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1

Geologic evidence for a magma chamber beneath Newberry Volcano, Oregon  

SciTech Connect

At Newberry Volcano, central Oregon, more than 0.5 m.y. of magmatic activity, including caldera collapse and renewed caldera-filling volcanism, has created a structural and thermal chimney that channels magma ascent. Holocene rhyolitic eruptions (1) have been confined mainly within the caldera in an area 5 km in diameter, (2) have been very similar in chemical composition, phenocryst mineralogy, and eruptive style, and (3) have occurred as recently as 1300 years ago, with repose periods of 2000--3000 years between eruptions. Holocene basaltic andesite eruptions are widespread on the flanks but are excluded from the area of rhyolitic volcanism. Basaltic andesite in fissures at the edge of the rhyolite area has silicic inclusions and shows mixed basalt-rhyolite magma relations. These geologic relations and the high geothermal gradient that characterizes the lower part of a drill hole in the caldera (U.S. Geological Survey Newberry 2) indicate that a rhyolitic magma chamber has existed beneath the caldera throughout the Holocene. Its longevity probably is a result of intermittent underplating by basaltic magma.

Macleod, N.S.; Sherrod, D.R.

1988-09-10T23:59:59.000Z

2

Aging in the large CDF axial drift chamber  

DOE Green Energy (OSTI)

The Central Outer Tracker (COT) is a large axial drift chamber in the Collider Detector at Fermilab operating with a gas mixture that is 50/50 argon/ethane with an admixture of 1.7% isopropanol. In its first two years of operation the COT showed unexpected aging with the worst parts of the chamber experiencing a gain loss of {approx}50% for an accumulated charge of {approx}35 mC/cm. By monitoring the pulse height of hits on good tracks, it was possible to determine the gain as a function of time and location in the chamber. In addition, the currents of the high voltage supplies gave another monitor of chamber gain and its dependence on the charge deposition rate. The aging was worse on the exhaust end of the chamber consistent with polymer buildup as the gas flows through the chamber. The distribution in azimuth suggests that aging is enhanced at lower temperatures, but other factors such as gas flow patterns may be involved. Elemental and molecular analysis of the sense wires found a coating that is mostly carbon and hydrogen with a small amount of oxygen; no silicon or other contaminants were identified. High resolution electron microscope pictures of the wire surface show that the coating is smooth with small sub-micron nodules. In the course of working with the chamber gas system, we discovered a small amount of O{sub 2} is enough to reverse the aging. Operating the chamber with {approx}100 ppm of O{sub 2} reversed almost two years of gain loss in less than 10 days while accumulating {le} 2 mC/cm.

Allspach, D.; Ambrose, D.; Binkley, M.; /Fermilab; Bromberg, C.; /Michigan State U.; Burkett, K.; Kephart, R.; Madrak, R.; Miao, T.; Mukherjee, A.; Roser, R.; Wagner, R.L. /Fermilab

2004-12-01T23:59:59.000Z

3

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

Open Energy Info (EERE)

Evidence For A Hydrothermal Layer Above The Solid Roof Of The Axial Evidence For A Hydrothermal Layer Above The Solid Roof Of The Axial Magma Chamber At The Southern East Pacific Rise Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Seismic Evidence For A Hydrothermal Layer Above The Solid Roof Of The Axial Magma Chamber At The Southern East Pacific Rise Details Activities (1) Areas (1) Regions (0) Abstract: A full-waveform inversion of two-ship, wide-aperture, seismic reflection data from a ridge-crest seismic line at the southern East Pacific Rise indicates that the axial magma chamber here is about 50 m thick, is embedded within a solid roof, and has a solid floor. The 50-60-m-thick roof is overlain by a 150-200-m-thick low-velocity zone that may correspond to a fracture zone that hosts the hydrothermal circulation,

4

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

DOE Green Energy (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

5

Energy extraction from crustal magma bodies  

DOE Green Energy (OSTI)

An open heat exchanger system for extracting thermal energy directly from shallow crustal magma bodies is described. The concept relies on natural properties of magma to create a permeable, solidified region surrounding a borehole drilled into the magma chamber. The region is fractured, possessing large surface area, and is sealed from the overburden. Energy is extracted by circulating a fluid through the system. Thermal stress analysis shows that such a fractured region can be developed at depths up to 10 km. An open heat exchanger experiment conducted in the partial melt zone of Kilauea Iki lava lake demonstrated the validity of this concept. Effective heat transfer surface area an order of magnitude greater than the borehole area was established during a two-day test period. The open heat exchanger concept greatly extends the number of magma systems that can be economically developed to produce energy.

Dunn, J.C.

1982-01-01T23:59:59.000Z

6

Magma benchmark code - CECM  

E-Print Network (OSTI)

Below is the Magma code used to run the benchmarks in Section 5 of the paper " In-place Arithmetic for Univariate Polynomials over an Algebraic Number Field"...

7

Magma Source Location Survey  

DOE Green Energy (OSTI)

A survey of Industry/University geophysicists was conducted to obtain their opinions on the existence of shallow (less than 10 km from surface) magma bodies in the western conterminous United States and methods for locating and defining them. Inputs from 35 individuals were received and are included. Responses were that shallow magma bodies exist and that existing geophysical sensing systems are adequate to locate them.

Hardee, H.C.; Dunn, J.C.; Colp, J.L.

1982-03-01T23:59:59.000Z

8

Magma energy for power generation  

DOE Green Energy (OSTI)

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

Dunn, J.C.

1987-01-01T23:59:59.000Z

9

Magma energy: a feasible alternative  

DOE Green Energy (OSTI)

A program to investigate the scientific feasibility of extracting energy directly from deeply buried circulating magma sources is described. The following program tasks are discussed: source location and definition, source tapping, magma characterization, magma/material compatibility, and energy extraction. (MHR)

Colp, J.L.

1979-01-01T23:59:59.000Z

10

Magma energy: a feasible alternative  

DOE Green Energy (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

11

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

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 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

13

Magma Energy | Open Energy Information  

Open Energy Info (EERE)

Magma Energy Magma Energy Name Magma Energy Address 5500 Soda Lake Road Place Fallon, NV Zip 89406 Sector Geothermal energy Phone number 775.867.5093 Website http://www.alterrapower.ca References Alterra Power Corp[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! Magma Energy is a subsidiary of Alterra Power based in Fallon, Nevada. Alterra Power Corp. is a leading global renewable energy company. Alterra operates six power plants totaling 566 MW of capacity, including two geothermal facilities in Iceland, a geothermal plant in Nevada, British Columbia's largest run of river hydro facilities and the province's largest wind farm. Their 297 MW share of production capacity generates approximately 1,400 GWh of clean power annually. Alterra has an extensive

14

Exposure chamber  

DOE Patents (OSTI)

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

Moss, Owen R. (Kennewick, WA)

1980-01-01T23:59:59.000Z

15

Wire chamber  

DOE Patents (OSTI)

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

Atac, Muzaffer (Wheaton, IL)

1989-01-01T23:59:59.000Z

16

IONIZATION CHAMBER  

DOE Patents (OSTI)

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

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

1958-02-18T23:59:59.000Z

17

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

18

Shallow magma targets in the western US  

DOE Green Energy (OSTI)

Within the next few years a hole will be drilled into a shallow magma body in the western US for the purpose of evaluating the engineering feasibility of magma energy. This paper examines potential drilling sites for these engineering feasibility experiments. Target sites high on the list are ones that currently exhibit good geophysical and geological data for shallow magma and also have reasonable operational requirements. Top ranked sites for the first magma energy well are Long Valley, CA, and Coso/Indian Wells, CA. Kilauea, HI, also in the top group, is an attractive site for some limited field experiments. A number of additional sites offer promise as eventual magma energy sites, but sparsity of geophysical data presently prevents these sites from being considered for the first magma energy well.

Hardee, H.C.

1984-10-01T23:59:59.000Z

19

Recent progress in magma energy extraction  

DOE Green Energy (OSTI)

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

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

1987-01-01T23:59:59.000Z

20

Magma energy and geothermal permeability enhancement programs  

DOE Green Energy (OSTI)

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

Dunn, J.C.

1985-01-01T23:59:59.000Z

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.


21

Magma Energy Research Project, FY80 annual progress report  

SciTech Connect

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

22

Chamber propagation  

SciTech Connect

Propagation of a heavy ion beam to the target appears possible under conditions thought to be realizable by several reactor designs. Beam quality at the lens is believed to provide adequate intensity at the target -- but the beam must pass through chamber debris and its self fields along the way. This paper reviews present consensus on propagation modes and presents recent results on the effects of photoionization of the beam ions by thermal x-rays from the heated target. Ballistic propagation through very low densities is a conservative mode. The more-speculative self-pinched mode, at 1 to 10 Torr, offers reactor advantages and is being re-examined by others. 13 refs.

Langdon, B.

1991-01-16T23:59:59.000Z

23

Process for forming hydrogen and other fuels utilizing magma  

DOE Patents (OSTI)

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

Galt, John K. (Albuquerque, NM); Gerlach, Terrence M. (Albuquerque, NM); Modreski, Peter J. (Albuquerque, NM); Northrup, Jr., Clyde J. M. (Albuquerque, NM)

1978-01-01T23:59:59.000Z

24

Glossary Term - Cloud Chamber  

NLE Websites -- All DOE Office Websites (Extended Search)

Ceres Previous Term (Ceres) Glossary Main Index Next Term (Composition of the Earth's Atmosphere) Composition of the
Earth's Atmosphere Cloud Chamber A cloud chamber showing the...

25

Status of the Magma Energy Project  

DOE Green Energy (OSTI)

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

Dunn, J.C.

1987-01-01T23:59:59.000Z

26

Final report - Magma Energy Research Project  

DOE Green Energy (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

Magma Energy Research, 79-1. Semiannual report, October 1, 1978-March 31, 1979  

DOE Green Energy (OSTI)

A major effort in evaluating Kilauea Iki lava lake has been completed. The physical model based on FY 76 geophysical experiments is not correct in that a low viscosity, liquid lens of appreciable thickness does not exist. Mathematical models of the cooling of the lava lake and the state of solidification of the liquid lens were verified by thermal profile and permeability measurements. New jet-augmented drilling concepts successfully penetrated the viscous, multi-phase molten rock region in some locations where conventional drilling failed. Heat transfer studies in the lake suggest injection of fluids to enhance convection may be useful to extract energy from magma chamber margins. Other activities resulted in the completion and successful testing of a 800 cc simulation facility for evaluating simulated magma properties at temperatures to 1500/sup 0/C and pressures to 4 kbar. In materials compatibility studies, thermodynamic stability diagrams were developed for 15 pure metals in basaltic magma systems and compatibility tests completed. Results are being used to define simple alloy systems which may be compatible with magmas and to identify other superalloy materials candidates.

Traeger, R.K.; Colp, J.L.; Neel, R.R. (eds.)

1979-07-01T23:59:59.000Z

28

ILLUMINATION OF 80-INCH BUBBLE CHAMBER  

SciTech Connect

A cylindrical condensing system whose geometry allows light to be collected along the length of narrow tubular sources and to pass through a restricted port area is used. The quantity of light collected is many times that possible to obtain with axially symmetric lenses. The optical arrangement is described. Other unique features include the use of plano reilectors to extend optically the flash tube and condenser lengths and the provision of a spot plate to eliminate surface reflections from the chamber window. (auth)

Rosin, S.

1962-01-01T23:59:59.000Z

29

Utilization of magma energy: a project summary  

DOE Green Energy (OSTI)

The scientific feasibility of extracting energy from magma bodies is the objective of this project. The high temperature (approx. 1000/sup 0/C) and estimated large resource (approx. 10/sup 4/ quads) within 10 km of the surface in the US provides the incentive for this work. The areal extent of a near-surface molten lava body has been defined with geophysical sensing systems. Improved knowledge of the in situ physical properties of buried molten rock is required to assess the thickness of magma bodies. Drilling into molten lava is a complex operation and requires further technological development. Experimental studies of rock deformation at near-magma temperatures and pressures show that boreholes can be made to stay open. Calculational analyses of magmatic gas samples provide a satisfactory definition of the gas content of in situ magmas. Material compatibility experiments show that Ni- and Co-based alloys can survive and operate in the magma environment. Thermal heat exchangers can survive in molten rock and allow significant rates of heat transfer to an internal fluid.

Colp, J.L.; Stoller, H.M.

1979-09-01T23:59:59.000Z

30

Geology of magma systems: background and review  

DOE Green Energy (OSTI)

A review of basic concepts and current models of igneous geology is presented. Emphasis is centered on studies of magma generation, ascent, emplacement, evolution, and surface or near-surface activity. An indexed reference list is also provided to facilitate future investigations.

Peterfreund, A.R.

1981-03-01T23:59:59.000Z

31

Unusual Iron Redox Systematics of Martian Magmas  

SciTech Connect

Martian magmas are known to be FeO-rich and the dominant FeO-bearing mineral at many sites visited by the Mars Exploration rovers (MER) is magnetite. Morris et al. proposed that the magnetite appears to be igneous in origin, rather than of secondary origin. However, magnetite is not typically found in experimental studies of martian magmatic rocks. Magnetite stability in terrestrial magmas is well understood, as are the stabilities of FeO and Fe{sub 2}O{sub 3} in terrestrial magmas. In order to better understand the variation of FeO and Fe{sub 2}O{sub 3}, and the stability of magnetite (and other FeO-bearing phases) in martian magmas, we have undertaken an experimental study with two emphases. First, we determine the FeO and Fe{sub 2}O{sub 3} contents of super- and sub-liquidus glasses from a shergottite bulk composition at 1 bar to 4 GPa, and variable fO{sub 2}. Second, we document the stability of magnetite with temperature and fO{sub 2} in a shergottite bulk composition.

Danielson, L.; Righter, K.; Pando, K.; Morris, R.V.; Graff, T.; Agresti, D.; Martin, A.; Sutton, S.; Newville, M.; Lanzirotti, A. (NASA-JSC); (ESCG Jacobs); (UAB); (UC)

2012-03-26T23:59:59.000Z

32

Numerical simulation of magma energy extraction  

DOE Green Energy (OSTI)

The Magma Energy Program is a speculative endeavor regarding practical utility of electrical power production from the thermal energy which reside in magma. The systematic investigation has identified an number of research areas which have application to the utilization of magma energy and to the field of geothermal energy. Eight topics were identified which involve thermal processes and which are areas for the application of the techniques of numerical simulation. These areas are: (1) two-phase flow of the working fluid in the wellbore, (2) thermodynamic cycles for the production of electrical power, (3) optimization of the entire system, (4) solidification and fracturing of the magma caused by the energy extraction process, (5) heat transfer and fluid flow within an open, direct-contact, heat-exchanger, (6) thermal convection in the overlying geothermal region, (7) thermal convection within the magma body, and (8) induced natural convection near the thermal energy extraction device. Modeling issues have been identified which will require systematic investigation in order to develop the most appropriate strategies for numerical simulation. It appears that numerical simulations will be of ever increasing importance to the study of geothermal processes as the size and complexity of the systems of interest increase. It is anticipated that, in the future, greater emphasis will be placed on the numerical simulation of large-scale, three-dimensional, transient, mixed convection in viscous flows and porous media. Increased computational capabilities, e.g.; massively parallel computers, will allow for the detailed study of specific processes in fractured media, non-Darcy effects in porous media, and non-Newtonian effects. 23 refs., 13 figs., 1 tab.

Hickox, C.E.

1991-01-01T23:59:59.000Z

33

The BaBar Drift Chamber  

E-Print Network (OSTI)

The central drift chamber for the BaBar detector at the PEP-II B-factory at SLAC is a cylindrical chamber with a length of 280 cm and outer radius of 81 cm. It consists of 40 layers of small hexagonal cells arranged in 10 axial and stereo super-layers. In order to minimize multiple scattering, light materials are used for the mechanical structure, and the gas mixture is Helium based. The pulse-height and timing electronics are mounted directly on the chamber rear end-plate. A full length prototype of the BaBar drift chamber has been built. The analysis of cosmic ray events measures the spatial resolution averaged in the cell to be 130 m and the dE/dx resolution to be 6.8%, meeting the performance goals for the BaBar central tracker. The mechanical assembly and stringing of the chamber was completed in December 1997 and the detector will be integrated into BaBar during summer 1998. 1

G. Sciolla

1998-01-01T23:59:59.000Z

34

Global Magma Energy Group | Open Energy Information  

Open Energy Info (EERE)

Global Magma Energy Group Global Magma Energy Group Place Houston, Texas Zip 77056 Sector Geothermal energy Product A geothermal development firm focussed on Asia and backed by Arctas Capital and John Wheble & Associates. Coordinates 29.76045°, -95.369784° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":29.76045,"lon":-95.369784,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

35

Hupmobile cloud chamber parameters  

SciTech Connect

The accompanying table lists the presently selected parameters for the twelve cloud chambers. The chambers are numbered consecutively from 4 through 15 as they are lined up in the bunker. The lowest number is closest to the source. All except the first chamber have some thin metal filters to attenuate the flux and harden the spectrum. Cloud chambers 10, 12, and 14 are shielded by a collimator with about 200 pinholes in it. The flux in these chambers is attenuated by the ratio of the pinhole area to total beam area which is a factor of 50. Various gases and gas pressures are used to obtain suitable track lengths and interaction cross sections. Neon, argon, and krypton are used to obtain photo electrons. Hydrogen is used to obtain Compton electrons.

Hansen, N. E.

1967-09-28T23:59:59.000Z

36

Thermal techniques for characterizing magma body geometries | Open Energy  

Open Energy Info (EERE)

techniques for characterizing magma body geometries techniques for characterizing magma body geometries Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Thermal techniques for characterizing magma body geometries Details Activities (1) Areas (1) Regions (0) Abstract: The surface heat flux distribution resulting from emplaced magma bodies can be used to help characterize the magma source. Closed-form analytical solutions for the conduction heat transfer from various idealized magma geometries (dikes, sills, and spheres) are obtained using either the Schwarz-Christoffel transformation theorem (dikes and sills) or the 'method of images' with superposition (spheres). Comparison of these analytically determined heat flux distributions with field data from active geothermal areas at Yellowstone, Avachinsky volcano, Kilauea Iki,

37

Magma Energy Research Project, FY 1979 annual progress report  

DOE Green Energy (OSTI)

The objective of the Magma Energy Research Project is to define the scientific feasibility of extracting energy from magma bodies. Activities to accomplish the objective are divided into five tasks: resource location and identification; source tapping; magma characterization; materials compatibility; and energy extraction. The program activities of FY 1979 are summarized here according to the individual tasks. Major emphasis of the program in the last year was on field experimentation with the United States Geological Survey in geoscience and technological studies at the Kilauea Iki lava lake. Other major efforts included installation of the magma simulation facility and magma-metal compatibility studies. The Magma Energy Advisory Panel also met during this period. Efforts and results are summarized.

Colp, J.L.

1979-12-01T23:59:59.000Z

38

Selection of promising sites for magma energy experiments  

SciTech Connect

The Long Valley and Coso Hot Springs areas of California have been identified as the most promising sites for conducting a magma energy extraction experiment. These two locations were selected from among the potential sites on the basis of several factors that are critical to the success of the proposed long-term energy extraction experiment. These factors include the likelihood of the existence of shallow magma targets as well as several other drilling, energy extraction and programmatic considerations. As the magma energy extraction program continues, these sites will be analyzed in detail so that one can be selected as the site for the planned magma experiment.

Carson, C.C.

1985-01-01T23:59:59.000Z

39

Solitary Wave Benchmarks in Magma Dynamics  

E-Print Network (OSTI)

We present a model problem for benchmarking codes that investigate magma migration in the Earth's interior. This system retains the essential features of more sophisticated models, yet has the advantage of possessing solitary wave solutions. The existence of such exact solutions to the nonlinear problem make it an excellent benchmark problem for combinations of solver algorithms. In this work, we explore a novel algorithm for computing high quality approximations of the solitary waves and use them to benchmark a semi-Lagrangian Crank-Nicholson scheme for a finite element discretization of the time dependent problem.

Simpson, Gideon

2010-01-01T23:59:59.000Z

40

The Environmental Chamber  

NLE Websites -- All DOE Office Websites (Extended Search)

2 2 The Environmental Chamber Al Hodgson and Richard Allen test methyl chloride exposures using the environmental chamber. On the second floor of an unremarkable building at LBL, researchers are using a room within a room to smoke out indoor air pollutants. The environmental chamber is a stainless-steel-lined room of 540 ft cubed (20 meters cubed) which can be operated in several ways to meet the needs of different research projects, including studies for which a very low background is required. Scientists of the Indoor Environment Program and their collaborators use the chamber as a controlled indoor environment to study the behavior of a variety of indoor pollutants ranging from cigarette smoke to volatile organic compounds (VOCs) from new carpets. At the moment, four projects use the facility. Principal investigator Al

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

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

42

Regulatory, Land Ownership, and Water Availability Factors for a Magma Well: Long Valley Caldera and Coso Hot Springs, California  

DOE Green Energy (OSTI)

The U.S. Department of Energy is currently engaged in a program to demonstrate the engineering feasibility of extracting thermal energy from high-level molten magma bodies. The program is being carried out under the direction of Sandia National Laboratories where a number of individual projects support the overall program. The existing program elements include (1) high-temperature materials compatibility testing; (2) studies of properties of melts of various compositions; and (3) the investigation of the economics of a magma energy extraction system. Another element of the program is being conducted with the cooperation of the U.S. Geological Survey, and involves locating and outlining magma bodies at selected sites using various geophysical techniques. The ultimate goal here will be to define the limits of a magma body as a drilling target. During an earlier phase of the program, more than twenty candidate study sites considered were evaluated based upon: (1) the likelihood of the presence of a shallow magma chamber, (2) the accessibility of the site, and (3) physical and institutional constraints associated with each site with respect to performing long-term experiments. From these early phase activities, the number of candidate sites were eventually narrowed to just 2. The sites currently under consideration are Coso Hot Springs and the Long Valley caldera (Figure 1). This report describes certain attributes of these sites in order to help identify potential problems related to: (1) state and federal regulations pertaining to geothermal development; (2) land ownership; and (3) water resource availability. The information sources used in this study were mainly maps, publications, and informative documents gathered from the California Division of Oil and Gas and the U.S. Department of the Interior. Environmental studies completed for the entire Long Valley caldera study area, and for portions of the Coso Hot Springs study area were also used for reference.

Blackett, Robert

1985-09-01T23:59:59.000Z

43

Photo of Spray Combustion Chamber  

Science Conference Proceedings (OSTI)

NIST Spray Combustion Chamber. NIST, National Institute of Standards and Technology, Material Measurement Laboratory, ...

2013-07-15T23:59:59.000Z

44

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

DOE Green Energy (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

45

Magma energy extraction - Annual Report for FY88  

SciTech Connect

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

Dunn, J.C. (ed.)

1989-08-01T23:59:59.000Z

46

Improved wire chamber  

DOE Patents (OSTI)

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

Atac, M.

1987-05-12T23:59:59.000Z

47

Multi-chamber deposition system  

DOE Patents (OSTI)

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

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

1989-10-17T23:59:59.000Z

48

Multi-chamber deposition system  

DOE Patents (OSTI)

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

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

1989-06-27T23:59:59.000Z

49

Preliminary considerations for extraction of thermal energy from magma  

DOE Green Energy (OSTI)

Simplified mathematical models are developed to describe the extraction of thermal energy from magma based on the concept of a counterflow heat exchanger inserted into the magma body. Analytical solutions are used to investigate influence of the basic variables on electric power production. Calculations confirm that the proper heat exchanger flow path is down the annulus with hot fluid returning to the surface through the central core. The core must be insulated from the annulus to achieve acceptable wellhead temperatures, but this insulation thickness can be quite small. The insulation is effective in maintaining the colder annular flow below expected formation temperatures so that a net heat gain from the formation above a magma body is predicted. The analyses show that optimum flow rates exist that maximize electric power production. These optimum flow rates are functions of the heat transfer coefficients that describe magma energy extraction. 15 refs., 3 figs.

Hickox, C.E.; Dunn, J.C.

1985-01-01T23:59:59.000Z

50

Three chamber negative ion source  

DOE Patents (OSTI)

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

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

1985-01-01T23:59:59.000Z

51

Magma Dynamics at Yucca Mountain, Nevada  

Science Conference Proceedings (OSTI)

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

D. Krier

2005-08-29T23:59:59.000Z

52

CONTINUOUSLY SENSITIVE BUBBLE CHAMBER  

DOE Patents (OSTI)

A radiation detector of the bubble chamber class is described which is continuously sensitive and which does not require the complex pressure cycling equipment characteristic of prior forms of the chamber. The radiation sensitive element is a gas-saturated liquid and means are provided for establishing a thermal gradient across a region of the liquid. The gradient has a temperature range including both the saturation temperature of the liquid and more elevated temperatures. Thus a supersaturated zone is created in which ionizing radiations may give rise to visible gas bubbles indicative of the passage of the radiation through the liquid. Additional means are provided for replenishing the supply of gas-saturated liquid to maintaincontinuous sensitivity.

Good, R.H.

1959-08-18T23:59:59.000Z

53

Argus target chamber  

SciTech Connect

A target chamber for application in the laser fusion program must satisfy some very basic requirements. (1) Provide a vacuum on the order of 10$sup -6$ torr. (2) Support a microscopically small target in a fixed point in space and verify its location within 5 micrometers. (3) Contain an adjustable beam focusing system capable of delivering a number of laser beams onto the target simultaneously, both in time and space. (4) Provide access for diagnostics to evaluate the results of target irradiation. (5) Have flexibility to allow changes in targets, focusing optics and number of beams. The ARGUS laser which is now under construction at LLL will have a target chamber which meets these requirements in a simple economic manner. The chamber and auxiliary equipment are described, with reference to two double beam focusing systems; namely, lenses and ellipsoidal mirrors. Provision is made for future operation with four beams, using ellipsoidal mirrors for two-sided illumination and lens systems for tetragonal and tetrahedral irradiation. (auth)

Rienecker, F. Jr.; Glaros, S.S.; Kobierecki, M.

1975-11-12T23:59:59.000Z

54

Vertical two chamber reaction furnace  

DOE Patents (OSTI)

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

Blaugher, R.D.

1999-03-16T23:59:59.000Z

55

Multi-anode ionization chamber  

DOE Patents (OSTI)

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

Bolotnikov, Aleksey E. (South Setauket, NY); Smith, Graham (Port Jefferson, NY); Mahler, George J. (Rocky Point, NY); Vanier, Peter E. (Setauket, NY)

2010-12-28T23:59:59.000Z

56

Modelling of a magma energy geothermal power plant  

DOE Green Energy (OSTI)

We are currently investigating the engineering feasibility of drilling into an active magma body at a depth of roughly 5 km from the earth's surface, establishing a downhole heat exchange region, and extracting thermal energy from the magma body by circulating fluid through this heat exchange region. In the present paper, we evaluate the overall thermodynamic performance of various conceptual magma energy systems in which energy is added as heat to the fluid within the magma region and is converted to useful work in a power conversion cycle at the surface. Unusually high return temperatures and pressures may be available at the wellhead of such a circulating well. Cycles investigated here are an open Rankine power system in which steam from the magma well is circulated directly through a power conversion cycle and a closed Rankine cycle where the heated fluid from downhole is circulated through an aboveground heat exchanger to heat the cycle fluid. The downhole heat exchange region is established during the drilling process. As drilling proceeds into the magma, a solidified layer forms about the drilling tube due to heat exchange to the fluid. This solidified layer thermally fractures because of large temperature gradients between the cooled inner region and the heated outer region, thereby opening secondary flow paths. Two models of the downhole behavior have been used. In the simplest approach, denoted as the ''infinite area model,'' the water entering the pipe to return to the surface is assumed to be always at the temperature of the magma, independent of mass flow rate and other parameters. The other model is more detatiled and the fractured heat exchange region is modelled as a cylindrical porous layer through which fluid flows vertically. The net power and the performance aspects for the systems are investigated in terms of various parameters, including the characteristics of the downhole heat transfer.

Boehm, R.F.; Berg, D.L.; Jr.; Ortega, A.

1987-01-01T23:59:59.000Z

57

HVAC&R Equipment Environmental Chambers  

Science Conference Proceedings (OSTI)

... with relative humidity controlled within 2 %. Small Appliance and Refrigerator Chamber. This chamber is used to test small ...

2011-11-15T23:59:59.000Z

58

A Multidisciplinary Approach To Detect Active Pathways For Magma Migration  

Open Energy Info (EERE)

Multidisciplinary Approach To Detect Active Pathways For Magma Migration Multidisciplinary Approach To Detect Active Pathways For Magma Migration And Eruption At Mt Etna (Sicily, Italy) Before The 2001 And 2002-2003 Eruptions Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Multidisciplinary Approach To Detect Active Pathways For Magma Migration And Eruption At Mt Etna (Sicily, Italy) Before The 2001 And 2002-2003 Eruptions Details Activities (0) Areas (0) Regions (0) Abstract: Two strong flank eruptions occurred in July-August 2001 and from late October 2002 to late January 2003 at Mt. Etna volcano. The two eruptions mainly involved the upper southern flank of the volcano, a particularly active area during the last 30 years, damaging several tourist facilities and threatening some villages. The composite eruptive activity

59

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

60

Drilling Operations Plan for the Magma Energy Exploratory Well  

DOE Green Energy (OSTI)

This paper is a summary of the proposed drilling plan for the first phase (to 2500 feet depth) of the Magma Energy Exploratory Well. The drilling program comprises four phases, spaced approximately one year apart, which culminate in a large-diameter well to a total depth near 20,000 feet. Included here are descriptions of the well design, predictions of potential drilling problems, a list of restrictions imposed by regulatory agencies, an outline of Sandia's management structure, and an explanation of how the magma energy technology will benefit from this drilling.

Finger, John T.; Livesay, Bill J.; Ash, Don

1989-03-21T23:59:59.000Z

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

Drilling fluid temperatures in a magma - penetrating wellbore  

DOE Green Energy (OSTI)

This paper describes the numerical modeling of the drilling fluid temperatures in a deep well that penetrates a magma body. The basic assumptions for the model are listed, the importance of the fluid temperature is considered, and the effect of changing the model parameters is assessed. The stratigraphy and formation temperature profile assumed for this hypothetical well are similar to Long Valley, CA, where a relatively shallow magma body is believed to exist. A major result of this modeling is demonstration of the benefit of insulated drillpipe.

Finger, J.T.

1986-01-01T23:59:59.000Z

62

PWR AXIAL BURNUP PROFILE ANALYSIS  

Science Conference Proceedings (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

63

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

DOE Green Energy (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

64

A MODIFIED LUNDEGARDH SPRAY CHAMBER  

SciTech Connect

Operation of an apparatus for analysis of solutions by the Lundegardh flame technique was greatiy facilituted by the modification of a spray chamber. Samples can be introduced and removed from the modified spray chamber without extinguishing the flame or dismantling the assembly. (auth)

Palin, P.C.

1951-04-01T23:59:59.000Z

65

LRL 25-inch Bubble Chamber  

DOE R&D Accomplishments (OSTI)

The recently completed 25-inch hydrogen bubble chamber combines excellent picture quality with a fast operating cycle. The chamber has a unique optical system and is designed to take several pictures each Bevatron pulse, in conjunction with the Bevatron rapid beam ejection system.

Alvarez, L. W.; Gow, J. D.; Barrera, F.; Eckman, G.; Shand, J.; Watt, R.; Norgren, D.; Hernandez, H. P.

1964-07-08T23:59:59.000Z

66

National Ignition Facility Target Chamber  

DOE Green Energy (OSTI)

On June 11, 1999 the Department of Energy dedicated the single largest piece of the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) in Livermore, California. The ten (10) meter diameter aluminum target high vacuum chamber will serve as the working end of the largest laser in the world. The output of 192 laser beams will converge at the precise center of the chamber. The laser beams will enter the chamber in two by two arrays to illuminate 10 millimeter long gold cylinders called hohlraums enclosing 2 millimeter capsule containing deuterium, tritium and isotopes of hydrogen. The two isotopes will fuse, thereby creating temperatures and pressures resembling those found only inside stars and in detonated nuclear weapons, but on a minute scale. The NIF Project will serve as an essential facility to insure safety and reliability of our nation's nuclear arsenal as well as demonstrating inertial fusion's contribution to creating electrical power. The paper will discuss the requirements that had to be addressed during the design, fabrication and testing of the target chamber. A team from Sandia National Laboratories (SNL) and LLNL with input from industry performed the configuration and basic design of the target chamber. The method of fabrication and construction of the aluminum target chamber was devised by Pitt-Des Moines, Inc. (PDM). PDM also participated in the design of the chamber in areas such as the Target Chamber Realignment and Adjustment System, which would allow realignment of the sphere laser beams in the event of earth settlement or movement from a seismic event. During the fabrication of the target chamber the sphericity tolerances had to be addressed for the individual plates. Procedures were developed for forming, edge preparation and welding of individual plates. Construction plans were developed to allow the field construction of the target chamber to occur parallel to other NIF construction activities. This was necessary to achieve the overall schedule. Plans had to be developed for the precise location and alignment of laser beam ports. Upon completion of the fabrication of the aluminum target chamber in a temporary structure the 130 ton sphere was moved from the temporary construction enclosure to its final location in the target building. Prior to the installation of a concrete shield and after completion of the welding of the chamber penetrations vacuum leak checking was performed to insure the vacuum integrity of target chamber. The entire spherical chamber external surface supports a 40 cm thick reinforced concrete shield after installation in the target building. The final task is a total survey of the laser ports and the contour machining of spacer plates so that laser devices attached to these ports meet the alignment criteria.

Wavrik, R W; Cox, J R; Fleming, P J

2000-10-05T23:59:59.000Z

67

Save Energy with Axial Fans  

E-Print Network (OSTI)

There are several ways to save energy in wet cooling towers and air cooled heat exchangers using axial fans. This paper will discuss ways to improve fan system efficiency in wet and dry towers both during the design phase and after installation by specifying energy efficient equipment. Variable pitch fan versus fixed pitch fan operation is discussed in terms of energy savings and means of control. The areas of interest to wet cooling tower users would be the influence on fan diameter and operating point on horsepower, how and when are velocity recovery stacks effective, the effect of varying fan speed to improve efficiency, and tip clearance effects. The areas of interest to dry tower (air cooled heat exchanger) users would be the effect of inlet losses, approach velocity losses, and losses due to air recirculation.

Monroe, R. C.

1981-01-01T23:59:59.000Z

68

Orientation of stationary axial collectors  

SciTech Connect

Attention is drawn to the fact that stationary solar collectors with axial symmetry have a third degree of freedom which must be considered, in addition to their azimuth and tilt angles, if their orientation is to be optimized on an annual or seasonal basis. The authors set up the equations needed to describe collector orientation in terms of all angles, including this extra degree of freedom which they refer to as skewness. Examples of the use of these equations are then given, both for northern and southern latitudes, which illustrate the manner in which skewness may be taken into consideration and highlight the importance of doing this. For the sake of simplicity the illustrative examples treat only the direct beam component of the total insolation intercepted by the collector.

Faiman, D.; Mills, D.R. (Sydney Univ., New South Wales (Australia))

1992-10-01T23:59:59.000Z

69

Origin of axial current in scyllac  

SciTech Connect

The origin of the axial current observed in Scyllac (a high beta stellarator experiment) is discussed. A shaped coil and/or helical winding produce rotational transform which links magnetic lines of force to the plasma column and the axial current is induced electromagnetically. This phenomenon is inherent in a pulsed high-beta stellarator. The rotational transform produced by the induced axial current is much smaller than that associated with the l = 1, 0 equilibrium fields. The effect of the axial current on the equilibrium and stability of the plasma column is thus small. It is also shown that the magnetic field shear near a plasma surface is very strong. (auth)

Sugisaki, K.

1975-12-01T23:59:59.000Z

70

Magma Energy Research Project. Project summary, July 1, 1974--June 30, 1975  

DOE Green Energy (OSTI)

The objective of the Magma Energy Research Project now under way at Sandia Laboratories is to investigate the feasibility of extracting energy directly from deeply buried circulating magma sources. Project plans describe a concept whereby a fully closed heat exchanger system is inserted directly into such a magma source to allow the heat energy to be brought to the surface with minimal environmental impact. A summary of previous efforts is given. The achievements and future plans for source location and definition, source tapping, magma characterization, magma materials compatibilities studies, and energy extraction studies are outlined. (LBS)

Colp, J.L.; Davis, M.J.; Graeber, E.J.; Hardee, H.C.

1976-03-01T23:59:59.000Z

71

Hydrodynamic design of axial hydraulic turbines  

Science Conference Proceedings (OSTI)

This paper presents a complete methodology of the hydrodynamic design for the runner of axial hydraulic turbines (Kaplan) using the finite element method. The procedure starts with the parametric design of the meridian channel. Next, the stream traces ... Keywords: QTurbo3D, axial hydraulic turbines, design, meridian channel, runner blade

Daniel Balint; Viorel Cmpian

2011-04-01T23:59:59.000Z

72

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.

Carlsten, Bruce E. (Los Alamos, NM)

1997-01-01T23:59:59.000Z

73

Humidity effects in ionization chambers  

SciTech Connect

Capacitance variations due to humidity alterations have been suggested as the cause of ionization chamber current variations. The validity of the arguments is seriously questioned on several points. (auth)

Bengtsson, L.G.

1973-01-01T23:59:59.000Z

74

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

75

A University of Alabama Axial-Gap Electric Motor Developmenty  

E-Print Network (OSTI)

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

Carver, Jeffrey C.

