Sample records for high pressure hose

  1. 30 CFR 56.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  2. 30 CFR 57.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  3. 30 CFR 57.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  4. 30 CFR 56.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  5. 30 CFR 56.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  6. 30 CFR 57.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  7. 30 CFR 57.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  8. 30 CFR 56.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  9. 30 CFR 56.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  10. 30 CFR 57.13021 - High-pressure hose connections.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13021 High-pressure hose connections. Except where automatic shutoff valves are...

  11. 6. DETAIL OF HIGHPRESSURE COMPRESSED AIR HOSE IN SOUTHWEST CORNER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. DETAIL OF HIGH-PRESSURE COMPRESSED AIR HOSE IN SOUTHWEST CORNER OF SHIPPING AND RECEIVING ROOM (109) - Vandenberg Air Force Base, Space Launch Complex 3, Vehicle Support Building, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  12. Observation of a Long-Wavelength Hosing Modulation of a High-Intensity Laser Pulse in Underdense Plasma

    SciTech Connect

    Kaluza, M. C. [Blackett Laboratory, Imperial College London, London SW7 2BZ (United Kingdom); Institut fuer Optik und Quantenelektronik, Friedrich-Schiller-Universitaet, Max-Wien-Platz 1, 07743 Jena (Germany); Helmholtz-Institut Jena, Helmholtzweg 4, 07743 Jena (Germany); Mangles, S. P. D.; Najmudin, Z.; Dangor, A. E. [Blackett Laboratory, Imperial College London, London SW7 2BZ (United Kingdom); Thomas, A. G. R.; Krushelnick, K. [Blackett Laboratory, Imperial College London, London SW7 2BZ (United Kingdom); Center for Ultrafast Optical Science (CUOS), University of Michigan, Ann Arbor, Michigan 48109 (United States); Murphy, C. D. [Blackett Laboratory, Imperial College London, London SW7 2BZ (United Kingdom); Central Laser Facility, Rutherford Appleton Laboratory, Oxon OX11 0QX (United Kingdom); Clarendon Laboratory, University of Oxford, Oxford OX1 3PU (United Kingdom); Collier, J. L.; Divall, E. J.; Foster, P. S.; Hooker, C. J.; Langley, A. J.; Smith, J. [Central Laser Facility, Rutherford Appleton Laboratory, Oxon OX11 0QX (United Kingdom)

    2010-08-27

    We report the first experimental observation of a long-wavelength hosing modulation of a high-intensity laser pulse. Side-view images of the scattered optical radiation at the fundamental wavelength of the laser reveal a transverse oscillation of the laser pulse during its propagation through underdense plasma. The wavelength of the oscillation {lambda}{sub hosing} depends on the background plasma density n{sub e} and scales as {lambda}{sub hosing{approx}}n{sub e}{sup -3/2}. Comparisons with an analytical model and two-dimensional particle-in-cell simulations reveal that this laser hosing can be induced by a spatiotemporal asymmetry of the intensity distribution in the laser focus which can be caused by a misalignment of the parabolic focusing mirror or of the diffraction gratings in the pulse compressor.

  13. 49 CFR 178.345-9 - Pumps, piping, hoses and connections.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Pumps, piping, hoses and connections. 178...Vehicle Transportation § 178.345-9 Pumps, piping, hoses and connections. ...pressure within a cargo tank does not exceed test pressure. (b) Each hose,...

  14. High Blood Pressure

    MedlinePLUS

    ... of this page please turn Javascript on. High Blood Pressure What Is High Blood Pressure? Click for more information Blood pressure is ... active. So it varies throughout the day. High Blood Pressure (Hypertension) A systolic blood pressure of 140 ...

  15. Self-sealing, easily purged quick-disconnect hose coupling

    NASA Technical Reports Server (NTRS)

    Leyerle, R. B.

    1970-01-01

    Coupling for pressurized hoses handles gas or liquid, is easily purged, and automatically seals the hose when disconnected. Volatile or toxic materials can be isolated before the connection is broken. This device may interest food processors and manufacturers of fluid delivery systems.

  16. High Blood Pressure (Hypertension)

    MedlinePLUS

    ... Page Text Size: A A A Listen High Blood Pressure (Hypertension) Nearly 1 in 3 American adults ... if your doctor prescribes it, medicine. What Is Blood Pressure? Blood pressure is the force of blood ...

  17. High Blood Pressure

    MedlinePLUS

    ... during light physical activity or exercise. What Is Blood Pressure? Blood pressure is the force of blood ... stated as 120/80. Do You Have High Blood Pressure? One reason to have regular visits to ...

  18. Plastic tubing protects flexible copper hose

    NASA Technical Reports Server (NTRS)

    Mellgren, B. E.

    1966-01-01

    Flexible copper purge and coolant hoses is covered with a high-temperature shrinkable plastic for protection against severe vibration during rocket engine tests. This type of tubing is being used on all flexible water tubes used in F-1 engine tests.

  19. Solar-collector silicone hose life test

    SciTech Connect

    Donohue, H.F.; Morse, R.L.

    1982-08-11

    A life-cycle test of the recommended silicone hose installation was performed to verify that this configuration would protect the integrity of the system. The test rig was filled with inhibited water which was circulated through the test article. The water was alternately heated and pressurized and then cooled to simulate day and night operation in Arizona. The test indicated that the recommended modification would provide an economical and long-range solution to the problem.

  20. High Blood Pressure in Pregnancy

    MedlinePLUS

    ... Are the Effects of High Blood Pressure in Pregnancy? Although many pregnant women with high blood pressure ... Common Are High Blood Pressure and Preeclampsia in Pregnancy? High blood pressure problems occur in 6 percent ...

  1. High temperature pressure gauge

    DOEpatents

    Echtler, J. Paul (Pittsburgh, PA); Scandrol, Roy O. (Library, PA)

    1981-01-01

    A high temperature pressure gauge comprising a pressure gauge positioned in fluid communication with one end of a conduit which has a diaphragm mounted in its other end. The conduit is filled with a low melting metal alloy above the diaphragm for a portion of its length with a high temperature fluid being positioned in the remaining length of the conduit and in the pressure gauge.

  2. High-pressure microfluidics

    NASA Astrophysics Data System (ADS)

    Hjort, K.

    2015-03-01

    When using appropriate materials and microfabrication techniques, with the small dimensions the mechanical stability of microstructured devices allows for processes at high pressures without loss in safety. The largest area of applications has been demonstrated in green chemistry and bioprocesses, where extraction, synthesis and analyses often excel at high densities and high temperatures. This is accessible through high pressures. Capillary chemistry has been used since long but, just like in low-pressure applications, there are several potential advantages in using microfluidic platforms, e.g., planar isothermal set-ups, large local variations in geometries, dense form factors, small dead volumes and precisely positioned microstructures for control of reactions, catalysis, mixing and separation. Other potential applications are in, e.g., microhydraulics, exploration, gas driven vehicles, and high-pressure science. From a review of the state-of-art and frontiers of high pressure microfluidics, the focus will be on different solutions demonstrated for microfluidic handling at high pressures and challenges that remain.

  3. 29 CFR 1910.158 - Standpipe and hose systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...needed. (ii) Standpipe systems installed after January 1...may remain in use on existing systems. However, after the effective...below 30 psi (210 kPa). The dynamic pressure at the nozzle shall...supply for standpipe and hose systems, which are provided for...

  4. High Blood Pressure

    NSDL National Science Digital Library

    American Association for the Advancement of Science (; )

    2004-01-01

    The Science Inside: High Blood PressureThis booklet explains what health professionals know about high blood pressure or hypertension, one of the leading causes of heart disease and stroke. It shows how to prevent high blood pressure, as well as how to care for yourself if you have been diagnosed with the disease. The Science Inside e-book series is intended to be a bridge between the consumer health brochure and the scientific paper, the booklets in this series focus on the science that is inside of, or behind, the disease its cause, its possible cure, its treatment, promising research, and so on. These booklets are designed to appeal to people who have not had the opportunity to study the science and to understand why they may have been given some of the advice that they have been given through some of the more consumer-oriented materials.

  5. High blood pressure - infants

    MedlinePLUS

    ... click may be heard if a bicuspid aortic valve occurs with the coarctation. Other tests in infants with high blood pressure will try to find the cause of the problem. Such tests may include: A special type of x-ray that uses a dye to look at ...

  6. High pressure furnace

    DOEpatents

    Morris, D.E.

    1993-09-14

    A high temperature high pressure furnace has a hybrid partially externally heated construction. A metallic vessel fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum)). The disclosed alloy is fabricated into 11/4 or 2 inch, 32 mm or 50 mm bar stock and has a length of about 22 inches, 56 cm. This bar stock has an aperture formed therein to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the vessel is provided with a small blind aperture into which a thermocouple can be inserted. The closed end of the vessel is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior. 19 figures.

  7. High pressure oxygen furnace

    DOEpatents

    Morris, Donald E. (Kensington, CA)

    1992-01-01

    A high temperature high pressure oxygen furnace having a hybrid partially externally heated construction is disclosed. A metallic bar fabricated from an alloy having a composition of at least 45% nickel, 15% chrome, and 10% tungsten is utilized (the preferred alloy including 55% nickel, 22% chrome, 14% tungsten, 2% molybdenum, 3% iron (maximum) and 5% cobalt (maximum). The disclosed alloy is fabricated into 11/4 inch bar stock and has a length of about 17 inches. This bar stock is gun drilled for over 16 inches of its length with 0.400 inch aperture to define a closed high temperature, high pressure oxygen chamber. The opposite and closed end of the bar is provided with a small support aperture into which both a support and a thermocouple can be inserted. The closed end of the gun drilled bar is inserted into an oven, preferably heated by standard nickel chrome electrical elements and having a heavily insulated exterior.

  8. Questions and Answers about High Blood Pressure

    MedlinePLUS

    ... High Blood Pressure Questions and Answers About High Blood Pressure What is high blood pressure? Blood pressure is the force of blood ... a doctor. Am I at risk for high blood pressure? Anyone can develop high blood pressure. But ...

  9. High pressure ratio turbocharger

    SciTech Connect

    Woollenweber, W.E.

    1991-06-25

    This patent describes a turbocharger system for an internal combustion engine. It comprises means forming a turbine adapted to be driven by exhaust gas from an internal combustion engine comprising: a turbine wheel having a central core and outwardly extending vanes, the turbine wheel being rotatable about a central axis; a meridionally divided volute for exhaust gas surrounding the turbine wheel, the meridionally divided volute including a divider wall defining first and second volute passageways with openings at the turbine wheel; means forming a high-pressure compressor driven by the turbine means, the high-pressure compressor comprising: rotating compressor blades, the compressor blades adapted to be driven in rotation about the central axis by the turbine means to deliver a flow of air at high pressures for an internal combustion engine, and blades being moveable about longitudinal axes generally transverse to the central axis to impart positive or negative pre-whirl motion to the air leaving the stator blades prior to entering the rotating blades of the compressor stage; closure means for providing a flow of engine exhaust gas from one of the first and second volute passageways into the turbine wheel; and a control means for operating the closure means and the stator blades in synchronization.

  10. High Blood Pressure and Women

    MedlinePLUS

    ... in life. Blood pressure during childbearing years Do birth control pills cause high blood pressure? Medical researchers have found that birth control pills increase blood pressure in some women. It's ...

  11. Pressure Dome for High-Pressure Electrolyzer

    NASA Technical Reports Server (NTRS)

    Norman, Timothy; Schmitt, Edwin

    2012-01-01

    A high-strength, low-weight pressure vessel dome was designed specifically to house a high-pressure [2,000 psi (approx. = 13.8 MPa)] electrolyzer. In operation, the dome is filled with an inert gas pressurized to roughly 100 psi (approx. = 690 kPa) above the high, balanced pressure product oxygen and hydrogen gas streams. The inert gas acts to reduce the clamping load on electrolyzer stack tie bolts since the dome pressure acting axially inward helps offset the outward axial forces from the stack gas pressure. Likewise, radial and circumferential stresses on electrolyzer frames are minimized. Because the dome is operated at a higher pressure than the electrolyzer product gas, any external electrolyzer leak prevents oxygen or hydrogen from leaking into the dome. Instead the affected stack gas stream pressure rises detectably, thereby enabling a system shutdown. All electrical and fluid connections to the stack are made inside the pressure dome and require special plumbing and electrical dome interfaces for this to be accomplished. Further benefits of the dome are that it can act as a containment shield in the unlikely event of a catastrophic failure. Studies indicate that, for a given active area (and hence, cell ID), frame outside diameter must become ever larger to support stresses at higher operating pressures. This can lead to a large footprint and increased costs associated with thicker and/or larger diameter end-plates, tie-rods, and the frames themselves. One solution is to employ rings that fit snugly around the frame. This complicates stack assembly and is sometimes difficult to achieve in practice, as its success is strongly dependent on frame and ring tolerances, gas pressure, and operating temperature. A pressure dome permits an otherwise low-pressure stack to operate at higher pressures without growing the electrolyzer hardware. The pressure dome consists of two machined segments. An O-ring is placed in an O-ring groove in the flange of the bottom segment and is trapped by the flange on the top dome segment when these components are bolted together with high-strength bolts. The pressure dome has several unique features. It is made (to ASME Pressure Vessel guidelines) in a high-strength aluminum alloy with the strength of stainless steel and the weight benefits of aluminum. The flange of the upper dome portion contains specially machined flats for mounting the dome, and other flats dedicated to the special feedthroughs for electrical connections. A pressure dome can be increased in length to house larger stacks (more cells) of the same diameter with the simple addition of a cylindrical segment. To aid in dome assembly, two stainless steel rings are employed. One is used beneath the heads of the high-strength bolts in lieu of individual hardened washers, and another is used instead of individual nuts. Like electrolyzers could be operated at low or high pressures simply by operating the electrolyzer outside or inside a pressurized dome.

  12. Automated Facility For Cleaning Large Flex Hoses

    NASA Technical Reports Server (NTRS)

    Landry, Louis E.

    1995-01-01

    Technicians no longer exposed to hazardous cleaning materials. Proposed computer-controlled facility cleans bellow-type expansion joints and large flex hoses. Major portions of automated cleaning facility contained in clean room. One piece of equipment in clean room tower in which hose or expansion joint to be cleaned hoisted by hydraulic machinery and hung vertically. Once hose or expansion joint hung in required position, technician initiates programmed cleaning procedure from console on computer monitoring system. Procedure includes degreasing, cleaning with detergents, rinsing, pickling, and passivating operations. After cleaning completed, technician removes hose or expansion joint from tower and wraps open ends to prevent recontamination of interior.

  13. Chromium at High Pressure

    NASA Astrophysics Data System (ADS)

    Jaramillo, Rafael

    2012-02-01

    Chromium has long served as the archetype of spin density wave magnetism. Recently, Jaramillo and collaborators have shown that Cr also serves as an archetype of magnetic quantum criticality. Using a combination of x-ray diffraction and electrical transport measurements at high pressures and cryogenic temperatures in a diamond anvil cell, they have demonstrated that the N'eel transition (TN) can be continuously suppressed to zero, with no sign of a concurrent structural transition. The order parameter undergoes a broad regime of exponential suppression, consistent with the weak coupling paradigm, before deviating from a BCS-like ground state within a narrow but accessible quantum critical regime. The quantum criticality is characterized by mean field scaling of TN and non mean field scaling of the transport coefficients, which points to a fluctuation-induced reconstruction of the critical Fermi surface. A comparison between pressure and chemical doping as means to suppress TN sheds light on different routes to the quantum critical point and the relevance of Fermi surface nesting and disorder at this quantum phase transition. The work by Jaramillo et al. is broadly relevant to the study of magnetic quantum criticality in a physically pure and theoretically tractable system that balances elements of weak and strong coupling. [4pt] [1] R. Jaramillo, Y. Feng, J. Wang & T. F. Rosenbaum. Signatures of quantum criticality in pure Cr at high pressure. Proc. Natl. Acad. Sci. USA 107, 13631 (2010). [0pt] [2] R. Jaramillo, Y. Feng, J. C. Lang, Z. Islam, G. Srajer, P. B. Littlewood, D. B. McWhan & T. F. Rosenbaum. Breakdown of the Bardeen-Cooper-Schrieffer ground state at a quantum phase transition. Nature 459, 405 (2009).

  14. High Blood Pressure Fact Sheet

    MedlinePLUS

    ... this? Submit What's this? Submit Button Related CDC Web Sites Heart Disease Stroke High Blood Pressure Salt ... Prevent and Control Chronic Diseases Million Hearts® WISEWOMAN Web Sites with More Information About High Blood Pressure ...

  15. 46 CFR 105.35-15 - Fire hose.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...garden hose nozzle of good grade bronze or equivalent metal. (e) All fittings on fire hose shall be of brass, copper, or other suitable corrosion resistant metal. (f) A length of fire hose shall be...

  16. 46 CFR 105.35-15 - Fire hose.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...garden hose nozzle of good grade bronze or equivalent metal. (e) All fittings on fire hose shall be of brass, copper, or other suitable corrosion resistant metal. (f) A length of fire hose shall be...

  17. High pressure capillary connector

    DOEpatents

    Renzi, Ronald F.

    2005-08-09

    A high pressure connector capable of operating at pressures of 40,000 psi or higher is provided. This connector can be employed to position a first fluid-bearing conduit that has a proximal end and a distal end to a second fluid-bearing conduit thereby providing fluid communication between the first and second fluid-bearing conduits. The connector includes (a) an internal fitting assembly having a body cavity with (i) a lower segment that defines a lower segment aperture and (ii) an interiorly threaded upper segment, (b) a first member having a first member aperture that traverses its length wherein the first member aperture is configured to accommodate the first fluid-bearing conduit and wherein the first member is positioned in the lower segment of the internal fitting assembly, and (c) a second member having a second member aperture that traverses its length wherein the second member is positioned in the upper segment of the fitting assembly and wherein a lower surface of the second member is in contact with an upper surface of the first member to assert a compressive force onto the first member and wherein the first member aperture and the second member aperture are coaxial.

  18. High pressure mechanical seal

    NASA Technical Reports Server (NTRS)

    Babel, Henry W. (Inventor); Anderson, Raymond H. (Inventor)

    1996-01-01

    A relatively impervious mechanical seal is formed between the outer surface of a tube and the inside surface of a mechanical fitting of a high pressure fluid or hydraulic system by applying a very thin soft metal layer onto the outer surface of the hard metal tube and/or inner surface of the hard metal fitting. The thickness of such thin metal layer is independent of the size of the tube and/or fittings. Many metals and alloys of those metals exhibit the requisite softness, including silver, gold, tin, platinum, indium, rhodium and cadmium. Suitably, the coating is about 0.0025 millimeters (0.10 mils) in thickness. After compression, the tube and fitting combination exhibits very low leak rates on the order or 10.sup.-8 cubic centimeters per second or less as measured using the Helium leak test.

  19. Safety Modification of Cam-and-Groove Hose Coupling

    NASA Technical Reports Server (NTRS)

    Schwindt, Paul; Littlefield, Alan

    2008-01-01

    A modification has been made in the mating halves of a cam-and-groove hose coupling to prevent rapid separation of the halves in the event that the cam levers are released while the fluid in the hose is pressurized. The need for this modification arises because commercial off-the-shelf cam-and-groove hose-coupling halves do not incorporate safety features to prevent separation in the pressurized state. Especially when the pressurized fluid is compressible (e.g., steam or compressed air), the separated halves can be propelled with considerable energy, causing personal injury and/or property damage. Therefore, one purpose served by the modification is to provide for venting to release compressive energy in a contained and safe manner while preventing personal injury and/or property damage. Another purpose served by the modification, during the process of connecting the coupling halves, is to ensure that the coupling halves are properly aligned before the cam levers can be locked into position.

  20. High pressure, high temperature transducer

    NASA Technical Reports Server (NTRS)

    Vrolyk, John J. (Inventor)

    1977-01-01

    The pressure measurement system utilizes two bourdon tubes with an active side connected to a test specimen and a reference side connected to an outside source. The tubes are attached to a single extensometer measuring relative displacement. The active side deflects when gases vent a specimen failure. The reference side is independently pressurized to a test pressure and provides a zero reference while providing a pressure calibration reference for the active side. The deflection noted by the active side at specimen failure is duplicated on the reference side by venting until an appropriate magnitude of pressure versus deflection is determined. In this way the pressure which existed inside the specimen prior to failure can be determined.

  1. High-pressure neutron diffraction

    SciTech Connect

    Xu, Hongwu [Los Alamos National Laboratory

    2011-01-10

    This lecture will cover progress and prospect of applications of high-pressure neutron diffraction techniques to Earth and materials sciences. I will first introduce general high-pressure research topics and available in-situ high-pressure techniques. Then I'll talk about high-pressure neutron diffraction techniques using two types of pressure cells: fluid-driven and anvil-type cells. Lastly, I will give several case studies using these techniques, particularly, those on hydrogen-bearing materials and magnetic transitions.

  2. High Blood Pressure in Pregnancy

    MedlinePLUS

    ... of the baby. Controlling your blood pressure during pregnancy and getting regular prenatal care are important for ... your baby. Treatments for high blood pressure in pregnancy may include close monitoring of the baby, lifestyle ...

  3. High Blood Pressure

    MedlinePLUS

    ... pressure - a hypertension Google+ hangout in honor of World Hypertension Day 04/18/2013 Moderated by American ... live on April 5, 2013 in honor of World Health Day on Sunday, April 7. The NHLBI " ...

  4. Electrokinetically pumped high pressure sprays

    DOEpatents

    Schoeniger, Joseph S. (Oakland, CA); Paul, Phillip H. (Livermore, CA); Schoeniger, Luke (Pittsford, NY)

    2005-11-01

    An electrokinetic pump capable of producing high pressure is combined with a nozzle having a submicron orifice to provide a high pressure spray device. Because of its small size, the device can be contained within medical devices such as an endoscope for delivering biological materials such as DNA, chemo therapeutic agents, or vaccines to tissues and cells.

  5. Electrokinetically pumped high pressure sprays

    DOEpatents

    Schoeniger, Joseph S. (Oakland, CA); Paul, Phillip H. (Livermore, CA); Schoeniger, Luke (Pittsford, NY)

    2002-01-01

    An electrokinetic pump capable of producing high pressure is combined with a nozzle having a submicron orifice to provide a high pressure spray device. Because of its small size, the device can be contained within medical devices such as an endoscope for delivering biological materials such as DNA, chemo therapeutic agents, or vaccines to tissues and cells.

  6. Reusable High-Pressure Connector

    NASA Technical Reports Server (NTRS)

    Jensen, H. O. C.; Maltby, H. M.; Stein, J. A.

    1983-01-01

    Fluid line connector for high pressure tests has split ferrule, nut, and O-ring seal. Following test, ferrule nut, and O-ring fitting are removed leaving line unaltered except for bushing braze to free end. Connector assures strong joint for high-pressure testing without redundant parts requiring postest debrazing.

  7. Fundamentals of high pressure adsorption.

    PubMed

    Zhou, Yaping; Zhou, Li

    2009-12-01

    High-pressure adsorption attracts research interests following the world's attention to alternative fuels, and it exerts essential effect on the study of hydrogen/methane storage and the development of novel materials addressing to the storage. However, theoretical puzzles in high-pressure adsorption hindered the progress of application studies. Therefore, the present paper addresses the major theoretical problems that challenged researchers: i.e., how to model the isotherms with maximum observed in high-pressure adsorption; what is the adsorption mechanism at high pressures; how do we determine the quantity of absolute adsorption based on experimental data. Ideology and methods to tackle these problems are elucidated, which lead to new insights into the nature of high-pressure adsorption and progress in application studies, for example, in modeling multicomponent adsorption, hydrogen storage, natural gas storage, and coalbed methane enrichment, was achieved. PMID:19928941

  8. Fundamentals of high pressure adsorption

    SciTech Connect

    Zhou, Y.P.; Zhou, L. [Tianjin University, Tianjin (China). High Pressure Adsorption Laboratory

    2009-12-15

    High-pressure adsorption attracts research interests following the world's attention to alternative fuels, and it exerts essential effect on the study of hydrogen/methane storage and the development of novel materials addressing to the storage. However, theoretical puzzles in high-pressure adsorption hindered the progress of application studies. Therefore, the present paper addresses the major theoretical problems that challenged researchers: i.e., how to model the isotherms with maximum observed in high-pressure adsorption; what is the adsorption mechanism at high pressures; how do we determine the quantity of absolute adsorption based on experimental data. Ideology and methods to tackle these problems are elucidated, which lead to new insights into the nature of high-pressure adsorption and progress in application studies, for example, in modeling multicomponent adsorption, hydrogen storage, natural gas storage, and coalbed methane enrichment, was achieved.

  9. Beam hosing instability in overdense plasma

    SciTech Connect

    Schroeder, C. B.; Benedetti, C.; Esarey, E.; Gruener, F. J.; Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2012-12-21

    Transverse stability of the drive beam is critical to plasma wakefield accelerators. A long, relativistic particle beam propagating in an overdense plasma is subject to beam envelope modulation and hosing (centroid displacement) instabilities. Coupled equations for the beam centroid and envelope are derived. The growth rate for beam hosing is examined including return current effects (where the beam radius is of order the plasma skin depth) in the long-beam, strongly-coupled, overdense regime.

  10. High-Pressure Vibrational Spectroscopy.

    NASA Astrophysics Data System (ADS)

    Pogson, Mark

    1987-09-01

    Available from UMI in association with The British Library. Requires signed TDF. The study of solids at high pressure and variable temperature enables development of accurate interatomic potential functions over wide ranges of interatomic distances. A review of the main models used in the determination of these potentials is given in Chapter one. A discussion of phonon frequency as a variable physical parameter reflecting the interatomic potential is given. A high pressure Raman study of inorganic salts of the types MSCN, (M = K,Rb,Cs & NH_4^+ ) and MNO_2, (M = K,Na) has been completed. The studies have revealed two new phases in KNO_2 and one new phase in NaNO _2 at high pressure. The accurate phonon shift data have enabled the determination of the pure and biphasic stability regions of the phases of KNO _2. A discussion of the B1, B2 relationship of univalent nitrites is also given. In the series of thiocyanates studied new phases have been found in all four materials. In both the potassium and rubidium salts two new phases have been detected, and in the ceasium salt one new phase has been detected, all at high pressure, from accurate phonon shift data. These transitions are discussed in terms of second-order mechanisms with space groups suggested for all phases, based on Landau's theory of second-order phase transitions. In the ammonium salt one new phase has been detected. This new phase transition has been interpreted as a second-order transition. The series of molecular crystals CH_3 HgX, (X = Cl,Br & I) has been studied at high pressure and at variable temperature. In Chapter five, their phase behaviour at high pressure is detailed along with the pressure dependencies of their phonon frequencies. In the chloride and the bromide two new phases have been detected. In the bromide one has been detected at high temperature and one at high pressure, and latter being interpreted as the stopping of the methyl rotation. In the chloride one phase has been found at both low temperature as well as high pressure, and the other only at high pressure, the latter again associated with the stopping of methyl rotation. The iodide displays two high pressure transitions. A Raman -active soft-mode has been observed in all three analogues, at both high pressure and variable temperature. For the chloride and bromide analogues there is a discussion of the nature of the soft-mode along with the mechanism associated with the I/II transition. The results of the X-ray crystal structure determination of CH_3HgBr at ambient temperature and pressure are given.

  11. High-Pressure Transducer Package

    NASA Technical Reports Server (NTRS)

    Wamstad, D.; Glenn, M.

    1987-01-01

    Enclosure for silicon device ensures accurate measurements of cryogenic liquids. Package holds silicon sensor in uniform compression around periphery and helps ensure accurate, stable, and repeatable pressure measurements. Mounting assembly housed in package of stainless steel. Materials selected for equality of thermal expansion and for pressure-sealing properties. Besides its high-pressure, low-temperature characteristics, package withstands vibrations as severe as 400 times standard gravitational acceleration at 0 to 2,000 Hz.

  12. Hypertension (High Blood Pressure)

    NSDL National Science Digital Library

    Patient Education Institute

    This patient education program discusses hypertension including the causes, complications, risk factors, diagnosis, and management of the disease. It also explains what blood pressure is. This resource is a MedlinePlus Interactive Health Tutorial from the National Library of Medicine, designed and developed by the Patient Education Institute. NOTE: This tutorial requires a special Flash plug-in, version 4 or above. If you do not have Flash, you will be prompted to obtain a free download of the software before you start the tutorial. You will also need an Acrobat Reader, available as a free download, in order to view the Reference Summary.

  13. High pressure ices

    PubMed Central

    Hermann, Andreas; Ashcroft, N. W.; Hoffmann, Roald

    2012-01-01

    H2O will be more resistant to metallization than previously thought. From computational evolutionary structure searches, we find a sequence of new stable and meta-stable structures for the ground state of ice in the 1–5 TPa (10 to 50 Mbar) regime, in the static approximation. The previously proposed Pbcm structure is superseded by a Pmc21 phase at p = 930 GPa, followed by a predicted transition to a P21 crystal structure at p = 1.3 TPa. This phase, featuring higher coordination at O and H, is stable over a wide pressure range, reaching 4.8 TPa. We analyze carefully the geometrical changes in the calculated structures, especially the buckling at the H in O-H-O motifs. All structures are insulating—chemistry burns a deep and (with pressure increase) lasting hole in the density of states near the highest occupied electronic levels of what might be component metallic lattices. Metallization of ice in our calculations occurs only near 4.8 TPa, where the metallic C2/m phase becomes most stable. In this regime, zero-point energies much larger than typical enthalpy differences suggest possible melting of the H sublattice, or even the entire crystal. PMID:22207625

  14. Myths about High Blood Pressure

    MedlinePLUS

    ... can increase blood pressure dramatically. It can also cause heart failure, lead to stroke and produce irregular heartbeats. Too much alcohol can contribute to high triglycerides, cancer, obesity, alcoholism, suicide and accidents, and it can be ...

  15. Electrokinetic high pressure hydraulic system

    DOEpatents

    Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA)

    2000-01-01

    A compact high pressure hydraulic pump having no moving mechanical parts for converting electric potential to hydraulic force. The electrokinetic pump, which can generate hydraulic pressures greater than 2500 psi, can be employed to compress a fluid, either liquid or gas, and manipulate fluid flow. The pump is particularly useful for capillary-base systems. By combining the electrokinetic pump with a housing having chambers separated by a flexible member, fluid flow, including high pressure fluids, is controlled by the application of an electric potential, that can vary with time.

  16. Electrokinetic high pressure hydraulic system

    DOEpatents

    Paul, Phillip H.; Rakestraw, David J.; Arnold, Don W.; Hencken, Kenneth R.; Schoeniger, Joseph S.; Neyer, David W.

    2003-06-03

    An electrokinetic high pressure hydraulic pump for manipulating fluids in capillary-based system. The pump uses electro-osmotic flow to provide a high pressure hydraulic system, having no moving mechanical parts, for pumping and/or compressing fluids, for providing valve means and means for opening and closing valves, for controlling fluid flow rate, and manipulating fluid flow generally and in capillary-based systems (microsystems), in particular. The compact nature of the inventive high pressure hydraulic pump provides the ability to construct a micro-scale or capillary-based HPLC system that fulfills the desire for small sample quantity, low solvent consumption, improved efficiency, the ability to run samples in parallel, and field portability. Control of pressure and solvent flow rate is achieved by controlling the voltage applied to an electrokinetic pump.

  17. Electrokinetic high pressure hydraulic system

    DOEpatents

    Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA); Arnold, Don W. (Livermore, CA); Hencken, Kenneth R. (Pleasanton, CA); Schoeniger, Joseph S. (Oakland, CA); Neyer, David W. (Castro Valley, CA)

    2001-01-01

    An electrokinetic high pressure hydraulic pump for manipulating fluids in capillary-based systems. The pump uses electro-osmotic flow to provide a high pressure hydraulic system, having no moving mechanical parts, for pumping and/or compressing fluids, for providing valve means and means for opening and closing valves, for controlling fluid flow rate, and manipulating fluid flow generally and in capillary-based systems (Microsystems), in particular. The compact nature of the inventive high pressure hydraulic pump provides the ability to construct a micro-scale or capillary-based HPLC system that fulfills the desire for small sample quantity, low solvent consumption, improved efficiency, the ability to run samples in parallel, and field portability. Control of pressure and solvent flow rate is achieved by controlling the voltage applied to an electrokinetic pump.

  18. Pressurized high frequency thermoacoustic engines

    NASA Astrophysics Data System (ADS)

    Webb, Nicholas D.

    Acoustic heat engines show much promise for converting waste heat to electricity. Since most applications require high power levels, high frequency thermoacoustic engines can reach such performance by operating with a pressurized working gas. Results on a 3 kHz prime mover, consisting of a quarter-wave resonator and a random stack material between two heat exchangers, show that the acoustic power from such a device is raised substantially as the working gas is pressurized. At pressures up to approximately 10 bar, the increase in acoustic power is approximately linear to the increase in pressure, and thus is an effective way to increase the power output of thermoacoustic engines. Since the heat input was not changed during the experiments, the increases in acoustic power translate directly to increases in engine efficiency which is calculated as the output acoustic power divided by the input heat power. In most experiments run in this study, the engine efficiency increased by a factor of at least 4 as the pressure was increased from 2 bar up to about 10 bar. Further increases in pressure lead to acoustic power saturation and eventual attenuation. This is most likely due to a combination of several factors including the shrinking thermal penetration depth, and the fact that the losses increase faster with pressure in a random stack material than in traditional parallel plates. Pressurization also leads to a lower DeltaT for onset of oscillations in the range of 10 bar of mean pressure, potentially opening up even more heat sources that can power a thermoacoustic engine. Results from another 3 kHz engine, one that was pressurized itself as opposed to being placed in a pressurized chamber, are also presented. The configuration of this engine solves the problem of how to simultaneously pressurize the engine and inject heat into the hot heat exchanger. It was also noted that the geometry of the resonator cavity in the quarter wavelength pressurized engine plays an important role in the determination of the resonance frequency of the engine, and special care needs to be taken to ensure that the stack is positioned correctly with regards to the resonance frequency. Pressurization promises to greatly increase the number of applications of acoustic engines to a variety of real world settings, providing a key source of renewable energy for the future.

  19. Electrochemical studies at high pressure

    SciTech Connect

    Cruanes, M.T.

    1993-01-01

    This research has dealt with the development and application of a methodology that permits electrochemical measurements at high pressure. The initial efforts focused on the design and construction of an electrochemical cell functional at hydrostatic pressures as high as 10 kbar. This cell was equipped with an Ag/AgCl/KCl (0.1M) reference electrode which provides reliable control of the potential at all pressures. The potential of this reference electrode can be considered to be constant with pressure. Measurements of formal potentials (E[degrees][prime]) of several transition-metal complexes vs the Ag/AgCl electrode rendered volumes of reactions whose magnitudes support the prediction of the negligible pressure dependence of the reference electrode. The main systems that have been investigated at high pressure are surface-modified electrodes. The author studied the effect of compression on the dynamics of charge transport in quaternized poly(4-vinylpyridine) (QPVP) films placed on gold electrodes, loaded with potassium ferricyanide, and equilibrated in potassium nitrate. Pressure accomplished the continuous change in the structure of the polymer network. This change causes a pronounced restriction in the propagation of charge and in the motion of mass. This high-pressure methodology has also allowed the spatial characterization of electron transfer events taking place between a gold electrode and ferrocene molecules covalently attached to the end of 1-undodecanethiol chains self-assembled on the electrode surface. The volumes of reaction and activation for the oxidation process are both positive, indicating that a volume expansion is associated with the formation of ferricinium. A model is proposed in which the creation of a vacancy in the self-assembled monolayer, for the accommodation of the ferricinium ion or a charge-compensating anion, is coupled with the electron transfer step.

  20. 46 CFR 169.735 - Fire hose stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Fire hose stations. 169.735 ...SAILING SCHOOL VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.735 Fire hose stations. Each fire hydrant must be identified...

  1. 46 CFR 105.35-15 - Fire hose.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Fire Extinguishing Equipment § 105.35-15 Fire hose. (a) One length of fire hose shall be...

  2. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...hose-to-fitting connection to a 200 pound axial load; and (ii) Passing a visual examination for evidence of separation, slippage, or other damage to the assembly; (3) Each breathing supply hose is periodically checked for— (i) Damage...

  3. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...hose-to-fitting connection to a 200 pound axial load; and (ii) Passing a visual examination for evidence of separation, slippage, or other damage to the assembly; (3) Each breathing supply hose is periodically checked for— (i) Damage...

  4. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...hose-to-fitting connection to a 200 pound axial load; and (ii) Passing a visual examination for evidence of separation, slippage, or other damage to the assembly; (3) Each breathing supply hose is periodically checked for— (i) Damage...

  5. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...hose-to-fitting connection to a 200 pound axial load; and (ii) Passing a visual examination for evidence of separation, slippage, or other damage to the assembly; (3) Each breathing supply hose is periodically checked for— (i) Damage...

  6. 46 CFR 197.456 - Breathing supply hoses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...hose-to-fitting connection to a 200 pound axial load; and (ii) Passing a visual examination for evidence of separation, slippage, or other damage to the assembly; (3) Each breathing supply hose is periodically checked for— (i) Damage...

  7. High pressure neon arc lamp

    DOEpatents

    Sze, Robert C.; Bigio, Irving J.

    2003-07-15

    A high pressure neon arc lamp and method of using the same for photodynamic therapies is provided. The high pressure neon arc lamp includes a housing that encloses a quantity of neon gas pressurized to about 500 Torr to about 22,000 Torr. At each end of the housing the lamp is connected by electrodes and wires to a pulse generator. The pulse generator generates an initial pulse voltage to breakdown the impedance of the neon gas. Then the pulse generator delivers a current through the neon gas to create an electrical arc that emits light having wavelengths from about 620 nanometers to about 645 nanometers. A method for activating a photosensitizer is provided. Initially, a photosensitizer is administered to a patient and allowed time to be absorbed into target cells. Then the high pressure neon arc lamp is used to illuminate the target cells with red light having wavelengths from about 620 nanometers to about 645 nanometers. The red light activates the photosensitizers to start a chain reaction that may involve oxygen free radicals to destroy the target cells. In this manner, a high pressure neon arc lamp that is inexpensive and efficiently generates red light useful in photodynamic therapy is provided.

  8. 46 CFR 35.35-4 - Insulating flange joint or nonconductive hose-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...nonconductive hose—TB/ALL. (a) A vessel's cargo hose string or vapor recovery hose must use an insulating flange or...transfer facility. For each vapor recovery hose or cargo hose string, only one insulating flange or non-conductive hose...

  9. 46 CFR 35.35-4 - Insulating flange joint or nonconductive hose-TB/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...nonconductive hose—TB/ALL. (a) A vessel's cargo hose string or vapor recovery hose must use an insulating flange or...transfer facility. For each vapor recovery hose or cargo hose string, only one insulating flange or non-conductive hose...

  10. 46 CFR 105.35-15 - Fire hose.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...of not over 11/2 -inch diameter or garden hose of not less than 5/8 -inch...027-6 of this chapter. (d) If garden hose is used, it shall be of a good...and shall be fitted with a commercial garden hose nozzle of good grade bronze or...

  11. 46 CFR 105.35-15 - Fire hose.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...of not over 11/2 -inch diameter or garden hose of not less than 5/8 -inch...027-6 of this chapter. (d) If garden hose is used, it shall be of a good...and shall be fitted with a commercial garden hose nozzle of good grade bronze or...

  12. 33 CFR 127.1102 - Transfer hoses and loading arms.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Transfer hoses and loading arms. 127.1102 Section 127.1102 ...127.1102 Transfer hoses and loading arms. (a) Each hose within the marine transfer...service temperature. (b) Each loading arm used for the transfer of LHG or its...

  13. 33 CFR 127.1102 - Transfer hoses and loading arms.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Transfer hoses and loading arms. 127.1102 Section 127.1102 ...127.1102 Transfer hoses and loading arms. (a) Each hose within the marine transfer...service temperature. (b) Each loading arm used for the transfer of LHG or its...

  14. 33 CFR 127.1102 - Transfer hoses and loading arms.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Transfer hoses and loading arms. 127.1102 Section 127.1102 ...127.1102 Transfer hoses and loading arms. (a) Each hose within the marine transfer...service temperature. (b) Each loading arm used for the transfer of LHG or its...

  15. 33 CFR 127.1102 - Transfer hoses and loading arms.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Transfer hoses and loading arms. 127.1102 Section 127.1102 ...127.1102 Transfer hoses and loading arms. (a) Each hose within the marine transfer...service temperature. (b) Each loading arm used for the transfer of LHG or its...

  16. Ernst von Wolzogen Die Gloria-Hose

    E-print Network

    Prodinger, Helmut

    Ernst von Wolzogen Die Gloria-Hose Eine Thüringische Pastoralgeschichte »Frau! Frau!« rief der gekommen ­ vom hohen Kirchenregiment.« Die Frau Pfarrerin stand eben am Waschfaß und wusch die Windeln des bist ja ganz blaß!« rief die Frau und stützte ihre derben Fäuste auf den Tisch, indem sie sich zu ihrem

  17. Stroke and High Blood Pressure

    MedlinePLUS

    ... hurts the brain's ability to think and control body functions. Strokes can affect language, memory and vision as well as cause paralysis and other health issues. How does high blood pressure cause a stroke? ... can damage arteries throughout the body. Weakened arteries in the brain put you at ...

  18. Evaluation of Hose in Hose Transfer Line Service Life for Hanford's Interim Stabilization Program

    SciTech Connect

    TORRES, T.D.

    2000-08-24

    RPP-6153, Engineering Task Plan for Hose-in-Hose Transfer System for the Interim Stabilization Program, defines the programmatic goals, functional requirements, and technical criteria for the development and subsequent installation of transfer line equipment to support Hanford's Interim Stabilization Program. RPP-6028, Specification for Hose in Hose Transfer Lines for Hanford's Interim Stabilization Program, has been issued to define the specific requirements for the design, manufacture, and verification of transfer line assemblies for specific waste transfer applications. Included in RPP-6028 are tables defining the chemical constituents of concern to which transfer lines will be exposed. Current Interim Stabilization Program planning forecasts that the at-grade transfer lines will be required to convey pumpable waste for as much as three years after commissioning. Prudent engineering dictates that the equipment placed in service have a working life in excess of this forecasted time period, with some margin to allow for future adjustments to the planned schedule. This document evaluates the effective service life of the Hose-in-Hose Transfer Lines, based on information submitted by the manufacturer and published literature. The effective service life of transfer line assemblies is a function of several factors. Foremost among these are process fluid characteristics, ambient environmental conditions, and the manufacturer's stated shelf life. This evaluation examines the manufacturer's certification of shelf life, the manufacturer's certifications of chemical compatibility with waste, and published literature on the effects of exposure to ionizing radiation on the mechanical properties of elastomeric materials to evaluate transfer line service life.

  19. High pressure well perforation cleaning

    SciTech Connect

    Buell, R.S.

    1991-10-29

    This patent describes an apparatus for jet washing perforation tunnels in a well casing or liner positioned in a well and perforation tunnels in an adjacent geologic formation. It comprises a tubing means forming a well flow path from the earth's surface to a location adjacent to the well liner positioned in the well; conduit means connecting a source of high pressure liquid to the tubing means, jet tool means having at least one hole in the wall thereof for jetting the high pressure liquid at the perforation tunnels in the well casing or liner, the jet tool means comprising a tubular member connected to the lower end of the tubing means; a jet seat member fixedly connected to the tubular member, the jet seat member having a central opening aligned with the hole and a jet body having a central opening at least 3/23 inch in diameter formed therein hydraulically sealed in the jet seat member, whereby the jet body may be rotated to provide axial movement of the jet body with respect to the jet seat member; and a source of high pressure liquid able to provide a hydraulic horsepower for supplying liquid at a flow rate of at least 0.77 barrels per minute per jet body used at pressures in excess of 5,000 psi, to wash the perforated tunnel to a standoff distance of at least 12 times the diameter of the central opening of the jet body.

  20. High pressure and high temperature apparatus

    DOEpatents

    Voronov, Oleg A.

    2005-09-13

    A design for high pressure/high temperature apparatus and reaction cell to achieve .about.30 GPa pressure in .about.1 cm volume and .about.100 GPa pressure in .about.1 mm volumes and 20-5000.degree. C. temperatures in a static regime. The device includes profiled anvils (28) action on a reaction cell (14, 16) containing the material (26) to be processed. The reaction cell includes a heater (18) surrounded by insulating layers and screens. Surrounding the anvils are cylindrical inserts and supporting rings (30-48) whose hardness increases towards the reaction cell. These volumes may be increased considerably if applications require it, making use of presses that have larger loading force capability, larger frames and using larger anvils.

  1. High pressure processing for food safety

    Microsoft Academic Search

    M. Fonberg-Broczek; B. Windyga; Jacek Szczawi?ski; M. Szczawi?ska; D. Pietrzak; G. Prestamo

    Food preservation using high pressure is a promising technique in food industry as it offers nu- merous opportunities for developing new foods with extended shelf-life, high nutritional value and excellent organoleptic characteristics. High pressure is an alternative to thermal processing. The resistance of microorganisms to pressure varies considerably depending on the pressure range applied, temperature and treatment duration, and type

  2. High pressure space suit glove

    NASA Technical Reports Server (NTRS)

    Elkins, W.

    1973-01-01

    The High Pressure Space Suit Glove Program yielded one prototype glove assembly with an operating pressure of 8.0 psi. The following developments are reported: (1) A new layup technique for incorporation of the mini-convolute systems; (2) modification in the mini-convolute construction to assure cycle life at 8.0 psi in excess of 100,000 cycles; (3) the development of a unique non-orthogonal low torque wrist joint; (4) the development of a low torque single axis joint for use in the thumb and finger first metacarpal joints; and (5) a number of approaches to 1st metacarpal joints were fabricated and tested to establish the joint technqiues.

