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


1

High temperature pressure gauge  

DOE Patents [OSTI]

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.

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

1981-01-01T23:59:59.000Z

2

High-pressure crystallography  

Science Journals Connector (OSTI)

The history and development of high-pressure crystallography are briefly described and examples of structural transformations in compressed compounds are given. The review is focused on the diamond-anvil cell, celebrating its 50th anniversary this year, the principles of its operation and the impact it has had on high-pressure X-ray diffraction.

Katrusiak, A.

2007-12-21T23:59:59.000Z

3

High pressure counterflow CHF.  

E-Print Network [OSTI]

This is a report of the experimental results of a program in countercurrent flow critical heat flux. These experiments were performed with Freon 113 at 200 psia in order to model a high pressure water system. An internally ...

Walkush, Joseph Patrick

1975-01-01T23:59:59.000Z

4

High pressure oxygen furnace  

DOE Patents [OSTI]

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. 5 figs.

Morris, D.E.

1992-07-14T23:59:59.000Z

5

High pressure oxygen furnace  

DOE Patents [OSTI]

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.

Morris, Donald E. (Kensington, CA)

1992-01-01T23:59:59.000Z

6

High-Pressure Hydrogen Tanks  

Broader source: Energy.gov [DOE]

Presentation on High-Pressure Hydrogen Tanks for the DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project Review Meeting held February 8-9, 2005 at Argonne National Laboratory

7

Electrokinetically pumped high pressure sprays  

DOE Patents [OSTI]

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.

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

2005-11-01T23:59:59.000Z

8

Fundamentals of high pressure adsorption  

SciTech Connect (OSTI)

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.

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

2009-12-15T23:59:59.000Z

9

High pressure storage vessel  

DOE Patents [OSTI]

Disclosed herein is a composite pressure vessel with a liner having a polar boss and a blind boss a shell is formed around the liner via one or more filament wrappings continuously disposed around at least a substantial portion of the liner assembly combined the liner and filament wrapping have a support profile. To reduce susceptible to rupture a locally disposed filament fiber is added.

Liu, Qiang

2013-08-27T23:59:59.000Z

10

High-Pressure Hydrogen Tanks  

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

February 8 February 8 th , 2005 Mark J. Warner, P.E. Principal Engineer Quantum Technologies, Inc. Irvine, CA Low Cost, High Efficiency, Low Cost, High Efficiency, High Pressure Hydrogen Storage High Pressure Hydrogen Storage This presentation does not contain any proprietary or confidential information. 70 MPa Composite Tanks Vent Line Ports Defueling Port (optional) Fill Port Filter Check Valve Vehicle Interface Bracket with Stone Shield In Tank Regulator with Solenoid Lock-off Pressure Relief Device Manual Valve Compressed Hydrogen Storage System In-Tank Regulator Pressure Sensor (not visible here) Pressure Relief Device (thermal) In Tank Gas Temperature Sensor Carbon Composite Shell (structural) Impact Resistant Outer Shell (damage resistant) Gas Outlet Solenoid Foam Dome (impact protection)

11

Steam Oxidation at High Pressure  

SciTech Connect (OSTI)

A first high pressure test was completed: 293 hr at 267 bar and 670{degrees}C; A parallel 1 bar test was done for comparison; Mass gains were higher for all alloys at 267 bar than at 1 bar; Longer term exposures, over a range of temperatures and pressures, are planned to provide information as to the commercial implications of pressure effects; The planned tests are at a higher combination of temperatures and pressures than in the existing literature. A comparison was made with longer-term literature data: The short term exposures are largely consistent with the longer-term corrosion literature; Ferritic steels--no consistent pressure effect; Austenitic steels--fine grain alloys less able to maintain protective chromia scale as pressure increases; Ni-base alloys--more mass gains above 105 bar than below. Not based on many data points.

Holcomb, Gordon R. [NETL; Carney, Casey [URS

2013-07-19T23:59:59.000Z

12

Pressure Relief Devices for High-Pressure Gaseous Storage Systems...  

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

Pressure Relief Devices for High-Pressure Gaseous Storage Systems: Applicability to Hydrogen Technology A. Kostival, C. Rivkin, W. Buttner, and R. Burgess National Renewable Energy...

13

Electrokinetic high pressure hydraulic system  

DOE Patents [OSTI]

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.

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)

2001-01-01T23:59:59.000Z

14

High pressure ceramic joint  

DOE Patents [OSTI]

Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

Ward, Michael E. (Poway, CA); Harkins, Bruce D. (San Diego, CA)

1993-01-01T23:59:59.000Z

15

High pressure ceramic joint  

DOE Patents [OSTI]

Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures. 4 figures.