76

Search for shallow magma accumulations at Augustine Volcano  

DOE Green Energy (OSTI)

A search was made for shallow magma accumulations beneath Augustine Volcano using primarily three geophysical techniques: (1) temperature and heat flow measurements, (2) active and passive seismic refraction, and (3) three-dimensional modeling of aeromagnetic data. With these studies it was hoped to gain insight into the interval structure of Augustine Volcano, to delineate, if possible, the size and shape of near surface magma bodies and to assess the potential of the volcano as a natural laboratory for hot rock and magma geothermal energy research. Augustine was chosen because it is a very young and very active volcano with several historic eruptions in 1812, 1883, 1935, 1964/64. One of the main targets for the geophysical studies was a summit lava dome of about 0.05 km/sup 3/ volume, extruded in 1963/64 and suspected to still contain considerable residual heat, perhaps be still partially molten years after its intrusion. Five months after the field work in 1975 this dome was exploded in January 1976. One month later, a hot (about 650 to 800/sup 0/C) viscous dome was intruded into the January summit crater.

Kienle, J.; Lalla, D.J.; Pearson, C.F.; Barrett, S.A.

1979-05-01T23:59:59.000Z

77

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

SciTech Connect

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

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

2010-05-21T23:59:59.000Z

78

Plasma chemistry in wire chambers  

SciTech Connect

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

Wise, J.

1990-05-01T23:59:59.000Z

79

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

80

Axial grading of inert matrix fuels  

Science Conference Proceedings (OSTI)

Burning actinides in an inert matrix fuel to 750 MWd/kg IHM results in a significant reduction in transuranic isotopes. However, achieving this level of burnup in a standard light water reactor would require residence times that are twice that of uranium dioxide fuels. The reactivity of an inert matrix assembly at the end of life is less than 1/3 of its beginning of life reactivity leading to undesirable radial and axial power peaking in the reactor core. Here we show that axial grading of the inert matrix fuel rods can reduce peaking significantly. Monte Carlo simulations are used to model the assembly level power distributions in both ungraded and graded fuel rods. The results show that an axial grading of uranium dioxide and inert matrix fuels with erbium can reduces power peaking by more than 50% in the axial direction. The reduction in power peaking enables the core to operate at significantly higher power. (authors)

Recktenwald, G. D.; Deinert, M. R. [Dept. of Mechanical Engineering, Univ. of Texas, Austin, TX (United States)

2012-07-01T23:59:59.000Z

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

Preliminary analysis of two aspects of magma-powered electric-generation plants  

DOE Green Energy (OSTI)

Two aspects critical to the development of magma electric generation plants using closed heat exchanger systems are addressed. The heat transfer between the cold fluid in the downcomer and the hot fluid in the upcomer is analyzed using an NTU-effectiveness technique. The results indicate the hot fluid must be thermally insulated from the colder fluid in order to yield a useful temperature difference at the surface. A preliminary system analysis is conducted to determine the well cost requirements of an economically competitive magma electric plant. There is no economic incentive to make the magma tap wellbore larger than conventional deep gas wells. The cost competitiveness of a magma/electric plant is influenced by the depth to the magma, the convective heat flux of the magma, and the expected life of each well.

Hoover, E.R.

1980-09-01T23:59:59.000Z

82

MAGMA DYNAMICS IN GABBROIC SILLS, KAROO, SOUTH AFRICA: CONSTRAINTS FROM MAGNETIC INVESTIGATIONS AND MAGNETIC FABRICS.  

E-Print Network (OSTI)

??Gabbroic rocks in sills commonly display well organized magnetic fabrics that are generally attributed to magma flow. Yet in a number of cases, magnetic fabrics (more)

Marsh, Michael C.

2010-01-01T23:59:59.000Z

83

Workshop on magma/hydrothermal drilling and instrumentation  

DOE Green Energy (OSTI)

The discussions, conclusions, and recommendations of the Magma/Hydrothermal Drilling and Instrumentation Workshop, Albuquerque, NM, May 31--June 2, 1978 are summarized. Three working groups were organized as follows: Drilling Location and Environment, Drilling and Completion Technology, and Logging and Instrumentation Technology. The first group discussed potential drilling sites and the environment that could be expected in drilling to magma depth at each site. Sites suggested for early detailed evaluation as candidate drilling sites were The Geysers-Clear Lake, CA, Kilauea, HI, Long Valley-Mono Craters, CA, and Yellowstone, WY. Magma at these sites is expected to range from 3 to 10 km deep with temperatures of 800 to 1100{sup 0}C. Detailed discussions of the characteristics of each site are given. In addition, a list of geophysical measurements desired for the hole is presented. The Drilling and Completion Group discussed limitations on current rotary drilling technology as a function of depth and temperature. The group concluded that present drilling systems can be routinely used to temperatures of 200{sup 0}C and depths to 10 km; drilling to 350{sup 0}C can be accomplished with modifications of present techniques, drilling at temperatures from 350{sup 0}C to 1100{sup 0}C will require the development of new drilling techniques. A summary of the limiting factors in drilling systems is presented, and recommendations for a program directed at correcting these limitations is described. The third group discussed requirements for instrumentation and established priorities for the development of the required instruments. Of highest priority for development were high resolution temperature tools, sampling techniques (core, formation fluids), chemical probes, and communications techniques. A description of instrumentation requirements for the postulated hole is given, and the tasks necessary to develop the required devices are delineated.

Varnado, S.G.; Colp, J.L. (eds.)

1978-07-01T23:59:59.000Z

84

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

85

Animated axial surface mapping: The multimedia companion  

SciTech Connect

This newly expanded version of AAPG`s first DataShare Disk brings to life the concepts and applications of a new method of structural trend analysis. Through the dynamic use of color, sound, animation, and humor, this multimedia companion to the May 1994 article on Axial Surface Mapping introduces the reader (or viewer) to the concepts of rigid-block translation, fault-bend folding, and axial surface mapping. Animated models of growing fault-bend folds allow the viewer to see in four dimensions. The axial surface map shows the horizontal plane; the folding lines show depth planes; and the animations show the structure and its two-dimensional map changing with time and increasing slip. The animations create theoretical map patterns under varying, but controlled conditions that can be compared to axial surface maps from real data. The model patterns are then used to interpret seismic data and axial surface maps from a producing gas field in offshore California and from an exploration play in Pennsylvania.

Hook, S.C.; Shaw, J.H. [Texaco EPTD, Houston, TX (United States); Suppe, J. [Princeton Univ., Princeton, NJ (United States)

1995-09-01T23:59:59.000Z

86

Signatures of confinement in axial gauge QCD  

SciTech Connect

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

Lenz, F. [Institute for Theoretical Physics, University of Erlangen-Nuernberg, Staudtstrasse 7, 91058 Erlangen (Germany)]|[Center for Theoretical Physics, Laboratory for Nuclear Science, MIT, Cambridge, Massachusetts 02139 (United States); Moniz, E.J. [Center for Theoretical Physics, Laboratory for Nuclear Science, MIT, Cambridge, Massachusetts 02139 (United States)]|[Institute for Theoretical Physics, University of Erlangen-Nuernberg, Staudtstrasse 7, 91058 Erlangen (Germany); Thies, M. [Institute for Theoretical Physics, University of Erlangen-Nuernberg, Staudtstrasse 7, 91058 Erlangen (Germany)

1995-09-01T23:59:59.000Z

87

AN IONIZATION CHAMBER LAUNDRY MONITOR  

SciTech Connect

The determination of the amount of contamination remaining on a garment after it has been washed is an important part of hot laundry operations. In the past garments were monitored by measuring the contamination concentrated in the crotch with a GM tube probe. This type of spot check does not detect any isolated hot spots on other pants of the garment. To monitor the entire garment with a GM tube instrument is excessively time consuming for a large number of garments. To overcome these difficulties a sensitive, large-volume ionization chamber was constructed. It is rectangular in shape, 5 ft high by 2 1/2 ft wide by 4 in. deep. The center electrode is of a grid type and is mounted halfway between the front window and the back of the chamber. In a 0.5-mr/hr field, 180 v is sufficient to saturate toe chamber. In order to insure beta sensitivity, the front window has an equivalent thickness of approximately 7 mg/cm/sup 2/. The measuring device is a line-operated electrometer circuit equipped with an alarm that may be set at the rejection limit for the type of garment being monitored. A fullscale deflection on the most sensitive range is given by 2 to 3 mu C of liquid mixed fission products deposited on a garment. Since the chamber monitors the entire garment, the results are independent of the location of the contarnination. In practice, garments may be monitored at the rate of 7 per min, while only 3 per min may be completely checked with a GM tube probs. Field tests indicate that this instrument is stable and trouble free. Background causes a meter deflection of about 20 divisions, which is low enough to give reliable accuracy for monitoring garments. (auth)

Chester, J.D.; Handloser, J.S.

1958-06-01T23:59:59.000Z

88

Chamber Comments on Cybersecurity Green Paper Final  

Science Conference Proceedings (OSTI)

... Using security disclosure as an incentive, its authors ... The Chamber noted that incentives would prove more productive than regulation. ...

2011-08-19T23:59:59.000Z

89

Noise Analysis of Statham Temperature Chamber  

SciTech Connect

A procedure is described to subdue the noise made by the LN2 control valve on a Statham Temperature Chamber.

Mielke, R. L.

1973-01-15T23:59:59.000Z

90

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

91

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

92

Program to investigate the engineering feasibility of extracting energy from shallow magma bodies  

SciTech Connect

A new program, sponsored by the Department of Energy's Geothermal and Hydropower Technologies Division, has begun to investigate the engineering feasibility of extracting energy from shallow magma bodies. This program follows a previous investigation of the scientific feasibility of using magma and differs from it in focus. The current program is directed toward determining whether magma energy can be extracted economically. In the first year of the program, the three most promising sites for a long term experiment will be characterized; the research and development tasks that will be required will be identified; and a program plan outlining the entire feasibility study will be compiled.

Carson, C.C.; Allen, A.D.

1984-01-01T23:59:59.000Z

93

Review of Axial Burnup Distribution Considerations for Burnup Credit Calculations  

SciTech Connect

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

94

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

95

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

DOE Green Energy (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

96

Axial Compressor Performance Maintenance Guide Update  

Science Conference Proceedings (OSTI)

To deal with volatile fuel prices and growing pressures to limit greenhouse gas (GHG) emissions, combustion turbine (CT) operators are striving for maximum fuel efficiency. The axial compressor is a leading cause of short term and long term CT efficiency losses due to fouling, corrosion, and erosion. This report reviews the technology being advanced for compressor maintenance to achieve improved compressor and the CT efficiencies.

2005-02-21T23:59:59.000Z

97

Cyclotron axial ion-beam-buncher system  

DOE Patents (OSTI)

Adiabatic ion bunching is achieved in a cyclotron axial ion injection system through the incorporation of a radio frequency quadrupole system, which receives ions from an external ion source via an accelerate-decelerate system and a focusing einzel lens system, and which adiabatically bunches and then injects the ions into the median plane of a cyclotron via an electrostatic quadrupole system and an inflection mirror.

Hamm, R.W.; Swenson, D.A.; Wangler, T.P.

1982-02-11T23:59:59.000Z

98

Strategic Capacity Axial-Compressor Maintenance Program (SCAMP) Version 2  

Science Conference Proceedings (OSTI)

The Strategic Capacity Axial-Compressor Maintenance Program (SCAMP) spreadsheet provides combustion turbine operators with a low-cost, easy-to-install, easy-to-use program for monitoring combustion turbine (CT) axial compressor performance. Utilities can use it to diagnose the condition of axial compressors and to determine the benefits of maintenance actions such as an off-line compressor wash.

2000-11-29T23:59:59.000Z

99

Georges Charpak, Particle Detectors, and Multiwire Chambers  

NLE Websites -- All DOE Office Websites (Extended Search)

Georges Charpak, Particle Detectors, and Multiwire Chambers Georges Charpak, Particle Detectors, and Multiwire Chambers Resources with Additional Information · Patents Georges Charpak Courtesy of CERN Nobel laureate Georges Charpak [was] a pioneer in the art and science of particle detection ... . [He] developed a host of particle detectors used throughout experimental particle physics. In 1968, he invented and developed the first multiwire proportional chamber, for which he won the [Physics] Nobel Prize in 1992 ... . The multiwire chamber differed from earlier detectors in the speed with which it could record particle tracks from a collision-millions per second, rather than one or two per second for bubble chambers. The speed of the multiwire chamber and its successor technologies, along with their extraordinary precision, led to a revolution in particle physics ... . The technology that Charpak pioneered also finds applications in medicine and industry.

100

Fluidized wall for protecting fusion chamber walls  

DOE Patents (OSTI)

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

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


101

Type A: Magma-heated, Dry Steam Resource | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Type A: Magma-heated, Dry Steam Resource Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Type A: Magma-heated, Dry Steam Resource Dictionary.png Type A: Magma-heated, Dry Steam Resource: No definition has been provided for this term. Add a Definition Brophy Occurrence Models This classification scheme was developed by Brophy, as reported in Updating the Classification of Geothermal Resources.[1] Type A: Magma-heated, Dry Steam Resource Type B: Andesitic Volcanic Resource Type C: Caldera Resource Type D: Sedimentary-hosted, Volcanic-related Resource Type E: Extensional Tectonic, Fault-Controlled Resource

102

Insitu Oxygen Conduction Into Internal Combustion Chamber  

Insitu Oxygen Conduction Into Internal Combustion Chamber Note: The technology described above is an early stage opportunity. Licensing rights to this ...

103

The Mark II Vertex Drift Chamber  

SciTech Connect

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

104

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

DOE Green Energy (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

105

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

E-Print Network (OSTI)

IFE Chamber Technology Testing Program In NIF and Chamber Development Test Plan Mohamed A. Abdou chamber technology testing program in NIF involoving: criteria for evaluation prior to NIF testing were addressed in this paper. In order to maximize the benefits of testing program

Abdou, Mohamed

106

Axial Tomography from Digitized Real Time Radiography  

DOE R&D Accomplishments (OSTI)

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

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

1985-01-18T23:59:59.000Z

107

Axial tomography from digitized real time radiography  

SciTech Connect

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

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

1985-01-18T23:59:59.000Z

108

Ionization-chamber smoke detector system  

DOE Patents (OSTI)

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

Roe, Robert F. (Jackson, OH)

1976-10-19T23:59:59.000Z

109

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

DOE Patents (OSTI)

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

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

1964-01-21T23:59:59.000Z

110

Commissioning of SLAC SLD 45-Degree Chambers  

E-Print Network (OSTI)

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

V. O. Eschenburg

2002-07-30T23:59:59.000Z

111

Secondary air interaction with main flow in axial turbines.  

E-Print Network (OSTI)

??Secondary air, known as purge air, is injected through seals in the hub and shroud of axial turbines to prevent hot gas ingestion into the (more)

Zlatinov, Metodi B. (Metodi Blagoev)

2011-01-01T23:59:59.000Z

112

Axial charges of the nucleon and N* resonances  

E-Print Network (OSTI)

The axial charges of the nucleon and the well-established N* resonances are studied within a consistent framework. For the first time the axial charges of the N* resonances are produced for the relativistic constituent quark model. The axial charge of the nucleon is predicted close to experiment, and the ones of N*(1535) and N*(1650), the only cases where such a comparison is possible, agree well with results from quantum chromodynamics on the lattice that have recently become available. The relevance of the magnitudes of the N* axial charges for the low-energy behavior of quantum chromodynamics is discussed.

Ki-Seok Choi; W. Plessas; R. F. Wagenbrunn

2009-08-27T23:59:59.000Z

113

Optimization of Active Noise Control for Small Axial Cooling Fans.  

E-Print Network (OSTI)

??Previous work has shown that active noise control is a feasible solution to attenuate tonal noise radiated by small axial cooling fans, such as those (more)

Monson, Brian B 1979-

2006-01-01T23:59:59.000Z

114

Absorption of axially asymmetric waves in inhomogeneous plasma  

SciTech Connect

It is shown that the periphery of an inhomogeneous plasma is trasparent to axially asymmetric waves with certain azimuthal indices.(AIP)

Dnestrovskii, Y.N.; Kostomarov, D.P.; Pereverzev, G.V.

1976-08-01T23:59:59.000Z

115

A TIME PROJECTION CHAMBER DIGITIZER TEST SYSTEM USING A MICROCOMPUTER  

E-Print Network (OSTI)

R. Nygren, "The Time Projection Chamber", Physics Today, pp.out System for the Time Projection Chamber", IEEE Trans.on Nuclear Science A TIME PROJECTION CHAMBER DIGITIZER TEST

Nunnally, Curtis

2013-01-01T23:59:59.000Z

116

Volatile contents in subduction-related basaltic magmas from Central Mexico: considerations on mantle enrichment processes and low pressure magma degassing during basaltic eruptions  

E-Print Network (OSTI)

Melt inclusions in olivine phenocrysts from primitive lavas from five different volcanoes in the Sierra Chichinautzin (Central Mexico) were analyzed by infrared spectroscopy and electron microprobe to determine their major element chemistry and their H?O and CO? concentrations. The compositions of the inclusions range from basalt to andesite and include both alkaline and calc-alkaline varieties. Most inclusions have low H?O concentrations (average values 0.4[]0.2 wt.% H?O for Xitle, 0.6[]0.5 wt.% for Tuxtepec, 0.6[]0.3 wt.% for Ixcatepec, 0.8[]0.5 wt.% for Las Tetillas, 1.0[]0.3 wt.% for Jumiltepec) and no measurable CO?. The lack of CO?, which has strongly pressure-dependent solubility in silicate melts, and the low and variable H?O contents indicate that low pressure degassing is a widespread phenomenon during basaltic cinder cone eruptions. One model is presented to explain the extensive low pressure degassing in a well studied volcano (Xitle). The model explains the formation of an initial tephra cone and its temporal growth by explosive events followed by a switch in eruptive style to effusive. The model is based on the fact that cinder cones are highly porous, which allows efficient degassing of reticulating, low viscosity basaltic magma. The presence of alkaline and calc-alkaline primitive lavas throughout the volcanic field indicates heterogeneities in source region compositions. Rare melt inclusions in the primitive lavas contain measurable CO? and were trapped at relatively high pressures (~1 to 3 kb). These inclusions constrain the primary H?O contents of the magmas before low pressure degassing. The results clearly show that the calc-alkaline magmas contain higher H?O (~2 to 4 wt%) than the alkaline (~1 wt.%). Calculations of a hypothetical mantle source and comparison with EMORB and NMORB mantle sources shows that these volcanics were formed by two different processes: (1) partial melting caused by fluxing of the mantle wedge with a water-rich component from the subjected slab (calc-alkaline magmas) and (2) partial melting of the mantle wedge by upwelling-induced decompression (alkaline magmas). These two processes can be considered as end-members in arc magma genesis.

Cervantes, Pablo

1999-01-01T23:59:59.000Z

117

Very high intensity reaction chamber design  

SciTech Connect

The problem of achieving very high intensity irradiation by light in minimal regions was studied. Three types of irradiation chamber are suggested: the common laser-reaction chamber, the folded concentric or near-concentric resonator, and the asymmetric confocal resonator. In all designs the ratio of high-intensity illuminated volume to other volume is highly dependent (to the $sup 3$/$sub 2$ power) on the power and fluence tolerances of optical elements, primarily mirrors. Optimization of energy coupling is discussed for the common cavity. For the concentric cavities, optimization for both coherent and incoherent beams is treated. Formulae and numerical examples give the size of chambers, aspect ratios, maximum pass number, image sizes, fluences, and the like. Similarly for the asymmetric confocal chamber, formulae and numerical examples for fluences, dimensions, losses, and totally contained pass numbers are given. (auth)

Devaney, J.J.

1975-09-01T23:59:59.000Z

118

Searches for charmed particles using bubble chambers  

SciTech Connect

Searches for charm particle production using bubble chambers are summarized. These searches depend on the detection of neutral strange particles. Upper limits are given for the different charmed mass regions and methods of search. (auth)

Harris, R.

1975-10-01T23:59:59.000Z

119

Atlas chamber, power flow channel, and diagnostic interface design  

DOE Green Energy (OSTI)

The Atlas pulsed-power machine, presently being designed at Los Alamos, will deliver a pulse of {approximately} 45 MA, in 4--5 {micro}sec, with energies of up to 6 MJ (from a bank of 36 MJ maximum) to a load assembly, located in vacuum. Design considerations for the vacuum vessel, power flow channel from the vessel inward, are presented. In contrast to Sandia`s PBFA II-Z, where 20 MA currents and 2--2.5 MJ of energy are delivered to ({approximately} 15 mg) loads in {approximately} 100 nsec, the Atlas structures will have to be designed for longer timescales and higher energies to drive heavy lines ({approximately} 70 g). Design issues for the chamber include materials stresses, formation of (and protection from) debris and molten jets, impulse loading, and survivability and ease of replacement of internal structures. For the power flow channel designs, issues are minimizing inductance, preventing movement of conductors during and after firing, damage mitigation, reducing the cost of materials and installation, and electrical insulation. A key issue for damage mitigation is the radius within which total destruction of material objects occurs. Choices of vessel size, insulator materials, cost and ease of manufacturing, and mechanical stability issues are presently in the conceptual design phase. Typical access requirements for diagnostics (including radial and axial X-ray backlighting, flux loops, spectroscopy, interferometry, bolometry, etc.) are provided for in the design.

Wurden, G.A.; Davis, H.A.; Taylor, A.; Bowman, D.; Ballard, E.; Ney, S.; Scudder, D.; Trainor, J.

1997-09-01T23:59:59.000Z

120

40Ar-39Ar Geochronology Of Magmatic Activity, Magma Flux And Hazards At  

Open Energy Info (EERE)

Ar-39Ar Geochronology Of Magmatic Activity, Magma Flux And Hazards At Ar-39Ar Geochronology Of Magmatic Activity, Magma Flux And Hazards At Ruapehu Volcano, Taupo Volcanic Zone, New Zealand Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: 40Ar-39Ar Geochronology Of Magmatic Activity, Magma Flux And Hazards At Ruapehu Volcano, Taupo Volcanic Zone, New Zealand Details Activities (0) Areas (0) Regions (0) Abstract: We have determined precise eruption ages for andesites from Ruapehu volcano in the Tongariro Volcanic Centre of the Taupo Volcanic Zone (TVZ) using 40Ar/39Ar furnace step-heating of separated groundmass concentrates. The plateau ages indicate several eruptive pulses near 200, 134, 45, 22 and <15 ka and, based on our and previous field mapping confirm the lavas of the Te Herenga Formation as the oldest exposed part of the

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

Automated Soil Gas Monitoring Chamber - Oak Ridge National ...  

Automated Soil Gas Monitoring Chamber ... A chamber for trapping soil gases as they evolve from the soil without disturbance to the soil and to the natural

122

High Power Co-Axial SRF Coupler  

SciTech Connect

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

123

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

SciTech Connect

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

124

Chemical evolution of a high-level magma system: the Black Mountain volcanic center, southern Nevada  

DOE Green Energy (OSTI)

A comprehensive study of stratigraphically controlled samples of both lavas and ash-flow tuffs from the Black Mountain volcanic center enables us to evaluate magmatic processes. The results of this study are used to: (1) determine how this high-level magma system developed; (2) compare this system with other similar systems; and (3) correlate ash-flow sheets using their chemical characteristics.

Vogel, T.A.; Noble, D.C.; Younker, L.W.

1983-09-01T23:59:59.000Z

125

Magma flow inferred from AMS fabrics in a layered mafic sill, Insizwa, South Africa  

E-Print Network (OSTI)

Basalt (CFB) province in Southern Africa. This Lower Jurassic CFB prov- ince displays exceptionally good exposures, along a several kilometer-thick section, from the top Drakens- berg Formation basalt lava flows shallow down away from the feeder. (A) Pipe feeder where magma supply originates from a single vertical

Ferré, Eric

126

Distribution of magma beneath the Toba caldera complex, north Sumatra, Indonesia, constrained by  

E-Print Network (OSTI)

Distribution of magma beneath the Toba caldera complex, north Sumatra, Indonesia, constrained and Geophysical Agency, Jakarta, Indonesia R. McCaffrey, D. A. Wark, and S. W. Roecker Department of Earth@rpi.edu) Fauzi and G. Ibrahim Meteorological and Geophysical Agency, Jakarta, Indonesia (fauzi@bmg.go.id) Sukhyar

McCaffrey, Robert

127

Variations in volatiles in magma bodies based on studies of melt inclusions  

DOE Green Energy (OSTI)

Knowledge of volatile concentrations in magmas are important in the prediction of explosive volcanism, and contribute to the understanding of the carbon dioxide budget of the atmosphere. Some important variables that are controlled by volatiles are: crystallization temperature of phases, composition of liquids minimum, and viscosity. Volatiles are also catalysts for reactions.

Vogel, T.A. (Michigan State Univ., East Lansing, MI (USA). Dept. of Geological Sciences)

1989-06-15T23:59:59.000Z

128

Conservative axial burnup distributions for actinide-only burnup credit  

SciTech Connect

Unlike the fresh fuel approach, which assumes the initial isotopic compositions for criticality analyses, any burnup credit methodology must address the proper treatment of axial burnup distributions. A straightforward way of treating a given axial burnup distribution is to segment the fuel assembly into multiple meshes and to model each burnup mesh with the corresponding isotopic compositions. Although this approach represents a significant increase in modeling efforts compared to the uniform average burnup approach, it can adequately determine the reactivity effect of the axial burnup distribution. A major consideration is what axial burnup distributions are appropriate for use in light of many possible distributions depending on core operating conditions and histories. This paper summarizes criticality analyses performed to determine conservative axial burnup distributions. The conservative axial burnup distributions presented in this paper are included in the Topical Report on Actinide-Only Burnup Credit for Pressurized Water Reactor Spent Nuclear Fuel Packages, Revision 1 submitted in May 1997 by the US Department of Energy (DOE) to the US Nuclear Regulatory Commission (NRC). When approved by NRC, the conservative axial burnup distributions may be used to model PWR spent nuclear fuel for the purpose of gaining actinide only burnup credit.

Kang, C.; Lancaster, D.

1997-11-01T23:59:59.000Z

129

Deep Borehole Measurements for Characterizing the Magma/Hydrothermal System at Long Valley Caldera, CA  

DOE Green Energy (OSTI)

The Magma Energy Program of the Geothermal Technology Division is scheduled to begin drilling a deep (6 km) exploration well in Long Valley Caldera, California in 1989. The drilling site is near the center of the caldera which is associated with numerous shallow (5-7 km) geophysical anomalies. This deep well will present an unparalleled opportunity to test and validate geophysical techniques for locating magma as well as a test of the theory that magma is still present at drillable depths within the central portion of the caldera. If, indeed, drilling indicates magma, the geothermal community will then be afforded the unique possibility of examining the coupling between magmatic and hydrothermal regimes in a major volcanic system. Goals of planned seismic experiments that involve the well include the investigation of local crustal structure down to depths of 10 km as well as the determination of mechanisms for local seismicity and deformation. Borehole electrical and electromagnetic surveys will increase the volume and depth of rock investigated by the well through consideration of the conductive structure of the hydrothermal and underlying regimes. Currently active processes involving magma injection will be studied through observation of changes in pore pressure and strain. Measurements of in situ stress from recovered cores and hydraulic fracture tests will be used in conjunction with uplift data to determine those models for magmatic injection and inflation that are most applicable. Finally, studies of the thermal regime will be directed toward elucidating the coupling between the magmatic source region and the more shallow hydrothermal system in the caldera fill. To achieve this will require careful logging of borehole fluid temperature and chemistry. In addition, studies of rock/fluid interactions through core and fluid samples will allow physical characterization of the transition zone between hydrothermal and magmatic regimes.

Carrrigan, Charles R.

1989-03-21T23:59:59.000Z

130

Fluorescence Axial Localization with Nanometer Accuracy and Precision  

SciTech Connect

We describe a new technique, standing wave axial nanometry (SWAN), to image the axial location of a single nanoscale fluorescent object with sub-nanometer accuracy and 3.7 nm precision. A standing wave, generated by positioning an atomic force microscope tip over a focused laser beam, is used to excite fluorescence; axial position is determined from the phase of the emission intensity. We use SWAN to measure the orientation of single DNA molecules of different lengths, grafted on surfaces with different functionalities.

Li, Hui; Yen, Chi-Fu; Sivasankar, Sanjeevi

2012-06-15T23:59:59.000Z

131

Amplifier Design for Proportional Ionization Chambers  

SciTech Connect

This paper presents the requirements of a nuclear amplifier of short resolving time, designed to accept pulses of widely varying amplitudes. Data are given which show that a proportional ionization chamber loaded with a 1,000-ohm resistor develops pulses of 0.5 microsecond duration and several volts amplitude. Results indicate that seven basic requirements are imposed on the amplifier when counting soft beta and gamma radiation in the presence of alpha particles, without absorbers. It should, (1) have a fast recovery time, (2) have a relatively good low frequency response, (3) accept pulses of widely varying heights without developing spurious pulsed, (4) have a limiting output stage, (5) preserve the inherently short rise time of the chamber, (6) minimize pulse integration, and (7) have sufficient gain to detect the weak pulses well below the chamber voltage at which continuous discharge takes place. The results obtained with an amplifier which meets these requirements is described. A formula is derived which indicates that redesign of the proportional ionization chamber might eliminate the need for an amplifier. This may be possible if the radioactive particles are collimated parallel to the collecting electrode.

Baker, W. H.

1950-08-24T23:59:59.000Z

132

Miniature reaction chamber and devices incorporating same  

DOE Patents (OSTI)

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

Mathies, Richard A. (Moraga, CA); Woolley, Adam T. (Albany, CA)

2000-10-17T23:59:59.000Z

133

Secondary air interaction with main flow in axial turbines  

E-Print Network (OSTI)

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

Zlatinov, Metodi B. (Metodi Blagoev)

2011-01-01T23:59:59.000Z

134

Axial Compression of a Hollow Cylinder Filled with a Foam  

Science Conference Proceedings (OSTI)

Presentation Title, Axial Compression of a Hollow Cylinder Filled with a Foam: A Porcupine ... Characterization of (Ti,Mg)N Thin Film Coatings Produced Via Physical Vapor Deposition ... Non-Toxic SPD Processed Ti Alloys for Orthopaedics.

135

Nonlinear Axially Symmetric Circulations in a Nearly Inviscid Atmosphere  

Science Conference Proceedings (OSTI)

The structure of certain axially symmetric circulations in a stably stratified, differentially heated, rotating Boussinesq fluid on a sphere is analyzed. A simple approximate theory [similar to that introduced by Schneider (1977)] is developed ...

Isaac M. Held; Arthur Y. Hou

1980-03-01T23:59:59.000Z

136

A simplified sizing and mass model for axial flow turbines  

SciTech Connect

An axial flow turbine mass model has been developed and used to study axial flow turbines for space power systems. Hydrogen, helium-xenon, hydrogen-water vapor, air, and potassium vapor working fluids have been investigated to date. The impact of construction material, inlet temperature, rotational speed, pressure ratio, and power level on turbine mass and volume has been analyzed. This paper presents the turbine model description and results of parametric studies showing general design trends characteristic of any axial flow machine. Also, a comparison of axial flow turbine designs using helium-xenon mixtures and potassium vapor working fluids, which are used in Brayton and Rankine space power systems, respectively, is presented. 9 refs., 4 figs., 2 tabs.

Hudson, S.L.

1989-01-01T23:59:59.000Z

137

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, Zoltn S. (Zoltn Sndor), 1972-

2001-01-01T23:59:59.000Z

138

PWR Axial Offset Anomaly (AOA) Guidelines, Revision 1  

Science Conference Proceedings (OSTI)

Axial offset anomaly (AOA) is defined as a significant negative axial offset deviation from the predicted nuclear design value. AOA results from the incorporation of boron within corrosion product deposits on the upper spans of high-duty pressurized water reactor (PWR) fuel assemblies. The consequences of this process are an erosion of shutdown margin and loss of operational flexibility by control room operators, particularly during power transients.

2004-06-28T23:59:59.000Z

139

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

DOE Green Energy (OSTI)

A comparative assessment of five potential hydrothermal-magma sites for this facet of the Thermal Regimes part of the CSDP has been prepared for the DOE Office of Basic Energy Sciences. The five sites are: The Geysers-Clear Lake, CA, Long Valley, CA, Rio Grande Rift, NM, Roosevelt Hot Springs, UT, and Salton Trough, CA. This site assessment study has drawn together background information (geology, geochemistry, geophysics, and energy transport) on the five sites as a preliminary stage to site selection. Criteria for site selection are that potential sites have identifiable, or likely, hydrothermal systems and associated magma sources, and the important scientific questions can be identified and answered by deep scientific holes. Recommendations were made.

Luth, W.C.; Hardee, H.C.

1980-11-01T23:59:59.000Z

140

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

DOE Green Energy (OSTI)

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

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

1990-12-01T23:59:59.000Z

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.


141

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

DOE Green Energy (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

142

Development of bakelite based Resistive Plate Chambers  

E-Print Network (OSTI)

A Comparative study has been performed on Resistive Plate Chambers made of different grades of bakelite paper laminates, produced and commercially available in India. The chambers, operated in the streamer mode using argon : tetrafluroethane : isobutane in 34:59:7 mixing ratio, are tested with cosmic rays for the efficiency and the stability with cosmic rays. A particular grade of bakelite (P-120, NEMA LI-1989 Grade XXX), used for high voltage insulation in humid conditions, was found to give satisfactory performance with stable efficiency of > 96% continuously for more than 110 days. A silicone treatment of the inner surfaces of the bakelite RPC is found to be necessary for operation of the detector.

S. Biswas; S. Bhattacharya; S. Bose; S. Chattopadhyay; S. Saha; M. K. Sharan; Y. P. Viyogi

2008-02-20T23:59:59.000Z

143

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

DOE Green Energy (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

144

Axially staggered seed-blanket reactor fuel module construction  

DOE Patents (OSTI)

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

Cowell, Gary K. (Monroeville, PA); DiGuiseppe, Carl P. (West Mifflin, PA)

1985-01-01T23:59:59.000Z

145

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

NLE Websites -- All DOE Office Websites (Extended Search)

Allan M. Cormack, Computerized Axial Tomography (CAT) Allan M. Cormack, Computerized Axial Tomography (CAT) and Magnetic Resonance Imaging (MRI) Resources with Additional Information magnetic resonance imaging system Computed axial tomography, commonly known as CAT scanning, was introduced in 1972. During a CAT scan, a large coil of x-ray tubes rotates around the patient's body, taking x-rays from all angles. A computer integrates all of these x-rays into a single, three-dimensional image on a television screen. The data can be saved on the computer. Allan M. Cormack, a high energy physicist at Tufts University, shared the 1979 Nobel Prize in Physiology and Medicine for his key work in developing the methods for CAT scanners. At the time of development, these methods were widely regarded as the most significant advance in medical radiography since the 1895 discovery of x-rays.

146

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

2013-03-28T23:59:59.000Z

147

Electrons Confined with an Axially Symmetric Magnetic Mirror Field  

Science Conference Proceedings (OSTI)

Low energy non-neutral electron plasmas were confined with an axially symmetric magnetic mirror field and an electrostatic potential to investigate the basic confinement properties of a simple magnetic mirror trap. As expected the confinement time became longer as a function of the mirror ratio. The axial electrostatic oscillations of a confined electron plasma were also observed. Obtained results suggested an improved scheme to accumulate low energy charged particles with the use of a magnetic mirror field, which would enable the investigation of electron-positron plasmas.

Higaki, H.; Ito, K.; Kira, K.; Okamoto, H. [Graduate School of Advanced Sciences of Matter, Hiroshima University 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8530 (Japan)

2008-08-08T23:59:59.000Z

148

Stability of magnetic configurations containing the toroidal and axial fields  

E-Print Network (OSTI)

Stability properties of magnetic-field configurations containing the toroidal and axial field are considered. The stability is treated by making use of linear analysis. It is shown that the conditions required for the onset of instability are essentially different from those given by the necessary condition $d (s B_{\\phi})/ds > 0$, where $s$ is the cylindrical radius. The growth rate of instability is calculated for a wide range of the parameters. We argue that the instability can operate in two different regimes depending on the strength of the axial field and the profile of the toroidal field.

Bonanno, Alfio

2007-01-01T23:59:59.000Z

149

CALCULATION OF PULSED KICKER MAGNETIC FIELD ATTENUATION INSIDE BEAM CHAMBERS  

NLE Websites -- All DOE Office Websites (Extended Search)

CALCULATION OF PULSED KICKER MAGNETIC FIELD ATTENUATION CALCULATION OF PULSED KICKER MAGNETIC FIELD ATTENUATION INSIDE BEAM CHAMBERS S. H. Kim January 8, 2001 1. Introduction and Summary The ceramic beam chambers in the sections of the kicker magnets for the beam injection and extraction in the Advanced Photon Source (APS) are made of alumina. The inner surface of the ceramic chamber is coated with a conductive paste. The choice of coating thickness is intended to reduce the shielding of the pulsed kicker magnetic field while containing the electromagnetic fields due to the beam bunches inside the chamber, and minimize the Ohmic heating due to the fields on the chamber [1]. The thin coating generally does not give a uniform surface resistivity for typical dimensions of the ceramic chambers in use. The chamber cross section is a circular or

150

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

151

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

152

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

153

Proceedings of the Axial Offset Anomaly (AOA) Science Workshop  

Science Conference Proceedings (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.

