats. In some cases, these inertial effects lead to stress waves that can lead

Ghoniem, Nasr M.

402

A high-resolution drift chamber for Alpha-particle position measurements  

E-Print Network [OSTI]

A drift chamber module with 5 anode wires covering an active region of 9 cm x 76 cm has been built to locate the vertical position of a-particle trajectories to within 295 mm full-width-half-maximum (FWEM) in isobutane at a pressure of 0.25 atm...

Oliver, Jon Patrick

1996-01-01T23:59:59.000Z

403

IFE THICK LIQUID WALL CHAMBER DYNAMICS: GOVERNING MECHANISMS AND MODELING AND  

E-Print Network [OSTI]

fluid! led to the HYLIFE-II design.7 The most recent integrated design based on a TLW chamber, a heavy guide future analysis and research and devel- opment efforts. KEYWORDS: inertial fusion energy, liquid to the 1970s ~Refs. 1, 2, and 3!. The first detailed conceptual design work was carried out at Lawrence

Raffray, A. René

404

Anode supported single chamber solid oxide fuel cells operating in exhaust gases of thermal engine  

E-Print Network [OSTI]

Anode supported single chamber solid oxide fuel cells operating in exhaust gases of thermal engine fuel cells are usually described as devices able to convert chemical energy into electrical energy. Conventional solid oxide fuel cells are separated into two compartments containing each electrode split

Boyer, Edmond

405

First-Forbidden beta decay Medium enhancement of the axial charge at A=16  

E-Print Network [OSTI]

Calculations are presented for four relatively strong first-forbidden $\\beta$ decays in the region A=11-16 in order to study the very large mesonic-exchange-current enhancement of the rank-zero components. The $\\mu^-$ capture on $^{16}$O is considered on the same footing. The wave functions utilized include up to 4$\\hbar\\omega$ excitations. Two-body exchange-current matrix elements are calculated as well as one-body impulse approximation matrix elements. The resultant enhancement factor that multiplies the impulse-approximation axial-charge matrix element is thereby determined by comparison to experiment to be $\\epsilon_{exp}$ = 1.61 $\\pm$ 0.03 from three $\\beta^-$ decays and $\\mu^-$ capture on $^{16}$O, which is in excellent agreement with meson-exchange calculations in the soft-pion approximation.

Warburton, E K; Brown, B A

1994-01-01T23:59:59.000Z

406

Axial strain in GaAs/InAs core-shell nanowires  

SciTech Connect (OSTI)

We study the axial strain relaxation in GaAs/InAs core-shell nanowire heterostructures grown by molecular beam epitaxy. Besides a gradual strain relaxation of the shell material, we find a significant strain in the GaAs core, increasing with shell thickness. This strain is explained by a saturation of the dislocation density at the core-shell interface. Independent measurements of core and shell lattice parameters by x-ray diffraction reveal a relaxation of 93% in a 35 nm thick InAs shell surrounding cores of 80 nm diameter. The compressive strain of -0.5% compared to bulk InAs is accompanied by a tensile strain up to 0.9% in the GaAs core.

Biermanns, Andreas; Pietsch, Ullrich [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany)] [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany); Rieger, Torsten; Gruetzmacher, Detlev; Ion Lepsa, Mihail [Peter Gruenberg Institute (PGI-9), Forschungszentrum, 52425 Juelich (Germany) [Peter Gruenberg Institute (PGI-9), Forschungszentrum, 52425 Juelich (Germany); JARA-Fundamentals of Future Information Technology, 52425 Juelich (Germany); Bussone, Genziana [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany) [Universitaet Siegen, Festkoerperphysik, 57068 Siegen (Germany); ESRF, 6 rue Jules Horowitz, BP220, F-38043 Grenoble Cedex (France)

2013-01-28T23:59:59.000Z

407

Microscopic derivation of nuclear rotation-vibration model, axially symmetric case  

E-Print Network [OSTI]

We derive from first principles the successful phenomenological hydrodynamic model of Bohr-Davydov-Faessler-Greiner for rotation-vibration motion of an axially symmetric deformed nucleus. The derivation is not limited to small oscillation amplitude, and provides microscopic expressions for the interaction operators among the rotation, vibration, and intrinsic motions, for the moment of inertia, vibration mass, and for the deformation variables. The method uses canonical transformations to collective co-ordinates, followed by a constrained variational method, with the associated constraints imposed on the wavefunction rather than on the particle co-ordinates. The approach yields three self-consistent, time-reversal invariant, cranking-type Schrodinger equations for the rotation-vibration and intrinsic motions, and a self-consistency equation. For deformed harmonic oscillator mean-field potentials, these equations are solved in closed forms for the energies, moments of inertia, quadrupole moments and transition...

Gulshani, Parviz

2015-01-01T23:59:59.000Z

408

Axial Ratio of Edge-On Spiral Galaxies as a Test For Extended Bright Radio Halos  

E-Print Network [OSTI]

We use surface brightness contour maps of nearby edge-on spiral galaxies to determine whether extended bright radio halos are common. In particular, we test a recent model of the spatial structure of the diffuse radio continuum by Subrahmanyan and Cowsik which posits that a substantial fraction of the observed high-latitude surface brightness originates from an extended Galactic halo of uniform emissivity. Measurements of the axial ratio of emission contours within a sample of normal spiral galaxies at 1500 MHz and below show no evidence for such a bright, extended radio halo. Either the Galaxy is atypical compared to nearby quiescent spirals or the bulk of the observed high-latitude emission does not originate from this type of extended halo.

Singal, J; Jones, E; Dunlap, H

2015-01-01T23:59:59.000Z

409

Shearing and geodesic axially symmetric perfect fluids that do not produce gravitational radiation  

E-Print Network [OSTI]

Using a framework based on the 1+3 formalism we carry out a study on axially and reflection symmetric perfect and geodesic fluids, looking for possible models of sources radiating gravitational waves. Therefore, the fluid should be necessarily shearing, for otherwise the magnetic part of the Weyl tensor vanishes, leading to a vanishing of the super-Poynting vector. However, for the family of perfect, geodesic fluids considered here, it appears that all possible cases reduce to conformally flat, shear--free, vorticity-free, fluids, i.e Friedmann-Roberston-Walker. The super-Poynting vector vanishes and therefore no gravitational radiation is expected to be produced. The physical meaning of the obtained result is discussed.

Herrera, L; Ospino, J; Carot, J

2015-01-01T23:59:59.000Z

410

Magneto-hydrodynamics simulation study of deflagration mode in co-axial plasma accelerators  

SciTech Connect (OSTI)

Experimental studies by Poehlmann et al. [Phys. Plasmas 17(12), 123508 (2010)] on a coaxial electrode magnetohydrodynamic (MHD) plasma accelerator have revealed two modes of operation. A deflagration or stationary mode is observed for lower power settings, while higher input power leads to a detonation or snowplow mode. A numerical modeling study of a coaxial plasma accelerator using the non-ideal MHD equations is presented. The effect of plasma conductivity on the axial distribution of radial current is studied and found to agree well with experiments. Lower conductivities lead to the formation of a high current density, stationary region close to the inlet/breech, which is a characteristic of the deflagration mode, while a propagating current sheet like feature is observed at higher conductivities, similar to the detonation mode. Results confirm that plasma resistivity, which determines magnetic field diffusion effects, is fundamentally responsible for the two modes.

Sitaraman, Hariswaran; Raja, Laxminarayan L. [Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, Texas 78712 (United States)] [Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin, Austin, Texas 78712 (United States)

2014-01-15T23:59:59.000Z

411

Axial force imparted by a current-free magnetically expanding plasma  

SciTech Connect (OSTI)

The axial force imparted from a magnetically expanding, current-free, radiofrequency plasma is directly measured. For an argon gas flow rate of 25 sccm and an effective rf input power of {approx}800W, a maximum force of {approx}6mN is obtained; {approx}3mN of which is transmitted via the expanding magnetic field. The measured forces are reasonably compared with a simple fluid model associated with the measured electron pressure. The model suggests that the total force is the sum of an electron pressure inside the source and a Lorentz force due to the electron diamagnetic drift current and the applied radial magnetic field. It is shown that the Lorentz force is greatest near the magnetic nozzle surface where the radial pressure gradient is largest.

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

2012-08-15T23:59:59.000Z

412

A magnetic liquid deformable mirror for high stroke and low order axially symmetrical aberrations  

E-Print Network [OSTI]

We present a new class of magnetically shaped deformable liquid mirrors made of a magnetic liquid (ferrofluid). Deformable liquid mirrors offer advantages with respect to deformable solid mirrors: large deformations, low costs and the possibility of very large mirrors with added aberration control. They have some disadvantages (e.g. slower response time). We made and tested a deformable mirror, producing axially symmetrical wavefront aberrations by applying electric currents to 5 concentric coils made of copper wire wound on aluminum cylinders. Each of these coils generates a magnetic field which combines to deform the surface of a ferrofluid to the desired shape. We have carried out laboratory tests on a 5 cm diameter prototype mirror and demonstrated defocus as well as Seidel and Zernike spherical aberrations having amplitudes up to 20 microns, which was the limiting measurable amplitude of our equipment

Brousseau, D; Parent, J; Ruel, H J; Borra, Ermanno F.; Brousseau, Denis; Parent, Jocelyn; Ruel, Hubert-Jean

2006-01-01T23:59:59.000Z

413

A magnetic liquid deformable mirror for high stroke and low order axially symmetrical aberrations  

E-Print Network [OSTI]

We present a new class of magnetically shaped deformable liquid mirrors made of a magnetic liquid (ferrofluid). Deformable liquid mirrors offer advantages with respect to deformable solid mirrors: large deformations, low costs and the possibility of very large mirrors with added aberration control. They have some disadvantages (e.g. slower response time). We made and tested a deformable mirror, producing axially symmetrical wavefront aberrations by applying electric currents to 5 concentric coils made of copper wire wound on aluminum cylinders. Each of these coils generates a magnetic field which combines to deform the surface of a ferrofluid to the desired shape. We have carried out laboratory tests on a 5 cm diameter prototype mirror and demonstrated defocus as well as Seidel and Zernike spherical aberrations having amplitudes up to 20 microns, which was the limiting measurable amplitude of our equipment

Denis Brousseau; Ermanno F. Borra; Hubert-Jean Ruel; Jocelyn Parent

2006-11-15T23:59:59.000Z

414

LIFE Chamber Chemical Equilibrium Simulations with Additive Hydrogen, Oxygen, and Nitrogen  

SciTech Connect (OSTI)

In order to enable continuous operation of a Laser Inertial confinement Fusion Energy (LIFE) engine, the material (fill-gas and debris) in the fusion chamber must be carefully managed. The chamber chemical equilibrium compositions for post-shot mixtures are evaluated to determine what compounds will be formed at temperatures 300-5000K. It is desired to know if carbon and or lead will deposit on the walls of the chamber, and if so: at what temperature, and what elements can be added to prevent this from happening. The simulation was conducted using the chemical equilibrium solver Cantera with a Matlab front-end. Solutions were obtained by running equilibrations at constant temperature and constant specific volume over the specified range of temperatures. It was found that if nothing is done, carbon will deposit on the walls once it cools to below 2138K, and lead below 838K. Three solutions to capture the carbon were found: adding pure oxygen, hydrogen/nitrogen combo, and adding pure nitrogen. The best of these was the addition of oxygen which would readily form CO at around 4000K. To determine the temperature at which carbon would deposit on the walls, temperature solutions to evaporation rate equations needed to be found. To determine how much carbon or any species was in the chamber at a given time, chamber flushing equations needed to be developed. Major concerns are deposition of carbon and/or oxygen on the tungsten walls forming tungsten oxides or tungsten carbide which could cause embrittlement and cause failure of the first wall. Further research is needed.

DeMuth, J A; Simon, A J

2009-09-03T23:59:59.000Z

415

Current scaling of axially radiated power in dynamic hohlraums and dynamic hohlraum load design for ZR.  

SciTech Connect (OSTI)

We present designs for dynamic hohlraum z-pinch loads on the 28 MA, 140 ns driver ZR. The scaling of axially radiated power with current in dynamic hohlraums is reviewed. With adequate stability on ZR this scaling indicates that 30 TW of axially radiated power should be possible. The performance of the dynamic hohlraum load on the 20 MA, 100 ns driver Z is extensively reviewed. The baseline z-pinch load on Z is a nested tungsten wire array imploding onto on-axis foam. Data from a variety of x-ray diagnostics fielded on Z are presented. These diagnostics include x-ray diodes, bolometers, fast x-ray imaging cameras, and crystal spectrometers. Analysis of these data indicates that the peak dynamic radiation temperature on Z is between 250 and 300 eV from a diameter less than 1 mm. Radiation from the dynamic hohlraum itself or from a radiatively driven pellet within the dynamic hohlraum has been used to probe a variety of matter associated with the dynamic hohlraum: the tungsten z-pinch itself, tungsten sliding across the end-on apertures, a titanium foil over the end aperture, and a silicon aerogel end cap. Data showing the existence of asymmetry in radiation emanating from the two ends of the dynamic hohlraum is presented, along with data showing load configurations that mitigate this asymmetry. 1D simulations of the dynamic hohlraum implosion are presented and compared to experimental data. The simulations provide insight into the dynamic hohlraum behavior but are not necessarily a reliable design tool because of the inherently 3D behavior of the imploding nested tungsten wire arrays.