Ward, M.E.; Harkins, B.D.

1993-11-30T23:59:59.000Z

16

High pressure synthesis gas conversion. Task 3: High pressure profiles  

SciTech Connect (OSTI)

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. 1jungdahlii. 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.

Not Available

1993-05-01T23:59:59.000Z

17

High Pressure Hydrogen Tank Manufacturing  

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

Workshop Workshop High Pressure Hydrogen Tank Manufacturing Mark Leavitt Quantum Fuel Systems Technologies Worldwide, Inc. August 11, 2011 This presentation does not contain any proprietary, confidential, or otherwise restricted information History of Innovations... Announced breakthrough in all-composite lightweight, high capacity, low-cost fuel storage technologies. * Developed a series of robust, OEM compatible electronic control products. Developed H 2 storage system for SunLine Tran-sit Hythane® bus. Awarded patent for integrated module including in-tank regulator * Developed high efficiency H 2 fuel storage systems for DOE Future Truck programs Developed H 2 storage and metering system for Toyota's FCEV platform. First to certify 10,000 psi systems in Japan

18

Electrical Transport Experiments at High Pressure  

SciTech Connect (OSTI)

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.

Weir, S

2009-02-11T23:59:59.000Z

19

High-Pressure Tube Trailers and Tanks  

Broader source: Energy.gov [DOE]

Presentation on High-Pressure Tube Trailers and Tanks for the DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project Review Meeting held February 8-9, 2005 at Argonne National Laboratory

20

High-pressure microhydraulic actuator  

DOE Patents [OSTI]

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.

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

2008-06-10T23:59:59.000Z

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


21

Sandia National Laboratories: High-Pressure and High-Temperature...  

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

ClimateECClimateCarbon CaptureHigh-Pressure and High-Temperature Neutron Reflectometry Cell for Solid-Fluid Interface Studies High-Pressure and High-Temperature Neutron...

22

Chapter 9 - Vacuum and High-Pressure Distillation  

Science Journals Connector (OSTI)

Abstract In industrial practice, multistage distillation operations are carried out over a wide range of operating pressures, from about 0.1 to 40 bar (10,000 to 40·105 Pa). Major factors in choosing the operating pressure are the temperatures of the available cooling and heating media, with water and low-pressure steam being the most convenient ones. Volatile materials require high pressure to raise their condensation temperature to the desired level. Relative volatility tends to decrease with increasing pressure, and, thermodynamically, the upper limit is the critical temperature of the components in the feed. In such cases, a lower operating pressure is chosen and refrigeration must be employed for condensation of overhead vapor instead of cooling water or air. When dealing with high-boiling material, the upper limit for setting the operating pressure depends on the heat sensitivity of the bottom product components. This often requires distilling under an appropriate vacuum in conjunction with a low enough pressure drop to reduce the column bottom temperature accordingly. From the column design point of view, the operating pressure dictates to a great extent the choice and design of internals, and it influences significantly their functionality and overall performance. The main objective of the present chapter is to address and discuss operating pressure selection criteria as well as pressure effects on stage and reflux requirement, vapor and liquid properties, distillation process in general, and trayed and packed-column hydraulics and efficiency in particular.

Žarko Oluji?

2014-01-01T23:59:59.000Z

23

Neutron scattering at high pressure  

Science Journals Connector (OSTI)

Neutron scattering spectra at pressures up to 30 kilobar in the temperature range 300–4 K have been obtained with a compact clamped type apparatus. The pressure cell geometry by allowing the detection of neutronsscattered in a plane makes it compatible with operation on crystal spectrometers both for elastic and inelastic scattering. The instrument is light (4.5 kg) and easy to move. An external diameter of 68 mm makes the pressure cell adaptable to standard cryostats or furnaces.

D. Bloch; J. Paureau; J. Voiron; G. Parisot

1976-01-01T23:59:59.000Z

24

High Pressure Hydrogen Tank Manufacturing  

Broader source: Energy.gov (indexed) [DOE]

Cycles Fuel Lines * 10,000 psi nominal working pressure * O-ring face seal connections * CNC bent to CAD data * 316 Stainless Steel (Other materials available) * Welded end form or...

25

BIOMACROMOLECULES UNDER HIGH HYDROSTATIC PRESSURE  

E-Print Network [OSTI]

of water into the protein rather than the transfer of hydrophobic residues into water. To investigate water. Gil Toombes for teaching me SAXS analysis and help with the pressure pump motor control, Buz Barstow

Gruner, Sol M.