  3. High Pressure Electrolyzer System Evaluation

    NASA Technical Reports Server (NTRS)

    Prokopius, Kevin; Coloza, Anthony

    2010-01-01

    This report documents the continuing efforts to evaluate the operational state of a high pressure PEM based electrolyzer located at the NASA Glenn Research Center. This electrolyzer is a prototype system built by General Electric and refurbished by Hamilton Standard (now named Hamilton Sunstrand). It is capable of producing hydrogen and oxygen at an output pressure of 3000 psi. The electrolyzer has been in storage for a number of years. Evaluation and testing was performed to determine the state of the electrolyzer and provide an estimate of the cost for refurbishment. Pressure testing was performed using nitrogen gas through the oxygen ports to ascertain the status of the internal membranes and seals. It was determined that the integrity of the electrolyzer stack was good as there were no appreciable leaks in the membranes or seals within the stack. In addition to the integrity testing, an itemized list and part cost estimate was produced for the components of the electrolyzer system. An evaluation of the system s present state and an estimate of the cost to bring it back to operational status was also produced.

  4. Improved high pressure turbine shroud

    NASA Technical Reports Server (NTRS)

    Bessen, I. I.; Rigney, D. V.; Schwab, R. C.

    1977-01-01

    A new high pressure turbine shroud material has been developed from the consolidation of prealloyed powders of Ni, Cr, Al and Y. The new material, a filler for cast turbine shroud body segments, is called Genaseal. The development followed the identification of oxidation resistance as the primary cause of prior shroud deterioration, since conversion to oxides reduces erosion resistance and increases spalling under thermal cycled engine conditions. The NICrAlY composition was selected in preference to NIAL and FeCRALY alloys, and was formulated to a prescribed density range that offers suitable erosion resistance, thermal conductivity and elastic modulus for improved behavior as a shroud.

  5. Brillouin scattering at high pressures

    SciTech Connect

    Grimsditch, M.; Polian, A.

    1988-02-01

    Technical advances which have made Brillouin scattering a useful tool in high pressure diamond anvil cell (DAC) studies, viz. multipassing and tandem operation of Fabry-Perot interferometers, are reviewed. Experimental aspects, such as allowed scattering geometries, are outlined and the data analysis required to transform Brillouin spectra into sound velocities and elastic constants is presented. Experimental results on H/sub 2/, N/sub 2/, Ar, and He are presented, and the close relationship between the Brillouin scattering results and equations of state is highlighted.

  6. Electokinetic high pressure hydraulic system

    DOEpatents

    Paul, Phillip H. (Livermore, CA); Rakestraw, David J. (Fremont, CA)

    2000-01-01

    A compact high pressure hydraulic system having no moving parts for converting electric potential to hydraulic force and for manipulating fluids. Electro-osmotic flow is used to provide a valve and means to compress a fluid or gas in a capillary-based system. By electro-osmotically moving an electrolyte between a first position opening communication between a fluid inlet and outlet and a second position closing communication between the fluid inlet and outlet the system can be configured as a valve. The system can also be used to generate forces as large as 2500 psi that can be used to compress a fluid, either a liquid or a gas.

  7. Nano Materials Under High Pressures

    SciTech Connect

    Karmakar, S.; Garg, Nandini; Sharma, Surinder M. [High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2010-12-01

    Materials comprising of units or particles of the size of a few nano-meters have significantly different high pressure behavior than their bulk counterparts. This is abundantly elucidated in our studies on transition metals encapsulated in carbon nanotubes. Carbon nanotubes filled with Argon also show that it affects the behavior of tubes as well as argon. Studies on nano-crystalline Si displays an interesting crystalline-amorphous reversible transition, unique of its kind in elemental solids. We also demonstrate that in some cases of nanocrystalline samples, a phase perceived to be an intermediate-transient may be actually realized.

  8. Electrical Transport Experiments at High Pressure

    SciTech Connect

    Weir, S

    2009-02-11

    High-pressure electrical measurements have a long history of use in the study of materials under ultra-high pressures. In recent years, electrical transport experiments have played a key role in the study of many interesting high pressure phenomena including pressure-induced superconductivity, insulator-to-metal transitions, and quantum critical behavior. High-pressure electrical transport experiments also play an important function in geophysics and the study of the Earth's interior. Besides electrical conductivity measurements, electrical transport experiments also encompass techniques for the study of the optoelectronic and thermoelectric properties of materials under high pressures. In addition, electrical transport techniques, i.e., the ability to extend electrically conductive wires from outside instrumentation into the high pressure sample chamber have been utilized to perform other types of experiments as well, such as high-pressure magnetic susceptibility and de Haas-van Alphen Fermi surface experiments. Finally, electrical transport techniques have also been utilized for delivering significant amounts of electrical power to high pressure samples, for the purpose of performing high-pressure and -temperature experiments. Thus, not only do high-pressure electrical transport experiments provide much interesting and valuable data on the physical properties of materials extreme compression, but the underlying high-pressure electrical transport techniques can be used in a number of ways to develop additional diagnostic techniques and to advance high pressure capabilities.

  9. HIGH PRESSURE CRYOCOOLING FOR MACROMOLECULAR CRYSTALLOGRAPHY

    E-print Network

    Gruner, Sol M.

    HIGH PRESSURE CRYOCOOLING FOR MACROMOLECULAR CRYSTALLOGRAPHY A Dissertation Presented CRYOCOOLING FOR MACROMOLECULAR CRYSTALLOGRAPHY Chae Un Kim, Ph. D. Cornell University 2008 A novel high-pressure cryocooling technique to reduce radiation damage in macromolecular crystallography is developed and explored

  10. Low-Pressure Wellhead for High-Pressure Stimulation

    Microsoft Academic Search

    Tom Garvin

    1994-01-01

    Maturity of US Producing wells and constrained economics dictate careful planning and strict attention to details to optimize workover and recompletion operations. One aspect of operations that can significantly reduce costs is planned preparation of a wellheat for high-pressure stimulation. Historically, there have been four basic approaches to solving old wellhead configuration problems to prepare for high-pressure stimulation down casing.

  11. Optical calibration of pressure sensors for high pressures and temperatures

    SciTech Connect

    Goncharov, A F; Gregoryanz, E; Zaug, J M; Crowhurst, J C

    2004-10-04

    We present the results of Raman scattering measurements of diamond ({sup 12}C) and of cubic boron nitride (cBN), and fluorescence measurements of ruby, Sm:YAG, and SrB{sub 4}O{sub 7}:Sm{sup 2+} in the diamond anvil cell (DAC) at high pressures and temperatures. These measurements were accompanied by synchrotron x-ray diffraction measurements on gold. We have extended the room-temperature calibration of Sm:YAG in a quasihydrostatic regime up to 100 GPa. The ruby scale is shown to systematically underestimate pressure at high pressures and temperatures compared with all other sensors. On this basis, we propose a new high-temperature ruby pressure scale that should be valid to at least 100 GPa and 850 K. Historically, the accurate determination of pressure at high temperature and ultrahigh pressure has been extremely difficult. In fact, the lack of a general pressure scale nullifies, to a significant extent, the great innovations that have been made in recent years in DAC experimental techniques [1]. Now, more than ever a scale is required whose accuracy is comparable with that of the experimental data. Since pressure in the DAC is dependent on temperature (due to thermal pressure and also to changes in the properties of the materials that constitute the DAC) such a scale requires quantitative, and separate measurements of pressure and temperature.

  12. National High Blood Pressure Education Program Prevention,

    E-print Network

    Bandettini, Peter A.

    National High Blood Pressure Education Program Prevention, Detection, Evaluation, and Treatment of High Blood Pressure The Seventh Report of the Joint National Committee on Complete Report U . S . D E Institutes of Health National Heart, Lung, and Blood Institute National High Blood Pressure Education Program

  13. High-pressure microhydraulic actuator

    DOEpatents

    Mosier, Bruce P. (San Francisco, CA) [San Francisco, CA; Crocker, Robert W. (Fremont, CA) [Fremont, CA; Patel, Kamlesh D. (Dublin, CA) [Dublin, CA

    2008-06-10

    Electrokinetic ("EK") pumps convert electric to mechanical work when an electric field exerts a body force on ions in the Debye layer of a fluid in a packed bed, which then viscously drags the fluid. Porous silica and polymer monoliths (2.5-mm O.D., and 6-mm to 10-mm length) having a narrow pore size distribution have been developed that are capable of large pressure gradients (250-500 psi/mm) when large electric fields (1000-1500 V/cm) are applied. Flowrates up to 200 .mu.L/min and delivery pressures up to 1200 psi have been demonstrated. Forces up to 5 lb-force at 0.5 mm/s (12 mW) have been demonstrated with a battery-powered DC-DC converter. Hydraulic power of 17 mW (900 psi@ 180 uL/min) has been demonstrated with wall-powered high voltage supplies. The force and stroke delivered by an actuator utilizing an EK pump are shown to exceed the output of solenoids, stepper motors, and DC motors of similar size, despite the low thermodynamic efficiency.

  14. Active Hose: an Artificial Elephant's Nose with Maneuverability for Rescue Operation

    Microsoft Academic Search

    Hideyuki Tsukagoslii; Ato Kitagawa; Mitsuru Segawa

    2001-01-01

    Proposes both the design concept and the driving mechanism of a flexible robot with multiple degrees of freedom to dive into debris. Up to now, several kinds of pneumatic robots with flexibility have been developed, however, they could not perform multiple degrees of freedom with high bending moment. A new type of robot, called Active Hose, is proposed which has

  15. 49 CFR 178.348-3 - Pumps, piping, hoses and connections.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 2014-10-01 false Pumps, piping, hoses and connections. 178.348-3...Motor Vehicle Transportation § 178.348-3 Pumps, piping, hoses and connections. Each pump and all piping, hoses and connections...

  16. 49 CFR 178.348-3 - Pumps, piping, hoses and connections.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 2013-10-01 false Pumps, piping, hoses and connections. 178.348-3...Motor Vehicle Transportation § 178.348-3 Pumps, piping, hoses and connections. Each pump and all piping, hoses and connections...

  17. 49 CFR 178.348-3 - Pumps, piping, hoses and connections.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 2010-10-01 2010-10-01 false Pumps, piping, hoses and connections. 178.348-3...Motor Vehicle Transportation § 178.348-3 Pumps, piping, hoses and connections. Each pump and all piping, hoses and connections...

  18. 49 CFR 178.348-3 - Pumps, piping, hoses and connections.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 2011-10-01 2011-10-01 false Pumps, piping, hoses and connections. 178.348-3...Motor Vehicle Transportation § 178.348-3 Pumps, piping, hoses and connections. Each pump and all piping, hoses and connections...

  19. Manufacturing Diamond Under Very High Pressure

    NASA Technical Reports Server (NTRS)

    Voronov, Oleg

    2007-01-01

    A process for manufacturing bulk diamond has been made practical by the invention of the High Pressure and Temperature Apparatus capable of applying the combination of very high temperature and high pressure needed to melt carbon in a sufficiently large volume. The apparatus includes a reaction cell wherein a controlled static pressure as high as 20 GPa and a controlled temperature as high as 5,000 C can be maintained.

  20. Optically accessible high-pressure combustion apparatus

    Microsoft Academic Search

    Stephen D. Tse; Delin Zhu; Chung K. Law

    2004-01-01

    The design and operation of a novel optically accessible high-pressure combustion apparatus is presented. The apparatus provides optical access for the direct observation of the morphology and development of premixed reaction fronts at elevated pressures. A chamber-in-chamber design with an innovative connecting system allows for safe, constant-pressure measurements, alleviating the extreme overpressures encountered in high-pressure combustion processes within closed bombs.

  1. 46 CFR 118.320 - Fire hoses and nozzles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Shipping 4 2010-10-01 2010-10-01 false Fire hoses and nozzles. 118.320 Section 118.320...OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fire Main System § 118.320 Fire hoses and...

  2. 46 CFR 108.425 - Fire hoses and associated equipment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Shipping 4 2010-10-01 2010-10-01 false Fire hoses and associated equipment. 108.425 Section...A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Main System § 108.425 Fire hoses and...

  3. 46 CFR 118.320 - Fire hoses and nozzles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Shipping 4 2011-10-01 2011-10-01 false Fire hoses and nozzles. 118.320 Section 118.320...OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fire Main System § 118.320 Fire hoses and...

  4. 46 CFR 108.425 - Fire hoses and associated equipment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Shipping 4 2011-10-01 2011-10-01 false Fire hoses and associated equipment. 108.425 Section...A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Main System § 108.425 Fire hoses and...

  5. Optical calibration of pressure sensors for high pressures and temperatures

    SciTech Connect

    Goncharov, Alexander F.; Zaug, Joseph M.; Crowhurst, Jonathan C.; Gregoryanz, Eugene [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94551 (United States); Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road, Northwest, Washington DC 20015 (United States)

    2005-05-01

    We present the results of Raman-scattering measurements of diamond ({sup 12}C) and of cubic boron nitride, and fluorescence measurements of ruby, Sm:yttrium aluminum garnet (Sm:YAG), and SrB{sub 4}O{sub 7}:Sm{sup 2+} in the diamond anvil cell at high pressures and temperatures. These measurements were accompanied by synchrotron x-ray-diffraction measurements on gold. We have extended the room-temperature calibration of Sm:YAG in a quasihydrostatic regime up to 100 GPa. The ruby scale is found to systematically underestimate pressure at high pressures and temperatures compared with all the other sensors. On this basis, we propose an alternative high-temperature ruby pressure scale that is valid to at least 100 GPa and 850 K.

  6. High pressure synthesis gas conversion. Final report

    SciTech Connect

    Not Available

    1993-05-01

    The purpose of this research project is to build and test a high pressure fermentation system for the production of ethanol from synthesis gas. The fermenters, pumps, controls, and analytical system were procured or fabricated and assembled in our laboratory. This system was then used to determine the effects of high pressure on growth and ethanol production by Clostridium ljungdahlii. The limits of cell concentration and mass transport relationships were found in CSTR and immobilized cell reactors (ICR). The minimum retention times and reactor volumes were found for ethanol production in these reactors. A maximum operating pressure of 150 psig has been shown to be possible for C. ljungdahlli with the medium of Phillips et al. This medium was developed for atmospheric pressure operation in the CSTR to yield maximum ethanol concentrations and thus is not best for operation at elevated pressures. It is recommended that a medium development study be performed for C. ljungdahlii at increased pressure. Cell concentration, gas conversion and product concentration profiles were presented for C. ljungdahlii as a function of gas flow rate, the variable which affects bacterium performance the most. This pressure was chosen as a representative pressure over the 0--150 psig operating pressure range for the bacterium. Increased pressure negatively affected ethanol productivity probably due to the fact that medium composition was designed for atmospheric pressure operation. Medium development at increased pressure is necessary for high pressure development of the system.

  7. Iodine pressure in high intensity discharge lamps

    NASA Astrophysics Data System (ADS)

    Dunaevsky, Alexander; Tu, Jun-Ming

    2008-10-01

    The dynamics of the partial pressure of iodine influence the emission properties of metal halide lamps. In addition, various processes in the discharge affect the iodine pressure. Monitoring the partial pressure of iodine by high-resolution spectroscopy (HRS) can be a very powerful, non-destructive diagnostic tool for metal halide lamp development, if the mechanisms responsible for the pressure changes are understood. Thermodynamic modeling can help to interpret some effects observed experimentally. In this study, the iodine pressure in quartz sodium-scandium metal halide lamps with various chemical additive ratios is measured using the HRS technique. The correlations between partial pressures predicted by modeling and observed experimentally are analyzed.

  8. High Precision Pressure Measurement with a Funnel

    ERIC Educational Resources Information Center

    Lopez-Arias, T.; Gratton, L. M.; Oss, S.

    2008-01-01

    A simple experimental device for high precision differential pressure measurements is presented. Its working mechanism recalls that of a hydraulic press, where pressure is supplied by insufflating air under a funnel. As an application, we measure air pressure inside a soap bubble. The soap bubble is inflated and connected to a funnel which is…

  9. New materials from high-pressure experiments

    Microsoft Academic Search

    Paul F. McMillan

    2002-01-01

    High-pressure synthesis on an industrial scale is applied to obtain synthetic diamonds and cubic boron nitride (c-BN), which are the superhard abrasives of choice for cutting and shaping hard metals and ceramics. Recently, high-pressure science has undergone a renaissance, with novel techniques and instrumentation permitting entirely new classes of high-pressure experiments. For example, superconducting behaviour was previously known for only

  10. NETL- High-Pressure Combustion Research Facility

    ScienceCinema

    None

    2014-06-26

    NETL's High-Pressure Combustion Facility is a unique resource within the National Laboratories system. It provides the test capabilities needed to evaluate new combustion concepts for high-pressure, high-temperature hydrogen and natural gas turbines. These concepts will be critical for the next generation of ultra clean, ultra efficient power systems.

  11. NETL- High-Pressure Combustion Research Facility

    SciTech Connect

    None

    2013-07-08

    NETL's High-Pressure Combustion Facility is a unique resource within the National Laboratories system. It provides the test capabilities needed to evaluate new combustion concepts for high-pressure, high-temperature hydrogen and natural gas turbines. These concepts will be critical for the next generation of ultra clean, ultra efficient power systems.

  12. What Causes High Blood Pressure?

    MedlinePLUS

    ... pressure - a hypertension Google+ hangout in honor of World Hypertension Day 04/18/2013 Moderated by American ... live on April 5, 2013 in honor of World Health Day on Sunday, April 7. The NHLBI " ...

  13. Living with High Blood Pressure

    MedlinePLUS

    ... pressure - a hypertension Google+ hangout in honor of World Hypertension Day 04/18/2013 Moderated by American ... live on April 5, 2013 in honor of World Health Day on Sunday, April 7. The NHLBI " ...

  14. High pressure processing for food safety.

    PubMed

    Fonberg-Broczek, Monika; Windyga, B; Szczawi?ski, J; Szczawi?ska, M; Pietrzak, D; Prestamo, G

    2005-01-01

    Food preservation using high pressure is a promising technique in food industry as it offers numerous opportunities for developing new foods with extended shelf-life, high nutritional value and excellent organoleptic characteristics. High pressure is an alternative to thermal processing. The resistance of microorganisms to pressure varies considerably depending on the pressure range applied, temperature and treatment duration, and type of microorganism. Generally, Gram-positive bacteria are more resistant to pressure than Gram-negative bacteria, moulds and yeasts; the most resistant are bacterial spores. The nature of the food is also important, as it may contain substances which protect the microorganism from high pressure. This article presents results of our studies involving the effect of high pressure on survival of some pathogenic bacteria -- Listeria monocytogenes, Aeromonas hydrophila and Enterococcus hirae -- in artificially contaminated cooked ham, ripening hard cheese and fruit juices. The results indicate that in samples of investigated foods the number of these microorganisms decreased proportionally to the pressure used and the duration of treatment, and the effect of these two factors was statistically significant (level of probability, P high pressure treatment than L. monocytogenes and A. hydrophila. Mathematical methods were applied, for accurate prediction of the effects of high pressure on microorganisms. The usefulness of high pressure treatment for inactivation of microorganisms and shelf-life extention of meat products was also evaluated. The results obtained show that high pressure treatment extends the shelf-life of cooked pork ham and raw smoked pork loin up to 8 weeks, ensuring good micro-biological and sensory quality of the products. PMID:16175246

  15. Diaphragm based high sensitive FBG pressure sensor

    NASA Astrophysics Data System (ADS)

    Vengal Rao, P.; Srimannarayana, K.; Sai Shankar, M.; Kishore, P.

    2013-06-01

    A high sensitive pressure sensor based on Fiber Bragg grating (FBG) integrated with a thin metal diaphragm was designed and demonstrated. To enhance the pressure sensitivity FBG is firmly glued across the diameter of the diaphragm. Under pressure, the diaphragm deforms and produces an induced strain along the length of the fiber causes shift in Bragg wavelength of the FBG. Pressure measurement is made by measuring the Bragg wavelength shift against change in pressure. The sensor was tested up to the maximum pressure of 140 psi and the corresponding pressure sensitivity was found to be 0.0204 nm/psi, which is approximately 970 times higher than that can be achieved with a bare FBG. The experimental results show good agreement with the theoretical results and possess good linearity and repeatability. This sensor can be used for the measurement of medium pressure, liquid level and depth of underwater.

  16. Zirconate pyrochlores under high pressure

    SciTech Connect

    Xiao, Haiyan Y.; Zhang, F. X.; Gao, Fei; Lang, Maik; Ewing, Rodney C.; Weber, William J.

    2010-07-12

    Ab initio total-energy calculations and x-ray diffraction measurements have been combined to study the phase stability of zirconate pyrochlores (A2Zr2O7; A=La, Nd and Sm) under pressures up to 50 GPa. Phase transformations to the defect-cotunnite structure are theoretically predicted at pressures of 22, 20 and 18 GPa, in excellent agreement with the experimentally determined values of 21, 22 and 18 GPa for La2Zr2O7, Nd2Zr2O7 and Sm2Zr2O7, respectively. Analysis of the elastic properties indicates that elastic anisotropy may be one of the driving forces for the pressure-induced cubic-to-noncubic phase transformation.

  17. Multicomponent fuel vaporization at high pressures.

    SciTech Connect

    Torres, D. J. (David J.); O'Rourke, P. J. (Peter J.)

    2002-01-01

    We extend our multicomponent fuel model to high pressures using a Peng-Robinson equation of state, and implement the model into KIVA-3V. Phase equilibrium is achieved by equating liquid and vapor fugacities. The latent heat of vaporization and fuel enthalpies are also corrected for at high pressures. Numerical simulations of multicomponent evaporation are performed for single droplets for a diesel fuel surrogate at different pressures.

  18. Life of Artemia under very high pressure

    Microsoft Academic Search

    F. Ono; K. Minami; M. Saigusa; Y. Matsushima; Y. Mori; K. Takarabe; N. L. Saini; M. Yamashita

    2010-01-01

    The experiment on the search for life under very high pressure done for small animal tardigrades has been extended to a plankton, Artemia. It was found that cysts, or dried eggs, of Artemia remain alive after being exposed to a very high hydrostatic pressure of 7.5GPa for 42h. We are convinced that at least two kinds of small animals are

  19. High Blood Pressure - Multiple Languages: MedlinePlus

    MedlinePLUS

    ... Blood Pressure (Arabic) ??????? Bilingual PDF Health Information Translations Bosnian (Bosanski) High Blood Pressure Visoki krvni tlak - Bosanski (Bosnian) Bilingual PDF Health Information Translations Chinese - Simplified (????) High Blood Pressure ??? - ???? ( ...

  20. Laser techniques in high-pressure geophysics

    NASA Technical Reports Server (NTRS)

    Hemley, R. J.; Bell, P. M.; Mao, H. K.

    1987-01-01

    Laser techniques in conjunction with the diamond-anvil cell can be used to study high-pressure properties of materials important to a wide range of problems in earth and planetary science. Spontaneous Raman scattering of crystalline and amorphous solids at high pressure demonstrates that dramatic changes in structure and bonding occur on compression. High-pressure Brillouin scattering is sensitive to the pressure variations of single-crystal elastic moduli and acoustic velocities. Laser heating techniques with the diamond-anvil cell can be used to study phase transitions, including melting, under deep-earth conditions. Finally, laser-induced ruby fluorescence has been essential for the development of techniques for generating the maximum pressures now possible with the diamond-anvil cell, and currently provides a calibrated in situ measure of pressure well above 100 gigapascals.

  1. Optically accessible high-pressure combustion apparatus

    NASA Astrophysics Data System (ADS)

    Tse, Stephen D.; Zhu, Delin; Law, Chung K.

    2004-01-01

    The design and operation of a novel optically accessible high-pressure combustion apparatus is presented. The apparatus provides optical access for the direct observation of the morphology and development of premixed reaction fronts at elevated pressures. A chamber-in-chamber design with an innovative connecting system allows for safe, constant-pressure measurements, alleviating the extreme overpressures encountered in high-pressure combustion processes within closed bombs. Auxiliary design features include gap-adjustable electrodes for spark ignition and ports for jet stirring. As a result, the apparatus is well suited for the study of laminar premixed flames, flame instabilities, turbulent flames, and detonations. Results from the study of centrally ignited hydrogen and methane fuels in oxygen-inert mixtures up to 60 atm initial pressure demonstrate the suitability of the apparatus for high-pressure combustion experiments.

  2. A temperature compensated pressure transducer for high temperature, high pressure applications

    E-print Network

    Lippka, Sandra Margaret

    1991-01-01

    A TEMPERATURE COMPENSATED PRESSURE TRANSDUCER FOR HIGH TEMPERATURE, HIGH PRESSURE APPLICATIONS A Thesis by SANDRA MARGARET LIPPKA Submitted to the OIIice of Graduate Studies ol' Texas A8;M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE May 1991 Major Subject; Mechanical Engineering A TEMPERATURE COMPENSATED PRESSURE TRANSDUCER FOR HIGH TEMPERATURE, HIGH PRESSURE APPLICATIONS A Thes&s SAiVDRA MARGARET LIPPKA Approved as to style...

  3. High-resolution, high-pressure NMR studies of proteins.

    PubMed Central

    Jonas, J; Ballard, L; Nash, D

    1998-01-01

    Advanced high-resolution NMR spectroscopy, including two-dimensional NMR techniques, combined with high pressure capability, represents a powerful new tool in the study of proteins. This contribution is organized in the following way. First, the specialized instrumentation needed for high-pressure NMR experiments is discussed, with specific emphasis on the design features and performance characteristics of a high-sensitivity, high-resolution, variable-temperature NMR probe operating at 500 MHz and at pressures of up to 500 MPa. An overview of several recent studies using 1D and 2D high-resolution, high-pressure NMR spectroscopy to investigate the pressure-induced reversible unfolding and pressure-assisted cold denaturation of lysozyme, ribonuclease A, and ubiquitin is presented. Specifically, the relationship between the residual secondary structure of pressure-assisted, cold-denatured states and the structure of early folding intermediates is discussed. PMID:9649405

  4. High Pressure Research Questionnaire National High Magnetic Field Laboratory

    E-print Network

    Weston, Ken

    pressure data for this sample or a similar system. These items and the samples should be sent to Stan Tozer, is email, phone, or FAX preferred? #12;High Pressure Questionnaire Contact Dr. Stan Tozer tozer. #12;High Pressure Questionnaire Contact Dr. Stan Tozer tozer@magnet.fsu.edu, (850) 644-33460 for more

  5. PARTICLE COLLECTION IN CYCLONES AT HIGH TEMPERATURE AND HIGH PRESSURE

    EPA Science Inventory

    The paper gives results of an experimental study of cyclone efficiency and pressure drop at temperatures up to 700C and pressures up to 25 atm. The cyclone efficiency was found to decrease at high temperature and increase at high pressure for a constant inlet velocity. Available ...

  6. CHRONOBIOLOGY OF HIGH BLOOD PRESSURE

    PubMed Central

    Cornélissen, G.; Halberg, F.; Bakken, E. E.; Wang, Z.; Tarquini, R.; Perfetto, F.; Laffi, G.; Maggioni, C.; Kumagai, Y.; Homolka, P.; Havelková, A.; Dušek, J.; Sva?inová, H.; Siegelová, J.; Fišer, B.

    2008-01-01

    BIOCOS, the project aimed at studying BIOlogical systems in their COSmos, has obtained a great deal of expertise in the fields of blood pressure (BP) and heart rate (HR) monitoring and of marker rhythmometry for the purposes of screening, diagnosis, treatment, and prognosis. Prolonging the monitoring reduces the uncertainty in the estimation of circadian parameters; the current recommendation of BIOCOS requires monitoring for at least 7 days. The BIOCOS approach consists of a parametric and a non-parametric analysis of the data, in which the results from the individual subject are being compared with gender- and age-specified reference values in health. Chronobiological designs can offer important new information regarding the optimization of treatment by timing its administration as a function of circadian and other rhythms. New technological developments are needed to close the loop between the monitoring of blood pressure and the administration of antihypertensive drugs. PMID:19122770

  7. High pressure Hugoniot of sapphire

    Microsoft Academic Search

    Dave Erskine

    1993-01-01

    The Hugoniot of sapphire was measured from 80 GPa to 340 GPa in shock wave experiments using projectiles accelerated by a two stage gas gun. Transit times of the shock waves were measured either optically with a streak camera or through electrical pin contacts. The Hugoniot in this pressure range fits U(sub s) = 8.74 + 0.96 U(sub p) in

  8. Abnormally high formation pressures, Potwar Plateau, Pakistan

    USGS Publications Warehouse

    Law, B.E.; Shah, S.H.A.; Malik, M.A.

    1998-01-01

    Abnormally high formation pressures in the Potwar Plateau of north-central Pakistan are major obstacles to oil and gas exploration. Severe drilling problems associated with high pressures have, in some cases, prevented adequate evaluation of reservoirs and significantly increased drilling costs. Previous investigations of abnormal pressure in the Potwar Plateau have only identified abnormal pressures in Neogene rocks. We have identified two distinct pressure regimes in this Himalayan foreland fold and thrust belt basin: one in Neogene rocks and another in pre-Neogene rocks. Pore pressures in Neogene rocks are as high as lithostatic and are interpreted to be due to tectonic compression and compaction disequilibrium associated with high rates of sedimentation. Pore pressure gradients in pre-Neogene rocks are generally less than those in Neogene rocks, commonly ranging from 0.5 to 0.7 psi/ft (11.3 to 15.8 kPa/m) and are most likely due to a combination of tectonic compression and hydrocarbon generation. The top of abnormally high pressure is highly variable and doesn't appear to be related to any specific lithologic seal. Consequently, attempts to predict the depth to the top of overpressure prior to drilling are precluded.

  9. Portable high precision pressure transducer system

    DOEpatents

    Piper, T.C.; Morgan, J.P.; Marchant, N.J.; Bolton, S.M.

    1994-04-26

    A high precision pressure transducer system is described for checking the reliability of a second pressure transducer system used to monitor the level of a fluid confined in a holding tank. Since the response of the pressure transducer is temperature sensitive, it is continually housed in an battery powered oven which is configured to provide a temperature stable environment at specified temperature for an extended period of time. Further, a high precision temperature stabilized oscillator and counter are coupled to a single board computer to accurately determine the pressure transducer oscillation frequency and convert it to an applied pressure. All of the components are powered by the batteries which during periods of availability of line power are charged by an on board battery charger. The pressure readings outputs are transmitted to a line printer and a vacuum fluorescent display. 2 figures.

  10. Combustion of liquid sprays at high pressures

    NASA Technical Reports Server (NTRS)

    Shearer, A. J.; Faeth, G. M.

    1977-01-01

    The combustion of pressure atomized fuel sprays in high pressure stagnant air was studied. Measurements were made of flame and spray boundaries at pressures in the range 0.1-9 MPa for methanol and n-pentane. At the higher test pressure levels, critical phenomena are important. The experiments are compared with theoretical predictions based on a locally homogeneous two-phase flow model. The theory correctly predicted the trends of the data, but underestimates flame and spray boundaries by 30-50 percent, indicating that slip is still important for the present experiments (Sauter mean diameters of 30 microns at atmospheric pressure under cold flow conditions). Since the sprays are shorter at high pressures, slip effects are still important even though the density ratio of the phases approach one another as the droplets heat up. The model indicates the presence of a region where condensed water is present within the spray and provides a convenient means of treating supercritical phenomena.

  11. High-pressure mechanical instability in rocks

    USGS Publications Warehouse

    Byerlee, J.D.; Brace, W.F.

    1969-01-01

    At a confining pressure of a few kilobars, deformation of many sedimentary rocks, altered mafic rocks, porous volcanic rocks, and sand is ductile, in that instabilities leading to audible elastic shocks are absent. At pressures of 7 to 10 kilobars, however, unstable faulting and stick-slip in certain of these rocks was observed. This high pressure-low temperature instability might be responsible for earthquakes in deeply buried sedimentary or volcanic sequences.

  12. 29 CFR 1910.158 - Standpipe and hose systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...immediately and replace it with equivalent protection such as extinguishers and fire watches. (v) The employer shall assure that hemp or linen hose on existing systems is unracked, physically inspected for deterioration, and reracked using a different...

  13. 46 CFR 193.10-10 - Fire hydrants and hose.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...may have a garden hose nozzle that is bronze or metal with strength and corrosion resistance equivalent to bronze. Combination solid...shall be of brass, bronze, or other equivalent metal. National Standard firehose coupling threads...

  14. 46 CFR 193.10-10 - Fire hydrants and hose.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...may have a garden hose nozzle that is bronze or metal with strength and corrosion resistance equivalent to bronze. Combination solid...shall be of brass, bronze, or other equivalent metal. National Standard firehose coupling threads...

  15. 46 CFR 193.10-10 - Fire hydrants and hose.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...may have a garden hose nozzle that is bronze or metal with strength and corrosion resistance equivalent to bronze. Combination solid...shall be of brass, bronze, or other equivalent metal. National Standard firehose coupling threads...

  16. 46 CFR 193.10-10 - Fire hydrants and hose.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...may have a garden hose nozzle that is bronze or metal with strength and corrosion resistance equivalent to bronze. Combination solid...shall be of brass, bronze, or other equivalent metal. National Standard firehose coupling threads...

  17. 46 CFR 193.10-10 - Fire hydrants and hose.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...may have a garden hose nozzle that is bronze or metal with strength and corrosion resistance equivalent to bronze. Combination solid...shall be of brass, bronze, or other equivalent metal. National Standard firehose coupling threads...

  18. Inverse estimation of the acoustic impedance of a porous woven hose from measured transmission coefficients.

    PubMed

    Park, Chul-Min; Ih, Jeong-Guon; Nakayama, Yoshio; Takao, Hideo

    2003-01-01

    A porous tube, comprised of a resin-coated woven fabric has recently been used as an effective component for use in intake systems of internal combustion engines to reduce the intake noise. For the prediction of the acoustic performance of an engine intake system with a porous woven hose, the acoustic wall impedance of the hose must be known. However, the accurate measurement of the wall impedance of a porous woven hose is not easy because of its peculiar acoustical and structural characteristics. A new measurement technique is proposed herein, that is valid over the low to mid frequency ranges. The acoustics impedance is inversely estimated from an overdetermined set of measured pressure transmission coefficients for specimens of different lengths and the reflection coefficient of end termination. The method involves only one measurement setup, and, as a result, it is very simple. A variation of the proposed method, an inverse estimation method using one of the four-pole parameters is also proposed. An error sensitivity analysis was performed to investigate the effect of measurement error on the accuracy of the final result. The measured TL for samples with arbitrary lengths and arbitrary porous frequency are in reasonably good agreement with values predicted from curve-fitted impedance data. PMID:12558253

  19. HIGH-TEMPERATURE AND HIGH-PRESSURE PARTICULATE CONTROL REQUIREMENTS

    EPA Science Inventory

    The report reviews and evaluates high-temperature and high-pressure particulate cleanup requirements of existing and proposed energy processes. The study's aims are to define specific high-temperature and high-pressure particle removal problems, to indicate potential solutions, a...

  20. Stable Xenon Nitride at High Pressures

    NASA Astrophysics Data System (ADS)

    Zhang, Yunwei; Peng, Feng; Ma, Yanming

    2015-03-01

    Nitrogen is the most abundant element on Earth and exists as inert N2 molecules in the atmosphere. Noble gas nitrides are missing in nature because N2 molecules do not interact with noble gases at ambient conditions, greatly impeding the understanding of physics and chemistry of such nitrides. We report here a pressure-induced chemical reaction of N2 with xenon predicted using a swarm-structure searching calculation as implemented in the CALYPSO code. This reaction leads to the formation of a hitherto unexpected Xe nitride at megabar pressure accessible to high-pressure experiments. The high-pressure phase with a hypervalent state of Xe by accepting unprecedented Xe-N covalent bonds appears to be the most stable stoichiometry. The Xe bonding situation in this new phase is substantially different from earlier high-pressure examples of ionic Xe bonding or van der Waals interactions.

  1. High temperature vapor pressure of pure plutonium

    Microsoft Academic Search

    M. H. Bradbury; R. W. Ohse

    1979-01-01

    High temperature vapor pressure measurements have been made on pure plutonium metal by the Knudsen effusion technique. The reported experimental results extend into the transition region between molecular and viscous or hydrodynamic flow. Under the conditions used, linearity was observed up to temperatures in excess of 2200 K where pressures approaching 100 Pa were measured. The results over the temperature

  2. Raman Study of SWNT Under High Pressure

    NASA Astrophysics Data System (ADS)

    Venkateswaran, U.; Rao, A. M.; Richter, E.; Eklund, P. C.; Smalley, R. E.

    1998-03-01

    A gasketed Merrill-Bassett-type diamond anvil cell was used for high pressure Raman measurements at room temperature. A 4:1 methanol-ethanol mixture served as the pressure transmitting medium. The radial mode (denoted as R, occuring at 186 cm-1 at 1 bar) and tangential modes (designated T_1, T_2, and T_3, located, respectively, at 1550, 1567, and 1593 cm-1 at 1 bar) were recorded for several representative pressures. With increasing pressure, both the R and T modes shift to higher frequencies with gradual weakening of intensity and broadening of linewidth. The radial mode disappears around ~ 2 GPa whereas the tangential modes, albeit weak in intensity, persist until 5.2 GPa. The decrease in Raman intensity under pressure can be attributed to a loss of resonance, since the strong Raman signals observed at ambient pressure have been interpreted as due a resonance with the electronic bands [1]. The R and T mode frequencies are fit to quadratic function of pressure i.e., ?=?(0)+aP+bP^2 where `a' represents the linear pressure shift of the mode frequency which is proportional to the mode Gruneisen parameter. The linear pressure coefficient for the R mode is found to be nearly twice that of the high frequency T mode. A. M. Rao et al., Science 275, 187, 1997

  3. LESSONS LEARNED IN OPERATING THE HOSE-IN-HOSE SYSTEM FOR TRANSFSERRING SLUDGE AT HANFORDS K-BASINS

    SciTech Connect

    PERES MW

    2008-01-07

    In May 2007, the Department of Energy and the Fluor Hanford K Basin Closure Project completed transferring sludge from the K East Basin to new containers in the K West Basin using a Hose-in-Hose system. This project presented a number of complex and unique technical, operational, and management challenges that had to be resolved to complete the required transfers and satisfy project milestones. The project team (including DOE; regulators; and Fluor management, operations, maintenance, engineering and all other support organizations) found innovative solutions to each challenge. This paper records lessons learned during the operational phase of the sludge transfer via the Hose-In-Hose system. The subject is limited to the operational phase and does not cover design, development, testing or turnover. A discussion of the situation or problem encountered is provided, along with the lesson learned as applicable to a future program or project.

  4. High Blood Pressure: The Science Inside

    NSDL National Science Digital Library

    Healthy People Library Project

    2004-01-01

    This booklet is a resource to help individuals at risk to high blood pressure. Supported by Science Education Partnership Award (SEPA) from the National Center for Research Resources Grant # 5R25RR15601

  5. High Blood Pressure: Unique to Older Adults

    MedlinePLUS

    High Blood Pressure Hypertension Unique to Older Adults This section provides information to help older adults and their caregivers consider their disease or condition in conjunction with other health issues. ...

  6. High-Pressure Protein Crystallography and NMR

    E-print Network

    Gruner, Sol M.

    High-Pressure Protein Crystallography and NMR to Explore Protein Conformations Marcus D. Collins,1 Crystallography. . . . . . . . . . . . . . . . . 87 Conformational Substates of Myglobin. . . . . . . . . . . . . . . . . . . . . . . 88 Energy Landscapes by Crystallography. . . . . . . . . . . . . . . . . 89 A VIEW INTO THE FUTURE

  7. High-pressure studies of ammonia hydrates 

    E-print Network

    Wilson, Craig W.

    2014-06-28

    Ammonia and water are major components of many planetary bodies, from comets and icy moons such as Saturn's Titan to the interiors of the planets Neptune and Uranus. Under a range of high pressures and/or low temperatures known ...

  8. High-pressure polymorphism in phosphorus nitrides

    NASA Astrophysics Data System (ADS)

    Dong, Jianjun

    2002-03-01

    Motivated by the successful discovery of the high-pressure spinel phase in Si3N4 and Ge3N4, we have performed a theoretical exploration of new high-pressure phases of P3N5, a member of group-V(B) nitrides. Guided by crystal chemistry, we have investigated nine representative structure types for P3N5 based on first-principle density functional calculations. In addition to the recently determined alpha and gamma phase, our study predicts two meta-stable high-pressure phases existing in the 5 to 20 GPa range, with structures related to the Al2SiO5 sillimanite and kyanite, and a new thermodynamically stable phase that should form above 25 GPa. By providing new insights on the competitive P-N bonding type at different pressures and on the structural connection between isoelectronic oxides and nitrides, our predictive theory study will serve as a guideline for experimentalists to further explore the high-pressure polymorphism in P3N5. Our results are consistent with suggestion that new opportunities for forming novel dense non-metal nitrides exist under high-pressure and high-temperature conditions.

  9. Hydrous silicate melt at high pressure.

    PubMed

    Mookherjee, Mainak; Stixrude, Lars; Karki, Bijaya

    2008-04-24

    The structure and physical properties of hydrous silicate melts and the solubility of water in melts over most of the pressure regime of Earth's mantle (up to 136 GPa) remain unknown. At low pressure (up to a few gigapascals) the solubility of water increases rapidly with increasing pressure, and water has a large influence on the solidus temperature, density, viscosity and electrical conductivity. Here we report the results of first-principles molecular dynamics simulations of hydrous MgSiO3 melt. These show that pressure has a profound influence on speciation of the water component, which changes from being dominated by hydroxyls and water molecules at low pressure to extended structures at high pressure. We link this change in structure to our finding that the water-silicate system becomes increasingly ideal at high pressure: we find complete miscibility of water and silicate melt throughout almost the entire mantle pressure regime. On the basis of our results, we argue that a buoyantly stable melt at the base of the upper mantle would contain approximately 3 wt% water and have an electrical conductivity of 18 S m(-1), and should therefore be detectable by means of electromagnetic sounding. PMID:18432243

  10. Highly-Ordered Pyrolytic Graphite under High Pressure

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Panzik, J. E.; Kiefer, B.; Montgomery, J. M.; Lee, K. K.

    2009-12-01

    As one of the longest-known forms of carbon, graphite has been extensively studied for several decades. However, its phase diagram under high pressures is still poorly understood. Here we use both in-situ high-pressure Raman spectroscopy and synchrotron x-ray diffraction, collected on both compression and decompression, to elucidate the high-pressure behavior of highly-ordered pyrolitic graphite (HOPG) at room temperature. The Raman spectra show that G band (1580 cm-1 at ambient pressure) of HOPG shifts to higher frequency with increased pressure, which has been attributed to pressure-induced in-plane lattice contraction. Above 15 GPa the broadening of this Raman peak indicates a reordering of the atomic structure, and is consistent with synchrotron x-ray diffraction measurements that also show a slight change in symmetry.

  11. Food preservation by high pressure

    Microsoft Academic Search

    Volker Heinz; Roman Buckow

    2010-01-01

    \\u000a Abstract  Novel non-thermal food processing technologies aim to provide safe, high quality foods with desirable nutritional, physico-chemical\\u000a and sensorical properties. More recently with the use of minimal processing treatment concepts have been added to the already\\u000a existing food processing requirements. Some of them might be beneficial for the improvement of hygiene and the extension of\\u000a shelf life. This presentation will focus

  12. Sample injector for high pressure liquid chromatography

    DOEpatents

    Paul, Phillip H. (Livermore, CA); Arnold, Don W. (Livermore, CA); Neyer, David W. (Castro Valley, CA)

    2001-01-01

    Apparatus and method for driving a sample, having a well-defined volume, under pressure into a chromatography column. A conventional high pressure sampling valve is replaced by a sample injector composed of a pair of injector components connected in series to a common junction. The injector components are containers of porous dielectric material constructed so as to provide for electroosmotic flow of a sample into the junction. At an appropriate time, a pressure pulse from a high pressure source, that can be an electrokinetic pump, connected to the common junction, drives a portion of the sample, whose size is determined by the dead volume of the common junction, into the chromatographic column for subsequent separation and analysis. The apparatus can be fabricated on a substrate for microanalytical applications.

  13. Densities of liquid silicates at high pressures.

    PubMed

    Rigden, S M; Ahrens, T J; Stolper, E M

    1984-11-30

    Densities of molten silicates at high pressures (up to approximately 230 kilobars) have been measured for the first time with shock-wave techniques. For a model basaltic composition (36 mole percent anorthite and 64 mole percent diopside), a bulk modulus K(s), of approximately 230 kilobars and a pressure derivative (dK(s)/dP) of approximately 4 were derived. Some implications of these results are as follows: (i) basic to ultrabasic melts become denser than olivine-and pyroxene-rich host mantle at pressures of 60 to 100 kilobars; (ii) there is a maximum depth from which basaltic melt can rise within terrestrial planetary interiors; (iii) the slopes of silicate solidi [(dT(m)/dP), where T(m) is the temperature] may become less steep at high pressures; and (iv) enriched mantle reservoirs may have developed by downward segregation of melt early in Earth history. PMID:17839996

  14. Polymerization of Formic Acid under High Pressure

    NASA Astrophysics Data System (ADS)

    Goncharov, Alexander F.; Manaa, M. Riad; Zaug, Joseph M.; Gee, Richard H.; Fried, Laurence E.; Montgomery, Wren B.

    2005-02-01

    We report Raman, infrared, and x-ray diffraction (XRD) measurements, along with ab initio calculations on formic acid (FA) under pressure up to 50 GPa. We find an infinite chain Pna21 structure to be a high-pressure phase at room temperature. Our data indicate the symmetrization and a partially covalent character of the intrachain hydrogen bonds above approximately 20 GPa. Raman spectra and XRD patterns indicate a loss of long-range order at pressures above 40 GPa, with a large hysteresis upon decompression. We attribute this behavior to a three-dimensional polymerization of FA.