Mock, Raymond Cecil; Nash, Thomas J.; Sanford, Thomas W. L.

2007-03-01T23:59:59.000Z

416

Isospin-invariant Skyrme energy-density-functional approach with axial symmetry  

E-Print Network [OSTI]

We develop the isospin-invariant Skyrme-EDF method by considering local densities in all possible isospin channels and proton-neutron (p-n) mixing terms as mandated by the isospin symmetry. The EDF employed has the most general form that depends quadratically on the isoscalar and isovector densities. We test and benchmark the resulting p-n EDF approach, and study the general properties of the new scheme by means of the cranking in the isospin space. We extend the existing axial DFT solver HFBTHO to the case of isospin-invariant EDF approach with all possible p-n mixing terms. Explicit expressions have been derived for all the densities and potentials that appear in the isospin representation. In practical tests, we consider the Skyrme EDF SkM* and, as a first application, concentrate on Hartree-Fock aspects of the problem, i.e., pairing has been disregarded. Calculations have been performed for the (A=78, T~11), (A=40, T~8), and (A=48, T~4) isobaric analog chains. Isospin structure of self-consistent p-n mixed solutions has been investigated with and without the Coulomb interaction, which is the sole source of isospin symmetry breaking in our approach. The extended axial HFBTHO solver has been benchmarked against the symmetry-unrestricted HFODD code for deformed and spherical states. We developed and tested a general isospin-invariant Skyrme-EDF framework. The new approach permits spin-isospin densities that may give rise to, hitherto, unexplored modes in the excitation spectrum. The new formalism has been tested in the Hartree-Fock limit. A systematic comparison between HFODD and HFBTHO results show a maximum deviation of about 10 keV on the total binding energy for deformed nuclei when the Coulomb term is included. Without this term, the results of both solvers agree down to a ~10 eV level.

J. A. Sheikh; N. Hinohara; J. Dobaczewski; T. Nakatsukasa; W. Nazarewicz; K. Sato

2014-05-20T23:59:59.000Z

417

Cyclic powder formation during pulsed injection of hexamethyldisiloxane in an axially asymmetric radiofrequency argon discharge  

SciTech Connect (OSTI)

A new approach of periodic production of dusty plasma consisting of pulsed injection of hexamethyldisiloxane (HMDSO) in argon axially asymmetric radiofrequency (RF) discharge was investigated in this work. The range of plasma operating conditions in which this dusty plasma can exist was closely examined. The obtained results clearly show that a net periodicity in the formation/disappearance of dust particles in the plasma can be maintained on a very large scale of discharge duration. The significance of discharge axial asymmetry to the dust particles behaviour in the plasma is revealed by the development of an asymmetric in shape void shifted towards the powered RF electrode. The key role of the reactive gas and its pulsed injection on each stage of the oscillating process of formation/disappearance of dust particles is disclosed by optical and electrical measurements. It is shown that the period of dusty plasma formation/disappearance is inversely related to the HMDSO injection time. Moreover, the impact of time injection over short period (5 s) is examined. It indicates the conflicting role played by the HMDSO on the reduction of dusty plasma during the reactive gas injection and the reappearance of particles in the plasma during the time off. The electronegative behavior of the plasma in the presence of negatively charged particles seems to explain the energetic modifications in the discharge. A frequency analysis of the floating potential reveals all these cyclic processes. Particularly, in the 10-200 Hz frequency range, the presence and the evolution of dust particles in the plasma over one generation can be observed.

Despax, B.; Makasheva, K. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse 09 (France); CNRS, LAPLACE, F-31062 Toulouse cedex 09 (France); Caquineau, H. [Universite de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d'Energie), 118 route de Narbonne, F-31062 Toulouse 09 (France)

2012-11-01T23:59:59.000Z

418

Probabilistic Analysis of a Monod-type equation by use of a single chamber Microbial Fuel Cell  

E-Print Network [OSTI]

Probabilistic Analysis of a Monod-type equation by use of a single chamber Microbial Fuel Cell Eric for our society. Microbial fuel cells (MFCs) represent a new form of renewable energy by converting of a single chamber Microbial Fuel Cell affect the power density produced in the Microbial Fuel Cell

419

Anode-supported thin-film fuel cells operated in a single chamber configuration 2T-I-12  

E-Print Network [OSTI]

on the anode, producing a complex response in fuel cell power output. Under optimized gas compositions and flowAnode-supported thin-film fuel cells operated in a single chamber configuration 2T-I-12 Zongping of anode-supported, thin-film, single chamber fuel cells (SCFCs) have been investigated. Cells, in which Ni

Haile, Sossina M.

420

Monte Carlo calculations for reference dosimetry of electron beams with the PTW Roos and NE2571 ion chambers  

SciTech Connect (OSTI)

Purpose: To investigate recommendations for reference dosimetry of electron beams and gradient effects for the NE2571 chamber and to provide beam quality conversion factors using Monte Carlo simulations of the PTW Roos and NE2571 ion chambers. Methods: The EGSnrc code system is used to calculate the absorbed dose-to-water and the dose to the gas in fully modeled ion chambers as a function of depth in water. Electron beams are modeled using realistic accelerator simulations as well as beams modeled as collimated point sources from realistic electron beam spectra or monoenergetic electrons. Beam quality conversion factors are calculated with ratios of the doses to water and to the air in the ion chamber in electron beams and a cobalt-60 reference field. The overall ion chamber correction factor is studied using calculations of water-to-air stopping power ratios. Results: The use of an effective point of measurement shift of 1.55 mm from the front face of the PTW Roos chamber, which places the point of measurement inside the chamber cavity, minimizes the difference betweenR{sub 50}, the beam quality specifier, calculated from chamber simulations compared to that obtained using depth-dose calculations in water. A similar shift minimizes the variation of the overall ion chamber correction factor with depth to the practical range and reduces the root-mean-square deviation of a fit to calculated beam quality conversion factors at the reference depth as a function of R{sub 50}. Similarly, an upstream shift of 0.34 r{sub cav} allows a more accurate determination of R{sub 50} from NE2571 chamber calculations and reduces the variation of the overall ion chamber correction factor with depth. The determination of the gradient correction using a shift of 0.22 r{sub cav} optimizes the root-mean-square deviation of a fit to calculated beam quality conversion factors if all beams investigated are considered. However, if only clinical beams are considered, a good fit to results for beam quality conversion factors is obtained without explicitly correcting for gradient effects. The inadequacy of R{sub 50} to uniquely specify beam quality for the accurate selection of k{sub Q} factors is discussed. Systematic uncertainties in beam quality conversion factors are analyzed for the NE2571 chamber and amount to between 0.4% and 1.2% depending on assumptions used. Conclusions: The calculated beam quality conversion factors for the PTW Roos chamber obtained here are in good agreement with literature data. These results characterize the use of an NE2571 ion chamber for reference dosimetry of electron beams even in low-energy beams.

Muir, B. R., E-mail: bmuir@physics.carleton.ca; Rogers, D. W. O., E-mail: drogers@physics.carleton.ca [Physics Department, Carleton Laboratory for Radiotherapy Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)] [Physics Department, Carleton Laboratory for Radiotherapy Physics, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6 (Canada)

2013-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Path-integral solution for a two-dimensional model with axial-vector-current--pseudoscalar derivative interaction  

SciTech Connect (OSTI)

We study a two-dimensional quantum field model with axial-vector-current--pseudoscalar derivative interaction using path-integral methods. We construct an effective Lagrangian by performing a chiral change in the fermionic variables leading to an exact solution of the model.

Botelho, L.C.L.

1985-03-15T23:59:59.000Z

422

Single-scattering properties of tri-axial ellipsoidal mineral dust aerosols: A database for application to radiative transfer calculations  

E-Print Network [OSTI]

Single-scattering properties of tri-axial ellipsoidal mineral dust aerosols: A database Applications and Research, Camp Spring, MD 20746, USA a r t i c l e i n f o Article history: Received 14 Optical properties Database a b s t r a c t This paper presents a user-friendly database software package

Liou, K. N.

423

The effect of axial strain cycling on the critical current density and n-value of ITER niobium-tin  

E-Print Network [OSTI]

The effect of axial strain cycling on the critical current density and n-value of ITER niobium-tin niobium-tin VAC and EM-LMI strands and the detailed characterisation of the EM-LMI-TFMC strand at -0 current density and n-value of two ITER candidate niobium-tin strands (EM- LMI and VAC). The strands were

Hampshire, Damian

424

Supplemental Material for Severson et al. The axial element protein HTP-3 promotes cohesin loading and meiotic axis  

E-Print Network [OSTI]

Supplemental Material for Severson et al. The axial element protein HTP-3 promotes cohesin loading ......................................................................................... 7 Disrupting REC-8, HTP-3, or HTP-1/2 function reduces the lethality of spo-11(me44) mutants ....................................................................................... 13 The htp-3 deletion allele tm3655 phenocopies htp-3(y428). Supplemental Figure 8

Meyer, Barbara

425

Department of Mechanical and Nuclear Engineering Fall 2011 Torque and Axial Measurement Device for Soil Abrasion Testing  

E-Print Network [OSTI]

PENNSTATE Department of Mechanical and Nuclear Engineering Fall 2011 Torque and Axial Measurement Device for Soil Abrasion Testing Overview The Penn State Department of Energy and Mineral Engineering instrument they are using to develop a soil abrasion index. While our team's initially proposed concept met

Demirel, Melik C.

426

Dissolved inorganic carbon isotopic composition of low-temperature axial and ridge-flank hydrothermal fluids of the Juan de Fuca Ridge  

E-Print Network [OSTI]

carbon isotopic composition of low-temperature axial and ridge-flank hydrothermal fluids of the Juan deDissolved inorganic carbon isotopic composition of low-temperature axial and ridge-flank hydrothermal fluids of the Juan de Fuca Ridge Brett D. Walker a,, Matthew D. McCarthy a , Andrew T. Fisher b

Fisher, Andrew

427

Neutron and gamma detector using an ionization chamber with an integrated body and moderator  

DOE Patents [OSTI]

A detector for detecting neutrons and gamma radiation includes a cathode that defines an interior surface and an interior volume. A conductive neutron-capturing layer is disposed on the interior surface of the cathode and a plastic housing surrounds the cathode. A plastic lid is attached to the housing and encloses the interior volume of the cathode forming an ionization chamber, into the center of which an anode extends from the plastic lid. A working gas is disposed within the ionization chamber and a high biasing voltage is connected to the cathode. Processing electronics are coupled to the anode and process current pulses which are converted into Gaussian pulses, which are either counted as neutrons or integrated as gammas, in response to whether pulse amplitude crosses a neutron threshold. The detector according to the invention may be readily fabricated into single or multilayer detector arrays.

Ianakiev, Kiril D.; Swinhoe, Martyn T.; Lestone, John Paul

2006-07-18T23:59:59.000Z

428

Acoustic studies for alpha background rejection in dark matter bubble chamber detectors  

SciTech Connect (OSTI)

COUPP (Chicagoland Observatory for Underground Particle Physics) is an experiment with bubble chambers able to detect dark matter directly either with Spin-Dependent or with Spin-Independent interactions. The target material is a superheated liquid (usually CF3I) that can be bubble nucleated due to nuclear recoils produced by elastic collisions of dark matter particles. The bubble growth inside the chamber is accompanied with an acoustic signature. The acoustic technique has been successfully used to have a good alpha discrimination (about 99%). In this paper, we present different studies and results related with the characterization of the acoustic properties of the detector and the different phenomena involved in the acoustic measurements of the bubble growth, such as sound generation, sound transmission and optimization of piezoelectric transducers.

Bou-Cabo, M.; Felis, I.; Ardid, M.; Collaboration: COUPP Collaboration

2013-08-08T23:59:59.000Z

429

MIMAC: MIcro-tpc MAtrix of Chambers for dark matter directional detection  

E-Print Network [OSTI]

Directional detection of non-baryonic Dark Matter is a promising search strategy for discriminating WIMP events from neutrons, the ultimate background for dark matter direct detection. This strategy requires both a precise measurement of the energy down to a few keV and 3D reconstruction of tracks down to a few mm. The MIMAC (MIcro-tpc MAtrix of Chambers) collaboration has developed in the last years an original prototype detector based on the direct coupling of large pixelized micromegas with a special developed fast self-triggered electronics showing the feasibility of a new generation of directional detectors. The first bi-chamber prototype has been installed at Modane, underground laboratory in June 2012. The first undergournd background events, the gain stability and calibration are shown. The first spectrum of nuclear recoils showing 3D tracks coming from the radon progeny is presented.

Santos, D; Bouly, J L; Bourrion, O; Fourel, Ch; Guillaudin, O; Lamblin, J; Mayet, F; Muraz, J F; Richer, J P; Riffard, Q; Lebreton, L; Maire, D; Busto, J; Brunner, J; Fouchez, D

2013-01-01T23:59:59.000Z

430

Addendum to the Technical Design Report for the Upgrade of the ALICE Time Projection Chamber  

E-Print Network [OSTI]

This is the addendum to the TDR of the upgrade of the ALICE Time Projection Chamber (CERN-LHCC-2013-020 ; ALICE-TDR-016). The key objective of the upgrade is the replacement of the present MWPC-based readout chambers by detectors that allow continuous operation without active ion gating. In the TDR, we propose a solution that employs stacks of four Gas Electron Multipliers (GEMs) and demonstrate that it fulfills the design specifications, in particular in terms of intrinsic position resolution, energy resolution, and ion backflow. In this document we demonstrate with additional results from both detector R&D and simulations that the technological solution chosen in the TDR has sufficient safety margin for a successful campaign with the upgraded detector in RUN 3 and beyond.