26

NETL- High-Pressure Combustion Research Facility  

SciTech Connect (OSTI)

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.

None

2013-07-08T23:59:59.000Z

27

NETL- High-Pressure Combustion Research Facility  

ScienceCinema (OSTI)

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.

None

2014-06-26T23:59:59.000Z

28

High-Pressure Model Catalyst System | EMSL  

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

of one atmosphere or below in a reactor situated just below an ultra-high vacuum (UHV) chamber. In particular, heterogeneous catalytic reactions at realistic pressures over...

29

Recent high pressure photoluminescence studies  

SciTech Connect (OSTI)

In this paper we discuss two studies involving the effect of pressure on luminescence properties of organic molecules in polymeric media. (1) The efficiency of energy transfer from Coumarine 138 to Rhodamine B in polyacrylic acid (PAA) is measured by both steady state and time dependent methods. The Forster efficiency'' obtained by these two methods is consistent and shows the same pressure dependence as efficiencies derived from relative peak intensities. The non-monotonic pressure dependence of the efficiency is accounted for in terms of the properties of the molecules and the media. (2) The effect of pressure on the luminescent efficiency of molecules with two or more possible excited state geometries has been measured. The efficiency is described in terms of the non-radiative dissipation of energy from a planar excited state and the rates of crossing to and from the possible twisted states as well as non-radiative decay from these states. The processes involved in these two studies are pertinent to a number of technologically and biologically important processes. [copyright]American Institute of Physics

Drickamer, H.G.; Lang, J.M.; Dreger, Z.A. (Department of Chemical Engineering, University of Illinois, 1209 W. California Street, Urbana, Illinois 61801 (United States))

1994-07-10T23:59:59.000Z

30

Superconducting high-pressure phases of disilane  

Science Journals Connector (OSTI)

...Superconducting high-pressure phases of disilane 10.1073/pnas.1005242107 Xilian...DC 20015 High-pressure structures of disilane (Si2H6) are investigated extensively...linear-response calculations for Pm-3m disilane at 275 GPa show a large electron-phonon...

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

2010-01-01T23:59:59.000Z

31

Viscosity of liquid Fe at high pressure  

Science Journals Connector (OSTI)

Synchrotron x-ray radiography has been used to measure the viscosity of pure liquid Fe at high pressure and temperature in a large volume press. A probe sphere rising through liquid Fe at high pressure and temperature is imaged, in situ, allowing for the derivation of sample viscosity through a modified form of Stokes’ equation. The effect of pressure on viscosity is fit by the semi empirical framework for transport coefficients in liquid metals, providing experimental verification of constant viscosity at the pressure-dependent melting temperature of liquid Fe where no change in liquid structure occurs.

Michael D. Rutter; Richard A. Secco; Hongjian Liu; Takeyuki Uchida; Mark L. Rivers; Stephen R. Sutton; Yanbin Wang

2002-08-14T23:59:59.000Z

32

Portable high precision pressure transducer system  

DOE Patents [OSTI]

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.

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

1994-04-26T23:59:59.000Z

33

High Pressure Research Questionnaire National High Magnetic Field...  

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

Pressure Research Questionnaire National High Magnetic Field Laboratory Operated by Florida State University, University of Florida, Los Alamos National Laboratory Florida State...

34

High pressure ceramic heat exchanger  

DOE Patents [OSTI]

Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the reinforcing member and having a strengthening member wrapped around the refractory material. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

Harkins, Bruce D. (San Diego, CA); Ward, Michael E. (Poway, CA)

1999-01-01T23:59:59.000Z

35

High pressure ceramic heat exchanger  

DOE Patents [OSTI]

Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

Harkins, Bruce D. (San Diego, CA); Ward, Michael E. (Poway, CA)

1998-01-01T23:59:59.000Z

36

High pressure ceramic heat exchanger  

DOE Patents [OSTI]

Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures. 5 figs.

Harkins, B.D.; Ward, M.E.

1998-09-22T23:59:59.000Z

37

High Temperature Corrosion Test Facilities and High Pressure Test  

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

High Temperature High Temperature Corrosion Test Facilities and High Pressure Test Facilities for Metal Dusting Test Facilities for Metal Dusting Overview Other Facilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr High Temperature Corrosion Test Facilities and High Pressure Test Facilities for Metal Dusting Six corrosion test facilities and two thermogravimetric systems for conducting corrosion tests in complex mixed gas environments, in steam and in the presence of deposits, and five facilities for metal dusting degradation Bookmark and Share The High Temperature Corrosion Test Facilities and High Pressure Test Facilities for Metal Dusting include: High Pressure Test Facility for Metal Dusting Resistance:

38

Bonfire Tests of High Pressure Hydrogen Storage Tanks | Department...  