  15. A high-temperature wideband pressure transducer

    NASA Technical Reports Server (NTRS)

    Zuckerwar, A. J.

    1975-01-01

    Progress in the development of a pressure transducer for measurement of the pressure fluctuations in the high temperature environment of a jet exhaust is reported. A condenser microphone carrier system was adapted to meet the specifications. A theoretical analysis is presented which describes the operation of the condenser microphone in terms of geometry, materials, and other physical properties. The analysis was used as the basis for design of a prototype high temperature microphone. The feasibility of connecting the microphone to a converter over a high temperature cable operating as a half-wavelength transmission line was also examined.

  16. ALTERNATIVES FOR HIGH-TEMPERATURE/HIGH-PRESSURE PARTICULATE CONTROL

    EPA Science Inventory

    The report gives the status of the most promising high-temperature/high-pressure (HTP) particulate control devices being developed. Data are presented and anticipated performance and development problems are discussed. HTP particulate control offers efficiency and potential econo...

  17. Single Molecule Raman Spectroscopy Under High Pressure

    NASA Astrophysics Data System (ADS)

    Fu, Yuanxi; Dlott, Dana

    2014-06-01

    Pressure effects on surface-enhanced Raman scattering spectra of Rhdoamine 6G adsorbed on silver nanoparticle surfaces was studied using a confocal Raman microscope. Colloidal silver nanoparticles were treated with Rhodamine 6G (R6G) and its isotopically substituted partner, R6G-d4. Mixed isotopomers let us identify single-molecule spectra, since multiple-molecule spectra would show vibrational transitions from both species. The nanoparticles were embedded into a poly vinyl alcohol film, and loaded into a diamond anvil cell for the high-pressure Raman scattering measurement. Argon was the pressure medium. Ambient pressure Raman scattering spectra showed few single-molecule spectra. At moderately high pressure ( 1GPa), a surprising effect was observed. The number of sites with observable spectra decreased dramatically, and most of the spectra that could be observed were due to single molecules. The effects of high pressure suppressed the multiple-molecule Raman sites, leaving only the single-molecule sites to be observed.

  18. High Pressure Electrochemistry: Application to silver halides

    NASA Astrophysics Data System (ADS)

    Havens, K.; Kavner, A.

    2007-12-01

    Electron and ion charge transfer processes help govern electrical conductivity and diffusive mass and heat transport properties in deep Earth minerals. In an attempt to understand how pressure influences charge transfer behavior, the halide silver bromide (AgBr) was studied under the influence of an electric potential difference applied across two electrodes in a diamond anvil cell. This study follows our previous work on AgI, which was found to dissociate to molecular iodine and silver metal due to pressure and voltage influences. We performed two sets of experiments on AgBr at high pressure in a diamond anvil cell: electrochemical dissociation and electrical resistance measurements. In our study, we were able to electrochemically dissociate AgBr at pressures of 0.25-1.6 GPa by applying a voltage across the electrodes in the diamond cell sample chamber. Ag metal grew visibly on the negatively-charged electrode when voltages varying from 0.1 V to 5 V were applied. Additionally, a dark blue color appeared in low pressure areas of the diamond cell and grew darker from both voltage application and light exposure, indicating photochemical effects. We found that the reaction area and growth rate of both metal and dark blue color strongly increased as voltage increased, but tended to decrease with greater pressure. The resistance across the cell was observed to be influenced by both pressure and light exposure. As the AgBr sample was exposed to visible light, the resistance dropped instantaneously, and after the light was turned off, the resistance increased on a timescale of 10's of seconds to minutes. Notably, at higher pressures, the AgBr showed less photosensitivity. Exploration of these metal halide systems has many potential applications. First, these experiments explore the pressure-dependence of photochemical and photovoltaic processes, and may spur development of pressure-tuned microscale electronic devices. Second, these experimental results can be used to constrain thermodynamic models of pressure-dependent electrochemical behavior of materials, which may then be applied to the high temperature, high pressure mineral phases of the deep Earth and planets.

  19. Dynamics of Low-Pressure and High-Pressure Fuel Cell Air Supply System1

    E-print Network

    Peng, Huei

    48109 Abstract Choosing an operating pressure is a critical decision that de- fines many characteristics at the dy- namic characteristics of both high-pressure and low-pressure systems. The model of a low comparing the low pressure system with the high- pressure system equipped with a high-speed compressor

  20. High pressure, high current, low inductance, high reliability sealed terminals

    DOEpatents

    Hsu, John S. (Oak Ridge, TN) [Oak Ridge, TN; McKeever, John W. (Oak Ridge, TN) [Oak Ridge, TN

    2010-03-23

    The invention is a terminal assembly having a casing with at least one delivery tapered-cone conductor and at least one return tapered-cone conductor routed there-through. The delivery and return tapered-cone conductors are electrically isolated from each other and positioned in the annuluses of ordered concentric cones at an off-normal angle. The tapered cone conductor service can be AC phase conductors and DC link conductors. The center core has at least one service conduit of gate signal leads, diagnostic signal wires, and refrigerant tubing routed there-through. A seal material is in direct contact with the casing inner surface, the tapered-cone conductors, and the service conduits thereby hermetically filling the interstitial space in the casing interior core and center core. The assembly provides simultaneous high-current, high-pressure, low-inductance, and high-reliability service.

  1. Fluid hydrogen at high density - Pressure dissociation

    NASA Technical Reports Server (NTRS)

    Saumon, Didier; Chabrier, Gilles

    1991-01-01

    A model for the Helmholtz free energy of fluid hydrogen at high density and high temperature is developed. This model aims at describing both pressure and temperature dissociation and ionization and bears directly on equations of state of partially ionized plasmas, as encountered in astrophysical situations and high-pressure experiments. This paper focuses on a mixture of hydrogen atoms and molecules and is devoted to the study of the phenomenon of pressure dissociation at finite temperatures. In the present model, the strong interactions are described with realistic potentials and are computed with a modified Weeks-Chandler-Andersen fluid perturbation theory that reproduces Monte Carlo simulations to better than 3 percent. Theoretical Hugoniot curves derived from the model are in excellent agreement with experimental data.

  2. High pressure chemistry of substituted acetylenes

    SciTech Connect

    Chellappa, Raja [Los Alamos National Laboratory; Dattelbaum, Dana [Los Alamos National Laboratory; Sheffield, Stephen [Los Alamos National Laboratory; Robbins, David [Los Alamos National Laboratory

    2011-01-25

    High pressure in situ synchrotron x-ray diffraction experiments were performed on substituted polyacetylenes: tert-butyl acetylene [TBA: (CH{sub 3}){sub 3}-C{triple_bond}CH] and ethynyl trimethylsilane [ETMS: (CH{sub 3}){sub 3}-Si{triple_bond}CH] to investigate pressure-induced chemical reactions. The starting samples were the low temperature crystalline phases which persisted metastably at room temperature and polymerized beyond 11 GPa and 26 GPa for TBA and ETMS respectively. These reaction onset pressures are considerably higher than what we observed in the shockwave studies (6.1 GPa for TBA and 6.6 GPa for ETMS). Interestingly, in the case of ETMS, it was observed with fluid ETMS as starting sample, reacts to form a semi-crystalline polymer (crystalline domains corresponding to the low-T phase) at pressures less than {approx}2 GPa. Further characterization using vibrational spectroscopy is in progress.

  3. High pressure water jet cutting and stripping

    NASA Technical Reports Server (NTRS)

    Hoppe, David T.; Babai, Majid K.

    1991-01-01

    High pressure water cutting techniques have a wide range of applications to the American space effort. Hydroblasting techniques are commonly used during the refurbishment of the reusable solid rocket motors. The process can be controlled to strip a thermal protective ablator without incurring any damage to the painted surface underneath by using a variation of possible parameters. Hydroblasting is a technique which is easily automated. Automation removes personnel from the hostile environment of the high pressure water. Computer controlled robots can perform the same task in a fraction of the time that would be required by manual operation.

  4. A novel high pressure tool: the solvation pressure of liquids

    NASA Astrophysics Data System (ADS)

    Hubel, H.; van Uden, N. W. A.; Faux, D. A.; Dunstan, D. J.

    2004-04-01

    Co-solvents were studied to determine if the change in the cohesive energy density (CED) generates an effective solvation pressure equivalent to the application of an external hydrostatic pressure. Raman modes of chloroform under hydrostatic pressure with co-solvents (chloroform-ethanol, chloroform-acetone) and in the vapour phase were recorded. In some cases the Raman frequency shifts indicate that the solvation pressure behaves as a true hydrostatic pressure. The pressure-induced gelation of starch grains was studied in aqueous media. A higher co-solvent concentration is postulated to put the grains under effective negative pressure, and indeed an increase in the external pressure needed for gelation was seen after the introduction of solvents. The quantitative agreement between the change of solvation pressure and hydrostatic pressure is very good over a wide range of solvent concentration.

  5. Know Your Blood Pressure Many people with diabetes also have high blood pressure.

    E-print Network

    Know Your Blood Pressure Many people with diabetes also have high blood pressure. Blood pressure whole body. #12; When your heart pumps, your blood pressure goes up. The pressure in your arteries is your blood pressure. · This is like pumping air into a tire. · When you push down on the pump it pumps

  6. Introduction to High-Pressure Science

    NASA Astrophysics Data System (ADS)

    Dera, Przemyslaw

    To a common person pressure is just one of the parameters that describe a thermodynamic state. We all hear about it in everyday weather forecasts, and most of us do not associate it with anything particularly unique. Probably the most intuitive idea of the effect of high-pressure comes from movies, where submarine sinking to the bottom of the ocean is gradually crushed by the surrounding water, until its hull implodes. Why, then hundreds of scientists throughout the world spent their lifelong careers studying high-pressure phenomena? Despite all the developments in experimental technologies and instrumentation, modern scientist has very few tools that allow him or her to "grab" two atoms and bring them, in a very controllable way, closer together. Being able to achieve this task means the ability to directly probe interatomic interaction potentials and can cause transformations as dramatic as turning of a common gas into solid metal. Before the reader delves into more advanced topics described later in this book, this introductory chapter aims to explain several elementary, but extremely important concepts in high-pressure science. We will start with a brief discussion of laboratory devices used to produce pressure, address the issue of hydrostaticity, elastic and plastic compression, and will conclude with a short discussion of unique effects of anisotropic stress.

  7. High pressure turbomachinery ground test facility

    NASA Technical Reports Server (NTRS)

    Scheuermann, Patrick E.

    1992-01-01

    Turbomachinery test facilities are at present scarce to non-existent world-wide. The turbomachinery test facility at Stennis Space Center will provide for advanced development and research and development capabilities for liquid hydrogen/liquid oxygen propellant rocket engine components. The facility will provide ultra-high pressure via gas generators to deliver the needed turbine drive on various turbomachinery. State of the art process control systems will provide the vital pressure, temperature and flow requirements during tests. These systems will better control adverse transient conditions during start-up and shutdown, and by using advanced control theory, as well as incorporate test article health monitoring. Also, digital data acquisition systems will obtain high frequency (up to 20 KHz) and low frequency (up to 1 KHz) data during the test. Pressures of up to 15,000 psi will be generated to pressurize high pressure tanks supplying cryogens to various test article inlets thus pushing turbopump materials and manufacturing processes to their limits. By planning for future projects the test facility will be easily adaptable to multi-program test configurations over a range of thermodynamic positions.

  8. 46 CFR 58.30-20 - Fluid power hose and fittings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 2010-10-01 2010-10-01 false Fluid power hose and fittings. 58.30-20 ...AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-20 Fluid power hose and fittings. (a) The...

  9. 46 CFR 58.30-20 - Fluid power hose and fittings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 2014-10-01 2014-10-01 false Fluid power hose and fittings. 58.30-20 ...AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-20 Fluid power hose and fittings. (a) The...

  10. 46 CFR 58.30-20 - Fluid power hose and fittings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 2013-10-01 2013-10-01 false Fluid power hose and fittings. 58.30-20 ...AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-20 Fluid power hose and fittings. (a) The...

  11. 46 CFR 58.30-20 - Fluid power hose and fittings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 2012-10-01 2012-10-01 false Fluid power hose and fittings. 58.30-20 ...AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-20 Fluid power hose and fittings. (a) The...

  12. 46 CFR 58.30-20 - Fluid power hose and fittings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 2011-10-01 2011-10-01 false Fluid power hose and fittings. 58.30-20 ...AND AUXILIARY MACHINERY AND RELATED SYSTEMS Fluid Power and Control Systems § 58.30-20 Fluid power hose and fittings. (a) The...

  13. Superconducting high-pressure phases of disilane

    PubMed Central

    Jin, Xilian; Meng, Xing; He, Zhi; Ma, Yanming; Liu, Bingbing; Cui, Tian; Zou, Guangtian; Mao, Ho-kwang

    2010-01-01

    High-pressure structures of disilane (Si2H6) are investigated extensively by means of first-principles density functional theory and a random structure-searching method. Three metallic structures with P-1, Pm-3m, and C2/c symmetries are found, which are more stable than those of XY3-type candidates under high pressure. Enthalpy calculations suggest a remarkably wide decomposition (Si and H2) pressure range below 135 GPa, above which three metallic structures are stable. Perturbative linear-response calculations for Pm-3m disilane at 275 GPa show a large electron-phonon coupling parameter ? of 1.397 and the resulting superconducting critical temperature beyond the order of 102 K. PMID:20479272

  14. Corrosion control in high pressure steam generators

    Microsoft Academic Search

    T. W. Ford; K. R. Walston

    1976-01-01

    A description is presented of work done and changes of operating parameters found necessary to reduce the rate of scale laydown and corrosion in high pressure boilers. There is no magic formula for success in this field. Constant monitoring of the raw water supply to ensure low colloid levels, of the demin water to ensure low organic and colloid levels,

  15. Food Processing by High Hydrostatic Pressure

    Microsoft Academic Search

    M. F. San Martín; G. V. Barbosa-Cánovas; B. G. Swanson

    2002-01-01

    The use of high hydrostatic pressures (HHP) for food processing is finding increased application within the food industry. One of the advantages of this technology is that because it does not use heat, sensory, and nutritional attributes of the product remain virtually unaffected, thus yielding products with better quality than those processed traditional methods. HHP have the ability to inactivate

  16. High-pressure treatment of polytene chromosomes

    E-print Network

    Cai, Long

    High-pressure treatment of polytene chromosomes improves structural resolution Dmitri V Novikov1 to immunofluorescence and in situ hybridization. D. melanogaster cells in many larval tissues undergo repeated rounds. Bridges' hand-drawn chromosome maps (republished in ref. 6) are still considered the definitive

  17. High pressure: Bacteria survive inside diamond anvil

    NSDL National Science Digital Library

    Editor-in-Chief Culliton J. Barbara

    This is a summary of a research paper describing experiments conducted to study bacterial survival at extremely high pressure. This web article published by the Genome News Network is a review of the original publication found in Science magazine. A link to the original publication is found at the end of the article.

  18. Sterilization using high-pressure carbon dioxide

    Microsoft Academic Search

    Jian Zhang; Thomas A. Davis; Michael A. Matthews; Michael J. Drews; Martine LaBerge; Yuehuei H. An

    2006-01-01

    Sterility is required for medical devices use in invasive medical procedures, and for some situations in the food industry. Sterilization of heat-sensitive or porous materials or devices, such as endoscopes, porous implants, liquid foodstuff, and liquid medicine, poses a challenge to current technologies. There has been a steady interest in using high-pressure carbon dioxide as a process medium for new

  19. (Ultra) High Pressure Homogenization for Continuous High Pressure Sterilization of Pumpable Foods – A Review

    PubMed Central

    Georget, Erika; Miller, Brittany; Callanan, Michael; Heinz, Volker; Mathys, Alexander

    2014-01-01

    Bacterial spores have a strong resistance to both chemical and physical hurdles and create a risk for the food industry, which has been tackled by applying high thermal intensity treatments to sterilize food. These strong thermal treatments lead to a reduction of the organoleptic and nutritional properties of food and alternatives are actively searched for. Innovative hurdles offer an alternative to inactivate bacterial spores. In particular, recent technological developments have enabled a new generation of high pressure homogenizer working at pressures up to 400?MPa and thus, opening new opportunities for high pressure sterilization of foods. In this short review, we summarize the work conducted on (ultra) high pressure homogenization (U)HPH to inactivate endospores in model and food systems. Specific attention is given to process parameters (pressure, inlet, and valve temperatures). This review gathers the current state of the art and underlines the potential of UHPH sterilization of pumpable foods while highlighting the needs for future work. PMID:25988118

  20. High pressure microscopy--a powerful tool for monitoring cells and macromolecules under high hydrostatic pressure.

    PubMed

    Hartmann, M; Kreuss, M; Sommer, K

    2004-06-01

    A high pressure chamber, which withstands a pressure up to 300 MPa has been developed. The so-called HPDS (Hartmann, Pfeifer, Dornheim, Sommer) High Pressure Cell in combination with an inverted microscope and an analysis system allows brilliant microscopic colour pictures with an optical resolution better than 0.56 microm. The pressure chamber allows the in situ observation of dynamic changes of microscopic structures in bright field, phase contrast and fluorescence microscopy. This publication should demonstrate the capabilities of the system using results of experiments with two types of Spirogyra algae. The pictures have shown significant variations of the chloroplasma and the cell wall membrane at pressures of up to 120 MPa. The new system provides a simple way to perform microscopic analyses at pressures of up to 300 MPa. PMID:15529757

  1. A high temperature high pressure cell for quasielastic neutron scattering.

    PubMed

    Yang, F; Kaplonski, J; Unruh, T; Mamontov, E; Meyer, A

    2011-08-01

    We present our recent development of a high temperature high pressure cell for neutron scattering. Combining a water cooled Nb1Zr pressure cell body with an internal heating furnace, the sample environment can reach temperatures of up to 1500 K at a pressure of up to 200 MPa at the sample position, with an available sample volume of about 700 mm(3). The cell material Nb1Zr is specifically chosen due to its reasonable mechanical strength at elevated temperatures and fairly small neutron absorption and incoherent scattering cross sections. With this design, an acceptable signal-to-noise ratio of about 10:1 can be achieved. This opens new possibilities for quasielastic neutron scattering studies on different types of neutron spectrometers under high temperature high pressure conditions, which is particularly interesting for geological research on, e.g., water dynamics in silicate melts. PMID:21895254

  2. High pressure luminescence probes in polymers

    SciTech Connect

    Drickamer, H.G.

    1980-01-01

    High pressure luminescence has proved to be a very powerful tool for characterizing crystalline solids and liquids. Two problems involving glassy polymers are analyzed. In the first problem the excited states of azulene and its derivatives are used to probe intermolecular interactions in PMMA and PS. In the second problem the change in emission intensity with pressure from two excimer states of polyvinylcarbazole as a pure polymer and in dilute solution in polystyrene (PS), polymethylmethacrylate (PMMA) and polyisoliutylene (PIB) is studied. The relative emission from the two states depends strongly on the possibility for motion of polymer segments. The observations are related to the proximity to the glass transition.

  3. Doped high- Tc superconductors under pressure

    NASA Astrophysics Data System (ADS)

    Orozco, S.; Ortiz, M. A.; Méndez-Moreno, R. M.; Moreno, M.

    2008-12-01

    Within the BCS framework generalized Fermi surface topologies, modeled with band overlapping, are proposed as a mechanism to enhance the electronic density of states at the Fermi level. This band overlapping allows the high- Tc values observed in cuprate superconductors at different pressures. With this approach the correlation between the critical temperature, the charge carrier density and the pressure is obtained in terms of the coupling constant and the band overlapping parameter. In order to obtain numerical results the model is applied to a Tl-based superconductor.

  4. Evaluation of a Pump and Reeled Hose System for Studying the Vertical

    E-print Network

    545 Evaluation of a Pump and Reeled Hose System for Studying the Vertical Distribution of Small Evaluation of a Pump and Reeled Hose System for Studying the Vertical Distribution of Small Plankton Advantages and limitations of a pump and reeled hose system 8 Literature cited 9 #12;#12;Evaluation of a Pump

  5. 46 CFR 34.10-10 - Fire station hydrants, hose and nozzles-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...station hydrants, hose and nozzles-T/ALL. 34.10-10 Section 34.10-10...station hydrants, hose and nozzles—T/ALL. (a) The size of fire station hydrants...length of hose. In main machinery spaces all portions of such spaces shall be...

  6. 46 CFR 35.40-15 - Fire hose stations-TB/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Fire hose stations-TB/ALL. 35.40-15 Section 35.40-15 Shipping...OPERATIONS Posting and Marking Requirements-TB/ALL § 35.40-15 Fire hose stations—TB/ALL. At each fire hose valve there shall be...

  7. 46 CFR 35.40-15 - Fire hose stations-TB/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Fire hose stations-TB/ALL. 35.40-15 Section 35.40-15 Shipping...OPERATIONS Posting and Marking Requirements-TB/ALL § 35.40-15 Fire hose stations—TB/ALL. At each fire hose valve there shall be...

  8. 46 CFR 35.40-15 - Fire hose stations-TB/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Fire hose stations-TB/ALL. 35.40-15 Section 35.40-15 Shipping...OPERATIONS Posting and Marking Requirements-TB/ALL. § 35.40-15 Fire hose stations—TB/ALL. At each fire hose valve there shall be...

  9. 46 CFR 34.10-10 - Fire station hydrants, hose and nozzles-T/ALL.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...station hydrants, hose and nozzles-T/ALL. 34.10-10 Section 34.10-10...station hydrants, hose and nozzles—T/ALL. (a) The size of fire station hydrants...length of hose. In main machinery spaces all portions of such spaces shall be...

  10. 46 CFR 34.10-10 - Fire station hydrants, hose and nozzles-T/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...station hydrants, hose and nozzles-T/ALL. 34.10-10 Section 34.10-10...station hydrants, hose and nozzles—T/ALL. (a) The size of fire station hydrants...length of hose. In main machinery spaces all portions of such spaces shall be...

  11. 46 CFR 35.40-15 - Fire hose stations-TB/ALL.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Fire hose stations-TB/ALL. 35.40-15 Section 35.40-15 Shipping...OPERATIONS Posting and Marking Requirements-TB/ALL. § 35.40-15 Fire hose stations—TB/ALL. At each fire hose valve there shall be...

  12. 46 CFR 34.10-10 - Fire station hydrants, hose and nozzles-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...station hydrants, hose and nozzles-T/ALL. 34.10-10 Section 34.10-10...station hydrants, hose and nozzles—T/ALL. (a) The size of fire station hydrants...length of hose. In main machinery spaces all portions of such spaces shall be...

  13. 46 CFR 35.40-15 - Fire hose stations-TB/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Fire hose stations-TB/ALL. 35.40-15 Section 35.40-15 Shipping...OPERATIONS Posting and Marking Requirements-TB/ALL § 35.40-15 Fire hose stations—TB/ALL. At each fire hose valve there shall be...

  14. High pressure fiber optic light scattering spectrometer

    NASA Astrophysics Data System (ADS)

    Zhou, Shuiqin; Chu, Benjamin; Dhadwal, H. S.

    1998-05-01

    A high-pressure fiber-optic light-scattering spectrometer has been constructed for in situ observation of molecular dissolution/association as well as the polymerization process in supercritical fluids. Single (or multiple) fiber-optic probes, each comprised of a single optical fiber (or multiple optical fibers) and a graded index microlens, are used to transmit the incident laser beam and to receive the scattered light as well as the transmitted light from the high pressure cell. The direct immersion in the scattering medium of the fiber-optic probes makes the spectrometer more compact and more flexible with an easier alignment process. With the miniaturization and flexibility, our high-pressure light-scattering cell can be transported and adapted in combination with other physical techniques, such as synchrotron small angle x-ray scattering which requires a different set of windows (e.g., made of diamond) suitable for x-ray transmissions. This spectrometer has been successfully used for the in situ study of the molecular association behavior of a diblock copolymer of 1,1-dihydroperfluorooctylacrylate and vinyl acetate in supercritical carbon dioxide under pressures up to 552 bar.

  15. Apparatus for testing high pressure injector elements

    NASA Technical Reports Server (NTRS)

    Myers, William Neill (inventor); Scott, Ewell M. (inventor); Forbes, John C. (inventor); Shadoan, Michael D. (inventor)

    1995-01-01

    An apparatus for testing and evaluating the spray pattern of high pressure fuel injector elements for use in supplying fuel to combustion engines is presented. Prior art fuel injector elements were normally tested by use of low pressure apparatuses which did not provide a purge to prevent mist from obscuring the injector element or to prevent frosting of the view windows; could utilize only one fluid during each test; and had their viewing ports positioned one hundred eighty (180 deg) apart, thus preventing optimum use of laser diagnostics. The high pressure fluid injector test apparatus includes an upper hub, an upper weldment or housing, a first clamp and stud/nut assembly for securing the upper hub to the upper weldment, a standoff assembly within the upper weldment, a pair of window housings having view glasses within the upper weldment, an injector block assembly and purge plate within the upper weldment for holding an injector element to be tested and evaluated, a lower weldment or housing, a second clamp and stud/nut assembly for securing the lower weldment to the upper hub, a third clamp and stud/nut assembly for securing the lower hub to the lower weldment, mechanisms for introducing fluid under high pressure for testing an injector element, and mechanisms for purging the apparatus to prevent frosting of view glasses within the window housings and to permit unobstructed viewing of the injector element.

  16. Small, high-pressure, liquid oxygen turbopump

    NASA Technical Reports Server (NTRS)

    Csomor, A.

    1978-01-01

    A small, high-pressure, LOX turbopump was designed, fabricated, and tested. The pump was of a single-stage, centrifugal type; power to the pump was supplied by a single-stage, partial-admission, axial-impulse turbine. Design conditions included an operating speed of 7330 rad/sec (70,000 rpm) pump discharge pressure of 2977 N/sq cm (4318 psia), and a pump flowrate of 16.4 kg/s (36.21 lb/sec). The turbine was propelled by LOX/LH2 combustion products at 1041 K (1874 R) inlet temperature, and at a design pressure ratio of 1.424. Test data obtained with the turbopump are presented and mechanical performance is discussed.

  17. 7 CFR 58.219 - High pressure pumps and lines.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 2012-01-01 false High pressure pumps and lines. 58.219 Section 58.219...and Utensils § 58.219 High pressure pumps and lines. High pressure lines may...dead ends, valves and the high pressure pumps can be disassembled for hand...

  18. 7 CFR 58.219 - High pressure pumps and lines.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 2013-01-01 false High pressure pumps and lines. 58.219 Section 58.219...and Utensils § 58.219 High pressure pumps and lines. High pressure lines may...dead ends, valves and the high pressure pumps can be disassembled for hand...

  19. 7 CFR 58.219 - High pressure pumps and lines.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2011-01-01 false High pressure pumps and lines. 58.219 Section 58.219...and Utensils § 58.219 High pressure pumps and lines. High pressure lines may...dead ends, valves and the high pressure pumps can be disassembled for hand...

  20. 7 CFR 58.219 - High pressure pumps and lines.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2014-01-01 false High pressure pumps and lines. 58.219 Section 58.219...and Utensils § 58.219 High pressure pumps and lines. High pressure lines may...dead ends, valves and the high pressure pumps can be disassembled for hand...

  1. 7 CFR 58.219 - High pressure pumps and lines.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 2010-01-01 false High pressure pumps and lines. 58.219 Section 58.219...and Utensils § 58.219 High pressure pumps and lines. High pressure lines may...dead ends, valves and the high pressure pumps can be disassembled for hand...

  2. Engine having a high pressure hydraulic system and low pressure lubricating system

    DOEpatents

    Bartley, Bradley E. (Manito, IL); Blass, James R. (Bloomington, IL); Gibson, Dennis H. (Chillicothe, IL)

    2000-01-01

    An engine includes a high pressure hydraulic system having a high pressure pump and at least one hydraulically-actuated device attached to an engine housing. A low pressure engine lubricating system is attached to the engine housing and includes a circulation conduit fluidly connected to an outlet from the high pressure pump.

  3. High-pressure apparatus for dielectric measurements in high frequency.

    PubMed

    Ai, B; Lebarbier, D; The Giam, H; Bapt, J C; Farzaneh, M

    1979-05-01

    The present article describes an experimental apparatus for the measurement of low-loss dielectric material under conditions of high pressures (maximum pressure 1500 bars) and high frequencies (1-15 MHz.) The measurements of these losses are based on the classical method of the Q-meter with a general Radio type 1690-A sample holder, located in a high-pressure bomb. All the manual operations made on the holder during the measurements are controlled by dc motors. The first results have shown that the dielectric losses of polyethylene (PE) vary with the pressure. This apparatus will later be used in the measurement of the dielectric losses of the insulating materials used for submarine telecommunication cables. PMID:18699565

  4. 46 CFR 181.320 - Fire hoses and nozzles.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...paragraphs (b)(1) and (b)(3) of this section or be garden type hose of not less than 16 millimeters (0.625 inches...15.25 meters (50 feet) in length; and (3) If of the garden type, be of a good commercial grade constructed of an...

  5. 46 CFR 181.320 - Fire hoses and nozzles.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...paragraphs (b)(1) and (b)(3) of this section or be garden type hose of not less than 16 millimeters (0.625 inches...15.25 meters (50 feet) in length; and (3) If of the garden type, be of a good commercial grade constructed of an...

  6. High-pressure droplet combustion studies

    NASA Technical Reports Server (NTRS)

    Mikami, Masato; Kono, M.; Sato, Junichi; Dietrich, Daniel L.; Williams, Forman A.

    1993-01-01

    This is a joint research program, pursued by investigators at the University of Tokyo, UCSD, and NASA Lewis Research Center. The focus is on high-pressure combustion of miscible binary fuel droplets. It involves construction of an experimental apparatus in Tokyo, mating of the apparatus to a NASA-Lewis 2.2-second drop-tower frame in San Diego, and performing experiments in the 2.2-second tower in Cleveland, with experimental results analyzed jointly by the Tokyo, UCSD, and NASA investigators. The project was initiated in December, 1990 and has now involved three periods of drop-tower testing by Mikami at Lewis. The research accomplished thus far concerns the combustion of individual fiber-supported droplets of mixtures of n-heptane and n-hexadecane, initially about 1 mm diameter, under free-fall microgravity conditions. Ambient pressures ranged up to 3.0 MPa, extending above the critical pressures of both pure fuels, in room-temperature nitrogen-oxygen atmospheres having oxygen mole fractions X of 0.12 and 0.13. The general objective is to study near-critical and super-critical combustion of these droplets and to see whether three-stage burning, observed at normal gravity, persists at high pressures in microgravity. Results of these investigations will be summarized here; a more complete account soon will be published.

  7. Picosecond High Pressure Gas Switch experiment

    SciTech Connect

    Cravey, W.R.; Freytag, E.K.; Goerz, D.A.; Poulsen, P.; Pincosy, P.A.

    1993-08-01

    A high Pressure Gas Switch has been developed and tested at LLNL. Risetimes on the order of 200 picoseconds have been observed at 1 kHz prf and 1 atmosphere pressures. Calculations show that switching closure times on the order of tens of picoseconds can be achieved at higher pressures and electric fields. A voltage hold-off of 1 MV/cm has been measured at 10 atmospheres and several MV/cm appears possible with the HPGS. With such high electric field levels, energy storage of tens of Joules in a reasonably sized package is achievable. Initial HPGS performance has been characterized using the WASP pulse generator at LLNL. A detailed description of the switch used for initial testing is given. Switch recovery times of 1-ms have been measured at 1 atmosphere. Data on the switching uniformity, voltage hold-off recovery, and pulse repeatability, is presented. In addition, a physics switch model is described and results are compared with experimental data. Modifications made to the WASP HV pulser in order to drive the HPGS will also be discussed. Recovery times of less than 1 ms were recorded without gas flow in the switch chambers. Low pressure synthetic air was used as the switch dielectric. Longer recovery times were required when it was necessary to over-voltage the switch.

  8. Diffusion creep of enstatite at high pressures

    NASA Astrophysics Data System (ADS)

    Zhang, G.; Mei, S.; Kohlstedt, D. L.

    2014-12-01

    Deformation behavior of fine-grained enstatite (g.s. ~ 8 ?m) was investigated with triaxial compressive creep experiments at high pressures (4.2 - 6.9 GPa) and high temperatures (1373 - 1573 K) using a deformation-DIA apparatus. Experiments were carried out under anhydrous conditions. In each experiment, a sample column composed of a sample and alumina pistons was assembled with a boron nitride sleeve and graphite resistance heater into a 6.2-mm edge length cubic pressure medium. Experiments were carried out at the National Synchrotron Light Source at Brookhaven National Laboratory. In a run, differential stress and sample displacement were monitored in-situ using synchrotron x-ray diffraction and radiography, respectively. Based on results from this study, the deformation behavior of enstatite under anhydrous conditions has been quantitatively presented in the form of a flow law that describes the dependence of deformation rate on stress, temperature, and pressure. Specifically, data fitting yields the dependence of creep rate on stress with an exponent of n ? 1; indicating samples were deformed in the regime of diffusion creep. Experimental results also yield the dependences of creep rate on temperature and pressure with an activation energy of ~250 kJ/mol and activation volume of ~3.5×10-6 m3/mol, respectively. The flow laws for enstatite, one important constituent component for the upper mantle, quantified from this study provides a necessary constraint for modeling the dynamic activities occurring within Earth's interior.

  9. High Pressure Effect on Meat and Lupin Protein Digestibility

    Microsoft Academic Search

    M. de Lamballerie-Anton; S. Delépine; N. Chapleau

    2002-01-01

    High pressure treatment is a mild treatment concerning the nutritional characteristics: for instance vitamins content is very few affected by high-pressure treatment. But the impact of high-pressure on protein digestibility remains poorly understood. This work presents effect of high-pressure treatment on in vitro digestibility of meat and lupin proteins. Two high-pressure conditions (200 and 500 MPa 10 min.) and a

  10. Filament wound pressure vessels - Effects of using liner tooling of low pressure vessels for high pressure vessels development

    NASA Astrophysics Data System (ADS)

    Lal, Krishna M.

    High performance pressure vessels have been recently demanded for aerospace and defense applications. Filament wound pressure vessels consist of a metallic thin liner, which also acts as a mandrel, and composite/epoxy overwrap. Graphite/epoxy overwrapped vessels have been developed to obtain the performance ratio, PV/W, as high as one million inches. Under very high pressure the isotropic metallic liner deforms elasto-plastically, and orthotropic composite fibers deform elastically. Sometimes, for the development of ultra high pressure vessels, composite pressure vessels industry uses the existing liner tooling developed for low burst pressure capacity composite vessels. This work presents the effects of various design variables including the low pressure liner tooling for the development of the high burst pressure capacity Brilliant Pebbles helium tanks. Advance stress analysis and development of an ultra high pressure helium tank.

  11. Bacterial inactivation by high-pressure homogenisation and high hydrostatic pressure

    Microsoft Academic Search

    Elke Y Wuytack; Ann M. J Diels; Chris W Michiels

    2002-01-01

    The resistance of five gram-positive bacteria, Enterococcus faecalis, Staphylococcus aureus, Lactobacillus plantarum, Listeria innocua and Leuconostoc dextranicum, and six gram-negative bacteria, Salmonella enterica serovar typhimurium, Shigella flexneri, Yersinia enterocolitica, Pseudomonas fluorescens and two strains of Escherichia coli, to high-pressure homogenisation (100–300 MPa) and to high hydrostatic pressure (200–400 MPa) was compared in this study. Within the group of gram-positive bacteria

  12. High pressure hydrogen time projection chamber

    SciTech Connect

    Goulianos, K.

    1983-01-01

    We describe a high pressure hydrogen gas time projection chamber which consists of two cylindrical drift regions each 45 cm in diameter and 75 cm long. Typically, at 15 atm of H/sub 2/ with 2 kV/cm drift field and 7 kV on the 35..mu.. sense wires, the drift velocity is about 0.5 cm/..mu..sec and the spatial resolution +-200..mu...

  13. Small, high pressure liquid hydrogen turbopump

    NASA Technical Reports Server (NTRS)

    Csomor, A.; Warren, D. J.

    1980-01-01

    A high pressure, low capacity, liquid hydrogen turbopump was designed, fabricated, and tested. The design configuration of the turbopump is summarized and the results of the analytical and test efforts are presented. Approaches used to pin point the cause of poor suction performance with the original design are described and performance data are included with an axial inlet design which results in excellent suction capability.

  14. MEASUREMENT OF HIGH-TEMPERATURE, HIGH-PRESSURE PROCESSES

    EPA Science Inventory

    The report reviews the first year's efforts under a planned 3-year program to develop measurement techniques for high-temperature, high-pressure (HTP) processes. Several related topics are discussed in detail, including: (1) the design, development, and successful demonstration o...

  15. High-Pressure Crystallography of Biomolecules: Recent Achievements. II - Applications

    NASA Astrophysics Data System (ADS)

    Fourme, Roger; Ascone, Isabella; Kahn, Richard; Girard, Eric

    This chapter gives various applications around the general theme of macromolecular crystallography (MX) and high pressure (HP). We first describe high-pressure cooling where crystallographic data collection is performed at ambient pressure. Then we give selected examples with data collection at high pressure (HPMX); they include compressibility measurements and structural studies on polynucleotides, an oligomeric protein and a virus capsid. Finally, we show that high pressure and methods developed for HPMX have impacts on conventional MX.

  16. High-Pressure Trocar Insertion Technique

    PubMed Central

    Reich, Harry; Conti Ribeiro, Sergio; Rasmussen, Carsten; Rosenberg, Jay

    1999-01-01

    Background: The majority of laparoscopic complications occur at the time of Veress needle and trocar insertion. Although not very frequent, they increase the morbidity and mortality of both diagnostic and operative laparoscopic procedures. Alternative techniques of trocar insertion have been described but have not completely eliminated the risk of injury. Technique: After Veress needle insertion and establishment of pneumoperitoneum to 25 to 30 mm Hg, insertion of a short trocar is performed in the deepest part of the umbilicus without elevation of the anterior abdominal wall. The result is a parietal peritoneal puncture directly beneath the umbilicus. The high-pressure setting used during initial insertion of the trocar is lowered as soon as safe abdominal entry is documented. Experience: The trocar insertion technique described above was performed in 3041 procedures. No vascular injury occurred. There were two bowel perforations. No complications related to the increased intra-abdominal pressure were observed. Conclusion: The high-pressure abdominal entry technique has the advantage of reducing intra-abdominal trocar-related injuries without requiring additional instrumentation or additional training. PMID:10323169

  17. High temperature and pressure electrochemical test station

    NASA Astrophysics Data System (ADS)

    Chatzichristodoulou, C.; Allebrod, F.; Mogensen, M.

    2013-05-01

    An electrochemical test station capable of operating at pressures up to 100 bars and temperatures up to 400 °C has been established. It enables control of the partial pressures and mass flow of O2, N2, H2, CO2, and H2O in a single or dual environment arrangement, measurements with highly corrosive media, as well as localized sampling of gas evolved at the electrodes for gas analysis. A number of safety and engineering design challenges have been addressed. Furthermore, we present a series of electrochemical cell holders that have been constructed in order to accommodate different types of cells and facilitate different types of electrochemical measurements. Selected examples of materials and electrochemical cells examined in the test station are provided, ranging from the evaluation of the ionic conductivity of liquid electrolytic solutions immobilized in mesoporous ceramic structures, to the electrochemical characterization of high temperature and pressure alkaline electrolysis cells and the use of pseudo-reference electrodes for the separation of each electrode contribution. A future perspective of various electrochemical processes and devices that can be developed with the use of the established test station is provided.

  18. Polymorphism of calcite at high pressure and high temperature

    NASA Astrophysics Data System (ADS)

    Merlini, Marco

    2015-04-01

    Carbonates may play a fundamental role as carbon repository phases in the Earth's interior[1]. Recent crystal structure determinations by single crystal diffraction technique at high pressure [2] have shown that these phases may adopt very complex structures at pressures corresponding to Earth's upper and lower mantle. Calcite, CaCO3, transforms to low symmetry phases. Computational studies have confirmed that some of these polymorphs, CaCO3-VI in particular, are thermodynamically stable compared to calcite and aragonite. We investigated also the high temperature polymorphism, by experiments at controlled atmosphere and we confirmed the recently proposed CaCO3-V structure [3] above 1000°C and ambient pressure. In-situ experiments at simultaneous high pressure and temperature defined more accurately the phase relationship between these polymorphs and the effect of Mg and Fe substitution. 1. R. M. Hazen, A. P. Jones, J. A. Baross ed., Reviews in Mineralogy and Geochemistry, 75 (2013). 2. M. Merlini, M. Hanfland, High Pressure Research 33, 511-522 (2013). 3. N. Ishizawa et al., Scientific Reports, 3, 2832 (2013).

  19. Highly Loaded Low Pressure Turbine (LPT)

    NASA Technical Reports Server (NTRS)

    Ortiz, Milt; Dalsania, Vithal

    2001-01-01

    The goal of this study is to evaluate aspirated and non-aspirated aerodynamics on highly loaded LPT design. The objective is to increase stage loading by 30 to 50 percent without loss of efficiency for an existing low pressure turbine design. A study conducted on a NASA highly loaded multistage fan drive turbine (NASA CR-1964) indicated that end-wall bleed at the hub is a more significant parameter compared to aspirated airfoil. Based on this study, a 3-stage LPT is redesigned to 2-stage LIT with and without end-wall bleed. Both aerodynamic design and mechanical design are completed. In addition to end-wall bleed, exit guide vanes are designed with aspirated airfoils to reduce the losses. The LPT is redesigned with all constraints necessary for practical application. The benefit of the high-performance, highly loaded LPT shows up in reduced stage and part count, reduced size and weight, and reduced cost.

  20. Modelling heat transfer in high pressure food processing: a review

    Microsoft Academic Search

    Laura Otero; Pedro D. Sanz

    2003-01-01

    The most claimed advantage of high-pressure food processing as compared to thermal processing is that pressure acts instantaneously and uniformly through a mass of food independently of its size, shape or composition. Nevertheless, thermal gradients are established in the products after compression and cause inhomogeneities in the pursued pressure effect. Modelling heat transfer in high-pressure food processes can be a

  1. A picosecond high pressure gas switch

    SciTech Connect

    Cravey, W.R.; Poulsen, P.P.; Pincosy, P.A.

    1992-06-01

    Work is being done to develop a high pressure gas switch (HPGS) with picosecond risetimes for UWB applications. Pulse risetimes on the order of 200 picoseconds have been observed at 1 kHz prf and 1 atmosphere. Calculations show that switching closure times on the order of tens of picoseconds can be achieved at high pressures and higher electric fields. A voltage hold-off of 1 MV/cm has been measured at 10 atmospheres and several MV/cm appears possible with the HPGS. With these high electric field levels, energy storage of tens of Joules in a reasonably sized package is achievable. Initial HPGS performance has been characterized on the WASP pulse generator at LLNL. A detailed description of the switch used for initial testing is given. Switch recovery times of 1-ms have been measured at 1 atmosphere. Data on the switching uniformity, voltage hold-off recovery, and pulse repeatability, is presented. In addition, a physics switch model is described and results are compared with lab data.

  2. Method transfer from high-pressure liquid chromatography to ultra-high-pressure liquid chromatography. II. Temperature and pressure effects.

    PubMed

    Åsberg, Dennis; Samuelsson, Jörgen; Le?ko, Marek; Cavazzini, Alberto; Kaczmarski, Krzysztof; Fornstedt, Torgny

    2015-07-01

    The importance of the generated temperature and pressure gradients in ultra-high-pressure liquid chromatography (UHPLC) are investigated and compared to high-pressure liquid chromatography (HPLC). The drug Omeprazole, together with three other model compounds (with different chemical characteristics, namely uncharged, positively and negatively charged) were used. Calculations of the complete temperature profile in the column at UHPLC conditions showed, in our experiments, a temperature difference between the inlet and outlet of 16°C and a difference of 2°C between the column center and the wall. Through van't Hoff plots, this information was used to single out the decrease in retention factor (k) solely due to the temperature gradient. The uncharged solute was least affected by temperature with a decrease in k of about 5% while for charged solutes the effect was more pronounced, with k decreases up to 14%. A pressure increase of 500bar gave roughly 5% increase in k for the uncharged solute, while omeprazole and the other two charged solutes gave about 25, 20 and 15% increases in k, respectively. The stochastic model of chromatography was applied to estimate the dependence of the average number of adsorption/desorption events (n) and the average time spent by a molecule in the stationary phase (?s) on temperature and pressure on peak shape for the tailing, basic solute. Increasing the temperature yielded an increase in n and decrease in ?s which resulted in less skew at high temperatures. With increasing pressure, the stochastic modeling gave interesting results for the basic solute showing that the skew of the peak increased with pressure. The conclusion is that pressure effects are more pronounced for both retention and peak shape than the temperature effects for the polar or charged compounds in our study. PMID:26003622

  3. High-pressure properties inferred from normal-pressure properties

    NASA Astrophysics Data System (ADS)

    Tamarit, J. Ll; Barrio, M.; Pardo, L. C.; Negrier, P.; Mondieig, D.

    2008-06-01

    From the stable and metastable normal-pressure phase equilibria involved in two-component systems sharing compounds of the series CCl4-nBrn, n = 0,...,4, several thermodynamic properties concerning non-experimentally available phase transitions have been determined. To do so, the well-established concept of crossed isodimorphism has been considered to involve the isomorphism relationships between the low-temperature monoclinic phases as well as, for both rhombohedral and face-centred cubic, orientationally disordered phases appearing in the compounds of the series. On the basis of such relations, the thermodynamic properties of the two-phase equilibria are extrapolated as a function of mole fraction to the pure compounds for which the involved transitions do not exist at normal pressure. The obtained thermodynamic properties are used to build up the topological pressure temperature phase diagrams of the compounds of the series. The results are compared with the experimental pressure temperature phase diagrams obtained by means of density measurements as a function of pressure and temperature.