The ALICE Collaboration

2015-01-01T23:59:59.000Z

431

IFE Final Optics and Chamber Dynamics Modeling and Experiments Final Technical Report  

SciTech Connect (OSTI)

Our OFES-sponsored research on IFE technology originally focused on studies of grazing-incidence metal mirrors (GIMM's). After the addition of GIMM research to the High Average Power Laser (HAPL) program, our OFES-sponsored research evolved to include laser propagation studies, surface material evolution in IFE wetted-wall chambers, and magnetic intervention. In 2003, the OFES IFE Technology program was terminated. We continued to expend resources on a no-cost extension in order to complete student research projects in an orderly way and to help us explore new research directions. Those explorations led to funding in the field of extreme ultraviolet lithography, which shares many issues in common with inertial fusion chambers, and the field of radiative properties of laser-produced plasma.

F. Najmabadi; M. S. Tillack

2006-01-11T23:59:59.000Z

432

Overview of IFE chamber and target technologies R&D in the U.S.  

SciTech Connect (OSTI)

The U.S. Department of Energy, Office of Fusion Energy Science (OFES) formed the Virtual Laboratory for Technology (VLT) to develop the technologies needed to support near term fusion experiments and to provide the basis for future magnetic and inertial fusion energy power plants. The scope of the inertial fusion energy (IFE) element of the VLT includes the fusion chamber, driver/chamber interface, target fabrication and injection, and safety and environmental assessment for IFE. Lawrence Livermore National Laboratory, in conjunction with other laboratories, universities and industry, has written an R&D plan to address the critical issues in these areas over the next 5 years in a coordinated manner. This paper provides an overview of the US. research activities addressing these critical issues.

Meier, W R; Abdou, M A; Kulcinski, G L; Moir, R W; Nobile, A; Peterson, P F; Petti, D A; Schultz, K R; Tillack, M S; Yoda, M

2000-09-22T23:59:59.000Z

433

Target Chamber  

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

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security AdministrationcontrollerNanocrystallineForeign ObjectOUR8, 2013 FINAL MEETING

434

Efficiency determination of resistive plate chambers for fast quasi-monoenergetic neutrons  

E-Print Network [OSTI]

Composite detectors made of stainless steel converters and multigap resistive plate chambers have been irradiated with quasi-monoenergetic neutrons with a peak energy of 175MeV. The neutron detection efficiency has been determined using two different methods. The data are in agreement with the output of Monte Carlo simulations. The simulations are then extended to study the response of a hypothetical array made of these detectors to energetic neutrons from a radioactive ion beam experiment.

M. Röder; Z. Elekes; T. Aumann; D. Bemmerer; K. Boretzky; C. Caesar; T. E. Cowan; J. Hehner; M. Heil; M. Kempe; V. Maroussov; O. Nusair; A. V. Prokofiev; R. Reifarth; M. Sobiella; D. Stach; A. Wagner; D. Yakorev; A. Zilges; K. Zuber

2014-07-10T23:59:59.000Z

435

Apparatus for monitoring tritium in tritium contaminating environments using a modified Kanne chamber  

DOE Patents [OSTI]

A conventional Kanne tritium monitor has been redesigned to reduce its sensitivity to such contaminants as tritiated water vapor and tritiated oil. The high voltage electrode has been replaced by a wire cylinder and the collector electrode has been reduced in diameter. The area sensitive to contamination has thereby been reduced by about a factor of forty while the overall apparatus sensitivity and operation has not been affected. The design allows for in situ decontamination of the chambers, if necessary.

Anderson, David F. (Los Alamos, NM)

1984-01-01T23:59:59.000Z

436

Apparatus for monitoring tritium in tritium-contaminating environments using a modified Kanne chamber  

DOE Patents [OSTI]

A conventional Kanne tritium monitor has been redesigned to reduce its sensitivity to such contaminants as tritiated water vapor and tritiated oil. The high voltage electrode has been replaced by a wire cylinder and the collector electrode has been reduced in diameter. The area sensitive to contamination has thereby been reduced by about a factor of forty while the overall apparatus sensitivity and operation has not been affected. The design allows for in situ decontamination of the chambers, if necessary.

Anderson, D.F.

1981-01-27T23:59:59.000Z

437

A Multiwire Proportional Chamber for Precision Studies of Neutron Beta Decay Angular Correlations  

E-Print Network [OSTI]

A new multiwire proportional chamber (MWPC) was designed and constructed for precision studies of neutron beta decay angular correlations. Its design has several novel features, including the use of low pressure neopentane as the MWPC gas and an entrance window made of thin Mylar sheet reinforced with Kevlar fibers. In the initial off-line performance tests, the gas gain of neopentane and the position resolution were studied.

Ito, T M; Filippone, B W; Martin, J W; Plaster, B; Rybka, G; Yuan, J; 10.1016/j.nima.2006.11.026

2008-01-01T23:59:59.000Z

438

A Multiwire Proportional Chamber for Precision Studies of Neutron Beta Decay Angular Correlations  

E-Print Network [OSTI]

A new multiwire proportional chamber (MWPC) was designed and constructed for precision studies of neutron beta decay angular correlations. Its design has several novel features, including the use of low pressure neopentane as the MWPC gas and an entrance window made of thin Mylar sheet reinforced with Kevlar fibers. In the initial off-line performance tests, the gas gain of neopentane and the position resolution were studied.

T. M. Ito; R. Carr; B. W. Filippone; J. W. Martin; B. Plaster; G. Rybka; J. Yuan

2007-02-10T23:59:59.000Z

439

Microwave remote plasma enhanced-atomic layer deposition system with multicusp confinement chamber  

SciTech Connect (OSTI)

A microwave remote Plasma Enhanced-Atomic Layer Deposition system with multicusp confinement chamber is established at the Plasma and Beam Physics research facilities, Chiang Mai, Thailand. The system produces highly-reactive plasma species in order to enhance the deposition process of thin films. The addition of the multicusp magnetic fields further improves the plasma density and uniformity in the reaction chamber. Thus, the system is more favorable to temperature-sensitive substrates when heating becomes unwanted. Furthermore, the remote-plasma feature, which is generated via microwave power source, offers tunability of the plasma properties separately from the process. As a result, the system provides high flexibility in choice of materials and design experiments, particularly for low-temperature applications. Performance evaluations of the system were carried on coating experiments of Al{sub 2}O{sub 3} layers onto a silicon wafer. The plasma characteristics in the chamber will be described. The resulted Al{sub 2}O{sub 3} films—analyzed by Rutherford Backscattering Spectrometry in channeling mode and by X-ray Photoelectron Spectroscopy techniques—will be discussed.

Dechana, A. [Program of Physics and General Science, Faculty of Science and Technology, Songkhla Rajabhat University, Songkhla 90000 (Thailand); Thamboon, P. [Science and Technology Research Institute, Chiang Mai University, Chiang Mai 50200 (Thailand); Boonyawan, D., E-mail: dheerawan.b@cmu.ac.th [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand)

2014-10-15T23:59:59.000Z

440

Interpretation of Secondary Organic Aerosol Formation from Diesel Exhaust Photooxidation in an Environmental Chamber  

SciTech Connect (OSTI)

Secondary organic aerosol (SOA) formation from diesel exhaust in a smog chamber was investigated. Particle volume measurement based on mobility diameter is shown to underestimate SOA formation from diesel exhaust due to the external void space of agglomerate particles, in which case mass-based measurement technique is necessary. Rapid determination of particle effective density as a function of particle mass was performed by an Aerosol Particle Mass analyzer – Scanning Mobility Particle Sizer (APM-SMPS) to obtain particle mass concentration and fractal dimension. Continuous aging of aerosol was observed in terms of atomic ratio (O/C), from 0.05 to 0.25 in 12 hours, underscoring the importance of multi-generational oxidation of low-volatile organic vapors emitted from diesel engine as the significant source of oxygenated SOA. Experimental conditions possibly have strong impacts on physical evolution of diesel particulates in a smog chamber. Higher particle effective densities were observed when raw exhaust was injected into a full bag as opposed to filling a bag with diluted exhaust using an ejector diluter. When longer transfer line was used for injecting diesel exhaust into the smog chamber, rapid particle coagulation was observed, leading to increasing particle volume concentration in dark while its mass concentration is decreasing.

Nakao, Shunsuke; Shrivastava, ManishKumar B.; Nguyen, Anh; Jung, Hee-Jung; Cocker, David R.

2011-04-14T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Comparative study of ionization chamber detectors vis-a-vis a CCD detector for dispersive XAS measurement in transmission geometry  

SciTech Connect (OSTI)

We have designed and fabricated parallel plate ionization chamber detectors and voltage vs. current characteristics (V-I curve) of the detectors were recorded with synchrotron radiation to qualify for use in X-ray Absorption Spectroscopy (XAS) measurements. After qualifying the ionization chambers, the detectors were used in the dispersive EXAFS beamline (BL-08) at INDUS-2 SRS in Turbo-XAS geometry. Using the same setup and under the same setting, XAS spectra were also recorded with a CCD detector and the observation on relative performance of the ionization chamber vis-a-vis the CCD detector is presented in this paper.

Poswal, A. K.; Agrawal, A.; Bhattachryya, D.; Jha, S. N.; Sahoo, N. K. [Applied Spectroscopy Division, Bhabha Atomic Research Centre, Mumbai -400 085 (India)

2013-02-05T23:59:59.000Z

442

Algebraic stress model for axial flow in a bare rod-bundle  

SciTech Connect (OSTI)

The problem of predicting transport properties for momentum and heat across the boundaries of interconnected channels has been the subject of many investigations. In the particular case of axial flow through rod-bundles, transport coefficients for channel faces aligned with rod centers are known to be considerably higher than those calculated by simple isotropic theories. And yet, it was been found that secondary flows play only a minor role in this overall transport, being turbulence highly enhanced across that hypothetical surface. In order to numerically predict the correct amount of the quantity being transported, the approach taken by many investigators was then to artificially increase the diffusion coefficient obtained via a simple isopropic theory (usually the standard k-epsilon model) and numerically match the correct experimentally observed mixing rates. The present paper reports an attempt to describe the turbulent stresses by means of an Algebraic Stress Model for turbulence. Relative turbulent kinetic energy distribution in all three directions are presented and compared with experiments in a square lattice. The strong directional dependence of transport terms are then obtained via a model for the Reynolds stresses. The results identify a need for a better representation of the mean-flow field part of the pressure-strain correlation term.

de Lemos, M.J.S.

1987-01-01T23:59:59.000Z

443

Axisymmetry vs. nonaxisymmetry of hydromagnetic Taylor-Couette flows with axial electric currents  

E-Print Network [OSTI]

The stability of a Taylor-Couette flow with resting outer cylinder under the influence of a homogeneous axial electric current is investigated. In the linear theory the critical Reynolds number for axisymmetric perturbations Re=68 is not influenced by the current-induced magnetic field but all the axisymmetric magnetic perturbations decay. The nonaxisymmetric perturbations with |m|=1 are excited even without rotation for large enough Hartmann numbers ('Tayler Instability') but the growth rate increases with Reynolds number. In the nonlinear regime shear energy is pumped into the neighboring modes m=0 and |m|=2. The ratio q of the energy of the magnetic |m|=1 modes and the toroidal background field is very small for the pure (non-rotating) Tayler instability and grows strongly if differential rotation is present. For super-Alfv\\'enic rotation the energy in the |m|=1 modes of flow and field are in equipartition, with about 1% of the centrifugal energy of the inner cylinder. If the electric current is strong eno...

Gellert, M; Rüdiger, G

2013-01-01T23:59:59.000Z

444

Growth and electrical rectification in axial in-situ doped p-n junction germanium nanowires  

SciTech Connect (OSTI)

In this work, we demonstrate the vapor-liquid-solid (VLS) growth and electrical properties of axial in-situ doped p-n junction Ge nanowires (NWs). In-situ doping of the NWs was accomplished by introducing dopant gases (diborane and phosphine) together with GeH{sub 4} in the growth process. By changing dopant sources during growth, a p-n junction can be realized along the axis of the NWs. Metal contacts to the wires were defined using e-beam lithography patterning, followed by 100 nm Ni sputter deposition and lift-off. Four-point measurements of the fabricated devices at room temperature and at 77 K clearly show rectification with on/off current ratio up to two orders of magnitude when the bias is applied across the p-n junction. The ideality factor of the junction current points to a significant generation-recombination contribution. The Ohmic characteristics in the p and n regions outside the junction make it possible to estimate the doping levels. We also observed backgate control of the NW junction current.