Broader source: Energy.gov (indexed) [DOE]

Bonfire Tests of High Pressure Hydrogen Storage Tanks Bonfire Tests of High Pressure Hydrogen Storage Tanks These slides were presented at the International Hydrogen Fuel and...

39

Bonfire Tests of High Pressure Hydrogen Storage Tanks  

Broader source: Energy.gov (indexed) [DOE]

Bonfire Tests of High Pressure Hydrogen Storage Tanks International Hydrogen Fuel and Pressure Vessel Forum 2010Beijing, P.R. China September 27, 2010 Bonfire Tests of High...

40

HIGH PRESSURE COAL COMBUSTON KINETICS PROJECT  

SciTech Connect (OSTI)

As part of the U.S. Department of Energy (DoE) initiative to improve the efficiency of coal-fired power plants and reduce the pollution generated by these facilities, DOE has funded the High-Pressure Coal Combustion Kinetics (HPCCK) Projects. A series of laboratory experiments were conducted on selected pulverized coals at elevated pressures with the specific goals to provide new data for pressurized coal combustion that will help extend to high pressure and validate models for burnout, pollutant formation, and generate samples of solid combustion products for analyses to fill crucial gaps in knowledge of char morphology and fly ash formation. Two series of high-pressure coal combustion experiments were performed using SRI's pressurized radiant coal flow reactor. The first series of tests characterized the near burner flame zone (NBFZ). Three coals were tested, two high volatile bituminous (Pittsburgh No.8 and Illinois No.6), and one sub-bituminous (Powder River Basin), at pressures of 1, 2, and 3 MPa (10, 20, and 30 atm). The second series of experiments, which covered high-pressure burnout (HPBO) conditions, utilized a range of substantially longer combustion residence times to produce char burnout levels from 50% to 100%. The same three coals were tested at 1, 2, and 3 MPa, as well as at 0.2 MPa. Tests were also conducted on Pittsburgh No.8 coal in CO2 entrainment gas at 0.2, 1, and 2 MPa to begin establishing a database of experiments relevant to carbon sequestration techniques. The HPBO test series included use of an impactor-type particle sampler to measure the particle size distribution of fly ash produced under complete burnout conditions. The collected data have been interpreted with the help of CFD and detailed kinetics simulation to extend and validate devolatilization, char combustion and pollutant model at elevated pressure. A global NOX production sub-model has been proposed. The submodel reproduces the performance of the detailed chemical reaction mechanism for the NBFZ tests.

Stefano Orsino

2005-03-30T23:59:59.000Z

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


41

Advanced Diagnostics for High Pressure Spray Combustion.  

SciTech Connect (OSTI)

The development of accurate predictive engine simulations requires experimental data to both inform and validate the models, but very limited information is presently available about the chemical structure of high pressure spray flames under engine- relevant conditions. Probing such flames for chemical information using non- intrusive optical methods or intrusive sampling techniques, however, is challenging because of the physical and optical harshness of the environment. This work details two new diagnostics that have been developed and deployed to obtain quantitative species concentrations and soot volume fractions from a high-pressure combusting spray. A high-speed, high-pressure sampling system was developed to extract gaseous species (including soot precursor species) from within the flame for offline analysis by time-of-flight mass spectrometry. A high-speed multi-wavelength optical extinction diagnostic was also developed to quantify transient and quasi-steady soot processes. High-pressure sampling and offline characterization of gas-phase species formed following the pre-burn event was accomplished as well as characterization of gas-phase species present in the lift-off region of a high-pressure n-dodecane spray flame. For the initial samples discussed in this work several species were identified, including polycyclic aromatic hydrocarbons (PAH); however, quantitative mole fractions were not determined. Nevertheless, the diagnostic developed here does have this capability. Quantitative, time-resolved measurements of soot extinction were also accomplished and the novel use of multiple incident wavelengths proved valuable toward characterizing changes in soot optical properties within different regions of the spray flame.

Skeen, Scott A.; Manin, Julien Luc; Pickett, Lyle M.

2014-06-01T23:59:59.000Z

42

Column Design in High Pressure Liquid Chromatography  

Science Journals Connector (OSTI)

......consideration, and the high inlet pressure is the price to be paid for the short analysis time...silicious support impregnated with paraffin oil in reversed phase chromatography. As op...in the above described manner following heating of the product at 450 C. With relatively......