  4. DEVELOPMENT OF A HIGH-TEMPERATURE/HIGH-PRESSURE ELECTROSTATIC PRECIPITATOR

    EPA Science Inventory

    The report gives results of a laboratory test demonstrating the feasibility of electrostatic precipitation at high temperatures (to 1366 K) and pressures (to 3550 kPa): corona currents were stable at all temperatures. Detailed current/voltage characteristics under negative and po...

  5. Alternative Construction for High Pressure High Temperature Steel Catenary Risers

    Microsoft Academic Search

    Ricky Thethi; David Walters

    The design of deepwater riser systems to accommodate high pressures, temperatures and extreme environmental conditions is a major challenge in the development of floating production facilities. Current industry practice for steel catenary riser (SCR) installation is by welded construction, however SCR's are fatigue sensitive structures, requiring good quality welds to maintain system integrity throughout field life. This paper discusses the

  6. High Speed Switching Micoplasma in High Pressure Gases

    NASA Astrophysics Data System (ADS)

    Wakim, Dani; Staack, David

    2012-10-01

    Micro-plasma discharges with switching times approaching 1 ns are studied at pressures from 1 to 16 atm. Applications of these devices are robust high speed switching transistors able to withstand electric interference, high temperatures and harsh environments. Measured discharge conditions at 250 psia in Nitrogen are: gas temperature 2900 K, discharge diameter ˜7 ?m and electron density ˜10^17 cm-3. High speed switching is achieved by taking advantage of rapid dynamics of instabilities at high pressure and high electron density. The capacitance and inductance of the circuit also significantly affect transients. Tradeoffs are observed in switching times. By reducing capacitances from 10 pF to ˜1pF attainment of steady state conditions can be reduced from 1 us to ˜ 20 ns. However current rise times increase from 1 ns at high capacitance to 20 ns at low capacitance. A decrease in switching time with increased pressure is also observed. Also investigated are configurations with a third electrode acting as a gate or trigger and various high temperature (>2000K) materials such as platinum rhodium alloys and ceria stabilized zirconia ceramics for device fabrication.

  7. Liquid Rocket Lines, Bellows, Flexible Hoses, and Filters

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Fluid-flow components in a liquid propellant rocket engine and the rocket vehicle which it propels are interconnected by lines, bellows, and flexible hoses. Elements involved in the successful design of these components are identified and current technologies pertaining to these elements are reviewed, assessed, and summarized to provide a technology base for a checklist of rules to be followed by project managers in guiding a design or assessing its adequacy. Recommended procedures for satisfying each of the design criteria are included.

  8. High-pressure coal fuel processor development

    SciTech Connect

    Greenhalgh, M.L.

    1992-11-01

    The objective of Subtask 1.1 Engine Feasibility was to conduct research needed to establish the technical feasibility of ignition and stable combustion of directly injected, 3,000 psi, low-Btu gas with glow plug ignition assist at diesel engine compression ratios. This objective was accomplished by designing, fabricating, testing and analyzing the combustion performance of synthesized low-Btu coal gas in a single-cylinder test engine combustion rig located at the Caterpillar Technical Center engine lab in Mossville, Illinois. The objective of Subtask 1.2 Fuel Processor Feasibility was to conduct research needed to establish the technical feasibility of air-blown, fixed-bed, high-pressure coal fuel processing at up to 3,000 psi operating pressure, incorporating in-bed sulfur and particulate capture. This objective was accomplished by designing, fabricating, testing and analyzing the performance of bench-scale processors located at Coal Technology Corporation (subcontractor) facilities in Bristol, Virginia. These two subtasks were carried out at widely separated locations and will be discussed in separate sections of this report. They were, however, independent in that the composition of the synthetic coal gas used to fuel the combustion rig was adjusted to reflect the range of exit gas compositions being produced on the fuel processor rig. Two major conclusions resulted from this task. First, direct injected, ignition assisted Diesel cycle engine combustion systems can be suitably modified to efficiently utilize these low-Btu gas fuels. Second, high pressure gasification of selected run-of-the-mine coals in batch-loaded fuel processors is feasible. These two findings, taken together, significantly reduce the perceived technical risks associated with the further development of the proposed coal gas fueled Diesel cycle power plant concept.

  9. Very high temperature silicon on silicon pressure transducers

    NASA Technical Reports Server (NTRS)

    Kurtz, Anthony D.; Nunn, Timothy A.; Briggs, Stephen A.; Ned, Alexander

    1992-01-01

    A silicon on silicon pressure sensor has been developed for use at very high temperatures (1000 F). The design principles used to fabricate the pressure sensor are outlined and results are presented of its high temperature performance.

  10. High Blood Pressure in Pregnancy - Multiple Languages: MedlinePlus

    MedlinePLUS

    ... ???? ????? ????? - ??????? Bilingual PDF Health Information Translations Bosnian (Bosanski) High Blood Pressure in Pregnancy Visok ... u trudno?i - Bosanski (Bosnian) Bilingual PDF Health Information Translations Chinese - Simplified (????) High Blood Pressure in Pregnancy ...

  11. Single crystal electrical resistivity of magnetite under high pressure

    NASA Astrophysics Data System (ADS)

    Muramatsu, Takaki; Helmuth Berger Collaboration; Lev V Gasparov Collaboration; Viktor V. Struzhkin Collaboration; Russell J. Hemley Collaboration

    2015-03-01

    Magnetite (Fe3O4), the oldest known magnetic mineral has the cubic inversed spinel structure at ambient pressure and temperature. It shows a metal to insulator transition (Verway transition) at about 125 K as temperature decreases at ambient pressure. Under high pressure the Verwey transition is suppressed down to 0 K and above 25 GPa magnetite undergoes a structural transformation to high pressure phase. These behaviors have been intensively examined by various experimental means and computational calculations for decades. However only the limited number of the electrical resistivity measurements on single crystal magnetite under pressure have been performed at the moment. We performed high pressure and low temperature experiments by means of the electrical resistivity on single crystal magnetite to examine Verwey transition under pressure and a structural transformation from cubic spinel phase to high pressure phase. We report the results of the temperature dependence of the electrical resistivity in the pressure range from ambient pressure to more than 50 GPa.

  12. High-pressure Raman spectroscopy of diamond anvils to 250 GPa: Method for pressure determination in the multimegabar pressure range

    NASA Astrophysics Data System (ADS)

    Akahama, Yuichi; Kawamura, Haruki

    2004-10-01

    The first-order Raman spectra of diamond anvils used in a gasketed high-pressure cell have been measured at pressure up to 250GPa. The high-frequency edge of the Raman band, which corresponds to the Raman shift of the culet face, is represented by a function of pressure in the sample chamber up to 250GPa. The dependence is almost independent on loading conditions. The application of the pressure dependence for pressure determination up to the multimegabars pressure region is proposed.

  13. High pressure-resistant nonincendive emulsion explosive

    DOEpatents

    Ruhe, Thomas C. (Duquesne, PA); Rao, Pilaka P. (Baghlingampalli, IN)

    1994-01-01

    An improved emulsion explosive composition including hollow microspheres/bulking agents having high density and high strength. The hollow microspheres/bulking agents have true particle densities of about 0.2 grams per cubic centimeter or greater and include glass, siliceous, ceramic and synthetic resin microspheres, expanded minerals, and mixtures thereof. The preferred weight percentage of hollow microspheres/bulking agents in the composition ranges from 3.0 to 10.0 A chlorinated paraffin oil, also present in the improved emulsion explosive composition, imparts a higher film strength to the oil phase in the emulsion. The emulsion is rendered nonincendive by the production of sodium chloride in situ via the decomposition of sodium nitrate, a chlorinated paraffin oil, and sodium perchlorate. The air-gap sensitivity is improved by the in situ formation of monomethylamine perchlorate from dissolved monomethylamine nitrate and sodium perchlorate. The emulsion explosive composition can withstand static pressures to 139 bars and dynamic pressure loads on the order of 567 bars.

  14. High-pressure coal fuel processor development

    SciTech Connect

    Greenhalgh, M.L.; Wen, C.S.; Smith, L.

    1992-01-01

    Caterpillar shares DOE/METC interest in demonstrating the technology required to displace petroleum-based engine fuels with various forms of low cost coal. Current DOE/METC programs on mild gasification and coal-water-slurries are addressing two approaches to this end. Engine and fuel processor system concept studies by Caterpillar have identified a third, potentially promising, option. This option includes high-pressure fuel processing of run-of-the-mine coal and direct injection of the resulting low-Btu gas stream into an ignition assisted, high compression ratio diesel engine. The compactness and predicted efficiency of the system make it suitable for application to line-haul railroad locomotives. A successful conclusion of the program will enable further component development work and full-scale system demonstrations of this potentially important technology. This paper covers the work on fuel processor rig testing completed in FY92.

  15. High-pressure coal fuel processor development

    SciTech Connect

    Greenhalgh, M.L.; Wen, C.S.; Smith, L.

    1992-12-31

    Caterpillar shares DOE/METC interest in demonstrating the technology required to displace petroleum-based engine fuels with various forms of low cost coal. Current DOE/METC programs on mild gasification and coal-water-slurries are addressing two approaches to this end. Engine and fuel processor system concept studies by Caterpillar have identified a third, potentially promising, option. This option includes high-pressure fuel processing of run-of-the-mine coal and direct injection of the resulting low-Btu gas stream into an ignition assisted, high compression ratio diesel engine. The compactness and predicted efficiency of the system make it suitable for application to line-haul railroad locomotives. A successful conclusion of the program will enable further component development work and full-scale system demonstrations of this potentially important technology. This paper covers the work on fuel processor rig testing completed in FY92.

  16. Integrated optimization system for high pressure die casting processes

    Microsoft Academic Search

    L. X. Kong; F. H. She; W. M. Gao; S. Nahavandi; P. D. Hodgson

    2008-01-01

    High pressure die casting (HPDC) is a versatile process for producing engineered metal parts by forcing molten metal under high pressure into reusable steel dies. However there are a large number of attributes involved which contribute to the complexity of the process. A novel integrated approach is developed to optimize the high pressure die casting processes. The die temperature profiles

  17. Microwave interferometry for high pressure non-thermal pulsed plasma

    Microsoft Academic Search

    Xinpei Lu; M. Laroussi

    2008-01-01

    Summary form only given. Atmospheric pressure non-equilibrium plasmas are now used in many applications including those where low-pressure plasmas have traditionally been used. However, measurements of key plasma parameters in the highly collisional regime exhibited at atmospheric pressure offer challenges, which usually have to satisfy requirements that are different than those found at low pressures. In this paper, a millimeter

  18. High-pressure coal fuel processor development

    SciTech Connect

    Greenhalgh, M.L. (Caterpillar, Inc., Peoria, IL (United States))

    1992-12-01

    Caterpillar shares DOE/METC interest in demonstrating the technology required to displace petroleum-based engine fuels with various forms of low cost coal. Current DOE/METC programs on mild gasification and coal-water-slurries are addressing two approaches to this end. Engine and fuel processor system concept studies by Caterpillar have identified a third, potentially promising, option. This option includes high-pressure fuel processing of run-of-the-mine coal and direct injection of the resulting low-Btu gas stream into an ignition assisted, high compression ratio diesel engine. The compactness and predicted efficiency of the system make it suitable for application to line-haul railroad locomotives. Two overall conclusions resulted from Task 1. First direct injected, ignition assisted Diesel cycle engine combustion systems can be suitably modified to efficiently utilize low-Btu gas fuels. Second, high pressure gasification of selected run-of-the-mine coals in batch-loaded fuel processors is feasible. These two findings, taken together, significantly reduce the perceived technical risk associated with the further development of the proposed coal gas fueled Diesel cycle power plant concept. The significant conclusions from Task 2 were: An engine concept, derived from a Caterpillar 3600 series engine, and a fuel processor concept, based on scaling up a removable-canister configuration from the test rig, appear feasible; and although the results of this concept study are encouraging, further, full-scale component research and development are required before attempting a full-scale integrated system demonstration effort.

  19. High pressure sorption isotherms via differential pressure measurements

    Microsoft Academic Search

    John M. Zielinski; Charles G. Coe; Randy J. Nickel; Anthony M. Romeo; Alan C. Cooper; Guido P. Pez

    2007-01-01

    A differential pressure adsorption unit (DPAU) has been constructed which is capable of accurately measuring isotherm data\\u000a up to 2000 psia with as little as 100 mg of sample. This non-traditional adsorption\\/desorption method has been benchmarked\\u000a by comparing hydrogen and methane isotherms measured with standard volumetric and gravimetric instruments on a NaA (4A) zeolite\\u000a and an activated carbon at near

  20. 49 CFR 192.197 - Control of the pressure of gas delivered from high-pressure distribution systems.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...false Control of the pressure of gas delivered from high-pressure distribution...PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY...197 Control of the pressure of gas delivered from high-pressure...

  1. 49 CFR 192.197 - Control of the pressure of gas delivered from high-pressure distribution systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...false Control of the pressure of gas delivered from high-pressure distribution...PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY...197 Control of the pressure of gas delivered from high-pressure...

  2. 49 CFR 192.197 - Control of the pressure of gas delivered from high-pressure distribution systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...false Control of the pressure of gas delivered from high-pressure distribution...PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY...197 Control of the pressure of gas delivered from high-pressure...

  3. 49 CFR 192.197 - Control of the pressure of gas delivered from high-pressure distribution systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...false Control of the pressure of gas delivered from high-pressure distribution...PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY...197 Control of the pressure of gas delivered from high-pressure...

  4. High-Pressure X-ray Tomography Microscope: Synchrotron Computed Microtomography at High Pressure and Temperature

    SciTech Connect

    Wang, Y.; Uchida, T.; Westferro, F.; Rivers, M.L.; Gebhardt, J.; Lesher, C.E.; Sutton, S.R. (UCD); (UC)

    2010-07-20

    A new apparatus has been developed for microtomography studies under high pressure. The pressure generation mechanism is based on the concept of the widely used Drickamer anvil apparatus, with two opposed anvils compressed inside a containment ring. Modifications are made with thin aluminum alloy containment rings to allow transmission of x rays. Pressures up to 8 GPa have been generated with a hydraulic load of 25 T. The modified Drickamer cell is supported by thrust bearings so that the entire pressure cell can be rotated under load. Spatial resolution of the high pressure tomography apparatus has been evaluated using a sample containing vitreous carbon spheres embedded in FeS matrix, with diameters ranging from 0.01 to 0.2 mm. Spheres with diameters as small as 0.02 mm were well resolved, with measured surface-to-volume ratios approaching theoretical values. The sample was then subject to a large shear strain field by twisting the top and bottom Drickamer anvils. Imaging analysis showed that detailed microstructure evolution information can be obtained at various steps of the shear deformation, allowing strain partition determination between the matrix and the inclusions. A sample containing a vitreous Mg{sub 2}SiO{sub 4} sphere in FeS matrix was compressed to 5 GPa, in order to evaluate the feasibility of volume measurement by microtomography. The results demonstrated that quantitative inclusion volume information can be obtained, permitting in situ determination of P-V-T equation of state for noncrystalline materials.

  5. Design and development of a high resolution differential pressure transducer for use at high temperature and high pressure

    E-print Network

    Childers, Laren Paul

    1984-01-01

    DATA FOR THE EXTERNAL COIL LVDT DPT APPENDIX B TEMPERATURE AND PRESSURE DEPENDENCY DATA VITA 85 87 90 LIST OF FIGURES FIGURE Page 1 A highly sensitive electronic bridge for use with a capacitor detection system. 2 An electronic bridge... tube sensing element DPT. 10 5 A DPT designed by Osburn (1981) with a protected bellows sensing element, and an external coil LVDT detection system. 6 A high precision DPT manufactured by the Ruska Corporation for use at high pressure and low...

  6. Calculating Mass Diffusion in High-Pressure Binary Fluids

    NASA Technical Reports Server (NTRS)

    Bellan, Josette; Harstad, Kenneth

    2004-01-01

    A comprehensive mathematical model of mass diffusion has been developed for binary fluids at high pressures, including critical and supercritical pressures. Heretofore, diverse expressions, valid for limited parameter ranges, have been used to correlate high-pressure binary mass-diffusion-coefficient data. This model will likely be especially useful in the computational simulation and analysis of combustion phenomena in diesel engines, gas turbines, and liquid rocket engines, wherein mass diffusion at high pressure plays a major role.

  7. Effect of high pressure on structural oddities 

    E-print Network

    Johnstone, Russell D. L.

    2010-01-01

    This thesis describes the effect of pressure on crystal structures that are in some way unusual. The aim was to investigate whether pressure could be used to force these ‘structural oddities’ to conform to more conventional ...

  8. High pressure fiber optic sensor system

    DOEpatents

    Guida, Renato; Xia, Hua; Lee, Boon K; Dekate, Sachin N

    2013-11-26

    The present application provides a fiber optic sensor system. The fiber optic sensor system may include a small diameter bellows, a large diameter bellows, and a fiber optic pressure sensor attached to the small diameter bellows. Contraction of the large diameter bellows under an applied pressure may cause the small diameter bellows to expand such that the fiber optic pressure sensor may measure the applied pressure.

  9. Thermal expansion of Mg(OH) 2 brucite under high pressure and pressure dependence of entropy

    Microsoft Academic Search

    H. Fukui; O. Ohtaka; T. Suzuki; K. Funakoshi

    2003-01-01

    An equation of state for Mg(OH) 2 brucite under high-pressure and high-temperature conditions has been obtained by measuring temperature dependence of volume up to 600 K at ambient pressure and pressure dependence of volume up to 16 GPa at 300, 473, 673, and 873 K with in situ X-ray diffraction. Pressure dependence of entropy of brucite has been calculated with

  10. Filament wound pressure vessels - Effects of using liner tooling of low pressure vessels for high pressure vessels development

    Microsoft Academic Search

    Krishna M. Lal

    1992-01-01

    High performance pressure vessels have been recently demanded for aerospace and defense applications. Filament wound pressure vessels consist of a metallic thin liner, which also acts as a mandrel, and composite\\/epoxy overwrap. Graphite\\/epoxy overwrapped vessels have been developed to obtain the performance ratio, PV\\/W, as high as one million inches. Under very high pressure the isotropic metallic liner deforms elasto-plastically,

  11. Portable apparatus for loading turnbuckle pressure cells with high pressure gases

    Microsoft Academic Search

    S. W. Tozer

    2012-01-01

    For high pressure work on high-purity metals that are very susceptible to any degree strain resulting from non-hydrostaticity, we have developed a portable apparatus for loading high pressure gases into turnbuckle style anvil cells (such as sapphire ball or SiC, diamond or sapphire anvil). The apparatus can be used with conventional high pressure intensifier systems that operate at room temperature,

  12. Anorthite - Thermal equation of state to high pressures

    Microsoft Academic Search

    Raymond Jeanloz; Thomas J. Ahrens

    1980-01-01

    New shock-wave data are presented for anorthite from which a full high-temperature, high-pressure equation of state is derived. Whereas anorthite has relatively low values of thermal expansion and Grueneisen parameter at zero pressure, it is found that these attain relatively high values in the high density state corresponding to the high-pressure phase Hugoniot but decrease upon compression as expected. It

  13. Ceramic cells for high pressure NMR spectroscopy of proteins

    NASA Astrophysics Data System (ADS)

    Erlach, Markus Beck; Munte, Claudia E.; Kremer, Werner; Hartl, Rainer; Rochelt, Dörte; Niesner, Dieter; Kalbitzer, Hans Robert

    2010-06-01

    Application of high pressure to biological macromolecules can be used to find new structural states with a smaller specific volume of the system. High pressure NMR spectroscopy is a most promising analytical tool for the study of these states at atomic resolution. High pressure quartz cells are difficult to handle, high quality sapphire high pressure cells are difficult to obtain commercially. In this work, we describe the use of high pressure ceramic cells produced from yttrium stabilized ZrO 2 that are capable of resisting pressures up to 200 MPa. Since the new cells should also be usable in the easily damageable cryoprobes a completely new autoclave for these cells has been constructed, including an improved method for pressure transmission, an integrated safety jacket, a displacement body, and a fast self-closing emergency valve.

  14. Deaths from High Blood Pressure Should Plummet Under 'Obamacare': Study

    MedlinePLUS

    Deaths From High Blood Pressure Should Plummet Under 'Obamacare': Study Researchers estimate access to treatment could save ... 2015 THURSDAY, July 9, 2015 (HealthDay News) -- U.S. deaths from blood pressure-related diseases are expected to ...

  15. High Pressure Rotary Shaft Sealing Mechanism

    DOEpatents

    Dietle, Lannie (Sugar Land, TX); Gobeli, Jeffrey D. (Houston, TX)

    2001-05-08

    A laterally translatable pressure staged rotary shaft sealing mechanism having a seal housing with a shaft passage therein being exposed to a fluid pressure P1 and with a rotary shaft being located within the shaft passage. At least one annular laterally translatable seal carrier is provided. First and second annular resilient sealing elements are supported in axially spaced relation by the annular seal carriers and have sealing relation with the rotary shaft. The seal housing and at least one seal carrier define a first pressure staging chamber exposed to the first annular resilient sealing element and a second pressure staging chamber located between and exposed to the first and second annular resilient sealing elements. A first fluid is circulated to the first pressure chamber at a pressure P1, and a second staging pressure fluid is circulated to the second pressure chamber at a fraction of pressure P1 to achieve pressure staging, cooling of the seals. Seal placement provides hydraulic force balancing of the annular seal carriers.

  16. Two-Phase Flow and Heat Transfer During Chilldown of a Simulated Flexible Metal Hose Using Liquid Nitrogen

    NASA Astrophysics Data System (ADS)

    Hu, Hong; Wijeratne, Thilan K.; Chung, J. N.

    2014-03-01

    For many industrial, medical and space technologies, cryogenic fluids play irreplaceable roles. When any cryogenic system is initially started, it must go through a transient chill down period prior to normal operation. Chilldown is the process of introducing the cryogenic liquid into the system, and allowing the system components to cool down to several hundred degrees below the ambient temperature. The chilldown process is an important initial stage before a system begins functioning. The objective of this paper is to investigate the chilldown process associated with a flexible hose that was simulated by a channel with saw-teeth inner wall surface structure in the current study. We have investigated the fundamental physics of the two-phase flow and quenching heat transfer during cryogenic chilldown inside the simulated flexible hose through flow visualization, data measurement and analysis. The flow pattern developed inside the channel was recorded by a high speed camera for flow pattern investigation. The experimental results indicate that the chilldown process that is composed of unsteady vapor-liquid two-phase flow and phase-change heat transfer is modified by the inner wall surface wavy structure. Based on the measurement of the channel wall temperature, the teeth structure and the associated cavities generally reduce the heat transfer efficiency compared to the straight hose. Furthermore, based on the measured data, a complete series of correlations on the heat transfer coefficient for each heat transfer regime was developed and reported.

  17. High-pressure study of neptunium and plutonium compounds

    Microsoft Academic Search

    S. Dabos-Seignon; U. Benedict

    1990-01-01

    Neptunium and plutonium monopnictides and monochalcogenides were studied by x-ray diffraction at pressures up to 57 GPa. All of them exhibit structural phase transitions under pressure. The arsenides and tellurides have a CsCl (B2) type high-pressure structure. Sb as an anion favours a tetragonal high-pressure structure. The compressibilities were determined for all of the compounds studied. The results are compared

  18. High pressure high temperature elasticity study of sodium disilicate glass

    NASA Astrophysics Data System (ADS)

    Yu, T.; Kono, Y.; Sakamaki, T.; Jing, Z.; Wang, Y.; Shen, G.

    2011-12-01

    Many deep earth geophysical phenomena observed are related to physical properties of silicate melts under extreme conditions. Understanding the structures and physical properties of silicate melts at a fundamental level is essential to help us understand the dynamics of mineral crystallization and fractionation, thermal transport, etc. inside the Earth. Sodium disilicate (Na2Si2O5) glass is a good analog for studying amorphous phase basalt since they have similar ratios of non-bridging oxygen to tetrahedrally coordinated cations (NBO/T). Besides, sodium disilicate is not only simple in chemistry but also has a low melting point, thus permitting detailed experimental studies using currently available techniques. Synthesized sodium disilicate glass was ground into powder and loaded into a Paris-Edinburgh (PE) cell. The PE high pressure apparatus was installed inside the 16-BM-B hutch at the Advanced Photon Source. In our experiment, the glass sample was pressed up to 2GPa and heated up to 1000oC. At various pressure and temperature conditions, ultrasonic elastic wave velocities of the amorphous sample were collected using the pulse reflection method with a 10o Y-cut LiNbO3 transducer mounted on one end of the PE anvil. White beam x-ray radiographs that covered the entire length of the sample were also collected to determine the elastic wave travel distance. Experimental results show that before the glass transition temperature (~700oC at ambient pressure), the transverse wave velocity remains nearly constant with increasing temperature, while the longitudinal wave velocity decreases monotonically. A sudden drop in transverse wave velocity is observed above the glass transition temperature at 800oC. Within the 2GPa pressure range, we did not observe clear pressure dependence of the elastic wave velocities in sodium disilicate glass.

  19. Performance of gas-atomized spray scrubbers at high pressure

    SciTech Connect

    Yung, S.C.

    1984-07-01

    Many pressurised coal gasification processes under development propose using Venturi scrubbers for particulate removal at high pressures. Theoretical predictions based on models indicate that particle collection efficiency will decrease severely in these high gas pressure applications. A study of the effect of gas pressure on Venturi scrubber performance is reported. Experiments were carried out on a 0.47 m/sup 3//s pilot scale Venturi scrubber. Particle collection performance was determined as a function of scrubber pressure drop in the range 1-10 atm total pressure. Results confirmed that the particle collection efficiency of Venturi scrubbers decreases for a given scrubber pressure drop as total gas pressure is increased. In order to achieve the same particle collection efficiency, the pressure drop across a Venturi scrubber operated at 10 atm is about 10 times that of the same scrubber operated at 1 atm pressure.

  20. High Temperature High Pressure Thermodynamic Measurements for Coal Model Compounds

    SciTech Connect

    John C. Chen; Vinayak N. Kabadi

    1998-11-12

    The overall objective of this project is to develop a better thermodynamic model for predicting properties of high-boiling coal derived liquids, especially the phase equilibria of different fractions at elevated temperatures and pressures. The development of such a model requires data on vapor-liquid equilibria (VLE), enthalpy, and heat capacity which would be experimentally determined for binary systems of coal model compounds and compiled into a database. The data will be used to refine existing models such as UNIQUAC and UNIFAC. The flow VLE apparatus designed and built for a previous project was upgraded and recalibrated for data measurements for thk project. The modifications include better and more accurate sampling technique and addition of a digital recorder to monitor temperature, pressure and liquid level inside the VLE cell. VLE data measurements for system benzene-ethylbenzene have been completed. The vapor and liquid samples were analysed using the Perkin-Elmer Autosystem gas chromatography.

  1. High-pressure balloon catheter for real-time pressure monitoring in the esophagus

    Microsoft Academic Search

    K. Y. Kwan; K. V. I. S. Kaler; M. P. Mintchev

    2002-01-01

    This paper reports the development of a new catheter for esophageal manometry, implemented by connecting a miniature high-pressure sensing balloon to an external pressure sensor. The integration of the catheter into a signal conditioning and data acquisition system for realtime pressure monitoring is also described. In order to characterize the sensitivity of the novel self-contained air balloon design, an experimental

  2. Is high pulse pressure a marker of preclinical cardiovascular disease?

    PubMed

    de Simone, Giovanni; Roman, Mary J; Alderman, Michael H; Galderisi, Maurizio; de Divitiis, Oreste; Devereux, Richard B

    2005-04-01

    This study tests the hypothesis that high brachial pulse pressure might constitute preclinical cardiovascular disease, rather than a risk factor. We studied 1250 subjects (472 nonobese normotensive [<135/80 mm Hg] and 778 untreated hypertensive). Central pulse pressure was estimated from brachial pulse pressure and age and divided by stroke volume (PP/SV). Brachial pulse pressure was considered high when >63 mm Hg, and peripheral resistance high when >90th percentile of normal distribution. Among hypertensive subjects, 34% had high resistance; among them, 33% had high brachial pulse pressure, as opposed to 147 of 516 patients (28.5%) with normal resistance (P=not significant). After adjusting for age, sex, race, body mass index, heart rate, and center, left ventricular (LV) internal dimension and mass were lower with high resistance, and higher when brachial pulse pressure was high. PP/SV was 36% higher with high resistance than with normal resistance, and higher when brachial pulse pressure was high (all P<0.0001). Factorial analysis demonstrated that associations of high brachial pulse pressure with both higher PP/SV and LV mass were independent of other pressure components. Thus, because of these associations, our hypothesis is that in hypertension, pulse pressure may be considered as a marker of preclinical cardiovascular disease, similar to LV mass and PP/SV, rather than a cardiovascular risk factor. PMID:15767471

  3. Anorthite - Thermal equation of state to high pressures

    NASA Technical Reports Server (NTRS)

    Jeanloz, R.; Ahrens, T. J.

    1980-01-01

    New shock-wave data are presented for anorthite from which a full high-temperature, high-pressure equation of state is derived. Whereas anorthite has relatively low values of thermal expansion and Grueneisen parameter at zero pressure, it is found that these attain relatively high values in the high density state corresponding to the high-pressure phase Hugoniot but decrease upon compression as expected. It is noted that higher order anharmonic contributions decrease more rapidly with pressure and that the thermal expansion therefore saturates to a high temperature value at pressures above about 100 GPa. Reduction of the Hugoniot data permits shock temperatures to be calculated; it also yields a principal adiabat for the high pressure branch of the Hugoniot. The initial bulk modulus of this adiabat is essentially identical to that of anorthite, whereas the initial density is about 3.40 Mg/cu m.

  4. Neutron powder diffraction under high pressure at J-PARC

    NASA Astrophysics Data System (ADS)

    Utsumi, Wataru; Kagi, Hiroyuki; Komatsu, Kazuki; Arima, Hiroshi; Nagai, Takaya; Okuchi, Takuo; Kamiyama, Takashi; Uwatoko, Yoshiya; Matsubayashi, Kazuyuki; Yagi, Takehiko

    2009-02-01

    It is expected that high-pressure material science and the investigation of the Earth's interior will progress greatly using the high-flux pulse neutrons of J-PARC. In this article, we introduce our plans for in situ neutron powder diffraction experiments under high pressure at J-PARC. The use of three different types of high-pressure devices is planned; a Paris-Edinburgh cell, a new opposed-anvil cell with a nano-polycrystalline diamond, and a cubic anvil high-pressure apparatus. These devices will be brought to the neutron powder diffraction beamlines to conduct a "day-one" high-pressure experiment. For the next stage of research, we propose construction of a dedicated beamline for high-pressure material science. Its conceptual designs are also introduced here.

  5. The influence of pressure during solidification of high pressure die cast aluminium telecommunications components

    Microsoft Academic Search

    Matthew S. Dargusch; G. Dour; N. Schauer; C. M. Dinnis; G. Savage

    2006-01-01

    The effects of process variables on the quality of high-pressure die cast components was determined with the aid of in-cavity pressure sensors. In particular, the effects of set intensification pressure, delay time, and casting velocity have been investigated. The in-cavity pressure sensor has been used to determine how conditions within the die-cavity are related to the process parameters regulated by

  6. Studies of basic mechanisms in high pressure gases: Applications to high efficiency high power lasers

    NASA Technical Reports Server (NTRS)

    Verdeyen, J. T.; Cherrington, B. E.; Leslie, S. G.; Millar, W. S.; Edwards, B. E.

    1976-01-01

    A high power pulsed dye laser was used to optically excite high pressure cesium-xenon mixtures and the resulting measurements are presented. A microwave discharge in rubidium at relatively high xenon pressure was achieved. Preliminary studies of cadium-rare gas mixtures are discussed and a detailed description of the entire experimental apparatus is given.

  7. What Is High Blood Pressure Medicine?

    MedlinePLUS

    ... there? • DIURETICS rid the body of excess sodium (salt) and water and help control blood pressure. • BETA BLOCKERS reduce the heart rate and the ... make the other lifestyle changes that help reduce blood pressure ... sodium (salt) intake, being more regularly physically active and limiting ...

  8. High Blood Pressure and Kidney Disease

    MedlinePLUS

    ... Kidney disease is diagnosed with urine and blood tests. Health care providers measure blood pressure with a blood pressure ... the sample to a lab for analysis. A health care provider may order a blood test to estimate how much blood the kidneys filter ...

  9. Single stage high pressure centrifugal slurry pump

    DOEpatents

    Meyer, John W. (Palo Alto, CA); Bonin, John H. (Sunnyvale, CA); Daniel, Arnold D. (Alameda, CA)

    1984-03-27

    Apparatus is shown for feeding a slurry to a pressurized housing. An impeller that includes radial passages is mounted in the loose fitting housing. The impeller hub is connected to a drive means and a slurry supply means which extends through the housing. Pressured gas is fed into the housing for substantially enveloping the impeller in a bubble of gas.

  10. Ultra-high Pressure Minerals in Ophiolites

    NASA Astrophysics Data System (ADS)

    Robinson, P. T.; Bai, W.; Yang, J.; Fang, Q.

    2004-12-01

    Most ultra-high pressure (UHP) minerals are found in kimberlites, deeply subducted continental crustal rocks and meteorites or meteorite impact craters. Graphitized diamonds have been found in subcontinental peridotites of the Ronda and Beni Boursera massifs. Numerous UHP minerals have also been reported from ophiolites, particularly in Russia, Indonesia, Canada, the USA and China. Many of these reported discoveries are from placer deposits and the origin of the UHP minerals has not been confirmed. The best documented occurrence of an UHP mineral-bearing ophiolite is the Luobusa ophiolite, which lies in the Yarlung-Zangbo suture zone of southern Tibet. A wide variety of UHP minerals, including diamond, moissanite, coesite, Fe-silicides, wüstite, silicon rutile, silicon spinel, and CrC alloys, has been recovered from podiform chromitites in Luobusa. These minerals are associated with native elements, such as Si, Fe, Ti, and Cr, and with PGE alloys, some of which may also have an UHP origin. Diamonds have also been reported from the Donqiao ophiolite of the Nujiang-Bangong Lake suture zone in central Tibet but this occurrence as not been confirmed. The demonstrated occurrence of UHP minerals in Luobusa and the reported occurrences from other bodies suggest that ophiolites may be common repositories of UHP minerals.

  11. High Pressure Source/Cryostat Relief Solutions

    SciTech Connect

    Wintercorn, S.J.; Mulholland, G.T.; /Fermilab

    1987-08-13

    This report addresses solutions to the potential problem of cryostat over pressurization by the nominal 65 psi MWAP LAr source dewar. Uncontrolled (by reason of failure) filling of a 15 psi MW AP cryostat by the LAr fill line could cause over pressurization by overwhelming the provided cryostat relief system. Three levels of protection against over pressurization by the source dewar are mentioned in this report; the reduced (operational) relief pressure, the source pressure regulator, and the LAr dewar cooling loop. Only the first of these is recognized by the ASME code as sufficient protection, the others provide operational convenience and avoid the loss of detector fluid. Flow limiting device solutions are not considered because of the conflicting requirement to empty and fill the cryostats rapidly (within one eight hour shift), e.g. the movement of the cryostat from the assembly hall to the collision hall, or the inverse operation.

  12. Selected studies of magnetism at high pressure

    SciTech Connect

    Hearne, G.R. [University of the Witwatersrand, Johannesburg (South Africa). Dept. of Physics; Pasternak, M.P. [Tel-Aviv Univ. (Israel). School of Physics and Astronomy; Taylor, R.D. [Los Alamos National Lab., NM (United States)

    1995-09-01

    Most previous studies of magnetism in various compounds under extreme conditions have been conducted over a wide pressure range at room temperature or over a wide range of cryogenic temperatures at pressures below 20 GPa (200 kbar). We present some of the most recent studies of magnetism over an extended range of temperatures and pressures far beyond 20 GPa, i.e., in regions of pressure-temperature (P-T) where magnetism has been largely unexplored. Recent techniques have permitted investigations of magnetism in selected 3d transition metal compounds in regions of P-T where physical properties may be drastically modified; related effects have often been seen in selected doping studies at ambient pressures.

  13. HIGH TEMPERATURE HIGH PRESSURE THERMODYNAMIC MEASUREMENTS FOR COAL MODEL COMPOUNDS

    SciTech Connect

    Vinayak N. Kabadi

    1999-02-20

    It is well known that the fluid phase equilibria can be represented by a number of {gamma}-models , but unfortunately most of them do not function well under high temperature. In this calculation, we mainly investigate the performance of UNIQUAC and NRTL models under high temperature, using temperature dependent parameters rather than using the original formulas. the other feature of this calculation is that we try to relate the excess Gibbs energy G{sup E}and enthalpy of mixing H{sup E}simultaneously. In other words, we will use the high temperature and pressure G{sup E} and H{sup E}data to regress the temperature dependant parameters to find out which model and what kind of temperature dependant parameters should be used.

  14. Technical Evaluation for the Determination of CGI Designation for Safety Class Items Incorporated in Hose-in-Hose Transfer Line Assemblies

    SciTech Connect

    BUCHANAN, J.R.

    2000-05-16

    The purpose of this technical evaluation is to determine whether the secondary hoses are to be categorized as Commercial Grade Items (CGI) or Engineered Equipment. This determination will identify whether or not use of the CGI Dedication process is appropriate.

  15. Elastic properties of anorthite at high temperature and high pressure

    NASA Astrophysics Data System (ADS)

    Matsukage, K. N.; Nishihara, Y.; Noritake, F.; Tsujino, N.; Sakurai, M.; Higo, Y.; Kawamura, K.; Takahashi, E.

    2012-12-01

    To understand the elastic properties of subducted crustal minerals at P-T conditions of crust and upper most mantle, we performed in situ measurement of the elastic wave velocities of anorthite at temperatures up to 1100 oC at less than 2.0 GPa (in stability field) and up to 500 oC at 2.0-7.0 GPa. A fine grained polycrystalline anorthite was synthesised by using gas pressure apparatus installed at magma factory in Tokyo Institute of Technology. The quenched glass with anorthite composition was ground in ethanol and was loaded into a sealed Pt tube (3.0 mm inner diameter and 0.2 mm thickness) container. The sample was preheated at 900°C for 2 hours, and then keep at 1100°C for 20 hours at pressure of 0.3 GPa. The maximum grain size of the synthesized polycrystalline anorthite was about 15?m. The experiments were performed using the SPEED-1500 apparatus installed on beam line BL04B1 at synchrotron facility of SPring-8, Japan (Utsumi et al. 1998). The experimental design for in situ elastic wave velocities measurement at BL04B1 was presented by Higo et al. (2009). Pressure was generated by eight 26 mm tungsten carbide anvils with 11 mm truncated edge length. A Co-doped semi-sintered MgO octahedron with an 18 mm edge length was used as a pressure medium. The sample was enclosed in a BN sleeve container, and was placed in the central part (hot spot) of the furnace. Platinum foils (2.5 ?m in thickness) were inserted at the both side of the sample for determination of sample length by using X-ray radiographic imaging techniques. An Al2O3 rod (5.3 mm in length and 2.0 mm in diameter) was used as buffer rod which transmit ultrasonic wave to the sample. Temperature was measured by a W97Re3-W75Re25 thermocouple. MgO was used as a pressure marker, and it was mixed with BN (MgO:BN = 1:1 by weight) to prevent grain growth at high temperatures. The ultrasonic signals were generated and received by 10oY-cut LiNbO3 transducer of 50 ?m in thickness and 3.2 mm in diameter. We used the ultrasonic wave of the frequencies 30-60MHz with 3-5cycle. The P and S wave velocities of anorthite at room pressure and temperature calculated by using our data are 7.01 km/s and 3.75 km/s, respectively. In this study, we found a drop of elastic wave velocities at ~240oC in <2.5GPa, and gradual decrease of the velocities in >3GPa and <500oC. These velocity changes are considered to be caused by the elastic softening by the phase transitions from P(-1) to high-temperature I(-1), and P(-1) to high-pressure I(-1) , respectively.

  16. High Cost of Stage IV Pressure Ulcers

    PubMed Central

    Brem, Harold; Maggi, Jason; Nierman, David; Rolnitzky, Linda; Bell, David; Rennert, Robert; Golinko, Michael; Yan, Alan; Lyder, Courtney; Vladeck, Bruce

    2010-01-01

    Objective To calculate and analyze the cost of treatment for stage IV pressure ulcers. Methods A retrospective chart analysis of patients with stage IV pressure ulcers was conducted. Hospital records and treatment outcomes of these patients were followed for a maximum of 29 months and analyzed. Costs directly related to the treatment of pressure ulcers and their associated complications were calculated. Results Nineteen patients with stage IV pressure ulcers (11 hospital-acquired and 8 community-acquired) were identified and their charts reviewed. The average hospital treatment cost associated with stage IV pressure ulcers and related complications was $129,248 for hospital-acquired ulcers during one admission, and $124,327 for community-acquired ulcers over an average of 4 admissions. Conclusions The costs incurred from stage IV pressure ulcers are much greater than previously estimated. Halting the progression of early stage pressure ulcers has the potential to eradicate enormous pain and suffering, save thousands of lives, and reduce healthcare expenditures by millions of dollars. PMID:20887840

  17. AIR-BLAST PHENOMENA IN THE HIGH-PRESSURE REGION

    Microsoft Academic Search

    L. M. Swift; D. C. Sachs; A. R. Kriebel

    1960-01-01

    Surface level and aboveground static overpressures, near-surface ; differential pressures, and near-surface total pressures were measured on Burst ; Priscilla. Gages were placed at ground ranges from 450 ft to 4500 ft, with a ; concentration of measurements in the high-pressure region. Blast swttches, which ; measured arrival time only, were placed at several ranges, the closest at 100-ft ;

  18. AN IMPROVED HIGH-PRESSURE VESSEL CONSTRUCTED OF PRESTRESSED CONCRETE

    Microsoft Academic Search

    1963-01-01

    A prestressed-concrete pressure vessel for nuclear reactors or for ; storing gas or liquid it high pressure is patented. The vessel is a monolithic ; concrete cylinder with end slabs. Tensioned cables pass through preformed ; passages in the concrete and are anchored at both ends by anchorages located at ; the ends of the pressure vessel. The passages in

  19. Performance evaluation of PVD coatings for high pressure die casting

    Microsoft Academic Search

    S. Gulizia; M. Z. Jahedi; E. D. Doyle

    2001-01-01

    During high-pressure die-casting (HPDC) of aluminium alloys, there is a tendency for the molten alloy to react with the tool steel die, core pins and inserts. This occurrence within the high pressure die casting (HPDC) industry is referred to as ‘soldering’. It is of concern to high-pressure die casters because of down-time due to the regular removal of the soldered

  20. 46 CFR 153.1104 - Draining of cargo hose: Categories A, B, C, and D.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Draining of cargo hose: Categories A, B, C, and D. 153.1104 Section...Approval of Surveyors and Handling of Categories A, B, C, and D Cargo and Nls Residue...153.1104 Draining of cargo hose: Categories A, B, C, and D. Before a...

  1. 46 CFR 153.1104 - Draining of cargo hose: Categories A, B, C, and D.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Draining of cargo hose: Categories A, B, C, and D. 153.1104 Section...Approval of Surveyors and Handling of Categories A, B, C, and D Cargo and Nls Residue...153.1104 Draining of cargo hose: Categories A, B, C, and D. Before a...

  2. 46 CFR 35.40-17 - Foam hose/monitor stations-T/ALL.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... false Foam hose/monitor stations-T/ALL. 35.40-17 Section 35.40-17 Shipping...OPERATIONS Posting and Marking Requirements-TB/ALL § 35.40-17 Foam hose/monitor stations—T/ALL. (a) At each required foam...

  3. 46 CFR 35.40-17 - Foam hose/monitor stations-T/ALL.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... false Foam hose/monitor stations-T/ALL. 35.40-17 Section 35.40-17 Shipping...OPERATIONS Posting and Marking Requirements-TB/ALL § 35.40-17 Foam hose/monitor stations—T/ALL. (a) At each required foam...

  4. 46 CFR 35.40-17 - Foam hose/monitor stations-T/ALL.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... false Foam hose/monitor stations-T/ALL. 35.40-17 Section 35.40-17 Shipping...OPERATIONS Posting and Marking Requirements-TB/ALL § 35.40-17 Foam hose/monitor stations—T/ALL. (a) At each required foam...

  5. Superconductivity from insulating elements under high pressure

    NASA Astrophysics Data System (ADS)

    Shimizu, Katsuya

    2015-07-01

    The insulating and superconducting states would seem to have very different characteristics. Can any insulator become a superconductor? One proven method, doping an insulating material with carriers, can create itinerant states inside the gap between the conduction and valence bands. Another method is to squeeze the structure by applying pressure. Pressure can expand the bandwidth and also narrow the energy band gap. So the first step to turn an insulator into a superconductor is to make it metallic. Here we review our experimental research and results on superconductivity induced by applying pressure to insulating molecular systems such as elemental molecules.

  6. High-temperature fiber optic pressure sensor

    NASA Technical Reports Server (NTRS)

    Berthold, J. W.

    1984-01-01

    Attention is given to a program to develop fiber optic methods to measure diaphragm deflection. The end application is intended for pressure transducers capable of operating to 540 C. In this paper are reported the results of a laboratory study to characterize the performance of the fiber-optic microbend sensor. The data presented include sensitivity and spring constant. The advantages and limitations of the microbend sensor for static pressure measurement applications are described. A proposed design is presented for a 540 C pressure transducer using the fiber optic microbend sensor.

  7. UPd3 under high pressure: Lattice properties

    NASA Astrophysics Data System (ADS)

    Heathman, S.; Idiri, M.; Rebizant, J.; Boulet, P.; Normile, P. S.; Havela, L.; Sechovský, V.; Le Bihan, T.