Picraux, Samuel T [Los Alamos National Laboratory; Dayeh, Shadi [Los Alamos National Laboratory; Zaslavsky, Alexander [BROWN U; Le, Son T [BROWN U

2009-01-01T23:59:59.000Z

445

Control rod worth and related nuclear characteristics of an axially heterogeneous liquidmetal fast breeder reactor core  

SciTech Connect (OSTI)

An axially heterogeneous core (AHC) concept is applied to a 1000-MW(electric)-class tank-type liquidmetal fast breeder reactor (LMFBR). This AHC is characterized by a disk-shaped internal blanket with a radial thickness adjustment at the core midplane. The nuclear characteristics connected with control rod worth of the AHC are analyzed and compared with those of a homogeneous core (HOC) of the same power rating. The neutronics analysis shows that the reactivity insertion due to the vertical displacement of control rods relative to the core, which is an important safety characteristic of a tank-type LMFBR core, is significantly decreased in the AHC because of the reduced control worth requirement and smaller peakto-average differential worth in the primary control system. This allows the AHC to have a vertical displacement 50% greater than that of the HOC and may offer less rigid design conditions for roof slab stiffness and core support systems in a tank-type LMFBR. A reduction in the number of primary control rods is also possible because of a smaller control worth requirement and a better power peaking factor. The work was sponsored by a federation of Japanese electric power companies and performed under the guidance of the fast breeder reactor project office.

Kawashima, K.; Inayaki, T.; Inoue, K.; Kaneto, K.

1985-08-01T23:59:59.000Z

446

Multi-stage axial-flux PM machine for wheel direct drive  

SciTech Connect (OSTI)

The design of direct-driven wheel motors must comply with diameter restriction due to housing the motor in a wheel rim and allow the achievement of very high torque density and overload capability. Slotless axial-flux permanent magnet machines (AFPMs) prove to be one best candidate for application in electric vehicles as direct-drive wheel motors, as in comparison with conventional machines they allow designs with higher compactness, lightness and efficiency. The paper presents a newly-conceived AFPM which has multi-stage structure and water-cooled ironless stator. In the proposed new topology of the machine the space formerly occupied by the toroidal core becomes a water duct, which removes heat directly from the interior surface of the stator winding. The high efficiency of the machine cooling arrangement allows long-term 100% overload operation and great reduction of the machine weight. The multistage structure of the machine is suited to overcome the restriction on the machine diameter and meet the torque required at the wheel shaft. The paper gives guidelines for the design of a multi-stage AFPM with water-cooled ironless stator, and describes characteristics of a two-stage prototype machine rated 220 Nm, 1,100 rpm.

Caricchi, F.; Crescimbini, F.; Mezzetti, F.; Santini, E. [Univ. of Rome La Sapienza (Italy). Dept. of Electrical Engineering

1995-12-31T23:59:59.000Z

447

Design of a high power density, permanent magnet, axial gap dc motor  

SciTech Connect (OSTI)

In the design of drive motors for undersea vehicles, the premium placed on noise suppression suggests the use of a brush-commutated dc motor. The additional constraints of weight and volume, as well as unusual configuration, presents the axial air-gap configuration, with a permanent magnet field, as a viable candidate. In such a configuration the design of the brushes and commutator and the resulting structure becomes critical. The report describes a novel solution to this problem. The basic motor consists of two discs containing permanent magnets on either side of a magnetic structure containing the copper windings. An advantage of this motor concept is that copper cooling may easily be accomplished through the use of liquid circulating through the stator windings. The role of field and armature in a conventional disc motor configuration are reversed. The two discs containing the permanent magnets are rotating. The brushes are on the discs. The magnetic structure with the coils is stationary. The commutator bars are imbedded in the stationary member. Input power is supplied to the brushes through a brush-and-slip ring assembly. An electromagnetic design analysis for a 92 ft-lb, 700 rpm motor was performed. A finite element analysis has been conducted and the results show that magnetic saturation is not a limiting factor in this design. The motor torque is achievable within weight and volume constraints. 9 figs., 1 tab.

Hawsey, R.A.; Daniel, D.S.; Thomas, R.J. (Oak Ridge National Lab., TN (USA)); Bailey, J.M. (Tennessee Univ., Knoxville, TN (USA))

1990-01-01T23:59:59.000Z

448

Axial gap permanent-magnet machine with reluctance poles and PM element covers  

SciTech Connect (OSTI)

An electric machine (10) has a disk-shaped rotor (24) disposed in an operating space between two opposing stator assemblies (11, 12) to provide two axial air gaps (15, 16). The rotor (24) has a hub (28) and an outer ring (26) of non-magnetic material and is further provided with a plurality of permanent magnetic elements (25) for coupling flux that is induced by the magnetic field of the stator assemblies (11, 12). The permanent magnetic elements (25) are spaced apart and reluctance poles (27) are positioned in spaces between the magnetic elements (25) to couple additional flux induced by the magnetic field of the stator assemblies (11, 12). Various constructions and shapes (40-45) for the PM magnetic elements (25) are disclosed, and including PM covers (60) of ferromagnetic material for enhancing q-axis flux in the air gaps (15, 16) and for reducing harmonics where toothed stators are used. Methods of providing increased torque using the the various rotor constructions are also disclosed.

Hsu, John S [Oak Ridge, TN; McKeever, John W [Oak Ridge, TN

2009-04-07T23:59:59.000Z

449

The twofold emergence of the $a_1$ axial vector meson in high energy hadronic production  

E-Print Network [OSTI]

The high statistics COMPASS results on diffractive dissociation $\\pi N \\rightarrow \\pi \\pi \\pi N$ suggest that the isospin $I=1$ spin-parity $J^{PC}= 1^{++}$ $a_1(1260)$ resonance could be split into two states: $a_1(1260)$ decaying into an S-wave $\\rho\\pi$ system, and $a_1^\\prime(1420)$ decaying into a P-wave $f_0(980)\\pi$ system. We analyse the reaction by incorporating our previous treatment of resonant re-scattering corrections in the Drell-Deck forward production process. Our results show that the COMPASS results are fully consistent with the existence of a single axial-vector $a_1$ resonance. The characteristic structure of the production process, which differs in the two orbital angular momentum states, plays a crucial role in this determination. Provided the theoretical analysis of the reaction is done in a consistent manner, this single resonance produces two peaks at different locations in the two channels, with a rapid increase of the phase difference between their amplitudes arising mainly from th...

Basdevant, Jean-Louis

2015-01-01T23:59:59.000Z

450

Dependence with air density of the response of the PTW SourceCheck ionization chamber for low energy brachytherapy sources  

SciTech Connect (OSTI)

Purpose: Air-communicating well ionization chambers are commonly used to assess air kerma strength of sources used in brachytherapy. The signal produced is supposed to be proportional to the air density within the chamber and, therefore, a density-independent air kerma strength is obtained when the measurement is corrected to standard atmospheric conditions using the usual temperature and pressure correction factor. Nevertheless, when assessing low energy sources, the ionization chambers may not fulfill that condition and a residual density dependence still remains after correction. In this work, the authors examined the behavior of the PTW 34051 SourceCheck ionization chamber when measuring the air kerma strength of {sup 125}I seeds.Methods: Four different SourceCheck chambers were analyzed. With each one of them, two series of measurements of the air kerma strength for {sup 125}I selectSeed{sup TM} brachytherapy sources were performed inside a pressure chamber and varying the pressure in a range from 747 to 1040 hPa (560 to 780 mm Hg). The temperature and relative humidity were kept basically constant. An analogous experiment was performed by taking measurements at different altitudes above sea level.Results: Contrary to other well-known ionization chambers, like the HDR1000 PLUS, in which the temperature-pressure correction factor overcorrects the measurements, in the SourceCheck ionization chamber they are undercorrected. At a typical atmospheric situation of 933 hPa (700 mm Hg) and 20 °C, this undercorrection turns out to be 1.5%. Corrected measurements show a residual linear dependence on the density and, as a consequence, an additional density dependent correction must be applied. The slope of this residual linear density dependence is different for each SourceCheck chamber investigated. The results obtained by taking measurements at different altitudes are compatible with those obtained with the pressure chamber.Conclusions: Variations of the altitude and changes in the weather conditions may produce significant density corrections, and that effect should be taken into account. This effect is chamber-dependent, indicating that a specific calibration is necessary for each particular chamber. To our knowledge, this correction has not been considered so far for SourceCheck ionization chambers, but its magnitude cannot be neglected in clinical practice. The atmospheric pressure and temperature at which the chamber was calibrated need to be taken into account, and they should be reported in the calibration certificate. In addition, each institution should analyze the particular response of its SourceCheck ionization chamber and compute the adequate correction factors. In the absence of a suitable pressure chamber, a possibility for this assessment is to take measurements at different altitudes, spanning a wide enough air density range.

Tornero-López, Ana M.; Guirado, Damián; Ruiz-Arrebola, Samuel [Servicio de Radiofísica y Protección Radiológica, Hospital Universitario San Cecilio, E-18012 Granada (Spain)] [Servicio de Radiofísica y Protección Radiológica, Hospital Universitario San Cecilio, E-18012 Granada (Spain); Perez-Calatayud, Jose [Servicio de Radioterapia, Unidad de Radiofísica, Hospital Universitario y Politécnico La Fe, E-46026 Valencia (Spain)] [Servicio de Radioterapia, Unidad de Radiofísica, Hospital Universitario y Politécnico La Fe, E-46026 Valencia (Spain); Simancas, Fernando; Lallena, Antonio M. [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain)] [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain); Gazdic-Santic, Maja [Department of Medical Physics and Radiation Safety, Clinical Centre of Sarajevo University, 71000 Sarajevo (Bosnia and Herzegovina)] [Department of Medical Physics and Radiation Safety, Clinical Centre of Sarajevo University, 71000 Sarajevo (Bosnia and Herzegovina)

2013-12-15T23:59:59.000Z

451

Wide-field functional imaging of blood flow and hemoglobin oxygen saturation in the rodent dorsal window chamber.  

E-Print Network [OSTI]

et al. , editors. Anesthesia and Analgesia in LaboratoryPlace the animal in a gas anesthesia chamber filled with 5%much longer than with gas anesthesia. Conversely, using gas

2011-01-01T23:59:59.000Z

452

Analysis of rabbit intervertebral disc physiology based on water metabolism. II. Changes in normal intervertebral discs under axial vibratory load  

SciTech Connect (OSTI)

Metabolic changes induced by axial vibratory load to the spine were investigated based on water metabolism in normal intervertebral discs of rabbits with or without pentobarbital anesthesia. Tritiated water concentration in the intervertebral discs of unanesthetized rabbits was reduced remarkably by axial vibration for 30 minutes using the vibration machine developed for this study. Repeated vibratory load for 18 and 42 hours duration showed the recovery of /sup 3/H/sub 2/O concentration of the intervertebral disc without anesthesia. Computer simulation suggested a reduction of blood flow surrounding the intervertebral disc following the vibration stress. However, no reduction of the /sup 3/H/sub 2/O concentration in the intervertebral disc was noted under anesthesia. Emotional stress cannot be excluded as a factor in water metabolism in the intervertebral disc.

Hirano, N.; Tsuji, H.; Ohshima, H.; Kitano, S.; Itoh, T.; Sano, A.

1988-11-01T23:59:59.000Z

453

B -> K1 gamma and tests of factorization for two-body non leptonic Bdecays with axial-vector mesons  

E-Print Network [OSTI]

The large branching ratio for B-> K1 gamma recently measured at Belle implies a large B -> K1 transition form factor and large branching ratios for non leptonic B decays involving an axial-vector meson. In this paper we present an analysis of two-body B decays with an axial-vector meson in the final state using naive factorization and the B -> K1 form factors obtained from the measured radiative decays. We find that the predicted B -> J/psi K1 branching ratio is in agreement with experiment. We also suggest that the decay rates of B -> K1 pi, B -> a1 K and B -> b1 K could be used to test the factorization ansatz.

G. Nardulli; T. N. Pham

2005-07-30T23:59:59.000Z

454

Experimental verification of J. S. Alford's mathematical model that predicts Alford's destabilizing force in axial flow machinery  

E-Print Network [OSTI]

compressors and turbines causes unbalanced torque forces which, in turn, can cause severe rotor whirl; a rotordynamic instabzlity. In his 1965 paper, "Protecting Turbomachinery from Self Excited Rotor 'whirl", Alford presented the equations to predict... were prominent during operation of the rotors at high pressures and power levels. Alford presents two mechanisms which can cause severe rotor whirl in axial compressors and turbines. One is due to the circumferential variation of static pressure...

Laudadio, Frank James

1981-01-01T23:59:59.000Z

455

Axial and transverse acoustic radiation forces on a fluid sphere placed arbitrarily in Bessel beam standing wave tweezers  

SciTech Connect (OSTI)

The axial and transverse radiation forces on a fluid sphere placed arbitrarily in the acoustical field of Bessel beams of standing waves are evaluated. The three-dimensional components of the time-averaged force are expressed in terms of the beam-shape coefficients of the incident field and the scattering coefficients of the fluid sphere using a partial-wave expansion (PWE) method. Examples are chosen for which the standing wave field is composed of either a zero-order (non-vortex) Bessel beam, or a first-order Bessel vortex beam. It is shown here, that both transverse and axial forces can push or pull the fluid sphere to an equilibrium position depending on the chosen size parameter ka (where k is the wave-number and a the sphere’s radius). The corresponding results are of particular importance in biophysical applications for the design of lab-on-chip devices operating with Bessel beams standing wave tweezers. Moreover, potential investigations in acoustic levitation and related applications in particle rotation in a vortex beam may benefit from the results of this study. -- Highlights: •The axial and transverse forces on a fluid sphere in acoustical Bessel beams tweezers are evaluated. •The attraction or repulsion to an equilibrium position in the standing wave field is examined. •Potential applications are in particle manipulation using standing waves.