Csaba Horvath; S. R. Lipsky

1969-02-01T23:59:59.000Z

43

Column Design in High Pressure Liquid Chromatography  

Science Journals Connector (OSTI)

......School of Medicine, New Haven, Connecticut Presented at the Fit th International...high inlet pressure is the price to be paid for the short analysis...support impregnated with paraffin oil in reversed phase chromatography...described manner following heating of the product at 450 C. With......

Csaba Horvath; S. R. Lipsky

1969-02-01T23:59:59.000Z

44

High Temperature, High Pressure Devices for Zonal Isolation in Geothermal  

Open Energy Info (EERE)

Temperature, High Pressure Devices for Zonal Isolation in Geothermal Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells Project Type / Topic 1 Recovery Act: Enhanced Geothermal Systems Component Research and Development/Analysis Project Type / Topic 2 Zonal Isolation Project Description For Enhanced Geothermal Systems (EGS), high-temperature high-pressure zonal isolation tools capable of withstanding the downhole environment are needed. In these wells the packers must withstand differential pressures of 5,000 psi at more than 300°C, as well as pressures up to 20,000 psi at 200°C to 250°C. Furthermore, when deployed these packers and zonal isolation tools must form a reliable seal that eliminates fluid loss and mitigates short circuiting of flow from injectors to producers. At this time, general purpose open-hole packers do not exist for use in geothermal environments, with the primary technical limitation being the poor stability of existing elastomeric seals at high temperatures.

45

Flash High-Pressure Condensate to Regenerate Low-Pressure Steam  

Broader source: Energy.gov [DOE]

This tip sheet outlines optimal conditions for flashing high-pressure condensate to regenerate low-pressure steam in steam systems.

46

High-pressure liquid chromatographic gradient mixer  

DOE Patents [OSTI]

A gradient mixer effects the continuous mixing of any two miscible solvents without excessive decay or dispersion of the resultant isocratic effluent or of a linear or exponential gradient. The two solvents are fed under low or high pressure by means of two high performance liquid chromatographic pumps. The mixer comprises a series of ultra-low dead volume stainless steel tubes and low dead volume chambers. The two solvent streams impinge head-on at high fluxes. This initial nonhomogeneous mixture is then passed through a chamber packed with spirally-wound wires which cause turbulent mixing thereby homogenizing the mixture with minimum band-broadening.

Daughton, C.G.; Sakaji, R.H.

1982-09-08T23:59:59.000Z

47

Intense and Highly Energetic Atmospheric Pressure Plasma Jet Arrays.  

E-Print Network [OSTI]

??This thesis documents the efforts taken to produce highly ionized and concentrated atmospheric pressure plasma using an arrayed atmospheric pressure plasma jet (APPJ) system. The… (more)

Furmanski, John

2012-01-01T23:59:59.000Z

48

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

Science Journals Connector (OSTI)

An equation of state for Mg(OH)2 brucite under high-pressure and high-temperature conditions ... -ray diffraction. Pressure dependence of entropy of brucite has been calculated with thermal expansion coefficient....

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

2003-10-01T23:59:59.000Z

49

HIGH PRESSURE COAL COMBUSTION KINETICS PROJECT  

SciTech Connect (OSTI)

SRI has completed the NBFZ test program, made modification to the experimental furnace for the HPBO test. The NBFZ datasets provide the information NEA needs to simulate the combustion and fuel-N conversion with detailed chemical reaction mechanisms. BU has determined a linear swell of 1.55 corresponding to a volumetric increase of a factor of 3.7 and a decrease in char density by the same factor. These results are highly significant, and indicate significantly faster burnout at elevated pressure due to the low char density and large diameter.

Chris Guenther, Ph.D.

2003-01-28T23:59:59.000Z

50

High-pressure coal fuel processor development  

SciTech Connect (OSTI)

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.

Greenhalgh, M.L.

1992-11-01T23:59:59.000Z

51

A University Consortium on Efficient and Clean High-Pressure...  

Broader source: Energy.gov (indexed) [DOE]

Efficient and Clean High-Pressure, Lean Burn (HPLB) Engines A University Consortium on Efficient and Clean High-Pressure, Lean Burn (HPLB) Engines 2010 DOE Vehicle Technologies and...

52

DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project...  

Broader source: Energy.gov (indexed) [DOE]

Delivery High-Pressure Tanks and Analysis Project Review Meeting DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project Review Meeting On February 8-9, 2005, the Department...