    2003-05-01

    The 5f electronic states in UPd3 have a localized 5f2 ground state. Our study examining the behavior of the UPd3 crystal lattice under pressure up to 53 GPa does not reveal any volume anomaly, which could be associated with a delocalization of the 5f electronic states, in the entire pressure range. We thus find a disagreement with calculations based on the self-interaction corrected local spin-density approximation, which predict a transition around the pressure of 25 GPa. A bulk modulus of B0=175(4) GPa with B'0=5.0(4) was determined.

  8. High Pressure (>1 atm) Electrospray Ionization Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Chen, Lee Chuin; Mandal, Mridul Kanti; Hiraoka, Kenzo

    2011-03-01

    High pressure electrospray ionization mass spectrometry has been performed by pressurizing a custom made ion source chamber with compressed air to a pressure higher than the atmospheric pressure. The ion source was coupled to a commercial time-of-flight mass spectrometer using a nozzle-skimmer arrangement. The onset voltage for the electrospray of aqueous solution was found to be independent on the operating pressure. The onset voltage for the corona discharge, however, increased with the rise of pressure following the Paschen's law. Thus, besides having more working gas for the desolvation process, gaseous breakdown could also be avoided by pressurizing the ESI ion source with air to an appropriate level. Stable electrospray ionization has been achieved for the sample solution with high surface tension such as pure water in both positive and negative ion modes. Fragmentation of labile compounds during the ionization process could also be reduced by optimizing the operating pressure of the ion source.

  9. Proposal for high pressure RF cavity test in the MTA

    Microsoft Academic Search

    K. Yonehara

    2010-01-01

    In order to demonstrate the feasibility of high pressure hydrogen gas filled RF (HPRF) cavities for muon ionization cooling, an HPRF cavity must be tested with a high intensity charged beam. When an HPRF cavity is irradiated with an intense beam each incident particle generates about 1000 electrons and ions per cubic centimeter in a high pressure cavity via ionization.

  10. High-pressure Magic Angle Spinning Nuclear Magnetic Resonance

    SciTech Connect

    Hoyt, David W.; Turcu, Romulus VF; Sears, Jesse A.; Rosso, Kevin M.; Burton, Sarah D.; Felmy, Andrew R.; Hu, Jian Z.

    2011-10-01

    A high-pressure magic angle spinning (MAS) NMR capability, consisting of a reusable high-pressure MAS rotor, a high-pressure loading/reaction chamber for in situ sealing and re-opening of the high-pressure MAS rotor, and a MAS probe with a localized RF coil for background signal suppression, is reported. The unusual technical challenges associated with development of a reusable high-pressure MAS rotor are addressed in part by modifying standard ceramics for the rotor sleeve to include micro-groves at the internal surface at both ends of the cylinder. In this way, not only is the advantage of ceramic cylinders for withstanding very high-pressure utilized, but also plastic bushings can be glued tightly in place so that other plastic sealing mechanisms/components and O-rings can be mounted to create the desired high-pressure seal. Using this strategy, sealed internal pressures exceeding 150 bars have been achieved and sustained under ambient external pressure with minimal penetration loss of pressure for 72 hours. As an application example, in situ 13C MAS NMR studies of mineral carbonation reaction intermediates and final products of forsterite (Mg2SiO4) reacted with supercritical CO2 and H2O at 150 bar and 50?C are reported, with relevance to geological sequestration of carbon dioxide.

  11. High-pressure magic angle spinning nuclear magnetic resonance.

    PubMed

    Hoyt, David W; Turcu, Romulus V F; Sears, Jesse A; Rosso, Kevin M; Burton, Sarah D; Felmy, Andrew R; Hu, Jian Zhi

    2011-10-01

    A high-pressure magic angle spinning (MAS) NMR capability, consisting of a reusable high-pressure MAS rotor, a high-pressure rotor loading/reaction chamber for in situ sealing and re-opening of the high-pressure MAS rotor, and a MAS probe with a localized RF coil for background signal suppression, is reported. The unusual technical challenges associated with development of a reusable high-pressure MAS rotor are addressed in part by modifying standard ceramics for the rotor sleeve by abrading the internal surface at both ends of the cylinder. In this way, not only is the advantage of ceramic cylinders for withstanding very high-pressure utilized, but also plastic bushings can be glued tightly in place so that other removable plastic sealing mechanisms/components and O-rings can be mounted to create the desired high-pressure seal. Using this strategy, sealed internal pressures exceeding 150 bars have been achieved and sustained under ambient external pressure with minimal loss of pressure for 72 h. As an application example, in situ(13)C MAS NMR studies of mineral carbonation reaction intermediates and final products of forsterite (Mg(2)SiO(4)) reacted with supercritical CO(2) and H(2)O at 150 bar and 50°C are reported, with relevance to geological sequestration of carbon dioxide. PMID:21862372

  12. High Pressure pH Sensor for Oceanographic Applications

    Microsoft Academic Search

    S. Ben-Yaakov; I. R. Kaplan

    1968-01-01

    A high pressure pH sensor has been developed and tested in the laboratory to a pressure of 150 kg?cm2 and in the ocean to a depth of 270 m. The sensor is composed of specially designed glass membrane and reference electrodes. A pressure equalizing technique is used to prevent pressure gradients across the walls of the electrodes. Seawater buffer was

  13. How Is High Blood Pressure Treated?

    MedlinePLUS

    ... pressure - a hypertension Google+ hangout in honor of World Hypertension Day 04/18/2013 Moderated by American ... live on April 5, 2013 in honor of World Health Day on Sunday, April 7. The NHLBI " ...

  14. How Can High Blood Pressure Be Prevented?

    MedlinePLUS

    ... pressure - a hypertension Google+ hangout in honor of World Hypertension Day 04/18/2013 Moderated by American ... live on April 5, 2013 in honor of World Health Day on Sunday, April 7. The NHLBI " ...

  15. How Is High Blood Pressure Diagnosed?

    MedlinePLUS

    ... pressure - a hypertension Google+ hangout in honor of World Hypertension Day 04/18/2013 Moderated by American ... live on April 5, 2013 in honor of World Health Day on Sunday, April 7. The NHLBI " ...

  16. Notes 11. High pressure floating ring seals 

    E-print Network

    San Andres, Luis

    2009-01-01

    Floating ring seals for compressors: leakage and force coefficients, seal lock up and effect on rotor stability, recommendations to reduce seal cross-coupled effects. Long oil seals as pressure barriers in industrial mixers: leakage and force...

  17. Shell/METC high temperature high pressure filtration program

    SciTech Connect

    Salter, J.A. [Shell Synthetic Fuels Inc., Houston, TX (United States); Rockey, J.M. [Dept. of Energy, Morgantown, WV (United States). Morgantown Energy Technology Center

    1995-12-31

    The purpose of this paper is to present the program objectives and non-proprietary results of the high temperature, high pressure filtration work done under the Shell/METC Cooperative Research and Development Agreement (CRADA) 93-011. The primary purpose of this CRADA was to collect data relevant to the design and operation of dry particulate solids filters employing rigid ceramic (silicon carbide) filter elements in a gasifying environment at conditions of commercial interest; e.g., temperatures up to 1,100 F and system pressures between 300 and 350 psia. Shell provided the ceramic filter elements and evaluated the exposed filter elements. METC installed the filter elements and operated their 10-inch Fluid Bed Gasification and Cleanup facility as required for their Hot Gas Clean-up Test Program. Filter elements were removed from service after approximately 254, 525 and 868 hours of on-line operation. The exposed filter elements were analyzed and compared to an unexposed element with respect to changes in physical property.

  18. Calcium peroxide from ambient to high pressures.

    PubMed

    Nelson, Joseph R; Needs, Richard J; Pickard, Chris J

    2015-03-14

    Structures of calcium peroxide (CaO2) are investigated in the pressure range 0-200 GPa using the ab initio random structure searching (AIRSS) method and density functional theory (DFT) calculations. At 0 GPa, there are several CaO2 structures very close in enthalpy, with the ground-state structure dependent on the choice of exchange-correlation functional. Further stable structures for CaO2 with C2/c, I4/mcm and P21/c symmetries emerge at pressures below 40 GPa. These phases are thermodynamically stable against decomposition into CaO and O2. The stability of CaO2 with respect to decomposition increases with pressure, with peak stability occurring at the CaO B1-B2 phase transition at 65 GPa. Phonon calculations using the quasiharmonic approximation show that CaO2 is a stable oxide of calcium at mantle temperatures and pressures, highlighting a possible role for CaO2 in planetary geochemistry. We sketch the phase diagram for CaO2, and find at least five new stable phases in the pressure-temperature ranges 0 ? P ? 60 GPa, 0 ? T ? 600 K, including two new candidates for the zero-pressure ground state structure. PMID:25673010

  19. High pressure-high temperature phase diagram of ammonia

    NASA Astrophysics Data System (ADS)

    Ninet, S.; Datchi, F.

    2008-04-01

    The high pressure (P)-high temperature (T) phase diagram of solid ammonia has been investigated using diamond anvil cell and resistive heating techniques. The III-IV transition line has been determined up to 20GPa and 500K both on compression and decompression paths. No discontinuity is observed at the expected location for the III-IV-V triple point. The melting line has been determined by visual observations of the fluid-solid equilibrium up to 9GPa and 900K. The experimental data are well fitted by a Simon-Glatzel equation in the covered P-T range. These transition lines and their extrapolations are compared to the reported ab initio calculations.

  20. High pressure/high temperature thermogravimetric apparatus. Final report

    SciTech Connect

    Calo, J.M.; Suuberg, E.M.

    1999-12-01

    The purpose of this instrumentation grant was to acquire a state-of-the-art, high pressure, high temperature thermogravimetric apparatus (HP/HT TGA) system for the study of the interactions between gases and carbonaceous solids for the purpose of solving problems related to coal utilization and applications of carbon materials. The instrument that we identified for this purpose was manufactured by DMT (Deutsche Montan Technologies)--Institute of Cokemaking and Coal Chemistry of Essen, Germany. Particular features of note include: Two reactors: a standard TGA reactor, capable of 1100 C at 100 bar; and a high temperature (HT) reactor, capable of operation at 1600 C and 100 bar; A steam generator capable of generating steam to 100 bar; Flow controllers and gas mixing system for up to three reaction gases, plus a separate circuit for steam, and another for purge gas; and An automated software system for data acquisition and control. The HP/TP DMT-TGA apparatus was purchased in 1996 and installed and commissioned during the summer of 1996. The apparatus was located in Room 128 of the Prince Engineering Building at Brown University. A hydrogen alarm and vent system were added for safety considerations. The system has been interfaced to an Ametek quadruple mass spectrometer (MA 100), pumped by a Varian V250 turbomolecular pump, as provided for in the original proposed. With this capability, a number of gas phase species of interest can be monitored in a near-simultaneous fashion. The MS can be used in a few different modes. During high pressure, steady-state gasification experiments, it is used to sample, measure, and monitor the reactant/product gases. It can also be used to monitor gas phase species during nonisothermal temperature programmed reaction (TPR) or temperature programmed desorption (TPD) experiments.

  1. Synthesis, structure and properties of high pressure and ambient pressure ternary vanadium oxides 

    E-print Network

    Markkula, Mikael

    2013-11-28

    Transition metal oxides have been extensively studied during past decades. The purpose of this research was to synthesize new or little characterised transition metal oxides using high-pressure/high-temperature (HPHT) ...

  2. 46 CFR 27.301 - What are the requirements for fire pumps, fire mains, and fire hoses on towing vessels?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...false What are the requirements for fire pumps, fire mains, and fire hoses on towing...301 What are the requirements for fire pumps, fire mains, and fire hoses on towing...self-priming, power-driven, fixed fire-pump, a fire main, and hoses and...

  3. 46 CFR 27.301 - What are the requirements for fire pumps, fire mains, and fire hoses on towing vessels?

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...false What are the requirements for fire pumps, fire mains, and fire hoses on towing...301 What are the requirements for fire pumps, fire mains, and fire hoses on towing...self-priming, power-driven, fixed fire-pump, a fire main, and hoses and...

  4. 46 CFR 27.301 - What are the requirements for fire pumps, fire mains, and fire hoses on towing vessels?

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...false What are the requirements for fire pumps, fire mains, and fire hoses on towing...301 What are the requirements for fire pumps, fire mains, and fire hoses on towing...self-priming, power-driven, fixed fire-pump, a fire main, and hoses and...

  5. 46 CFR 27.301 - What are the requirements for fire pumps, fire mains, and fire hoses on towing vessels?

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...false What are the requirements for fire pumps, fire mains, and fire hoses on towing...301 What are the requirements for fire pumps, fire mains, and fire hoses on towing...self-priming, power-driven, fixed fire-pump, a fire main, and hoses and...

  6. 46 CFR 27.301 - What are the requirements for fire pumps, fire mains, and fire hoses on towing vessels?

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...false What are the requirements for fire pumps, fire mains, and fire hoses on towing...301 What are the requirements for fire pumps, fire mains, and fire hoses on towing...self-priming, power-driven, fixed fire-pump, a fire main, and hoses and...

  7. EVALUATION OF CERAMIC FILTERS FOR HIGH-TEMPERATURE/HIGH-PRESSURE FINE PARTICULATE CONTROL

    EPA Science Inventory

    High temperature gas turbines used to generate electric power require gas streams virtually free of particulate matter. Gas streams from high temperature, high pressure coal processes, such as low Btu gasification and pressurized fluidized bed combustion, require considerable par...

  8. General formulation for magnetohydrodynamic wave propagation, fire-hose, and mirror instabilities in Harris-type current sheets

    SciTech Connect

    Hau, L.-N. [Institute of Space Science, National Central University, Jhongli, Taiwan (China); Department of Physics, National Central University, Jhongli, Taiwan (China); Lai, Y.-T. [Institute of Space Science, National Central University, Jhongli, Taiwan (China)

    2013-02-15

    Harris-type current sheets with the magnetic field model of B-vector=B{sub x}(z)x-caret+B{sub y}(z)y-caret have many important applications to space, astrophysical, and laboratory plasmas for which the temperature or pressure usually exhibits the gyrotropic form of p{r_reversible}=p{sub Parallel-To }b-caretb-caret+p{sub Up-Tack }(I{r_reversible}-b-caretb-caret). Here, p{sub Parallel-To} and p{sub Up-Tack} are, respectively, to be the pressure component along and perpendicular to the local magnetic field, b-caret=B-vector/B. This study presents the general formulation for magnetohydrodynamic (MHD) wave propagation, fire-hose, and mirror instabilities in general Harris-type current sheets. The wave equations are expressed in terms of the four MHD characteristic speeds of fast, intermediate, slow, and cusp waves, and in the local (k{sub Parallel-To },k{sub Up-Tack },z) coordinates. Here, k{sub Parallel-To} and k{sub Up-Tack} are, respectively, to be the wave vector along and perpendicular to the local magnetic field. The parameter regimes for the existence of discrete and resonant modes are identified, which may become unstable at the local fire-hose and mirror instability thresholds. Numerical solutions for discrete eigenmodes are shown for stable and unstable cases. The results have important implications for the anomalous heating and stability of thin current sheets.

  9. High-temperature fiber optic cubic-zirconia pressure sensor

    NASA Astrophysics Data System (ADS)

    Peng, Wei; Pickrell, Gary R.; Wang, Anbo

    2005-12-01

    There is a critical need for pressure sensors that can operate reliably at high temperatures in many industrial segments such as in the combustion section of gas turbine engines for both transportation and power generation, coal gasifiers, coal fired boilers, etc. Optical-based sensors are particularly attractive for the measurement of a wide variety of physical and chemical parameters in high-temperature and high-pressure industrial environments due to their small size and immunity to electromagnetic interference. A fiber optic pressure sensor utilizing single-crystal cubic zirconia as the sensing element is reported. The pressure response of this sensor has been measured at temperatures up to 1000 °C. Additional experimental results show that cubic zirconia could be used for pressure sensing at temperatures over 1000 °C. This study demonstrates the feasibility of using a novel cubic-zirconia sensor for pressure measurement at high temperatures.

  10. Foil-like manganin gauges for dynamic high pressure measurements

    NASA Astrophysics Data System (ADS)

    Duan, Zhuoping; Liu, Yan; Pi, Aiguo; Huang, Fenglei

    2011-07-01

    Foil-like manganin gauges with a variety of shapes used in different ranges of pressure for the one-dimensional strain mode and axisymmetric strain mode were designed for measuring the detonation pressures of explosives and high shock pressure in materials. In the stress range of 0-53.5 GPa, the pressure-piezoresistance relationships of the manganin gauges were calibrated by the light gas gun and the planar lens of explosive. The piezoresistance coefficients were obtained in different ranges of pressure. To verify the coefficients, the detonation pressure (CJ pressure) of TNT explosive was measured by the manganin gauges, which give similar CJ pressure values to those reported by Zhang et al (2009 Detonation Physics (Beijing: Ordnance Industry Press)) with the maximum relative deviation being less than 3%.

  11. High pressure superconducting radial magnetic bearing

    NASA Technical Reports Server (NTRS)

    Eyssa, Y. M.; Huang, X.

    1990-01-01

    In a conventional radial magnetic bearing, the rotor (soft magnetic material) can only have attraction force from one of the electromagnets in the stator. The stator electromagnets consist of small copper windings with a soft magnetic material iron yoke. The maximum pressure obtainable is about 200 N/sq cm. It is shown that replacing the stator copper winding by a superconducting winding in the above configuration can increase the pressure to about 1000 N/sq cm. It is also shown that replacing the iron in the rotor by a group of superconducting windings in persistent mode and using a group of saddle coils in the stator can produce a pressure in excess of 2000 N/sq cm.

  12. High temperature pressurized high frequency testing rig and test method

    DOEpatents

    De La Cruz, Jose; Lacey, Paul

    2003-04-15

    An apparatus is described which permits the lubricity of fuel compositions at or near temperatures and pressures experienced by compression ignition fuel injector components during operation in a running engine. The apparatus consists of means to apply a measured force between two surfaces and oscillate them at high frequency while wetted with a sample of the fuel composition heated to an operator selected temperature. Provision is made to permit operation at or near the flash point of the fuel compositions. Additionally a method of using the subject apparatus to simulate ASTM Testing Method D6079 is disclosed, said method involving using the disclosed apparatus to contact the faces of prepared workpieces under a measured load, sealing the workface contact point into the disclosed apparatus while immersing said contact point between said workfaces in a lubricating media to be tested, pressurizing and heating the chamber and thereby the fluid and workfaces therewithin, using the disclosed apparatus to impart a differential linear motion between the workpieces at their contact point until a measurable scar is imparted to at least one workpiece workface, and then evaluating the workface scar.

  13. Transient High-Pressure Fuel Injection

    NASA Astrophysics Data System (ADS)

    Jarrahbashi, Dorrin

    Break-up and atomization of liquid fuel jet during transient injection process has a significant effect on the Diesel engine combustion efficiency and pollution. The mechanisms responsible for liquid jet instability and break-up at high pressure, during the transient start-up and steady mass flux periods, has been investigated using Navier-Stokes and level-set computations. Via post-processing, the role of vorticity dynamics is examined and shown to reveal crucial new insights. An unsteady, axisymmetric full-jet case is solved. Then, a less computationally intensive case is studied with a segment of the jet core undergoing temporal instability; agreement with the full-jet calculation is satisfactory justifying the segment analysis for three-dimensional computation. The results for surface-shape development are in agreement with experimental observations and other three-dimensional computations; the initial, axisymmetric waves at the jet surface created by Kelvin-Helmholtz instability distort to cone shapes; next, three-dimensional character develops through an azimuthal instability that leads to the creation of streamwise vorticity, lobe shapes on the cones, and formation of liquid ligaments which extend from lobes on the cones. The cause of this azimuthal instability has been widely described as a Rayleigh-Taylor instability. However, additional and sometimes more important causes are identified here. Counter-rotating, streamwise vortices within and around the ligaments show a relationship in the instability behavior for jets flowing into like-density fluid; thus, density difference cannot explain fully the three-dimensional instability as previously suggested. Furthermore, the formation of ligaments that eventually break into droplets and the formation of streamwise vorticity are caused by the same vortical dynamics. Waviness is identified on the ligaments which should result in droplet formation. The nonlinear development of the shorter azimuthal waves and ligament waves explains the experimental results that droplet sizes are usually smaller than KH wavelengths. The higher the relative velocity and/or the lower the surface tension the shorter are the values of the most unstable wavelengths.

  14. High Pressure Materials Research: Novel Extended Phases of Molecular Triatomics

    Microsoft Academic Search

    Yoo; Choong-Shik

    2006-01-01

    Application of high pressure significantly alters the interatomic distance and thus the nature of intermolecular interaction, chemical bonding, molecular configuration, crystal structure, and stability of solid. With modern advances in high-pressure technologies, it is feasible to achieve a large (often up to a several-fold) compression of lattice, at which condition material can be easily forced into a new physical and

  15. The use of high pressure in basic and materials science

    Microsoft Academic Search

    James S. Schilling

    1998-01-01

    There are at least three important applications of the high pressure technique in basic and materials science: (1) to synthesize novel materials not accessible by other techniques, (2) to transform a given material from one phase to another, and (3) to uncover underlying systematics and critically test theoretical concepts. High pressure studies currently enjoy an increasing popularity which is fueled

  16. X-Ray Fine Structure of Solids Under High Pressure

    Microsoft Academic Search

    Jurgen Freund

    1990-01-01

    This thesis examines the application of X-Ray -Absorption Fine-Structure (XAFS) measurements to problems in high pressure physics. It examines the content of quantitative information of high pressure XAFS spectra and the relation of the XAFS parameters extracted to known physical parameters, especially the bulk modulus and interatomic potential parameters. The materials investigated are copper, amorphous germanium, sodium bromide, potassium bromide

  17. 15. VIEW OF MODULE H, THE HIGH PRESSURE ASSEMBLY AREA. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. VIEW OF MODULE H, THE HIGH PRESSURE ASSEMBLY AREA. PROCESSES IN THIS MODULE OCCURRED UNDER HIGH PRESSURES AND TEMPERATURES. (5/70) - Rocky Flats Plant, Plutonium Manufacturing Facility, North-central section of Plant, just south of Building 776/777, Golden, Jefferson County, CO

  18. Annealed high-density amorphous ice under pressure

    E-print Network

    Loss, Daniel

    ARTICLES Annealed high-density amorphous ice under pressure RICHARD J. NELMES1 *, JOHN S. LOVEDAY1 ices--LDA and HDA--as proxies for the supercooled liquids. But numerous studies over the past decade a previously uncharacterized state of high-density amorphous ice obtained if HDA is annealed at pressures near

  19. Development of a high temperature capacitive pressure transducer

    NASA Technical Reports Server (NTRS)

    Egger, R. L.

    1977-01-01

    High temperature pressure transducers capable of continuous operation while exposed to 650 C were developed and evaluated over a full-scale differential pressure range of + or - 69 kPa. The design of the pressure transducers was based on the use of a diaphragm to respond to pressure, variable capacitive elements arranged to operate as a differential capacitor to measure diaphragm response and on the use of fused silica for the diaphragm and its supporting assembly. The uncertainty associated with measuring + or - 69 kPa pressures between 20C and 650C was less than + or - 6%.

  20. A high-temperature wideband pressure transducer

    Microsoft Academic Search

    A. J. Zuckerwar

    1977-01-01

    A condenser microphone AM carrier system, which has been developed to measure pressure fluctuations at elevated temperatures, consists of the following components: a condenser microphone designed for operation at elevated temperatures; existing carrier electronics developed under two previous research grants but adapted to meet present requirements; a 6 m cable operating as a half-wavelength transmission line between the microphone and

  1. MATHEMATICAL MODELING OF ULTRA HIGH PRESSURE

    Microsoft Academic Search

    S. Kunaporn; M. Ramulu

    Waterjet peening is a recent promising method in surface treatment. It has potential to induce compressive residual stresses that benefit the fatigue life of materials similar to the conventional shot peening process. However, there are no analytical models that incorporate process parameters, i.e. supply pressure, jet exposure time, and nozzle traverse rate etc., to allow predicting the optimized peening process.

  2. [Genesis study of omphacite at high pressure and high temperature].

    PubMed

    Xiao, Ben-Fu; Yi, Li; Wang, Duo-Jun; Xie, Chao; Tang, Xue-Wu; Liu, Lei; Cui, Yue-Ju

    2013-11-01

    The melting and recrystallizing experiments of alkali basalt powder and mixture of pure oxides mixed as stoichiometry were performed at 3 GPa and 1 200 degrees C. Electronic microprobe analysis and Raman spectra showed that the recrystallized products were omphacites, the FWHM (full width at half maximum) of the Raman peak was narrow and its shape was sharp, which is attributed to the stable Si-O tetrahedral structure and the high degree of order in omphacite. Based on the results of previous studies, the influencing factors of omphacite genesis and its primary magma were discussed. The results showed that the formation of omphacite could be affected by many factors, such as the composition of parent rocks, the concentration of fluid in the system and the conditions of pressure and temperature. This result could support some experimental evidences on the genesis studies of omphacite and eclogite. PMID:24555367

  3. High-Temperature High-Pressure Bitumen Sand Laboratory Measurements

    NASA Astrophysics Data System (ADS)

    Wolf, K.; Vanorio, T.

    2008-12-01

    The recent increase in the development and production of heavy-oil reservoirs has brought the need for a reliable, quantitative, reservoir characterization and monitoring methodology to the forefront. In order for this task to be successfully completed a dependable and robust rock physics model or transform needs to be established for these types of reservoirs. In order to calibrate this type of model there is a need for a large, reliable laboratory measured dataset of reservoir properties under various environmental conditions. However, due to the soft nature of these reservoirs, and the variation of properties with temperature, pressure, etc., this is a particularly challenging task. In order to fill this knowledge gap we have performed thorough modeling in order to design an optimum system to measure the acoustic and elastic properties of heavy-oil saturated sands over a temperature range of 0-200oC, and pressures of 0-35 MPa. The modeling effort focused on designing transducers that are able to produce high-amplitude broad-band pulse transmission signals through heavy-oil sand samples over a large temperature range. This includes 1) using a non-traditional end cap material, as well as piezoelectric crystals with high operating temperatures and 2) a priori testing of the performance of the transducers under varying conditions by modeling the signal output. This has been achieved by using the Krimholtz, Leedom and Matthaei (KLM) equivalent circuit model to ensure that the design of the transducer is optimal. While there are many challenges faced when creating a set of rock physics measurements in order to calibrate rock physics models for bitumen sands, we feel that our approach addresses many of the major obstacles. With our specially designed equipment and novel approaches to the measurement of bitumen sand properties we feel that we have made significant strides towards providing a robust dataset from which many rock physics models and principles related to bitumen and heavy oil reservoirs can be built.

  4. Experimental investigation on pressurization performance of cryogenic tank during high-temperature helium pressurization process

    NASA Astrophysics Data System (ADS)

    Lei, Wang; Yanzhong, Li; Yonghua, Jin; Yuan, Ma

    2015-03-01

    Sufficient knowledge of thermal performance and pressurization behaviors in cryogenic tanks during rocket launching period is of importance to the design and optimization of a pressurization system. In this paper, ground experiments with liquid oxygen (LO2) as the cryogenic propellant, high-temperature helium exceeding 600 K as the pressurant gas, and radial diffuser and anti-cone diffuser respectively at the tank inlet were performed. The pressurant gas requirements, axial and radial temperature distributions, and energy distributions inside the propellant tank were obtained and analyzed to evaluate the comprehensive performance of the pressurization system. It was found that the pressurization system with high-temperature helium as the pressurant gas could work well that the tank pressure was controlled within a specified range and a stable discharging liquid rate was achieved. For the radial diffuser case, the injected gas had a direct impact on the tank inner wall. The severe gas-wall heat transfer resulted in about 59% of the total input energy absorbed by the tank wall. For the pressurization case with anti-cone diffuser, the direct impact of high-temperature gas flowing toward the liquid surface resulted in a greater deal of energy transferred to the liquid propellant, and the percentage even reached up to 38%. Moreover, both of the two cases showed that the proportion of energy left in ullage to the total input energy was quite small, and the percentage was only about 22-24%. This may indicate that a more efficient diffuser should be developed to improve the pressurization effect. Generally, the present experimental results are beneficial to the design and optimization of the pressurization system with high-temperature gas supplying the pressurization effect.

  5. Structure and stability of hydrous minerals at high pressure

    NASA Technical Reports Server (NTRS)

    Duffy, T. S.; Fei, Y.; Meade, C.; Hemley, R. J.; Mao, H. K.

    1994-01-01

    The presence of even small amounts of hydrogen in the Earth's deep interior may have profound effects on mantle melting, rheology, and electrical conductivity. The recent discovery of a large class of high-pressure H-bearing silicates further underscores the potentially important role for hydrous minerals in the Earth's mantle. Hydrogen may also be a significant component of the Earth's core, as has been recently documented by studies of iron hydride at high pressure. In this study, we explore the role of H in crystal structures at high pressure through detailed Raman spectroscopic and x ray diffraction studies of hydrous minerals compressed in diamond anvil cells. Brucite, Mg(OH)2, has a simple structure and serves as an analogue for the more complex hydrous silicates. Over the past five years, this material has been studied at high pressure using shock-compression, powder x ray diffraction, infrared spectroscopy, Raman spectroscopy, and neutron diffraction. In addition, we have recently carried out single-crystal synchrotron x-ray diffraction on Mg(OH)2 and Raman spectroscopy on Mg(OD)2 at elevated pressure. From all these studies, an interesting picture of the crystal chemical behavior of this material at high pressure is beginning to emerge. Some of the primary conclusions are as follows: First, hydrogen bonding is enhanced by the application of pressure. Second, layered minerals which are elastically anisotropic at low pressure may not be so at high pressure. Furthermore, the brucite data place constraints on the effect of hydrogen on seismic velocities and density at very high pressure. Third, the stability of hydrous minerals may be enhanced at high P by subtle structural rearrangements that are difficult to detect using traditional probes and require detailed spectroscopic analyses. Finally, brucite appears to be unique in that it undergoes pressure-induced disordering that is confined solely to the H-containing layers of the structure.

  6. Amorphous diamond: A high-pressure superhard carbon allotrope

    SciTech Connect

    Lin, Yu [Stanford Univ., Stanford, CA (United States); Zhang, Li [Geophysical Lab., Carnegie Inst. of Washington, Washington, DC (United States); Mao, Ho Kwang [Geophysical Lab., Carnegie Inst. of Washington, Washington, DC (United States); Chow, Paul [High Pressure Collaborative Access Team (HPCAT), Geophysical Lab., Carnegie Inst. of Washington, Washington, DC (United States); Xiao, Yuming [High Pressure Collaborative Access Team (HPCAT), Geophysical Lab., Carnegie Inst. of Washington, Washington, DC (United States); Baldini, Maria [High Pressure Synergetic Consortium, Geophysical Lab., Carnegie Inst. of Washington, Washington, DC (United States); Shu, Jinfu [Geophysical Lab., Carnegie Inst. of Washington, Washington, DC (United States); Mao, Wendy L. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States)

    2011-10-01

    Compressing glassy carbon above 40 GPa, we have observed a new carbon allotrope with a fully sp³-bonded amorphous structure and diamondlike strength. Synchrotron x-ray Raman spectroscopy revealed a continuous pressure-induced sp²-to-sp³ bonding change, while x-ray diffraction confirmed the perseverance of noncrystallinity. The transition was reversible upon releasing pressure. Used as an indenter, the glassy carbon ball demonstrated exceptional strength by reaching 130 GPa with a confining pressure of 60 GPa. Such an extremely large stress difference of >70??GPa has never been observed in any material besides diamond, indicating the high hardness of this high-pressure carbon allotrope.

  7. Elastic constants of solids at high pressures

    SciTech Connect

    Krasil'nikov, O. M., E-mail: omkras@mail.ru; Vekilov, Yu. Kh.; Mosyagin, I. Yu. [National Research Technological University MISiS (Russian Federation)

    2012-08-15

    The isothermal and adiabatic nth-order (n {>=} 2) elastic constants of a loaded crystal are defined. These constants fully determine the behavior of solids at an arbitrary load and are controlled by both an interatomic interaction and an applied load. Expressions that relate these constants (of the second, third, and fourth order) to Brugger elastic constants of the corresponding order, which are only determined by an inter-atomic interaction, are found for cubic symmetry crystals under hydrostatic pressure. These expressions are used to calculate the equation of state and the second- and third-order elastic constants of bcc tantalum at T = 0 K over a wide pressure range (0-600 GPa) using an electron density functional method. The results of calculating the equation of state and the second-order elastic constants agree with available experimental data and the calculation results obtained in other works.

  8. Report of the National High Blood Pressure Education Program Working Group on High Blood Pressure in Pregnancy

    Microsoft Academic Search

    2000-01-01

    This report updates the 1990 “National High Blood Pressure Education Program Working Group Report on High Blood Pressure in Pregnancy” and focuses on classification, pathophysiologic features, and management of the hypertensive disorders of pregnancy. Through a combination of evidence-based medicine and consensus this report updates contemporary approaches to hypertension control during pregnancy by expanding on recommendations made in “The Sixth

  9. New silver contact pastes from high pressure sintering to low pressure sintering

    Microsoft Academic Search

    W. Schmitt; W. C. Heraeus

    2010-01-01

    Heraeus has developed a novel concept for silver sinter pastes. The new concept uses micro scale silver particles combined with sinter additives. The novel pastes have high sinter activity and a can be used in pressure free or less pressure bonding processes. The physical properties like shear strength at temperature above 200°C, electrical and thermal conductivity are outstanding compared to

  10. High-pressure vibrational properties of polyethylene

    Microsoft Academic Search

    Luca Fontana; Mario Santoro; Roberto Bini; Diep Q. Vinh; Sandro Scandolo

    2010-01-01

    The pressure evolution of the vibrational spectrum of polyethylene was investigated up to 50 GPa along different isotherms by Fourier-transform infrared and Raman spectroscopy and at 0 K by density-functional theory calculations. The infrared data allow for the detection of the orthorhombic Pnam to monoclinic P21\\/m phase transition which is characterized by a strong hysteresis both on compression and decompression

  11. Phosphate corrosion in high-pressure boilers

    Microsoft Academic Search

    H. M. Herro; A. Banweg

    1995-01-01

    As operating pressures have increased, the frequency of corrosion-related failures in phosphate-treated boilers has also increased. Congruent phosphate control was derived to prevent the formation of free caustic by feeding orthophosphates to maintain a boiler water sodium-to-phosphate ratio at which theory surmised free caustic could not form. Unfortunately, conventional congruent control did not take into account the interaction of phosphate

  12. Effect of high pressure on hydrocarbon-degrading bacteria.

    PubMed

    Schedler, Martina; Hiessl, Robert; Valladares Juárez, Ana Gabriela; Gust, Giselher; Müller, Rudolf

    2014-01-01

    The blowout of the Deepwater Horizon in the Gulf of Mexico in 2010 occurred at a depth of 1500 m, corresponding to a hydrostatic pressure of 15 MPa. Up to now, knowledge about the impact of high pressure on oil-degrading bacteria has been scarce. To investigate how the biodegradation of crude oil and its components is influenced by high pressures, like those in deep-sea environments, hydrocarbon degradation and growth of two model strains were studied in high-pressure reactors. The alkane-degrading strain Rhodococcus qingshengii TUHH-12 grew well on n-hexadecane at 15 MPa at a rate of 0.16 h(-1), although slightly slower than at ambient pressure (0.36 h(-1)). In contrast, the growth of the aromatic hydrocarbon degrading strain Sphingobium yanoikuyae B1 was highly affected by elevated pressures. Pressures of up to 8.8 MPa had little effect on growth of this strain. However, above this pressure growth decreased and at 12 MPa or more no more growth was observed. Nevertheless, S. yanoikuyae continued to convert naphthalene at pressure >12 MPa, although at a lower rate than at 0.1 MPa. This suggests that certain metabolic functions of this bacterium were inhibited by pressure to a greater extent than the enzymes responsible for naphthalene degradation. These results show that high pressure has a strong influence on the biodegradation of crude oil components and that, contrary to previous assumptions, the role of pressure cannot be discounted when estimating the biodegradation and ultimate fate of deep-sea oil releases such as the Deepwater Horizon event. PMID:25401077

  13. Effect of high pressure on hydrocarbon-degrading bacteria

    PubMed Central

    2014-01-01

    The blowout of the Deepwater Horizon in the Gulf of Mexico in 2010 occurred at a depth of 1500 m, corresponding to a hydrostatic pressure of 15 MPa. Up to now, knowledge about the impact of high pressure on oil-degrading bacteria has been scarce. To investigate how the biodegradation of crude oil and its components is influenced by high pressures, like those in deep-sea environments, hydrocarbon degradation and growth of two model strains were studied in high-pressure reactors. The alkane-degrading strain Rhodococcus qingshengii TUHH-12 grew well on n-hexadecane at 15 MPa at a rate of 0.16 h?1, although slightly slower than at ambient pressure (0.36 h?1). In contrast, the growth of the aromatic hydrocarbon degrading strain Sphingobium yanoikuyae B1 was highly affected by elevated pressures. Pressures of up to 8.8 MPa had little effect on growth of this strain. However, above this pressure growth decreased and at 12 MPa or more no more growth was observed. Nevertheless, S. yanoikuyae continued to convert naphthalene at pressure >12 MPa, although at a lower rate than at 0.1 MPa. This suggests that certain metabolic functions of this bacterium were inhibited by pressure to a greater extent than the enzymes responsible for naphthalene degradation. These results show that high pressure has a strong influence on the biodegradation of crude oil components and that, contrary to previous assumptions, the role of pressure cannot be discounted when estimating the biodegradation and ultimate fate of deep-sea oil releases such as the Deepwater Horizon event. PMID:25401077

  14. High-pressure applications in medicine and pharmacology

    NASA Astrophysics Data System (ADS)

    Silva, Jerson L.; Foguel, Debora; Suarez, Marisa; Gomes, Andre M. O.; Oliveira, Andréa C.

    2004-04-01

    High pressure has emerged as an important tool to tackle several problems in medicine and biotechnology. Misfolded proteins, aggregates and amyloids have been studied, which point toward the understanding of the protein misfolding diseases. High hydrostatic pressure (HHP) has also been used to dissociate non-amyloid aggregates and inclusion bodies. The diverse range of diseases that result from protein misfolding has made this theme an important research focus for pharmaceutical and biotech companies. The use of high pressure promises to contribute to identifying the mechanisms behind these defects and creating therapies against these diseases. High pressure has also been used to study viruses and other infectious agents for the purpose of sterilization and in the development of vaccines. Using pressure, we have detected the presence of a ribonucleoprotein intermediate, where the coat protein is partially unfolded but bound to RNA. These intermediates are potential targets for antiviral compounds. The ability of pressure to inactivate viruses, prions and bacteria has been evaluated with a view toward the applications of vaccine development and virus sterilization. Recent studies demonstrate that pressure causes virus inactivation while preserving the immunogenic properties. There is increasing evidence that a high-pressure cycle traps a virus in the 'fusion intermediate state', not infectious but highly immunogenic.

  15. The effect of high pressure on nitrogen compounds of milk

    NASA Astrophysics Data System (ADS)

    Kielczewska, Katarzyna; Czerniewicz, Maria; Michalak, Joanna; Brandt, Waldemar

    2004-04-01

    The effect of pressurization at different pressures (from 200 to 1000 MPa, at 200 MPa intervals, tconst. = 15 min) and periods of time (from 15 to 35 min, at 10 min intervals, pconst. = 800 MPa) on the changes of proteins and nitrogen compounds of skimmed milk was studied. The pressurization caused an increase in the amount of soluble casein and denaturation of whey proteins. The level of nonprotein nitrogen compounds and proteoso-peptone nitrogen compounds increased as a result of the high-pressure treatment. These changes increased with an increase in pressure and exposure time. High-pressure treatment considerably affected the changes in the conformation of milk proteins, which was reflected in the changes in the content of proteins sedimenting and an increase in their degree of hydration.

  16. High-power, high-pressure IR Ar - Xe lasers

    SciTech Connect

    Kholin, I V [P.N. Lebedev Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2003-02-28

    Investigations of high-pressure lasers on Ar - Xe mixtures pumped by electron beams and electroionisation discharges are reviewed. A new method of pumping laser transitions by an electroionisation discharge is proposed. The method uses the excited states of Xe atoms as the ground laser level. An electroionisation laser on the IR transitions of a Xe atom with a volume of the active region of 10 L and a pulse duration of 5 {mu}s is developed on this basis. Its specific (up to 8 J L{sup -1}) and absolute (up to 80 J) energy outputs exceed those of electric-discharge noble-gas lasers by more than one and two orders of magnitude, respectively. It is shown that the efficiency of conversion of the electric energy deposited in the discharge into laser radiation can be as high as 5%. The laser beam divergence obtained at output energies close to the maximum one is {approx}3 x 10{sup -5} rad. It is shown in principle that a repetitively pulsed Xe laser emitting at 1.73 {mu}m with a specific energy output of 0.5 - 1.0 kW L{sup -1} and an efficiency of 2.0% - 3.2% can be created. (special issue devoted to the 80th anniversary of academician n g basov's birth)

  17. New Phases of C60 Synthesized at High Pressure

    Microsoft Academic Search

    Y. Iwasa; T. Arima; R. M. Fleming; T. Siegrist; O. Zhou; R. C. Haddon; L. J. Rothberg; K. B. Lyons; H. L. Carter Jr.; A. F. Hebard; R. Tycko; G. Dabbagh; J. J. Krajewski; G. A. Thomas; T. Yagi

    1994-01-01

    The fullerene C60 can be converted into two different structures by high pressure and temperature. They are metastable and revert to pristine C60 on reheating to 300^circC at ambient pressure. For synthesis temperatures between 300^circ and 400^circC and pressures of 5 gigapascals, a nominal face-centered-cubic structure is produced with a lattice parameter a_o = 13.6 angstroms. When treated at 500^circ

  18. High-pressure viscosity and density of n -alkanes

    Microsoft Academic Search

    E. Kiran; Y. L. Sen

    1992-01-01

    High-pressure viscosities and densities of n-butane, n-pentane, n-hexane, and n-octane have been measured with a specially designed falling cylinder viscometer. Data cover the pressure range from 10 to 70 MPa at temperatures from 310 to 450 K. When the viscosity is plotted as a function of density, the data at all temperatures and pressures are shown to reduce to a

  19. Cavitation-Induced Reactions in High-Pressure Carbon Dioxide

    Microsoft Academic Search

    M. W. A. Kuijpers; D. van Eck; M. F. Kemmere; J. T. F. Keurentjes

    2002-01-01

    The feasibility of ultrasound-induced in situ radical formation in liquid carbon dioxide was demonstrated. The required threshold pressure for cavitation could be exceeded at a relatively low acoustic intensity, as the high vapor pressure of CO2 counteracts the hydrostatic pressure. With the use of a dynamic bubble model, the formation of hot spots upon bubble collapse was predicted. Cavitation-induced radical

  20. High pressure X-ray diffraction study of URh3

    NASA Astrophysics Data System (ADS)

    Shukla, B.; Chandra Shekar, N. V.; Sanjay Kumar, N. R.; Sahu, P. Ch

    2012-06-01

    High pressure x-ray diffraction studies on URh3 have been carried out up to 31 GPa using a diamond anvil cell. URh3 which exists in AuCu3 type structure at ambient pressure remains stable up to the pressure studied. The Birch-Murnaghan equation of state fit for the P-V data yields the bulk modulus to be 193 GPa.

  1. High pressure synthesis gas conversion. Task 2: Determination of maximum operating pressure

    SciTech Connect

    Not Available

    1993-05-01

    The purpose of this research project was to build and test a high pressure fermentation system for the production of ethanol from synthesis gas. The fermenters, pumps, controls, and analytical system were procured or fabricated and assembled in our laboratory. This system was then used to determine the effects of high pressure on growth and ethanol production by C. ljungdahlil. The limits of cell concentration and mass transport relationships were found in CSTR and immobilized cell reactors (ICR). The minimum retention times and reactor volumes were found for ethanol production in these reactors. The purpose of this report was to present the results of high pressure experiments aimed at determining the maximum operating pressure of C. ljungdahlil. Preliminary experiments carried out in approaching the pressure maximum are presented, as well as experimental results at the maximum pressure of 150 psig. This latter pressure was the maximum operating pressure when using the defined medium of Phillips et al., and is expected to change if alternative media are employed.

  2. Automated high pressure cell for pressure jump x-ray diffraction.

    PubMed

    Brooks, Nicholas J; Gauthe, Beatrice L L E; Terrill, Nick J; Rogers, Sarah E; Templer, Richard H; Ces, Oscar; Seddon, John M

    2010-06-01

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems. PMID:20590253

  3. High-temperature and pressure Raman spectroscopy of diamond

    Microsoft Academic Search

    En-Ping Huang; Eugene Huang; Shu-Cheng Yu; Yen-Hua Chen; Jiann-Shing Lee; Jiann-Neng Fang

    2010-01-01

    This study presents the results of the first use of the moissanite anvil cell (MAC) for the in-situ high-temperature and pressure Raman spectroscopy measurement of diamond. It is observed that the T2g vibrational mode of diamond shifts toward low frequency with increasing temperature; on the other hand, the vibration band shifts toward high frequency with increasing pressure. In the high-temperature

  4. Continuum radiation in a high pressure argon–mercury lamp

    Microsoft Academic Search

    K T A L Burm

    2004-01-01

    In typical high pressure high intensity discharge lamps about 60% of the deposited power is released in non-useful channels, non-radiative heat transfer from the hot arc core, ultraviolet radiation and infrared radiation, of which the last is the dominant one.To reduce the amount of infrared radiation emitted in high pressure argon–mercury lamps the sources of continuum radiation are identified, quantified

  5. Laser welding in a high pressure gas environment

    Microsoft Academic Search

    G. J. Shannon; J. Watson; W. F. Deans

    1995-01-01

    A study was undertaken to investigate the effect of a high pressure gas environment on the laser welding mechanism. This was specifically related to high power CO2 lasers in the power range between 1.2 and 5 kW. A small high pressure chamber rated up to 150 bar was utilized for the trials. Successful laser welding was completed up to a

  6. IMC hydrides with high hydrogen dissociation pressure

    Microsoft Academic Search

    T. A. Zotov; R. B. Sivov; E. A. Movlaev; S. V. Mitrokhin; V. N. Verbetsky

    2011-01-01

    Hydrogen sorption properties of a large variety of solid solutions on the base of ZrCr2 and TiFe2 intermetallic compounds are studied at pressures up to 300MPa. Partial substitution of Cr by small amounts of Me=Al, Mn, Mo, Ni and B does not significantly change the H\\/M ratio of hydrides of the Ti(Cr1?xMex)2?a alloys with 0

  7. High-current cathodes of high-pressure plasmatrons

    NASA Astrophysics Data System (ADS)

    Vertiprakhov, A. I.; Zakharkin, R. Ia.; Kucherov, Ia. R.; Povaliaev, O. A.; Pustogarov, A. V.