Mitri, F.G., E-mail: mitri@chevron.com

2014-03-15T23:59:59.000Z

456

Experimental Investigation of Axial and Beam-Riding Propulsive Physics with TEA CO{sub 2} laser  

SciTech Connect (OSTI)

A twin Lumonics K922M pulsed TEA CO{sub 2} laser system (pulse duration of approximately 100 ns FWHM spike, with optional 1 {mu}s tail, depending upon laser gas mix) was employed to experimentally measure both axial thrust and beam-riding behavior of Type no. 200 lightcraft engines, using a ballistic pendulum and Angular Impulse Measurement Device (AIMD, respectively. Beam-riding forces and moments were examined along with engine thrust-vectoring behavior, as a function of: a) laser beam lateral offset from the vehicle axis of symmetry; b) laser pulse energy ({approx}12 to 40 joules); c) pulse duration (100 ns, and 1 {mu}s); and d) engine size (97.7 mm to 161.2 mm). Maximum lateral momentum coupling coefficients (C{sub M}) of 75 N-s/MJ were achieved with the K922M laser whereas previous PLVTS laser (420 J, 18 {mu}s duration) results reached only 15 N-s/MJ--an improvement of 5x. Maximum axial C{sub M} performance with the K922M reached 225 N-s/MJ, or about {approx}3x larger than the lateral C{sub M} values. These axial C{sub M} results are sharply higher than the 120 N/MW previously reported for long pulse (e.g., 10-18 {mu}s)CO{sub 2} electric discharge lasers.

Kenoyer, D. A.; Salvador, I.; Myrabo, L. N.; Notaro, S. N.; Bragulla, P. W. [Department of Mechanical, Aeronautical, and Nuclear Engineering, Rensselaer Polytechnic Institute (United States)

2010-10-08T23:59:59.000Z

457

Dynamics of multiple viscoelastic carbon nanotube based nanocomposites with axial magnetic field  

SciTech Connect (OSTI)

Nanocomposites and magnetic field effects on nanostructures have received great attention in recent years. A large amount of research work was focused on developing the proper theoretical framework for describing many physical effects appearing in structures on nanoscale level. Great step in this direction was successful application of nonlocal continuum field theory of Eringen. In the present paper, the free transverse vibration analysis is carried out for the system composed of multiple single walled carbon nanotubes (MSWCNT) embedded in a polymer matrix and under the influence of an axial magnetic field. Equivalent nonlocal model of MSWCNT is adopted as viscoelastically coupled multi-nanobeam system (MNBS) under the influence of longitudinal magnetic field. Governing equations of motion are derived using the Newton second low and nonlocal Rayleigh beam theory, which take into account small-scale effects, the effect of nanobeam angular acceleration, internal damping and Maxwell relation. Explicit expressions for complex natural frequency are derived based on the method of separation of variables and trigonometric method for the “Clamped-Chain” system. In addition, an analytical method is proposed in order to obtain asymptotic damped natural frequency and the critical damping ratio, which are independent of boundary conditions and a number of nanobeams in MNBS. The validity of obtained results is confirmed by comparing the results obtained for complex frequencies via trigonometric method with the results obtained by using numerical methods. The influence of the longitudinal magnetic field on the free vibration response of viscoelastically coupled MNBS is discussed in detail. In addition, numerical results are presented to point out the effects of the nonlocal parameter, internal damping, and parameters of viscoelastic medium on complex natural frequencies of the system. The results demonstrate the efficiency of the suggested methodology to find the closed form solutions for the free vibration response of multiple nanostructure systems under the influence of magnetic field.

Karli?i?, Danilo; Caji?, Milan [Mathematical Institute of the SASA, Kneza Mihaila 36, Belgrade 11001 (Serbia); Murmu, Tony [School of Engineering, University of the West of Scotland, Paisley PA12BE (United Kingdom); Kozi?, Predrag [Faculty of Mechanical Engineering, University of Niš, A. Medvedeva 14, 18000 Niš (Serbia); Adhikari, Sondipon [College of Engineering, Swansea University, Singleton Park, Swansea SA2 8PP (United Kingdom)

2014-06-21T23:59:59.000Z

458

Criticality and axial offset searches based on the integrated neutron balance approach  

SciTech Connect (OSTI)

Criticality and axial offset (AO) searches are key features in the simulation of plant operation procedures. Typically, the dedicated algorithms consist of either a Newton method or a secant method that features the successive computation of difference quotients to be used as derivatives. Within this context, computational robustness and efficiency are of paramount importance. This applies in particular to when the variations imposed during the search are spatially heterogeneous, such as in the case of tuning control rod positions for achieving target AO. In order to optimize this kind of search capability in AREVA NP's reactor code ARTEMIS in accordance with this design principle, a generalized approach has been implemented that harmonizes very well numerically with the overall multi-physics iterative solution process. As embedded in the latter, the new neutronic integral re-balancing approach is defined through periodic whole-core space-energy integrations of the principal terms in the core-integrated process-rate balance terms (i.e. neutron absorption, production and leakage). This procedure yields sequences of single zero-dimensional equations from which the chosen tuning parameters can be solved directly in dependence of the imposed (and systematically fixed) values for the response quantities k{sub eff} and/or AO. The converged result of the iteration sequence of successively obtained search parameter values is final in terms of being fully consistent with the entire set of multi-physics equations while enabling the accurate fulfillment of the target response value. The k etc and AO searches can be pursued simultaneously. Judging from the results of pursued verifications, the neutronic integral re-balancing approach fulfils the above-mentioned expectations convincingly. Specific verification examples are presented, such as the determination of the insertion depth of a critical control bank, a double search on target criticality and target AO by adjusting the boron concentration and the position of a control bank, and a critical power search during reactor cycle stretch out. (authors)

Dall'Osso, A. [AREVA NP Tour AREVA, 92084 Paris La Defense Cedex (France); Van Geemert, R. [AREVA GmbH, Paul Gossenstrasse 100, D-91058 Erlangen (Germany)

2013-07-01T23:59:59.000Z

459

Role of the axial vector a{sub 1}-meson exchange in hypernuclear nonmesonic weak decays  

SciTech Connect (OSTI)

In the meson-theoretical potential model for the study of the nonmesonic decay rates and asymmetries of hypernuclei, for the first time, the axial-vector a{sub 1} meson (J{sup PC}=1{sup ++},m{sub a{sub 1}}=1230 MeV) is introduced. The a{sub 1} meson is the chiral partner of the {rho} meson and has been treated in the meson-pair exchange framework as {rho}{pi}/a{sub 1} and {sigma}{pi}/a{sub 1}. This is analogous to the treatment of {rho} and {sigma} exchange in our model. The a{sub 1}-meson exchange is found to give remarkable modifications of the parity-conserving decay potentials ({sup 1,3}S{yields}{sup 1,3}S and {sup 3}S{sub 1}{yields}{sup 3}D{sub 1}) at short range r{<=}1 fm. As a result, the calculated intrinsic asymmetry parameter {alpha}{sub {lambda}} for {sub {lambda}}{sup 5}He becomes very small and positive in good agreement with the recent high-quality experimental data. The calculated small values of {alpha}{sub {lambda}} are well compared with the data for {sub {lambda}}{sup 11}B and {sub {lambda}}{sup 12}C within error bars. The inclusion of the a{sub 1} meson also improves the {gamma}{sub n}/{gamma}{sub p} ratios and leads to a consistent explanation for the existing nonmesonic weak decay data of the light {lambda} hypernuclei (A{<=}12). The results calculated in the {pi}+2{pi}/{rho}+2{pi}/{sigma}+{omega}+K+{rho}{pi}/a{sub 1}+{sigma}{pi}/a{sub 1} exchange interaction model are presented together with the estimates without a{sub 1}. Also, the derivation of the expression for the proton asymmetry is described in some detail to elucidate the calculation procedures and phase conventions.

Itonaga, K.; Motoba, T.; Ueda, T.; Rijken, Th. A. [Laboratory of Physics, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692 (Japan); Laboratory of Physics, Osaka Electro-communication University, Neyagawa, Osaka 572-8530 (Japan); Arida 1891, Kita-Hiroshima, Hiroshima 731-1533 (Japan); Institute of Mathematics, Astrophysics and Particle Physics, University of Nijmegen (Netherlands)

2008-04-15T23:59:59.000Z

460

Verifying Sensor Response to Difficult Chemicals with a New Test Chamber Concept  

SciTech Connect (OSTI)

In this article we discuss the application of technology innovations to optimize detection of hard-to-measure (less- or semi-volatile) compounds. These chemicals are found all around us: in pesticides and herbicides, the higher boiling polyaromatic hydrocarbons in diesel exhaust, and linked polyurethane foams in products ranging from hiking boots to acoustic ceilings. They appear in low concentrations and evaporate very slowly. These heavier chemicals are rarely measured accurately because they stick to surfaces and sampling equipment and, consequently, are not reliably sampled or delivered to analytical detectors. It’s like trying to identify cold, sticky honey by getting it to flow in through a sampling tube to a detector –it will hardly move. Honey generally coats out on surfaces and sample lines to the extent that even if it is detected, the amount present is vastly underestimated. Researchers at Pacific Northwest National Laboratory (PNNL) addressed the problem by developing a chamber facility with instrumentation that can overcome the under-reporting of these ubiquitous chemical compounds. The atmospheric chemistry chamber provides a controlled environment in which to certify the accuracy of and conditions under which sensors can best respond to volatile and semi-volatile chemicals. The facility is designed to handle and measure chemicals at the levels at which they are found in nature. Test environments can be created in which atmospheric concentrations are at low part-per-trillion concentrations. These concentrations are equivalent to an herbicide off-gassing from a commercially grown apple. The chamber can be set up to simulate releases ranging from industrial vents with high concentrations to releases from surfaces, soils, and/or vegetation where the concentrations are low.

Maughan, A. D.; Birnbaum, Jerome C.; Probasco, Kathleen M.

2004-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Streamer chamber study of intermediate-energy nuclear collisions with CCD cameras  

SciTech Connect (OSTI)

A system of three charge-coupled device (CCD) cameras has been designed and built to record nuclear collisions in a streamer chamber. This technical development significantly enhances the usefulness of streamer chambers as large solid angle ({approx}4{pi} sr) detectors for exclusive measurements in nuclear physics. The system has been used in an experiment designed to study nearly-central collisions of Nb + Nb at 100 and 180 MeV/nucleon. Computer codes have been developed that significantly reduce the amount of operator intervention in the data analysis. One of the most interesting predictions of fluid-dynamical models and VUU calculations for heavy-ion collisions is the sideward emission of nuclear matter, due to the high compression crated during the collision (Stoe 80, Mol 85). The transverse-momentum flow analysis introduced by Danielewicz and Odyniec (Dan 85) allows to calculate the amount of sideward momentum carried by the emitted fragments, while minimizing the distortions caused by finite-multiplicity effects. This momentum flow analysis has been performed on our 180 MeV/nucleon data. The slope of the mean transverse momentum per nucleon vs. rapidity curve at mid-rapidity, or flow, was found to be 47.0 {plus minus} 11.3 MeV/c/nucleon. In order to compare our results to those obtained from other experiments, scale-invariant transverse momentum, p{sup x}, and rapidity, y, have been introduced (Bal 84). The p{sup x} vs. y curve extracted from our data has been compared with the curves obtained for various systems in streamer chamber plus photographic film (Dan 85, Ren 84) and plastic ball experiments (Dos 85), and the shapes have been found to be very similar. The scale-invariant flow, F, for 180 MeV/nucleon Nb + Nb is 0.16 {plus minus} 0.04.

Angius, S.P.

1987-01-01T23:59:59.000Z

462

Study of the calibration of X-T relation for the BESIII drift chamber  

E-Print Network [OSTI]

This paper introduces the calibration of the time-to-distance relation for the BESIII drift chamber. The parameterization of the time-to-distance relation is presented. The studies of left-right asymmetry and the variation with the entrance angle are performed. The impact of dead channels on the time-to-distance relation is given special attention in order to reduce the shifts of the measured momenta for the tracks passing near dead cells. Finally we present the spatial resolution (123 {\\mu}m) for barrel Bhabha events (|cos{\\theta}|data taken in 2012.