53

High-pressure coal fuel processor development  

SciTech Connect (OSTI)

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.

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

1992-12-01T23:59:59.000Z

54

High pressure fiber optic sensor system  

DOE Patents [OSTI]

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.

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

2013-11-26T23:59:59.000Z

55

High-Pressure Tube Trailers and Tanks  

Broader source: Energy.gov (indexed) [DOE]

bending stress: continuous fiber vessels and vessels made of replicants Conformable tanks require internal stiffeners (ribs) to efficiently support the pressure and minimize...

56

Fundamentals of High Pressure Combustion Chapter in High Pressure Processes in Chemical Engineering, Edited by Maximillian Lackner,  

E-Print Network [OSTI]

Fundamentals of High Pressure Combustion Chapter in High Pressure Processes in Chemical Engineering for more than 50 years and are expected to continue to do so [2]. Diesel engines obtain pressures as large as 60atm after ignition [3, 4, 5, 6, 7]. Figure 1 presents a schematic of diesel and gas turbine engine

Miller, Richard S.

57

High-Pressure Hydrogen Tank Testing | Department of Energy  

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

Tank Testing High-Pressure Hydrogen Tank Testing Many types of compressed hydrogen tanks have been certified worldwide and demonstrated in several prototype fuel cell...

58

High pressure and multiferroics materials: a happy marriage  

Science Journals Connector (OSTI)

The effect of high pressure on the synthesis, properties and atomic structure of multiferroic materials with perovskite or perovskite-related structures is reviewed.

Gilioli, E.

2014-10-31T23:59:59.000Z

59

Working with SRNL - Our Facilities- High Pressure Laboratory  

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

The High Pressure Laboratory provides a comprehensive test facility providing the annual testing certification of various nuclear material shipping packages and leak testing...

60

High-pressure Infrared Spectra of Tal and Lawsonite  

SciTech Connect (OSTI)

We present high-pressure infrared spectra of two geologically important hydrous minerals: talc, Mg3Si4O10(OH)2 and lawsonite, CaAl2Si2O7(OH)2{center_dot}H2O,{center_dot}at room temperature. For lawsonite, our data span the far infrared region from 150 to 550 cm-1 and extend to 25 GPa. We combine our new spectroscopic data with previously published high-pressure mid-infrared and Raman data to constrain the Gr{umlt u}neisen parameter and vibrational density of states under pressure. In the case of talc, we present high-pressure infrared data that span both the mid and far infrared from 150 to 3800 cm-1 covering lattice, silicate, and hydroxyl stretching vibrations to a maximum pressure of 30 GPa. Both phases show remarkable metastability well beyond their nominal maximum thermodynamic stability at simultaneous high-pressure and high-temperature conditions.

Scott,H.; Liu, Z.; Hemley, R.; Williams, Q.

2007-01-01T23:59:59.000Z

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


61

High-Pressure Tube Trailers and Tanks  

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

Berry Berry Salvador M. Aceves Lawrence Livermore National Laboratory (925) 422-0864 saceves@LLNL.GOV DOE Delivery Tech Team Presentation Chicago, Illinois February 8, 2005 Inexpensive delivery of compressed hydrogen with ambient temperature or cryogenic compatible vessels * Pressure vessel research at LLNL Conformable (continuous fiber and replicants) Cryo-compressed * Overview of delivery options * The thermodynamics of compressed and cryo-compressed hydrogen storage * Proposed analysis activities * Conclusions Outline We are investigating two techniques for reduced bending stress: continuous fiber vessels and vessels made of replicants Conformable tanks require internal stiffeners (ribs) to efficiently support the pressure and minimize bending stresses Spherical and cylindrical tanks

62

Electrical resistance of Manganin under high static pressures  

Science Journals Connector (OSTI)

The electrical resistance of manganin was measured under pressures up to 220 kbar at room temperature. The pressure was produced by means of a multianvil apparatus using semisintered magnesia for the pressure medium and was calibrated against well?known fixed points. Obtained results show a linear relationship between the resistance and pressure up to 180 kbar with good reproducibility. The pressure coefficient of resistance turns out to be (2.322±0.008) ×10?3 kbar?1 which is in close agreement with the value obtained under hydrostatic conditions. Manganin can be satisfactorily used as a pressure gauge for a high?pressure experiment using a solidpressure medium. The deviation from the linearity observed above 180 kbar is ascribed to either an intrinsic property of Manganin or the uncertainty of the fixed point adopted. If the linearity is assumed above 180 kbar the transition pressure of GaP is estimated to be 206±2 kbar.