2000-06-27T23:59:59.000Z

154

Calculation of the nucleon axial charge in lattice QCD  

SciTech Connect

Protons and neutrons have a rich structure in terms of their constituents, the quarks and gluons. Understanding this structure requires solving Quantum Chromodynamics (QCD). However QCD is extremely complicated, so we must numerically solve the equations of QCD using a method known as lattice QCD. Here we describe a typical lattice QCD calculation by examining our recent computation of the nucleon axial charge.

D. B. Renner; R. G. Edwards; G. Fleming; Ph. Hagler; J. W. Negele; K. Orginos; A. V. Pochinsky; D. G. Richards; W. Schroers

2006-09-01T23:59:59.000Z

155

Inflationary Behaviour in Axial-symmetric Gravitational Collapse  

E-Print Network (OSTI)

We show that the interior of a charged, spinning black hole formed from a general axially symmetric gravitational collapse is unstable to inflation of both its mass and angular momentum parameters. Although our results are formulated in the context of $(2+1)$-dimensional black holes, we argue that they are applicable to $(3+1)$ dimensions.

J. S. F. Chan; R. B. Mann

1994-11-25T23:59:59.000Z

156

Hydrostatic self-aligning axial/torsional mechanism  

DOE Patents (OSTI)

The present invention is directed to a self-aligning axial/torsional loading mechanism for testing the strength of brittle materials which are sensitive to bending moments. Disposed inside said self-aligning loading mechanism is a frictionless hydrostatic ball joint with a flexure ring to accommodate torsional loads through said ball joint. 2 figs.

O' Connor, D.G.; Gerth, H.L.

1989-05-23T23:59:59.000Z

157

Hydrostatic self-aligning axial/torsional mechanism  

DOE Patents (OSTI)

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

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

1990-01-01T23:59:59.000Z

158

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

159

Proceedings of the Axial Offset Anomaly (AOA) Science Workshop  

SciTech Connect

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

160

Experiment plan for characterization of the properties of molten rock at atmospheric and elevated pressures: Magma Energy Research Project  

DOE Green Energy (OSTI)

Knowledge of the properties of molten rock (magma) is of importance to the Magma Energy Research Project of Sandia Laboratories. Facilities have been set up at Sandia to study the physical properties, chemistry, and corrosive nature of magma to 1600/sup 0/C and from atmospheric pressure to 4 kbar (400 MPa). Experiments at atmospheric pressure are being done in the presence of multicomponent gas mixtures to control the chemical activities of oxygen and sulfur. The high-pressure apparatus includes cold-seal small-volume pressure vessels (to 1100/sup 0/C and 1 kbar) and a large (750 cm/sup 3/ sample volume), internally heated pressure vessel (to 1600/sup 0/C and 4 kbar). The large vessel contains a number of penetrations for electrical leads and pressure lines, and is linked to a computer for data acquisition and control of experiments. Water and other dissolved volatiles (CO/sub 2/, CO, SO/sub 2/, S/sub 2/, H/sub 2/S, HCl, HF) have significant effects on all the properties of magma, and these effects will be studied in the high-pressure apparatus. Phase equilibria, viscosity, electrical conductivity, and materials compatibility will be the first properties to be examined under pressure. This report includes a review of the nature and chemical basis for the effects of dissolved volatiles on these properties of magma. 70 references, 10 figures.

Modreski, P.J.

1979-02-01T23:59:59.000Z

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.


161

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

DOE Green Energy (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

162

Performance Evaluation of the Magma 11.2MWe Binary Cycle Power Plant  

DOE Green Energy (OSTI)

The Magma 11.2 MWe geothermal power plant has been constructed and is currently in the final stages of shakedown. It should be starting up at the end of August, 1979. This project has many exciting features which will be reviewed in this presentation. Generally, the adjective ''exciting'' is not used in a technical report but, in this case, there is no way to disguise the enthusiasm of the organizations which conceived, designed, constructed and will operate the plant. It is an example of private venture capital invested in new technology to stimulate production of a significant new energy resource.

None

1979-09-01T23:59:59.000Z

163

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

DOE Green Energy (OSTI)

As part of a comparative assessment for the Continental Scientific Drilling Program, geophysical data were used, to characterize and evaluate potential magma-hydrothermal targets at five drill sites in the western United States. The sites include Roosevelt Hot Springs, Utah, the Rio Grande Rift, New Mexico, and The Geysers-Clear Lake, Long Valley, and Salton Trough areas, California. This summary discusses the size, depth, temperature, and setting of each potential target, as well as relvant scientific questions about their natures and the certainty of their existence.

Kasameyer, P.

1980-09-02T23:59:59.000Z

164

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

165

The hydrogen bubble chamber and the strange resonances  

SciTech Connect

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

166

DOSIMETRY, INSTRUMENTATION AND EXPOSURE CHAMBERS FOR DC MAGNETIC HELD STUDIES  

E-Print Network (OSTI)

C. -K. Yen ENGINEERING AND INSTRUMENTATION C. Dols D. NelsonLaboratory DOSIMETRY, INSTRUMENTATION AND EXPOSURE CHAMBERSLBL-9554 DOSIMETRY, INSTRUMENTATION AND EXPOSURE CHAMBERS

Tenforde, T.S.

2010-01-01T23:59:59.000Z

167

The hydrogen bubble chamber and the strange resonances  

DOE Green Energy (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

168

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

Office of Scientific and Technical Information (OSTI)

Luis Alvarez, the Hydrogen Bubble Chamber, Tritium, and Dinosaurs Resources with Additional Information Patents Luis Alvarez Courtesy Lawrence Berkeley National Laboratory 'Luis...

169

China New Energy Chamber of Commerce CNECC | Open Energy Information  

Open Energy Info (EERE)

China Zip 100052 Product A Chinese non-profit membership organization specializing in new energy industry, which is supervised by Chinese National Chamber of Commerce. References...

170

NIF Target Chamber Dedicated | National Nuclear Security Administratio...  

National Nuclear Security Administration (NNSA)

NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > About Us > Our History > NNSA Timeline > NIF Target Chamber Dedicated NIF Target...

171

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

172

Axial Ge/Si nanowire heterostructure tunnel FETs  

SciTech Connect

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

173

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

174

Designing Axial Flow Fan for Flow and Noise  

E-Print Network (OSTI)

A comprehensive finite element methodology is developed to predict the compressible flow performance of a non-symmetric 7-blade axial flow fan, and to quantify the source strength and sound pressure levels at any location in the system. The acoustic and flow performances of the fan are predicted simultaneously using a computational aero-acoustic technique combining transient flow analysis and noise propagation. The calculated sound power levels compare favorably with the measured sound power data per AMCA 300-96 code.

Subrata Roy; Phillip Cho; Fred Pri; International Off-highway

1999-01-01T23:59:59.000Z

175

Axial inlet conversion to a centrifugal compressor with magnetic bearings  

Science Conference Proceedings (OSTI)

NOVA's Alberta Gas Transmission Division transports natural gas via pipeline throughout the province of Alberta, Canada, exporting it to eastern Canada, US, and British Columbia. There is a continuing effort to operate the facilities and pipeline at the highest possible efficiency. One area being addressed to improve efficiency is compression of the gas. By improving compressor efficiency, fuel consumption and hence operating costs can be reduced. One method of improving compressor efficiency is by converting the compressor to an axial inlet configuration, a conversion that has been carried out more frequently in the past years. Concurrently, conventional hydrodynamic bearings have been replaced with magnetic bearings on many centrifugal compressors. This paper discusses the design and installation for converting a radial overhung unit to an axial inlet configuration, having both magnetic bearings and a thrust reducer. The thrust reducer is required to reduce axial compressor shaft loads, to a level that allows the practical installation of magnetic bearings within the space limitations of the compressor (Bear and Gibson, 1992).

Novecosky, T. (NOVA Corp., Edmonton, Alberta (Canada))

1994-01-01T23:59:59.000Z

176

Numerical Simulation on Forced Swirl Combustion Chamber in Diesel Engine  

Science Conference Proceedings (OSTI)

A concept of forced swirl combustion chamber in diesel engine is proposed in this paper. It can be used to enhance the intensity of swirl flow in the cylinder and accelerate the rate of air-fuel mixture process by designing the special structure in the ... Keywords: diesel engine, forced swirl, combustion chamber, simulation

Yong Shang; Fu-shui Liu; Xiang-rong Li

2010-12-01T23:59:59.000Z

177

Numerical Simulation on Forced Swirl Combustion Chamber in Diesel Engine  

Science Conference Proceedings (OSTI)

A concept of forced swirl combustion chamber in diesel engine is proposed in this paper. It can be used to enhance the intensity of swirl flow in the cylinder and accelerate the rate of air-fuel mixture process by designing the special structure in the ... Keywords: diesel engine, forced swirl, combustion chamber, simulation

Shang Yong; Liu Fu-shui; Li Xiang-rong

2011-02-01T23:59:59.000Z

178

Jet engine's speed controller with constant pressure chamber  

Science Conference Proceedings (OSTI)

The paper deals with an automatic system meant to control a jet engine's rotation speed, through the fuel injection's control, based on a constant pressure chamber controller. One has established the non-linear mathematical model (based on the motion ... Keywords: actuator, control, fuel injection, fuel pump, jet-engine, pressure chamber

Alexandru Nicolae Tudosie

2008-06-01T23:59:59.000Z

179

NIF Target Chamber Dedicated | National Nuclear Security Administration  

NLE Websites -- All DOE Office Websites (Extended Search)

NIF Target Chamber Dedicated | National Nuclear Security Administration NIF Target Chamber Dedicated | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > About Us > Our History > NNSA Timeline > NIF Target Chamber Dedicated NIF Target Chamber Dedicated June 11, 1999 Livermore, CA NIF Target Chamber Dedicated Secretary Richardson dedicates the National Ignition Facility target

180

Chemistry of radiation damage to wire chambers  

SciTech Connect

Proportional counters are used to study aspects of radiation damage to wire chambers (wire aging). Principles of low-pressure, rf plasma chemistry are used to predict the plasma chemistry in electron avalanches (1 atm, dc). (1) Aging is studied in CF{sub 4}/iC{sub 4}H{sub 10} gas mixtures. Wire deposits are analyzed by Auger electron spectroscopy. An apparent cathode aging process resulting in loss of gain rather than in a self-sustained current is observed in CF{sub 4}-rich gases. A four-part model considering plasma polymerization of the hydrocarbon, etching of wire deposits by CF{sub 4}, acceleration of deposition processes in strongly etching environments, and reactivity of the wire surface is developed to understand anode wire aging in CF{sub 4}/iC{sub 4}H{sub 10} gases. Practical guidelines suggested by the model are discussed. (2) Data are presented to suggest that trace amounts of Freons do not affect aging rates in either dimethyl ether or Ar/C{sub 2}H{sub 6}. Apparent loss of gain is explained by attachment of primary electrons to a continuously increasing concentration of Freon 11 (CCl{sub 3}F) in the counter gas. An increase in the concentration of Freon 11 in dimethyl ether is caused by a distillation process in the gas supply bottle and is a natural consequence of the unequal volatilities of the two compounds.

Wise, J.

1992-08-01T23:59:59.000Z

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

Coanda injection system for axially staged low emission combustors  

SciTech Connect

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

182

Effect of axial exposure distributions in burnup credit criticality analyses  

Science Conference Proceedings (OSTI)

Burnup credit is the application of the effects of fuel exposure or burnup to nuclear criticality considerations in the design of spent fuel transport and storage facilities. One unique issue in this design approach is the proper treatment of the axial variation in burnup experienced by pressurized-water-reactor fuel assemblies. This paper describes calculations and results quantifying this effect in the criticality analysis of spent fuel array geometries. Recommendations are made to provide guidance in evaluating these effects via three different approaches. Final selection of the analysis methodology would be dependent on the specific application and the degree of accuracy required.

Marotta, C.R. (Sandia National Labs., Albuquerque, NM (United States)); Brady, M.C (Oak Ridge National Lab., TN (United States)); Napolitano, D.G. (Yankee Atomic Electric Co., Boston, MA (United States))

1992-01-01T23:59:59.000Z

183

Effect of axial exposure distributions in burnup credit criticality analyses  

Science Conference Proceedings (OSTI)

Burnup credit is the application of the effects of fuel exposure or burnup to nuclear criticality considerations in the design of spent fuel transport and storage facilities. One unique issue in this design approach is the proper treatment of the axial variation in burnup experienced by pressurized-water-reactor fuel assemblies. This paper describes calculations and results quantifying this effect in the criticality analysis of spent fuel array geometries. Recommendations are made to provide guidance in evaluating these effects via three different approaches. Final selection of the analysis methodology would be dependent on the specific application and the degree of accuracy required.

Marotta, C.R. [Sandia National Labs., Albuquerque, NM (United States); Brady, M.C [Oak Ridge National Lab., TN (United States); Napolitano, D.G. [Yankee Atomic Electric Co., Boston, MA (United States)

1992-02-01T23:59:59.000Z

184

A conducting ball in an axial electric field  

E-Print Network (OSTI)

We describe the distribution of a charge, the electric moments of arbitrary order and the force acting on a conducting ball on the axis of the axial electric field. We determine the full charge and the dipole moments of the first order for a conducting ball in an arbitrary inhomogeneous harmonic electric field. All statements are formulated in the form of theorems with proofs basing on properties of the matrix of moments of the Legendre polynomials. The analysis and proof of these properties are presented in Appendix.

Alexander Savchenko

2012-12-26T23:59:59.000Z

185

Recovering partial conservation of axial current in diffractive neutrino scattering  

E-Print Network (OSTI)

A model of diffractive neutrino scattering is formulated in terms of the chiral hadronic current which is conserved in the limit of vanishing pion mass. This current has the correct singularity structure and, naturally, does not lead to contradictions with a partial conservation of the axial current (PCAC). In that respect we differ from earlier work in the literature, where a breakdown of PCAC had been reported. We show that such a breakdown of PCAC is an artifact of the hadronic current non-conservation in the model developed there.

V. A. Novikov; V. R. Zoller

2013-04-10T23:59:59.000Z

186

QN_CloudChamberV1.4  

NLE Websites -- All DOE Office Websites (Extended Search)

How to Build a Cosmic-Ray Cloud Chamber How to Build a Cosmic-Ray Cloud Chamber October 2008, Version 1.4 * QuarkNet version. Fermi National Accelerator Laboratory. * Instructions written by Jeremy Paschke, York High School and Anne Mary Teichert, Fermilab. * Model initially designed and built by Robert Peterson, Fermilab. If you have further questions, or improvements of your own you would like to share with the QuarkNet group, please contact: Jeremy Paschke, York High School Physics Instructor (jpaschke@elmhurst205.org), or Bob Peterson, Fermilab Education Specialist, (rspete@fnal.gov). Justification: Showing your class a working cloud chamber is one of the best ways to generate student interest in modern physics. The cloud chamber described below will display natural background radiation (muons generated by

187

SMALL CHAMBER MEASUREMENT OF CHEMICAL SPECIFIC EMISSION FACTORS...  

NLE Websites -- All DOE Office Websites (Extended Search)

temperature environmental chamber. The tests were all run at 25 C, 50% relative humidity (RH) and with an area-specific ventilation rate of 1.5 cubic meters per square meter...

188

BSA 08-14: A Multi-Anode Ionization Chamber  

BSA 08-14: A Multi-Anode Ionization Chamber. BNL Reference Number: BSA 08-14. Patent Status: U.S. Patent Number 7,858,949 was issued on December 28, 2010

189

A New Horizontal Gradient, Continuous Flow, Ice Thermal Diffusion Chamber  

Science Conference Proceedings (OSTI)

A continuous-flow, horizontal gradient, ice thermal diffusion chamber has been developed and tested for heterogeneous ice nucleation of aerosol particles under accurately controlled supersaturations and supercooling in the absence of a substrate. ...

E. M. Tomlinson; N. Fukuta

1985-12-01T23:59:59.000Z

190

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

E-Print Network (OSTI)

the key technical hurdles in SOFC development. Furthermore,bellow those of dual chamber SOFC, and increase even moresmaller than that of other SOFC, but the heat generated by

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

2003-01-01T23:59:59.000Z

191

Modeling chamber transport for heavy-ion fusion  

E-Print Network (OSTI)

representation of the molten-salt jets. Acknowledgments Thisto the target. Since molten-salt jets are planned to protectshielding, two meters of molten-salt jets inside the chamber

2002-01-01T23:59:59.000Z

192

A self-triggered readout for a time projection chamber  

E-Print Network (OSTI)

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

Werner, Andrew Thompson, 1981-

2004-01-01T23:59:59.000Z

193

Broadband impedance calculations of the TAN vacuum chamber for the Large Hadron Collider (LHC)  

E-Print Network (OSTI)

CHAMBER FOR THE LARGE HADRON COLLIDER (LHC) ? D. Li , G.chamber for the Large Hadron Collider (LHC). The TAN is the

Li, D.; Lambertson, G.; Turner, W.

2001-01-01T23:59:59.000Z

194

SCAMP Code -- Strategic Capacity Axial-Compressor Maintenance Program, Version 2.00  

Science Conference Proceedings (OSTI)

The Strategic Capacity Axial-Compressor Maintenance Program (SCAMP) spreadsheet provides combustion turbine operators with a low-cost, easy-to-install, easy-to-use program for monitoring combustion turbine axial compressor and overall turbine performance. It can be used to diagnose the condition of axial compressors and to determine the benefits of maintenance actions such as an off-line compressor wash. Important features of the SCAMP spreadsheet include the following: o Operates as a spreadsheet with m...

2000-12-12T23:59:59.000Z

195

PRE-SW Strategic Capacity Axial Compressor Maintenance Program (SCAMP) Version 3.0, Beta  

Science Conference Proceedings (OSTI)

The Strategic Capacity Axial-Compressor Maintenance Program (SCAMP) spreadsheet provides combustion turbine operators with a low-cost, easy-to-install, easy-to-use program for monitoring combustion turbine axial compressor and overall turbine performance. It can be used to diagnose the condition of axial compressors and to determine the benefits of maintenance actions such as an off-line compressor wash.Benefits & ...

2012-09-23T23:59:59.000Z

196

Axial dipolar dynamo action in the Taylor-Green vortex  

E-Print Network (OSTI)

We present a numerical study of the magnetic field generated by the Taylor-Green vortex. We show that periodic boundary conditions can be used to mimic realistic boundary conditions by prescribing the symmetries of the velocity and magnetic fields. This gives insight in some problems of central interest for dynamos: the possible effect of velocity fluctuations on the dynamo threshold, the role of boundary conditions on the threshold and on the geometry of the magnetic field generated by dynamo action. In particular, we show that an axial dipolar dynamo similar to the one observed in a recent experiment can be obtained with an appropriate choice of the symmetries of the magnetic field. The nonlinear saturation is studied and a simple model explaining the magnetic Prandtl number dependence of the super/sub critical nature of the dynamo transition is given.

Giorgio Krstulovic; Gentien Thorner; Julien-Piera Vest; Stephan Fauve; Marc Brachet

2011-09-19T23:59:59.000Z

197

Charmonium Decays to Axial-Vector Plus Pseudoscalar Mesons  

SciTech Connect

A sample of 3.79{times}10{sup 6} {psi}(2S) events is used to study the decays of charmonium to axial-vector plus pseudoscalar mesons. The branching fraction for the decay {psi}(2S){r_arrow}b{sup {plus_minus}}{sub 1} (1235){pi}{sup {minus_plus}} agrees with expectations based on scaling the corresponding J/{psi} branching fraction. Flavor-SU(3)-violating K{sub 1}(1270) -K{sub 1}(1400) asymmetries with opposite character for {psi}(2S) and J/{psi} decays are observed. This contrasting behavior cannot be accommodated by adjustments of the singlet-triplet mixing angle. {copyright} {ital 1999} {ital The American Physical Society}

Bai, J.Z.; Bian, J.G.; Chen, G.P.; Chen, J.C.; Chen, Y.; Chen, Y.B.; Chen, Y.Q.; Cheng, B.S.; Cui, X.Z.; Ding, H.L.; Dong, L.Y.; Du, Z.Z.; Gao, C.S.; Gao, M.L.; Gao, S.Q.; Gu, J.H.; Gu, S.D.; Gu, W.X.; Gu, Y.F.; Guo, Y.N.; Han, S.W.; Han, Y.; He, J.; He, J.T.; He, K.L.; Hu, G.Y.; Hu, H.M.; Hu, J.L.; Hu, Q.H.; Hu, T.; Hu, X.Q.; Huang, Y.Z.; Jiang, C.H.; Jin, Y.; Ke, Z.J.; Lai, Y.F.; Lang, P.F.; Li, C.G.; Li, D.; Li, H.B.; Li, J.; Li, P.Q.; Li, R.B.; Li, W.; Li, W.G.; Li, X.H.; Li, X.N.; Liu, H.M.; Liu, J.; Liu, R.G.; Liu, Y.; Lu, F.; Lu, J.G.; Luo, X.L.; Ma, E.C.; Ma, J.M.; Mao, H.S.; Mao, Z.P.; Meng, X.C.; Nie, J.; Qi, N.D.; Qi, X.R.; Qiu, J.F.; Qu, Y.H.; Que, Y.K.; Rong, G.; Shao, Y.Y.; Shen, B.W.; Shen, D.L.; Shen, H.; Shen, X.Y.; Sheng, H.Y.; Shi, H.Z.; Song, X.F.; Sun, F.; Sun, H.S.; Sun, Y.; Sun, Y.Z.; Tang, S.Q.; Tong, G.L.; Wang, F.; Wang, L.S.; Wang, L.Z.; Wang, M.; Wang, P.; Wang, P.L.; Wang, S.M.; Wang, T.J.; Wang, Y.Y.; Wei, C.L.; Wu, Y.G.; Xi, D.M.; Xia, X.M.; Xie, P.P.; Xie, Y.; Xie, Y.H.; Xu, G.F.; Xue, S.T.; Yan, J.; Yan, W.G.; Yang, C.M.; Yang, C.Y.; Yang, J.; Yang, X.F.; Ye, M.H.; Yu, C.S.; Yu, C.X.; Yu, G.W.; Yu, Z.Q.; Yuan, C.Z.; Yuan, Y.; Zhang, B.Y.; Zhang, C.C.; Zhang, D.H.; Zhang, D.; Zhang, H.L.; Zhang, J.; Zhang, J.W.; Zhang, L.S.; Zhang, Q.J.; Zhang, S.Q.; Zhang, Y.Y.; Zhao, D.X.; Zhao, H.W.; Zhao, J.W.; Zhao, M.; Zhao, W.R.; Zhao, Z.G.; Zheng, J.P.; Zheng, L.S.; Zheng, Z.P.; Zhou, B.Q.; Zhou, G.P.; Zhou, H.S.; Zhou, L.; Zhu, K.J.; Zhu, Q.M.; Zhu, Y.C.; Zhu, Y.S.; Zhuang, B.A. [Institute of High Energy Physics, Beijing 100039, People`s Republic of (China)] [Institute of High Energy Physics, Beijing 100039, People`s Republic of (China); Hitlin, D.G.; Kelsey, M.H.; Oyang, J.; Panetta, J.; Porter, F.; Weaver, M. [California Institute of Technology, Pasadena, California 91125 (United States)] [California Institute of Technology, Pasadena, California 91125 (United States); Chen, J.; Malchow, R.; Toki, W.; Yang, W. [Colorado State University, Fort Collins, Colorado 80523 (United States)] [Colorado State University, Fort Collins, Colorado 80523 (United States); Yu, Y.H. [Hangzhou Unv., Hangzhou 310028, People`s Republic of (China)] [Hangzhou Unv., Hangzhou 310028, People`s Republic of (China); Ban, Y. [Peking Unv. (China)] [Peking Unv. (China)

1999-09-01T23:59:59.000Z

198

Energy harvesting efficiency of piezoelectric flags in axial flows  

E-Print Network (OSTI)

Self-sustained oscillations resulting from fluid-solid instabilities, such as the flutter of a flexible flag in axial flow, can be used to harvest energy if one is able to convert the solid energy into electricity. Here, this is achieved using piezoelectric patches attached to the surface of the flag that convert the solid deformation into an electric current powering purely resistive output circuits. Nonlinear numerical simulations in the slender-body limit, based on an explicit description of the coupling between the fluid-solid and electric systems, are used to determine the harvesting efficiency of the system, namely the fraction of the flow kinetic energy flux effectively used to power the output circuit, and its evolution with the system's parameters. The role of the tuning between the characteristic frequencies of the fluid-solid and electric systems is emphasized, as well as the critical impact of the piezoelectric coupling intensity. High fluid loading, classically associated with destabilization by ...

Michelin, Sebastien

2012-01-01T23:59:59.000Z

199

Electro-deposition of Bi-axial Textured Layers on a Substrate ...  

The National Renewable Energy Laboratory has developed ... Solar Photovoltaic ... uniformly in one of the three axial directions in three-dimensional space, ...

200

Strangeness contribution to the vector and axial form factors of the nucleon  

E-Print Network (OSTI)

The strangeness contribution to the vector and axial form factors of the nucleon is presented for momentum transfers in the range $0.45Lab, and elastic $\

S. F. Pate; G. A. MacLachlan; D. W. McKee; V. Papavassiliou

2005-12-14T23:59:59.000Z

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.


201

Feedback Applications in Active Noise Control for Small Axial Cooling Fans.  

E-Print Network (OSTI)

??Feedback active noise control (ANC) has been applied as a means of attenuating broadband noise from a small axial cooling fan. Such fans are used (more)

Green, Matthew J 1978-

2006-01-01T23:59:59.000Z

202

Dark matter limits froma 15 kg windowless bubble chamber  

SciTech Connect

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

203

Method to calibrate fission chambers in Campbelling mode  

Science Conference Proceedings (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; Stphane Braud; Jean-Franois Villard

2011-06-01T23:59:59.000Z

204

Investigation of Argon Gas as a Potential Shock Attenuator in Z-IFE Chambers Using ALEGRA  

Science Conference Proceedings (OSTI)

Technical Paper / The Technology of Fusion Energy - Inertial Fusion Technology: Targets and Chambers

Sal B. Rodriguez; Jason Cook

205

A Continuous, In-Chamber Target Tracking and Engagement Approach for Laser Fusion  

Science Conference Proceedings (OSTI)

Technical Paper / The Technology of Fusion Energy - Inertial Fusion Technology: Targets and Chambers

Ron Petzoldt; Neil Alexander; Lane Carlson; Graham Flint; Dan Goodin; Jon Spalding; Mark Tillack

206

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

E-Print Network (OSTI)

Axial dispersion in segmented gas-liquid flow: Effects of alternating channel curvature Metin of channel curvature on the axial dispersion in segmented gas-liquid flows are studied computationally.1063/1.3531742 I. INTRODUCTION Segmented gas-liquid flow also known as Taylor flow has been studied extensively

Muradoglu, Metin

207

J. Ceomag. Geoelectr., 49, 1327-1342, 1997 Seafloor Electromagnetic Measurements above Axial Seamount,  

E-Print Network (OSTI)

in fractures or pipes. 1. Introduction AxialSeamountlieson the Juan deFucaRidge,about 500km westof-Eickelberg Seamount Chain (Johnson and Embley, 1990).Basalts fromAxial Seamount are broadly similar to those from-ocean ridge basalt (MORB) affinity. The volcano is the shallowestpart of the Juan de Fuca Ridge, indicating

Constable, Steve

208

The synchronous force control of a double-axial pneumatic actuating system  

Science Conference Proceedings (OSTI)

This paper presents the design of the synchronous force controller of a double-axial pneumatic actuating system. This system is ideally decomposed into two independent subsystems, and the coupling effect is considered as the noise effect. So, each ... Keywords: STC, double-axial pneumatic system, synchronous force control

Ying-Tsai Wang; Ming-Kun Chang

1999-07-01T23:59:59.000Z

209

Federation of Indian Chambers of Commerce & Industry (FICCI) | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Federation of Indian Chambers of Commerce & Industry (FICCI) Federation of Indian Chambers of Commerce & Industry (FICCI) Federation of Indian Chambers of Commerce & Industry (FICCI) March 20, 2007 - 11:37am Addthis Thank you Geoff (Pyatt) for that introduction. I'd like to thank FICCI for hosting this event and thank its leadership for their kind words. I'm very pleased to be here in India - and to be with all of you today. Since his very first days in office, President Bush has considered growing and strengthening the United States' bilateral relationship with India to be a top priority. The shared commitment of President Bush and Prime Minister Singh to building our relationship was evidenced by the historic strategic partnership initiatives announced during the President's visit here in March of last year.

210

Challenge Met as APS Sends Final Chambers to LCLS  

NLE Websites -- All DOE Office Websites (Extended Search)

A Marriage of Hardware and Hard Work A Marriage of Hardware and Hard Work Shaken but Not Stirred 2008 Rosalind Franklin Young Investigator Award The 2008 3-Way Meeting In R&D, Super X-rays Mark Many Spots APS News Archives: 2012 | 2011 | 2010 | 2009 2008 | 2007 | 2006 | 2005 2004 | 2003 | 2002 | 2001 2000 Subscribe to APS News rss feed Challenge Met as APS Sends Final Chambers to LCLS MAY 21, 2008 Bookmark and Share The final five (of 40) extruded aluminum vacuum chambers for the Linac Coherent Light Source (LCLS) undulator system have been shipped from Argonne National Laboratory - where the chambers were designed and assembled - to the Stanford Linear Accelerator Center, where the LCLS "will be the world's first x-ray free electron laser when it becomes operational in 2009. Pulses of x-ray laser light from LCLS will be many

211

Electromagnetic pulse generation within a petawatt laser target chamber  

Science Conference Proceedings (OSTI)

Recent work has been undertaken to characterize the electromagnatic pulse (EMP) generated by the high temperature high density plasma produced by a petawatt laser. This was to evaluate the susceptibility to malfunction and damage of equipment and diagnostics for the new Orion laser. EMP measurement were made using moebius loop antennas fitted inside the target chamber of the Vulcan petawatt laser at the Rutherford Appleton Laboratory. These show the EMP as a 63 MHz transient which decays from a peak magnetic field of around 4.3 A/m. A theoretical model presented assumes the EMP is produced by an impulse of 10{sup 12} electron emanating from the target, which charge the chamber wall causing it to ring at natural frequency. The theoretical model provides an estimate of the EMP measured in the Vulcan petawatt target chamber and will be used for the design of the Orion laser.

Mead, M.J.; Neely, D.; Gauoin, J.; Heathcote, R.; Patel, P. [Atomic Weapons Establishment, Aldermaston, Reading, RG7 4PR (United Kingdom); CLRC Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX (United Kingdom); Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2004-10-01T23:59:59.000Z

212

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

Science Conference Proceedings (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

213

Fuel subassembly leak test chamber for a nuclear reactor  

DOE Patents (OSTI)

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

Divona, Charles J. (Santa Ana, CA)

1978-04-04T23:59:59.000Z

214

The Laser Calibration System of the ALICE Time Projection Chamber  

E-Print Network (OSTI)

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

G. Renault; B. S. Nielsen; J. Westergaard; J. J. Gaardhje For The

2005-01-01T23:59:59.000Z

215

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

DOE Green Energy (OSTI)

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

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

2003-11-17T23:59:59.000Z

216

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)

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 A. R. Raffray1, G. Federici2, A. Hassanein3, D. Haynes4 1University Diego April 10, 2002 #12;April 10, 2002 A. R. Raffray, et al., Dynamic Chamber Armor Behavior in IFE

Raffray, A. René

217

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

DOE Patents (OSTI)

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

Walenta, Albert H. (Upton, NY)

1979-01-01T23:59:59.000Z

218

Modeling Chamber Transport for Heavy-Ion Fusion  

DOE Green Energy (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; Niller, D A C; Tabak, M; Yu, S S; Peterson, P F; Welch, D R; Rose, D V; Olson, C L

2002-08-02T23:59:59.000Z

219

Computation of azimuthal combustion instabilities in an helicopter combustion chamber  

E-Print Network (OSTI)

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

Nicoud, Franck

220

ARIES INERTIAL FUSION CHAMBER ASSESSMENT M. S. Tillack, F. Najmabadi  

E-Print Network (OSTI)

Washington, DC 20375 L. M. Waganer Boeing Company P.O. Box 516 St Louis, MO 63166-0516 and the ARIES Team to define design windows and explore in detail the tradeoffs for various chamber concepts. The work to better understand fundamental tradeoffs, characterize design windows and offer additional guidance to R

California at San Diego, University of

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

Axial couplings of heavy hadrons from domain-wall lattice QCD  

Science Conference Proceedings (OSTI)

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

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

2011-12-01T23:59:59.000Z

222

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

223

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

E-Print Network (OSTI)

9th European Fusion Theory Conference Non-local features of transport in the axial tokamak region J.P. Christiansen and P. Helander EURATOM/UKAEA Fusion Association, Culham Science Centre, Abingdon, Oxon OX14 3DB

224

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

225

Spin Polarized Photons and Di-leptons from Axially Charged Plasma  

E-Print Network (OSTI)

Axial charge in a QCD plasma is P- and CP-odd. We propose and study P- and CP-odd observables in photon and di-lepton emissions from an axially charged QCD plasma, which may provide possible experimental evidences of axial charge fluctuation and triangle anomaly in the plasma created in heavy-ion collisions. Our observables measure spin alignments of the emitted photons and di-leptons, and are shown to be related to the imaginary part of chiral magnetic conductivity at finite frequency-momentum, which ultimately arises from the underlying triangle anomaly of the QCD plasma with a finite axial charge density. We present an exemplar computation of these observables in strongly coupled regime using AdS/CFT correspondence.

Kiminad A. Mamo; Ho-Ung Yee

2013-07-30T23:59:59.000Z

226

Spin Polarized Photons and Di-leptons from Axially Charged Plasma  

E-Print Network (OSTI)

Axial charge in a QCD plasma is P- and CP-odd. We propose and study P- and CP-odd observables in photon and di-lepton emissions from an axially charged QCD plasma, which may provide possible experimental evidences of axial charge fluctuation and triangle anomaly in the plasma created in heavy-ion collisions. Our observables measure spin alignments of the emitted photons and di-leptons, and are shown to be related to the imaginary part of chiral magnetic conductivity at finite frequency-momentum, which ultimately arises from the underlying triangle anomaly of the QCD plasma with a finite axial charge density. We present an exemplar computation of these observables in strongly coupled regime using AdS/CFT correspondence.

Mamo, Kiminad A

2013-01-01T23:59:59.000Z

227

Short pulse high power microwave generation from an axially extracted virtual cathode oscillator  

Science Conference Proceedings (OSTI)

Preliminary experimental results of an axially extracted virtual cathode oscillator (vircator) built on the low impedance pulsed electron beam accelerator AMBICA-600 is reported. The AMBICA-600 pulsed power system mainly comprises of a coaxial waterline ...

Rishi Verma; Anurag Shyam; Tushar Patel; Y. C. Saxena

2011-02-01T23:59:59.000Z

228

Global Circulation in an Axially Symmetric Shallow Water Model Forced by Equinoctial Differential Heating  

Science Conference Proceedings (OSTI)

Solutions of an axially symmetric inviscid shallow-water model (SWM) on the earth forced by equinoctial differential heating are constructed using numerical integration of the time-dependent equations and analysis of their steady states. The ...

Ori Adam; Nathan Paldor

2009-05-01T23:59:59.000Z

229

Subdiffusive axial transport of granular materials in a long drum mixer  

E-Print Network (OSTI)

Granular mixtures rapidly segregate radially by size when tumbled in a partially filled horizontal drum. The smaller component moves toward the axis of rotation and forms a buried core, which then splits into axial bands. Models have generally assumed that the axial segregation is opposed by diffusion. Using narrow pulses of the smaller component as initial conditions, we have characterized axial transport in the core. We find that the axial advance of the segregated core is well described by a self-similar concentration profile whose width scales as $t^\\alpha$, with $\\alpha \\sim 0.3 < 1/2$. Thus, the process is subdiffusive rather than diffusive as previously assumed. We find that $\\alpha$ is nearly independent of the grain type and drum rotation rate within the smoothly streaming regime. We compare our results to two one-dimensional PDE models which contain self-similarity and subdiffusion; a linear fractional diffusion model and the nonlinear porous medium equation.

Zeina S. Khan; Stephen W. Morris

2004-08-28T23:59:59.000Z

230

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

E-Print Network (OSTI)

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

Botros, Barbara Brenda

2008-01-01T23:59:59.000Z

231

Hadley Circulations in RadiativeConvective Equilibrium in an Axially Symmetric Atmosphere  

Science Conference Proceedings (OSTI)

Hadley circulations in radiativeconvective equilibrium are investigated using an idealistic axially symmetric model. Calculations show that the distribution of temperature in the Hadley cell is controlled by the moist process; the vertical ...

Masaki Satoh

1994-07-01T23:59:59.000Z

232

Sensitivity of 5-cm Wavelength Polarimetric Radar Variables to Raindrop Axial Ratio and Drop Size Distribution  

Science Conference Proceedings (OSTI)

The sensitivity of polarimetric variables at a 5-cm wavelength to raindrop size and axial ratio is examined using T-matrix modeling of the scattering process for gamma raindrop size distributions fitted to tropical rainfall collected at Darwin, ...

T. D. Keenan; L. D. Carey; D. S. Zrni?; P. T. May

2001-03-01T23:59:59.000Z

233

Axial Wind Effects on Stratification and Longitudinal Salt Transport in an Idealized, Partially Mixed Estuary  

Science Conference Proceedings (OSTI)

A 3D hydrodynamic model [Regional Ocean Model System (ROMS)] is used to investigate how axial wind influences stratification and to explore the associated longitudinal salt transport in partially mixed estuaries. The model is configured to ...