Xiao-Lin Kang; Ling-Hui Wu; Zhi Wu; Tao Luo; Chen Hu; Hai-Xai Wang; Shuang-Shi Fang; Kang-Lin He; Wei-Dong Li; Wei-Guo Li; Ze-Pu Mao; Liang-Liang Wang; Ye Yuan; Yao Zhang

2014-05-14T23:59:59.000Z

463

Management of unconverted light for the National Ignition Facility target chamber  

SciTech Connect (OSTI)

The NIF target chamber beam dumps must survive high x-ray, laser, ion, and shrapnel exposures without excessive generation of vapors or particulate that will contaminate the final optics debris shields, thereby making the debris shields susceptible to subsequent laser damage. The beam dumps also must be compatible with attaining and maintaining the required target chamber vacuum and must not activate significantly under high neutron fluxes. Finally, they must be developed, fabricated, and maintained for a reasonable cost. The primary challenge for the beam dump is to survive up to 20 J/cm{sup 2} of lpm light and 1 - 2 J/cm{sup 2} of nominally 200 - 350 eV blackbody temperature x rays. Additional threats include target shrapnel, and other contamination issues. Designs which have been evaluated include louvered hot-pressed boron carbide (B{sub 4}C) or stainless steel (SS) panels, in some cases covered with transparent Teflon film, and various combinations of inexpensive low thermal expansion glasses backed by inexpensive absorbing glass. Louvered designs can recondense a significant amount of ablated material that would otherwise escape into the target chamber. Transparent Teflon was evaluated as an alternative way to capture ablated material. The thin Teflon sheet would need to be replaced after each shot since it exhibits both laser damage and considerable x- ray ablation with each shot. Uncontaminated B{sub 4}C, SS, and low thermal expansion glasses have reasonably small x-ray and laser ablation rates, although the glasses begin to fail catastrophically after 100 high fluence shots. Commercially available absorbing glasses require a pre-shield of either Teflon or low thermal expansion glass to prevent serious degradation by the x-ray fluence. Advantages of the hot-pressed B{sub 4}C and SS over glass are their performance against microshrapnel, their relative indifference to contamination, and their ability to be refurbished by aggressive cleaning using CO{sub 2} pellets, glass beads, high pressure water or ultrasonic tanks. In addition the expected replacement rate to avoid catastrophic failure makes the glass option more costly. SS is less expensive, more easily formed into a louver design with high capture efficiency, and otherwise equivalent to B{sub 4}C. Hence, it would be preferred as long as debris shield damage is not substantially greater for SS as compared to damage from an equivalent mass of contamination of B{sub 4}C. If debris shield damage is problematic, the escape of SS could be mitigated by use of a transparent Teflon film. The Teflon film would require increased target chamber pumping and cleaning capability to accommodate the x-ray decomposition products.

Anderson, A. T.; Bletzer, K.; Burnham, A. K.; Dixit, S; Genin, F. Y.; Hibbard, W.; Norton, J.; Scott, J. M.; Whitman, P. K.

1998-07-08T23:59:59.000Z

464

Development of time projection chamber for precise neutron lifetime measurement using pulsed cold neutron beams  

E-Print Network [OSTI]

A new time projection chamber (TPC) was developed for neutron lifetime measurement using a pulsed cold neutron spallation source at the Japan Proton Accelerator Research Complex (J-PARC). Managing considerable background events from natural sources and the beam radioactivity is a challenging aspect of this measurement. To overcome this problem, the developed TPC has unprecedented features such as the use of polyether-ether-ketone plates in the support structure and internal surfaces covered with $^6$Li-enriched tiles to absorb outlier neutrons. In this paper, the design and performance of the new TPC are reported in detail.

Arimoto, Y; Igarashi, Y; Iwashita, Y; Ino, T; Katayama, R; Kitahara, R; Kitaguchi, M; Matsumura, H; Mishima, K; Oide, H; Otono, H; Sakakibara, R; Shima, T; Shimizu, H M; Sugino, T; Sumi, N; Sumino, H; Taketani, K; Tanaka, G; Tanaka, M; Tauchi, K; Toyoda, A; Yamada, T; Yamashita, S; Yokoyama, H; Yoshioka, T

2015-01-01T23:59:59.000Z

465

Ultrahigh speed 1050nm swept source / Fourier domain OCT retinal and anterior segment imaging at 100,000 to 400,000 axial scans per second  

E-Print Network [OSTI]

We demonstrate ultrahigh speed swept source/Fourier domain ophthalmic OCT imaging using a short cavity swept laser at 100,000 – 400,000 axial scan rates. Several design configurations illustrate tradeoffs in imaging speed, ...

Potsaid, Benjamin M.

466

Hybrid experimental-numerical determination of the loading path to fracture in TRIP780 sheets subjected to multi-axial loading  

E-Print Network [OSTI]

The development of ductile fracture models of metals requires reliable measurements of the stress and strain histories up to the onset of fracture in multi-axial experiments. In the present work, a hybrid experimental-numerical ...

Dunand, Matthieu

2010-01-01T23:59:59.000Z

467

Neutron/gamma dose separation by the multiple-ion-chamber technique  

SciTech Connect (OSTI)

Many mixed n/..gamma.. dosimetry systems rely on two dosimeters, one composed of a tissue-equivalent material and the other made from a non-hydrogenous material. The paired chamber technique works well in fields of neutron radiation nearly identical in spectral composition to that in which the dosimeters were calibrated. However, this technique is drastically compromised in phantom due to the degradation of the neutron spectrum. The three-dosimeter technique allows for the fall-off in neutron sensitivity of the two non-hydrogenous dosimeters. Precise and physically meaningful results were obtained with this technique with a D-T source in air and in phantom and with simultaneous D-T neutron and /sup 60/Co gamma ray irradiation in air. The MORSE-CG coupled n/..gamma.. three-dimensional Monte Carlo code was employed to calculate neutron and gamma doses in a water phantom. Gamma doses calculated in phantom with this code were generally lower than corresponding ion chamber measurements. This can be explained by the departure of irradiation conditions from ideal narrow-beam geometry. 97 references.

Goetsch, S.J.

1983-01-01T23:59:59.000Z

468

Binary reconstruction of the heart chambers from biplane angiographic image sequences  

SciTech Connect (OSTI)

The aim of this work is the three-dimensional (3-D) reconstruction of the left or right heart chamber from digital biplane angiograms. The approach used, the binary reconstruction, exploits the density information of subtracted ventriculograms from two orthogonal views in addition to the ventricular contours. The ambiguity of the problem is largely reduced by incorporating a priori knowledge of human ventricles. A model-based reconstruction program is described that is applicable to routinely acquired biplane ventriculographic studies. Prior to reconstruction, several geometric and densitometric imaging errors are corrected. The finding of corresponding density profiles and anatomical landmarks is supported by a biplane image pairing procedure that takes the movement of the gantry system into account. Absolute measurements are based on geometric isocenter calibration and a slice-wise density calibration technique. The reconstructed ventricles allow 3-D visualization and regional wall motion analysis independently of the gantry setting. The method is applied to clinical angiograms and tested in left- and right-ventricular phantoms yielding a well shape conformity even with few model information. The results indicate that volumes of binary reconstructed ventricles are less projection-dependent compared to volume data derived by purely contour-based methods. A limitations is that the heart chamber must not be superimposed by other dye-filled structures in both projections.

Prause, G.P.M.; Onnasch, D.G.W. [Univ. of Kiel (Germany). Clinic of Pediatric Cardiology] [Univ. of Kiel (Germany). Clinic of Pediatric Cardiology

1996-08-01T23:59:59.000Z

469

Multinuclear and multidimensional solid-state NMR investigations of combustion chamber deposits  

SciTech Connect (OSTI)

Multinuclear solid-state NMR has been used to study the carbonaceous backbone of combustion chamber deposits (CCDs) generated in both gasoline and diesel engines. The combination of {sup 1}H-{sup 13}C cross-polarization, and dipolar dephasing techniques have been used to {open_quotes}average molecule{close_quotes} parameters for a large number of CCDs. These parameters were correlated with gasoline composition and cylinder cleanliness. Discussion will be presented on deposits from different areas of the chamber - piston top, cylinder head, squish, non-squish, end-gas, non-end gas regions. Deposits from various cylinders in a number of dynamometer engines, fleet car engines will be compared. The use of NMR to observe the effects of bench-test engine modifications on CCD structure will be demonstrated. The macromolecular structure of the deposits was studied by {sup 13}C-{sup 13}C spin-exchange experiments which allow one to observe internuclear dipolar interactions between the various carbon functionalities in the deposit. The spatial information on fuel additive - CCD interactions that these experiments provide will be discussed.

Edwards, J.C. [Texaco Research Center, Beacon, NY (United States)

1996-10-01T23:59:59.000Z

470

Progress on an integrated multi-physics simulation predictive capability for plasma chamber nuclear components  

SciTech Connect (OSTI)

Understanding the behavior of a plasma chamber component in the fusion environment requires a simulation technique that is capable of integrating multi-disciplinary computational codes while appropriately treating geometric heterogeneity and complexity. Such a tool should be able to interpret phenomena from mutually dependent scientific disciplines and predict performance with sufficient accuracy and consistency. Integrated multi-physics simulation predictive capability (ISPC) relies upon advanced numerical simulation techniques and is being applied to ITER first wall/shield and Test Blanket Module (TBM) designs. In this paper, progress in ISPC development is described through the presentation of a number of integrated simulations. The simulations cover key physical phenomena encountered in a fusion plasma chamber system, including tritium permeation, fluid dynamics, and structure mechanics. Interface engines were developed in order to pass field data, such as surface deformation or nuclear heating rate, from the structural analysis to the thermo-fluid MHD analysis code for magnetohydrodynamic (MHD) velocity profile assessments, or from the neutronics analysis to the thermo-fluid analysis for temperature calculations, respectively. Near-term effort toward further ISPC development is discussed.

A. Ying; M. Abdou; H. Zhang; R. Munipalli; M. Ulrickson; M. Sawan; B. Merrill

2010-12-01T23:59:59.000Z

471

Construction of a scattering chamber for ion-beam analysis of environmental materials in undergraduate physics research  

SciTech Connect (OSTI)

We have developed a new scattering chamber for ion-beam analysis of environmental materials with the 1.1-MV Pelletron accelerator at the Union College Ion-Beam Analysis Laboratory. The chamber was constructed from a ten-inch, Conflat, multi-port cross and includes a three-axis target manipulator and target ladder assembly, an eight-inch turbo pump, an Amptek X-ray detector, and multiple charged particle detectors. Recent projects performed by our undergraduate research team include proton induced X-ray emission (PIXE) and Rutherford backscattering (RBS) analyses of atmospheric aerosols collected with a nine-stage cascade impactor in Upstate New York. We will describe the construction of the chamber and discuss the results of some commissioning experiments.

LaBrake, Scott M.; Vineyard, Michael F.; Turley, Colin F.; Moore, Robert D.; Johnson, Christopher [Department of Physics and Astronomy Union College, Schenectady, NY 12308 (United States)

2013-04-19T23:59:59.000Z

472

Performance of a Large Area Avalanche Photodiode in a Liquid Xenon Ionization and Scintillation Chamber  

E-Print Network [OSTI]

Scintillation light produced in liquid xenon (LXe) by alpha particles, electrons and gamma-rays was detected with a large area avalanche photodiode (LAAPD) immersed in the liquid. The alpha scintillation yield was measured as a function of applied electric field. We estimate the quantum efficiency of the LAAPD to be 45%. The best energy resolution from the light measurement at zero electric field is 7.5%(sigma) for 976 keV internal conversion electrons from Bi-207 and 2.6%(sigma) for 5.5 MeV alpha particles from Am-241. The detector used for these measurements was also operated as a gridded ionization chamber to measure the charge yield. We confirm that using a LAAPD in LXe does not introduce impurities which inhibit the drifting of free electrons.

K. Ni; E. Aprile; D. Day; K. L. Giboni; J. A. M. Lopes; P. Majewski; M. Yamashita

2005-02-14T23:59:59.000Z

473

Photostructured coating on a voltage degrader for a Time Projection Chamber (TPC)  

E-Print Network [OSTI]

Fibreglass-reinforced epoxy (Stesalit) tubes and rods were coated with a photostructured metal layer system of copper, nickel and gold for a voltage degrader built in a particle detector at CERN, Geneva. The metal layers were applied with galvanotechnical processes involving an original photolithographic exposure in three dimensions to produce a complex electrical circuit design able to provide the correct potential to 420 different conductors. The Stesalit substrate material, even after a first layer of electroless copper, is electrically quite resistive, creating problems for the electrodeposition of the subsequent nickel layer. A mathematical simulation of the plating thickness distribution showed that the electrolytic nickel deposition was suitable for short rods but electroless nickel was needed for the long rods. The functional properties of the metallized Stesalit components are satisfactory: no degradation of the gas quality within the Time Projection Chamber is observed; the potential distribution al...

Manaranche, C; Loquet, J L; Serdiouk, V; Scandurra, M; Zucchelli, P

2002-01-01T23:59:59.000Z

474

Environmental chamber measurements of mercury flux from coal utilization by-products  

SciTech Connect (OSTI)

An environmental chamber was constructed to measure the mercury flux from coal utilization by-product (CUB) samples. Samples of fly ash, FGD gypsum, and wallboard made from FGD gypsum were tested under both dark and illuminated conditions with or without the addition of water to the sample. Mercury releases varied widely, with 7-day experiment averages ranging from -6.8 to 73 ng/m2 h for the fly ash samples and -5.2 to 335 ng/m2 h for the FGD/wallboard samples. Initial mercury content, fly ash type, and light exposure had no observable consistent effects on the mercury flux. For the fly ash samples, the effect of a mercury control technology was to decrease the emission. For three of the four pairs of FGD gypsum and wallboard samples, the wallboard sample released less (or absorbed more) mercury than the gypsum.

Pekney, N.J.; Martello, D.V.; Schroeder, K.T.; Granite, E.J.