N. Fujioka; O. Mishima; S. Endo; N. Kawai

1978-01-01T23:59:59.000Z

63

Geological Aspects of High-Pressure Research  

Science Journals Connector (OSTI)

...garnet-pyroxene assemblage typical of eclogites by heating it for an hour at 1200 C at a pressure...eclogite at the M discontinuity. The geothermal gradient would have to have curved so...kyanite-sillimanite transition three times. The geothermal gradient probably has a slope not far...

F. R. Boyd

1964-07-03T23:59:59.000Z

64

High pressure--high temperature research using high energy synchrotron radiation at the TRISTAN accumulation ring  

SciTech Connect (OSTI)

High energy synchrotron radiation emitted from the bending magnet of the TRISTAN accumulation ring (6.5 GeV) at the National Laboratory for High Energy Physics has been used for the high pressure--high temperature diffraction experiments using a multianvil press system, MAX80. Owing to the specific features of high energy synchroton radiation, significant improvements have been brought to the high pressure research. The wide energy range of diffraction spectrum leads to an increase in the number of observable diffraction peaks in an energy-dispersive method, resulting in an increase in the accuracy of the measurements of the lattice and thermal parameters. Due to the high penetrating power of radiation, diffraction patterns can be taken in a short time from materials containing heavy elements or materials surrounded by a metal foil. Typical examples of high pressure--high temperature experiments with high energy synchrotron radiation are also described.

Kikegawa, T.; Shimomura, O.; Iwasaki, H.; Sato, S.; Mikuni, A.; Iida, A.; Kamiya, N.

1989-07-01T23:59:59.000Z

65

Rotational viscometer for high-pressure, high-temperature fluids  

DOE Patents [OSTI]

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.

Carr, K.R.

1983-06-06T23:59:59.000Z

66

High pressure testing of see-through labyrinth seals  

E-Print Network [OSTI]

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...

Picardo, Arthur Michael

2012-06-07T23:59:59.000Z

67

Neutron scattering at high pressure D. B. McWhan  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

68

Bonding and Electronic Properties of Ice at High Pressure  

E-Print Network [OSTI]

between the nearest oxygen atoms. All ice structures that we discussed so far are insulators. Militzer 1 Bonding and Electronic Properties of Ice at High Pressure B. Militzer Department of Earth of water ice at megabar pressure are characterized with ab initio computer simulations. The focus lies

Militzer, Burkhard

69

Chemistry of nitromethane at very high pressure  

SciTech Connect (OSTI)

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.

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

1989-01-01T23:59:59.000Z

70

High pressure water jet cutting of sugar cane  

E-Print Network [OSTI]

performance was uniform before cutting. A liquid filled bourdon tube gauge was used to deter- mine the prescribed operating pressures. The gauge measured the oil pressure of the intensifier which had a 20 to 1 ratio (Figure 4 ) ~ The gauge pressure...HIGH PRESSURE WATER JET CUTTING OF SUGAR CANE A Thesis by THOMAS DONALD VALCO Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1977 Major Subject...

Valco, Thomas Donald

2012-06-07T23:59:59.000Z

71

Energy Systems High Pressure Test Laboratory (Fact Sheet)  

SciTech Connect (OSTI)

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.

Not Available

2011-10-01T23:59:59.000Z

72

HIGH PRESSURE COAL COMBUSTION KINETICS PROJECT  

SciTech Connect (OSTI)

The HPCCK project was initiated with a kickoff meeting held on June 12, 2001 in Morgantown, WV, which was attended by all project participants. SRI's existing g-RCFR reactor was reconfigured to a SRT-RCFR geometry (Task 1.1). This new design is suitable for performing the NBFZ experiments of Task 1.2. It was decided that the SRT-RCFR apparatus could be modified and used for the HPBO experiments. The purchase, assembly, and testing of required instrumentation and hardware is nearly complete (Task 1.1 and 1.2). Initial samples of PBR coal have been shipped from FWC to SRI (Task 1.1). The ECT device for coal flow measurements used at FWC will not be used in the SRI apparatus and a screw type feeder has been suggested instead (Task 5.1). NEA has completed a upgrade of an existing Fluent simulator for SRI's RCFR to a version that is suitable for interpreting results from tests in the NBFZ configuration (Task 1.3) this upgrade includes finite-rate submodels for devolatilization, secondary volatiles pyrolysis, volatiles combustion, and char oxidation. Plans for an enhanced version of CBK have been discussed and development of this enhanced version has begun (Task 2.5). A developmental framework for implementing pressure and oxygen effects on ash formation in an ash formation model (Task 3.3) has begun.