Shih-Nan Chen; Lawrence P. Sanford

2009-08-01T23:59:59.000Z

234

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

235

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

SciTech Connect

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

236

Vermont Yankee's benefits and concerns operating with Axially zoned GE9 fuel  

Science Conference Proceedings (OSTI)

Vermont Yankee (VY) is a 368-assembly, D-lattice, boiling water reactor (BWR)/4. The current cycle 16 contains 252 GE9 assemblies with axial zoning of gadolinium and enrichment, 112 GE8 assemblies with axially zoned gadolinium, and 4 Siemens 9 x 9-IX lead qualification assemblies. In this paper, the performance of the GE9-dominated core is evaluated against previous cores containing less sophisticated fuel designs.

Woehlke, R.A. (Yankee Atomic Electric Co., Bolton, MA (United States))

1993-01-01T23:59:59.000Z

237

Combustion chamber and thermal vapor stream producing apparatus and method  

DOE Patents (OSTI)

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

Sperry, John S. (Houston, TX); Krajicek, Richard W. (Sugar Land, TX); Cradeur, Robert R. (Spring, TX)

1978-01-01T23:59:59.000Z

238

Study of the response of low pressure ionization chambers  

E-Print Network (OSTI)

The Beam Loss Monitoring System (BLM) of the Large Hadron Collider (LHC) is based on parallel plate Ionization Chambers (IC) with active volume 1.5l and a nitrogen filling gas at 0.1 bar overpressure. At the largest loss locations, the ICs generate signals large enough to saturate the read-out electronics. A reduction of the active volume and filling pressure in the ICs would decrease the amount of charge collected in the electrodes, and so provide a higher saturation limit using the same electronics. This makes Little Ionization Chambers (LIC) with both reduced pressure and small active volume a good candidate for these high radiation areas. In this contribution we present measurements performed with several LIC monitors with reduced active volume and various filling pressures. These detectors were tested under various conditions with different beam setups, with standard LHC ICs used for calibration purposes

Nebot Del Busto, E; Effinger, E; Grishin, V; Herranz Alvarez, J

2012-01-01T23:59:59.000Z

239

Destruction of nuclear graphite using closed chamber incineration  

Science Conference Proceedings (OSTI)

Closed chamber incineration (CCI) is a novel technique by which irradiated nuclear graphite may be destroyed without the risk of radioactive cation release into the environment. The process utilizes an enclosed combustion chamber coupled with molten carbonate fuel cells (MCFCs). The transport of cations is intrinsically suppressed by the MCFCs, such that only the combustion gases are conducted through for release to the environment. An example CCI design was developed which had as its goal the destruction of graphite fuel elements from the Fort St. Vrain reactor (FSVR). By employing CCI, the volume of high level waste from the FSVR will be reduced by approximately 87 percent. Additionally, the incineration process will convert the SiC coating on the FSVR fuel particles to SiO{sub 2}, thus creating a form potentially suitable for direct incorporation in a vitrification process stream. The design is compact, efficient, and makes use of currently available technology.

Senor, D.J.; Hollenberg, G.W.; Morgan, W.C. [Pacific Northwest Lab., Richland, WA (United States); Marianowski, L.G. [Institute of Gas Technology, Chicago, IL (United States)

1994-03-01T23:59:59.000Z

240

Tobacco smoke aging in the presence of ozone: a room-sized chamber...  

NLE Websites -- All DOE Office Websites (Extended Search)

Tobacco smoke aging in the presence of ozone: a room-sized chamber study Title Tobacco smoke aging in the presence of ozone: a room-sized chamber study Publication Type Journal...

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

A Continuous-Flow Diffusion Chamber for Airborne Measurements of Ice Nuclei  

Science Conference Proceedings (OSTI)

A continuous-flow thermal gradient diffusion chamber was developed for operating in an aircraft and detecting ice nucleating aerosol particles in real time. The chamber volume is the annular space between two vertically oriented concentric ...

David C. Rogers; Paul J. DeMott; Sonia M. Kreidenweis; Yalei Chen

2001-05-01T23:59:59.000Z

242

Using sputter coated glass to stabilize microstrip gas chambers  

DOE Patents (OSTI)

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

Gong, Wen G. (Albany, CA)

1997-01-01T23:59:59.000Z

243

Aging Chamber Report Tool (ACRT) Version 5.0  

Science Conference Proceedings (OSTI)

The 230kV Accelerated Aging Chamber is a multi-year test of more than 50 polymer and fiberglass components. Photographic inspections occur twice a year. Thousands of photographs accumulate making conventional reports difficult to read. This reporting tool enables the reader to jump from component to component and inspection to inspection. The reader can easily compare components at different levels of aging. This tool will make reviewing the important results of this ...

2012-09-20T23:59:59.000Z

244

Aging Chamber Report Tool (ACRT) v6.0  

Science Conference Proceedings (OSTI)

The 230kV Accelerated Aging Chamber is a multi-year test of more than 50 polymer and fiberglass components. Photographic inspections occur twice a year. Thousands of photographs accumulate making conventional reports difficult to read. This reporting tool enables the reader to jump from component to component and inspection to inspection. The reader can easily compare components at different levels of aging. This tool will make reviewing the important results of this ...

2013-12-10T23:59:59.000Z

245

High Rate Resistive Plate Chamber for LHC detector upgrades  

E-Print Network (OSTI)

The limitation of the detection rate of standard bakelite resistive plate chambers (RPC) used as muon detectors in the LHC experiments has prevented the use of such detectors in the high rate regions in both CMS and ATLAS detectors. One alternative to these detectors are RPCs made with low resistivity glass plates ($10^{10} {\\rm \\Omega .cm}$), a beam test at DESY has shown that such detectors can operate at few thousand Hz/cm$^2$ with high efficiency(> 90%)

Y. Haddad; G. Grenier; I. Laktineh; N. Lumb; S. Cauwenbergh

2012-11-24T23:59:59.000Z

246

Recommendations for Addressing Axial Burnup in the PWR Burnup Credit Analyses  

SciTech Connect

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

Wagner, J.C.

2002-10-23T23:59:59.000Z

247

LAYOUT AND SIZING OF ESF ALCOVES AND REFUGE CHAMBERS  

SciTech Connect

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

John Beesley and Romeo S. Jurani

1995-08-25T23:59:59.000Z

248

Test with cosmic rays of the GEM chambers for the LHCb muon system produced in Cagliari  

E-Print Network (OSTI)

The inner region of the first LHCb muon station will be equipped with twelve Gas Electron Multiplier chambers. The seven chambers produced in Cagliari were studied for several days each using cosmic rays. We measured the efficiency, timing resolution, and uniformity, cluster-size and out-of-time multiplicity. We find all seven chambers perform well.

Bonivento, W; Oldeman, R G C

2007-01-01T23:59:59.000Z

249

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

SciTech Connect

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

250

Cerebral imaging using $sup 68$Ga DTPA and the U.C.S.F. multiwire proportional chamber positron camera  

SciTech Connect

A multiwire proportional chamber positron camera consisting of four 48 x 48 cm$sup 2$ detectors linked to a small digital computer has been designed, constructed, and characterized. Initial clinical application to brain imaging using $sup 68$Ga DTPA in 10 patients with brain tumors is described. Tomographic image reconstruction is accomplished by an algorithm determining the intersection of the annihilation photon paths in planes of interest. Final image processing utilizes uniformity correction, simple thresholding, and smoothing. The positron brain images were compared to conventional scintillation brain scans and x-ray computerized axial tomograms (CAT) in each case. The positron studies have shown significant mitigation of confusing superficial activity resulting from craniotomy in comparison to conventional brain scans. Central necrosis of lesions observed in the positron images, but not in the conventional scans, has been confirmed in CAT. Modifications of the camera are being implemented to improve image quality, and these changes combined with the tomography inherent in the positron scans are anticipated to result in images superior in information content to conventional brain scans. (auth)

Hattner, R.S.; Lim, C.B.; Swann, S.J.; Kaufman, L.; Perez-Mendez, V.; Chu, D.; Huberty, J.P.; Price, D.C.; Wilson, C.B.

1975-12-01T23:59:59.000Z

251

MagmaHeatNS1D: One-dimensional visualization numerical simulator for computing thermal evolution in a contact metamorphic aureole  

Science Conference Proceedings (OSTI)

MagmaHeatNS1D is an IDL (Interactive Data Language) program that is aimed at numerically modeling heat transfer from an igneous intrusion to its host rocks and providing important thermal state information for minerals and organic matters in a contact ... Keywords: Contact metamorphism, Heat transfer model, Igneous intrusion, Maturation, Numerical simulation, Thermal evolution

Dayong Wang

2013-04-01T23:59:59.000Z

252

Los Alamos honored by Española Valley Chamber of Commerce  

NLE Websites -- All DOE Office Websites (Extended Search)

LANL Honored By Española Valley Chamber of Commerce LANL Honored By Española Valley Chamber of Commerce Community Connections: Our link to Northern New Mexico Communities Latest Issue:Dec. 2013 - Jan. 2014 All Issues » submit Los Alamos honored by Española Valley Chamber of Commerce The Espanola Valley Chamber of Commerce recognized the Lab for its support to the chamber and the entire Espanola Valley with a President's Choice Award. February 1, 2013 dummy image Read our archives. Contacts Editor Linda Anderman Email Community Programs Office Kurt Steinhaus Email The Lab received the award for efforts in a variety of areas. In late January, the Espanola Valley Chamber of Commerce recognized the Lab for its support to the chamber and the entire Espanola Valley with a President's Choice Award. Kurt Steinhaus with the Lab's Community

253

Charged Axially Symmetric Solution, Energy and Angular Momentum in Tetrad Theory of Gravitation  

E-Print Network (OSTI)

Charged axially symmetric solution of the coupled gravitational and electromagnetic fields in the tetrad theory of gravitation is derived. The metric associated with this solution is an axially symmetric metric which is characterized by three parameters ``$ $the gravitational mass $M$, the charge parameter $Q$ and the rotation parameter $a$". The parallel vector fields and the electromagnetic vector potential are axially symmetric. We calculate the total exterior energy. The energy-momentum complex given by M{\\o}ller in the framework of the Weitzenb$\\ddot{o}$ck geometry ``$ ${\\it characterized by vanishing the curvature tensor constructed from the connection of this geometry}" has been used. This energy-momentum complex is considered as a better definition for calculation of energy and momentum than those of general relativity theory. The energy contained in a sphere is found to be consistent with pervious results which is shared by its interior and exterior. Switching off the charge parameter, one finds that no energy is shared by the exterior of the charged axially symmetric solution. The components of the momentum density are also calculated and used to evaluate the angular momentum distribution. We found no angular momentum contributes to the exterior of the charged axially symmetric solution if zero charge parameter is used.

Gamal G. L. Nashed

2005-01-01T23:59:59.000Z

254

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

Science Conference Proceedings (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

255

The Time Projection Chamber for the ALICE Experiment  

E-Print Network (OSTI)

The Time Projection Chamber of the ALICE Experiment has been installed in the experimental setup in the underground area at the Large Hadron Collider at CERN in Geneva. The Alice TPC ReadOut (ALTRO) chip implements intelligent signal processing on the Front-End-Electronics. During the years of 2007 and 2008 commissioning and calibration of the TPC have been carried out with cosmic rays, radioactive Krypton isotopes and with tracks produced by a UV laser system. In addition to these in this publication we present first results on energy loss measurements and on the momentum resolution.

C. Lippmann; the ALICE TPC collaboration

2008-09-30T23:59:59.000Z

256

Global Calculations of Ground-State Axial Shape Asymmetry of Nuclei  

SciTech Connect

Important insight into the symmetry properties of the nuclear ground-state (gs) shape is obtained from the characteristics of low-lying collective energy-level spectra. In the 1950s, experimental and theoretical studies showed that in the gs many nuclei are spheroidal in shape rather than spherical. Later, a hexadecapole component of the gs shape was identified. In the 1970-1995 time frame, a consensus that reflection symmetry of the gs shape was broken for some nuclei emerged. Here we present the first calculation across the nuclear chart of axial symmetry breaking in the nuclear gs. We show that we fulfill a necessary condition: Where we calculate axial symmetry breaking, characteristic gamma bands are observed experimentally. Moreover, we find that, for those nuclei where axial asymmetry is found, a systematic deviation between calculated and measured masses is removed.

Moeller, Peter [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Bengtsson, Ragnar; Carlsson, B. Gillis; Olivius, Peter [Department of Mathematical Physics, Lund Institute of Technology, P.O. Box 118, SE-22100 Lund (Sweden); Ichikawa, Takatoshi [Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), Tokai-mura, Naka-gun, Ibaraki, 319-1195 (Japan)

2006-10-20T23:59:59.000Z

257

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

258

Anechoic Chamber of the National Research Council of Canada  

Science Conference Proceedings (OSTI)

The anechoic chamber built recently by the National Research Council (approximately 241717 ft) incorporates a number of design features which reduce substantially the cost of the structure with no sacrifice in performance. An appreciable part of the saving was achieved by a simplification in the preparation and mounting of the wedges. (The cost of treatment was $3.53 per square foot.) The wedges were sprayed with three coats of lacquer to improve the binding of the Fiberglas and thus facilitate handling and avoid shedding. The only appreciable effect on the absorption coefficient for normal incidence was to lower the cutoff frequency from 85 cps to 80 cps. The wedges were wrapped in cheese cloth which was then stitched by means of hot paraffin. Instead of pre?mounting the wedges on a base individual holders were stamped out of sheet metal and stapled to the furring strips. The wedges could then be mounted in about 8 sec each. The inner room is of frame construction with a removable catwalk hung from the ceiling. The performance of the completed chamber was measured by the standard inverse square law method.

N. Olson; G. J. Thiessen; E. A. G. Shaw; T. F. W. Embleton

1959-01-01T23:59:59.000Z

259

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

260

Slag monitoring system for combustion chambers of steam boilers  

SciTech Connect

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

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

Effects of solution exposure on the combined axial-shear behaviour of unidirectional CFRP rods  

E-Print Network (OSTI)

This is the peer reviewed version of Scott, P. and Lees, J.M. (2012) "Effects of solution exposure on the combined axial-shear behaviour of unidirectional CFRP rods" Composites Part A: Applied science and manufacturing v. 43A, (9) 15991611 which... has been published on http://dx.doi.org/10.1016/j.compositesa.2012.03.027 Effects of solution exposure on the combined axial-shear behaviour of unidirectional CFRP rods P. Scott1 and J.M. Lees2 1 Department of Engineering, University...

Lees, J. M.; Scott, P

2012-04-06T23:59:59.000Z

262

BIO-BAG Type Cfj Environmental Chamber DESCRIPTION  

E-Print Network (OSTI)

BIO-BAG Type Cfj is a disposable, individual environmental chamber and a gas generator, consisting of one tablet of potassium borohydride-sodium bicarbonate and an ampule of hydrochloric acid, which when activated in the sealed BIO-BAG chamber provides a microaerophilic atmosphere. INTENDED USE BIO-BAG Type Cfj is designed to provide a microaerophilic environment suitable for the isolation of Campylobacter jejuni, formerly known as C. fetus subsp. jejuni (Cfj), from clinical specimens or subcultures from selective media. When used as directed, BIO-BAG Type Cfj will provide an atmosphere that has been shown to provide optimum growth of C. jejuni. 1,2 SUMMARY AND EXPLANATION Campylobacter jejuni has been recognized as a common enteric pathogen. 2,4,7,8 This organism is a true microaerophile and a capnophilic atmosphere has been shown to enhance growth. 5 Use of a selective medium containing 5 % sheep blood and a combination of antimicrobial agents and incubation at 42C provides conditions favorable for the selective isolation of C. jejuni from intestinal flora. 3,6 Under ideal conditions, characteristic colonies may be observed in 24 to 48 h, 1,2,5 Each BIO-BAG Type Cfj system allows cultures to be set up and observed for growth individually, so that appropriate atmospheric conditions are not interrupted. Exposure to atmospheric oxygen may interfere with the growth of more oxygen-sensitive strains. 5 PRINCIPLE OF THE PROCEDURE A microaerophilic-capnophilic atmosphere is provided in each sealed BIO-BAG Type Cfj system. A self-contained generator consists of an ampule of a weak hydrochloric acid solution and a gas generator tablet. When the ampule is crushed, the tablet is then activated. A portion of atmospheric oxygen in the chamber is utilized in the reaction. The resulting atmosphere is conducive to the isolation and cultivation of C. jejuni. 1,2 Each BIO-BAG Type Cfj system is disposable and designed to be used only once.

unknown authors

1999-01-01T23:59:59.000Z

263

Charge-Focusing Readout of Time Projection Chambers  

E-Print Network (OSTI)

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

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

2013-04-02T23:59:59.000Z

264

Charge-Focusing Readout of Time Projection Chambers  

E-Print Network (OSTI)

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

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

2013-01-01T23:59:59.000Z

265

Radiation damage control in the BNL hypernuclear spectrometer drift chamber system  

SciTech Connect

A high rate drift chamber system has been in use at the BNL hypernuclear spectrometer system for the past three years. Some of the chambers have accumulated charge doses up to about 0.2 C/cm-wire without showing external signs of aging. The system design and performance will be discussed as well as the results of some laboratory drift chamber aging tests. 5 refs., 9 figs.

Pile, P.H.

1986-01-01T23:59:59.000Z

266

Original articles: Vortex states in axially symmetric superconductors in applied magnetic field  

Science Conference Proceedings (OSTI)

We solve analytically the linearized Ginzburg-Landau (GL) equation in the presence of an uniform magnetic field with cylindrical boundary conditions. The solution of the non-linear GL equation is provided as an expansion in the basis of linearized solutions. ... Keywords: Axial magnetic field, Mesoscopic superconductivity, Nonlinear Ginzburg-Landau equation, Vortex

Andrei Ludu; Milorad V. Miloevi?; Francois M. Peeters

2012-03-01T23:59:59.000Z

267

Low inductance axial flux BLDC motor drive for more electric aircraft  

Science Conference Proceedings (OSTI)

As the aircraft technology is moving towards more electric architecture, use of electric motors in aircraft is increasing.12 Axial-flux BLDC motors are becoming popular in aero application because of their ability to meet the demand of light weight, ...

Sukumar De; Milan Rajne; Srikant Poosapati; Chintan Patel; K. Gopakumar

2011-03-01T23:59:59.000Z

268

Influence of induced axial magnetic field on plasma dynamics and radiative characteristics of Z pinches  

SciTech Connect

The influence of an induced axial magnetic field on plasma dynamics and radiative characteristics of Z pinches is investigated. An axial magnetic field was induced in a novel Z-pinch load: a double planar wire array with skewed wires (DPWAsk), which represents a planar wire array in an open magnetic configuration. The induced axial magnetic field suppressed magneto-Rayleigh-Taylor (MRT) instabilities (with m = 0 and m = 1 instability modes) in the Z-pinch plasma. The influence of the initial axial magnetic field on the structure of the plasma column at stagnation was manifested through the formation of a more uniform plasma column compared to a standard double planar wire array (DPWA) load [V. L. Kantsyrev et al., Phys. Plasmas 15, 030704 (2008)]. The DPWAsk load is characterized by suppression of MRT instabilities and by the formation of the sub-keV radiation pulse that occurs before the main x-ray peak. Gradients in plasma parameters along the cathode-anode gap were observed and analyzed for DPWAsk loads made from low atomic number Z (Al) and mid-Z (brass) wires.

Kantsyrev, V. L.; Esaulov, A. A.; Safronova, A. S.; Osborne, G. C.; Shrestha, I.; Weller, M. E.; Stafford, A.; Shlyaptseva, V. V. [Physics Department, University of Nevada, Reno, Nevada 89557 (United States); Velikovich, A. L. [Plasma Physics Division, Naval Research Laboratory, Washington, D.C. 20375 (United States); Rudakov, L. I. [Icarus Research Inc., Bethesda, Maryland 20824 (United States); Williamson, K. M. [Physics Department, University of Nevada, Reno, Nevada 89557 (United States); Plasma Engineering Research Laboratory, Texas A and M University, Corpus Christi, TX 78412 (United States)

2011-10-15T23:59:59.000Z

269

A computational study of axial dispersion in segmented gas-liquid flow Metin Muradoglua  

E-Print Network (OSTI)

A computational study of axial dispersion in segmented gas-liquid flow Metin Muradoglua Department-dimensional gas-liquid flow is studied computationally using a finite-volume/front-tracking method. The effects models. © 2007 American Institute of Physics. DOI: 10.1063/1.2750295 I. INTRODUCTION Segmented gas-liquid

Muradoglu, Metin

270

An Axial-Flow Cyclone for Aircraft-Based Cloud Water Sampling  

Science Conference Proceedings (OSTI)

A new aircraft-based cloud water collection system has been developed to provide samples of cloud water for chemical analysis. The collection system makes use of centrifugal separation in an axial-flow cyclone to remove cloud drops from the ...

Derek J. Straub; Jeffrey L. Collett Jr.

2004-12-01T23:59:59.000Z

271

Segmentation of female pelvic organs in axial magnetic resonance images using coupled geometric deformable models  

Science Conference Proceedings (OSTI)

The segmentation of pelvic structures in magnetic resonance (MR) images of the female pelvic cavity is a challenging task. This paper proposes the use of three novel geometric deformable models to segment the bladder, vagina and rectum in axial MR images. ... Keywords: Bladder, Image segmentation, Imaging appearance, Level set, Prior shape knowledge, Rectum, Vagina

Zhen Ma; Renato M. Natal Jorge; Teresa Mascarenhas; JoO Manuel R. S. Tavares

2013-05-01T23:59:59.000Z

272

The existence theorem for steady Navier--Stokes equations in the axially symmetric case  

E-Print Network (OSTI)

We study the nonhomogeneous boundary value problem for Navier-Stokes equations of steady motion of a viscous incompressible fluid in a three-dimensional bounded multiply connected domain. We prove that this problem has a solution in some axially symmetric cases, in particular, when all components of the boundary intersect the axis of symmetry.

Mikhail Korobkov; Konstantin Pileckas; Remigio Russo

2011-10-28T23:59:59.000Z

273

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

E-Print Network (OSTI)

The objective of this study is to measure the response of the orifice meter to known upstream flow field disturbances generated by a concentric tube flow conditioner and a vane-type swirl generator. These disturbances are characterized by flan measuring the axial and tangential velocity profiles at the upstream tap with no orifice plate present. Two different flow rates are examined which correspond to Reynolds numbers of 91,100 and 120,000 in a 50.8 mm diameter pipe. Eight orifice plates 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 the discharge coefficient. The axial momentum distribution is quantified by calculating the second order moment of axial momentum (91 2[U]) from the velocity profile data. Swirl is quantified by determining the centripetal acceleration flux of the flow, also from the velocity profile data. Surface fits indicating the variation of discharge coefficient as a function of P ratio and 9i2[U] or swirl number are developed. These are useful in evaluating variations in the discharge coefficient for flows where the inlet velocity profile has been measured.

Hauglie, Jayden Edward

1994-01-01T23:59:59.000Z

274

Analysis and Design of a High Power Density Axial Flux Permanent Magnet Linear Synchronous Machine Used for Stirling System  

Science Conference Proceedings (OSTI)

a high power density axial flux permanent magnet linear synchronous machine and the stirling system will be introduced. This machine is a tubular axial flux permanent magnet machine. It comprises two parts: stator and mover. With the 2D finite-element ... Keywords: permanent magnet, stirling engine, linear motor

Ping Zheng; Xuhui Gan; Lin Li

2010-09-01T23:59:59.000Z

275

Dynamic chamber armor behavior in IFE and MFE A.R. Raffray a,  

E-Print Network (OSTI)

Dynamic chamber armor behavior in IFE and MFE A.R. Raffray a, 1, G. Federici b , A. Hassanein c , D., Madison, WI 53706-1687, USA Abstract The chamber wall armor is subject to demanding conditions in both the requirements on armor imposed by the operating conditions in IFE and MFE, including energy deposition density

Raffray, A. René

276

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

E-Print Network (OSTI)

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

Yang, Vigor

277

Ionization statistics and diffusion: analytical estimate of their contribution to spatial resolution of drift chambers  

SciTech Connect

The spatial resolution of a drift chamber often is the foremost design parameter. The calculation described here - a design tool - permits us to estimate the contributions of ionization statistics and diffusion to the spatial resolution when actually sampling the drift pulse waveform. Useful formulae are derived for the cylindrical and jet-chamber cell geometries.

Tarnopolsky, G.J.

1983-01-01T23:59:59.000Z

278

Commissioning an animal preference chamber for behavioral studies with laying hens exposed to atmospheric ammonia  

Science Conference Proceedings (OSTI)

An environmental preference chamber (EPC) with four double-tiered compartments (C1-C4), each capable of being controlled to distinct ammonia (NH"3) concentrations and temperature, was designed, fabricated and commissioned. Preference chambers are commonly ... Keywords: Ambient conditions, Animal welfare, Automatic control, Cross-contamination

G. T. Sales, A. R. Green, R. S. Gates

2013-07-01T23:59:59.000Z

279

OPERATIONAL WINDOWS FOR DRY-WALL AND WETTED-WALL IFE CHAMBERS  

E-Print Network (OSTI)

OPERATIONAL WINDOWS FOR DRY-WALL AND WETTED-WALL IFE CHAMBERS F. NAJMABADI* University the trade- offs, to develop operational windows for chamber con- cepts, and to identify high the injection process; (d) for relatively low yield targets ( 250 MJ), an operational window with no buffer gas

California at San Diego, University of

280

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Chamber of Commerce Biofuels Dialogue Series: Outlook for an Chamber of Commerce Biofuels Dialogue Series: Outlook for an Emerging Global Biofuels Market U.S. Chamber of Commerce Biofuels Dialogue Series: Outlook for an Emerging Global Biofuels Market January 29, 2008 - 10:53am Addthis Remarks as Prepared For Delivery by Secretary Bodman Thank you very much, Bruce, for that kind introduction. My thanks also to Tom Donahue and the leadership of the Chamber for inviting me to be with you today. I was quite pleased to hear that the Chamber was sponsoring this event. As anyone who knows me - or has heard me speak recently - can tell you, the biofuels industry is a favorite topic of mine. In my view, advanced biofuels offer tremendous promise for helping our nation to bring about a new energy future-one that is cleaner, more sustainable, more affordable,

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

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

The American Chamber of Commerce of Trinidad & Tobago The American Chamber of Commerce of Trinidad & Tobago The American Chamber of Commerce of Trinidad & Tobago May 13, 2008 - 12:00pm Addthis Remarks As Prepared for Delivery by Secretary Bodman Thank you, Raymond. I appreciate the Chamber organizing this gathering this morning. The American Chamber here on Trinidad and Tobago is an important regional voice in support of the free market, so I want to commend you for hosting the Business Future of the Americas conference next month. Having spent most of my career in the private sector, it is always rewarding to be among colleagues from the business community. I'm also quite pleased to be back in Trinidad & Tobago, having done business here during my time at Cabot Corporation. I've always been impressed with this nation's government, its people and

282

MHK Technologies/Multi Resonant Chambers MRC 1000 | Open Energy Information  

Open Energy Info (EERE)

Resonant Chambers MRC 1000 Resonant Chambers MRC 1000 < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Multi Resonant Chambers MRC 1000.jpg Technology Profile Primary Organization ORECon Technology Resource Click here Wave Technology Type Click here Oscillating Water Column Technology Readiness Level Click here TRL 5 6 System Integration and Technology Laboratory Demonstration Technology Description A 1 5MW Multi Resonant Chamber MRC using Oscillating Water Column OWC principles Consists of 3 x 500kW independent chambers each with a Dresser Rand HydroAir turbine driving an induction generator Full power conversion system delivers grid compliant power 1 5MW 33kV 60Hz to shore Device is tension moored to maximise power capture and minimise footprint All maintenance is done on board No moving parts in the water Turbines are low speed 300rpm high efficiency 75 and low noise

283

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

SciTech Connect

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

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

2010-12-07T23:59:59.000Z

284

Laboratory Measurements of Axial Pressures in Two-Celled Tornado-like Vortices  

Science Conference Proceedings (OSTI)

An experimental study of two-celled vortex flows was conducted in a Ward-type tornado vortex chamber (TVC). Time-averaged, stream-static pressure measurements on the vortex axis and observations of the visualized flow in two-celled vortices are ...

Randal L. Pauley

1989-11-01T23:59:59.000Z

285

Nonlinear Control and Modeling of Rotating Stall in an Axial Flow Compressor  

E-Print Network (OSTI)

This thesis focuses on understanding the use of air injection as a means of controlling rotating stall in an axial flow compressor, involving modeling, dynamical systems analysis, and experimental investigations. The first step towards this understanding was the development of a low order model for air injection control, the starting point of which was the Moore and Greitzer model for axial flow compressors. The Moore and Greitzer model was extended to include the effects of air injection and bifurcation analysis was performed to determine how the closed loop system dynamics are different from those of the open loop system. This low order model was then used to determine the optimal placement of the air injection actuators. Experimental work focused on verifying that the low order model, developed for air injection actuation, qualitatively captured the behavior of the Caltech compressor rig. Open loop tests were performed to determine how the placement of the air injectors on the rig a...

Robert L. Behnken; Robert L. Behnken

1997-01-01T23:59:59.000Z

286

Plate Fin Heat Exchanger Model with Axial Conduction and Variable Properties  

E-Print Network (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 ...

Hansen, B J; Klebaner, A; 10.1063/1.4706971

2012-01-01T23:59:59.000Z

287

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

SciTech Connect

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

288

Electrophoretic Migration and Axial Diffusion of Individual Nanoparticles in Cylindrical Nanopores  

SciTech Connect

Membranes with straight, vertical nanopores have found widespread applications in chemical and biological sciences, including separation, detection, catalysis, and drug delivery. They can also serve as a model system to understand molecular behavior and fundamental mechanisms of separation, bridging the gap between conventional model systems such as flat surfaces and real chromatographic stationary phases such as micrometer-sized porous particles. We recently found that the axial motion of individual biomolecules inside nanopores can be significantly slower than in bulk solution. This suggests that either chromatographic adsorption was present and/or the viscosity inside the nanopores was unusually high. In this study, we measured the electrophoretic motion as well as the axial diffusion of individual nanoparticles in cylindrical alumina nanopores. We found that the electrophoretic mobilities and the diffusion coefficients of polystyrene nanoparticles were both substantially smaller compared to bulk solution independent of particle size or pore diameter. The results imply that the apparent solution viscosity in nanodomains is anomalous.

Han, Rui; Wang, Gufeng; Qi, Shengda; Ma, Changbei; Yeung, Edward S.

2012-08-01T23:59:59.000Z

289

Axial Flux, Modular, Permanent-Magnet Generator with a Toroidal Winding for Wind Turbine Applications  

NLE Websites -- All DOE Office Websites (Extended Search)

CP-500-24996 Ÿ UC Category: 1213 CP-500-24996 Ÿ UC Category: 1213 Axial Flux, Modular, Permanent- Magnet Generator with a Toroidal Winding for Wind Turbine Applications E. Muljadi C.P. Butterfield Yih-Huei Wan National Wind Technology Center National Renewable Energy Laboratory Presented at IEEE Industry Applications Conference St. Louis, MO November 5-8, 1998 National Renewable Energy Laboratory 1617 Cole Boulevard

290

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

SciTech Connect

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

Wang, Y.-M.; Sheeley, N. R. Jr. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Stenborg, G., E-mail: yi.wang@nrl.navy.mil, E-mail: neil.sheeley@nrl.navy.mil, E-mail: guillermo.stenborg.ctr.ar@nrl.navy.mil [George Mason University, Fairfax, VA 22030 (United States)

2013-06-10T23:59:59.000Z

291

EPRI Phased Array Performance Demonstration for Axial Entry Blade Attachment Inspection - Technical Update  

Science Conference Proceedings (OSTI)

The disk rim blade attachment area is one of the most highly stressed components of the steam turbine rotor. Reliable and accurate inspection of the disk rim blade attachment area is essential for the determination of rotor operability and remaining life. The purpose of the Electric Power Research Institute's (EPRI's) Phased Array Performance Demonstration for Axial Entry Blade Attachment Inspection Project is to determine the inspection performance levels of commercial entities offering these inspection...

2008-12-22T23:59:59.000Z

292

Behaviour of GFRP Adhesive Pipe Joints Subjected to Pressure and Axial Loadings  

E-Print Network (OSTI)

represent an attractive alternative for pipelines subjected to severe internal or external environments in onshore or offshore applications. One important issue in the design of GFRP pipe systems is the material anisotropy, which poses certain... properties, the fibre volume fraction and the winding angle. For pipe applications, 55 (with respect to the axial direction) fibre winding angles are commonly used. A further aspect in the design of any advanced composite system is the joint detail...

Lees, J. M.

2005-07-05T23:59:59.000Z

293

Experimental Verification of the Root Cause Mechanism for Axial Offset Anomaly  

Science Conference Proceedings (OSTI)

Researchers at the Georgia Institute of Technology built a test facility designed to experimentally verify the root cause mechanism for axial offset anomaly (AOA) in pressurized water reactors (PWRs). Tests consisted of depositing materials from the simulated PWR coolant on zircaloy-4 test elements, followed by rapid isolation from the boron-rich coolant to trap within the deposit layer any boron compounds having retrograde solubility. Although significant amounts of boron (up to 8 weight percent) were i...

2002-12-03T23:59:59.000Z

294

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

SciTech Connect

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

295

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

296

Collimation of a Circulating Beam in the U_70 Synchrotron by Use of Reflections in Axially - Oriented Crystals  

E-Print Network (OSTI)

The possibilities of the extraction and collimation of a circulating beam by a new method due to the reflection of particles in crystals with axial orientation were experimentally investigated in the Fall-2010 run at the U_70 synchrotron. Such crystals have positive features, because the axial potential is five times larger than the planar potential. It has been shown that the collimation efficiency can reach 90% due to axial effects in the crystal. Losses of the circulating beam on a collimator have been reduced by several times; this makes it possible to suppress the muon jet near the steel collimator of the circulating beam.

Afonin, A G; Bulgakov, M K; Voinov, I S; Gorlov, V N; Ivanova, I V; Krylov, D M; Lunn'kov, A N; Maisheev, V A; Reshetnikov, S F; Savin, D A; Syshchikov, E A; Terekhov, V I; Chesnokov, Yu A; Chirkov, P N; Yazynin, I A

2011-01-01T23:59:59.000Z

297

Characterization of a multi-axis ion chamber array  

Science Conference Proceedings (OSTI)

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

Simon, Thomas A.; Kozelka, Jakub; Simon, William E.; Kahler, Darren; Li, Jonathan; Liu, Chihray [Department of Nuclear and Radiological Engineering, University of Florida, 202 Nuclear Science Building, Gainesville, Florida 32611-8300 (United States); Department of Radiation Oncology, Health Science Center, University of Florida, P.O. Box 100385, Gainesville, Florida 32610-0385 (United States) and Sun Nuclear Corporation, 425-A Pineda Court, Melbourne, Florida 32940 (United States); Sun Nuclear Corporation, 425-A Pineda Court, Melbourne, Florida 32940 (United States); Department of Radiation Oncology, Health Science Center, University of Florida, P.O. Box 100385, Gainesville, Florida 32610-0385 (United States)

2010-11-15T23:59:59.000Z

298

Resistive wall heating due to image current on the beam chamber for a superconducting undulator.  

SciTech Connect

The image-current heating on the resistive beam chamber of a superconducting undulator (SCU) was calculated based on the normal and anomalous skin effects. Using the bulk resistivity of copper for the beam chamber, the heat loads were calculated for the residual resistivity ratios (RRRs) of unity at room temperature to 100 K at a cryogenic temperature as the reference. Then, using the resistivity of the specific aluminum alloy 6053-T5, which will be used for the SCU beam chamber, the heat loads were calculated. An electron beam stored in a storage ring induces an image current on the inner conducting wall, mainly within a skin depth, of the beam chamber. The image current, with opposite charge to the electron beam, travels along the chamber wall in the same direction as the electron beam. The average current in the storage ring consists of a number of bunches. When the pattern of the bunched beam is repeated according to the rf frequency, the beam current may be expressed in terms of a Fourier series. The time structure of the image current is assumed to be the same as that of the beam current. For a given resistivity of the chamber inner wall, the application ofthe normal or anomalous skin effect will depend on the harmonic numbers of the Fourier series of the beam current and the temperature of the chamber. For a round beam chamber with a ratius r, much larger than the beam size, one can assume that the image current density as well as the density square, may be uniform around the perimeter 2{pi}r. For the SCU beam chamber, which has a relatively narrow vertical gap compared to the width, the effective perimeter was estimated since the heat load should be proportional to the inverse of the perimeter.

Kim, S. H. (Accelerator Systems Division (APS))

2012-03-27T23:59:59.000Z

299

Four-Button BPM Coefficients in Cylindrical and Elliptic Beam Chambers  

E-Print Network (OSTI)

Beam position monitor (BPM) coefficients are calculated from induced charges on four-button BPMs in circular and elliptic beam chambers for ?>> 1. Since the beam chamber cross-section for the APS storage ring is different from an exact elliptic geometry, numerical values of the BPM coefficients and their inversions are computed from two-dimensional electrostatic field distributions inside an exact geometry of the beam chamber. Utilizing Greens reciprocation theorem, a potential value is applied to the buttons rather than changing the beam position, and potential distributions corresponding to the beam positions are then computed. 1. Cylindrical Chamber A charged particle beam of short bunches induces charges on the beam chamber wall. Due to the Lorentz contraction, for ?>> 1, where ? is the relativistic factor, these charges have the same longitudinal intensity modulation as the beam. The electromagnetic fields associated with the beam are obtained by the Lorentz transformation from the fixed lab frame F to a moving reference frame F', where the charged beam is at rest [1, 2]. The field distribution inside the beam chamber becomes an electrostatic problem in the moving reference frame. Here we assume that the buttons are installed flush with the inner surface of the beam chamber, with the chamber having constant crosssection and the chamber wall at a uniform potential. For the charge density of a filament beam located at (xo,yo) in the transverse plane of the Cartesian coordinates and moving with a wave number k in the longitudinal direction z in the lab frame F, ? = ? ( x, y) cos k( z ? vt); (1) k

S. H. Kim

1999-01-01T23:59:59.000Z

300

Four-button BPM coefficients in cylindrical and elliptic beam chambers.  