    1988-06-01

    The performance of rod-shaped tungsten cathodes in helium and nitrogen atmospheres is investigated experimentally. In a nitrogen atmosphere at pressures above 0.5 MPa, the rod cathodes fail at currents higher than 500 A. In helium, similar cathodes operate stably at a current of 1.5 kA and pressures up to 2 MPa. Zirconium cathodes with a conical insert operate stably at currents up to 2 kA and pressures up to 2 MPa.

  8. Theoretical Thermodynamics of Mixtures at High Pressures

    NASA Technical Reports Server (NTRS)

    Hubbard, W. B.

    1985-01-01

    The development of an understanding of the chemistry of mixtures of metallic hydrogen and abundant, higher-z material such as oxygen, carbon, etc., is important for understanding of fundamental processes of energy release, differentiation, and development of atmospheric abundances in the Jovian planets. It provides a significant theoretical base for the interpretation of atmospheric elemental abundances to be provided by atmospheric entry probes in coming years. Significant differences are found when non-perturbative approaches such as Thomas-Fermi-Dirac (TFD) theory are used. Mapping of the phase diagrams of such binary mixtures in the pressure range from approx. 10 Mbar to approx. 1000 Mbar, using results from three-dimensional TFD calculations is undertaken. Derivation of a general and flexible thermodynamic model for such binary mixtures in the relevant pressure range was facilitated by the following breakthrough: there exists an accurate nd fairly simple thermodynamic representation of a liquid two-component plasma (TCP) in which the Helmholtz free energy is represented as a suitable linear combination of terms dependent only on density and terms which depend only on the ion coupling parameter. It is found that the crystal energies of mixtures of H-He, H-C, and H-O can be satisfactorily reproduced by the same type of model, except that an effective, density-dependent ionic charge must be used in place of the actual total ionic charge.

  9. 49 CFR 393.45 - Brake tubing and hoses; hose assemblies and end fittings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...contacting the vehicle's exhaust system or any other source of high temperatures...connections for air, vacuum, or hydraulic braking systems shall be installed so as to...affect the performance of the brake system. [70 FR 48050, Aug....

  10. High pressure sample cell for total internal reflection fluorescence spectroscopy at pressures up to 2500 bar

    NASA Astrophysics Data System (ADS)

    Koo, Juny; Czeslik, Claus

    2012-08-01

    Total internal reflection fluorescence (TIRF) spectroscopy is a surface sensitive technique that is widely used to characterize the structure and dynamics of molecules at planar liquid-solid interfaces. In particular, biomolecular systems, such as protein adsorbates and lipid membranes can easily be studied by TIRF spectroscopy. Applying pressure to molecular systems offers access to all kinds of volume changes occurring during assembly of molecules, phase transitions, and chemical reactions. So far, most of these volume changes have been characterized in bulk solution, only. Here, we describe the design and performance of a high pressure sample cell that allows for TIRF spectroscopy under high pressures up to 2500 bar (2.5 × 108 Pa), in order to expand the understanding of volume effects from the bulk phase to liquid-solid interfaces. The new sample cell is based on a cylindrical body made of Nimonic 90 alloy and incorporates a pressure transmitting sample cuvette. This cuvette is composed of a fused silica prism and a flexible rubber gasket. It contains the sample solution and ensures a complete separation of the sample from the liquid pressure medium. The sample solution is in contact with the inner wall of the prism forming the interface under study, where fluorescent molecules are immobilized. In this way, the new high pressure TIRF sample cell is very useful for studying any biomolecular layer that can be deposited at a planar water-silica interface. As examples, high pressure TIRF data of adsorbed lysozyme and two phospholipid membranes are presented.

  11. High pressure testing of see-through labyrinth seals 

    E-print Network

    Picardo, Arthur Michael

    2003-01-01

    Detailed results are presented for teeth-on-stator labyrinth seals tested under high pressure of 70 bar-a (1015 psi-a) and 52 bar-a (754 psi-a) in the centered position. The seals were tested at pressure ratios of 0.52, 0.36 and 0.16, speeds of 10...

  12. Controls for Offshore High Pressure Corrosive\\\\ Gas Wells

    Microsoft Academic Search

    Robert Bailliet

    1982-01-01

    In September 1981, Shell Oil Company began production from its first high-pressure corrosive gas well in the Gulf of Mexico. The extreme pressures and corrosive nature of the gas required the installation of a 20,000 psi low alloy steel christmas tree, equipped with 12 hydraulically operated safety and control valves. This study describes the instrumentation and control system developed to

  13. Neutron scattering at high pressure D. B. McWhan

    E-print Network

    Paris-Sud XI, Université de

    715 Neutron scattering at high pressure D. B. McWhan Room 1D-234, Murray Hill, New Jersey 07974, U scattering at steady-state and pulsed sources are reviewed. The pressure cells available at most neutron 10 GPa have been made. For elastic scattering, a comparison is made between neutron scattering and X

  14. Rotordynamic stability problems and solutions in high pressure turbocompressors

    NASA Technical Reports Server (NTRS)

    Schmied, J.

    1989-01-01

    The stability of a high pressure compressor is investigated with special regard to the self-exciting effects in oil seals and labyrinths. It is shown how to stabilize a rotor in spite of these effects and even increase its stability with increasing pressure.

  15. High-sampling-rate pressure transducer has in situ calibration

    NASA Technical Reports Server (NTRS)

    Gross, C.

    1979-01-01

    High-data-rate pressure sensor module can be calibrated after it is attached to an experimental setup. Electrically multiplexed sensor is designed for use in wind-tunnels and other applications requiring accurate measurement of many pressures in a short period of time.

  16. CRYSTAL STRUCTURES OF TITANIUM, ZIRCONIUM, AND HAFNIUM AT HIGH PRESSURES

    Microsoft Academic Search

    J. C. Jamieson

    1963-01-01

    At high pressures, as determined by x-ray analysis, titanium and ; zirconium metal have a distorted, bodycentered-cubic structure. This phase ; persists on pressure release. The normal hexagonal close-packed structures are ; recovered when the metals are heated. An electronic shift must occur in the ; transition. Hafnium metal showed no such transition. (auth);

  17. Detail view of unit 43 with high pressure stage compressor ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view of unit 43 with high pressure stage compressor in left foreground and low pressure stage compressor in right background. - Burnsville Natural Gas Pumping Station, Saratoga Avenue between Little Kanawha River & C&O Railroad line, Burnsville, Braxton County, WV

  18. Elastohydrodynamic Lubrication at High Pressures. II. Non-Newtonian Behaviour

    Microsoft Academic Search

    W. Hirst; A. J. Moore

    1979-01-01

    An experimental study has been made of the elastohydrodynamic behaviour of a range of fluids, including some of widely different pressure coefficient of viscosity. It is shown that the complex pattern of elastohydrodynamic behaviour observed at high pressure is due predominantly to the interplay between two non-Newtonian effects. The first is viscoelasticity. This has the effect that, at small degrees

  19. High Pressure Burn Rate Measurements on an Ammonium Perchlorate Propellant

    Microsoft Academic Search

    E A Glascoe; N Tan

    2010-01-01

    High pressure deflagration rate measurements of a unique ammonium perchlorate (AP) based propellant are required to design the base burn motor for a Raytheon weapon system. The results of these deflagration rate measurements will be key in assessing safety and performance of the system. In particular, the system may experience transient pressures on the order of 100's of MPa (10's

  20. Effect of osmolytes on pressure-induced unfolding of proteins: a high-pressure SAXS study.

    PubMed

    Krywka, Christina; Sternemann, Christian; Paulus, Michael; Tolan, Metin; Royer, Catherine; Winter, Roland

    2008-12-22

    Herein, we explore the effect of different types of osmolytes on the high-pressure stability and tertiary structure of a well-characterized monomeric protein, staphylococcal nuclease (SNase). Changes in the denaturation pressure and the radius of gyration are obtained in the presence of different concentrations of trimethylamine N-oxide (TMAO), glycerol and urea. To reveal structural changes in the protein upon compression at various osmolyte conditions, small-angle X-ray scattering (SAXS) experiments were carried out. To this end, a new high-pressure cell suitable for high-precision SAXS studies at synchrotron sources was built, which allows one to carry out scattering experiments up to maximum pressures of about 7 kbar. Our data clearly indicate that the osmolytes that stabilize proteins against temperature-induced unfolding drastically increase their pressure stability and that the elliptically shaped curve of the pressure-temperature-stability diagram of proteins is shifted to higher temperatures and pressures with increasing osmolyte concentration. A drastic stabilization is observed for the osmolyte TMAO, which exhibits not only a significant stabilization against temperature-induced unfolding, but also a particularly strong stabilization of the protein against pressure. In fact, such findings are in accordance with in vivo studies (for example P. J. Yancey, J. Exp. Biol. 2005, 208, 2819-2830), where unusually high TMAO concentrations in some deep-sea animals were found. Conversely, chaotropic agents such as urea have a strong destabilizing effect on both the temperature and pressure stability of the protein. Our data also indicate that sufficiently high TMAO concentrations might be able to largely offset the destabilizing effect of urea. The different scenarios observed are discussed in the context of recent experimental and theoretical studies. PMID:18924198

  1. Birdmuscles under hydrostatic high-pressure\\/temperature combinations

    Microsoft Academic Search

    F. Fernández-Martín

    2007-01-01

    Breast muscles from three different birds\\u000a were subjected to hydrostatic high-pressure (400 MPa)\\/temperature (10–75°C)\\u000a combinations, and the denaturation-induced effects on the pressurized proteins\\u000a monitored by DSC. Comparisons with parallel results from heating-alone processes\\u000a were established. Actin was the most labile moiety to pressurization and myosin\\u000a together with sarcoplasmic proteins were next in observing pressure-induced\\u000a denaturation at low temperatures. Some myosin

  2. Rotational viscometer for high-pressure high-temperature fluids

    DOEpatents

    Carr, Kenneth R. (Knoxville, TN)

    1985-01-01

    The invention is a novel rotational viscometer which is well adapted for use with fluids at high temperatures and/or pressures. In one embodiment, the viscometer includes a substantially non-magnetic tube having a closed end and having an open end in communication with a fluid whose viscosity is to be determined. An annular drive magnet is mounted for rotation about the tube. The tube encompasses and supports a rotatable shaft assembly which carries a rotor, or bob, for insertion in the fluid. Affixed to the shaft are (a) a second magnet which is magnetically coupled to the drive magnet and (b) a third magnet. In a typical operation, the drive magnet is rotated to turn the shaft assembly while the shaft rotor is immersed in the fluid. The viscous drag on the rotor causes the shaft assembly to lag the rotation of the drive magnet by an amount which is a function of the amount of viscous drag. A first magnetic pickup generates a waveform whose phase is a function of the angular position of the drive magnet. A second magnetic pickup generates a waveform whose phase is a function of the angular position of the third magnet. An output is generated indicative of the phase difference between the two waveforms.

  3. HIGH TEMPERATURE HIGH PRESSURE THERMODYNAMIC MEASUREMENTS FOR COAL MODEL COMPOUNDS

    SciTech Connect

    Vinayak N. Kabadi

    2000-05-01

    The flow VLE apparatus designed and built for a previous project was upgraded and recalibrated for data measurements for this project. The modifications include better and more accurate sampling technique, addition of a digital recorder to monitor temperature and pressure inside the VLE cell, and a new technique for remote sensing of the liquid level in the cell. VLE data measurements for three binary systems, tetralin-quinoline, benzene--ethylbenzene and ethylbenzene--quinoline, have been completed. The temperature ranges of data measurements were 325 C to 370 C for the first system, 180 C to 300 C for the second system, and 225 C to 380 C for the third system. The smoothed data were found to be fairly well behaved when subjected to thermodynamic consistency tests. SETARAM C-80 calorimeter was used for incremental enthalpy and heat capacity measurements for benzene--ethylbenzene binary liquid mixtures. Data were measured from 30 C to 285 C for liquid mixtures covering the entire composition range. An apparatus has been designed for simultaneous measurement of excess volume and incremental enthalpy of liquid mixtures at temperatures from 30 C to 300 C. The apparatus has been tested and is ready for data measurements. A flow apparatus for measurement of heat of mixing of liquid mixtures at high temperatures has also been designed, and is currently being tested and calibrated.

  4. Rotational viscometer for high-pressure, high-temperature fluids

    DOEpatents

    Carr, K.R.

    1983-06-06

    The invention is a novel rotational viscometer which is well adapted for use with fluids at high temperatures and/or pressures. In one embodiment, the viscometer include a substantially non-magnetic tube having a closed end and having an open end in communication with a fluid whose viscosity is to be determined. An annular drive magnet is mounted for rotation about the tube. The tube encompasses and supports a rotatable shaft assembly which carries a rotor, or bob, for insertion in the fluid. Affixed to the shaft are (a) a second magnet which is magnetically coupled to the drive magnet and (b) a third magnet. In a typical operation, the drive magnet is rotated to turn the shaft assembly while the shaft rotor is immersed in the fluid. The viscous drag on the rotor causes the shaft assembly to lag the rotation of the drive magnet by an amount which is a function of the amount of viscous drag. A first magnetic pickup generates a waveform whose phase is a function of the angular position of the drive magnet. A second magnetic pickup generates a waveform whose phase is a function of the angular position of the third magnet. Means are provided to generate an output indicative of the phase difference between the two waveforms. The viscometer is comparatively simple, inexpensive, rugged, and does not require shaft seals.

  5. Rotational viscometer for high-pressure, high-temperature fluids

    NASA Astrophysics Data System (ADS)

    Carr, K. R.

    1983-06-01

    The invention is a novel rotational viscometer which is well adapted for use with fluids at high temperatures and/or pressures. In one embodiment, the viscometer includes a substantially nonmagnetic tube having a closed and having an open end in communication with a fluid whose viscosity is to be determined. An annular drive magnet is mounted for rotation about the tube. The tube encompasses and supports a rotatable shaft assembly which carries a rotor, or bob, for insertion in the fluid. Affixed to the shaft are a second magnet which is magnetically coupled to the drive magnet and a third magnet. In a typical operation, the drive magnet is rotated to turn the shaft assembly while the shaft rotor is immersed in the fluid. The viscous drag. A first magnetic pickup generates a waveform whose phase is a function of the angular position of the drive magnet. A second magnetic pickup generates a waveform whose phase is a function of the angular position of the third magnet. Means are provided to generate an output indicative of the phase difference between the two waveforms. The viscometer is comparatively simple, inexpensive, rugged, and does not require shaft seals.

  6. Estimating Shock Pressures in Chondrites From High-Pressure Minerals in Shock-induced Melt Veins

    NASA Astrophysics Data System (ADS)

    Xie, Z.; Sharp, T. G.

    2002-12-01

    High-pressure minerals are common in highly shocked (S6) L6 chondrites, occurring within or adjacent to shock-induced melt veins and melt pockets. They provide natural examples of high-pressure minerals that make up the Earth's transition zone (410 to 660 km depth) and lower mantle, as well as a record of high-pressure and temperature conditions during impact events on chondrite parent bodies. The high-pressure minerals that crystallize in melt veins and pockets can be used as an alternative means of investigating shock pressure. We used transmission electron microscopy (TEM) to characterize the shock-vein mineralogy in seven L6 chondrites ranging from shock stage S6 to S3: Tenham (S6), Umbarger (S6), Roy (S3-5), Ramsdorf (S4), Kunashak (S4), Nakhon Pathon (S4) and La Lande (S4). Tenham contains assemblages that reflect variable cooling rates during crystallization. Majorite plus magnesiow\\x81stite occur in the center of melt veins, whereas ringwoodite, akimotoite and round amorphous grains (probably vitrified MgSiO3-pervoskite) occur along melt-vein edges. In addition, a symplectitic intergrowth of majorite and an amorphous phase has been observed, which probably represents clinopyroxene that has disassociated into majorite plus CaSiO3-pervoskite. High pressure minerals in the Umbarger melt veins include: ringwoodite, akimotoite ((Mg,Fe)SiO3-ilmenite), augite, and hollandite-structured plagioclase. In addition, Fe2SiO4-spinel (new mineral) and stishovite occur in SiO2-FeO rich melt. High-pressure minerals in the Roy melt veins include ringwoodite and majorite. Melt veins in Ramsdorf, Kunashak, Nakhon Pathon and La lande contain fine-grained olivines and pyroxenes that are defect free and interpreted as having crystallized from the melt. Crystallization pressures can be inferred from the mineral assemblages in the melt veins and available phase equilibrium data. Melt veins in Tenham crystallized at pressure of approximately 25 GPa; Umbarger at pressure between 18 to 25 GPa; Roy at pressure between 14 to 22 GPa; Ramsdort, Kunashak, Nakhon Pathon and La lande at pressure up to to15 GPa.

  7. New iron hydrides under high pressure.

    PubMed

    Pépin, Charles M; Dewaele, Agnès; Geneste, Grégory; Loubeyre, Paul; Mezouar, Mohamed

    2014-12-31

    The Fe-H system has been investigated by combined x-ray diffraction studies and total energy calculations at pressures up to 136 GPa. The experiments involve laser annealing of hydrogen-embedded iron in a diamond anvil cell. Two new FeHx compounds, with x?2 and x=3, are discovered at 67 and 86 GPa, respectively. Their crystal structures are identified (unit cell and Fe positional parameters from x-ray diffraction, H positional parameters from ab initio calculations) as tetragonal with space group I4/mmm for FeH(?2) and as simple cubic with space group Pm3m for FeH3. Large metastability regimes are observed that allowed to measure the P(V) equation of state at room temperature of FeH, FeH(?2), and FeH3. PMID:25615354

  8. New Iron Hydrides under High Pressure

    NASA Astrophysics Data System (ADS)

    Pépin, Charles M.; Dewaele, Agnès; Geneste, Grégory; Loubeyre, Paul; Mezouar, Mohamed

    2014-12-01

    The Fe-H system has been investigated by combined x-ray diffraction studies and total energy calculations at pressures up to 136 GPa. The experiments involve laser annealing of hydrogen-embedded iron in a diamond anvil cell. Two new FeHx compounds, with x ˜2 and x =3 , are discovered at 67 and 86 GPa, respectively. Their crystal structures are identified (unit cell and Fe positional parameters from x-ray diffraction, H positional parameters from ab initio calculations) as tetragonal with space group I 4 /m m m for FeH˜2 and as simple cubic with space group P m 3 ¯ m for FeH3 . Large metastability regimes are observed that allowed to measure the P (V ) equation of state at room temperature of FeH, FeH˜2 , and FeH3 .

  9. High-pressure optical combustion probe

    SciTech Connect

    Woodruff, S.D.

    1996-12-31

    An optical access probe was developed to meet the demands of a gas turbine combustor in a Cooperative Research and Development Agreement (CRADA) with the Westinghouse Science and Technology Center. The probe is water-cooled, has no external fittings, and is pressure-sealed with a conventional compression fitting. The probe utilizes a 1.0-mm diameter sapphire rod as a lightpipe for optical access and fiber optic coupling to the spectroscopic experiments. This is coupled with a fused silica optical fiber to the optical experiments employed to study the combustion process. The probe has been tested to 10{sup 6} Pa in a test combustor exhibiting 10{sup 5} Pa instability oscillations. To test its spectral range, the probe investigated OH emissions at 310 nm, C{sub 2} and CH emissions from 400 to 500 nm, Near IR emissions from 800 to 1,800 nm, and temperature measurements using an Accufiber detection system.

  10. A high-temperature wideband pressure transducer

    NASA Technical Reports Server (NTRS)

    Zuckerwar, A. J.

    1977-01-01

    A condenser microphone AM carrier system, which has been developed to measure pressure fluctuations at elevated temperatures, consists of the following components: a condenser microphone designed for operation at elevated temperatures; existing carrier electronics developed under two previous research grants but adapted to meet present requirements; a 6 m cable operating as a half-wavelength transmission line between the microphone and carrier electronics; and a voltage-controlled oscillator used in a feedback loop for automatic tuning control. Both theoretical and practical aspects of the development program are considered. The three predominant effects of temperature changes are changes in the membrane-backplate gap, membrane tension, and air viscosity. The microphone is designed so that changes in gap and membrane tension tend to have compensating effects upon the microphone sensitivity.

  11. Laser-machined microcavities for simultaneous measurement of high-temperature and high-pressure.

    PubMed

    Ran, Zengling; Liu, Shan; Liu, Qin; Huang, Ya; Bao, Haihong; Wang, Yanjun; Luo, Shucheng; Yang, Huiqin; Rao, Yunjiang

    2014-01-01

    Laser-machined microcavities for simultaneous measurement of high-temperature and high-pressure are demonstrated. These two cascaded microcavities are an air cavity and a composite cavity including a section of fiber and an air cavity. They are both placed into a pressure chamber inside a furnace to perform simultaneous pressure and high-temperature tests. The thermal and pressure coefficients of the short air cavity are ~0.0779 nm/°C and ~1.14 nm/MPa, respectively. The thermal and pressure coefficients of the composite cavity are ~32.3 nm/°C and ~24.4 nm/MPa, respectively. The sensor could be used to separate temperature and pressure due to their different thermal and pressure coefficients. The excellent feature of such a sensor head is that it can withstand high temperatures of up to 400 °C and achieve precise measurement of high-pressure under high temperature conditions. PMID:25106018

  12. Laser-Machined Microcavities for Simultaneous Measurement of High-Temperature and High-Pressure

    PubMed Central

    Ran, Zengling; Liu, Shan; Liu, Qin; Huang, Ya; Bao, Haihong; Wang, Yanjun; Luo, Shucheng; Yang, Huiqin; Rao, Yunjiang

    2014-01-01

    Laser-machined microcavities for simultaneous measurement of high-temperature and high-pressure are demonstrated. These two cascaded microcavities are an air cavity and a composite cavity including a section of fiber and an air cavity. They are both placed into a pressure chamber inside a furnace to perform simultaneous pressure and high-temperature tests. The thermal and pressure coefficients of the short air cavity are ?0.0779 nm/°C and ?1.14 nm/MPa, respectively. The thermal and pressure coefficients of the composite cavity are ?32.3 nm/°C and ?24.4 nm/MPa, respectively. The sensor could be used to separate temperature and pressure due to their different thermal and pressure coefficients. The excellent feature of such a sensor head is that it can withstand high temperatures of up to 400 °C and achieve precise measurement of high-pressure under high temperature conditions. PMID:25106018

  13. Chemistry of nitromethane at very high pressure

    SciTech Connect

    Agnew, S.F.; Swanson, B.I.; Kenney, J.; Kenney, I.

    1989-01-01

    Decomposition of nitromethane is reported over the range of 115- 180/degree/C and 0.6-8.5 GPa. About 5 /mu/g of nitromethane is compressed with a diamond-anvil cell, heated to the point that reaction occurs, and held typically 10-20 minutes at the reaction temperature. The cell is cooled and the volatile contents of the cell are frozen as a thin layer in vacuo and an infrared absorption spectrum is recorded. The three volatile products observed are N/sub 2/O, CO/sub 2/, and water, with N/sub 2/O production peaking at 1.5 GPa, 135/degree/C, and 35% of NME; CO/sub 2/ production peaking at 3.5 GPa, 135/degree/C, and 65% of NME, and water yields at 20-50% of NME at the highest pressure measured, 8.5 GPa and 175/degree/C. Water yields were difficult to quantify due to background contamination. Results indicate three different reactions for solid NME dependent primarily on the pressure of the reaction, and that fluid NME does not decompose at 0.6 GPa and 175/degree/C, although the solid decomposes readily at 1.1 GPa and 120/degree/C. The authors conclude that, while various decomposition mechanisms are possible, the initial step CH/sub 3/NO/sub 2/ /yields/ /center dot/CH/sub 3/ + /center dot/NO/sub 2/ is very unlikely. 14 refs., 5 figs.

  14. Energy Systems High Pressure Test Laboratory (Fact Sheet)

    SciTech Connect

    Not Available

    2011-10-01

    This fact sheet describes the purpose, lab specifications, applications scenarios, and information on how to partner with NREL's Energy Systems High Pressure Test Laboratory at the Energy Systems Integration Facility. The purpose of the Energy Systems High Pressure Test Laboratory at NREL's Energy Systems Integration Facility (ESIF) is to provide space where high pressure hydrogen components can be safely tested. High pressure hydrogen storage is an integral part of energy storage technology for use in fuel cell and in other distributed energy scenarios designed to effectively utilize the variability inherent with renewable energy sources. The high pressure storage laboratory is co-located with energy storage activities such as ultra-capacitors, super conducting magnetic flywheel and mechanical energy storage systems laboratories for an integrated approach to system development and demonstration. Hazards associated with hydrogen storage at pressures up to 10,000 psi include oxygen displacement, combustion, explosion, and pressurization of room air due to fast release and physical hazards associated with burst failure modes. A critical understanding of component failure modes is essential in developing reliable, robust designs that will minimize failure risk beyond the end of service life. Development of test protocol for accelerated life testing to accurately scale to real world operating conditions is essential for developing regulations, codes and standards required for safe operation. NREL works closely with industry partners in providing support of advanced hydrogen technologies. Innovative approaches to product design will accelerate commercialization into new markets. NREL works with all phases of the product design life cycle from early prototype development to final certification testing. High pressure tests are performed on hydrogen components, primarily for the validation of developing new codes and standards for high pressure hydrogen applications. The following types of tests can be performed: Performance, Component and system level efficiency, Strength of materials and hydrogen compatibility, Safety demonstration, Model validation, and Life cycle reliability.

  15. Ris0-R-828(EN) Practical Means for

    E-print Network

    Environments 10 .1 Fire hosing 11 2.3. High pressure water hosing 12 2b High pressure water hosing 13 .3 Dry wooden surfaces and painted roofs 28 .14.b Scraping wooden surfaces and painted roofs 29 . 15 Dismantling

  16. High pressure working mode of hollow cathode arc discharges

    NASA Technical Reports Server (NTRS)

    Minoo, H.; Popovici, C.

    1985-01-01

    The behavior of high pressure cathotrons is discussed. Methods of preheating either the gas or the cathode itself are detailed together with various geometries for the hollow cathode. Three special configurations were tested, and the results are analyzed.

  17. The value of high-pressure hysterosalpingography with new cannula.

    PubMed

    Totani, R

    1982-01-01

    To achieve maximum dilatation of the Fallopian tubes so as to improve the pregnancy: non-pregnancy ratio of hysterosalpingography (HSG) treatment, a high-pressure injection technique was evaluated. For this purpose a disposable cannula and an adapted pair of tenacula were developed and a remote-control procedure using an auto-injector and an adapted pressure recorder was used to assure the safety of doctors and staff. 1780 cases who underwent 400 mmHg high-pressure HSG treatment were compared with 903 conventional HSG cases. Results indicated a higher pregnancy ratio for the high-pressure experimental group after treatment. In addition, it was found that side effects due to the use of disposable cannula and highly viscous water-soluble mediums developed for use in angiography were less common than for conventional materials. PMID:7152089

  18. 2. SOUTHEAST SIDE. HIGH PRESSURE HELIUM STORAGE TANKS AT LEFT. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. SOUTHEAST SIDE. HIGH PRESSURE HELIUM STORAGE TANKS AT LEFT. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Helium Compression Plant, Test Area 1-115, intersection of Altair & Saturn Boulevards, Boron, Kern County, CA

  19. Heart and Artery Damage and High Blood Pressure

    MedlinePLUS

    ... lead to heart failure? HBP damages the entire circulatory system. "Heart failure" is the term used for a ... body. High blood pressure damages the entire complex circulatory system. As mentioned above, HBP creates conditions for blocked ...

  20. DETAIL VIEW OF UNIT #3 WITH HIGH PRESSURE STAGE COMPRESSOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW OF UNIT #3 WITH HIGH PRESSURE STAGE COMPRESSOR IN LEFT FOREGROUND. - Burnsville Natural Gas Pumping Station, Saratoga Avenue between Little Kanawha River & C&O Railroad line, Burnsville, Braxton County, WV

  1. Detail view of unit 43 with high pressure stage compressor ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view of unit 43 with high pressure stage compressor in left foreground. - Burnsville Natural Gas Pumping Station, Saratoga Avenue between Little Kanawha River & C&O Railroad line, Burnsville, Braxton County, WV

  2. Detail view of valve mechanisms and goverenor on high pressure ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view of valve mechanisms and goverenor on high pressure stage engine of unit 43. - Burnsville Natural Gas Pumping Station, Saratoga Avenue between Little Kanawha River & C&O Railroad line, Burnsville, Braxton County, WV

  3. 'Weird' crystal structures of elements at high pressure

    Microsoft Academic Search

    Tat'yana N Kolobyanina

    2002-01-01

    New crystal structures, in particular incommensurate composite crystals, discovered in the high-pressure phases of Group I, II, IV, and V elements are described, and their intermetallic and other binary structural analogs are discussed.

  4. 143. MOBILE HIGH PRESSURE NITROGEN CART STORED IN CONTROL ROOM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    143. MOBILE HIGH PRESSURE NITROGEN CART STORED IN CONTROL ROOM (214), LSB (BLDG. 751) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  5. 46 CFR 153.1011 - Changing containment systems and hoses to and from alkylene oxide service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...hose marked “For Alkylene Oxide Transfer Only” is used for...cargo other than an alkylene oxide. (b) The following cargoes...particularly reactive with alkylene oxides: (1) Non-oxidizing mineral...2) Sulfuric acid; (3) Nitric acid; (4) Organic...

  6. 46 CFR 153.1011 - Changing containment systems and hoses to and from alkylene oxide service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...hose marked “For Alkylene Oxide Transfer Only” is used for...cargo other than an alkylene oxide. (b) The following cargoes...particularly reactive with alkylene oxides: (1) Non-oxidizing mineral...2) Sulfuric acid; (3) Nitric acid; (4) Organic...

  7. 46 CFR 153.1011 - Changing containment systems and hoses to and from alkylene oxide service.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...hose marked “For Alkylene Oxide Transfer Only” is used for...cargo other than an alkylene oxide. (b) The following cargoes...particularly reactive with alkylene oxides: (1) Non-oxidizing mineral...2) Sulfuric acid; (3) Nitric acid; (4) Organic...

  8. 46 CFR 153.1011 - Changing containment systems and hoses to and from alkylene oxide service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...hose marked “For Alkylene Oxide Transfer Only” is used for...cargo other than an alkylene oxide. (b) The following cargoes...particularly reactive with alkylene oxides: (1) Non-oxidizing mineral...2) Sulfuric acid; (3) Nitric acid; (4) Organic...

  9. 46 CFR 153.1011 - Changing containment systems and hoses to and from alkylene oxide service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...hose marked “For Alkylene Oxide Transfer Only” is used for...cargo other than an alkylene oxide. (b) The following cargoes...particularly reactive with alkylene oxides: (1) Non-oxidizing mineral...2) Sulfuric acid; (3) Nitric acid; (4) Organic...

  10. 30 CFR 75.1103-11 - Tests of fire hydrants and fire hose; record of tests.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Tests of fire hydrants and fire hose; record of tests...Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION...DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Fire Protection §...

  11. 30 CFR 75.1103-11 - Tests of fire hydrants and fire hose; record of tests.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Tests of fire hydrants and fire hose; record of tests...Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION...DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Fire Protection §...

  12. 30 CFR 75.1103-11 - Tests of fire hydrants and fire hose; record of tests.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Tests of fire hydrants and fire hose; record of tests...Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION...DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Fire Protection §...

  13. 30 CFR 75.1103-11 - Tests of fire hydrants and fire hose; record of tests.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Tests of fire hydrants and fire hose; record of tests...Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION...DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Fire Protection §...

  14. 30 CFR 75.1103-11 - Tests of fire hydrants and fire hose; record of tests.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Tests of fire hydrants and fire hose; record of tests...Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION...DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Fire Protection §...

  15. Retrieval Pump Flexible Suction Hose Dynamic Response Induced by Impact of a Mixer Pump Jet

    SciTech Connect

    Enderlin, C.W.; Terrones, G.; Bamberger, J.A.; White, M.; Combs, W.H.

    1999-10-07

    Experiments were conducted to investigate whether it may be feasible to simultaneously mix and retrieve radioactive waste slurries that are stored in million-gallon, double-shell tanks at the Hanford Site in Richland, Washington. Oscillating mixer pumps, located near the floor of these tanks, are used to mobilize and mix the slurry prior to retrieval. Operational scenarios that may be beneficial for retrieval may require simultaneous operation of a decant/transfer pump and the jet mixer pumps. The effects of jet-induced agitation and jet impingement upon the decant/transfer pump's flexible suction hose have not previously been experimentally evaluated. Possible effects of the jet impacting the hose include hose fatigue, hose collision or entanglement with other structures, and induced static and dynamic loads on the decant/transfer pump equipment. The objective of this work was to create operating conditions in a test tank that produce a dynamic response (in the flexible suction hose upon impingement from an above-floor jet) that is similar to that anticipated in the actual tank. A scaling analysis was conducted to define the interactions between the jet, the tank floor and the suction hose. The complexity of scaling the multi-layer flexible hose (matching its hydroelastic parameters at full and 1/4-scale) led to an alternate approach, that of matching the expected full-scale forces on the full-scale hose in the scaled tank. Two types of tests were conducted: characterization of the jet velocity profile in the test tank at two axial locations from the nozzle and observation of the motion induced in the flexible retrieval hose from impact by the jet. The velocity profile of the jet in the test tank was measured to compare the measured profiles with profile predictions for an above-floor jet. These data were used to obtain a refined estimate of the velocity profile and therefore, the force acting upon the test article at a particular location in the tank. The hose motion and location within the test tank resulting from jet impingement were recorded by video. This visual record can be correlated with the data recorded by the data acquisition system. These data coupled with the velocity profile results, were used to estimate the forces required to induce motion in the hose.

  16. Effect of ultra-high hydrostatic pressure on hydrosoluble vitamins

    Microsoft Academic Search

    Félix Sancho; Yann Lambert; Gérard Demazeau; Alain Largeteau; Jean-Marie Bouvier; Jean-François Narbonne

    1999-01-01

    The effect of ultra-high hydrostatic pressure on selected hydrosoluble vitamins (B1, B6 and C) is studied. Vitamin retention after pressurization has been compared to that induced by several classic food processing treatments, such as pasteurization or sterilization. Ascorbate, pyridoxal, and thiamin hydrochloride, included in a multivitamin model system (mvMS), are analyzed by high performance liquid chromatography (HPLC), and under current

  17. Stabilization of a high-pressure arc in hydrogen

    Microsoft Academic Search

    E. A. Ershov-Pavlov; L. E. Krat'ko; N. I. Chubruk; V. D. Shimanovich

    1987-01-01

    The authors describe hydrogen plasma sources with densities of approx. 10¹⁸ cm⁻³ for investigating spectral optical characteristics. The plasma is created using a gas vortex-stabilized arc at high atmospheric pressures. A system is described that includes an electrical discharge high-pressure chamber and an arc feed source, and the arc characteristics for a large current i = 2-8 A at a

  18. High pressure water jet cutting of sugar cane 

    E-print Network

    Valco, Thomas Donald

    1977-01-01

    : Agricultural Engineering HIGH PRESSURE WATER JET CUTTING OF SUGAR CANE A Thesis by THOMAS DONALD VALCO Approved as to style and content by: Dr. Charlie G. Coble (Chairman of Committee) Dr. Edward A. Haler (Head of Department) Mr. William H. Aldred... encourage- ment to test the idea. Two companies which were involved in the tests were: Flow Research, Inc. and McCartney Engineering. Both have developed industrial high pressure water jet cutting equipment. OBJECTIVES AND SCOPE The first objective...

  19. High pressure and multiferroics materials: a happy marriage

    PubMed Central

    Gilioli, Edmondo; Ehm, Lars

    2014-01-01

    The community of material scientists is strongly committed to the research area of multiferroic materials, both for the understanding of the complex mechanisms supporting the multiferroism and for the fabrication of new compounds, potentially suitable for technological applications. The use of high pressure is a powerful tool in synthesizing new multiferroic, in particular magneto-electric phases, where the pressure stabilization of otherwise unstable perovskite-based structural distortions may lead to promising novel metastable compounds. The in situ investigation of the high-pressure behavior of multiferroic materials has provided insight into the complex interplay between magnetic and electronic properties and the coupling to structural instabilities. PMID:25485138

  20. Stabilization of a high-pressure arc in hydrogen

    SciTech Connect

    Ershov-Pavlov, E.A.; Krat'ko, L.E.; Chubruk, N.I.; Shimanovich, V.D.

    1987-09-01

    The authors describe hydrogen plasma sources with densities of approx. 10/sup 18/ cm/sup -3/ for investigating spectral optical characteristics. The plasma is created using a gas vortex-stabilized arc at high atmospheric pressures. A system is described that includes an electrical discharge high-pressure chamber and an arc feed source, and the arc characteristics for a large current i = 2-8 A at a pressure of p = (1-30) x 10/sup 5/ Pa and the hydrogen plasma parameters are given.

  1. High pressure and multiferroics materials: a happy marriage.

    PubMed

    Gilioli, Edmondo; Ehm, Lars

    2014-11-01

    The community of material scientists is strongly committed to the research area of multiferroic materials, both for the understanding of the complex mechanisms supporting the multiferroism and for the fabrication of new compounds, potentially suitable for technological applications. The use of high pressure is a powerful tool in synthesizing new multiferroic, in particular magneto-electric phases, where the pressure stabilization of otherwise unstable perovskite-based structural distortions may lead to promising novel metastable compounds. The in situ investigation of the high-pressure behavior of multiferroic materials has provided insight into the complex interplay between magnetic and electronic properties and the coupling to structural instabilities. PMID:25485138

  2. Very high pressure Moessbauer spectroscopy using diamond anvil cells

    SciTech Connect

    Pasternak, M.P.; Taylor, R.D.

    1988-01-01

    The technique of generating very high pressure by means of Diamond Anvil Cells (DAC) for Mossbauer Effect applications is outlined. A comprehensive description is presented of the principles of DAC, modification for the use in M/umlt o/ssbauer Spectroscopy (MS), the Merrill--Bassett and Bassett cells, of pressure measurements, of gasketing and collimation, and of hydrostatic media. Examples of /sup 151/Eu, /sup 119/Sn and /sup 129/I are given showing the feasibility of DAC applications in MS. Other isotopes with potential use for high pressure MS using DAC are suggested. 27 refs., 9 figs.

  3. Poisson's Ratio and the Densification of Glass under High Pressure

    SciTech Connect

    Rouxel, T.; Ji, H. [Applied Mechanics Laboratory of the University of Rennes 1, LARMAUR, Universite de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex (France); Hammouda, T. [Laboratoire Magmas et Volcans, CNRS-OPG , Universite Blaise Pascal, 5 rue Kessler, 63038 Clermont-Ferrand cedex (France); Moreac, A. [IPR, CNRS-Universite de Rennes 1, Campus de Beaulieu, 35042 Rennes cedex (France)

    2008-06-06

    Because of a relatively low atomic packing density, (C{sub g}) glasses experience significant densification under high hydrostatic pressure. Poisson's ratio ({nu}) is correlated to C{sub g} and typically varies from 0.15 for glasses with low C{sub g} such as amorphous silica to 0.38 for close-packed atomic networks such as in bulk metallic glasses. Pressure experiments were conducted up to 25 GPa at 293 K on silica, soda-lime-silica, chalcogenide, and bulk metallic glasses. We show from these high-pressure data that there is a direct correlation between {nu} and the maximum post-decompression density change.

  4. Escherichia coli mutants resistant to inactivation by high hydrostatic pressure.

    PubMed Central

    Hauben, K J; Bartlett, D H; Soontjens, C C; Cornelis, K; Wuytack, E Y; Michiels, C W

    1997-01-01

    Alternating cycles of exposure to high pressure and outgrowth of surviving populations were used to select for highly pressure-resistant mutants of Escherichia coli MG1655. Three barotolerant mutants (LMM1010, LMM1020, and LMM1030) were isolated independently by using outgrowth temperatures of 30, 37, and 42 degrees C, respectively. Survival of these mutants after pressure treatment for 15 min at ambient temperature was 40 to 85% at 220 MPa and 0.5 to 1.5% at 800 MPa, while survival of the parent strain, MG1655, decreased from 15% at 220 MPa to 2 x 10(-8)% at 700 MPa. Heat resistance of mutants LMM1020 and LMM1030 was also altered, as evident by higher D values at 58 and 60 degrees C and reduced z values compared to those for the parent strain. D and z values for mutant LMM1010 were not significantly different from those for the parent strain. Pressure sensitivity of the mutants increased from 10 to 50 degrees C, as opposed to the parent strain, which showed a minimum around 40 degrees C. The ability of the mutants to grow at moderately elevated pressure (50 MPa) was reduced at temperatures above 37 degrees C, indicating that resistance to pressure inactivation is unrelated to barotolerant growth. The development of high levels of barotolerance as demonstrated in this work should cause concern about the safety of high-pressure food processing. PMID:9055412

  5. High-pressure crystallography of periodic and aperiodic crystals.

    PubMed

    Hejny, Clivia; Minkov, Vasily S

    2015-03-01

    More than five decades have passed since the first single-crystal X-ray diffraction experiments at high pressure were performed. These studies were applied historically to geochemical processes occurring in the Earth and other planets, but high-pressure crystallography has spread across different fields of science including chemistry, physics, biology, materials science and pharmacy. With each passing year, high-pressure studies have become more precise and comprehensive because of the development of instrumentation and software, and the systems investigated have also become more complicated. Starting with crystals of simple minerals and inorganic compounds, the interests of researchers have shifted to complicated metal-organic frameworks, aperiodic crystals and quasicrystals, molecular crystals, and even proteins and viruses. Inspired by contributions to the microsymposium 'High-Pressure Crystallography of Periodic and Aperiodic Crystals' presented at the 23rd IUCr Congress and General Assembly, the authors have tried to summarize certain recent results of single-crystal studies of molecular and aperiodic structures under high pressure. While the selected contributions do not cover the whole spectrum of high-pressure research, they demonstrate the broad diversity of novel and fascinating results and may awaken the reader's interest in this topic. PMID:25866659

  6. Gas Viscosity at High Pressure and High Temperature 

    E-print Network

    Ling, Kegang

    2012-02-14

    . Although viscosity of some pure components such as methane, ethane, propane, butane, nitrogen, carbon dioxide and binary mixtures of these components at low-intermediate pressure and temperature had been studied intensively and been understood thoroughly...

  7. Experimental study on pressure drop of bends in dense phase pneumatic conveying under high pressure

    NASA Astrophysics Data System (ADS)

    Yuan, Gaoyang; Liang, Cai; Chen, Xiaoping; Xu, Pan; Xu, Guiling; Shen, Liu

    2014-04-01

    The transport test using nitrogen as conveying gas are carried out at high operating pressure up to 4MPa in the experimental equipment for dense phase pneumatic conveying. The transport powders in the experiment are anthracite coal and petroleum coke. The pressure drop characteristics in bends are acquired with the different transport powder. The experimental results show that under the similar mass flow, the pressure drop of vertical upward bend is greater than the horizontal bend and the horizontal bend is greater than the vertical downward bend at the same superficial gas velocity, while there is a best superficial gas velocity minimizes the pressure drop of the bend. Under the similar mass flow rate and the similar particle size, the pressure drop of the bend with the petroleum coke is greater than the pressure drop with the anthracite coal as the same superficial gas velocity. According to Barth's additional pressure drop method, the pressure drop fitting formulas of the vertical upward bend, the horizontal bend and the vertical downward bend are obtained, and the predicted results are in accordance with that of the experiments.

  8. Low Cost, High Efficiency, High Pressure Hydrogen Storage

    SciTech Connect

    Mark Leavitt

    2010-03-31

    A technical and design evaluation was carried out to meet DOE hydrogen fuel targets for 2010. These targets consisted of a system gravimetric capacity of 2.0 kWh/kg, a system volumetric capacity of 1.5 kWh/L and a system cost of $4/kWh. In compressed hydrogen storage systems, the vast majority of the weight and volume is associated with the hydrogen storage tank. In order to meet gravimetric targets for compressed hydrogen tanks, 10,000 psi carbon resin composites were used to provide the high strength required as well as low weight. For the 10,000 psi tanks, carbon fiber is the largest portion of their cost. Quantum Technologies is a tier one hydrogen system supplier for automotive companies around the world. Over the course of the program Quantum focused on development of technology to allow the compressed hydrogen storage tank to meet DOE goals. At the start of the program in 2004 Quantum was supplying systems with a specific energy of 1.1-1.6 kWh/kg, a volumetric capacity of 1.3 kWh/L and a cost of $73/kWh. Based on the inequities between DOE targets and Quantum’s then current capabilities, focus was placed first on cost reduction and second on weight reduction. Both of these were to be accomplished without reduction of the fuel system’s performance or reliability. Three distinct areas were investigated; optimization of composite structures, development of “smart tanks” that could monitor health of tank thus allowing for lower design safety factor, and the development of “Cool Fuel” technology to allow higher density gas to be stored, thus allowing smaller/lower pressure tanks that would hold the required fuel supply. The second phase of the project deals with three additional distinct tasks focusing on composite structure optimization, liner optimization, and metal.