2009-05-01T23:59:59.000Z

475

Microbial Community Analysis of a Single Chamber Microbial Fuel Cell Using Potato Wastewater  

SciTech Connect (OSTI)

Microbial fuel cells (MFCs) convert chemical energy to electrical energy via bioelectrochemical reactions mediated by microorganisms. We investigated the diversity of the microbial community in an air cathode single chamber MFC that utilized potato-process wastewater as substrate. Terminal Restriction Fragment Length Polymorphism (T-RFLP) results indicated that the bacterial communities on the anode, cathode, control electrode, and MFC bulk fluid were similar, but differed dramatically from that of the anaerobic domestic sludge and potato wastewater inoculum. The 16S rDNA sequencing results showed that microbial species detected on the anode were predominantly within the phyla of Proteobacteria, Firmicutes, and Bacteroidetes. Fluorescent microscopy results indicated that there was a clear enhancement of biofilm formation on the anode. Results of this study could help improve understanding of the complexity of microbial communities and optimize the microbial composition for generating electricity by MFCs that utilize potato wastewater.

Zhen Li; Rishika Haynes; Eugene Sato; Malcolm Shields; Yoshiko Fujita; Chikashi Sato

2014-04-01T23:59:59.000Z

476

Summary of Previous Chamber or Controlled Anthrax Studies and Recommendations for Possible Additional Studies  

SciTech Connect (OSTI)

This report and an associated Excel file(a) summarizes the investigations and results of previous chamber and controlled studies(b) to characterize the performance of methods for collecting, storing and/or transporting, extracting, and analyzing samples from surfaces contaminated by Bacillus anthracis (BA) or related simulants. This report and the Excel are the joint work of the Pacific Northwest National Laboratory (PNNL) and the National Institute of Standards and Technology (NIST) for the Department of Homeland Security, Science and Technology Directorate. The report was originally released as PNNL-SA-69338, Rev. 0 in November 2009 with limited distribution, but was subsequently cleared for release with unlimited distribution in this Rev. 1. Only minor changes were made to Rev. 0 to yield Rev. 1. A more substantial update (including summarizing data from other studies and more condensed summary tables of data) is underway

Piepel, Gregory F.; Amidan, Brett G.; Morrow, Jayne B.

2010-12-29T23:59:59.000Z

477

Usiing NovoCOS cleaning equipment in repairing the furnace-chamber lining in coke batteries 4 & 5 at OAO Koks  

SciTech Connect (OSTI)

Experience with a new surface-preparation technology for the ceramic resurfacing of the refractory furnace-chamber lining in coke batteries is described.

S.G. Protasov; R. Linden; A. Gross [OAO Koks, Kemerovo (Russian Federation)

2009-05-15T23:59:59.000Z

478

Proposal for the award of a blanket purchase contract, without competitive tendering, for the supply of pressurised ionisation chambers for radiation monitoring  

E-Print Network [OSTI]

Proposal for the award of a blanket purchase contract, without competitive tendering, for the supply of pressurised ionisation chambers for radiation monitoring

2013-01-01T23:59:59.000Z

479

A sonic spark chamber system with on-line computation for studying the reaction $\\pi^{-} + p -> f^{0} + n$ at 3 GeV/c  

E-Print Network [OSTI]

A sonic spark chamber system with on-line computation for studying the reaction $\\pi^{-} + p -> f^{0} + n$ at 3 GeV/c

Bird, L; West, D; Whitehead, G; Wood, E; Crabb, D G; Hutchinson, G W; McEwen, J G; Ott, R; Aitken, D; Hague, J; Jennings, R; Parsons, A J; Auld, E G

1964-01-01T23:59:59.000Z

480

Exit blade geometry and part-load performance of small axial flow propeller turbines: An experimental investigation  

SciTech Connect (OSTI)

A detailed experimental investigation of the effects of exit blade geometry on the part-load performance of low-head, axial flow propeller turbines is presented. Even as these turbines find important applications in small-scale energy generation using micro-hydro, the relationship between the layout of blade profile, geometry and turbine performance continues to be poorly characterized. The experimental results presented here help understand the relationship between exit tip angle, discharge through the turbine, shaft power, and efficiency. The modification was implemented on two different propeller runners and it was found that the power and efficiency gains from decreasing the exit tip angle could be explained by a theoretical model presented here based on classical theory of turbomachines. In particular, the focus is on the behaviour of internal parameters like the runner loss coefficient, relative flow angle at exit, mean axial flow velocity and net tangential flow velocity. The study concluded that the effects of exit tip modification were significant. The introspective discussion on the theoretical model's limitation and test facility suggests wider and continued experimentation pertaining to the internal parameters like inlet vortex profile and exit swirl profile. It also recommends thorough validation of the model and its improvement so that it can be made capable for accurate characterization of blade geometric effects. (author)

Singh, Punit; Nestmann, Franz [Institute for Water and River Basin Management (IWG), University of Karlsruhe, Kaiser Str. 12, D 76128 Karlsruhe (Germany)

2010-09-15T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Experimental Investigation of the Root Cause Mechanism and Effectiveness of Mitigating Actions for Axial Offset Anomaly in Pressurized Water Reactors  

SciTech Connect (OSTI)

Axial offset anomaly (AOA) in pressurized water reactors refers to the presence of a significantly larger measured negative axial offset deviation than predicted by core design calculations. The neutron flux depression in the upper half of high-power rods experiencing significant subcooled boiling is believed to be caused by the concentration of boron species within the crud layer formed on the cladding surface. Recent investigations of the root-cause mechanism for AOA [1,2] suggest that boron build-up on the fuel is caused by precipitation of lithium metaborate (LiBO2) within the crud in regions of subcooled boiling. Indirect evidence in support of this hypothesis was inferred from operating experience at Callaway, where lithium return and hide-out were, respectively, observed following power reductions and power increases when AOA was present. However, direct evidence of lithium metaborate precipitation within the crud has, heretofore, not been shown because of its retrograde solubility. To this end, this investigation has been undertaken in order to directly verify or refute the proposed root-cause mechanism of AOA, and examine the effectiveness of possible mitigating actions to limit its impact in high power PWR cores.

Said Abdel-Khalik

2005-07-02T23:59:59.000Z

482

Status of axial heterogeneous liquid-metal fast breeder reactor core design studies and research and development  

SciTech Connect (OSTI)

The current status of axial heterogeneous core (AHC) design development in Japan, which consists of an AHC core design in a pool-type demonstration fast breeder reactor (DFBR) and research and development activities supporting AHC core design, is presented. The DFBR core design objectives developed by The Japan Atomic Power Company include (a) favorable core seismic response, (b) core compactness, (c) high availability, and (d) lower fuel cycle cost. The AHC concept was selected as a reference pool-type DFBR core because it met these objectives more suitably than the homogeneous core (HOC). The AHC core layouts were optimized emphasizing the reduction of the burnup reactivity swing, peak fast fluence, and power peaking. The key performance parameters resulting from the AHC, such as flat axial power/flux distribution, lower peak fast fluence, lower burnup reactivity swing, etc., were evaluated in comparison with the HOC. The critical experiments at the Japan Atomic Energy Research Institute's Fast Critical Assembly facility demonstrate the key AHC performance characteristics. The large AHC engineering benchmark experiments using the zero-power plutonium reactor and the AHC fuel pin irradiation test program using the JOYO reactor are also presented.

Nakagawa, H.; Inagaki, T.; Yoshimi, H.; Shirakata, K.; Watari, Y.; Suzuki, M.; Inoue, K.

1988-11-01T23:59:59.000Z

483

2014 National Small Business Contracting Summit- US Women’s Chamber of Commerce & National Association of Small Business Contractors  

Broader source: Energy.gov [DOE]

The National Association of Small Business Contractors and the U.S. Women's Chamber of Commerce present the 2014 National Small Business Federal Contracting Summit. The event will include sessions on securing a fair share of federal contracting, legal issues, trends and opportunities.

484

Time-course correlation of biofilm properties and electrochemical performance in single-chamber microbial fuel cells  

E-Print Network [OSTI]

-chamber microbial fuel cells Zhiyong Ren a,c , Ramaraja P. Ramasamy b,1 , Susan Red Cloud-Owen b , Hengjing Yan 2010 Keywords: Microbial fuel cell Electricity Biofilm Electrochemical impedance spectroscopy a b s t r in microbial fuel cells (MFCs) was analyzed by time-course sampling of parallel single-bottle MFCs operated

Mench, Matthew M.

485

A Geographic Redirection Service for On-line Games Chris Chambers Wu-chi Feng Wu-chang Feng  

E-Print Network [OSTI]

@OHSU {chambers,wuchi,wuchang}@cse.ogi.edu Debanjan Saha IBM Research dsaha@us.ibm.com ABSTRACT For many on Shooters, fre- quently utilize a widely distributed server model. For the most popular FPS at this time, Counter-Strike (a variant of Half-Life), there are more than 30,000 registered servers running at any

486

ARIES Inertial Fusion Chamber Assessment M. S. Tillack*, F. Najmabadi, L. A. El-Guebaly, D. Goodin, W. R. Meier,  

E-Print Network [OSTI]

-coupled indirect drive and fast ignition. Arguably, inertial fusion looks significantly more credible and more components (i.e., final optics, final focus magnets), chamber physics (particle and radiation transport, gas al., "Inertial Fusion Energy Reactor Design Studies: Prometheus Final Report," MDC 92E0008 (DOE

California at San Diego, University of

487

Methane Emissions from a Small Wind Shielded Lake Determined by Eddy Covariance, Flux Chambers, Anchored Funnels, and Boundary  

E-Print Network [OSTI]

Methane Emissions from a Small Wind Shielded Lake Determined by Eddy Covariance, Flux Chambers of methane, held to be responsible for 18% of the radiative forcing, to the atmosphere. Periods of lake but potentially one of the most important periods for methane emissions. We studied methane emissions using four

Wehrli, Bernhard

488

A Concept for a Low Pressure Noble Gas Fill Intervention in the IFE Fusion Test Facility (FTF) Target Chamber  

SciTech Connect (OSTI)

An engineering evaluation has been initiated to investigate conceptual engineering methods for implementing a viable gas shield strategy in the Fusion Test Facility (FTF) target chamber. The employment of a low pressure noble gas in the target chamber to thermalize energetic helium ions prior to interaction with the wall could dramatically increase the useful life of the first wall in the FTF reactor1. For the purpose of providing flexibility, two target chamber configurations are addressed: a five meter radius sphere and a ten meter radius sphere. Experimental studies at Nike have indicated that a low pressure, ambient gas resident in the target chamber during laser pulsing does not appear to impair the ability of laser light from illuminating targets2. In addition, current investigations into delivering, maintaining, and processing low pressure gas appear to be viable with slight modification to current pumping and plasma exhaust processing technologies3,4. Employment of a gas fill solution for protecting the dry wall target chamber in the FTF may reduce, or possibly eliminate the need for other attenuating technologies designed for keeping He ions from implanting in first wall structures and components. The gas fill concept appears to provide an effective means of extending the life of the first wall while employing mostly commercial off the shelf (COTS) technologies. Although a gas fill configuration may provide a methodology for attenuating damage inflicted on chamber surfaces, issues associated with target injection need to be further analyzed to ensure that the gas fill concept is viable in the integrated FTF design5. In the proposed system, the ambient noble gas is heated via the energetic helium ions produced by target detonation. The gas is subsequently cooled by the chamber wall to approximately 800oC, removed from the chamber, and processed by the chamber gas processing system (CGPS). In an optimized scenario of the above stated concept, the chamber wall acts as the primary heat exchanger. During removal, gas is pumped through the laser ports by turbo molecular-drag pumps (TM-DP). For the purpose of reducing organic based lubricants and seals, a magnetically levitated TM-DP is being investigated with pump manufacturers. Currently, magnetically levitated turbo molecular pumps are commercially available. The pumps will be exposed to thermal loads and ionizing radiation (tritium, Ar-41, post detonation neutrons). Although the TM-DP's will be subjected to these various radiations, current designs for similar pumping devices have been hardened and have the ability of locating control electronics in remote radiation shielded enclosures4. The radiation hardened TM-DP's will be 5 required to operate with minimal maintenance for periods of up to 18 continuous months. As part of this initial investigation for developing a conceptual engineering strategy for a gas fill solution, commercial suppliers of low pressure gas pumping systems have been contacted and engaged in this evaluation. Current technology in the area of mechanical pumping systems indicates that the development of a robust pumping system to meet the requirements of the FTF gas fill concept is within the limits of COTS equipment3,4.

C.A. Gentile, W.R. Blanchard, T.A. Kozub, M. Aristova, C. McGahan, S. Natta, K. Pagdon, J. Zelenty

2010-01-14T23:59:59.000Z

489

Axial magnetic field and toroidally streaming fast ions in the dense plasma focus are natural consequences of conservation laws in the curved axisymmetric geometry of the current sheath  

E-Print Network [OSTI]

Direct measurement of axial magnetic field in the PF-1000 dense plasma focus (DPF), and its reported correlation with neutron emission, call for a fresh look at previous reports of existence of axial magnetic field component in the DPF from other laboratories, and associated data suggesting toroidal directionality of fast ions participating in fusion reactions, with a view to understand the underlying physics. In this context, recent work dealing with application of the hyperbolic conservation law formalism to the DPF is extended in this paper to a curvilinear coordinate system, which reflects the shape of the DPF current sheath. Locally-unidirectional shock propagation in this coordinate system enables construction of a system of 7 one-dimensional hyperbolic conservation law equations with geometric source terms, taking into account all the components of magnetic field and flow velocity. Rankine-Hugoniot jump conditions for this system lead to expressions for the axial magnetic field and three components of ...