Science Conference Proceedings (OSTI)

Beam position monitor (BPM) coefficients are calculated from induced charges on four-button BPMs in circular and elliptic beam chambers for {gamma} >>1. Since the beam chamber cross-section for the APS storage ring is different from an exact elliptic geometry, numerical values of the BPM coefficients and their inversions are computed from two-dimensional electrostatic field distributions inside an exact geometry of the beam chamber. Utilizing Green's reciprocation theorem, a potential value is applied to the buttons rather than changing the beam position, and potential distributions corresponding to the beam positions are then computed.

Kim, S.H.

1999-04-08T23:59:59.000Z

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.


301

Enclosed Chambers for Humidity Control And Sample Containment in Fiber Diffraction  

Science Conference Proceedings (OSTI)

A chamber and stretch frame for making fibers for diffraction is described. The chamber is made from a simple plastic cuvette with silicon nitride windows. It is suitable for maintaining constant humidity during fiber drying and data collection, and allows stretching of the fiber and exposure to magnetic fields during sample preparation. If necessary, it provides primary containment for toxic and infectious biological materials. The chamber has been used in fiber diffraction experiments with filamentous plant viruses and a yeast prion protein, and is shown to produce excellent orientation and to maintain hydration and order at the molecular level.

McDonald, M.; Kendall, A.; Tanaka, M.; Weissman, J.S.; Stubbs, G.

2009-05-26T23:59:59.000Z

302

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

DOE R&D Accomplishments (OSTI)

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

Charpak, G.; Sauli, F.

1973-02-14T23:59:59.000Z

303

Axial, induced pseudoscalar, and pion-nucleon form factors in manifestly Lorentz-invariant chiral perturbation theory  

Science Conference Proceedings (OSTI)

We calculate the nucleon form factors G{sub A} and G{sub P} of the isovector axial-vector current and the pion-nucleon form factor G{sub {pi}}{sub N} in manifestly Lorentz-invariant baryon chiral perturbation theory up to and including order O(p{sup 4}). In addition to the standard treatment including the nucleon and pions, we also consider the axial-vector meson a{sub 1} as an explicit degree of freedom. This is achieved by using the reformulated infrared renormalization scheme. We find that the inclusion of the axial-vector meson effectively results in one additional low-energy coupling constant that we determine by a fit to the data for G{sub A}. The inclusion of the axial-vector meson results in an improved description of the experimental data for G{sub A}, while the contribution to G{sub P} is small.

Schindler, M. R.; Fuchs, T.; Scherer, S. [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany); Gegelia, J. [Institut fuer Kernphysik, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany); High Energy Physics Institute, Tbilisi State University, Tbilisi, Georgia (United States)

2007-02-15T23:59:59.000Z

304

Prospecting for Hydrothermal Vents Using Moored Current and Temperature Data: Axial Volcano on the Juan de Fuca Ridge, Northeast Pacific  

Science Conference Proceedings (OSTI)

Tidal and inertial currents and profuse hydrothermal discharge at recently erupted Axial Volcano, Juan de Fuca Ridge, cause relatively large and rapid temperature (T) changes in the near-bottom water column. Measurements show short-term T ...

J. W. Lavelle; M. A. Wetzler; E. T. Baker; R. W. Embley

2001-03-01T23:59:59.000Z

305

On the property of measurements with the PTW microLion chamber in continuous beams  

Science Conference Proceedings (OSTI)

Purpose: The performance of liquid ionization chambers, which may prove to be useful tools in the field of radiation dosimetry, is based on several chamber and liquid specific characteristics. The present work investigates the performance of the PTW microLion liquid ionization chamber with respect to recombination losses and perturbations from ambient electric fields at various dose rates in continuous beams. Methods: In the investigation, experiments were performed using two microLion chambers, containing isooctane (C{sub 8}H{sub 18}) and tetramethylsilane [Si(CH{sub 3}){sub 4}] as the sensitive media, and a NACP-02 monitor chamber. An initial activity of approximately 250 GBq {sup 18}F was employed as the radiation source in the experiments. The initial dose rate in each measurement series was estimated to 1.0 Gy min{sup -1} by Monte Carlo simulations and the measurements were carried out during the decay of the radioactive source. In the investigation of general recombination losses, employing the two-dose-rate method for continuous beams, the liquid ionization chambers were operated at polarizing voltages 25, 50, 100, 150, 200, and 300 V. Furthermore, measurements were also performed at 500 V polarizing voltage in the investigation of the sensitivity of the microLion chamber to ambient electric fields. Results: The measurement results from the liquid ionization chambers, corrected for general recombination losses according to the two-dose-rate method for continuous beams, had a good agreement with the signal to dose linearity from the NACP-02 monitor chamber for general collection efficiencies above 70%. The results also displayed an agreement with the theoretical collection efficiencies according to the Greening theory, except for the liquid ionization chamber containing isooctane operated at 25 V. At lower dose rates, perturbations from ambient electric fields were found in the microLion chamber measurement results. Due to the perturbations, measurement results below an estimated dose rate of 0.2 Gy min{sup -1} were excluded from the present investigation of the general collection efficiency. The perturbations were found to be more pronounced when the chamber polarizing voltage was increased. Conclusions: By using the two-dose-rate method for continuous beams, comparable corrected ionization currents from experiments in low and medium energy photon beams can be achieved. However, the valid range of general collection efficiencies has been found to vary in a comparison between experiments performed in continuous beams of 120 kVp x ray, and the present investigation of 511 keV annihilation photons. At very high dose rates in continuous beams, there are presently no methods that can be used to correct for general recombination losses and at low dose rates the microLion chamber may be perturbed by ambient electric fields. Increasing the chamber polarizing voltage, which diminishes the general recombination effect, was found to increase the microLion chamber sensitivity to ambient electric fields. Prudence is thus advised when employing the microLion chamber in radiation dosimetry, as ambient electric fields of the strength observed in the present work may be found in many common situations. Due to uncertainties in the theoretical basis for recombination losses in liquids, further studies on the underlying theories for the initial and general recombination effect are needed if liquid ionization chambers are to become a viable option in high precision radiation dosimetry.

Andersson, Jonas; Johansson, Erik; Toelli, Heikki [Department of Radiation Sciences, Radiation Physics, Umea University, SE-901 85 Umea (Sweden); Swedish Defense Research Agency, FOI CBRN Defense and Security, SE-901 82 Umea (Sweden); Department of Radiation Sciences, Radiation Physics, Umea University, SE-901 85 Umea (Sweden)

2012-08-15T23:59:59.000Z

306

Neutron And Gamma Detector Using An Ionization Chamber With An Integrated  

NLE Websites -- All DOE Office Websites (Extended Search)

Neutron And Gamma Detector Using An Ionization Chamber Neutron And Gamma Detector Using An Ionization Chamber Neutron And Gamma Detector Using An Ionization Chamber With An Integrated Body And Moderator A detector for detecting neutrons and gamma radiation includes a cathode that defines an interior surface and an interior volume. Available for thumbnail of Feynman Center (505) 665-9090 Email Neutron And Gamma Detector Using An Ionization Chamber With An Integrated Body And Moderator 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

307

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

308

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

309

A Rapid-Circulation Evaporation Chamber for Measuring Bulk Stomatal Resistance  

Science Conference Proceedings (OSTI)

A relatively simple method is described for determining evaporation of short vegetation at any moment of time. The method is based on the measurement of bulk stomatal resistance of the crop with an evaporation chamber. Once this quantity is known,...

W. Kohsiek

1981-01-01T23:59:59.000Z

310

Condensation Coefficient Measurement for Water in the UMR Cloud Simulation Chamber  

Science Conference Proceedings (OSTI)

A systematic series of condensation coefficient measurements of water have been made using the University of MissouriRolla cooled-wall expansion chamber which simulates the thermodynamics of cloud. This coefficient is seen to decrease from a ...

D. E. Hagen; J. Schmitt; M. Trueblood; J. Carstens; D. R. White; D. J. Alofs

1989-03-01T23:59:59.000Z

311

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

312

Space Chamber Reaches Cold Target at Unprecedented Efficiency | U.S. DOE  

NLE Websites -- All DOE Office Websites (Extended Search)

Space Chamber Reaches Cold Target at Unprecedented Efficiency Space Chamber Reaches Cold Target at Unprecedented Efficiency Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Funding Opportunities Nuclear Science Advisory Committee (NSAC) News & Resources Contact Information Nuclear Physics U.S. Department of Energy SC-26/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3613 F: (301) 903-3833 E: sc.np@science.doe.gov More Information » October 2012 Space Chamber Reaches Cold Target at Unprecedented Efficiency Thomas Jefferson Laboratory lends expertise in cryogenics developments. Print Text Size: A A A Subscribe FeedbackShare Page Click to enlarge photo. Enlarge Photo Image courtesy of NASA NASA's Space Environment Simulation Lab Chamber A, which is used by the

313

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

SciTech Connect

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.

2013-08-01T23:59:59.000Z

314

Dual-chamber plasma deposition of A-Si:H solar cells at high rates using disilane  

SciTech Connect

The use of a separated chamber deposition system for the fabrication of a-Si:H solar cells from disilane at high deposition rates results in a substantial improvement in short circuit current compared to that obtained from a single-chamber system. The spectral responses of cells fabricated in the dual-chamber mode are compared to those made in the single-chamber mode. The results are interpreted by assuming that the rate of removal of boron contaminants from the chamber is independent of deposition rate.

Rajeswaran, G.; Vanier, P.E.; Corderman, R.R.; Kampas, F.J.

1985-01-01T23:59:59.000Z

315

Axial force imparted by a conical radiofrequency magneto-plasma thruster  

SciTech Connect

Direct thrust measurements of a low pressure ({approx}0.133 Pa) conical radiofrequency (rf at 13.56 MHz) argon plasma source show a total axial force of about 5 mN for an effective rf power of 650 W and a maximum magnetic field of 0.018 T, of which a measured value of 2.5 mN is imparted by the magnetic nozzle. A simplified model of thrust including contributions from the electron pressure and from the magnetic field pressure is developed. The magnetic nozzle is modelled as a ''physical'' nozzle of increasing cross-sectional area.

Charles, C.; Takahashi, K.; Boswell, R. W. [Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, Australian National University, ACT 0200 (Australia)

2012-03-12T23:59:59.000Z

316

Axial thermal medium delivery tubes and retention plates for a gas turbine rotor  

SciTech Connect

In a multi-stage turbine rotor, tubes are disposed in openings adjacent the rotor rim for flowing a thermal medium to rotor buckets and returning spent thermal medium. The tubes have axially spaced lands of predetermined wall thickness with thin-walled tube sections between the lands and of increasing thickness from the forward to the aft ends of the tubes. A pair of retention plates are carried on the aft end face of the aft wheel and straddle the tube and engage against a shoulder on the tube to preclude displacement of the tube in an aft direction.

Mashey, Thomas Charles (Coxsackie, NY)

2002-01-01T23:59:59.000Z

317

Measurement of velocity deficit at the downstream of a 1:10 axial hydrokinetic turbine model  

DOE Green Energy (OSTI)

Wake recovery constrains the downstream spacing and density of turbines that can be deployed in turbine farms and limits the amount of energy that can be produced at a hydrokinetic energy site. This study investigates the wake recovery at the downstream of a 1:10 axial flow turbine model using a pulse-to-pulse coherent Acoustic Doppler Profiler (ADP). In addition, turbine inflow and outflow velocities were measured for calculating the thrust on the turbine. The result shows that the depth-averaged longitudinal velocity recovers to 97% of the inflow velocity at 35 turbine diameter (D) downstream of the turbine.

Gunawan, Budi [ORNL; Neary, Vincent S [ORNL; Hill, Craig [St. Anthony Falls Laboratory, 2 Third Avenue SE, Minneapolis, MN 55414; Chamorro, Leonardo [St. Anthony Falls Laboratory, 2 Third Avenue SE, Minneapolis, MN 55414

2012-01-01T23:59:59.000Z

318

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

319

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

2010-07-22T23:59:59.000Z

320

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

Science Conference Proceedings (OSTI)

A precise measurement of the neutron decay {beta} asymmetry A{sub 0} has been carried out using polarized ultracold neutrons from the pulsed spallation ultracold neutron source at the Los Alamos Neutron Science Center. Combining data obtained in 2008 and 2009, we report A{sub 0}=-0.119 66{+-}0.000 89{sub -0.00140}{sup +0.00123}, from which we determine the ratio of the axial-vector to vector weak coupling of the nucleon g{sub A}/g{sub V}=-1.275 90{sub -0.00445}{sup +0.00409}.

Liu, J. [Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, California 91125 (United States); Department of Physics, Shanghai Jiao Tong University, Shanghai, 200240 (China); Mendenhall, M. P.; Carr, R.; Filippone, B. W.; Hickerson, K. P.; Perez Galvan, A.; Russell, R. [Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, California 91125 (United States); Holley, A. T.; Hoagland, J.; VornDick, B. [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States); Back, H. O.; Pattie, R. W. Jr.; Young, A. R. [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States); Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708 (United States); Bowles, T. J.; Clayton, S.; Currie, S.; Hogan, G. E.; Ito, T. M.; Makela, M.; Morris, C. L. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2010-10-29T23:59:59.000Z

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321

Directional Detection of Fast Neutrons Using a Time Projection Chamber  

Science Conference Proceedings (OSTI)

Spontaneous fission in Special Nuclear Material (SNM) such as plutonium and highly enriched uranium (HEU) results in the emission of neutrons with energies in the MeV range (hereafter 'fast neutrons'). These fast neutrons are largely unaffected by the few centimeters of intervening high-Z material that would suffice for attenuating most emitted gamma rays, while tens of centimeters of hydrogenous materials are required to achieve substantial attenuation of neutron fluxes from SNM. Neutron detectors are therefore an important complement to gamma-ray detectors in SNM search and monitoring applications. The rate at which SNM emits fast neutrons varies from about 2 per kilogram per second for typical HEU to some 60,000 per kilogram per second for metallic weapons grade plutonium. These rates can be compared with typical sea-level (cosmogenic) neutron backgrounds of roughly 5 per second per square meter per steradian in the relevant energy range [1]. The fact that the backgrounds are largely isotropic makes directional neutron detection especially attractive for SNM detection. The ability to detect, localize, and ultimately identify fast neutron sources at standoff will ultimately be limited by this background rate. Fast neutrons are particularly well suited to standoff detection and localization of SNM or other fast neutrons sources. Fast neutrons have attenuation lengths of about 60 meters in air, and retain considerable information about their source direction even after one or two scatters. Knowledge of the incoming direction of a fast neutron, from SNM or otherwise, has the potential to significantly improve signal to background in a variety of applications, since the background arriving from any one direction is a small fraction of the total background. Imaging or directional information therefore allows for source detection at a larger standoff distance or with shorter dwell times compared to nondirectional detectors, provided high detection efficiency can be maintained. Directional detection of neutrons has been previously considered for applications such as controlled fusion neutron imaging [2], nuclear fuel safety research [3], imaging of solar neutrons and SNM [4], and in nuclear science [5]. The use of scintillating crystals and fibers has been proposed for directional neutron detection [6]. Recently, a neutron scatter camera has been designed, constructed, and tested for imaging of fast neutrons, characteristic for SNM material fission [7]. The neutron scatter camera relies on the measurement of the proton recoil angle and proton energy by time of flight between two segmented solid-state detectors. A single-measurement result from the neutron scatter camera is a ring containing the possible incident neutron direction. Here we describe the development and commissioning of a directional neutron detection system based on a time projection chamber (TPC) detector. The TPC, which has been widely used in particle and nuclear physics research for several decades, provides a convenient means of measuring the full 3D trajectory, specific ionization (i.e particle type) and energy of charged particles. For this application, we observe recoil protons produced by fast neutron scatters on protons in hydrogen or methane gas. Gas pressures of a few ATM provide reasonable neutron interaction/scattering rates.

Bowden, N; Heffner, M; Carosi, G; Carter, D; Foxe, M; Jovanovic, I

2009-06-03T23:59:59.000Z

322

Tests of a two-stage, axial-flow, two-phase turbine  

SciTech Connect

A two-phase-flow turbine with two stages of axial-flow impulse rotors was tested with three different working-fluid mixtures at a shaft power of 30 kW. The turbine efficiency was 0.55 with nitrogen-and-water of 0.02 quality and 94 m/s velocity, 0.57 with Refrigerant 22 of 0.27 quality and 123 m/s velocity, and 0.30 with steam-and-water of 0.27 quality and 457 m/s velocity. The efficiencies with nitrogen-and-water and Refrigerant 22 were 86% of theoretical. At that fraction of theoretical, the efficiencies of optimized two-phase turbines would be in the low 60% range with organic working fluids and in the mid 50% range with steam-and-water. The recommended turbine design is a two-stage axial-flow impulse turbine followed by a rotary separator for discharge of separate liquid and gas streams and recovery of liquid pressure.

Elliott, D.G.

1982-12-15T23:59:59.000Z

323

Analysis of the thorium axial blanket experiments in the proteus reactor  

SciTech Connect

Detailed analysis has been completed for the ThO/sub 2/ and Th-metal axial blanket experiments performed at the Swiss PROTEUS critical facility in order to compare reaction rates and neutron spectra measured in prototypic GCFR configurations with calculated results. The PROTEUS configurations allowed the analysis of infinitely dilute thorium data in a PuO/sub 2//UO/sub 2/ fast lattice spectrum at core center as well as the analysis of resonance self-shielding effects in the thorium-bearing axial blankets. These comparisons indicate that significant deficiencies still exist in the latest evaluated infinitely dilute thorium data file. Specifically, the analysis showed that the /sup 232/Th capture is underpredicted by ENDF/B-IV data, and the discrepancies are further exaggerated by ENDF/B-V data. On the other hand, ENDF/B-V /sup 232/Th fission data appear to be significantly improved relative to ENDF/B-IV data, while discrepancies are extremely large for the (n,2n) process in both data files. Finally, the (n,n') cross sections for thorium also appear improved in ENDF/B-V, except for a small energy range just above the 50 keV threshold. Therefore, these combined data deficiencies suggest that relatively large uncertainties should be associated with many of the results obtained from recent fast reactor alternate fuel cycle analyses. 38 figures, 12 tables.

White, J.R.; Ingersoll, D.T.

1980-12-01T23:59:59.000Z

324

Analysis Of Residence Time Distribution Of Fluid Flow By Axial Dispersion Model  

Science Conference Proceedings (OSTI)

Radioactive tracer {sup 82}Br in the form of KBr-82 with activity {+-} 1 mCi has been injected into steel pipeline to qualify the extent dispersion of water flowing inside it. Internal diameter of the pipe is 3 in. The water source was originated from water tank through which the water flow gravitically into the pipeline. Two collimated sodium iodide detectors were used in this experiment each of which was placed on the top of the pipeline at the distance of 8 and 11 m from injection point respectively. Residence time distribution (RTD) curves obtained from injection of tracer are elaborated numerically to find information of the fluid flow properties. The transit time of tracer calculated from the mean residence time (MRT) of each RTD curves is 14.9 s, therefore the flow velocity of the water is 0.2 m/s. The dispersion number, D/uL, for each RTD curve estimated by using axial dispersion model are 0.055 and 0.06 respectively. These calculations are performed after fitting the simulated axial dispersion model on the experiment curves. These results indicated that the extent of dispersion of water flowing in the pipeline is in the category of intermediate.

Sugiharto [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia); Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Su'ud, Zaki; Kurniadi, Rizal; Waris, Abdul [Centre for Applications of Isotopes and Radiation Technology-National Nuclear Energy Agency, Jl. Lebak Bulus Raya No. 49, Jakarta 12440 (Indonesia); Abidin, Zainal [Department of Physics, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung 40132 (Indonesia)

2010-12-23T23:59:59.000Z

325

Effects of axial heat conduction and material properties on the performance characteristics of a thermal transient anemometer probe  

Science Conference Proceedings (OSTI)

This paper describes an investigation of the axial heat transfer within a thermal transient anemometer probe. A previous study, evaluated the performance characteristics of a thermal transient anemometer system. The study revealed discrepancies between a simplified theory and test results in the development of a universal calibration curve for probes of varying diameters. Although the cause of these discrepancies were left uncertain due to an inadequate theoretical model, the study suggested that axial conduction within the probe could account for the deviations. In this paper, computer simulations are used to further investigate axial heat conduction within the probes. The effect on calibration of axial variations of material properties along the probes is also discussed. Results from the computer simulation are used in lieu of the theoretical model used in the previous study to develop a satisfactory universal calibration curve. The computer simulations provide evidence that there is significant axial heat conduction within the probes, and that this was the cause of the discrepancies noted in the previous study.

Bailey, J.L.; Page, R.J. [Argonne National Lab., IL (United States); Acharya, M. [Illinois Inst. of Technology, Chicago, IL (United States). Fluid Dynamics Research Center

1995-07-01T23:59:59.000Z

326

Interaction of a rotational motion and an axial flow in small geometries for a Couette-Taylor problem  

E-Print Network (OSTI)

We analyze the stability of a cylindrical Couette flow under the imposition of a weak axial flow in case of a very short cylinder with a narrow annulus gap. We consider an incompressible viscous fluid which is contained in the narrow gap between two concentric short cylinders, where the inner cylinder rotates with constant angular velocity. The caps of the cylinders have narrow tubes conically tapering to super narrow slits which allow for an axial flow along the surface of the inner cylinder. The approximated solution for the Couette flow for short cylinders was found and used for the stability analysis instead of the exact but bulky solution. The sensitivity of the Couette flow to general small perturbations and to the weak axial flow was studied. We demonstrate that perturbations coming from the axial flow cause the propagation of dispersive waves in the Taylor-Couette flow. The coexistence of a rotation and of an axial flow requires to study in addition to the energy and the angular momentum also the heli...

Bordag, L A; Froehner, M; Myrnyy, V

2003-01-01T23:59:59.000Z

327

Photon stimulated desorption measurement of an extruded aluminum beam chamber for the Advanced Photon Source  

DOE Green Energy (OSTI)

The Advanced Photon Source (APS), presently being commisioned, will produce X-ray s of unprecedented brightness. The high energy ring of the APS is a 7 GeV positron storage ring, 1104 meters in circumference designed to operate at less than 10{sup {minus}9} Torr with 300 ma of beam and a greater than 10 hour lifetime. The storage ring vacuum chamber is constructed from an extruded 6063 aluminum alloy. During the construction phase, a 2.34 m long section of the APS extruded aluminum chamber was set up on National Synchrotron Light Source (NSLS) X-ray Beamlline X28A and Photon Stimulated Desorption (PSD) was measured. Cleaning and preparation of the chamber was identical to that of the APS construction. In addition to the chamber, small samples of M, Be, and Cu were also exposed to white light having a critical energy of 5 keV. In addition to PSD, measurements were made of specular and diffuse scattering of photons. The chamber and samples were each exposed to a dose greater than 10{sup 23} photons per meter. Desorption yields for H{sub 2}, CO, CO{sub 2}, CH{sub 4} and H{sub 2}0 are reported as a function of accumulated flux, critical energy, incidence angle, and preparation. These results are compared with previous results for aluminum on NSLS Beamlline U1OB and PSD results of other laboratories published for aluminum.

Foerster, C.L.; Lanni, C. [Brookhaven National Lab., Upton, NY (United States); Noonan, J.R.; Rosenberg, R.A. [Argonne National Lab., IL (United States)

1995-12-31T23:59:59.000Z

328

Vacuum chamber of the injector synchrotron for the Advanced Photon Source  

Science Conference Proceedings (OSTI)

The 40 chambers of the 368 m, 7-GeV injector synchrotron of the Advanced Photon Source are made from 1 mm-thick, 316LN stainless steel tubing. Tubes are cold-drawn to an elliptical shape with inside major and minor axes of 6 cm and 3.7 cm, respectively. This results in a thin metallic chamber without corrugations, which allows maximum beam space in the magnets and withstands atmospheric pressure. Sections of the chamber are bent to match the radius of curvature (33.3 m) of the beam over the entire effective length of the dipole magnets. A modified orbital welder is used to join sections of tubing. The chambers and the pumping system required to achieve a pressure of 10{sup {minus}9} Torr are described. A straight section of chamber tubing was tested under external pressure up to 60 psig. At 15 psig, the resulting deflection at the minor half axis was 0.2mm and a maximum compressive stress of 13,500 psi was measured. Tube deformation remained in the elastic region up to {approximately}38 psig. 4 refs., 2 figs.

Benaroya, R.; Dortwegt, R.

1991-01-01T23:59:59.000Z

329

Single Particle Laser Mass Spectrometry Applied to Differential Ice Nucleation Experiments at the AIDA Chamber  

SciTech Connect

Experiments conducted at the Aerosol Interactions and Dynamics in the Atmosphere (AIDA) chamber located in Karlsruhe, Germany permit investigation of particle properties that affect the nucleation of ice at temperature and water vapor conditions relevant to cloud microphysics and climate issues. Ice clouds were generated by heterogeneous nucleation of Arizona test dust (ATD), illite, and hematite and homogeneous nucleation of sulfuric acid. Ice crystals formed in the chamber were inertially separated from unactivated, or interstitial aerosol particles with a pumped counterflow virtual impactor (PCVI), then evaporated. The ice residue (i.e., the aerosol which initiated ice nucleation plus any material which was scavenged from the gas- and/or particle-phase), was chemically characterized at the single particle level using a laser ionization mass spectrometer. In this manner the species that first nucleated ice could be identified out of a mixed aerosol population in the chamber. Bare mineral dust particles were more effective ice nuclei (IN) than similar particles with a coating. Metallic particles from contamination in the chamber initiated ice nucleation before other species but there were few enough that they did not compromise the experiments. Nitrate, sulfate, and organics were often detected on particles and ice residue, evidently from scavenging of trace gas-phase species in the chamber. Hematite was a more effective ice nucleus than illite. Ice residue was frequently larger than unactivated test aerosol due to the formation of aggregates due to scavenging, condensation of contaminant gases, and the predominance of larger aerosol in nucleation.

Gallavardin, S. J.; Froyd, Karl D.; Lohmann, U.; Moehler, Ottmar; Murphy, Daniel M.; Cziczo, Dan

2008-08-26T23:59:59.000Z

330

Plate Fin Heat Exchanger Model with Axial Conduction and Variable Properties  

Science Conference Proceedings (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

331

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

SciTech Connect

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

332

Axial force imparted by a current-free magnetically expanding plasma  

SciTech Connect

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

333

An Axial Dispersion Model for Gas - Liquid Reactors Based on the Penetration Theory  

E-Print Network (OSTI)

An axial dispersion reactor model for gas -- liquid reaction systems is proposed in this paper based on the penetration theory. The mass transfer mechanism accompanied by a chemical irreversible first-order reaction is mathematically treated in a new way in order to use its results to develop the model conveniently. Analytical solutions can be obtained for the equation system involving linear differential equations by using of the eigenvalues of the equation system. In addition, an iteration procedure is given to solve the nonlinear differential equation system numerically. The influences of the important model parameters on the concentration profile, the mass transfer and the reactant conversion are also studied. 1997 Elsevier Science S.A.

Jinfu Wang; Shejiao Han; Fei Wei; Zhiqing Yu; Yong Jin

1997-01-01T23:59:59.000Z

334

Computed axial tomography (CAT) contribution for dosimetry and treatment evaluation in lung cancer  

SciTech Connect

The use of computed axial tomography (CAT) scans in postoperative patients with lung cancer was studied to evaluate its contribution in dosimetry and to study the late effects of irradiation. Comparisons were made between the treatment planning generated from CAT scan data and that obtained from two orthogonal radiographs. Both methods offered a good approximation but with orthogonal radiographs possible mediastinal and lung shift could not be seen and the dose delivered to the spinal cord was overestimated. A control CAT scan performed 6 to 18 months after treatment showed a lung fibrosis that was strictly correlated with the treatment planning and related with doses and volume treated. CAT scans allowed more accurate treatment planning.

Van Houtte, P.; Piron, A.; Lustman-Marechal, J.; Osteaux, M.; Henry, J.

1980-08-01T23:59:59.000Z

335

Failure analysis of radioisotopic heat source capsules tested under multi-axial conditions  

DOE Green Energy (OSTI)

In order to qualify small radioisotopic heat sources for a 25-yr design life, multi-axial mechanical tests were performed on the structural components of the heat source. The results of these tests indicated that failure predominantly occurred in the middle of the weld ramp-down zone. Examination of the failure zone by standard metallographic techniques failed to indicate the true cause of failure. A modified technique utilizing chemical etching, scanning electron microscopy, and energy dispersive x-ray analysis was employed and dramatically indicated the true cause of failure, impurity concentration in the ramp-down zone. As a result of the initial investigation, weld parameters for the heat sources were altered. Example welds made with a pulse arc technique did not have this impurity buildup in the ramp-down zone.

Zielinski, R.E.; Stacy, E.; Burgan, C.E.

336

Constraining the Leading Weak Axial Two-body Current by SNO and Super-K  

E-Print Network (OSTI)

We analyze the Sudbury Neutrino Observatory (SNO) and Super-Kamiokande (SK) data on charged current (CC), neutral current (NC) and neutrino electron elastic scattering (ES) reactions to constrain the leading weak axial two-body current parameterized by L_1A. This two-body current is the dominant uncertainty of every low energy weak interaction deuteron breakup process, including SNO's CC and NC reactions. Our method shows that the theoretical inputs to SNO's determination of the CC and NC fluxes can be self-calibrated, be calibrated by SK, or be calibrated by reactor data. The only assumption made is that the total flux of active neutrinos has the standard ^8B spectral shape (but distortions in the electron neutrino spectrum are allowed). We show that SNO's conclusion about the inconsistency of the no-flavor-conversion hypothesis does not contain significant theoretical uncertainty, and we determine the magnitude of the active solar neutrino flux.

Jiunn-Wei Chen; Karsten M. Heeger; R. G. Hamish Robertson

2002-10-24T23:59:59.000Z

337

An imaging co-axial tube electrodynamic trap for manipulation of charged particles  

Science Conference Proceedings (OSTI)

A tubular particle trapping device was designed and fabricated using two co-axial electrically conductive tubes with diameters of 5 mm and 7 mm, respectively. The device was integrated with an imaging camera and optical fiber bundle for real time monitoring of trapped particle motion. Charged microparticles of 3 to 50 m diameter can be suspended in air at ambient pressure using the device utilizing a quadrupole potential with an alternating voltage of amplitude 300 V to 750 V and frequency of 30 Hz to 140 Hz. Controlled trapping of a single particle or multiple particles can be achieved by tuning the voltage amplitude. The particle remained trapped when the entire assembly was translated or rotated. The device can be used as a manipulator for charged particle transport and repositioning.

Jiang, Ms. Linan [University of Arizona; Whitten, William B [ORNL; Pau, Dr. Stanley [University of Arizona/Bell Labs

2011-01-01T23:59:59.000Z

338

New analytic solutions of the collective Bohr hamiltonian for a beta-soft, gamma-soft axial rotor  

E-Print Network (OSTI)

New analytic solutions of the quadrupole collective Bohr hamiltonian are proposed, exploiting an approximate separation of the beta and gamma variables to describe gamma-soft prolate axial rotors. The model potential is a sum of two terms: a beta-dependent term taken either with a Coulomb-like or a Kratzer-like form, and a gamma-dependent term taken as an harmonic oscillator. In particular it is possible to give a one parameter paradigm for a beta-soft, gamma-soft axial rotor that can be applied, with a considerable agreement, to the spectrum of 234U.

Lorenzo Fortunato; Andrea Vitturi

2003-12-18T23:59:59.000Z

339

Microwave electron cyclotron electron resonance (ECR) ion source with a large, uniformly distributed, axially symmetric, ECR plasma volume  

DOE Patents (OSTI)

An electron cyclotron resonance (ECR) ion source includes a primary mirror coil disposed coaxially around a vacuum vessel in which a plasma is induced and introducing a solenoidal ECR-producing field throughout the length of the vacuum vessel. Radial plasma confinement is provided by a multi-cusp, multi-polar permanent magnet array disposed azimuthally around the vessel and within the primary mirror coil. Axial confinement is provided either by multi-cusp permanent magnets at the opposite axial ends of the vessel, or by secondary mirror coils disposed on opposite sides of the primary coil.

Alton, Gerald D. (Kingston, TN)

1996-01-01T23:59:59.000Z

340

OSTIblog Posts by Kathy Chambers | OSTI, US Dept of Energy, Office of  

Office of Scientific and Technical Information (OSTI)

Kathy Chambers Kathy Chambers Kathy Chambers's picture Senior STI Specialist, Information International Associates, Inc. Enjoy the benefits of LED lighting Source: http://www.flickr.com/photos/uscapitol/6309229615/in/photostream/ Published on Dec 30, 2013 Every day we are bombarded with advertisements in every form and format telling us that our lives will be improved if we buy a particular product because it will save us money, reduce our work effort, save us energy, or benefit the environment. We are justifiably skeptical because we know from experience that if something sounds too good to be true, usually it is. Light-emitting diode (LED) lighting is one of the exceptions. LEDs benefits are so powerful that they seem too good to be true; however, they actually do save us money, reduce our work effort, save us energy and benefit our environment.

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

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Commerce Biofuels Dialogue Series: Outlook for an Commerce Biofuels Dialogue Series: Outlook for an Emerging Global Biofuels Market U.S. Chamber of Commerce Biofuels Dialogue Series: Outlook for an Emerging Global Biofuels Market January 29, 2008 - 10:53am Addthis Remarks as Prepared For Delivery by Secretary Bodman Thank you very much, Bruce, for that kind introduction. My thanks also to Tom Donahue and the leadership of the Chamber for inviting me to be with you today. I was quite pleased to hear that the Chamber was sponsoring this event. As anyone who knows me - or has heard me speak recently - can tell you, the biofuels industry is a favorite topic of mine. In my view, advanced biofuels offer tremendous promise for helping our nation to bring about a new energy future-one that is cleaner, more sustainable, more affordable,

342

Stability of A-150 plastic ionization chamber response over a ~30 year period  

SciTech Connect

At the NIU Institute for Neutron Therapy at Fermilab, the clinical tissue-equivalent ionization chamber response is measured every treatment day using a cesium source that was configured to match readings obtained at the National Bureau of Standards. Daily measurements are performed in air using the air-to-tissue dose conversion factors given in AAPM Report no. 7. The measured exposure calibration factors have been tabulated and graphed as a function of time from 1978 to present. For A-150 plastic ionization chambers, these factors exhibit a sinusoidal variation with a period of approximately one year and amplitude of {+-} 1%. This variation, attributable to the hygroscopic nature of A-150 plastic, is correlated with the relative humidity of the facility, and is greater than the humidity corrections for gas described in the literature. Our data suggest that chamber calibration should be performed at least weekly to accommodate these variations.

Kroc, Thomas K.; Lennox, Arlene J.; /Fermilab

2007-08-01T23:59:59.000Z

343

Selenide isotope generator for the Galileo Mission. Axially-grooved heat pipe: accelerated life test results  

SciTech Connect

The results through SIG/Galileo contract close-out of accelerated life testing performed from June 1978 to June 1979 on axially-grooved, copper/water heat pipes are presented. The primary objective of the test was to determine the expected lifetime of axially-grooved copper/water heat pipes. The heat pipe failure rate, due to either a leak or a build-up of non-condensible gas, was determined. The secondary objective of the test was to determine the effects of time and temperature on the thermal performance parameters relevant to long-term (> 50,000 h) operation on a space power generator. The results showed that the gas generation rate appears to be constant with time after an initial sharp rise although there are indications that it drops to approximately zero beyond approx. 2000 h. During the life test, the following pipe-hours were accumulated: 159,000 at 125/sup 0/C, 54,000 at 165/sup 0/C, 48,000 at 185/sup 0/C, and 8500 at 225/sup 0/C. Heated hours per pipe ranged from 1000 to 7500 with an average of 4720. Applying calculated acceleration factors yields the equivalent of 930,000 pipe-h at 125/sup 0/C. Including the accelerated hours on vendor tested pipes raises this number to 1,430,000 pipe-hours at 125/sup 0/C. It was concluded that, for a heat pipe temperature of 125/sup 0/C and a mission time of 50,000 h, the demonstrated heat pipe reliability is between 80% (based on 159,000 actual pipe-h at 125/sup 0/C) and 98% (based on 1,430,000 accelerated pipe-h at 125/sup 0/C). Measurements indicate some degradation of heat transfer with time, but no detectable degradation of heat transport. (LCL)

1979-08-01T23:59:59.000Z

344

Nonleptonic two-body B decays including axial-vector mesons in the final state  

SciTech Connect

We present a systematic study of exclusive charmless nonleptonic two-body B decays including axial-vector mesons in the final state. We calculate branching ratios of B{yields}PA, VA, and AA decays, where A, V, and P denote an axial vector, a vector, and a pseudoscalar meson, respectively. We assume a naive factorization hypothesis and use the improved version of the nonrelativistic Isgur-Scora-Grinstein-Wise quark model for form factors in B{yields}A transitions. We include contributions that arise from the effective {delta}B=1 weak Hamiltonian H{sub eff}. The respective factorized amplitudes of these decays are explicitly shown and their penguin contributions are classified. We find that decays B{sup -}{yields}a{sub 1}{sup 0}{pi}{sup -}, B{sup 0}{yields}a{sub 1}{sup {+-}}{pi}{sup {+-}}, B{sup -}{yields}a{sub 1}{sup -}K{sup 0}, B{sup 0}{yields}a{sub 1}{sup +}K{sup -}, B{sup 0}{yields}f{sub 1}K{sup 0}, B{sup -}{yields}f{sub 1}K{sup -}, B{sup -}{yields}K{sub 1}{sup -}(1400){eta}{sup (')}, B{sup -}{yields}b{sub 1}{sup -}K{sup 0}, and B{sup 0}{yields}b{sub 1}{sup +}{pi}{sup -}(K{sup -}) have branching ratios of the order of 10{sup -5}. We also study the dependence of branching ratios for B{yields}K{sub 1}P(V,A) decays [K{sub 1}=K{sub 1}(1270), K{sub 1}(1400)] with respect to the mixing angle between K{sub 1A} and K{sub 1B}.