  9. Generalization of low pressure, gas-liquid, metastable sound speed to high pressures

    NASA Technical Reports Server (NTRS)

    Bursik, J. W.; Hall, R. M.

    1981-01-01

    A theory is developed for isentropic metastable sound propagation in high pressure gas-liquid mixtures. Without simplification, it also correctly predicts the minimum speed for low pressure air-water measurements where other authors are forced to postulate isothermal propagation. This is accomplished by a mixture heat capacity ratio which automatically adjusts from its single phase values to approximately the isothermal value of unity needed for the minimum speed. Computations are made for the pure components parahydrogen and nitrogen, with emphasis on the latter. With simplifying assumptions, the theory reduces to a well known approximate formula limited to low pressure.

  10. Confinement of hydrogen at high pressure in carbon nanotubes

    DOEpatents

    Lassila, David H. (Aptos, CA); Bonner, Brian P. (Livermore, CA)

    2011-12-13

    A high pressure hydrogen confinement apparatus according to one embodiment includes carbon nanotubes capped at one or both ends thereof with a hydrogen-permeable membrane to enable the high pressure confinement of hydrogen and release of the hydrogen therethrough. A hydrogen confinement apparatus according to another embodiment includes an array of multi-walled carbon nanotubes each having first and second ends, the second ends being capped with palladium (Pd) to enable the high pressure confinement of hydrogen and release of the hydrogen therethrough as a function of palladium temperature, wherein the array of carbon nanotubes is capable of storing hydrogen gas at a pressure of at least 1 GPa for greater than 24 hours. Additional apparatuses and methods are also presented.

  11. High-pressure trickle-bed reactors: A review

    SciTech Connect

    Al-Dahhan, M.H.; Dudukovic, M.P. [Washington Univ., St. Louis, MO (United States)] [Washington Univ., St. Louis, MO (United States); Larachi, F. [Laval Univ., Quebec City, Quebec (Canada). Dept. of Chemical Engineering] [Laval Univ., Quebec City, Quebec (Canada). Dept. of Chemical Engineering; Laurent, A. [Lab. des Sciences du Genie Chimique, Nancy (France)] [Lab. des Sciences du Genie Chimique, Nancy (France)

    1997-08-01

    A concise review of relevant experimental observations and modeling of high-pressure trickle-bed reactors, based on recent studies, is presented. The following topics are considered: flow regime transitions, pressure drop, liquid holdup, gas-liquid interfacial area and mass-transfer coefficient, catalyst wetting efficiency, catalyst dilution with inert fines, and evaluation of trickle-bed models for liquid-limited and gas-limited reactions. The effects of high-pressure operation which is of industrial relevance, on the physicochemical and fluid dynamic parameters are discussed. Empirical and theoretical models developed to account for the effect of high pressure on the various parameters and phenomena pertinent to the topics discussed are briefly described. 200 refs.

  12. High-Pressure Gaseous Burner (HPGB) Facility Became Operational

    NASA Technical Reports Server (NTRS)

    Nguyen, Quang-Viet

    2003-01-01

    A gas-fueled high-pressure combustion facility with optical access, developed over the last 3 years, is now collecting research data in a production mode. The High-Pressure Gaseous Burner (HPGB) rig at the NASA Glenn Research Center can operate at sustained pressures up to 60 atm with a variety of gaseous fuels and liquid jet fuel. The facility is unique because it is the only continuous-flow, hydrogen-capable 60-atm rig in the world with optical access. It will provide researchers with new insights into flame conditions that simulate the environment inside the ultra-high-pressure-ratio combustion chambers of tomorrow s advanced aircraft engines. The facility provides optical access to the flame zone through four fused-silica optical windows, enabling the calibration of nonintrusive optical diagnostics to measure chemical species and temperature. The data from the HPGB rig enable the validation of numerical codes that simulate gas turbine combustors.

  13. Three precision differential pressure indicators for operation at high temperatures and pressures

    E-print Network

    Osburn, Douglas Clayton

    1981-01-01

    , high temperature electrical feedthroughs, and expensive double-shielded cable and connectors. Feedthroughs such as these are not commercially available and are extremely difficult to fabricate for operation at the desired conditions. Furthermore... at temperatures greater than 473 K or pressures above 20 NPa. Such gauges also are susceptible to corrosion under these harsh conditions. The objective of this work was to develop a differential pressure indicator for operation in these hostile environments...

  14. Boron under Pressure: Phase Diagram and Novel High-Pressure Phase

    Microsoft Academic Search

    Artem R. Oganov

    \\u000a Boron has a unique chemistry, responsible for remarkable complexities even in the pure element. I review some of the history\\u000a of the discovery of this element, and recent surprises found in boron under pressure. I discuss the recent discovery of a\\u000a new high-pressure phase, ?-B28, consisting of icosahedral B12 clusters and B2 pairs in a NaCl-type arrangement: (B2)?+(B12)?-, and displaying

  15. Opportunities and challenges in high pressure processing of foods.

    PubMed

    Rastogi, N K; Raghavarao, K S M S; Balasubramaniam, V M; Niranjan, K; Knorr, D

    2007-01-01

    Consumers increasingly demand convenience foods of the highest quality in terms of natural flavor and taste, and which are free from additives and preservatives. This demand has triggered the need for the development of a number of nonthermal approaches to food processing, of which high-pressure technology has proven to be very valuable. A number of recent publications have demonstrated novel and diverse uses of this technology. Its novel features, which include destruction of microorganisms at room temperature or lower, have made the technology commercially attractive. Enzymes and even spore forming bacteria can be inactivated by the application of pressure-thermal combinations, This review aims to identify the opportunities and challenges associated with this technology. In addition to discussing the effects of high pressure on food components, this review covers the combined effects of high pressure processing with: gamma irradiation, alternating current, ultrasound, and carbon dioxide or anti-microbial treatment. Further, the applications of this technology in various sectors - fruits and vegetables, dairy, and meat processing - have been dealt with extensively. The integration of high-pressure with other matured processing operations such as blanching, dehydration, osmotic dehydration, rehydration, frying, freezing / thawing and solid-liquid extraction has been shown to open up new processing options. The key challenges identified include: heat transfer problems and resulting non-uniformity in processing, obtaining reliable and reproducible data for process validation, lack of detailed knowledge about the interaction between high pressure, and a number of food constituents, packaging and statutory issues. PMID:17364696

  16. High-pressure intrapleural chemotherapy: feasibility in the pig model

    PubMed Central

    2012-01-01

    Background The usual treatments for pleural malignancies are mostly palliative. In contrast, peritoneal malignancies are often treated with a curative intent by cytoreductive surgery and intraperitoneal chemotherapy. As pressure has been shown to increase antitumor efficacy, we applied the concept of high-pressure intracavitary chemotherapy to the pleural space in a swine model. Methods Cisplatin and gemcitabine were selected because of their antineoplasic efficacy in vitro in a wide spectrum of cancer cell lines. The pleural cavity of 21 pigs was filled with saline solution; haemodynamic and respiratory parameters were monitored. The pressure was increased to 15-25 cm H2O. This treatment was associated with pneumonectomy in 6 pigs. Five pigs were treated with chemotherapy under pressure. Results The combination of gemcitabine (100 mg/l) and cisplatin (30 mg/l) was highly cytotoxic in vitro. The maximum tolerated pressure was 20 cm H20, due to haemodynamic failure. Pneumonectomy was not tolerated, either before or after pleural infusion. Five pigs survived intrapleural chemotherapy associating gemcitabine and cisplatin with 20 cm H2O pressure for 60 min. Conclusions High-pressure intrapleural chemotherapy is feasible in pigs. Further experiments will establish the pharmacokinetics and determine whether the benefit already shown in the peritoneum is also obtained in the pleura. PMID:22309737

  17. Causes of high pressure compressor deterioration in service

    NASA Technical Reports Server (NTRS)

    Richardson, J. H.; Sallee, G. P.; Smakula, F. K.

    1979-01-01

    The high mechanical reliability and low deterioration rate of the JT9D high-pressure compressor results in long utilization without exceeding engine operational limits. The increasing cost and decreasing supply of fuel have focused attention on the fuel burned implications of such high time use without refurbishment. The paper presents the results of JT9D high pressure compressor studies. The mechanical deterioration of the JT9D high-pressure compressor gaspath parts versus increasing service usage, documented from inspection of service parts, is presented and discussed including changes in airfoil roughness, blade length, airfoil contour and outer air seal trench characteristics. An estimate of the performance loss versus usage is related to each type of damage. The combined estimated high-pressure compressor performance loss for all mechanisms determined from part inspection is compared to historical engine test data to establish the validity of the predicted loss levels. The effect of cold section refurbishment on engine fuel consumption recovery and the results of an optimization study to determine the appropriate interval for high pressure compressor refurbishment are also reported.

  18. Superconductivity in the metallic elements at high pressures

    NASA Astrophysics Data System (ADS)

    Hamlin, J. J.

    2015-07-01

    Although the highest superconducting critical temperature, Tc , found in an elemental solid at ambient pressure is 9.2 K (niobium), under the application of ultra-high pressures, several elements exhibit Tc values near or above 20 K. This review includes a survey of the occurrence and understanding of pressure-induced superconductivity in the subset of elements that are metallic at ambient pressure. A particular focus is directed towards those elements that display the highest superconducting critical temperatures or exhibit substantial increases in Tc with pressure. A separate article in this issue by Shimizu will cover pressure-induced superconductivity in elements that are insulating at ambient pressure. - P.W. Bridgman (1935) [1].In the case of superconductivity, efforts to give an account of the effects of pressure on Tc have stimulated numerous insights into the conditions that are most favorable for superconductivity. With the extension of accessible pressures into the megabar range, made possible by the advent of diamond anvil cells, pressure has become an even more valuable tool in that relatively enormous changes in energy can be brought about. For example, the change in free energy (? P dV) resulting from compression to 100 GPa (1 megabar) can be on the order of hundreds of meV per atom or more. This is a large change compared to that obtained by cooling a material to low temperature (300K ? 25meV) or applying high magnetic fields (1?B × 100tesla ? 6meV).The study of pressure effects on elemental superconductors dates back almost as far as the discovery of superconductivity itself, with the first such study being performed in the laboratory of Kammerling Onnes in 1925 [6]. In that study, elemental tin was subjected to a modest pressure of roughly 300 bars and a small (5 mK) suppression of the superconducting critical temperature was observed. High pressure technology has since advanced tremendously, and it now is possible to subject matter to static pressures on the order of 300 GPa or more.Historically, experiments near the limits of achievable pressure have focused to a large extent on pure elemental solids. As the elemental solids have been studied at ever increasing pressures many elements that are not superconducting at ambient pressure have been found to be superconducting at high pressure and the Tc values of some elements has been found to increase dramatically under pressure. Though superficially the simplest of condensed matter systems, the elements exhibit surprising complexity when subjected to extreme compression. One of the exciting developments of the last two decades is that several elements have been found to become superconducting at temperatures near or above 20 K. The elements with the highest superconducting transition temperatures include Li (Tc ? 15- 20 K at 30 GPa [7-9]), Ca (Tc ? 21- 29 K at 220 GPa [10]), Sc [11] and Y [12] (Tc ? 20 K near 100 GPa), V (Tc ? 17 K at 120 GPa [13,14]), and S (Tc ? 17 K at 220 GPa [15]). These transition temperatures in pure elemental solids are especially remarkable considering the decades of research that went into developing the first superconducting compound with a Tc of 20 K [16].Fig. 1 presents an overview of the occurrence of superconductivity throughout the periodic table. At ambient pressure, 29 elements are superconducting (orange

  19. [High blood pressure in obese children and adolescents].

    PubMed

    Rascher, W; Kiess, W; Körner, A

    2013-04-01

    Obesity is also an important risk factor in children and adolescents for "essential" arterial hypertension, and contrary to what was assumed earlier, high blood pressure does cause damage to the cardiovascular system. As known from adults, elevated blood pressure induces cardiac hypertrophy, calcifications and atherosclerosis at the coronary vessels and thickens the small blood vessels. These early vascular alterations are particularly pronounced, when increased blood pressure is accompanied by other risk factors, such as dyslipidemia, hyperinsulinemia or smoking. As in any child with elevated blood pressure, the diagnostic evaluation should focus on confirmation of hypertension, determine if an underlying cause can be identified and whether hypertensive target organ damage is present. New reference office blood pressure values were recently published by a large representative community-based study in Germany. Therapy should begin with lifestyle modifications; however, antihypertensive medications will often be needed. Hypertension in obese adolescents occurs frequently and must be diagnosed and treated adequately. PMID:23529593

  20. Behavior of silver molybdate at high-pressure

    SciTech Connect

    Arora, A.K., E-mail: akarora49@yahoo.co.in [Condensed Matter Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Nithya, R. [Condensed Matter Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India)] [Condensed Matter Physics Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Misra, Sunasira [Liquid Metals and Structural Chemistry Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India)] [Liquid Metals and Structural Chemistry Division, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India); Yagi, Takehiko [Institute for Solid State Physics, Tokyo University, Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan)] [Institute for Solid State Physics, Tokyo University, Kashiwanoha, Kashiwa, Chiba 277-8581 (Japan)

    2012-12-15

    Behavior of cubic spinel phase of Ag{sub 2}MoO{sub 4} is investigated at high pressure using X-ray diffraction and Raman spectroscopy. The P-V data are fitted to a third order Birch-Murnaghan equation of state using a value of B{sub 0}=113 GPa and B Prime {sub 0}=4. The compound is also found to exhibit a phase transition around 5 GPa to a tetragonal structure and the two phases are found to coexist over a range of pressures. Raman spectra exhibit dramatic changes across the phase transition. Increase of X-ray background scattering and broadening of the Raman peaks associated with MoO{sub 4} tetrahedral ions in the high pressure phase suggest evolution of positional disorder. However, no evidence of pressure-induced amorphization was found up to 47 GPa. - Graphical abstract: Evolution of the integrated intensity of all the diffraction peaks between 12 and 18 degree 2{theta} as a function of pressure. The rapid decrease of the intensity suggests evolution of positional disorder in the high-pressure tetragonal phase. Highlights: Black-Right-Pointing-Pointer First in-situ X-ray diffraction and Raman study of cubic silver molybdate at high pressure. Black-Right-Pointing-Pointer Commencement of a structural transition to a tetragonal phase is found at 2.3 GPa. Black-Right-Pointing-Pointer The high-pressure phase is found to have positional disorder. Black-Right-Pointing-Pointer A bulk modulus of 113 GPa is obtained from the equation of state.

  1. A high-pressure carbon dioxide gasdynamic laser

    NASA Technical Reports Server (NTRS)

    Kuehn, D. M.

    1973-01-01

    A carbon dioxide gasdynamic laser was operated over a range of reservoir pressure and temperature, test-gas mixture, and nozzle geometry. A significant result is the dominant influence of nozzle geometry on laser power at high pressure. High reservoir pressure can be effectively utilized to increase laser power if nozzle geometry is chosen to efficiently freeze the test gas. Maximum power density increased from 3.3 W/cu cm of optical cavity volume for an inefficient nozzle to 83.4 W/cu cm at 115 atm for a more efficient nozzle. Variation in the composition of the test gas also caused large changes in laser power output. Most notable is the influence of the catalyst (helium or water vapor) that was used to depopulate the lower vibrational state of the carbon dioxide. Water caused an extreme deterioration of laser power at high pressure (100 atm), whereas, at low pressure the laser for the two catalysts approached similar values. It appears that at high pressure the depopulation of the upper laser level of the carbon dioxide by the water predominates over the lower state depopulation, thus destroying the inversion.

  2. Advanced High-Temperature, High-Pressure Transport Reactor Gasification

    SciTech Connect

    Michael L. Swanson

    2005-08-30

    The transport reactor development unit (TRDU) was modified to accommodate oxygen-blown operation in support of a Vision 21-type energy plex that could produce power, chemicals, and fuel. These modifications consisted of changing the loop seal design from a J-leg to an L-valve configuration, thereby increasing the mixing zone length and residence time. In addition, the standpipe, dipleg, and L-valve diameters were increased to reduce slugging caused by bubble formation in the lightly fluidized sections of the solid return legs. A seal pot was added to the bottom of the dipleg so that the level of solids in the standpipe could be operated independently of the dipleg return leg. A separate coal feed nozzle was added that could inject the coal upward into the outlet of the mixing zone, thereby precluding any chance of the fresh coal feed back-mixing into the oxidizing zone of the mixing zone; however, difficulties with this coal feed configuration led to a switch back to the original downward configuration. Instrumentation to measure and control the flow of oxygen and steam to the burner and mix zone ports was added to allow the TRDU to be operated under full oxygen-blown conditions. In total, ten test campaigns have been conducted under enriched-air or full oxygen-blown conditions. During these tests, 1515 hours of coal feed with 660 hours of air-blown gasification and 720 hours of enriched-air or oxygen-blown coal gasification were completed under this particular contract. During these tests, approximately 366 hours of operation with Wyodak, 123 hours with Navajo sub-bituminous coal, 143 hours with Illinois No. 6, 106 hours with SUFCo, 110 hours with Prater Creek, 48 hours with Calumet, and 134 hours with a Pittsburgh No. 8 bituminous coal were completed. In addition, 331 hours of operation on low-rank coals such as North Dakota lignite, Australian brown coal, and a 90:10 wt% mixture of lignite and wood waste were completed. Also included in these test campaigns was 50 hours of gasification on a petroleum coke from the Hunt Oil Refinery and an additional 73 hours of operation on a high-ash coal from India. Data from these tests indicate that while acceptable fuel gas heating value was achieved with these fuels, the transport gasifier performs better on the lower-rank feedstocks because of their higher char reactivity. Comparable carbon conversions have been achieved at similar oxygen/coal ratios for both air-blown and oxygen-blown operation for each fuel; however, carbon conversion was lower for the less reactive feedstocks. While separation of fines from the feed coals is not needed with this technology, some testing has suggested that feedstocks with higher levels of fines have resulted in reduced carbon conversion, presumably due to the inability of the finer carbon particles to be captured by the cyclones. These data show that these low-rank feedstocks provided similar fuel gas heating values; however, even among the high-reactivity low-rank coals, the carbon conversion did appear to be lower for the fuels (brown coal in particular) that contained a significant amount of fines. The fuel gas under oxygen-blown operation has been higher in hydrogen and carbon dioxide concentration since the higher steam injection rate promotes the water-gas shift reaction to produce more CO{sub 2} and H{sub 2} at the expense of the CO and water vapor. However, the high water and CO{sub 2} partial pressures have also significantly reduced the reaction of (Abstract truncated)

  3. Diamond anvil cell for spectroscopic investigation of materials at high temperature, high pressure and shear

    DOEpatents

    Westerfield, Curtis L. (Espanola, NM); Morris, John S. (Los Alamos, NM); Agnew, Stephen F. (Los Alamos, NM)

    1997-01-01

    Diamond anvil cell for spectroscopic investigation of materials at high temperature, high pressure and shear. A cell is described which, in combination with Fourier transform IR spectroscopy, permits the spectroscopic investigation of boundary layers under conditions of high temperature, high pressure and shear.

  4. A high pressure, high temperature study of 1,1-diamino-2,2-dinitro ethylene

    Microsoft Academic Search

    Michael Pravica; Martin Galley; Changyong Park; Harrison Ruiz; Jennifer Wojno

    2011-01-01

    We report a synchrotron energy-dispersive X-ray diffraction study of the novel high explosive 1,1-diamino-2,2-dinitroethylene at high pressures and high temperatures. Pressure was generated using a Paris–Edinburgh cell to employ larger sample volumes. High temperatures were created using a resistive graphite cylinder surrounding the sample. The PT phase diagram was explored in the 3.3 GPa pressure range and in the ? 400°C

  5. Microscopic Analysis of Bacterial Motility at High Pressure

    PubMed Central

    Nishiyama, Masayoshi; Sowa, Yoshiyuki

    2012-01-01

    The bacterial flagellar motor is a molecular machine that converts an ion flux to the rotation of a helical flagellar filament. Counterclockwise rotation of the filaments allows them to join in a bundle and propel the cell forward. Loss of motility can be caused by environmental factors such as temperature, pH, and solvation. Hydrostatic pressure is also a physical inhibitor of bacterial motility, but the detailed mechanism of this inhibition is still unknown. Here, we developed a high-pressure microscope that enables us to acquire high-resolution microscopic images, regardless of applied pressures. We also characterized the pressure dependence of the motility of swimming Escherichia coli cells and the rotation of single flagellar motors. The fraction and speed of swimming cells decreased with increased pressure. At 80 MPa, all cells stopped swimming and simply diffused in solution. After the release of pressure, most cells immediately recovered their initial motility. Direct observation of the motility of single flagellar motors revealed that at 80 MPa, the motors generate torque that should be sufficient to join rotating filaments in a bundle. The discrepancy in the behavior of free swimming cells and individual motors could be due to the applied pressure inhibiting the formation of rotating filament bundles that can propel the cell body in an aqueous environment. PMID:22768943

  6. Elasticity, strength, and refractive index of argon at high pressures

    NASA Astrophysics Data System (ADS)

    Chen, Bin; Gleason, A. E.; Yan, J. Y.; Koski, K. J.; Clark, Simon; Jeanloz, Raymond

    2010-04-01

    High-pressure Brillouin spectroscopy of polycrystalline argon, measured using two scattering angles ( 180° and 70° ), determines the isotropic elastic moduli, shear strength, equation of state, and refractive index of face-centered-cubic argon from 1.3 to 30 GPa at room temperature. The index of refraction n=1.33-1.67 over this pressure range. An Eulerian finite-strain analysis (Birch-Murnaghan equation of state) yields an isothermal bulk modulus and pressure derivative KT=15.1(±1.1)GPa and KT'=5.4(±0.3) at 2 GPa. The resulting equation of state agrees well with previous x-ray diffraction measurements, illustrating the suitability of high-pressure Brillouin scattering for characterizing the elasticity and strength of polycrystalline materials.

  7. High pressure intensification of cassava resistant starch (RS3) yields.

    PubMed

    Lertwanawatana, Proyphon; Frazier, Richard A; Niranjan, Keshavan

    2015-08-15

    Cassava starch, typically, has resistant starch type 3 (RS3) content of 2.4%. This paper shows that the RS3 yields can be substantially enhanced by debranching cassava starch using pullulanase followed by high pressure or cyclic high-pressure annealing. RS3 yield of 41.3% was obtained when annealing was carried out at 400MPa/60°C for 15 min, whereas it took nearly 8h to obtain the same yield under conventional atmospheric annealing at 60°C. The yield of RS3 could be further significantly increased by annealing under 400 MPa/60°C pressure for 15 min followed by resting at atmospheric pressure for 3h 45 min, and repeating this cycle for up to six times. Microstructural surface analysis of the product under a scanning electron microscope showed an increasingly rigid density of the crystalline structure formed, confirming higher RS3 content. PMID:25794725

  8. Amorphous Diamond: A High-Pressure Superhard Carbon Allotrope

    SciTech Connect

    Lin, Yu; Zhang, Li; Mao, Ho-kwang; Chow, Paul; Xiao, Yuming; Baldini, Maria; Shu, Jinfu; Mao, Wendy L. (Stanford); (CIW)

    2011-12-09

    Compressing glassy carbon above 40 GPa, we have observed a new carbon allotrope with a fully sp{sup 3}-bonded amorphous structure and diamondlike strength. Synchrotron x-ray Raman spectroscopy revealed a continuous pressure-induced sp{sup 2}-to-sp{sup 3} bonding change, while x-ray diffraction confirmed the perseverance of noncrystallinity. The transition was reversible upon releasing pressure. Used as an indenter, the glassy carbon ball demonstrated exceptional strength by reaching 130 GPa with a confining pressure of 60 GPa. Such an extremely large stress difference of >70 GPa has never been observed in any material besides diamond, indicating the high hardness of this high-pressure carbon allotrope.

  9. High pressure sample cell for total internal reflection fluorescence spectroscopy at pressures up to 2500 bar.

    PubMed

    Koo, Juny; Czeslik, Claus

    2012-08-01

    Total internal reflection fluorescence (TIRF) spectroscopy is a surface sensitive technique that is widely used to characterize the structure and dynamics of molecules at planar liquid-solid interfaces. In particular, biomolecular systems, such as protein adsorbates and lipid membranes can easily be studied by TIRF spectroscopy. Applying pressure to molecular systems offers access to all kinds of volume changes occurring during assembly of molecules, phase transitions, and chemical reactions. So far, most of these volume changes have been characterized in bulk solution, only. Here, we describe the design and performance of a high pressure sample cell that allows for TIRF spectroscopy under high pressures up to 2500 bar (2.5 × 10(8) Pa), in order to expand the understanding of volume effects from the bulk phase to liquid-solid interfaces. The new sample cell is based on a cylindrical body made of Nimonic 90 alloy and incorporates a pressure transmitting sample cuvette. This cuvette is composed of a fused silica prism and a flexible rubber gasket. It contains the sample solution and ensures a complete separation of the sample from the liquid pressure medium. The sample solution is in contact with the inner wall of the prism forming the interface under study, where fluorescent molecules are immobilized. In this way, the new high pressure TIRF sample cell is very useful for studying any biomolecular layer that can be deposited at a planar water-silica interface. As examples, high pressure TIRF data of adsorbed lysozyme and two phospholipid membranes are presented. PMID:22938334

  10. Moissanite: A Window for High-Pressure Experiments

    NASA Astrophysics Data System (ADS)

    Xu, Ji-an; Mao, Ho-kwang

    2000-10-01

    We achieved a pressure of 52.1 gigapascals with moissanite anvils, which have optical, thermal, electric, magnetic, and x-ray properties that rival those of diamond. The mode-softening of D2O toward the pressure-induced hydrogen bond symmetrization and the Raman shifts of diamond under hydrostatic and nonhydrostatic compressions were studied with moissanite anvils in the spectral regions normally obscured by diamond anvils. Moissanite anvil cells allow maximum sample volumes 1000 times larger than those allowed by diamond anvil cells and may enable the next level of advancement in high-pressure experiments.

  11. Moissanite: a window for high-pressure experiments.

    PubMed

    Xu, J; Mao, H

    2000-10-27

    We achieved a pressure of 52.1 gigapascals with moissanite anvils, which have optical, thermal, electric, magnetic, and x-ray properties that rival those of diamond. The mode-softening of D(2)O toward the pressure-induced hydrogen bond symmetrization and the Raman shifts of diamond under hydrostatic and nonhydrostatic compressions were studied with moissanite anvils in the spectral regions normally obscured by diamond anvils. Moissanite anvil cells allow maximum sample volumes 1000 times larger than those allowed by diamond anvil cells and may enable the next level of advancement in high-pressure experiments. PMID:11052937

  12. LOX vaporization in high-pressure, hydrogen-rich gas

    NASA Technical Reports Server (NTRS)

    Litchford, Ron J.; Jeng, San-Mou

    1990-01-01

    LOX droplet vaporization in high-pressure hydrogen-rich gas is analyzed, with special attention to thermodynamic effects which compel the surface to heat to the critical state and to supercritical vaporization processes on heating to criticality. Subcritical vaporization is modeled using a quasi-steady diffusion-controlled gas-phase transport formulation coupled to an effective-conductivity internal-energy-transport model accounting for circulation effects. It is demonstrated how the droplet surface might heat to the critical state, for ambient pressures slightly greater than the critical pressure of oxygen, such that the bulk of propellant within the droplet remains substantially below the critical mixing temperature.

  13. High pressure melting curves of silver, gold and copper

    SciTech Connect

    Hieu, Ho Khac, E-mail: hieuhk@duytan.edu.vn [Research and Development Center for Science and Technology, Duy Tan University, K7/25 Quang Trung, Danang (Viet Nam); Ha, Nguyen Ngoc [VNU-Hanoi University of Science, 334 Nguyen Trai, Hanoi (Viet Nam)] [VNU-Hanoi University of Science, 334 Nguyen Trai, Hanoi (Viet Nam)

    2013-11-15

    In this work, based on the Lindemann's formula of melting and the pressure-dependent Grüneisen parameter, we have investigated the pressure effect on melting temperature of silver, gold and copper metals. The analytical expression of melting temperature as a function of volume compression has been derived. Our results are compared with available experimental data as well as with previous theoretical studies and the good and reasonable agreements are found. We also proposed the potential of this approach on predicting melting of copper at very high pressure.

  14. Structural Behaviour of Uranium Sulfide under High Pressure

    SciTech Connect

    Shareef, F.; Singh, S.; Gour, A.; Bhardwaj, P.; Sarwan, M.; Dubey, R. [High Pressure Research Lab, Department of Physics, Barkatullah University, Bhopal-462026 (India); Singh, R. K. [ITM University, Gurgaon, Haryana-122017 (India)

    2011-07-15

    The study of pressure induced structural phase transition of uranium sulphide, which crystallizes in rock salt (B1) structure, has been performed using the well described three body interaction model (TBIPM). Our present TBIP model consists of long range coulombic interaction, three body interactions, Hafemeister and Flygare type short-range overlap repulsion extended upto the second neighbor ions and the van der Waals interaction. The present results are in good agreement with the available experimental data on the phase transition pressure (Pt = 80.2 GPa). So it can be considered as an adequate and suitable model to perform high pressure studies.

  15. Magnetic Collapse in Transition Metals Oxides at High Pressures

    Microsoft Academic Search

    R. E. Cohen; I. I. Mazin; D. G. Isaak

    1997-01-01

    We predict magnetic collapse (i.e. high-spin low-spin transitions) in transition metal ions using LMTO-ASA and LAPW methods and the GGA. Magnetic collapse under pressure results from band widening, rather than from changes in crystal field splitting. We find that the extended Stoner model is accurate in predicting the magnetic moments and transition pressures compared with our self-consistent calculations. The GGA

  16. Effect of high pressure on the emulsifying behaviour of ?-lactoglobulin

    Microsoft Academic Search

    Vanda B. Galazka; Eric Dickinson; Dave A. Ledward

    1996-01-01

    The influence of high pressure (up to 800 MPa) on the emulsifying behaviour of ?-lactoglobulin has been investigated at neutral pH. Fine oil-in-water emulsions (0.4% w\\/w ?-lactoglobulin, 20% v\\/v oil) made with the pressure-treated protein were found to give substantially larger droplets than those made with the native protein. Visual creaming behaviour and changes in average droplet size have been

  17. Titanium-based Laves phase hydrides with high dissociation pressure

    Microsoft Academic Search

    S. V. Mitrokhin; V. N. Verbetsky

    1997-01-01

    The results of the investigation of the hydrogen interaction with Laves phases having general composition Ti1 ? xZrxMn2 ? y ? zCryFez are presented. The hydride phases are characterized by the rather high dissociation pressure of hydrogen at ambient temperature. The experiments were staged in standard Sieverts apparatus at pressures up to 100 atm and in a special apparatus which

  18. Crystal Plasticity for Dynamic Loading at High Pressures and Strains

    Microsoft Academic Search

    Damian C. Swift; Eric N. Loomis; Pedro Peralta; Bassem El-Dasher

    2007-01-01

    A crystal plasticity theory was developed for use in simulations of dynamic loading at high pressures and strain rates. At pressures of the order of the bulk modulus, compressions o(100%) may be induced. At strain rates o(10^9)\\/s or higher, elastic strains may reach o(10%), which may change the orientation of the slip systems significantly with respect to the stress field.

  19. Patellofemoral contact pressure following high tibial osteotomy: a cadaveric study

    Microsoft Academic Search

    Karl Stoffel; Craig Willers; Omar Korshid; Markus Kuster

    2007-01-01

    Patella infera is a known complication of high tibial osteotomy (HTO) that can cause anterior knee pain due to excessive stresses\\u000a associated with abnormal patellofemoral (PF) joint biomechanics. However, the translation of these abnormal biomechanics to\\u000a native cartilage pressure has not been explored. The present study was designed to compare the PF contact pressures of three\\u000a different HTOs in a

  20. A System for Incubations at High Gas Partial Pressure

    PubMed Central

    Sauer, Patrick; Glombitza, Clemens; Kallmeyer, Jens

    2012-01-01

    High-pressure is a key feature of deep subsurface environments. High partial pressure of dissolved gasses plays an important role in microbial metabolism, because thermodynamic feasibility of many reactions depends on the concentration of reactants. For gases, this is controlled by their partial pressure, which can exceed 1?MPa at in situ conditions. Therefore, high hydrostatic pressure alone is not sufficient to recreate true deep subsurface in situ conditions, but the partial pressure of dissolved gasses has to be controlled as well. We developed an incubation system that allows for incubations at hydrostatic pressure up to 60?MPa, temperatures up to 120°C, and at high gas partial pressure. The composition and partial pressure of gasses can be manipulated during the experiment. To keep costs low, the system is mainly made from off-the-shelf components with only very few custom-made parts. A flexible and inert PVDF (polyvinylidene fluoride) incubator sleeve, which is almost impermeable for gases, holds the sample and separates it from the pressure fluid. The flexibility of the incubator sleeve allows for sub-sampling of the medium without loss of pressure. Experiments can be run in both static and flow-through mode. The incubation system described here is usable for versatile purposes, not only the incubation of microorganisms and determination of growth rates, but also for chemical degradation or extraction experiments under high gas saturation, e.g., fluid–gas–rock-interactions in relation to carbon dioxide sequestration. As an application of the system we extracted organic compounds from sub-bituminous coal using H2O as well as a H2O–CO2 mixture at elevated temperature (90°C) and pressure (5?MPa). Subsamples were taken at different time points during the incubation and analyzed by ion chromatography. Furthermore we demonstrated the applicability of the system for studies of microbial activity, using samples from the Isis mud volcano. We could detect an increase in sulfate reduction rate upon the addition of methane to the sample. PMID:22347218

  1. High Pressures and Preserving the Records of Life.

    NASA Astrophysics Data System (ADS)

    Montgomery, W.; Watson, J. S.; Sephton, M. A.

    2014-12-01

    The passage of organic matter from Earth's surface ecosystems to the geological record is marked by the loss of certain classes of organic compounds and the transformation of those classes which are preserved. Much effort has been expended to understand the effects of temperature on buried organic matter. It is thought that heat may destroy certain organic structures and help to polymerize others into oligomers and polymers with a high preservation potential. The consequences of pressure remain less well understood. The neglect of pressure as a transforming agent is surprising considering the proliferation of high-pressure environments on Earth and beyond. We have performed in situ high pressure synchrotron-source FTIR spectroscopy measurements on standards representing common units found within kerogens. These standards represent the aliphatic, aromatic and polar components of natural organic matter in monomeric and polymeric forms. Samples were taken to 11 GPa at ambient temperature; some were also heated to their melting point at <2 GPa. Heated large volume press experiments have allowed quantitative analysis of natural samples: Type I and II kerogens are inherently unstable under pressure, Type III and IV kerogens are more stable. Our diamond anvil cell measurements open a window onto the effects of pressure on individual classes of organic compounds, with consequences for the transformation and preservation of organic matter in the subsurface.

  2. Plasma interferometry at high pressures Kamran Akhtar,a)

    E-print Network

    Scharer, John E.

    millimeter wave interferometry is presented. In the presence of high density and collisionality at high gas plasma density accurately over wide plasma density and gas pressure ranges. Interferometry is primarily of the millimeter wave ( , p), the measured line-average plasma density has a complex dependence on phase shift

  3. INFRARED SPECTROSCOPY OF CONJUGATED ORGANIC MOLECULES UNDER HIGH PRESSURE

    E-print Network

    Collins, Gary S.

    INFRARED SPECTROSCOPY OF CONJUGATED ORGANIC MOLECULES UNDER HIGH PRESSURE By KIRILL KHAMIDOVICH with germanium detectors. Brooke Bafus work on taking p-quaterphenyl spectra was very supportive and Slade Jokela's help with the vapor deposition system is extremely highly appreciated. I personally want to thank my

  4. High-temperature fiber optic cubic-zirconia pressure sensor

    Microsoft Academic Search

    Wei Peng; Gary R. Pickrell; Anbo Wang

    2005-01-01

    There is a critical need for pressure sensors that can operate reliably at high temperatures in many industrial segments such as in the combustion section of gas turbine engines for both transportation and power generation, coal gasifiers, coal fired boilers, etc. Optical-based sensors are particularly attractive for the measurement of a wide variety of physical and chemical parameters in high-temperature

  5. Vacuum assisted high pressure die casting of aluminium alloys

    Microsoft Academic Search

    X. P. Niu; B. H. Hu; I. Pinwill; H. Li

    2000-01-01

    High pressure die castings usually contain gas porosity due mainly to the entrapment of air or gas in the melt during the very high speed injection of the molten metal into the cavity. In this paper, the advantages of using an evacuated die cavity during mould filling were evaluated. ASTM standard die casting tensile specimens of three Al alloys, Al–5%Si,

  6. Surprisingly high pressure shocks in the supernova remnant IC443

    E-print Network

    Burton, Michael

    Surprisingly high pressure shocks in the supernova remnant IC443 A. Moorhouse, 1 P.W.J.L. Brand, 1/molecular cloud shock in IC443. The lines measured have upper state energies ranging from 7000 K to 23000 K Introduction Observations of high velocity neutral atomic hydrogen in the supernova remnant (SNR) IC443 by (De

  7. 21 CFR 862.2260 - High pressure liquid chromatography system for clinical use.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...862.2260 High pressure liquid chromatography system for clinical...Identification. A high pressure liquid chromatography system for...influence of a high pressure liquid (mobile phase). Separation of the solutes occurs...

  8. 21 CFR 862.2260 - High pressure liquid chromatography system for clinical use.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...862.2260 High pressure liquid chromatography system for clinical...Identification. A high pressure liquid chromatography system for...influence of a high pressure liquid (mobile phase). Separation of the solutes occurs...

  9. 21 CFR 862.2260 - High pressure liquid chromatography system for clinical use.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...862.2260 High pressure liquid chromatography system for clinical...Identification. A high pressure liquid chromatography system for...influence of a high pressure liquid (mobile phase). Separation of the solutes occurs...

  10. Collision condition indicted by High Pressure Phases in a Chondrite

    NASA Astrophysics Data System (ADS)

    Kato, Y.; Sekine, T.; Kayama, M.; Miyahara, M.; Yamaguchi, A.

    2012-12-01

    It has been generally recognized that there were many collisions during planetary accretion. Chondrites include the materials at the time of formation of the solar system. It is essential to unravel the shock history in meteorites and the parent planet in order to understand such collisional processes. In this study, we investigate a thin section of ordinary chondrite Y-790729 classified as L6 in which high-pressure minerals are found in the about 620-?m-wide shock vein. The mineralogical and chemical features give us detailed information to constrain the shock conditions. We have tried to constrain the P-T condition from the viewpoints of the mineral assemblage and cathodoluminescense (CL) spectroscopy. Y-790729 consists mostly of olivine and pyroxene and has shock veins. To identify high pressure phases, we used an optical microscope, a scanning electron microscope (SEM), micro Raman spectroscopy, and electron probe micro analyzer (EPMA). In addition, scanning electron microscopy-cathodoluminescence (SEM-CL) analysis, detectable shock-induced defect centers, was used to characterize the shock metamorphism in feldspar minerals. The presence of shock vein, maskelynite, and high pressure phases confirms shock record. 7 high pressure phases of ringwoodite, high-pressure clinoenstatite (HPC), majorite, merrillite, lingunite, high-pressure chromite and akimotoite were found in this section. All of them exist only in a shock vein, but maskelynite occurs everywhere in the section. From these observations, it is obvious that the shock vein experienced the high pressure and high temperature generated by shock wave. If some of the high pressure minerals are equilibrated, the P-T condition can be estimated. Based on the equilibrium phase diagram of MgSiO3 polymorphs (Presnall. 1995), the P-T conditions for crystallization of majorite, HPC and akimotoite is about 17 GPa and 1600 oC, because the compositions of the three phases are close to MgSiO3. It is consistent with the stability fields for ringwoodite, merrillite and diopside. Employing the shock properties of an ordinary chondrite (F. Zhang and T. Sekine, 2007) and the impedance match method, an impact velocity of 1.74 km/s is obtained for a symmetrical head-on impact. CL spectroscopy of experimentally shocked sanidine gives us a linear correlation between integral intensity of emission components at 2.948 eV and the applied peak shock pressure. Then, a pressure over 15 GPa can be estimated based on these relationships and the intensities at 2.948 eV derived from maskelynite in Y-790729, covering the value estimated from the high pressure phase assemblage. We plan to investigate the detailed microstructures and the particle sizes of the high pressure minerals in the shock vein by transmission electron microscope (TEM). By examining minerals in the shock vein in detail, it is expected that the formation mechanism of the high pressure phases will be understood and that the collisional process will be unraveled from the material evolution. In addition, the shock duration, the parent body size, and the time required for the crystal growth need to be estimated as further development.

  11. Advanced Synchrotron Techniques at High Pressure Collaborative Access Team (HPCAT)

    NASA Astrophysics Data System (ADS)

    Shen, G.; Sinogeikin, S. V.; Chow, P.; Kono, Y.; Meng, Y.; Park, C.; Popov, D.; Rod, E.; Smith, J.; Xiao, Y.; Mao, H.

    2012-12-01

    High Pressure Collaborative Access Team (HPCAT) is dedicated to advancing cutting-edge, multidisciplinary, high-pressure science and technology using synchrotron radiation at Sector 16 of the Advanced Photon Source (APS) of Argonne National Laboratory. At HPCAT an array of novel x-ray diffraction and spectroscopic techniques has been integrated with high pressure and extreme temperature instrumentation for studies of structure and materials properties at extreme conditions.. HPCAT consists of four active independent beamlines performing a large range of various experiments at extreme conditions. 16BM-B beamline is dedicated to energy dispersive and white Laue X-ray diffraction. The majority of experiments are performed with a Paris-Edinburgh large volume press (to 7GPa and 2500K) and include amorphous and liquid structure measurement, white beam radiography, elastic sound wave velocity measurement of amorphous solid materials, with viscosity and density measurement of liquid being under development. 16BM-D is a monochromatic diffraction beamline for powder and single crystal diffraction at high pressure and high (resistive heating) / low (cryostats) temperature. The additional capabilities include high-resolution powder diffraction and x-ray absorption near edge structure (XANES) spectroscopy. The insertion device beamline of HPCAT has two undulators in canted mode (operating independently) and LN cooled Si monochromators capable of providing a large range of energies. 16IDB is a microdiffraction beamline mainly focusing on high-pressure powder and single crystal diffraction in DAC at high temperatures (double-sided laser heating and resistive heating) and low temperature (various cryostats). The modern instrumentation allows high-quality diffraction at megabar pressures from light element, fast experiments with pulsed laser heating, fast dynamic experiments with Pilatus detector, and so on. 16ID-D beamline is dedicated to x-ray scattering and spectroscopy research of materials under high pressure in DAC. The available techniques include nuclear forward scattering, nuclear resonant inelastic scattering with 2meV energy resolution for determining phonon density of state and Mössbauer effect, x-ray inelastic scattering (X-ray Raman) with 1eV energy resolution for the study of charge dynamics and chemical bonding, x-ray spectroscopy for the study of electronic excitations, X-ray emission (including partial fluorescence yield, resonant emission). Many of these measurements can be done at low temperature, with in-situ pressure measurement, or at high temperature with portable laser heating. All these advanced synchrotron techniques, as well as supporting facilities, employed at HPCAT, will be discussed.

  12. A novel high pressure, high temperature vessel used to conduct long-term stability measurements of silicon MEMS pressure transducers

    NASA Astrophysics Data System (ADS)

    Wisniewiski, David

    2014-03-01

    The need to quantify and to improve long-term stability of pressure transducers is a persistent requirement from the aerospace sector. Specifically, the incorporation of real-time pressure monitoring in aircraft landing gear, as exemplified in Tire Pressure Monitoring Systems (TPMS), has placed greater demand on the pressure transducer for improved performance and increased reliability which is manifested in low lifecycle cost and minimal maintenance downtime through fuel savings and increased life of the tire. Piezoresistive (PR) silicon MEMS pressure transducers are the primary choice as a transduction method for this measurement owing to their ability to be designed for the harsh environment seen in aircraft landing gear. However, these pressure transducers are only as valuable as the long-term stability they possess to ensure reliable, real-time monitoring over tens of years. The "heart" of the pressure transducer is the silicon MEMS element, and it is at this basic level where the long-term stability is established and needs to be quantified. A novel High Pressure, High Temperature (HPHT) vessel has been designed and constructed to facilitate this critical measurement of the silicon MEMS element directly through a process of mechanically "floating" the silicon MEMS element while being subjected to the extreme environments of pressure and temperature, simultaneously. Furthermore, the HPHT vessel is scalable to permit up to fifty specimens to be tested at one time to provide a statistically significant data population on which to draw reasonable conclusions on long-term stability. With the knowledge gained on the silicon MEMS element, higher level assembly to the pressure transducer envelope package can also be quantified as to the build-effects contribution to long-term stability in the same HPHT vessel due to its accommodating size. Accordingly, a HPHT vessel offering multiple levels of configurability and robustness in data measurement is presented, along with 10 year long-term stability results.

  13. High-Pressure Phase Transition in Yttrium Iron Garnet

    NASA Astrophysics Data System (ADS)

    Stan, C. V.; Wang, J.; Zouboulis, I. S.; Prakapenka, V.; Duffy, T. S.