Auluck, S K H

2014-01-01T23:59:59.000Z

490

Nickel based anodes for single chamber solid oxide fuel cells : a catalytic study Geoffroy Gadacz, Sorina Udroiu, Jean-Paul Viricelle, Christophe Pijolat, Michle Pijolat  

E-Print Network [OSTI]

Nickel based anodes for single chamber solid oxide fuel cells : a catalytic study Geoffroy Gadacz Single chamber solid oxide fuel cells (SCFC) are an alternative concept to traditional SOFC-gas-shift equilibrium. Introduction Fifteen years ago, Hibino (1) has shown the feasibility of a fuel cell consisting

Boyer, Edmond

491

Neutron tomography of axially symmetric objects using 14 MeV neutrons from a portable neutron generator  

SciTech Connect (OSTI)

In nuclear boiling water reactor cores, the distribution of water and steam (void) is essential for both safety and efficiency reasons. In order to enhance predictive capabilities, void distribution assessment is performed in two-phase test-loops under reactor-relevant conditions. This article proposes the novel technique of fast-neutron tomography using a portable deuterium-tritium neutron generator to determine the time-averaged void distribution in these loops. Fast neutrons have the advantage of high transmission through the metallic structures and pipes typically concealing a thermal-hydraulic test loop, while still being fairly sensitive to the water/void content. However, commercially available fast-neutron generators also have the disadvantage of a relatively low yield and fast-neutron detection also suffers from relatively low detection efficiency. Fortunately, some loops are axially symmetric, a property which can be exploited to reduce the amount of data needed for tomographic measurement, thus limiting the interrogation time needed. In this article, three axially symmetric test objects depicting a thermal-hydraulic test loop have been examined; steel pipes with outer diameter 24 mm, thickness 1.5 mm, and with three different distributions of the plastic material POM inside the pipes. Data recorded with the FANTOM fast-neutron tomography instrument have been used to perform tomographic reconstructions to assess their radial material distribution. Here, a dedicated tomographic algorithm that exploits the symmetry of these objects has been applied, which is described in the paper. Results are demonstrated in 20 rixel (radial pixel) reconstructions of the interior constitution and 2D visualization of the pipe interior is demonstrated. The local POM attenuation coefficients in the rixels were measured with errors (RMS) of 0.025, 0.020, and 0.022 cm{sup ?1}, solid POM attenuation coefficient. The accuracy and precision is high enough to provide a useful indication on the flow mode, and a visualization of the radial material distribution can be obtained. A benefit of this system is its potential to be mounted at any axial height of a two-phase test section without requirements for pre-fabricated entrances or windows. This could mean a significant increase in flexibility of the void distribution assessment capability at many existing two-phase test loops.

Andersson, P., E-mail: peter.andersson@physics.uu.se; Andersson-Sunden, E.; Sjöstrand, H.; Jacobsson-Svärd, S. [Department of Physics and Astronomy, Division of Applied Nuclear Physics, Uppsala University, Lägerhyddsgatan 1, 751 20 Uppsala (Sweden)

2014-08-01T23:59:59.000Z

492

1059-9630/$19.00 Ó ASM International Effective Parameters in Axial Injection Suspension Plasma Spray Process  

E-Print Network [OSTI]

Suspension plasma spray (SPS) is a novel process for producing nano-structured coatings with metastable phases using significantly smaller particles as compared to conventional thermal spraying. Considering the complexity of the system there is an extensive need to better understand the relationship between plasma spray conditions and resulting coating microstructure and defects. In this study, an alumina/ 8 wt. % yttria-stabilized zirconia was deposited by axial injection SPS process. The effects of principal deposition parameters on the microstructural features are evaluated using the Taguchi design of experiment. The microstructural features include microcracks, porosities, and deposition rate. To better understand the role of the spray parameters, in-flight particle characteristics, i.e., temperature and velocity were also measured. The role of the porosity in this multicomponent structure is studied as well. The results indicate that thermal diffusivity of the coatings, an important property for potential thermal barrier applications, is barely affected by the changes in porosity content.

Of Alumina-zirconia Ceramics; F. Tarasi; M. Medraj; A. Dolatabadi; J. Oberste-berghaus; C. Moreau; Peer Reviewed

2008-01-01T23:59:59.000Z

493

Shell model study of $^{40}$Ca muon capture and the $(0^+, 0)$$\\to$$(0^-, 2626)$ axial charge transition  

E-Print Network [OSTI]

We report results from shell model studies of muon capture on $^{40}$Ca to low-lying levels of $^{40}$K. We discuss the comparison between calculated capture rates, measured capture rates and analogous transitions in ($e$,$e^{\\prime}$) scattering in terms of the particle-hole structure of the $^{40}$Ca-$^{40}$K nuclei. We highlight the $^{40}$Ca$(0^+, 0)$$\\to$$^{40}$K$(0^-, 2626)$ axial charge transition and its sensitivity to the induced pseudoscalar coupling $g_p$ of the proton's weak interaction. In addition, we address the hindrance of unique first-forbidden transitions due to particle-hole interactions and the emergence of allowed Gamow-Teller transitions due to ground state correlations. Lastly, we examine the longitudinal alignment of $^{40}$K recoils following muon capture, and discuss this possibility for independently determining the induced coupling $g_p$.

T. P. Gorringe

2006-06-14T23:59:59.000Z

494

Two-dimensional simulations of thermonuclear burn in ignition-scale inertial confinement fusion targets under compressed axial magnetic fields  

SciTech Connect (OSTI)

We report for the first time on full 2-D radiation-hydrodynamic implosion simulations that explore the impact of highly compressed imposed magnetic fields on the ignition and burn of perturbed spherical implosions of ignition-scale cryogenic capsules. Using perturbations that highly convolute the cold fuel boundary of the hotspot and prevent ignition without applied fields, we impose initial axial seed fields of 20–100 T (potentially attainable using present experimental methods) that compress to greater than 4 × 10{sup 4} T (400 MG) under implosion, thereby relaxing hotspot areal densities and pressures required for ignition and propagating burn by ?50%. The compressed field is high enough to suppress transverse electron heat conduction, and to allow alphas to couple energy into the hotspot even when highly deformed by large low-mode amplitudes. This might permit the recovery of ignition, or at least significant alpha particle heating, in submarginal capsules that would otherwise fail because of adverse hydrodynamic instabilities.

Perkins, L. J.; Logan, B. G.; Zimmerman, G. B.; Werner, C. J. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)] [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2013-07-15T23:59:59.000Z

495

Cylindrically confined pair-ion-electron and pair-ion plasmas having axial sheared flow and radial gradients  

SciTech Connect (OSTI)

The linear and nonlinear dynamics of pair-ion (PI) and pair-ion-electron plasmas (PIE) have been investigated in a cylindrical geometry with a sheared plasma flow along the axial direction having radial dependence. The coupled linear dispersion relation of low frequency electrostatic waves has been presented taking into account the Guassian profile of density and linear gradient of sheared flow. It is pointed out that the quasi-neutral cold inhomogeneous pure pair ion plasma supports only the obliquely propagating convective cell mode. The linear dispersion relation of this mode has been solved using boundary conditions. The nonlinear structures in the form of vortices formed by different waves have been discussed in PI and PIE plasmas.

Batool, Nazia; Saleem, H. [National Centre for Physics (NCP), Quaid-i-Azam University Campus, Islamabad (Pakistan)] [National Centre for Physics (NCP), Quaid-i-Azam University Campus, Islamabad (Pakistan)

2013-10-15T23:59:59.000Z

496

Exact analysis of particle dynamics in combined field of finite duration laser pulse and static axial magnetic field  

SciTech Connect (OSTI)

Dynamics of a charged particle is studied in the field of a relativistically intense linearly polarized finite duration laser pulse in the presence of a static axial magnetic field. For a finite duration laser pulse whose temporal shape is defined by Gaussian profile, exact analytical expressions are derived for the particle trajectory, momentum, and energy as function of laser phase. From the solutions, it is shown that, unlike for the monochromatic plane wave case, resonant phase locking time between the particle and laser pulse is finite. The net energy transferred to the particle does not increase monotonically but tends to saturate. It is further shown that appropriate tuning of cyclotron frequency of the particle with the characteristic frequency in the pulse spectrum can lead to the generation of accelerated particles with variable energies in MeV-TeV range.

Sagar, Vikram; Sengupta, Sudip; Kaw, Predhiman [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

2012-11-15T23:59:59.000Z

497

Method for determining liquid recovery during a closed-chamber drill stem test  

SciTech Connect (OSTI)

This patent describes a method for determining a rate of production of well fluid produced during a closed chamber drill stem test of a subterranean formation. It comprises generating an acoustic signal capable of propagating down a well containing a drill stem test tubing; measuring a travel time of an acoustic signal reflected from an identifiable reference point in the drill stem test tubing; flowing the subterranean formation a predetermined length of time; measuring a travel time of an acoustic signal reflected from a liquid level in the drill stem test tubing during the flow interval; shutting in the flow of the subterranean formation; determining a volume of liquid produced during the flow interval based on the travel time of the reflected acoustic signal; determining a total amount of well fluid produced during the flow interval based on the volume of fluid produced and the surface pressure measurements during the flow period; and determining the rate of production from the subterranean formation during the flow period.

Finley, D.B.; Bass, A.O.

1992-03-03T23:59:59.000Z

498

S$?$RIT: A time-projection chamber for symmetry-energy studies  

E-Print Network [OSTI]

A Time-Projection Chamber (TPC) called the SAMURAI Pion-Reconstruction and Ion-Tracker (S$\\pi$RIT) has recently been constructed at Michigan State University as part of an international effort to constrain the symmetry-energy term in the nuclear Equation of State (EoS). The S$\\pi$RIT TPC will be used in conjunction with the SAMURAI spectrometer at the Radioactive Isotope Beam Factory (RIBF) at RIKEN to measure yield ratios for pions and other light isospin multiplets produced in central collisions of neutron-rich heavy ions, such as $^{132}$Sn + $^{124}$Sn. The S$\\pi$RIT TPC can function both as a TPC detector and as an active target. It has a vertical drift length of 50 cm, parallel to the magnetic field. Gas multiplication is achieved through the use of a multi-wire anode. Image charges are produced in the 12096 pads, and are read out with the recently developed Generic Electronics for TPCs.

R. Shane; A. McIntosh; T. Isobe; W. G. Lynch; H. Baba; J. Barney; Z. Chajecki; M. Chartier; J. Estee; M. Famiano; B. Hong; K. Ieki; G. Jhang; R. Lemmon; F. Lu; T. Murakami; N. Nakatsuka; M. Nishimura; R. Olsen; W. Powell; H. Sakurai; A. Taketani; S. Tangwancharoen; M. B. Tsang; T. Usukura; R. Wang; S. J. Yennello; J. Yurkon

2014-09-22T23:59:59.000Z

499

Feasibility of microwave-produced Bragg reflector: Examined by the chamber experiment  

SciTech Connect (OSTI)

A set of parallel plasma layers is generated by two intersecting microwave pulses in a chamber containing dry air at a pressure comparable to the upper atmosphere. The dependencies of breakdown conditions on the pressure and pulse length are examined. The results are shown to be consistent with the appearance of tad erosion of microwave pulse caused by air breakdown. A Bragg scattering experiment, using the plasma layers as a Bragg reflector is then performed. Both time domain and frequency domain measurements of wave scattering are conducted. ne experiment results are found to agree very well with the theory. Moreover, the time domain measurement of wave scattering provides an unambiguous way for determining the temporal evolution of electron density during the first IMP period. A Langmuir double probe is also used to determine the decay rate of electron density during a later time interval (I ms to 1.1 ms). The propagation of high power microwave pulses through the air is also studied experimentally. The mechanisms responsible for two different degree of tail erosion have been identified. The optimum amplitude of an 1. 1us pulse for maximum energy transfer through the air has been determined.

Kuo, S.P.; Zhang, Y.S.

1990-10-01T23:59:59.000Z

500

Inhalation toxicology of red and violet mixtures. Chamber concentration and particle-size distribution report  

SciTech Connect (OSTI)

An inhalation exposure facility was developed at the U.S. EPA, RTP, NC to conduct inhalation exposures of rodents and guinea pigs to dye mixtures used by the U.S. Army in the manufacture of smoke munitions. Initially, an evaluation of the prototype chamber aerosol homogeneity was conducted to determine the uniformity and reproducibility of the concentration and particle size of dye aerosol throughout the breathing zone of the test animals. The three dyes, DR11, SR1, and DB3, were chemically analyzed for purity and optically examined for size and shape. All pure dyes appeared to be stable at room temperature except DB3, which decomposes if not stored at 4 C. The particle size ranges varied for each pure dye and structures were either amorphous (azo dye) or crystalline (anthraquinone dyes). The bulk red and violet dye mixtures were analyzed for composition. The chemical analysis of the relative composition of each dye mixture, collected by cascade impactor sampling, revealed fractionation of the mixtures into component dyes.

Higuchi, M.A.; Davies, D.W.

1991-07-01T23:59:59.000Z