Calderon, G.; Munoz, J. H.; Vera, C. E. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Coahuila, CP 27000, Torreon, Coahuila (Mexico); Departamento de Fisica, Universidad del Tolima, Apartado Aereo 546, Ibague (Colombia)

2007-11-01T23:59:59.000Z

345

Current scaling of axially radiated power in dynamic hohlraums and dynamic hohlraum load design for ZR.  

SciTech Connect

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

346

Small-Chamber Measurements of Chemical-Specific Emission Factors for  

NLE Websites -- All DOE Office Websites (Extended Search)

Small-Chamber Measurements of Chemical-Specific Emission Factors for Small-Chamber Measurements of Chemical-Specific Emission Factors for Drywall Title Small-Chamber Measurements of Chemical-Specific Emission Factors for Drywall Publication Type Report Year of Publication 2010 Authors Maddalena, Randy L., Marion L. Russell, Moya Melody, and Michael G. Apte Publisher Lawrence Berkeley National Laboratory City Berkeley Abstract Imported drywall installed in U.S. homes is suspected of being a source of odorous and potentially corrosive indoor pollutants. To support an investigation of those building materials by the Consumer Products Safety Commission (CPSC), Lawrence Berkeley National Laboratory (LBNL) measured chemical-specific emission factors for 30 samples of drywall materials. Emission factors are reported for 75 chemicals and 30 different drywall samples encompassing both domestic and imported stock and incorporating natural, synthetic, or mixed gypsum core material. CPSC supplied all drywall materials. First the drywall samples were isolated and conditioned in dedicated chambers, then they were transferred to small chambers where emission testing was performed. Four sampling and analysis methods were utilized to assess (1) volatile organic compounds, (2) low molecular weight carbonyls, (3) volatile sulfur compounds, and (4) reactive sulfur gases. LBNL developed a new method that combines the use of solid phase microextraction (SPME) with small emission chambers to measure the reactive sulfur gases, then extended that technique to measure the full suite of volatile sulfur compounds. The testing procedure and analysis methods are described in detail herein. Emission factors were measured under a single set of controlled environmental conditions. The results are compared graphically for each method and in detailed tables for use in estimating indoor exposure concentrations

347

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

DOE Green Energy (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

348

Investigation of long drift chambers for a nucleon-decay detector  

SciTech Connect

The use of long drift chambers for a nucleon-decay detector is discussed as a means of achieving a detector with very fine tracking, but with a modest number of readout channels. Strategies for reducing the attenuation of drifting electrons are considered, particularly the necessity of shaping the electric field to reduce the effects of diffusion and of nearby grounded conductors. Measured results are presented for a chamber with 1 cm drift gap and 50 cm maximum drift distance. The measured attenuation is 12%.

Price, L.E.; Dawson, J.; Ayres, D.; Denis, R.S.

1981-01-01T23:59:59.000Z

349

THE TREATMENT OF THE TRUMPET IN SELECTED JAZZ-INFLUENCED CLASSICAL CHAMBER WORKS OF THE TWENTIETH CENTURY.  

E-Print Network (OSTI)

??The trumpet has always maintained a central role in the jazz genre. However, throughout the history of chamber music the trumpet was overlooked until the (more)

Harrison, Kathleen Elizabeth

2009-01-01T23:59:59.000Z

350

Dynamics of neutralizing electrons during the focusing of intense heavy ions beams inside a heavy fusion reactor chamber  

E-Print Network (OSTI)

beams inside a heavy ion fusion reactor chamber * Agustin F.of a Heavy Ion Fusion reactor heavily depends on the maximum

Lifschitz, Agustin F.; Maynard, Gilles; Vay, Jean-Luc; Lenglet, Andrian

2006-01-01T23:59:59.000Z

351

Dynamics of neutralizing electrons during the focusing of intense heavy ions beams inside a heavy fusion reactor chamber  

E-Print Network (OSTI)

beams inside a heavy ion fusion reactor chamber * Agustin F.efficiency of a Heavy Ion Fusion reactor heavily depends on

Lifschitz, Agustin F.; Maynard, Gilles; Vay, Jean-Luc; Lenglet, Andrian

2006-01-01T23:59:59.000Z

352

Selenide isotope generator for the Galileo Mission: copper/water axially-grooved heat pipe topical report  

SciTech Connect

This report presents a summary of the major accomplishments for the development, fabrication, and testing of axially-grooved copper/water heat pipes for Selenide Isotopic Generator (SIG) applications. The early development consisted of chemical, physical, and analytical studies to define an axially-grooved tube geometry that could be successfully fabricated and provide the desired long term (up to seven years) performance is presented. Heat pipe fabrication procedures, measured performance and accelerated life testing of heat pipes S/Ns AL-5 and LT-57 conducted at B and K Engineering are discussed. S/N AL-5 was the first axially-grooved copper/water heat pipe that was fabricated with the new internal coating process for cupric oxide (CuO) and the cleaning and water preparation methods developed by Battelle Columbus Laboratories. Heat pipe S/N LT-57 was fabricated along with sixty other axially-grooved heat pipes allocated for life testing at Teledyne Energy Systems. As of June 25, 1979, heat pipes S/Ns AL-5 and LT-57 have been accelerated life tested for 13,310 and 6,292 respectively, at a nominal operating temperature of 225/sup 0/C without any signs of thermal performance degradation. (TFD)

Strazza, N.P.

1979-06-30T23:59:59.000Z

353

Global Circulation in an Axially Symmetric Shallow-Water Model, Forced by Off-Equatorial Differential Heating  

Science Conference Proceedings (OSTI)

An axially symmetric inviscid shallow-water model (SWM) on the rotating Earth forced by off-equatorial steady differential heating is employed to characterize the main features of the upper branch of an ideal Hadley circulation. The steady-state ...

Ori Adam; Nathan Paldor

2010-04-01T23:59:59.000Z

354

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 to completely re-design with five weeks left. This left minimal time for machining, assembly, testing

Demirel, Melik C.

355

Calculation of the heavy-hadron axial couplings g1, g2, and g3 using lattice QCD  

SciTech Connect

In a recent paper [arXiv:1109.2480] we have reported on a lattice QCD calculation of the heavy-hadron axial couplings g{sub 1}, g{sub 2}, and g{sub 3}. These quantities are low-energy constants of heavy-hadron chiral perturbation theory (HH{chi}PT) and are related to the B*B{pi}, {Sigma}{sub b}*{Sigma}{sub b}{pi}, and {Sigma}{sub b}{sup (*)}{Lambda}{sub b}{pi} couplings. In the following, we discuss important details of the calculation and give further results. To determine the axial couplings, we explicitly match the matrix elements of the axial current in QCD with the corresponding matrix elements in HH{chi}PT. We construct the ratios of correlation functions used to calculate the matrix elements in lattice QCD, and study the contributions from excited states. We present the complete numerical results and discuss the data analysis in depth. In particular, we demonstrate the convergence of SU(4|2) HH{chi}PT for the axial current matrix elements at pion masses up to about 400 MeV and show the impact of the nonanalytic loop contributions. Finally, we present additional predictions for strong and radiative decay widths of charm and bottom baryons.

Will Detmold, David Lin, Stefan Meinel

2012-06-01T23:59:59.000Z

356

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

E-Print Network (OSTI)

on lasers, direct drive targets and a dry wall chamber [1]. A primary focus is the development of a tungsten-armored-explosion. Only a thin region of the armor (10-100 µm) will experience the highly cyclic x-ray and ion energy deposition transients. The FW structure behind the armor as well as the blanket will operate under quasi

Raffray, A. René

357

Report on Fission Time Projection Chamber M3FT-12IN0210052  

Science Conference Proceedings (OSTI)

The Time Projection Chamber is a collaborative effort to implement an innovative approach and deliver unprecedented fission measurements to DOE programs. This 4?-detector system will provide unrivaled 3-D data about the fission process. Shown here is a half populated TPC (2?) at the LLNL TPC laboratory as it undergoes testing before being shipped to LANSCE for beam experiments.

James K. Jewell

2012-08-01T23:59:59.000Z

358

Fault Detection and Isolation of a Cryogenic Rocket Engine Combustion Chamber Using a Parity Space Approach  

Science Conference Proceedings (OSTI)

his paper presents a parity space (PS) approach for fault detection and isolation (FDI) of a cryogenic rocket engine combustion chamber. Nominal and non-nominal simulation data for three engine set points have been provided. The PS approach uses three ... Keywords: Fault Detection, Fault Isolation, Fault Diagnosis, Parity Space, Rocket Engine

Paul van Gelder; Andr Bos

2009-07-01T23:59:59.000Z

359

Modeling and Simulation of 1025t/h CFBB Combustion Chamber  

Science Conference Proceedings (OSTI)

This paper takes CFBB as simulating object, which has characters of DG1025/17.4-II1 two legs furnace and with external heat exchanger. Combined with thermal process and combustion chamber working characteristics of practical unit, a general dynamic model ... Keywords: CFB, combustion, modeling, simulation

Chang-liang Liu; Yuan-liang Ma; Lin Chen

2008-10-01T23:59:59.000Z

360

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

E-Print Network (OSTI)

cracking (reaction VII) CH4 + H2O CO + 3H2 steam reforming (reaction VIII) CH4 + CO2 2CO + 2H2 dry.05.118 #12;Abstract Single chamber anode-supported fuel cells are investigated under several methane analyses of anode reduction are performed at 700°C. Carbon deposition is observed under diluted methane

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

Combustion chamber for gas turbines and the like having a fluidized burner bed  

SciTech Connect

A combustion chamber with a fluidized burner bed preferably for gas turbines is described. It contains means for controlling the supply of fuel, combustion air and a cooling medium for the fluidized bed to maintain a predetermined proportional relationship between combustion air and cooling air under varying load conditions.

Harboe, H.

1975-12-09T23:59:59.000Z

362

Nested reactor chamber and operation for Hg-196 isotope separation process  

DOE Patents (OSTI)

The present invention is directed to an apparatus for use in .sup.196 Hg separation and its method of operation. Specifically, the present invention is directed to a nested reactor chamber useful for .sup.196 Hg isotope separation reactions avoiding the photon starved condition commonly encountered in coaxial reactor systems.

Grossman, Mark W. (Belmont, MA)

1991-01-01T23:59:59.000Z

363

A Diffusion Cloud Chamber Study of Very Slow Mesons. II. Beta Decay of the Muon  

DOE R&D Accomplishments (OSTI)

The spectrum of electrons arising from the decay of the negative mu meson has been determined. The muons are arrested in the gas of a high pressure hydrogen filled diffusion cloud chamber. The momenta of the decay electrons are determined from their curvature in a magnetic field of 7750 gauss. The spectrum of 415 electrons has been analyzed according to the theory of Michel.

Lederman, L. M.; Sargent, C. P.; Rinehart, M.; Rogers, K.

1955-03-00T23:59:59.000Z

364

Pulse mode readout techniques for use with non-gridded industrial ionization chambers  

SciTech Connect

Highly sensitive readout technique for precision long-term radiation measurements has been developed and tested in the Radiation Control Department at Jefferson Lab. The new electronics design is used to retrieve ionization data in a pulse mode. The dedicated data acquisition system works with M=Audio Audiophile 192 High-Definition 24-bit/192 kHz audio cards, taking data in continuous waveform recording mode. The on-line data processing algorithms extract signals of the ionization events from the data flow and measure the ionization value for each event. Two different ion chambers are evaluated. The first is a Reuter-Stokes Argon-filled (at 25 atm) High Pressure Ionization Chamber (HPIC), commonly used as a detector part in many GE Reuter-Stokes instruments of the RSS series. The second is a VacuTec Model 70181, 5 atm Xenon-filled ionization chamber. Results for both chambers indicate that the techniques allow using industrial ICs for high sensitivity and precision long-term radiation measurements, while at the same time providing information about spectral characteristics of the radiation fields.

Popov, Vladimir E. [JLAB; Degtiarenko, Pavel V. [JLAB

2011-10-01T23:59:59.000Z

365

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

E-Print Network (OSTI)

, Washington, DC 20375, aerobson@earthlink.net 3 Naval Research Laboratory, Washington, DC 20375, john, Washington, D.C. REFERENCES 1. J. SETHIAN, et al., "An Overview of the Development of the First Wall. RAFFRAY and the HAPL Team, "Threats, Design Limits and Design Windows for Laser IFE Dry Wall Chambers," J

Raffray, A. René

366

A malignant breast carcinoma size assessment using multiple orientation axial, lateral, and shear elastographies: the second stage of a pilot study  

Science Conference Proceedings (OSTI)

Elastography is the imaging modality focusing on detection of stiffness variation within inhomogeneous soft tissue. We extended a conventional 2D axial radio frequency (RF) spline correlation based elastography method to multiple orientations, and strengthened ... Keywords: 2D multiple orientation ultrasound elasticities, axial, lateral, malignant breast cancer, shear strains, size assessment

Ying Chi; Michael J. Brady; Ruth E. English; Junbo Li; J. Alison Noble

2010-09-01T23:59:59.000Z

367

Improving the performance and fuel consumption of dual chamber stratified charge spark ignition engines  

DOE Green Energy (OSTI)

A combined experimental and theoretical investigation of the nature of the combustion processes in a dual chamber stratified charge spark ignition engine is described. This work concentrated on understanding the mixing process in the main chamber gases. A specially constructed single cylinder engine was used to both conduct experiments to study mixing effects and to obtain experimental data for the validation of the computer model which was constructed in the theoretical portion of the study. The test procedures are described. Studies were conducted on the effect of fuel injection timing on performance and emissions using the combination of orifice size and prechamber to main chamber flow rate ratio which gave the best overall compromise between emissions and performance. In general, fuel injection gave slightly higher oxides of nitrogen, but considerably lower hydrocarbon and carbon monoxide emissions than the carbureted form of the engine. Experiments with engine intake port redesign to promote swirl mixing indicated a substantial increase in the power output from the engine and, that an equivalent power levels, the nitric oxide emissions are approximately 30% lower with swirl in the main chamber than without swirl. The development of a computer simulation of the combustion process showed that a one-dimensional combustion model can be used to accurately predict trends in engine operation conditions and nitric oxide emissions even though the actual flame in the engine is not completely one-dimensional, and that a simple model for mixing of the main chamber and prechamber intake gases at the start of compression proved adequate to explain the effects of swirl, ignition timing, overall fuel air ratio, volumetric efficiency, and variations in prechamber air fuel ratio and fuel rate percentage on engine power and nitric oxide emissions. (LCL)

Sorenson, S.C.; Pan, S.S.; Bruckbauer, J.J.; Gehrke, G.R.

1979-09-01T23:59:59.000Z

368

Fabrication of The Multi-PCR Chamber With Inner Heat-Sink Materials Using a Micro-Blaster Etching Technique  

Science Conference Proceedings (OSTI)

In this paper, we propose a new design for a PCR (Polymerase Chain Reaction) chamber with a temperature sensor under a top glass wafer and heaters on the bottom glass wafer. These chamber sensors are thermally isolated from the heater. The multi PCR ...

Hyoung-Jin Park; Duk-Soo Eun; Dae-Young Kong; Seong-Jin Kong; Seong-Ho Kong; Jong-Hyun Lee

2005-07-01T23:59:59.000Z

369

LS-266 OPTIMIZATION OF FOUR-BUTTON BEAM POSITION MONITOR CONFIGURATION FOR SMALL-GAP VACUUM CHAMBERS  

NLE Websites -- All DOE Office Websites (Extended Search)

LS-266 LS-266 OPTIMIZATION OF FOUR-BUTTON BEAM POSITION MONITOR CONFIGURATION FOR SMALL-GAP VACUUM CHAMBERS S. H. Kim March 27, 1998 Summary - Induced charges on a four-button beam position monitor (BPM) system attached on a beam chamber of narrow rectangular cross sections are calculated as a 2-D electrostatic problem of image charges. The calculation shows that for a narrow chamber of width/height (2w/2h) >> 1, over 90% of the induced charges are distributed within a distance of 2h from the charged beam position in the direction of the chamber width. Therefore, a four-button system with a button diameter of (2 ~ 2.5)h and no button offset from the beam position is the most efficient configuration. The four-button BPMs used for 8-mm and 5-mm chambers in the APS have relatively low sensitivities because the button locations are outside

370

Active Control of an Axial Flow Compressor via Pulsed Air Injection  

E-Print Network (OSTI)

This paper presents the use of pulsed air injection to control the onset of rotating stall in a low-speed, axial flow compressor. By measuring the unsteady pressures near the rotor face, a control algorithm determines the magnitude and phase of the first mode of rotating stall and controls the injection of air in the front of the rotor face. Experimental results show that this technique slightly extends the stall point of the compressor and eliminates the hysteresis loop normally associated with rotating stall. A parametric study is used to determine the optimal control parameters for suppression of stall. Analytic results---using a low-dimensional model developed by Moore and Greitzer combined with an unsteady shift in the compressor characteristic to model the injectors---give further insights into the operation of the controller. Based on this model, we show that the behavior of the experiment can be explained as a change in the bifurcation behavior of the system under non...

Raffaello D' Andrea; Robert L. Behnken; Richard M. Murray; Asme J. Turbomachinery

1996-01-01T23:59:59.000Z

371

Trapped and escaping orbits in an axially symmetric galactic-type potential  

E-Print Network (OSTI)

In the present article, we investigate the behavior of orbits in a time independent axially symmetric galactic type potential. This dynamical model can be considered to describe the motion in the central parts of a galaxy, for values of energies larger than the energy of escape. We use the classical method of the surface of section, in order to visualize and interpret the structure of the phase space of the dynamical system. Moreover, the Lyapunov Characteristic Exponent (LCE), is used in order to make an estimation of the degree of the chaoticity of the orbits in our galactic model. Our numerical calculations suggest that in this galactic type potential, there are two kinds of orbits: (i) escaping orbits and (ii) trapped orbits which do not escape at all. Furthermore, a large number of orbits of the dynamical system, display chaotic motion. Among the chaotic orbits, there are orbits that escape fast and also orbits that remain trapped for vast time intervals. When the value of the test particle's energy exce...

Zotos, Euaggelos E

2012-01-01T23:59:59.000Z

372

Ultra-high speed permanent magnet axial gap alternator with multiple stators  

DOE Patents (OSTI)

An ultra-high speed, axial gap alternator that can provide an output to a plurality of loads, the alternator providing magnetic isolation such that operating conditions in one load will not affect operating conditions of another load. This improved alternator uses a rotor member disposed between a pair of stator members, with magnets disposed in each of the rotor member surfaces facing the stator members. The magnets in one surface of the rotor member, which alternate in polarity, are isolated from the magnets in the other surface of the rotor member by a disk of magnetic material disposed between the two sets of magents. In the preferred embodiment, this disk of magnetic material is laminated between two layers of non-magnetic material that support the magnets, and the magnetic material has a peripheral rim that extends to both surfaces of the rotor member to enhance the structural integrity. The stator members are substantially conventional in construction in that equally-spaced and radially-oriented slots are provided, and winding members are laid in these slots. A unit with multiple rotor members and stator members is also described.

Hawsey, Robert A. (Oak Ridge, TN); Bailey, J. Milton (Knoxville, TN)

1991-01-01T23:59:59.000Z

373

Hydrogen turbines for space power systems: A simplified axial flow gas turbine model  

SciTech Connect

This paper descirbes a relatively simple axial flow gas expansion turbine mass model, which we developed for use in our space power system studies. The model uses basic engineering principles and realistic physical properties, including gas conditions, power level, and material stresses, to provide reasonable and consistent estimates of turbine mass and size. Turbine design modifications caused by boundary layer interactions, stress concentrations, stage leakage, or bending and thermal stresses are not accounted for. The program runs on an IBM PC, uses little computer time and has been incorporated into our system-level space power platform analysis computer codes. Parametric design studies of hydrogen turbines using this model are presented for both nickel superalloy and carbon/carbon composite turbines. The effects of speed, pressure ratio, and power level on hydrogen turbine mass are shown and compared to a baseline case 100-MWe, 10,000-rpm hydrogen turbine. Comparison with more detailed hydrogen turbine designs indicates that our simplified model provides mass estimates that are within 25% of the ones provided by more complex calculations. 8 figs.

Hudson, S.L.

1988-01-01T23:59:59.000Z

374

Deformation Behavior and TExture Evolution of Steel Alloys under Axial-Torsional Loading  

SciTech Connect

Using hollow cylinder samples with suitable geometry obtained from round bar stock, the deformation behavior of bcc Fe based 12L14 steel alloy is evaluated under multi-axial conditions. A stacked strain gage rosette and extensometer mounted on the cylindrical surface at the mid height of the specimen provided strain tensor as a function of applied stress for pure tensile and torsion tests prior to yielding. This study examines elastic and yield behavior and effects of these with respect to texture evolution. Hollow cylinder specimen geometry (tubes) with small wall thickness and relatively (to its thickness) large inner diameter is used. The variation of observed yield surface in deviatoric plane and the effect on mode of deformation (tension versus torsion versus its combination) on stress-strain behavior is discussed. Bulk texture was studied using neutron time-of-flight diffractometer at High-Pressure-Preferred Orientation (HIPPO) - Los Alamos Neutron Science Center (LANSCE) instrument and the evolution of texture and related anisotropy for pure tension versus torsion are also included.

Siriruk, A.; Kant, M.; Penumadu, D.; Garlea, E.; Vogel, S.

2011-06-01T23:59:59.000Z

375

Mode conversion between Alfven wave eigenmodes in axially inhomogeneous two-ion-species plasmas  

DOE Green Energy (OSTI)

The uniform cylindrical plasma model of Litwin and Hershkowitz (Phys. Fluids {bold 30}, 1323 (1987)) is shown to predict mode conversion between the lowest radial order {ital m}=+1 fast magnetosonic surface and slow ion-cyclotron global eigenmodes of the Alfven wave at the light-ion species Alfven resonance of a cold two-ion plasma. A hydrogen ({ital h})--deuterium ({ital d}) plasma is examined in experiments. The fast mode is efficiently excited by a rotating field antenna array at {omega}{similar to}{Omega}{sub {ital h}} in the central cell of the Phaedrus-B tandem mirror (Phys. Rev. Lett. {bold 51}, 1955(1983)). Radially scanned magnetic probes observe the propagating eigenmode wave fields within a shallow central cell magnetic gradient in which the conversion zone is axially localized according to {ital n}{sub {ital d}}/{ital n}{sub {ital h}}. A low radial-order slow ion-cyclotron mode, observed in the vicinity of the conversion zone, gives evidence for the predicted mode conversion.

Roberts, D.R.; Hershkowitz, N.; Tataronis, J.A. (Department of Nuclear Engineering Department of Engineering Physics, University of Wisconsin, Madison, Wisconsin 53706 (USA))

1990-04-01T23:59:59.000Z

376

Axial flux, modular, permanent-magnet generator with a toroidal winding for wind turbine applications  

SciTech Connect

Permanent-magnet generators have been used for wind turbines for many years. Many small wind turbine manufacturers use direct-drive permanent-magnet generators. For wind turbine generators, the design philosophy must cover the following characteristics: low cost, light weight, low speed, high torque, and variable speed generation. The generator is easy to manufacture and the design can be scaled up for a larger size without major retooling. A modular permanent-magnet generator with axial flux direction was chosen. The permanent magnet used is NdFeB or ferrite magnet with flux guide to focus flux density in the air gap. Each unit module of the generator may consist of one, two, or more phases. Each generator can be expanded to two or more unit modules. Each unit module is built from simple modular poles. The stator winding is formed like a torus. Thus, the assembly process is simplified and the winding insertion in the slot is less tedious. The authors built a prototype of one unit module and performed preliminary tests in the laboratory. Follow up tests will be conducted in the lab to improve the design.

Muljadi, E.; Butterfield, C.P.; Wan, Y.H.

1998-07-01T23:59:59.000Z

377

Apparatus for positioning a sample in a computerized axial tomographic scanner  

SciTech Connect

An apparatus is described for positioning a sample in a radiation field of a computerized axial tomographic scanner (CAT) for scanning by the CAT, the apparatus comprising: a first support means positioned on a first side of the CAT having a first guide means; a first trolly means having means for engaging the first guide means; means for moving the first trolley means along the first guide means; a second support means positioned on a second side of the CAT, the second side being opposite the first side and the second support means having a second guide means; a second trolley means having means for engaging the second guide means; means for coupling the first trolley means to the second trolley means such that movement of the first trolley means causes similar movement of the second trolley means, the coupling means passing through the radiation field of the CAT; means attached to the coupling means for holding the sample; means for sensing the position of the sample holding means; and control means connected to the moving means and sensing means for controlling the positioning of the sample.

Vinegar, H.J.; Wellington, S.L.

1986-04-15T23:59:59.000Z

378

Axial strength of cement borehole plugs in granite and basalt. Topical report on rock mass sealing  

SciTech Connect

This report describes experimental and theoretical studies of the axial strength of cement plugs installed in boreholes drilled coaxially in granite and in basalt cylinders. Experimental work has consisted of loading the cement plugs to failure while measuring loads and displacements. Such tests have been performed on borehole plugs with a diameter and a length ranging from 2.5 cm to 10 cm. Results from over one hundred experiments show that the strength is high, sufficient for anticipated loads at repository depths, but very variable, complicating the design of very short plugs. Significant residual strength (thirty to fifty percent of the peak strength) is observed. A frictional model of the interface shear strength, tau = c + sigma(tan phi), in combination with the assumption of an exponential shear stress distribution or plug-rock load transfer, provides the simplest realistic model for plug strength characterization. The integrated strength thus calculated compares moderately well with experimental results. An extensive review is given of more sophisticated analysis procedures that should be of value for general plug design applications. Generic analyses and their implications for plug performance are included. Variability of experimental results complicates the assessment of their direct detailed applicability. 115 references, 70 figures, 19 tables.

Stormont, J.C.; Daemen, J.J.K.

1983-12-01T23:59:59.000Z

379

Power source for an axial-flow CO/sub 2/laser tube  

SciTech Connect

A power device is described for an axial-flow-type CO/sub 2/ laser shell comprising: a high voltage DC power source directly connected to a cathode of the laser shell, in which a discharge for laser pumping takes place, for applying a constant high DC voltage to the cathode; and a high voltage pulse power source connected through a ballast resistance to an anode of the laser shell for applying a high pulse voltage to the anode, the high voltage pulse power source having a DC power circuit, a switching element having a first terminal to receive a command signal instructing switching operation, and second and third terminals connected or disconnected by the switching operation, the second terminal being connected to the DC power circuit and the third terminal being connected to the anode of the laser shell through ballast resistance, and a PWM controller having an output terminal connected to the first terminal of the switching element, for outputting a pulsed voltage with a predetermined repetition frequency and width, as the command signal.

Koseki, R.

1988-12-27T23:59:59.000Z

380

Constraints on Two-Body Axial Currents from Reactor Antineutrino-Deuteron Breakup Reactions  

E-Print Network (OSTI)

We discuss how to reduce theoretical uncertainties in the neutrino-deuteron breakup cross-sections crucial to the Sudbury Neutrino Observatory's efforts to measure the solar neutrino flux. In effective field theory, the dominant uncertainties in all neutrino-deuteron reactions can be expressed through a single, common, isovector axial two-body current parameterized by $L_{1,A}$. After briefly reviewing the status of fixing $L_{1,A}$ experimentally, we present a constraint on $L_{1,A}$ imposed by existing reactor antineutrino-deuteron breakup data. This constraint alone leads to an uncertainty of 6-7% at 7 MeV neutrino energy in the cross-sections relevant to the Sudbury Neutrino Observatory. However, more significantly for the Sudbury experiment, the constraint implies an uncertainty of only 0.7% in the ratio of charged to neutral current cross-sections used to verify the existence of neutrino oscillations, at the same energy. This is the only direct experimental constraint from the two-body system, to date, of the uncertainty in these cross-sections.

Malcolm Butler; Jiunn-Wei Chen; Petr Vogel

2002-06-11T23:59:59.000Z

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

Processing of O.F.E. copper beam chambers for PEP-II high energy ring  

DOE Green Energy (OSTI)

Using laboratory scale and full size PEP-II vacuum chambers, chemical cleaning, glow discharge and thermal process effects were evaluated using surface analysis by x-ray photoelectron spectroscopy (XPS). These processes were optimized to reduce surface carbon and thereby minimize photodesorption gas loads. The relation of surface carbon to ion dose was investigated and compared for pure argon, 5% oxygen in argon, and pure hydrogen plasmas. Argon incorporation was noted only when the copper was oxidized in the mixed gas. Surfaces, stable in ambient atmosphere, were obtained having surface carbon values less than 10%. These optimized recipes will be used in processing copper vacuum chambers for the PEP-II B-Factory.

Hoyt, E.; Hoyt, M.; Kirby, R.; Perkins, C.; Wright, D.; Farvid, A.

1995-08-01T23:59:59.000Z

382

HYDROGEN OUTGASSING AND SURFACE PROPERTIES OF TIN COATED STAINLESS STEEL CHAMBERS.  

DOE Green Energy (OSTI)

The stainless steel vacuum chambers of the 248m accumulator ring of Spallation Neutron Source (SNS) are coated with {approx} 100 nm of titanium nitride (TiN) to reduce the secondary electron yield. The coating is produced by DC magnetron sputtering using a long cathode imbedded with permanent magnets. The outgassing rates of several SNS half-cell chambers were measured with and without TiN coating, and before and after in-situ bake. One potential benefit of a TiN coating is to serve as hydrogen permeation barrier that reduces the ultimate outgassing rate. By varying the coating parameters, films of different surface roughness were produced and analyzed by Auger electron spectroscopy, scanning electron microscopy and atomic force microscopy to illustrate the dependence of the outgassing on the film structure.

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

2002-11-11T23:59:59.000Z

383

Model of High Current Breakdown from Cathode Field Emission in Aged Wire Chambers  

SciTech Connect

Observing single electron pulses provides insight into the mechanism that leads to sudden high current jumps (breakdown) in aged wire chambers. This single electron activity is found to be consistent with the Fowler-Nordheim equation for field emission of electrons from a cathode surface in a high electric field. The high electric field arises from the positive ion buildup on a very thin insulating layer on the cathode surface. A model is presented to explain the transient behavior of single electron pulses in response to abrupt changes in chamber ionization, as well as the steady state rate during a long term aging run. The model is based on properties of the insulating layer (dielectric constant, conductivity, and hole-mobility) as well as the Fowler-Nordheim equation.

Boyarski, A

2004-02-25T23:59:59.000Z

384

Trapped and escaping orbits in an axially symmetric galactic-type potential  

E-Print Network (OSTI)

In the present article, we investigate the behavior of orbits in a time independent axially symmetric galactic type potential. This dynamical model can be considered to describe the motion in the central parts of a galaxy, for values of energies larger than the energy of escape. We use the classical method of the surface of section, in order to visualize and interpret the structure of the phase space of the dynamical system. Moreover, the Lyapunov Characteristic Exponent (LCE), is used in order to make an estimation of the degree of the chaoticity of the orbits in our galactic model. Our numerical calculations suggest that in this galactic type potential, there are two kinds of orbits: (i) escaping orbits and (ii) trapped orbits which do not escape at all. Furthermore, a large number of orbits of the dynamical system, display chaotic motion. Among the chaotic orbits, there are orbits that escape fast and also orbits that remain trapped for vast time intervals. When the value of the test particle's energy exceeds slightly the energy of escape, the amount of the trapped regular orbits increases, as the the value of the angular momentum increases. Therefore, the extent of the chaotic regions observed in the phase plane decreases as the value of the energy increases. Moreover, we calculate the average value of the escape period of the chaotic orbits and we try to correlate it with the value of the energy and also with the maximum value of the z component of the orbits. In addition, we find that the value of the LCE corresponding to each chaotic region, for different values of the energy, increases exponentially as the value of the energy increases. Some theoretical arguments in order to support the numerically obtained outcomes are presented.

Euaggelos E. Zotos

2012-06-12T23:59:59.000Z

385

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

386

Challenges Surrounding the Injection and Arrival of Targets at LIFE Fusion Chamber Center  

SciTech Connect

IFE target designers must consider several engineering requirements in addition to the physics requirements for successful target implosion. These considerations include low target cost, high manufacturing throughput, the ability of the target to survive the injection into the fusion chamber and arrive in a condition and physical position consistent with proper laser-target interaction and ease of post-implosion debris removal. This article briefly describes these considerations for the Laser Inertial Fusion-based Energy (LIFE) targets currently being designed.

Miles, R; Spaeth, M; Manes, K; Amendt, P; Tabak, M; Bond, T; Kucheyev, S; Latkowski, J; Loosmore, G; Bliss, E; Baker, K; Bhandarkar, S; Petzoldt, R; Alexander, N; Tillack, M; Holdener, D

2010-12-01T23:59:59.000Z

387

PRE-SW Aging Chamber Report Tool (ACRT) Version 6.0, Beta  

Science Conference Proceedings (OSTI)

The 230kV Accelerated Aging Chamber is a multi-year test of more than 50 polymer and fiberglass components. Photographic inspections occur twice a year. Thousands of photographs accumulate making conventional reports difficult to read. This reporting tool enables the reader to jump from component to component and inspection to inspection. The reader can easily compare components at different levels of aging. This tool will make reviewing the important results of this ...

2013-08-11T23:59:59.000Z

388

Performance of Glass Resistive Plate Chambers for a high granularity semi-digital calorimeter  

E-Print Network (OSTI)

A new design of highly granular hadronic calorimeter using Glass Resistive Plate Chambers (GRPCs) with embedded electronics has been proposed for the future International Linear Collider (ILC) experiments. It features a 2-bit threshold semi-digital read-out. Several GRPC prototypes with their electronics have been successfully built and tested in pion beams. The design of these detectors is presented along with the test results on efficiency, pad multiplicity, stability and reproducibility.

Bedjidian, M; Boudry, V; Combaret, C; Decotigny, D; Gil, E Cortina; de la Taille, C; Dellanegra, R; Gapienko, V A; Grenier, G; Jauffret, C; Kieffer, R; Fouz, M -C; Han, R; Laktineh, I; Lumb, N; Manai, K; Mannai, S; Mathez, H; Mirabito, L; Pelayo, J Puerta; Ruan, M; Schirra, F; Seguin-Moreau, N; Tromeur, W; Tytgat, M; Donckt, M Vander; Zaganidis, N

2010-01-01T23:59:59.000Z

389

Apparatus for monitoring tritium in tritium contaminating environments using a modified Kanne chamber  

SciTech Connect

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

390

Fusion Engineering and Design 42 (1998) 537548 Chamber technology concepts for inertial fusion energy--three  

E-Print Network (OSTI)

to 650°C and has a low enough vapor pressure. Li and Li17Pb83 would also work but must be 1.5 m thick and increased pumping power features required by use of Li or Li17Pb83 suggest Flibe might be the lowest cost to a large variety of chamber design concepts for inertial fusion energy (IFE). Refs. [1­8] provide

Abdou, Mohamed

391

Interpretation of Secondary Organic Aerosol Formation from Diesel Exhaust Photooxidation in an Environmental Chamber  

Science Conference Proceedings (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

392

Inertial confinement fusion reaction chamber and power conversion system study. Final report  

Science Conference Proceedings (OSTI)

This report summarizes the results of the second year of a two-year study on the design and evaluation of the Cascade concept as a commercial inertial confinement fusion (ICF) reactor. We developed a reactor design based on the Cascade reaction chamber concept that would be competitive in terms of both capital and operating costs, safe and environmentally acceptable in terms of hazard to the public, occupational exposure and radioactive waste production, and highly efficient. The Cascade reaction chamber is a double-cone-shaped rotating drum. The granulated solid blanket materials inside the rotating chamber are held against the walls by centrifugal force. The fusion energy is captured in a blanket of solid carbon, BeO, and LiAlO/sub 2/ granules. These granules are circulated to the primary side of a ceramic heat exchanger. Primary-side granule temperatures range from 1285 K at the LiAlO/sub 2/ granule heat exchanger outlet to 1600 K at the carbon granule heat exchanger inlet. The secondary side consists of a closed-cycle gas turbine power conversion system with helium working fluid, operating at 1300 K peak outlet temperature and achieving a thermal power conversion efficiency of 55%. The net plant efficiency is 49%. The reference design is a plant producing 1500 MW of D-T fusion power and delivering 815 MW of electrical power for sale to the utility grid. 88 refs., 44 figs., 47 tabs.