    2014-12-01

    High-pressure investigations of rare earth transition metal oxide garnets have revealed structural and magnetic phase transitions, including pressure-induced amorphization, magnetic collapse, spin crossover transitions and metallization, as well as transformation to highly-incompressible oxides. Yttrium iron garnet (YIG), Y3Fe5O12, exhibits interesting magnetic properties, behaving as a ferrimagnet with a Néel temperature TN ~ 559 K at ambient pressure and transforming to a paramagnetic material at high temperatures. At high temperatures and pressures, it converts to a GdFeO3-type perovskite structure. However, the composition of the perovskite is debated, with two proposed reaction pathways, leading to either (Y0.75Fe0.25)FeO3-perovskite or a mixture of YFeO3-perovskite and Fe2O3. Here, we synthesized YIG-perovskite in the diamond anvil cell above 18 GPa and 1500 K at GeoSoilEnviroCARS beamline 13-ID-D of the Advanced Photon Source. NaCl was used as a quasihydrostatic pressure medium, and Au, with the Fei equation of state, was used as the pressure calibrant and laser absorber. Our measurements of the perovskite structure extend to 70 GPa with annealing at each pressure step. We do not find any iron oxide diffraction peaks after heating, indicating that the perovskite structure is likely (Y0.75Fe0.25)FeO3. We observe a previously unknown ~5% volume discontinuity in the perovskite between 44 and 50 GPa. This discontinuity is not accompanied by a change in the diffraction pattern, suggesting that the Fe in this structure undergoes a high-spin to low-spin transition. When compressing without laser heating, we confirm the amorphization of YIG starting material at 50 GPa that was previously observed by Gavriliuk et al. (2006). This amorphous material is easily converted to the low-spin perovskite upon heating above 1400 K.

  14. High pressure generation using scaled-up Kawai-cell

    NASA Astrophysics Data System (ADS)

    Shatskiy, A.; Katsura, T.; Litasov, K. D.; Shcherbakova, A. V.; Borzdov, Y. M.; Yamazaki, D.; Yoneda, A.; Ohtani, E.; Ito, E.

    2011-11-01

    A scaled-up version of a 6-8 Kawai-type multianvil apparatus equipped with 47-mm WC anvils has been developed at the Institute for the Study of the Earth's Interior for operation over pressure ranging up to 19 and 24 GPa using the conventional system with larger compressional volumes between 1.2 and 0.4 cm 3, respectively. This system is used under uniaxial compression along cube diagonal of the Kawai-cell up to the press load of 19 MN. Experiments are performed using octahedral pressure media (PM) made of MgO- and ZrO 2-based semi-sintered ceramics and unfired pyrophyllite gaskets. In this study we used "Toshiba-F" grade WC anvils allowing pressure generation up to 24 GPa. We perform pressure calibrations at room and high temperatures, with octahedron/anvil truncation edge-length ratios ( a0/ b, mm) of 12.2/6, 14/6, 14/7, 16/7, 18/7, 18/9, and 18/10. Different configurations show that an increase in edge-length ratio of a0/b permits the achievement of higher pressure, which agrees with the results of Frost at al. (Frost, D.J., Poe, B.T., Tronnes, R.G., Liebske, C., Duba, A., Rubie, D.C., 2004. A new large-volume multianvil system. Phys. Earth Planet. Inter. 143, 507). However, it also shifts the pressure maximum to higher press loads, in some cases exceeding the capacity of a press. Our and Frost et al. (2004) data reveal that the 14/6, 18/8, and 18/10 assemblies are the most suitable in generating pressures of up to 19-24 GPa at 19 MN press load limits. The assemblies with a low a0/ b ratio have a lower upper pressure limit; however, they exhibit a systematically higher efficiency in pressure generation at low press loads. Consequently, assemblages with high and low a0/ b ratios should be used in high and low pressure experiments, respectively. For example, the 18/12 assembly is suitable for 5-11 GPa pressure range (Stoyanov, E., Haussermann, U., Leinenweber, K., 2010. Large-volume multianvil cells designed for chemical synthesis at high pressures. High Pressure Res., 30, 175), whereas the 14/6, 18/8 ( Frost et al., 2004), and 18/10 assemblies are suitable for 22-24, 19-23, and 11-19 GPa pressure ranges, respectively. The maximum pressure generation achieved in the present study is 24 GPa, using the 14/6 assembly. This appears to be the maximum pressure level attainable by using WC anvils.

  15. HIGH TEMPERATURE HIGH PRESSURE THERMODYNAMIC MEASUREMENTS FOR COAL MODEL COMPOUNDS

    SciTech Connect

    Vinayak N. Kabadi

    1999-02-24

    The enthalpy of a fluid measured with respect to some reference temperature and pressure (enthalpy increment or Cp) is required for many engineering designs. Different techniques for determining enthalpy increments include direct measurement, integration of heat capacity as a function of temperature at constant pressure, and calculation from accurate density measurements as a function of temperature and pressure with ideal-gas enthalpies. Techniques have been developed for measurement of heat capacities using differential scanning calorimeters, but routine measurements with a precision better than 3% are rare. For thermodynamic model development, excess enthalpies or enthalpies of mixing of binary and ternary systems are generally required. Although these data can be calculated from measured values of incremental enthalpies of mixtures and corresponding pure components, the method of calculation involves subtraction of large numbers, and it is impossible to obtain accurate results from relatively accurate incremental enthalpy data. Directly measured heats of mixing provide better data for model development. In what follows, we give a brief literature survey of experimental methods available for measurement of incremental enthalpies as well as heats of mixing.

  16. Unsteady pressure loads in a generic high speed engine model

    NASA Technical Reports Server (NTRS)

    Parrott, Tony L.; Jones, Michael G.; Thurlow, Ernie M.

    1992-01-01

    Unsteady pressure loads were measured along the top interior wall of a generic high-speed engine (GHSE) model undergoing performance tests in the combustion-Heated Scramjet Test Facility at the Langley Research Center. Flow to the model inlet was simulated at 72000 ft and a flight Mach number of 4. The inlet Mach number was 3.5 with a total temperature and pressure of 1640 R and 92 psia. The unsteady pressure loads were measured with 5 piezoresistive gages, recessed into the wall 4 to 12 gage diameters to reduce incident heat flux to the diaphragms, and distributed from the inlet to the combustor. Contributors to the unsteady pressure loads included boundary layer turbulence, combustion noise, and transients generated by unstart loads. Typical turbulent boundary layer rms pressures in the inlet ranged from 133 dB in the inlet to 181 dB in the combustor over the frequency range from 0 to 5 kHz. Downstream of the inlet exist, combustion noise was shown to dominate boundary layer turbulence noise at increased heat release rates. Noise levels in the isolator section increased by 15 dB when the fuel-air ratio was increased from 0.37 to 0.57 of the stoichiometric ratio. Transient pressure disturbances associated with engine unstarts were measured in the inlet and have an upstream propagation speed of about 7 ft/sec and pressure jumps of at least 3 psia.

  17. Ultra-high pressure water jet: Baseline report

    SciTech Connect

    NONE

    1997-07-31

    The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky{trademark} pump feeds water to a lance that directs the high pressure water at the surface to be removed. The safety and health evaluation during the testing demonstration focused on two main areas of exposure. These were dust and noise. The dust exposure was found to be minimal, which would be expected due to the wet environment inherent in the technology, but noise exposure was at a significant level. Further testing for noise is recommended because of the outdoor environment where the testing demonstration took place. In addition, other areas of concern found were arm-hand vibration, ergonomics, heat stress, tripping hazards, electrical hazards, lockout/tagout, fall hazards, slipping hazards, hazards associated with the high pressure water, and hazards associated with air pressure systems.

  18. A high pressure modulated molecular beam mass spectrometric sampling system

    NASA Technical Reports Server (NTRS)

    Stearns, C. A.; Kohl, F. J.; Fryburg, G. C.; Miller, R. A.

    1977-01-01

    The current state of understanding of free-jet high pressure sampling is critically reviewed and modifications of certain theoretical and empirical considerations are presented. A high pressure, free-jet expansion, modulated molecular beam, mass spectrometric sampling apparatus was constructed and this apparatus is described in detail. Experimental studies have demonstrated that the apparatus can be used to sample high temperature systems at pressures up to one atmosphere. Condensible high temperature gaseous species have been routinely sampled and the mass spectrometric detector has provided direct identification of sampled species. System sensitivity is better than one tenth of a part per million. Experimental results obtained with argon and nitrogen beams are presented and compared to theoretical predictions. These results and the respective comparison are taken to indicate acceptable performance of the sampling apparatus. Results are also given for two groups of experiments related to hot corrosion studies. The formation of gaseous sodium sulfate in doped methane-oxygen flames was characterized and the oxidative vaporization of metals was studied in an atmospheric pressure flowing gas system to which gaseous salt partial pressures were added.

  19. High-pressure RF cavities for muon beam cooling

    NASA Astrophysics Data System (ADS)

    Yonehara, K.; Alsharo'a, M.; Ankenbrandt, C. M.; Hartline, R. E.; Johnson, R. P.; Kaplan, D. M.; Kuchnir, M.; Moretti, A.; Popovic, M.

    2005-12-01

    An 800 MHz RF test cell filled with high pressure gaseous hydrogen was used to study RF breakdown phenomena in hydrogen and helium gases as a function of pressure and temperature. The maximum achieved RF surface gradient was 80 MV/m at 1.83 MPa and 77 K, where the breakdown of the molybdenum electrodes of the test cell limited the study of the linear dependence of the breakdown voltage on gas density known as Paschen's Law. The test cell conditioning was also much faster in gas than in vacuum cavities. The high gradient and fast conditioning are encouraging results for the use of high-pressure RF cavities for ionization cooling of muon beams for muon colliders, neutrino factories, and intense sources.

  20. Ultra-high pressure water jet: Baseline report; Greenbook (chapter)

    SciTech Connect

    NONE

    1997-07-31

    The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky{trademark} pump feeds water to a lance that directs the high pressure water at the surface to be removed. The technologies being tested for concrete decontamination are targeted for alpha contamination. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

  1. High-pressure layered structure of carbon disulfide

    NASA Astrophysics Data System (ADS)

    Naghavi, S. Shahab; Crespo, Yanier; MartoÅák, Roman; Tosatti, Erio

    2015-06-01

    Solid CS2 is superficially similar to CO2, with the same C m c a molecular crystal structure at low pressures, which has suggested similar phases also at high pressures. We carried out an extensive first-principles evolutionary search in order to identify the zero-temperature lowest-enthalpy structures of CS2 for increasing pressure up to 200 GPa. Surprisingly, the molecular C m c a phase does not evolve into ? -cristobalite as in CO2 but transforms instead into phases HP2 and HP1, both recently described in high-pressure SiS2. HP1 in particular, with a wide stability range, is a layered P 21/c structure characterized by pairs of edge-sharing tetrahedra and is theoretically more robust than all other CS2 phases discussed so far. Its predicted Raman spectrum and pair correlation function agree with experiment better than those of ? -cristobalite, and further differences are predicted between their respective IR spectra. The band gap of HP1-CS2 is calculated to close under pressure, yielding an insulator-metal transition near 50 GPa, in agreement with experimental observations. However, the metallic density of states remains modest above this pressure, suggesting a different origin for the reported superconductivity.

  2. Exploring the high-pressure behavior of superhard tungsten tetraboride

    NASA Astrophysics Data System (ADS)

    Xie, Miao; Mohammadi, Reza; Mao, Zhu; Armentrout, Matt M.; Kavner, Abby; Kaner, Richard B.; Tolbert, Sarah H.

    2012-02-01

    In this work, we examine the high-pressure behavior of superhard material candidate WB4 using high-pressure synchrotron x-ray diffraction in a diamond anvil cell up to 58.4 GPa. The zero-pressure bulk modulus, K0, obtained from fitting the pressure-volume data using the second-order Birch-Murnaghan equation of state is 326 ± 3 GPa. A reversible, discontinuous change in slope in the c/a ratio is further observed at ˜42 GPa, suggesting that lattice softening occurs in the c direction above this pressure. This softening is not observed in other superhard transition metal borides such as ReB2 compressed to similar pressures. Speculation on the possible relationship between this softening and the orientation of boron-boron bonds in the c direction in the WB4 structure is included. Finally, the shear and Young's modulus values are calculated using an isotropic model based on the measured bulk modulus and an estimated Poisson's ratio for WB4.

  3. Metallic conductivity of amorphous carbon films under high pressure

    SciTech Connect

    Bhattacharyya, S.; Subramanyam, S.V. [Department of Physics, Indian Institute of Science, Bangalore 560012 (India)] [Department of Physics, Indian Institute of Science, Bangalore 560012 (India)

    1997-08-01

    Amorphous carbon films are prepared by plasma-assisted chemical vapor deposition. Resistivity of the films is measured from 300 down to 8 K showing a negative temperature coefficient of resistivity. An increase of room temperature conductivity from 10{sup 2} Scm{sup {minus}1} to a value of about 10{sup 4} Scm{sup {minus}1} is found at a pressure of 2 GPa. At a fixed pressure of 0.5 GPa, the films show a positive temperature coefficient of conductivity in the range from 300 to 200 K, followed by a very weak dependence of temperature down to 15 K. At a pressure of 2 GPa a positive temperature coefficient of resistivity is observed in the range between 300 and 15 K. The metallic behavior of the carbon films under high pressure is explained using electronic structure. {copyright} {ital 1997 American Institute of Physics.}

  4. High-pressure Raman spectroscopy of phase change materials

    SciTech Connect

    Hsieh, Wen-Pin, E-mail: wphsieh@stanford.edu; Mao, Wendy L. [SLAC National Accelerator Laboratory, Stanford Institute for Materials and Energy Sciences, Menlo Park, California 94025 (United States) [SLAC National Accelerator Laboratory, Stanford Institute for Materials and Energy Sciences, Menlo Park, California 94025 (United States); Department of Geological and Environmental Sciences, Stanford University, Stanford, California 94305 (United States); Zalden, Peter [SLAC National Accelerator Laboratory, Stanford Institute for Materials and Energy Sciences, Menlo Park, California 94025 (United States)] [SLAC National Accelerator Laboratory, Stanford Institute for Materials and Energy Sciences, Menlo Park, California 94025 (United States); Wuttig, Matthias [I. Physikalisches Institut (IA), RWTH Aachen University, 52056 Aachen (Germany) [I. Physikalisches Institut (IA), RWTH Aachen University, 52056 Aachen (Germany); JARA – Fundamentals of Future Information Technology, RWTH Aachen University, 52056 Aachen (Germany); Lindenberg, Aaron M. [SLAC National Accelerator Laboratory, Stanford Institute for Materials and Energy Sciences, Menlo Park, California 94025 (United States) [SLAC National Accelerator Laboratory, Stanford Institute for Materials and Energy Sciences, Menlo Park, California 94025 (United States); Department of Materials Science and Engineering, Stanford University, Stanford, California 94305 (United States); SLAC National Accelerator Laboratory, PULSE Institute, Menlo Park, California 94025 (United States)

    2013-11-04

    We used high-pressure Raman spectroscopy to study the evolution of vibrational frequencies of the phase change materials (PCMs) Ge{sub 2}Sb{sub 2}Te{sub 5}, GeSb{sub 2}Te{sub 4}, and SnSb{sub 2}Te{sub 4}. We found that the critical pressure for triggering amorphization in the PCMs decreases with increasing vacancy concentration, demonstrating that the presence of vacancies, rather than differences in the atomic covalent radii, is crucial for pressure-induced amorphization in PCMs. Compared to the as-deposited amorphous phase, the pressure-induced amorphous phase has a similar vibrational spectrum but requires much lower laser power to transform into the crystalline phase, suggesting different kinetics of crystallization, which may have implications for applications of PCMs in non-volatile data storage.

  5. Some observations in high pressure rheology of lubricants

    NASA Technical Reports Server (NTRS)

    Bair, S.; Winer, W. O.

    1981-01-01

    Experimental data are presented on viscosity, elastic shear modulus, and limiting shear stress of 12 liquid lubricants. It is shown that transition histories do affect the limiting shear stress of the materials in the form of isothermal compression resulting in a lower density and lower limiting stress than isobaric cooling. The measured limiting shear stress agrees with EHD traction data at slide-to-roll ratios of 0.1 or more. In pressure viscosity measurements of the polymer solutions, it is found that for some temperatures, the pressure viscosity coefficient of the blend is slightly less than that of the base, which results in the crossing of the viscosity-pressure isotherms at high pressures.

  6. Hydrostatic Pressure Sensing with High Birefringence Photonic Crystal Fibers

    PubMed Central

    Fávero, Fernando C.; Quintero, Sully M. M.; Martelli, Cicero; Braga, Arthur M.B.; Silva, Vinícius V.; Carvalho, Isabel C. S.; Llerena, Roberth W. A.; Valente, Luiz C. G.

    2010-01-01

    The effect of hydrostatic pressure on the waveguiding properties of high birefringence photonic crystal fibers (HiBi PCF) is evaluated both numerically and experimentally. A fiber design presenting form birefringence induced by two enlarged holes in the innermost ring defining the fiber core is investigated. Numerical results show that modal sensitivity to the applied pressure depends on the diameters of the holes, and can be tailored by independently varying the sizes of the large or small holes. Numerical and experimental results are compared showing excellent agreement. A hydrostatic pressure sensor is proposed and demonstrated using an in-fiber modal interferometer where the two orthogonally polarized modes of a HiBi PCF generate fringes over the optical spectrum of a broad band source. From the analysis of experimental results, it is concluded that, in principle, an operating limit of 92 MPa in pressure could be achieved with 0.0003% of full scale resolution. PMID:22163435

  7. Use of high hydrostatic pressure to produce high quality and safe fresh pork sausage

    E-print Network

    Huang, Mei

    1997-01-01

    transmitting medium) on the following page, The isostatic pressing systems may be operated as warm isostatic pressing (WIP) systems (Mertens, I993). WIP is a forming technique. Isostatic pressure is applied in combination with temperature between ambient... by indirect compression of the pressure transmitting medium 18 2. 2. 2 High Pressure Equipment A "warm isostatic pressing system" (model EPSI 4-10-100), is available from Engineered Pressure System Inc. , (EPSI), a subsidiary of National Forge Co...

  8. Technical and economic evaluation of ten high temperature, high pressure particulate cleanup systems for pressurized fluidized bed combustion

    Microsoft Academic Search

    L. N. Rubow; M. Borden; T. L. Buchanan; J. A. C. Cramp; W. H. Fischer; M. G. Klett; S. M. Maruvada; E. T. Nelson; R. E. Weinstein; R. Zaharchuk

    1984-01-01

    The objective of this analysis was to provide a technical and economic evaluation of the ten high temperature, high pressure (HTHP) systems for the purpose of prioritizing them according to performance, cost, and general viability of achieving commercial status. The scope primarily included reviewing\\/normalizing test experience to date, normalizing commercial designs, developing normalized capital and operating costs for each system,

  9. Desirability of oysters treated by high pressure processing at different temperatures and elevated pressures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organoleptic changes in sterile triploid oysters (Crassostrea virginica) induced by high pressure processing (HPP) were investigated using a volunteer panel. Using a 1-7 hedonic scale, where seven is “like very much”, and one is “dislike very much”, oysters were evaluated organoleptically for flavo...

  10. Investigations on the influence of pressure, current and electrode gap in high-pressure mercury lamps

    Microsoft Academic Search

    P. Flesch; M. Neiger

    2005-01-01

    This paper is concerned with the numerical simulation of high-intensity discharge lamps, focusing on the influence of pressure, current and electrode gap on plasma, anode and cathode properties. The interaction between electrodes and plasma is taken into account. Comparisons between experimental findings and numerical results show that the observed increase in the total lamp voltage caused by an increasing lamp

  11. A temperature compensated pressure transducer for high temperature, high pressure applications 

    E-print Network

    Lippka, Sandra Margaret

    1991-01-01

    that it would cost over f400 for 13 Laser Source Beam Spiitter Mod. Fiber Sensor pressure Reference Fiber Photo Detector Signal Processor Fig. 4. MMaC-Zeehnde inierferometric pressure sensor the the fibers alone. Of further consideration... the equations necessary to determine both thicknesses. Although Inconnel has an ultimate tensile strength of 172 ksi at 1000'F. its 0. &'3& creep strength ol' 120 ksi iras used to deteriuine the diaphragm thickness instea&i. This number is based upon 10. 000...

  12. High-pressure light scattering apparatus to study pressure-induced phase separation in polymer solutions

    NASA Astrophysics Data System (ADS)

    Xiong, Yan; Kiran, Erdogan

    1998-03-01

    A new high-pressure time- and angle-resolved light scattering apparatus has been developed to study the kinetics of phase separation in polymer solutions and other fluid mixtures under pressure at near- and supercritical conditions. The system consists of a high-pressure polymer loading chamber, a solvent charge line, a variable-volume scattering cell (with a built-in movable piston connected to a pressure generator, and an expansion rod driven by an air-actuated diaphragm), and a recirculation pump which are all housed in a temperature-controlled oven. The system is operable at pressures up to 70 MPa, and temperatures up to 473 K. The scattering cell is a short path-length cell made of two flat sapphire windows that are separated by 250 ?m. It is designed to permit measurements of transmitted and scattered light intensities over an angle range from 0° to 30°. A linear image sensor with 256 elements is used to monitor the time evolution of the scattered light intensities at different angles. With this sensor, the angle range from 2° to 13° is scanned at a sampling rate of 3.2 ms/scan. The pressure quenches are achieved by movement of the air-actuated movable expansion rod, or by the movement of the piston with the aid of the pressure generator to bring about either rapid (at rates approaching 2000 MPa/s) or slow pressure changes in the system. Quench depth is also adjustable, and very deep (70 MPa) or very shallow (as low as 0.1 MPa) pressure quenches are readily achievable. The temperature and the pressure of the solution in the scattering cell, and the transmitted and scattered light intensities at different angles are recorded in real time through a computerized data acquisition system before and during phase separation. The experimental system is especially suited to follow the kinetics of phase separation in polymer solutions and to assess the metastable and unstable regions where phase separation proceeds by the nucleation and growth, and the spinodal decomposition mechanisms, respectively. The capability of the instrument is demonstrated for polystyrene/methylcyclohexane solutions.

  13. High-pressure water injection injury: emergency presentation and management.

    PubMed

    Subramaniam, Rathan M; Clearwater, Gary M

    2002-09-01

    Presentations of high-pressure water blaster injuries to the emergency department are varied. Though these injuries are sometimes described as a 'benign variant' of high-pressure injection injuries, external appearances can be deceptive. These injuries can produce an unexpected pattern of severe internal injury and infectious complications. Such injuries are surgical emergencies and must be evaluated quickly and thoroughly in the emergency department. We review the current literature of these injuries and present the first reported case involving a forearm injury. PMID:12487051

  14. Patterned anvils for high pressure measurements at low temperature.

    PubMed

    Welzel, Oliver P; Grosche, F Malte

    2011-03-01

    Multiprobe high pressure measurements require electrical leads in the sample chamber. Compared to conventional wire-based techniques, metallic tracks patterned onto the anvil surface improve reliability and ease of use, and enable novel and more demanding measurements under high pressure. We have developed new anvil designs based on sputter-deposited tracks on alumina and moissanite anvils. These anvils allow convenient and reliable measurements of electrical transport properties or of the magnetic susceptibility under hydrostatic conditions, as demonstrated by test measurements on Pb and Ca(3)Ru(2)O(7). PMID:21456757

  15. Patterned anvils for high pressure measurements at low temperature

    SciTech Connect

    Welzel, Oliver P.; Grosche, F. Malte [Cavendish Laboratory, Department of Physics, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom)

    2011-03-15

    Multiprobe high pressure measurements require electrical leads in the sample chamber. Compared to conventional wire-based techniques, metallic tracks patterned onto the anvil surface improve reliability and ease of use, and enable novel and more demanding measurements under high pressure. We have developed new anvil designs based on sputter-deposited tracks on alumina and moissanite anvils. These anvils allow convenient and reliable measurements of electrical transport properties or of the magnetic susceptibility under hydrostatic conditions, as demonstrated by test measurements on Pb and Ca{sub 3}Ru{sub 2}O{sub 7}.

  16. Patterned anvils for high pressure measurements at low temperature

    NASA Astrophysics Data System (ADS)

    Welzel, Oliver P.; Grosche, F. Malte

    2011-03-01

    Multiprobe high pressure measurements require electrical leads in the sample chamber. Compared to conventional wire-based techniques, metallic tracks patterned onto the anvil surface improve reliability and ease of use, and enable novel and more demanding measurements under high pressure. We have developed new anvil designs based on sputter-deposited tracks on alumina and moissanite anvils. These anvils allow convenient and reliable measurements of electrical transport properties or of the magnetic susceptibility under hydrostatic conditions, as demonstrated by test measurements on Pb and Ca3Ru2O7.

  17. Large volume high-pressure cell with supported moissanite anvils

    SciTech Connect

    Xu, J.; Mao, H.-k.; Hemley, R.J.; Hines , E. (CIW/GL)

    2010-11-16

    The recently developed moissanite anvil cell (MAC) has become a useful device for achieving both high-pressure and large sample volume in an anvil cell. We describe two improvements in the basic design of the MAC. First, the loading environment has been optimized by centering the load. Second, a variety of supported systems have been examined to provide anvil stability at high loads with large anvils. Sample volumes that are nearly three orders magnitude greater than allowed by conventional diamond anvil cells can be pressurized and characterized at {approx}50 GPa.

  18. Large volume high-pressure cell with supported moissanite anvils

    NASA Astrophysics Data System (ADS)

    Xu, Ji-an; Mao, Ho-kwang; Hemley, Russell J.; Hines, Earl

    2004-04-01

    The recently developed moissanite anvil cell (MAC) has become a useful device for achieving both high-pressure and large sample volume in an anvil cell. We describe two improvements in the basic design of the MAC. First, the loading environment has been optimized by centering the load. Second, a variety of supported systems have been examined to provide anvil stability at high loads with large anvils. Sample volumes that are nearly three orders magnitude greater than allowed by conventional diamond anvil cells can be pressurized and characterized at ˜50 GPa.

  19. Kinetics of Formic Acid at High Pressure and Temperature

    NASA Astrophysics Data System (ADS)

    Howard, W. Michael; Fried, Laurence E.; Melius, Carl F.; Montgomery, Wren B.; Zaug, Joesph M.; Goncharov, Alexander F.

    2004-03-01

    We have developed a detailed kinetic model to follow the decomposition of formic acid at modestly high pressures (1-10 GPa) and temperature (500-1000K) and further include our refinement of a fluid exponential-6 equation of state for formic acid and corresponding reaction species. We also include the effects of bimolecular and water catalyzed reactions, calculated from ab initio molecular orbital calculations. We present a comparison between our simulations and experimental observations made using near-simultaneous high-pressure FTIR and Raman spectroscopy. We discuss, in detail, the implications our experimental observations provide in relation to computed reaction timescales and dominant species employed in our model.

  20. Anomalous Raman features of silicon nanowires under high pressure

    NASA Astrophysics Data System (ADS)

    Bhattacharyya, Somnath; Churochkin, Dmitry; Erasmus, Rudolph M.

    2010-10-01

    The potential of silicon nanowires (SiNWs), (diameter <10 nm) to transform into rigid bundlelike structures with distinct phonon confinement under high pressure (?15 GPa), instead of amorphizing as per previous reports, is demonstrated using in situ Raman spectroscopy. The observed splitting of the second order transverse optical (2TO) Raman mode into 2TO(L) and 2TO(W) phonon modes at ?5 GPa establishes a highly anisotropic and mode-dependent pressure response of these SiNWs. Properties of these structures are superior compared to other nanostructured silicon and bulk-Si in terms of increased linear modulus, more localized phonon confinement, and less anharmonicity.

  1. Capillary toroid cavity detector for high pressure NMR

    DOEpatents

    Gerald, II, Rex E. (Brookfield, IL); Chen, Michael J. (Downers Grove, IL); Klingler, Robert J. (Glenview, IL); Rathke, Jerome W. (Honer Glen, IL); ter Horst, Marc (Chapel Hill, NC)

    2007-09-11

    A Toroid Cavity Detector (TCD) is provided for implementing nuclear magnetic resonance (NMR) studies of chemical reactions under conditions of high pressures and temperatures. A toroid cavity contains an elongated central conductor extending within the toroid cavity. The toroid cavity and central conductor generate an RF magnetic field for NMR analysis. A flow-through capillary sample container is located within the toroid cavity adjacent to the central conductor to subject a sample material flowing through the capillary to a static magnetic field and to enable NMR spectra to be recorded of the material in the capillary under a temperature and high pressure environment.

  2. High Pressure Angle Gears: Comparison to Typical Gear Designs

    NASA Technical Reports Server (NTRS)

    Handschuh, Robert F.; Zabrajsek, Andrew J.

    2010-01-01

    A preliminary study has been completed to determine the feasibility of using high-pressure angle gears in aeronautic and space applications. Tests were conducted in the NASA Glenn Research Center (GRC) Spur Gear Test Facility at speeds up to 10,000 rpm and 73 N*m (648 in.*lb) for 3.18, 2.12, and 1.59 module gears (8, 12, and 16 diametral pitch gears), all designed to operate in the same test facility. The 3.18 module (8-diametral pitch), 28 tooth, 20deg pressure angle gears are the GRC baseline test specimen. Also, 2.12 module (12-diametral pitch), 42 tooth, 25deg pressure angle gears were tested. Finally 1.59 module (16-diametral pitch), 56 tooth, 35deg pressure angle gears were tested. The high-pressure angle gears were the most efficient when operated in the high-speed aerospace mode (10,000 rpm, lubricated with a synthetic turbine engine oil), and produced the lowest wear rates when tested with a perfluoroether-based grease. The grease tests were conducted at 150 rpm and 71 N*m (630 in.*lb).

  3. Ignition during hydrogen release from high pressure into the atmosphere

    NASA Astrophysics Data System (ADS)

    Oleszczak, P.; Wolanski, P.

    2010-12-01

    The first investigations concerned with a problem of hydrogen jet ignition, during outflow from a high-pressure vessel were carried out nearly 40 years ago by Wolanski and Wojcicki. The research resulted from a dramatic accident in the Chorzow Chemical Plant Azoty, where the explosion of a synthesis gas made up of a mixture composed of three moles of hydrogen per mole of nitrogen, at 300°C and 30 MPa killed four people. Initial investigation had excluded potential external ignition sources and the main aim of the research was to determine the cause of ignition. Hydrogen is currently considered as a potential fuel for various vehicles such as cars, trucks, buses, etc. Crucial safety issues are of potential concern, associated with the storage of hydrogen at a very high pressure. Indeed, the evidence obtained nearly 40 years ago shows that sudden rupture of a high-pressure hydrogen storage tank or other component can result in ignition and potentially explosion. The aim of the present research is identification of the conditions under which hydrogen ignition occurs as a result of compression and heating of the air by the shock wave generated by discharge of high-pressure hydrogen. Experiments have been conducted using a facility constructed in the Combustion Laboratory of the Institute of Heat Engineering, Warsaw University of Technology. Tests under various configurations have been performed to determine critical conditions for occurrence of high-pressure hydrogen ignition. The results show that a critical pressure exists, leading to ignition, which depends mainly on the geometric configuration of the outflow system, such as tube diameter, and on the presence of obstacles.

  4. Modelling the high pressure mercury discharge lamp warm-up

    SciTech Connect

    Zissis, G.; Charrada, K. [Univ. P. Sabatier, Toulouse (France). Lab. Gas Discharges; Stambouli, M. [E.N.S.S.T.T., Tunis (Tunisia)

    1994-12-31

    Light sources based on the high pressure mercury discharge need an important start-up time. During this time the mercury pressure changes strongly, e.g. 7 orders of magnitude between the ignition moment and the nominal discharge operation. Discharge properties change fundamentally. Therefore at the beginning the authors deal with a low-pressure mercury-rare gas discharge and at the end with a high pressure discharge practically in pure mercury. The rapid evaluation of the typical discharge features during the warm-up may have serious consequences on the wearing out of the components of the network distribution as well as on certain applications. Thus, the simulation of the high pressure mercury lamp during the start-up phase is a very important problem. Unfortunately a self-consistent model describing the whole phenomena during the start-up time would be very complicated because of the numerous and various physical processes that should be taken into account. In fact, to simplify the start-up description, it is possible, in a first approximation, to divide the start-up into three phases: (1) post-ignition; (2) evaporation; (3) pre-operating regime. First and last phases of start-up time can be successfully simulated by using two models describing essentially the main phenomena taking place during these periods. Thus, a classical self-consistent collisional-radiative model for the low-pressure luminescent lamps can be used for the description of the first phase. The last phase can be simulated by a model based on the LTE concept. However, neither classical low-pressure nor LTE model can be used for the middle phase of start-up. For this reason a specific model has been developed.

  5. Ultra-high pressure water jet: Baseline report; Summary

    SciTech Connect

    NONE

    1997-07-31

    The Husky{trademark} is an ultra high pressure waterjet cutting tool system. The pump is mounted on a steel tube frame which includes slots for transport by a forklift. The Husky{trademark} features an automatic shutdown for several conditions such as low oil pressure and high oil temperature. Placement of the Husky{trademark} must allow for a three foot clearance on all sides for operation and service access. At maximum continuous operation, the output volume is 7.2 gallons per minute with an output pressure of 40,000 psi. A diesel engine provides power for the system. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

  6. Energy efficient engine: High pressure turbine uncooled rig technology report

    NASA Technical Reports Server (NTRS)

    Gardner, W. B.

    1979-01-01

    Results obtained from testing five performance builds (three vane cascades and two rotating rigs of the Energy Efficient Engine uncooled rig have established the uncooled aerodynamic efficiency of the high-pressure turbine at 91.1 percent. This efficiency level was attained by increasing the rim speed and annulus area (AN(2)), and by increasing the turbine reaction level. The increase in AN(2) resulted in a performance improvement of 1.15 percent. At the design point pressure ratio, the increased reaction level rig demonstrated an efficiency of 91.1 percent. The results of this program have verified the aerodynamic design assumptions established for the Energy Efficient Engine high-pressure turbine component.

  7. carbonate solid solution at high pressures up to 55 GPa

    NASA Astrophysics Data System (ADS)

    Spivak, Anna; Solopova, Natalia; Cerantola, Valerio; Bykova, Elena; Zakharchenko, Egor; Dubrovinsky, Leonid; Litvin, Yuriy

    2014-09-01

    Magnesite, siderite and ferromagnesites Mg1- x Fe x CO3 ( x = 0.05, 0.09, 0.2, 0.4) were characterized using in situ Raman spectroscopy at high pressures up to 55 GPa. For the Mg-Fe-carbonates, the Raman peak positions of six modes (T, L, ?4, ?1, ?3 and 2?2) in the dependence of iron content in the carbonates at ambient conditions are presented. High-pressure Raman spectroscopy shows that siderite undergoes a spin transition at ~40 GPa. The examination of the solid solutions with compositions Mg0.6Fe0.4CO3, Mg0.8Fe0.2CO3, Mg0.91Fe0.09CO3 and Mg0.95Fe0.05CO3 indicates that with increase in the amount of the Fe spin transition pressure increases up to ~45 GPa.

  8. A Graphene-Based Resistive Pressure Sensor with Record-High Sensitivity in a Wide Pressure Range

    PubMed Central

    Tian, He; Shu, Yi; Wang, Xue-Feng; Mohammad, Mohammad Ali; Bie, Zhi; Xie, Qian-Yi; Li, Cheng; Mi, Wen-Tian; Yang, Yi; Ren, Tian-Ling

    2015-01-01

    Pressure sensors are a key component in electronic skin (e-skin) sensing systems. Most reported resistive pressure sensors have a high sensitivity at low pressures (<5?kPa) to enable ultra-sensitive detection. However, the sensitivity drops significantly at high pressures (>5?kPa), which is inadequate for practical applications. For example, actions like a gentle touch and object manipulation have pressures below 10?kPa, and 10–100?kPa, respectively. Maintaining a high sensitivity in a wide pressure range is in great demand. Here, a flexible, wide range and ultra-sensitive resistive pressure sensor with a foam-like structure based on laser-scribed graphene (LSG) is demonstrated. Benefitting from the large spacing between graphene layers and the unique v-shaped microstructure of the LSG, the sensitivity of the pressure sensor is as high as 0.96?kPa?1 in a wide pressure range (0 ~ 50?kPa). Considering both sensitivity and pressure sensing range, the pressure sensor developed in this work is the best among all reported pressure sensors to date. A model of the LSG pressure sensor is also established, which agrees well with the experimental results. This work indicates that laser scribed flexible graphene pressure sensors could be widely used for artificial e-skin, medical-sensing, bio-sensing and many other areas. PMID:25721159

  9. Pressure dependence on the reaction propagation rate of PETN at high pressure

    SciTech Connect

    Foltz, M.F.

    1993-04-01

    The reaction propagation rate (RPR) of the sensitive high explosive pentaerythritol tetranitrate (PETN) was measured in a diamond anvil cell (DAC) over the pressure range of 2--20 GPa. The experimental technique used is the same as that previously reported. The RPR data shows that it burns one to two orders of magnitude faster in the DAC than 1,3,5,-triamino-2,4,6-trinitrobenzene (TATB) and nitromethane (CH{sub 3}NO{sub 2}) respectively. The PETN RPR curve did not show sample pressure-dependent behavior like that of nitromethane, but instead varied abruptly like the RPR curve of TATB. In order to interpret these changes, static-pressure DAC mid-IR FTIR spectra were taken of micro-pellets of PETN embedded in KBr. The relationship between changes in the spectra, the RPR curve, and published single crystal PETN wedge test data are discussed.

  10. High Pressure Resistivity Measurements of the Itinerant Ferromagnet Cobalt Disulphide

    NASA Astrophysics Data System (ADS)

    Barakat, Samira; Braithwaite, Daniel; Alireza, Patricia; Wilson, John; Flouquet, Jacques; Lonzarich, Gilbert

    2004-03-01

    Cobalt disulphide (CoS_2) is an itinerant ferromagnet with a Curie temperature of Tc = 121 K. It has a cubic crystal structure of the pyrite type and displays full inversion symmetry. Previous work showed that Tc in CoS2 decreases with the application of pressure and the ferromagnetic transition changes from 2^nd to weakly 1^st order for p>0.4 GPa. A moissanite anvil high pressure cell was used to suppress the magnetic transition of CoS2 at a critical pressure of p_c?7 GPa. Tc was deduced from the magnetic susceptibility measured with a micro-coil system. Measurements of the electrical resistivity of CoS2 were performed using a Bridgman anvil cell up to pressures of p=14 GPa, i.e. up to twice the critical pressure. The temperature dependence of the resistivity at low temperatures (200mK-10K) changes from a power-law with exponent n=2 in the ferromagnetic phase to n<1.7 as the ferromagnetic transition is suppressed to zero temperature. The exponent recovers to n=2 at the highest pressures.

  11. Structure of combusting monopropellant sprays at high-pressures

    SciTech Connect

    Lee, T.

    1990-01-01

    An experimental and theoretical study of combusting monopropellant (hydroxylammonium-nitrate-based liquid gun propellants) sprays at pressures of 3 to 9 MPa was considered. Measurements of spray combustion properties included liquid volume fraction profiles, drop size distributions, and liquid mass flux profiles. Locally-homogeneous and separated flow analyses were developed to estimate the structure of the combusting monopropellant sprays. In addition, monopropellant drop combustion properties were observed and drop burning rates were measured (for use in the separated flow analysis) using drops supported in a combustion gas environment at pressures of 0.2 to 7.0 MPa. Observations of monopropellant drop combustion properties showed that subsurface liquid reactions leading to bubble growth and microexplosions dominated the process at low pressures while conventional surface gasification dominated the process at high pressures. The drop burning rates of 10 to 20 mm/s, with weak pressure dependence, were observed. Present findings were consistent with measurements for gelled propellants at pressures greater than 10 mPa. Present measurements of monopropellant spray combustion properties yielded a much larger liquid-containing region than earlier measurements. Furthermore, locally-homogeneous flow predictions generally overestimated rates of spray development for present test conditions, since separated-flow effects due to non-negligible relative phase velocities, finite interphase transport rates, and finite rates of drop combustion were important. In contrast, the present separated-flow analysis yielded the correct trends of variations of Sauter mean diameters, drop size distributions, and liquid mass flow rates of the sprays.

  12. Low pressure high speed Stirling air engine. Final technical report

    SciTech Connect

    Ross, M.A.

    1980-06-16

    The purpose of this project was to design, construct and test a simple, appropriate technology low pressure, high speed, wood-fired Stirling air engine of 100 W output. The final design was a concentric piston/displacer engine of 454 in. bore and 1 in. stroke with a rhombic drive mechanism. The project engine was ultimately completed and tested, using a propane burner for all tests as a matter of convenience. The 100 W aim was exceeded, at atmospheric pressure, over a wide range of engine speed with the maximum power being 112 W at 1150 rpm. A pressure can was constructed to permit pressurization; however the grant funds were running out, and the only pressurized power test attempted was unsuccessful due to seal difficulties. This was a disappointment because numerous tests on the 4 cubic inch engine suggested power would be more than doubled with pressurization at 25 psig. A manifold was designed and constructed to permit operation of the engine over a standard No. 40 pot bellied stove. The engine was run successfully, but at reduced speed and power, over this stove. The project engine started out being rather noisy in operation, but modifications ultimately resulted in a very quiet engine. Various other difficulties and their solutions also are discussed. (LCL)

  13. Measurement of thermal diffusivity of rocks at high pressure

    SciTech Connect

    Mirkovich, V.V.; Durham, W.B.; Heard, H.C.

    1982-10-01

    A method for measurement of thermal diffusivity at high hydrostatic pressure was developed by adapting a radial symmetry heat flow method wherein a sinusoidal heat wave is applied to the cylindrical surface of the sample. The accuracy of the measuring system was tested using Pyroceram 9606. Data obtained were within 5% of published values at all temperatures to 400/sup 0/C and no dependence upon pressure was observed. Thermal diffusivity of three crystalline igneous rock specimens was measured at temperatures from 32 to 400/sup 0/C and pressures from 0.1 to 200 MPa. The results for Creighton quartz diorite showed only limited temperature and pressure dependence. In the case of Stripa and Westerly granites, this dependence was found to be more substantial. Thermal diffusivity of Stripa granite decreased by more than 50% from 32 to 400/sup 0/C and that of Westerly granite decreased by approximately 40% over the same range. At 32/sup 0/C and 200 MPa, thermal diffusivity for both rocks was higher by approximately 10% than that measured at 0.1 MPa. At higher temperatures the difference in thermal diffusivity between the two pressure levels increased. An anomaly was observed in Stripa and Westerly granite in the temperature range 32 to 65/sup 0/C: thermal diffusivity increased with increasing temperature. The anomaly is consistent with recently observed thermal expansivity in these rocks as a function of pressure and temperature.

  14. In-situ Single-Crystal Neutron Diffraction on Hydrogen Related High-Pressure Compounds at High-Pressure

    Microsoft Academic Search

    J. Xu; H. Mao; J. Shu; R. J. Hemley; J. Loveday; R. J. Nelmes; Y. Zhao; D. He

    2002-01-01

    The hydrogen bonding at high densities is of great interest to Earth sciences, condensed matter physics, planetary astronomy, and energy application. Using the large size diamond anvil cell (DAC) and recent developed moissanite anvil cell (MAC) [1], we will now be able to conduct high-quality in-situ neutron-diffraction measurements on single crystals at high pressure. This is a unique development of

  15. 26. VIEW OF PUMP ROOM, SHOWING PORTIONS OF HIGH PRESSURE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. VIEW OF PUMP ROOM, SHOWING PORTIONS OF HIGH PRESSURE AIR SYSTEM AT LEFT AND CENTER AND OVERFLOW STORAGE TANK AT RIGHT, LOOKING NORTHWEST - U.S. Naval Submarine Base, New London Submarine Escape Training Tank, Albacore & Darter Roads, Groton, New London County, CT

  16. Commensurate N2-O2 Alloys at High Pressures

    Microsoft Academic Search

    Bruce Baer

    2005-01-01

    Several high pressure binary mixtures have been investigated over the past fifteen years. The phase diagrams of many of these systems have been shown to contain one or more van der Waals compounds. Often, the crystal structures of these compounds are quite unique from those of the parent pure compounds. In this talk we will look at the compounds formed

  17. Simple Molecular Systems at High Pressures and Temperatures

    Microsoft Academic Search

    Alexander Goncharov; Jonathan Crowhurst

    2007-01-01

    Knowledge of the elastic, optical and vibrational properties of materials under extreme conditions of high pressure and temperature is crucial for interpreting the results of seismological and planetary observations, for materials science, and for improving our understanding of fundamental physics and chemistry under such conditions. We will present the results of Raman, infrared, and x-ray diffraction measurements of hydrogen, water,

  18. High-field operation of submicrometer devices at atmospheric pressure

    Microsoft Academic Search

    M. J. Madou; S. R. Morrison

    1991-01-01

    An array of micrometer-sized field emitter tips was used to produce ions in air or other gases at atmospheric pressure using only low voltages. The ions are produced by the dissociation of gaseous acids or bases in the high electric field near the tips. For example, with formic or acetic acid, ions are formed with the tip at about -50

  19. Large volume high-pressure cell with supported moissanite anvils

    Microsoft Academic Search

    Ji-An Xu; Ho-Kwang Mao; Russell J. Hemley; Earl Hines

    2004-01-01

    The recently developed moissanite anvil cell (MAC) has become a useful device for achieving both high-pressure and large sample volume in an anvil cell. We describe two improvements in the basic design of the MAC. First, the loading environment has been optimized by centering the load. Second, a variety of supported systems have been examined to provide anvil stability at

  20. Large volume high-pressure cell with supported moissanite anvils

    Microsoft Academic Search

    J. Xu; H.-k. Mao; R. J. Hemley; E. Hines

    2010-01-01

    The recently developed moissanite anvil cell (MAC) has become a useful device for achieving both high-pressure and large sample volume in an anvil cell. We describe two improvements in the basic design of the MAC. First, the loading environment has been optimized by centering the load. Second, a variety of supported systems have been examined to provide anvil stability at