Maya, I.; Schultz, K.R.; Bourque, R.F.; Cheng, E.T.; Creedon, R.L.; Norman, J.H.; Price, R.J.; Porter, J.; Schuster, H.L.; Simnad, M.J.

1985-10-01T23:59:59.000Z

393

Laser cooling in the Penning trap: an analytical model for cooling rates in the presence of an axializing field  

E-Print Network (OSTI)

Ions stored in Penning traps may have useful applications in the field of quantum information processing. There are, however, difficulties associated with the laser cooling of one of the radial motions of ions in these traps, namely the magnetron motion. The application of a small radio-frequency quadrupolar electric potential resonant with the sum of the two radial motional frequencies has been shown to couple these motions and to lead to more efficient laser cooling. We present an analytical model that enables us to determine laser cooling rates in the presence of such an 'axializing' field. It is found that this field leads to an averaging of the laser cooling rates for the two motions and hence improves the overall laser cooling efficiency. The model also predicts shifts in the motional frequencies due to the axializing field that are in qualitative agreement with those measured in recent experiments. It is possible to determine laser cooling rates experimentally by studying the phase response of the cooled ions to a near resonant excitation field. Using the model developed in this paper, we study the expected phase response when an axializing field is present.

R. J. Hendricks; E. S. Phillips; D. M. Segal; R. C. Thompson

2007-09-24T23:59:59.000Z

394

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 covalent bond. The structure of molecular complexes such as those formed between a rare gas and a hydrogen halide, Rg:HX where Rg is a rare gas (Rg=Ne, Ar and Kr) and HX (X=F, Cl, Br and I) can be determined directly and accurately. The center of mass interaction distance, RCM, as well as the angle of the hydrogen halide is determined, along with direct evaluation of the intermolecular vibrations as well as accurate isomerization energies between the hydrogen bound and van der Waals forms. The accuracy of the frequency determination of rovibrational transitions using the submillimeter spectrometer is also evaluated by direct comparison with the state-of-theart pulsed nozzle Fourier transform microwave spectrometer, and this accuracy is estimated to be less than 1 kHz at 300 GHz. The tunneling or geared bending vibration of a dimer of hydrogen bromide or hydrogen iodide has been investigated. The selection rules, nuclear statistics and intensity alternation for transitions observed in these dimmers, which is a consequence of interchanging two identical nuclei in the low frequency geared bending vibration of the molecular complex, are reported. Furthermore, the rotation and quadrupole coupling constants are used to determine a vibrationally averaged structure of the complex. The energy of the low frequency bending vibration can then be compared with ab initio based potential energy surfaces. A study of the multiple isomeric forms of the molecular complex OC:HI is also presented. Multiple isotopic substitutions are used to determine the relevant ground state structures and data reported evidence for an anomalous isotope effect supporting a ground state isotopic isomerization effect. All spectroscopic data that has been reported here has been additionally used to subsequently model and generate vibrationally complete morphed potential energy surfaces that are capable or reproducing the experimentally observed data. The utility of this procedure is evaluated on a predicative basis and comparisons made with newly observed data.

McElmurry, Blake Anthony

2008-12-01T23:59:59.000Z

395

Strange Quark Contribution to the Vector and Axial Form Factors of the Nucleon: Combined Analysis of G0, HAPPEx, and Brookhaven E734 Data  

E-Print Network (OSTI)

The strange quark contribution to the vector and axial form factors of the nucleon has been determined for momentum transfers in the range $0.45Lab, and elastic $\

S. F. Pate; D. W. McKee; V. Papavassiliou

2008-05-19T23:59:59.000Z

396

Detecting Ice Nuclei with a ContinuousFlow Diffusion Chamber-Some Exploratory Tests of Instrument Response  

Science Conference Proceedings (OSTI)

A few basic experiments were performed with artificial cloud condensation nuclei and ice-nucleating aerosols in a continuous-flow thermal gradient diffusion chamber to investigate the instrument's response. Brief pulses of ice nuclei were input ...

David C. Rogers

1994-08-01T23:59:59.000Z

397

Measurement of the propagation velocity of single plasma channels in a spark chamber for particle track detection  

SciTech Connect

The velocity of growth of single tracks in a spark chamber is described. It is shown thai in the pressure range 300 < p < 760 torr the tracks propagate with the same velocity to the anode and cathode provided that E/p remains below an experimentally determined value. A rise of this value causes an asymmetry, which makes the chamber no longer suited for the track localization of ionizing particles. (GE)

Timm, U.

1972-01-01T23:59:59.000Z

398

Sweet Lake Geopressured-geothermal Project, Magma Gulf-Technadril/DOE Amoco Fee. Volume II. Surface installations reservoir testing. Annual report, February 28, 1981-February 10, 1982  

DOE Green Energy (OSTI)

The Magma Gulf-Technadril/Department of Energy Amoco Fee No. 1 (production) and salt water disposal wells were drilled in the period from August, 1980 to February 1981. Surface facilities were designed and constructed during March-June 1981. Flow testing began in June 1981 and continued until February, 1982. The Miogypsinoides interval contains seven discrete sands in the test well. These sands have been numbered 1 to 7, beginning at the top of the sequence. Data from wireline logs and core samples suggested that the first zone to be perforated should be Sand 5. Because of its high porosity and permeability, Sand 5 was thought to contain almost 50% of the total hydraulic capacity of the well. Flow testing of Sand 5 was performed in three stages, each of which is fully described in this report. Phase I was designed as an initial clean-up flow and a reservoir confirmation test. Phase II consisted of the reservoir limit determination test and lasted 17 days. Boundaries were confirmed which suggest that the Sweet Lake reservoir is fairly narrow, with boundaries on three sides, but is open in one direction with no closure for at least 4-1/4 miles. These boundaries approximate the shape of the graben in which the test well was drilled, but may or may not be directly related to the major faults forming the graben. Phase III testing was planned to be a long-term test at commercial design rates. Although Sand 5 alone would not support such rates, long-term production was demonstrated. Additional research not supported by DOE funding was also performed during the period covered by this report. This research, consisting of mud logging, micropaleontology, organic geochemistry, core analysis, and rock mechanics, is summarized in this report.

Hoffman, K.S. (ed.)

1984-01-01T23:59:59.000Z

399

Filling the vacuum chamber of a technological system with homogeneous plasma using a stationary glow discharge  

Science Conference Proceedings (OSTI)

Experimental study of a glow discharge with electrostatic confinement of electrons is carried out in the vacuum chamber volume V {approx} 0.12 m{sup 3} of a technological system 'Bulat-6' in argon pressure range 0.005-5 Pa. The chamber is used as a hollow cathode of the discharge with the inner surface area S {approx} 1.5 m{sup 2}. It is equipped with two feedthroughs, which make it possible to immerse in the discharge plasma interchangeable anodes with surface area S{sub a} ranging from {approx}0.001 to {approx}0.1 m{sup 2}, as well as floating electrodes isolated from both the chamber and the anode. Dependences of the cathode fall U{sub c} = 0.4-3 kV on the pressure p at a constant discharge current in the range I = 0.2-2 A proved that aperture of the electron escape out of the electrostatic trap is equal to the sum S{sub o} = S{sub a} + S{sub f} of the anode surface S{sub a} and the floating electrode surface S{sub f}. The sum S{sub o} defines the lower limit p{sub o} of the pressure range, in which U{sub c} is independent of p. At p fall U{sub c} grows up dramatically, when the pressure decreases, and the pressure p tends to the limit p{sup ex}, which is in fact the discharge extinction pressure. At p {approx} p{sup ex} electrons emitted by the cathode and the first generation of fast electrons produced in the cathode sheath spend almost all their energy up to 3 keV on heating the anode and the floating electrode up to 600-800{sup o}C and higher. In this case the gas in the chamber is being ionized by the next generations of electrons produced in the cathode sheath, their energy being one order of magnitude lower. When S{sub a} fall of potential U{sub a} up to 0.5 kV.

Metel, A. S., E-mail: ametel@stankin.ru; Grigoriev, S. N.; Melnik, Yu. A.; Panin, V. V. [Moscow State University of Technology 'Stankin' (Russian Federation)

2009-12-15T23:59:59.000Z

400

Voltage Pulse Profile Characteristics with Space Charge of a Loaded Pulsed Ionization Chamber  

Science Conference Proceedings (OSTI)

An analytical model describing the voltage pulse profile of a pulsed ionization chamber and its relationship to the electron density in a field drift dominated plasma is formulated. The differential equation derived from the equations of motion and conservation of electron density combined with Poisson's equation for the electric space?charge field in the system is solved analytically for the cylindrical?electrode geometry with an external RC circuit. The numerical analysis for the given initial and boundary conditions yields the anode voltage?signal pulse profiles for the period of electron collection as a function of the initial electron density

S.H. Kim; W.H. Ellis

1972-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "axial magma chamber" from the National Library of EnergyBeta (NLEBeta).
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401

Direct measurement of the impulse in a magnetic thrust chamber system for laser fusion rocket  

Science Conference Proceedings (OSTI)

An experiment is conducted to measure an impulse for demonstrating a magnetic thrust chamber system for laser fusion rocket. The impulse is produced by the interaction between plasma and magnetic field. In the experiment, the system consists of plasma and neodymium permanent magnets. The plasma is created by a single-beam laser aiming at a polystyrene spherical target. The impulse is 1.5 to 2.2 {mu}Ns by means of a pendulum thrust stand, when the laser energy is 0.7 J. Without magnetic field, the measured impulse is found to be zero. These results indicate that the system for generating impulse is working.

Maeno, Akihiro; Yamamoto, Naoji; Nakashima, Hideki [Interdisciplinary Graduate School of Engineering Science, Kyushu University, 6-1 Kasuga-kouen, Kasuga, Fukuoka 816-8580 (Japan); Fujioka, Shinsuke; Johzaki, Tomoyuki [Institute of Laser Engineering, Osaka University, Suita, Osaka 565-087 (Japan); Mori, Yoshitaka [Graduate School for the Creation of New Photonics Industries, Hamamatsu, Shizuoka 431-1202 (Japan); Sunahara, Atsushi [Institute for Laser Technology, Suita, Osaka 565-087 (Japan)

2011-08-15T23:59:59.000Z

402

Analysis of Combustion Chamber Deposits by ESI-TOF-MS and MALDI-TOF-MS  

DOE Green Energy (OSTI)

Combustion chamber deposits (CCDs) in internal combustion engines have been studied by various techniques to understand the relationship of performance degradation with deposit quantity and structure. XPS, XAS, NMR, and elemental analysis have offered insight into the bulk structure of C, H, N, O and metal components [1]. MS has offered some information about compound structure, but results are limited due to the insolubility and complexity of the materials. Recent advances in MS have opened new possibilities for analysis of CCDs. Here we report initial findings on the carbon structure of these deposits determined by ESI-TOF-MS and MADLI-TOF-MS.

Reynolds, J G; Shields, S J; Roos, J W

2001-06-14T23:59:59.000Z

403

Measurement of the axial distribution of radioactivity in the auxiliary charcoal bed of the Molten Salt Reactor Experiment at ORNL  

SciTech Connect

The Molten Salt Reactor Experiment (MSRE) at Oak Ridge National Laboratory commenced operation in 1964 and was shut down in 1969. It was fueled with {sup 233}UF{sub 4} in a carrier salt of LiF-BeF{sub 2}-ZrF{sub 4}, and it operated at 1,200 F. After it was shut down, the fuel was heated annually to 200 C to recombine fluorine (with the fuel) released due to radiation-induced reactions in the fuel salt. However, a competing reaction oxidized uranium to UF{sub 6}, which was released (along with F{sub 2}) from the fuel and trapped in one of four charcoal filters in the auxiliary charcoal bed (ACB). One of the tasks for decommissioning of the MSRE requires that at least 90% of the estimated 3 kg of {sup 233}U, and radioactive decay products, in this filter be removed, and one of the proposed methods is to vacuum the charcoal above a specified axial position in the filter. This requires that the axial distribution of activity in the filter be measured in a 60 rad/h radiation field to determine where this penetration can be made. To accomplish this, the shielded detector with a pinhole collimator, and with a laser positioning capability, was remotely translated to various axial positions to accomplish these measurements. Activities in the steel screen, and various regions of the charcoal bed, are estimated, and uncertainties in these estimates are generally {lt}1%. Results from this analysis are used for continued operational decisions for decommissioning of the MSRE.

Miller, L.F.; Buckner, M.; Buchanan, M.

1999-07-01T23:59:59.000Z

404

Baryon-Number-Induced Chern-Simons Couplings of Vector and Axial-Vector Mesons in Holographic QCD  

Science Conference Proceedings (OSTI)

We show that holographic models of QCD predict the presence of a Chern-Simons coupling between vector and axial-vector mesons at finite baryon density. In the Anti de Sitter/Conformal Field Theory dictionary, the coefficient of this coupling is proportional to the baryon number density and is fixed uniquely in the five-dimensional holographic dual by anomalies in the flavor currents. For the lightest mesons, the coupling mixes transverse {rho} and a{sub 1} polarization states. At sufficiently large baryon number densities, it produces an instability, which causes the {rho} and a{sub 1} mesons to condense in a state breaking both rotational and translational invariance.

Domokos, Sophia K.; Harvey, Jeffrey A. [Enrico Fermi Institute and Department of Physics, University of Chicago, Chicago, Illinois 60637 (United States)

2007-10-05T23:59:59.000Z

405

Acceleration of electrons by a circularly polarized laser pulse in the presence of an intense axial magnetic field in vacuum  

Science Conference Proceedings (OSTI)

Acceleration of electrons by a circularly polarized laser pulse in the presence of a short duration intense axial magnetic field has been studied. Resonance occurs between the electrons and the laser field for an optimum magnetic field leading to effective energy transfer from laser to electrons. The value of optimum magnetic field is independent of the laser intensity and decreases with initial electron energy. The electrons rotate around the axis of the laser pulse with small angle of emittance and small energy spread. Acceleration gradient increases with laser intensity and decreases with initial electron energy.

Singh, K. P. [Computational Plasma Dynamics Laboratory, Kettering University, Flint, Michigan 48504 (United States)

2006-08-15T23:59:59.000Z

406

Design and optimization of 6li neutron-capture pulse mode ion chamber  

E-Print Network (OSTI)

The purpose of this research is to design and optimize the performance of a unique, inexpensive 6Li neutron-capture pulse-mode ion chamber (LiPMIC) for neutron detection that overcomes the fill-gas contamination stemming from outgas of detector components. This research also provides a demonstration of performance of LiPMICs. Simulations performed with GARFIELD, a drift-chamber simulation package for ion transport in an electrostatic field, have shown that argon-methane mixtures of fill-gas allow maintenance of electron drift velocity through a surprisingly wide range of fill-gas content. During the design stage of LiPMIC development, the thicknesses of lithium metallization layer, the neutron energy conversion site of the detector, and the thickness of neutron moderator, the high-density polyethylene body, are optimized through analytical and MCNPX calculations. Also, a methodology of obtaining the suitable combination of electric field strength, electron drift velocity, and fill-gas mixtures has been tested and simulated using argon-methane gas mixtures. The LiPMIC is shown to have comparable efficiency to 3He proportional counters at a fraction of cost. Six-month long baseline measurements of overall detector performance shows there is a 3% reduction in total counts for 252Cf sources, which provides a good indicator for the longevity of the detector.

Chung, Kiwhan

2008-08-01T23:59:59.000Z

407

A new visible spectroscopy diagnostic for the JET ITER-like wall main chamber  

Science Conference Proceedings (OSTI)

In preparation for ITER, JET has been upgraded with a new ITER-like wall (ILW), whereby the main plasma facing components, previously of carbon, have been replaced by mainly Be in the main chamber and W in the divertor. As part of the many diagnostic enhancements, a new, survey, visible spectroscopy diagnostic has been installed for the characterization of the ILW. An array of eight lines-of-sight (LOS) view radially one of the two JET neutral beam shine through areas (W coated carbon fibre composite tiles) at the inner wall. In addition, one vertical LOS views the solid W tile at the outer divertor. The light emitted from the plasma is coupled to a series of compact overview spectrometers, with overall wavelength range of 380-960 nm and to one high resolution Echelle overview spectrometer covering the wavelength range 365-720 nm. The new survey diagnostic has been absolutely calibrated in situ by means of a radiometric light source placed inside the JET vessel in front of the whole optical path and operated by remote handling. The diagnostic is operated in every JET discharge, routinely monitoring photon fluxes from intrinsic and extrinsic impurities (e.g., Be, C, W, N, and Ne), molecules (e.g., BeD, D{sub 2}, ND) and main chamber and divertor recycling (typically D{alpha}, D{beta}, and D{gamma}). The paper presents a technical description of the diagnostic and first measurements during JET discharges.

Maggi, C. F. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, D-85748 Garching (Germany); Brezinsek, S. [Forschungszentrum Juelich GmbH, EURATOM Association, D-52425 Juelich (Germany); Stamp, M. F.; Griph, S.; Heesterman, P.; Hogben, C.; Horton, A.; Meigs, A.; Studholme, W.; Zastrow, K.-D. [EURATOM/CCFE, Fusion Association, Culham Science Centre, Abingdon, OX14 3DB (United Kingdom); Morlock, C. [EFDA-CSU Garching, Boltzmannstrasse 2, 85748 Garching (Germany); Collaboration: JET-EFDA Contributors

2012-10-15T23:59:59.000Z

408

CMS reconstruction improvement for the muon tracking by the RPC chambers  

E-Print Network (OSTI)

The contribution of Resistive Plate Chamber (RPC) to muon reconstruction in CMS has been studied on a sample of muons collected in proton-proton collisions at sqrt(s) = 7 TeV at the LHC in 2011. Muon reconstruction is performed using the all-silicon inner tracker and with up to four stations of gas-ionization muon detectors. Drift Tubes and Cathode Strip Chambers detect muons in the barrel and endcap regions, respectively, and are complemented by the RPC system. Measured distributions of reconstructed hits in the RPCs crossed by muons from Z decays with a transverse momentum pT above 20 GeV/c are well reproduced by the Monte Carlo simulation. From the samples of J/psi and Z events, the efficiencies for muons with and without the inclusion of the RPC hits in the muon track reconstruction are measured and compared with the simulation. Using RPC information in track reconstruction improves up to about 3% of offline reconstruction efficiency for the muons in the region of pT above 7 GeV/c, in good agreement with simulation.

Min Suk Kim on behalf of the CMS Collaboration

2012-09-12T23:59:59.000Z

409

Investigation of Micro Porosity Sintered wick in Vapor Chamber for Fan Less Design  

E-Print Network (OSTI)

Micro Porosity Sintered wick is made from metal injection molding processes, which provides a wick density with micro scale. It can keep more than 53 % working fluid inside the wick structure, and presents good pumping ability on working fluid transmission by fine infiltrated effect. Capillary pumping ability is the important factor in heat pipe design, and those general applications on wick structure are manufactured with groove type or screen type. Gravity affects capillary of these two types more than a sintered wick structure does, and mass heat transfer through vaporized working fluid determines the thermal performance of a vapor chamber. First of all, high density of porous wick supports high transmission ability of working fluid. The wick porosity is sintered in micro scale, which limits the bubble size while working fluid vaporizing on vapor section. Maximum heat transfer capacity increases dramatically as thermal resistance of wick decreases. This study on permeability design of wick structure is 0.5 - 0.7, especially permeability (R) = 0.5 can have the best performance, and its heat conductivity is 20 times to a heat pipe with diameter (Phi) = 10mm. Test data of this vapor chamber shows thermal performance increases over 33 %.

C. S. Yu; W. C. Wei; S. W. Kang

2008-01-07T23:59:59.000Z

410

Transition form factors of B decays into p-wave axial-vector mesons in the perturbative QCD approach  

Science Conference Proceedings (OSTI)

The B{sub u,d,s}{yields}V, A form factors are studied in the perturbative QCD approach (V, A denote a vector meson and two kinds of p-wave axial-vector mesons: {sup 3}P{sub 1} and {sup 1}P{sub 1} states, respectively). The form factors are directly studied in the large recoiling region and extrapolated to the whole kinematic region within the dipole parametrization. Adopting decay constants with different signs for the two kinds of axial vectors, we find that the two kinds of B{yields}A form factors have the same sign. The two strange mesons K{sub 1A} and K{sub 1B} mix with each other via the SU(3) symmetry breaking effect. In order to reduce the ambiguities in the mixing angle between K{sub 1A} and K{sub 1B}, we propose a model-independent way that utilizes the B decay data. Most of the branching fractions of the semilteptonic B{yields}Al{nu}{sub l} decays are of the order 10{sup -4}, which still need experimental tests in the ongoing and forthcoming experiments.

Li Rungui [Institute of High Energy Physics, P.O. Box 918(4) Beijing 100049 (China); School of Physics, Shandong University, Jinan 250100 (China); Lue Caidian [Institute of High Energy Physics, P.O. Box 918(4) Beijing 100049 (China); Kavli Institute for Theoretical Physics, Chinese Academy of Sciences, Beijing 100190 (China); Wang Wei [Institute of High Energy Physics, P.O. Box 918(4) Beijing 100049 (China)

2009-02-01T23:59:59.000Z

411

Exit blade geometry and part-load performance of small axial flow propeller turbines: An experimental investigation  

Science Conference Proceedings (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

412

Extraction of depth-dependent perturbation factors for parallel-plate chambers in electron beams using a plastic scintillation detector  

SciTech Connect

Purpose: This work presents the experimental extraction of the overall perturbation factor P{sub Q} in megavoltage electron beams for NACP-02 and Roos parallel-plate ionization chambers using a plastic scintillation detector (PSD). Methods: The authors used a single scanning PSD mounted on a high-precision scanning tank to measure depth-dose curves in 6, 12, and 18 MeV clinical electron beams. The authors also measured depth-dose curves using the NACP-02 and PTW Roos chambers. Results: The authors found that the perturbation factors for the NACP-02 and Roos chambers increased substantially with depth, especially for low-energy electron beams. The experimental results were in good agreement with the results of Monte Carlo simulations reported by other investigators. The authors also found that using an effective point of measurement (EPOM) placed inside the air cavity reduced the variation of perturbation factors with depth and that the optimal EPOM appears to be energy dependent. Conclusions: A PSD can be used to experimentally extract perturbation factors for ionization chambers. The dosimetry protocol recommendations indicating that the point of measurement be placed on the inside face of the front window appear to be incorrect for parallel-plate chambers and result in errors in the R{sub 50} of approximately 0.4 mm at 6 MeV, 1.0 mm at 12 MeV, and 1.2 mm at 18 MeV.

Lacroix, Frederic; Guillot, Mathieu; McEwen, Malcolm; Cojocaru, Claudiu; Gingras, Luc; Beddar, A. Sam; Beaulieu, Luc [Departement de Radio-Oncologie, Centre hospitalier de l'Universite de Montreal (CHUM), 1560 Sherbrooke Est, Montreal, Quebec H2L 4M1 (Canada) and Departement de Physique, Universite de Montreal, Pavillon Roger-Gaudry (D-428), 2900 Boul. Edouard-Montpetit, Montreal, Quebec H3T 1J4 (Canada); Departement de Physique, de Genie Physique et d'Optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada) and Departement de Radio-Oncologie, Ho circumflex tel-Dieu de Quebec, Centre hospitalier Universitaire de Quebec (CHUQ), Quebec, Quebec G1R 2J6 (Canada); Ionizing Radiation Standards, Institute for National Measurement Standards, National Research Council (NRC), Ottawa, Ontario K1A 0R6 (Canada); Departement de Physique, de Genie Physique et d'Optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada) and Departement de Radio-Oncologie, Ho circumflex tel-Dieu de Quebec, Centre hospitalier Universitaire de Quebec (CHUQ), Quebec, Quebec G1R 2J6 (Canada); Department of Radiation Physics, Unit 94, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030 (United States); Departement de Physique, de Genie Physique et d'Optique, Universite Laval, Quebec, Quebec G1K 7P4 (Canada) and Departement de Radio-Oncologie, Hotel-Dieu de Quebec, Centre hospitalier Universitaire de Quebec (CHUQ), Quebec, Quebec G1R 2J6 (Canada)

2010-08-15T23:59:59.000Z

413

U.S. Chamber of Commerce's 4th Annual North America Forum | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Commerce's 4th Annual North America Forum Commerce's 4th Annual North America Forum U.S. Chamber of Commerce's 4th Annual North America Forum June 16, 2008 - 1:30pm Addthis Remarks As Prepared for Delivery for Secretary Bodman Thank you very much, Ron, for that kind introduction and for the critically important work that you and your colleagues do at Lawrence Livermore. I also want to thank my good friend Secretary George Shultz - along with his esteemed co-chairs for this event, Peter Lougheed and Pedro Aspe, for inviting me to be with you. It's a pleasure to be here. The way I see it, this event could not come at a better time. With its focus on enhancing cooperation among the United States, Canada and Mexico - and on bringing together representatives of our governments and the private sector - you are helping to develop and achieve real and lasting solutions

414

Formation of metal nanoparticles by short-distance sputter deposition in a reactive ion etching chamber  

Science Conference Proceedings (OSTI)

A new method is reported to form metal nanoparticles by sputter deposition inside a reactive ion etching chamber with a very short target-substrate distance. The distribution and morphology of nanoparticles are found to be affected by the distance, the ion concentration, and the sputtering time. Densely distributed nanoparticles of various compositions were fabricated on the substrates that were kept at a distance of 130 mum or smaller from the target. When the distance was increased to 510 mum, island structures were formed, indicating the tendency to form continuous thin film with longer distance. The observed trend for nanoparticle formation is opposite to the previously reported mechanism for the formation of nanoparticles by sputtering. A new mechanism based on the seeding effect of the substrate is proposed to interpret the experimental results.

Nie Min; Meng, Dennis Desheng [Department of Mechanical Engineering and Engineering Mechanics, Michigan Technological University, Houghton, Michigan 49931 (United States); Sun Kai [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2009-09-01T23:59:59.000Z

415

Length and Straightness of the Tubes for the BOS Prototype Chamber  

E-Print Network (OSTI)

We have measured length and straightness of 50 tubes of 3.8~m length, after cleaning, wiring and testing from a batch that was used in the construction of the BOS prototype chamber. The specifi ed length (aluminum tube only, without endplug) was 3800~mm with a tolerance of $\\pm$1~mm. We found a mean value of (3805$\\pm$2)~mm with a standard deviation of (0.3$\\pm$0.1)~mm. The measureme nts of the straightness of the 50 BOS MDT tubes gave a mean of the maximum deviation of 150~$\\mu$m for 10 measured points along the tubes at 0$^{\\circ}$, 90$^{\\circ}$, 180$^{\\circ}$ and 270$^{\\circ }$ around the tube diameter and a mean value of all deviations of 20~$\\mu$m with a measuring accuracy of 10~$\\mu$m.

Lagouri, T

1998-01-01T23:59:59.000Z

416

Chamber Surface Roughness and Electron Cloud for the Advanced Photon Source Superconducting Undulator  

E-Print Network (OSTI)

The electron cloud is a possible heat source in the superconducting undulator (SCU) designed for the Advanced Photon Source (APS), a 7-GeV electron synchrotron radiation source at Argonne National Laboratory. In electron cloud generation extensive research has been done, and is continuing, to understand the secondary electron component. However, little work has been done to understand the parameters of photoemission in the accelerator environment. To better understand the primary electron generation in the APS; a beamline at the Australian Light Source synchrotron was used to characterize two samples of the Al APS vacuum chamber. The total photoelectron yield and the photoemission spectra were measured. Four parameters were varied: surface roughness, sample temperature, incident photon energy, and incident photon angle, with their results presented here.

Boon, Laura

2013-01-01T23:59:59.000Z

417

Analysis of Combustion Chamber Deposits by ESI-TOF-MS and MALDI-TOF-MS  

DOE Green Energy (OSTI)

Combustion chamber deposits (CCD) in internal combustion engines have been studied by various techniques to understand the relationship of performance degradation with deposit quantity and structure. XPS, XAS, NMR, and elemental analysis have offered insight into the bulk structure of C, H, N, O and metal components. MS has offered some information about compound structure, but results are limited due to the insolubility and complexity of the materials. Recently, we have reported on the metal structure by XPS and XAS of several deposits from a GM 3800 engine generated using a standard fuel and one that contains low levels of the gasoline anti-knock additive, MMT. Here we report the initial findings on the carbon structure of these deposits determined by ESI-TOF-MS and MADLI-TOF-MS.

Reynolds, J G; Shields, S J; Roos, J W

2001-06-14T23:59:59.000Z

418

Measurement of electrical properties of electrode materials for the bakelite Resistive Plate Chambers  

E-Print Network (OSTI)

Single gap (gas gap 2 mm) bakelite Resistive Plate Chamber (RPC) modules of various sizes from 10 cm \\times 10 cm to 1 m \\times 1 m have been fabricated, characterized and optimized for efficiency and time resolution. Thin layers of different grades of silicone compound are applied to the inner electrode surfaces to make them smooth and also to reduce the surface resistivity. In the silicone coated RPCs an efficiency > 90% and time resolution \\sim 2 ns (FWHM) have been obtained for both the streamer and the avalanche mode of operation. Before fabrication of detectors the electrical properties such as bulk resistivity and surface resistivity of the electrode materials are measured carefully. Effectiveness of different silicone coating in modifying the surface resistivity was evaluated by an instrument developed for monitoring the I-V curve of a high resistive surface. The results indicate definite correlation of the detector efficiency for the atmospheric muons and the RPC noise rates with the surface resistiv...

Meghna, K K; Biswas, S; Bhattacharya, S; Bose, S; Chattopadhyay, S; Das, G; Marick, C; Saha, S; Viyogi, Y P

2012-01-01T23:59:59.000Z

419

SEY and Surface Analysis Measurements on FNAL Main Injector Ring S/S Beam Chamber Material  

DOE Green Energy (OSTI)

Material was provided by Dr. Weiren Chou, FNAL. Both mildly-activated used, and new sections of stainless steel (type 316L) beam chamber were measured. Centimeter-sized coupons were cleanly dry-cut from the large flat surface (called ''flat side'' in the plots) and from the ID end (inside diameter of the ring, in the case of the used material) and narrow end (in the case of the new material). The unused material was ultra-soniced in acetone (to remove storage residue), then rinsed with ethanol and blown dry with filtered N{sub 2}-gas, to simulate new chamber installation final rinse. Used material was installed, as cut. Surface chemistry was measured using x-ray photoelectron spectroscopy (sometimes called ''ESCA''). With this technique, soft x-rays (1486 eV) illuminate the sample, penetrating into the surface ten microns. Photoelectrons are generated from energy levels of the constituent compounds/elements present. Those electrons, within 5 nm or so of the surface, escape without energy loss and preserve valence information about the atomic levels from which they were generated. An electron energy analyzer, of good energy resolution, measures the photoelectron energy, thereby yielding both valence (chemical) information and relative atomic abundances in the top 5 nm of surface. Using appropriate sensitivity factors, these intensities are converted to a semi-quantitative (surface atom %) concentration in the analyzed layer. As a benchmark, the limit for carbon contamination on vacuum components for UHV use at SLAC is 50 at%. That corresponds to about 8-10 monolayers of elemental carbon. XPS does not detect hydrogen because it has no electrons after bonding. Generally, hydrides do not show evidence of ''chemical shift'' of the binding energy of the metal lines.

Kirby, Robert E.; /SLAC

2006-09-18T23:59:59.000Z

420

Usiing NovoCOS cleaning equipment in repairing the furnace-chamber lining in coke batteries 4 & 5 at OAO Koks  

SciTech Connect

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

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

Imprints of the nuclear symmetry energy on gravitational waves from the axial w-modes of neutron stars  

E-Print Network (OSTI)

The eigen-frequencies of the axial w-modes of oscillating neutron stars are studied using the continued fraction method with an Equation of State (EOS) partially constrained by the recent terrestrial nuclear laboratory data. It is shown that the density dependence of the nuclear symmetry energy $E_{sym}(\\rho)$ affects significantly both the frequencies and the damping times of these modes. Besides confirming the previously found universal behavior of the mass-scaled eigen-frequencies as functions of the compactness of neutron stars, we explored several alternative universal scaling functions. Moreover, the $w_{II}$-mode is found to exist only for neutron stars having a compactness of $M/R\\geq 0.1078$ independent of the EOS used.

De-Hua Wen; Bao-An Li; Plamen G. Krastev

2009-02-26T23:59:59.000Z

422

Exact analysis of particle dynamics in combined field of finite duration laser pulse and static axial magnetic field  

Science Conference Proceedings (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

423

Computerized axial tomography of the chest for visualization of ''absent'' pulmonary arteries  

SciTech Connect

To expand the search for central pulmonary arteries in six patients with absence of cardiac-pulmonary continuity, computerized axial tomography (CAT) of the chest was performed. The CAT scans were compared with previous arteriograms and pulmonary vein wedge angiograms. Three patients with type IV truncus arteriosus were studied, and none had a central, right or left pulmonary artery on CAT scan. However, two patients with tetralogy of Fallot with pulmonary atresia and a patent ductus arteriosus to the right lung demonstrated the presence of a left pulmonary artery. In addition, one child with truncus arteriosus with ''absent'' left pulmonary artery demonstrated a left pulmonary artery on the CAT scan. The CAT scan may therefore enhance our ability to search for disconnected pulmonary arteries in children with complex cyanotic congenital heart disease.

Sondheimer, H.M. (Upstate Medical Center, Syracuse, NY); Oliphant, M.; Schneider, B.; Kavey, R.E.W.; Blackman, M.S.; Parker, F.B. Jr.

1982-05-01T23:59:59.000Z

424

A Study of Homogeneous Condensation-Freezing Nucleation of Small Water Droplets in an Expansion Cloud Chamber  

Science Conference Proceedings (OSTI)

Observations of the homogeneous nucleation of water vapor in an expansion cloud chamber have been carried out for the temperature range ?50 to +17C in the carrier gases argon and helium. We have found that the onset of the ice phase in freshly ...

Rodney J. Anderson; Ronald C. Miller; James L. Kassner Jr.; Donald E. Hagen

1980-11-01T23:59:59.000Z

425

Large-eddy simulations of air flow and turbulence within and around low aspect ratio cylindrical open-top chambers  

Science Conference Proceedings (OSTI)

The flow around cylindrical open-top chambers (OTCs) with aspect ratios (i.e., height-to-diameter ratios) much less than unity is investigated using a large-eddy simulation (LES) model. The solid structures are represented using the immersed ...

Philip Cunningham; Rodman R. Linn; Eunmo Koo; Cathy J. Wilson

426

Tests of Micro-Pattern Gaseous Detectors for Active1 Target Time Projection Chambers in nuclear physics2  

E-Print Network (OSTI)

Tests of Micro-Pattern Gaseous Detectors for Active1 Target Time Projection Chambers in nuclear the gas used as the detection medium10 is also a target for nuclear reactions, have been used for a wide variety of11 nuclear physics applications since the eighties. Improvements in MPGD (Mi-12 cro Pattern

Recanati, Catherine

427

EFFECT OF NEUTRON IRRADIATION ON MATERIALS SUBJECTED TO MULTI-AXIAL STRESS DISTRIBUTIONS. Quarterly Report for the Period Ending June 30, 1962  

SciTech Connect

Activities in a program to determine the effects of neutron irradiation on A-302B steel are reported. Plans are discussed concerning performance tests on tensile, notched tensile, tube, and Charpy specimens. An irradiation capsule design was finalized. A theoretical analysis of the critical conditions arising in a tube subjected to both internal pressure and axial load is included. (J.R.D.)

Trozera, T A

1962-08-13T23:59:59.000Z

428

The Effect of Oxygen to Methane Ratio on the Methane-wet Air Autothermal Reforming and Carbon Deposition in the Micro-chamber  

Science Conference Proceedings (OSTI)

Considering the problems of catalyst carbon deposition and reforming endothermic reaction in micro-reforming chamber, coupled methane catalyst partial oxidation and steam methane reforming can make the micro-reforming system auto-supply heat and inhibit ... Keywords: micro-chamber, autothermal reforming, carbon deposition, oxygen to methane ratio

Ran Jingyu; Tu Weifeng

2011-01-01T23:59:59.000Z

429

Advanced radiation techniques for inspection of diesel engine combustion chamber materials components. Final report  

DOE Green Energy (OSTI)

Heavy duty truck engines must meet stringent life cycle cost and regulatory requirements. Meeting these requirements has resulted in convergence on 4-stroke 6-in-line, turbocharged, and after-cooled engines with direct-injection combustion systems. These engines provide much higher efficiencies (42%, fuel consumption 200 g/kW-hr) than automotive engines (31%, fuel consumption 270 g/kW-hr), but at higher initial cost. Significant near-term diesel engine improvements are necessary and are spurred by continuing competitive, Middle - East oil problems and Congressional legislation. As a result of these trends and pressures, Caterpillar has been actively pursuing a low-fuel consumption engine research program with emphasis on product quality through process control and product inspection. The goal of this project is to combine the nondestructive evaluation and computational resources and expertise available at LLNL with the diesel engine and manufacturing expertise of the Caterpillar Corporation to develop in-process monitoring and inspection techniques for diesel engine combustion chamber components and materials. Early development of these techniques will assure the optimization of the manufacturing process by design/inspection interface. The transition from the development stage to the manufacturing stage requires a both a thorough understanding of the processes and a way of verifying conformance to process standards. NDE is one of the essential tools in accomplishing both elements and in this project will be integrated with Caterpillar`s technological and manufacturing expertise to accomplish the project goals.

NONE

1995-10-09T23:59:59.000Z

430

Performance of a Drift Chamber Candidate for a Cosmic Muon Tomography System  

SciTech Connect

In the last decade, many groups around the world have been exploring different ways to probe transport containers which may contain illicit Special Nuclear Materials such as uranium. The muon tomography technique has been proposed as a cost effective system with an acceptable accuracy. A group of Canadian institutions (see above), funded by Defence Research and Development Canada, is testing different technologies to track the cosmic muons. One candidate is the single wire Drift Chamber. With the capability of a 2D impact position measurement, two detectors will be placed above and two below the object to be probed. In order to achieve a good 3D image quality of the cargo content, a good angular resolution is required. The simulation showed that 1mrad was required implying the spatial resolution of the trackers must be in the range of 1 to 2 mm for 1 m separation. A tracking system using three prototypes has been built and tested. The spatial resolution obtained is 1.7 mm perpendicular to the wire and 3 mm along the wire.

Anghel, V.; Jewett, C.; Jonkmans, G.; Thompson, M. [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada); Armitage, J.; Botte, J.; Boudjemline, K.; Erlandson, A.; Oakham, G. [Ottawa-Carleton Institute for Physics, Department of Physics, Carleton University, Ottawa, Ontario (Canada); Bueno, J.; Bryman, D.; Liu, Z. [Advanced Applied Physics Solutions, Vancouver, British Columbia (Canada); Charles, E.; Gallant, G. [Canada Border Services Agency, Ottawa, Ontario (Canada); Cousins, T.; Noel, S. [International Safety Research, Ottawa, Ontario (Canada); Drouin, P.-L.; Waller, D. [Defence Research and Development Canada, Ottawa, Ontario (Canada); Stocki, T. J. [Health Canada, Ottawa, Ontario (Canada)

2011-12-13T23:59:59.000Z

431

Computerized axial tomography: technology and equipment. January, 1977-May, 1981 (Citations from the International Information Service for the Physics and Engineering Communities data base). Report for January 1977-May 1981  

SciTech Connect

This retrospective bibliography contains citations concerning many recent developments in the instrumentation, technology, and application of computerized axial tomography (CAT). Production model CAT scanners are compared and evaluated for noise, spatial resolution, axial position sensitivity, artefact and dose. Research and development on new scanners are considered. (Contains 71 citations fully indexed and including a title list.)

1981-05-01T23:59:59.000Z

432

Observations of Secondary Organic Aerosol Production and Soot Aging under Atmospheric Conditions Using a Novel Environmental Aerosol Chamber  

E-Print Network (OSTI)

Secondary organic aerosols (SOA) comprise a substantial fraction of the total global aerosol budget. While laboratory studies involving smog chambers have advanced our understanding of the formation mechanisms responsible for SOA, our knowledge of the processes leading to SOA production under ambient gaseous and particulate concentrations as well as the impact these aerosol types have on climate is poorly understood. Although the majority of atmospheric aerosols scatter radiation either directly or indirectly by serving as cloud condensation nuclei, soot is thought to have a significant warming effect through absorption. Like inorganic salts, soot may undergo atmospheric transformation through the vapor condensation of non-volatile gaseous species which will alter both its chemical and physical properties. Typical smog chamber studies investigating the formation and growth of SOA as well as the soot aging process are temporally limited by the initial gaseous concentrations injected into the chamber environment. Furthermore, data interpretation from such experiments is generally restricted to the singular gaseous species under investigation. This dissertation discusses the use of a new aerosol chamber designed to study the formation and growth of SOA and soot aging under atmospherically relevant conditions. The Ambient Aerosol Chamber for Evolution Studies (AACES) was deployed at three field sites where size and hygroscopic growth factor (HGF) of ammonium sulfate seed particles was monitored over time to examine the formation and growth of SOA. Similar studies investigating the soot aging process were also conducted in Houston, TX. It is shown that during the ambient growth of ammonium sulfate seed particles, as particle size increases, hygroscopic growth factors decrease considerably resulting in a significant organic mass fraction in the particle phase concluding an experiment. Observations of soot aging show an increase in measured size, HGF, mass and single scattering albedo. Ambient growth rate comparisons with chamber growth yielded similar trends verifying the use of AACES to study aerosol aging. Based on the results from this study, it is recommended that AACES be employed in future studies involving the production and growth of SOA and soot aging under ambient conditions in order to bridge the gaps in our current scientific knowledge.

Glen, Crystal

2010-12-01T23:59:59.000Z

433

Ginzburg-Landau phase diagram for dense matter with axial anomaly, strange quark mass, and meson condensation  

SciTech Connect

We discuss the phase structure of dense matter, in particular, the nature of the transition between hadronic and quark matter. Calculations within a Ginzburg-Landau approach show that the axial anomaly can induce a critical point in this transition region. This is possible because in three-flavor quark matter with instanton effects a chiral condensate can be added to the color-flavor locked phase without changing the symmetries of the ground state. In (massless) two-flavor quark matter such a critical point is not possible since the corresponding color superconductor (2SC) does not break chiral symmetry. We study the effects of a nonzero but finite strange quark mass which interpolates between these two cases. Since at ultrahigh density the first reaction of the color-flavor locked phase to a nonzero strange quark mass is to develop a kaon condensate, we extend previous Ginzburg-Landau studies by including such a condensate. We discuss the fate of the critical point systematically and show that the continuity between hadronic and quark matter can be disrupted by the onset of a kaon condensate. Moreover, we identify the mass terms in the Ginzburg-Landau potential which are needed for the 2SC phase to occur in the phase diagram.

Schmitt, Andreas; Stetina, Stephan [Institut fuer Theoretische Physik, Technische Universitaet Wien, 1040 Vienna (Austria); Tachibana, Motoi [Department of Physics, Saga University, Saga 840-8502 (Japan)

2011-02-15T23:59:59.000Z

434

Axial-flux modular permanent-magnet generator with a toroidal winding for wind-turbine applications  

SciTech Connect

Permanent-magnet (PM) generators have been used for wind turbines for many years. Many small wind-turbine manufacturers use direct-drive PM generators. For wind-turbine generators, the design philosophy must cover the following characteristics: low cost, light weight, low speed, high torque, and variable-speed generation. The generator is easy to manufacture and the design can be scaled up for a larger size without major retooling. A modular PM generator with axial flux direction was chosen. The permanent magnet used is NdFeB or ferrite magnet with flux guide to focus flux density in the air gap. Each unit module of the generator may consist of one, two, or more phases. Each generator can be expanded to two or more unit modules. Each unit module is built from simple modular poles. The stator winding is formed like a torus. Thus, the assembly process is simplified and the winding insertion in the slot is less tedious. The authors built a prototype of one unit module and performed preliminary tests in the laboratory. Follow-up tests will be conducted in the laboratory to improve the design.

Muljadi, E.; Butterfield, C.P.; Wan, Y.H.

1999-08-01T23:59:59.000Z

435

Hydrocarbon-fuel/combustion-chamber-liner materials compatibility. Interim final report, 7 November 1986-31 October 1989  

SciTech Connect

Results of material compatibility experiments using hydrocarbon fuels in contact with copper-based combustion chamber liner materials are presented. Mil-Spec RP-1, n- dodecane, propane, and methane fuels were tested in contact with OFHC, NASA-Z, and ZrCu coppers. Two distinct test methods were employed. Static tests, in which copper coupons were exposed to fuel for long durations at constant temperature and pressure, provided compatibility data in a precisely controlled environment. Dynamic tests, using the Aerojet Carbothermal Test Facility, provided fuel and copper compatibility data under realistic booster engine service conditions. Tests were conducted using very pure grades of each fuel and fuels to which a contaminant, e.g., ethylene or methyl mercaptan, was added to define the role played by fuel impurities. Conclusions are reached as to degradation mechanisms and effects, methods for the elimination of these mechanisms, selection of copper alloy combustion chamber liners, and hydrocarbon fuel purchase specifications.

Gage, M.L.

1990-04-01T23:59:59.000Z

436

Forward Drift Chamber for the GlueX Experiment at the 12 GeV CEBAF Machine  

Science Conference Proceedings (OSTI)

The GlueX experiment will search for exotic mesons produced by 9 GeV linearly polarized photons from the upgraded CEBAF machine. It is critical to detect and measure the four-momenta of all the charged particles and photons resulting from the decays of the mesons. The solenoid-based detector system includes tracking detectors and calorimeters. The Forward Drift Chamber, FDC, consists of 24 circular planar drift chambers of 1m diameter. Additional cathode readout is required to achieve efficient pattern recognition. The detection of photons by the electromagnetic calorimeters imposes constraints on the amount of material used in the FDC. The specific features of the detector and the readout electronics will be described. Results from the tests of the full scale prototype will be presented, as well.

Pentchev, Lubomir; Zihlmann, Benedikt [Thomas Jefferson National Accelerator Facility, 12000 Jefferson Ave., Newport News, VA 23606 (United States)

2011-06-01T23:59:59.000Z

437

Forward Drift Chamber for the GlueX experiment at the 12 GeV CEBAF machine  

Science Conference Proceedings (OSTI)

The GlueX experiment will search for exotic mesons produced by 9 GeV linearly polarized photons from the upgraded CEBAF machine. It is critical to detect and measure the four-momenta of all the charged particles and photons resulting from the decays of the mesons. The solenoid-based detector system includes tracking detectors and calorimeters. The Forward Drift Chamber, FDC, consists of 24 circular planar drift chambers of 1m diameter. Additional cathode readout is required to achieve efficient pattern recognition. The detection of low energy photons by the electromagnetic calorimeters imposes constraints on the amount of material used in the FDC. The specific features of the detector and the readout electronics will be described. Results from the tests of the full scale prototype will be presented, as well.

Lubomir Pentchev, Benedikt Zihlmann

2011-06-01T23:59:59.000Z

438

A Measurement of the holographic minimum observable beam branching ratio in the Fermilab 15-foot bubble chamber  

SciTech Connect

Holography has been used successfully in combination with conventional optics for the first time in a large cryogenic bubble chamber, the 15-Foot Bubble Chamber at Fermilab, during a physics run. The innovative system combined the reference beam with the object beam, illuminating a conical volume of {approx} 1.4 m{sup 3}. Bubble tracks from neutrino interactions with a width of {approx} 120 {micro}m have been recorded with good contrast. The ratio of intensities of the object light to the reference light striking the film is called the Beam Branching Ratio. We obtained in our experiment an exceedingly small minimum-observable ratio of (0.54 {+-} 0.21) x 10{sup -7}. The technology has the potential for a wide range of applications.

Aderholz, M.; Aggarwal, M.M.; Akbari, H.; Allport, P.P.; Badyal, S.K.; Ballagh, H.C.; Barth, M.; Baton, J.P.; Bingham, H.H.; Bjelkhagen, H.; Brucker, E.B.; Burnstein, R.A.; Campbell, J.R.; Cence, R.J.; Chatterjee, T.K.; Clayton, E.F.; Corrigan, G.; Coutures, C.; DeProspo, D.; Devanand,; De Wolf, E.A.; /UC, Berkeley /Birmingham U. /Brussels U., IIHE /CERN /Punjab U. /Fermilab /Hawaii U. /Imperial Coll., London /IIT, Chicago /Jammu U. /Munich, Max Planck Inst. /Oxford U. /Rutgers U., Piscataway /Rutherford /DAPNIA, Saclay /Stevens Tech. /Tufts U.

1997-01-01T23:59:59.000Z

439

Scintillation counter and wire chamber front end modules for high energy physics experiments  

SciTech Connect

This document describes two front-end modules developed for the proposed MIPP upgrade (P-960) experiment at Fermilab. The scintillation counter module was developed for the Plastic Ball detector time and charge measurements. The module has eight LEMO 00 input connectors terminated with 50 ohms and accepts negative photomultiplier signals in the range 0.25...1000 pC with the maximum input voltage of 4.0 V. Each input has a passive splitter with integration and differentiation times of {approx}20 ns. The integrated portion of the signal is digitized at 26.55 MHz by Analog Devices AD9229 12-bit pipelined 4-channel ADC. The differentiated signal is discriminated for time measurement and sent to one of the four TMC304 inputs. The 4-channel TMC304 chip allows high precision time measurement of rising and falling edges with {approx}100 ps resolution and has internal digital pipeline. The ADC data is also pipelined which allows deadtime-less operation with trigger decision times of {approx}4 {micro}s. The wire chamber module was developed for MIPP EMCal detector charge measurements. The 32-channel digitizer accepts differential analog signals from four 8-channel integrating wire amplifiers. The connection between wire amplifier and digitizer is provided via 26-wire twist-n-flat cable. The wire amplifier integrates input wire current and has sensitivity of 275 mV/pC and the noise level of {approx}0.013 pC. The digitizer uses the same 12-bit AD9229 ADC chip as the scintillator counter module. The wire amplifier has a built-in test pulser with a mask register to provide testing of the individual channels. Both modules are implemented as a 6Ux220 mm VME size board with 48-pin power connector. A custom europack (VME) 21-slot crate is developed for housing these front-end modules.

Baldin, Boris; DalMonte, Lou; /Fermilab

2011-01-01T23:59:59.000Z

440

EDDY CURRENT EFFECT OF THE BNL-AGS VACUUM CHAMBER ON THE OPTICS OF THE BNL-AGS SYNCHROTRON.  

Science Conference Proceedings (OSTI)

During the acceleration cycle of the AGS synchrotron, eddy currents are generated within the walls of the vacuum chambers of the AGS main magnets. The vacuum chambers have elliptical cross section, are made of inconel material with a wall thickness of 2 mm and are placed within the gap of the combined-function main magnets of the AGS synchrotron. The generation of the eddy currents in the walls of the vacuum chambers, creates various magnetic multipoles, which affect the optics of the AGS machine. In this report these magnetic multipoles are calculated for various time interval starting at the acceleration cycle, where the magnetic field of the main magnet is {approx}0.1 T, and ending before the beam extraction process, where the magnetic field of the main magnet is almost constant at {approx}1.1 T. The calculations show that the magnetic multipoles generated by the eddy-currents affect the optics of the AGS synchrotron during the acceleration cycle and in particular at low magnetic fields of the main magnet. Their effect is too weak to affect the optics of the AGS machine during beam extraction at the nominal energies.

TSOUPAS,N.; AHRENS,L.; BROWN,K.A.; GLENN,J.W.; GARDNER,K.

1999-03-29T23:59:59.000Z

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.


441

Technological cost%3CU%2B2010%3Ereduction pathways for axial%3CU%2B2010%3Eflow turbines in the marine hydrokinetic environment.  

SciTech Connect

This report considers and prioritizes potential technical costreduction pathways for axialflow turbines designed for tidal, river, and ocean current resources. This report focuses on technical research and development costreduction pathways related to the device technology rather than environmental monitoring or permitting opportunities. Three sources of information were utilized to understand current cost drivers and develop a list of potential costreduction pathways: a literature review of technical work related to axialflow turbines, the U.S. Department of Energy Reference Model effort, and informal webinars and other targeted interactions with industry developers. Data from these various information sources were aggregated and prioritized with respect to potential impact on the lifetime levelized cost of energy. The four most promising costreduction pathways include structural design optimization; improved deployment, maintenance, and recovery; system simplicity and reliability; and array optimization.

Laird, Daniel L.; Johnson, Erick L.; Ochs, Margaret Ellen; Boren, Blake [Oregon State University, Corvallis, OR

2013-05-01T23:59:59.000Z

442

FE Magnetic Field Analysis Simulation Models based Design, Development, Control and Testing of An Axial Flux Permanent Magnet Linear Oscillating Motor  

E-Print Network (OSTI)

Abstract- Development, finite element(FE) analysis of magnetic field distribution, performance, control and testing of a new axial flux permanent magnet linear oscillating motor (PMLOM) along with a suitable speed and thrust control technique is described in this paper. The PMLOM can perform precision oscillation task without exceeding the given limit on allowable average power dissipation. The use of new powerful permanent magnet materials such as Neodymium-Iron-Boron alloys can greatly improve the performance of electrical machines. Also its performance parameters, such as the force, current etc. are experimentally assessed. The objective of this paper is to determine the forces for aluminium mover embedded with rare earth permanent magnet experimentally and analytically through FEMM software and develop a microcontroller based IGBT Inverter for its control. Index Terms- Axial flux machine, finite element analysis, microcontroller based IGBT inverter, permanent magnet linear oscillating motor, rare earth permanent magnet. I.

Govindaraj T; Prof Dr; Ashoke K. Ganguli

2009-01-01T23:59:59.000Z

443

The Influence of Blank-Width Ratio on Stress Field during Heavy Axial Forgings Manufacturing with Horizontal V-Shaped Anvils  

Science Conference Proceedings (OSTI)

The forging method with horizontal V-shaped anvils (HVA) is effective in the control of inner stress states, metal tissue, etc. FEM numerical simulation is conducted for the HVA forging method, given the blank-width ratio 0.5, 1.0 and 1.2, respectively, ... Keywords: horizontal V-shaped anvil, anvil-width ratio, blank-width ratio, axial forging, stress field

Li Li; Wang Qian; Yu Suoqing; Ni Liyong

2010-01-01T23:59:59.000Z

444

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

E-Print Network (OSTI)

Bloodmeal host preferences were assessed for Culex salinarius populations occurring along the upper Gulf Coast region of East Texas. Over a one-year period beginning in September 1991, blood-engorged female Cx. salinarius specimens were collected 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 sampled at each site. No noticeable changes in bloodmeal host preferences occurred for Cx. salinarius populations sampled at the coastal marsh site during the study period. Mammals were the primary sources of bloodmeals for these populations, with most mosquitoes collected having fed on cattle. There was an increase in specimens testing positive for avian blood during winter (Dec.-Feb.) commensurate with the arrival of migratory goose populations in the vicinity. The overall foraging ratio, however, did not change. Culex salinarius populations sampled at the upper marsh site also demonstrated a preference for mammalian blood throughout the year. However, forage ratios indicated these populations varied in the mammals upon which they fed, with a number of specimens having fed on armadillos. Cx. salinarius populations sampled at the up-county site demonstrated greater tendency to select birds as bloodmeal sources. Mosquito specimens at this site tested positive for either passeriiform or ciconiiform birds, with a few specimens testing positive for rabbits and cattle. A preference was shown for ciconiiform birds during the spring (March-May). During the rest of the year, passeriiform birds served more as a source of bloodmeals for Cx. salinarius populations. Forage ratios indicated the use of passeriiform birds was not a function of preference, but rather a result of these birds being abundant at the up-county site. Results of this study substantiate earlier findings that Cx. salinarius females will use both mammals and birds as sources of bloodmeals. Females of this species are generalistic feeders and will utilize hosts that are in greatest abundance or which require the least amount of energy on the part of the mosquito to acquire.

Grieco, John Paul

1994-01-01T23:59:59.000Z

445

Toward an In Vitro Vasculature: Differentiation of Mesenchymal Stromal Cells Within an Endothelial Cell-Seeded Modular Construct in a Microfluidic Flow Chamber  

E-Print Network (OSTI)

An in vitro tissue construct amenable to perfusion was formed by randomly packing mesenchymal stromal cell (MSC)-embedded, endothelial cell (EC)-coated collagen cylinders (modules) into a microfluidic chamber. The interstices ...

Chamberlain, M. Dean

446

The Segregation of Aerosols by Cloud-Nucleating Activity. Part I: Design, Construction, and Testing of A High-Flux Thermal Diffusion Cloud Chamber for Mass Separation  

Science Conference Proceedings (OSTI)

We describe a thermal diffusion cloud chamber operated in series with an aerodynamic dichotomous separator that can segregate aerosol particles by their abilities to nucleate cloud droplets. The apparatus takes advantage of compensating gradients ...

Lee Harrison; Halstead Harrison

1985-04-01T23:59:59.000Z

447

Photon stimulated desorption (PSD) measurements of extruded copper and of welded copper beam chambers for the PEP II asymmetric B-factory  

DOE Green Energy (OSTI)

PEP II is being built as a higher luminosity electron-positron collider, with asymmetric beams of 9 GeV and 3.1 GeV, having maximum currents of 3.0 A. Based on the previous work on the NSLS VUV beamline U10B, a copper was selected for construction of UHV beam chambers and absorbers to minimize the pressure rise from synchrotron radiation during operation. An extruded beam chamber and a welded beam chamber were fabricated from the selected copper for PSD measurements on NSLS X-ray beamline X28A. The chambers were exposed to white light with a critical energy of 5 KeV, both direct and through a 0.010 inch thick Beryllium filter. Each chamber was exposed to a dose of approximately 10{sup 23} photons per meter at an incidence angle of 25 mrad, after argon glow conditioning and a 150 C vacuum bake. Desorption yields for H{sub 2} CO, CO{sub 2}, and CH{sub 4} are reported as a function of accumulated photon flux, critical energy, and chamber preparation. The results are compared with the previous work on beamline U10B and with those of other published work for copper.

Foerster, C.L.; Lanni, C. [Brookhaven National Lab., Upton, NY (United States). NSLS; Perkins, C. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Calderon, M.; Barletta, W. [Lawrence Livermore National Lab., CA (United States)

1994-12-31T23:59:59.000Z

448

Cl atom recombination on silicon oxy-chloride layers deposited on chamber walls in chlorine-oxygen plasmas  

SciTech Connect

Chlorine atom recombination coefficients were measured on silicon oxy-chloride surfaces deposited in a chlorine inductively coupled plasma (ICP) with varying oxygen concentrations, using the spinning wall technique. A small cylinder embedded in the walls of the plasma reactor chamber was rapidly rotated, repetitively exposing its surface to the plasma chamber and a differentially pumped analysis chamber housing a quadruple mass spectrometer for line-of-sight desorbing species detection, or an Auger electron spectrometer for in situ surface analysis. The spinning wall frequency was varied from 800 to 30 000 rpm resulting in a detection time, t (the time a point on the surface takes to rotate from plasma chamber to the position facing the mass or Auger spectrometer), of {approx}1-40 ms. Desorbing Cl{sub 2}, due to Langmuir-Hinshelwood (LH) Cl atom recombination on the reactor wall surfaces, was detected by the mass spectrometer and also by a pressure rise in one of the differentially pumped chambers. LH Cl recombination coefficients were calculated by extrapolating time-resolved desorption decay curves to t = 0. A silicon-covered electrode immersed in the plasma was either powered at 13 MHz, creating a dc bias of -119 V, or allowed to electrically float with no bias power. After long exposure to a Cl{sub 2} ICP without substrate bias, slow etching of the Si wafer coats the chamber and spinning wall surfaces with an Si-chloride layer with a relatively small amount of oxygen (due to a slow erosion of the quartz discharge tube) with a stoichiometry of Si:O:Cl = 1:0.38:0.38. On this low-oxygen-coverage surface, any Cl{sub 2} desorption after LH recombination of Cl was below the detection limit. Adding 5% O{sub 2} to the Cl{sub 2} feed gas stopped etching of the Si wafer (with no rf bias) and increased the oxygen content of the wall deposits, while decreasing the Cl content (Si:O:Cl = 1:1.09:0.08). Cl{sub 2} desorption was detectable for Cl recombination on the spinning wall surface coated with this layer, and a recombination probability of {gamma}{sub Cl} = 0.03 was obtained. After this surface was conditioned with a pure oxygen plasma for {approx}60 min, {gamma}{sub Cl} increased to 0.044 and the surface layer was slightly enriched in oxygen fraction (Si:O:Cl = 1:1.09:0.04). This behavior is attributed to a mechanism whereby Cl LH recombination occurs mainly on chlorinated oxygen sites on the silicon oxy-chloride surface, because of the weak Cl-O bond compared to the Cl-Si bond.

Khare, Rohit; Srivastava, Ashutosh; Donnelly, Vincent M. [Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas 77204 (United States)

2012-09-15T23:59:59.000Z

449

Turbulent particle deposition in a rectangular chamber: Study of the effect of particle size and ventilation regimes  

SciTech Connect

The interaction of aerosol particles with wall surfaces is important in modeling their behavior. This interaction is usually represented in theoretical models as a loss term. The loss rate is the rate at which particles deposit or react with the surfaces. This loss term is important in many branches of aerosol science including human health and indoor air quality. Increased surface deposition usually means lower concentrations of airborne particles and hence, lower exposure to the inhabitants. If the efficiency of the particle deposition is influenced by factors other than the particle size, such as a natural convection of the air, this has to be taken into account to evaluate the results. In this research, test aerosol sized from 15 nm to 3 {micro}m are produced by several different aerosol generators; the gas burner, the Collison nebulizer, the condensation aerosol generator, the orifice atomizer and the Vibrating Orifice Aerosol Generator (VOAG). A rectangular chamber whose dimensions are 75 x 75 x 180 cm{sup 3} was used in this study. The particles were injected into the chamber, with a known ventilation and the concentration decay was monitored by the Ultrafine Condensation Particle Counter (UCPC) and Optical Particle Counter (OPC). During the measurement, the air inside the chamber is moved by natural convection and ventilation effect. The results shows that the particle loss rate under the higher air exchange rate is larger and this is not only due to air exchange itself but also the wall deposition. The theoretical model presented by Benes and Holub (1996) agree with the experimental data better than the Crump and Seinfield (1981) model with the hypothesis of Plandtl`s mixing length. 118 refs.

Nomura, Yoshio

1996-04-01T23:59:59.000Z

450

Second coordinate readout in drift chambers by timing of the electromagnetic wave propagating along the anode wire  

Science Conference Proceedings (OSTI)

The feasibility of using an anode wire and surrounding electrodes in drift chambers as a transmission line for second coordinate readout has been studied. The method is based on propagation of the electromagnetic wave along the anode wire is determined by measurement, in an optimized electronic readout system, of the time difference between the arrivals of the signal to the ends of the wire. The resolution obtained on long wires (approx. 2 meters) is about 2 cm FWHM for minimum ionizing particles at a gas gain of approx. = 10/sup 5/.

Boie, R.A.; Radeka, V.; Rehak, P.; Xi, D.M.

1980-11-01T23:59:59.000Z

451

Test and evaluation of the Argonne BPAC10 Series air chamber calorimeter designed for 20 minute measurements  

SciTech Connect

This paper is the final report on DOE-OSS Task ANLE88002 Fast Air Chamber Calorimetry.'' The task objective was to design, construct, and test an isothermal air chamber calorimeter for plutonium assay of bulk samples that would meet the following requirements for sample power measurement: average sample measurement time less than 20 minutes. Measurement of samples with power output up to 10 W. Precision of better than 1% RSD for sample power greater than 1 W. Precision better than 0.010 watt SD, for sample power less than 1 W. This report gives a description of the calorimeter hardware and software and discusses the test results. The instrument operating procedure, included as an appendix, gives examples of typical input/output and explains the menu driven software. Sample measurement time of less than 20 minutes was attained by pre-equilibration of the samples in low cost precision preheaters and by prediction of equilibrium measurements. Tests at the TA55 Plutonium Facility at Los Alamos National Laboratory, on typical samples, indicates that the instrument meets all the measurement requirements.

Perry, R.B.; Fiarman, S.; Jung, E.A. (Argonne National Lab., IL (USA)); Cremers, T. (Los Alamos National Lab., NM (USA))

1990-10-01T23:59:59.000Z

452

Characterization and performances of a monitoring ionization chamber dedicated to IBA-universal irradiation head for Pencil Beam Scanning  

E-Print Network (OSTI)

Every radiotherapy center has to be equipped with real-time beam monitoring devices. In 2008, the medical application group from the Laboratory of Corpuscular Physics (LPC Caen) developed an Ionization Chamber in collaboration with the company IBA (Ion Beam Applications). This monitoring device called IC2/3 was developed to be used in IBAs universal irradiation head for Pencil Beam Scanning (PBS). The objectives presented in this article are to characterize the IC2/3 monitor in the energy and ux ranges used in protontherapy. The equipment has been tested with an IBAs cyclotronable to deliver proton beams from 70 to 230 MeV. This beam monitoring device has been validated and is now installed at the Westdeutsches Protonentherapiezentrum Essen protontherapy center (WPE, Germany). The results obtained in both terms of spatial resolution and dose measurements are at least equal to the initials speci cations needed for PBS purposes. The detector measures the dose with a relative precision better than 1% in the range 0.5 Gy/min to 8 Gy/min while the spatial resolution is higher than 250 m. The technology has been patented and ve IC2/3 chambers were delivered to IBA. Nowadays, IBA produces the IC2/3 beam monitoring device as part of its Proteus 235 product

C. Courtois; G. Boissonnat; C. Brusasco; J. Colin; D. Cussol; J. M. Fontbonne; B. Marchand; T. Mertens; S. De Neuter; J. Perronnel

2013-06-28T23:59:59.000Z

453

Integration of a broad beam ion source with a high-temperature x-ray diffraction vacuum chamber  

Science Conference Proceedings (OSTI)

Here, the integration of a low energy, linearly variable ion beam current density, mechanically in situ adjustable broad beam ion source with a high-temperature x-ray diffraction (XRD) vacuum chamber is reported. This allows in situ XRD investigation of phase formation and evolution processes induced by low energy ion implantation. Special care has been taken to an independent adjustment of the ion beam for geometrical directing towards the substrate, a 15 mm small ion source exit aperture to avoid a secondary sputter process of the chamber walls, linearly variable ion current density by using a pulse length modulation (PLM) for the accelerating voltages without changing the ion beam density profile, nearly homogeneous ion beam distribution over the x-ray footprint, together with easily replaceable Kapton{sup Registered-Sign} windows for x-rays entry and exit. By combining a position sensitive x-ray detector with this PLM-modulated ion beam, a fast and efficient time resolved investigation of low energy implantation processes is obtained in a compact experimental setup.

Manova, D.; Bergmann, A.; Maendl, S.; Neumann, H.; Rauschenbach, B. [Leibniz-Institut fuer Oberflaechenmodifizierung e. V., Permoserstr. 15, 04318 Leipzig (Germany)

2012-11-15T23:59:59.000Z

454

Improved blue response and efficiency of A-Si:H solar cells deposited from disilane using a dual-chamber plasma system  

DOE Green Energy (OSTI)

Thin film amorphous silicon solar cells with glass/SnO/sub 2//p/i/n/Al structures and 6 to 7% AM1 conversion efficiencies were fabricated at rapid deposition rates in a newly constructed dual-chamber glow discharge deposition system. The 500 nm thick intrinsic layer was deposited at the rate of 1.7 nm/s using disilane (Si/sub 2/H/sub 6/)-helium mixtures. This deposition rate is an order of magnitude greater than conventional high efficiency amorphous silicon solar cell depositions. Residual boron doping effects at the p/i interface can severely degrade cell performance particularly when the intrinsic layer is deposited in one chamber of the dual-chamber system and the intrinsic layer is deposited in the other chamber that is free of boron contaminants. Parameters such as electrode spacing, Si/sub 2/H/sub 6/ partial pressure and flow rate were optimized to produce uniform deposition over large areas. At the substrate temperature T/sub s/ selected for solar cell intrinsic layer deposition, the spin density was measured to be a minimum at 5 x 10/sup 15//cm/sup 3/. For a given T/sub s/, an intrinsic layer deposited from Si/sub 2/H/sub 6/ absorbs fewer photons and can generate less current under solar simulation than a similar film produced from monosilane. Identical solar cells were deposited in either the single-chamber mode or the dual-chamber mode for comparison. Single-chamber mode cells perform poorly over the visible wavelengths and hence produce low short circuit currents. The dual-chamber mode cells show a significant improvement in blue response and a factor of two increase in short circuit current over the single-chamber mode cells. Under short circuit conditions, 15 mA/cm/sup 2/ was generated from rapidly deposited (1.7 nm/s) cells from disilane and 18 mA/cm/sup 2/ from low deposition rate (0.18 nm/s) monosilane cells. These values are comparable to or better than those reported for similar cells by other groups.

Rajeswaran, G.; Vanier, P.E.; Corderman, R.R.; Kampas, F.J.

1985-01-01T23:59:59.000Z

455

ENVIRONMENTAL CHAMBER STUDIES OF OZONE IMPACTS OF COATINGS VOCs Final Report to the California Air Resources Board Contract No. 07-339 By  

E-Print Network (OSTI)

An environmental chamber and modeling study was conducted to reduce uncertainties in atmospheric ozone impacts for volatile organic compounds (VOCs) emitted from coatings. Some coatings VOCs (Texanol and low-aromatic petroleum distillates) have near-zero or negative incremental ozone reactivities in chamber experiments, but calculations show positive ozone impacts in the atmosphere. Modeling indicated that experiments with increased light intensity and added H2O2 should give reactivities that better correlate with those in the atmosphere. After upgrading our chambers light source, experiments to test the new method performed as expected, and gave good correlations between experimental and atmospheric MIR values for the VOCs tested. These experiments also appear to be more sensitive to effects of VOCs on secondary organic aerosol (SOA) formation than previous experiments. Such experiments should be included in future environmental chamber reactivity studies, though other types of experiments are also needed for adequate mechanism evaluation. Experiments were also conducted to assess ozone impacts of ethyl methyl ketone oxime (EMKO), and soy ester solvents. The EMKO results indicated it has both radical sinks and NOx sources in its mechanism, and has no measurable impact on SOA formation. The EMKO mechanism that simulated the data gave a negative MIR of-1.27 gm O3 /gm VOC, but positive MOIR and EBIR values of

William P. L. Carter

2011-01-01T23:59:59.000Z

456

O{sub 2}({sup 1}{delta}) production in flowing He/O{sub 2} plasmas. I. Axial transport and pulsed power formats  

Science Conference Proceedings (OSTI)

Chemical oxygen-iodine lasers (COILs) have promising applications due to their high efficiency and ease of scaling to multikilowatt powers. Recent research has focused on pumping the iodine with O{sub 2}({sup 1}{delta}) produced by electric discharges. In a previous work, a global model was used to develop reaction mechanisms and determine the specific energy deposition (eV/O{sub 2}) required to obtain high O{sub 2}({sup 1}{delta}) yields for electric discharge COILs. Experiments have recently achieved positive laser gain and oscillation with these energy depositions and have highlighted the importance of axial expansion of the plasma in optimizing excitation of the O{sub 2}({sup 1}{delta}). In this work, the consequences of axial transport on O{sub 2}({sup 1}{delta}) yields have been computationally investigated in flowing He/O{sub 2} plasmas at a few Torrs using a one-dimensional plasma hydrodynamics and kinetics model. We show that the experimentally observed extension of the plasma glow upstream and downstream of the electrodes is due to electron diffusion and capacitive coupling of the radio-frequency power source. We also show that {approx_equal}50% higher O{sub 2}({sup 1}{delta}) yields can be achieved with a pulsed discharge combined with continuous-wave discharge.

Stafford, D. Shane; Kushner, Mark J. [Department of Theoretical and Applied Mechanics, University of Illinois, Urbana, Illinois 61801 (United States); Department of Electrical and Computer Engineering, Iowa State University, Ames, Iowa 50011 (United States)

2005-10-01T23:59:59.000Z

457

Expanding the One-Dimensional CdS-CdSe Composition Landscape: Axially Anisotropic CdS{sub 1-x}Se{sub x} Nanorods  

Science Conference Proceedings (OSTI)

We report the synthesis and characterization of CdS{sub 1x}Se{sub x} nanorods with axial anisotropy. These nanorods were synthesized via single injection of a mixture of trioctylphosphine sulfur and selenium precursors to a cadmiumphosphonate complex at high temperature. Transmission electron microscopy shows nanoparticle morphology changes with relative sulfur and selenium loading. When the synthetic selenium loading is between 5% and 10% of total chalcogenides, the nanorods exhibit pronounced axial anisotropy characterized by a thick head and a thin tail. The nanorods band gap red shifts with increasing selenium loading. X-ray diffraction reveals that CdS{sub 1x}Se{sub x} nanorods have a wurtzite crystal structure with a certain degree of alloying. High-resolution and energy-filtered transmission electron microscopy and energy-dispersive X-ray spectroscopy confirm the head of the anisotropic nanorods is rich in selenium, whereas the tail is rich in sulfur. Time evolution and mechanistic studies confirm the nanorods form by quick growth of the CdSe-rich head, followed by slow growth of the CdS-rich tail. Metal photodeposition reactions with 575 nm irradiation, which is mostly absorbed by the CdSe-rich segment, show effective electronic communication between the nanorod head and tail segments.

Ruberu, T. Purnima A.; Vela, Javier

2011-06-02T23:59:59.000Z

458

S T A T E OF CONNECTICUT E X E C U T I V E CHAMBERS M  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

T T A T E OF CONNECTICUT E X E C U T I V E CHAMBERS M . JODI R E L L GOVERNOR The Honorable Steven Chu, Secretary United States Department of Energy 1000 Independence Avenue, S. W. Washington, D.C. 20585 March 23,2009 Dear Secretary Chu: Re: State Energy Program Assurances In accordance with Section 41 0 of the American Recovery and Reinvestment Act of 2009,I hereby notify you that I have obtained necessary assurances that each of the following will occur: (1) The applicable State regulatory authority will seek to implement, in appropriate proceedings for each electric and gas utility, with respect to which the State regulatory authority has ratemaking authority, a general policy that ensures that utility financial incentives are aligned with helping their customers use energy more efficiently and that provide timely cost recovery

459

Hybrid bubble chamber studies of K+ p and K- p interactions at 75-GeV/c  

DOE Green Energy (OSTI)

We propose to expose the FNAL 30' liquid hydrogen bubble chamber to K{sup +} and K{sup -} beams both at 75 GeV/c. Each exposure consists of 100,000 equivalent K pictures. We plan to use the upstream tagging system currently in place and a downstream spectrometer with acceptance considerably increased over that of