Chris Guenther; Bill Rogers

2001-09-15T23:59:59.000Z

73

Gas Viscosity at High Pressure and High Temperature  

E-Print Network [OSTI]

. 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...

Ling, Kegang

2012-02-14T23:59:59.000Z

74

Thermodynamics of high-temperature, high-pressure water electrolysis  

Science Journals Connector (OSTI)

Abstract We report on a thermodynamic analysis for water electrolysis from normal conditions (P = 0.1 MPa, T = 298 K) up to heretofore unaddressed temperatures of 1000 K and pressures of 100 MPa. Thermoneutral and reversible potentials are determined using equations-of-state published by the International Association for the Properties of Water and Steam and the National Institute of Standards and Technology. The need for using accurate property models at these elevated temperatures and pressures is exemplified by contrasting results with those obtained via ideal assumptions. The utility of our results is demonstrated by their application in an analysis comparing pressurized electrolysis versus mechanical gas compression. Within the limits of our analysis, pressurized electrolysis demonstrates lower energy requirements albeit with electrical work composing a greater proportion of the total energy input.

Devin Todd; Maximilian Schwager; Walter Mérida

2014-01-01T23:59:59.000Z

75

Low Cost, High Efficiency, High Pressure Hydrogen Storage  

SciTech Connect (OSTI)

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.

Mark Leavitt

2010-03-31T23:59:59.000Z

76

Hydro-Pac Inc., A High Pressure Company  

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

Hydro-Pac Hydro-Pac Inc. A High Pressure Company * Founded in 1972 * Manufacturer of Hydraulically Driven Intensifiers * High Pressure Hydrogen Compressors Hydrogen Compressor Cost Reduction Topics * Standardize Configuration and Fueling Strategy * Simple Designs and Proven Technologies * Identify Economical Hydrogen Compatible Materials * Specify Well Ventilated Sites with Remote Controls Standardize Configuration and Fueling Strategy * Limit the number of compressors and stages * Narrow the range of supply and discharge pressures * Select a flow and standardize Simple Designs and Proven Technologies * Variable speed drives * Double ended intensifiers * Water cooled cylinders * Flexible operational envelopes * Stop and start under load . Material Research / Installation Requirements

77

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

SciTech Connect (OSTI)

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.

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)

2008-06-06T23:59:59.000Z

78

High-Pressure Single-Crystal Techniques  

Science Journals Connector (OSTI)

...systems such as water, methanol, formic acid, oxygen, carbon dioxide and methane...cryostat or a furnace. It is still worth mentioning some older reviews covering...However, due to the high world-market prize of large diamonds and the fact...

Ronald Miletich; David R. Allan; Werner F. Kuhs

79

Experimental Analysis of Water Based Drilling Fluid Aging Processes at High Temperature and High Pressure Conditions  

E-Print Network [OSTI]

! ! EXPERIMENTAL ANALYSIS OF WATER BASED DRILLING FLUID AGING PROCESSES AT HIGH TEMPERATURE AND HIGH PRESSURE CONDITIONS A Thesis by BRANDON SCOTT ZIGMOND Submitted to the Office of Graduate Studies of Texas A&M University... Temperature and High Pressure Conditions Copyright 2012 Brandon Scott Zigmond ! ! EXPERIMENTAL ANALYSIS OF WATER BASED DRILLING FLUID AGING PROCESSES AT HIGH TEMPERATURE AND HIGH PRESSURE CONDITIONS A Thesis by BRANDON SCOTT ZIGMOND Submitted...

Zigmond, Brandon

2012-10-19T23:59:59.000Z

80

Experiment Hazard Class 5.3 High Pressure Vessels  

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

3 High Pressure Vessels 3 High Pressure Vessels Applicability This hazard classification applies to working with pressure vessels and systems. Other hazard classifications and associated controls may apply to experiments in this hazard class. Experiment Category Experiments involving previously reviewed hazard controls are catergorized as medium risk experiments. Experiments involving new equipment, processes or materials, or modified hazard control schemes are categorized as high risk experiments. Hazard Control Plan Verification Statements Engineered Controls - The establishment of applicable controls in accordance with the (American Society of Mechanical Engineers) ASME Boiler and Pressure Code, ASME B.31 Piping Code and applicable federal, state, and local codes. Verify vessel is stampled with ASME Code Symbol or allowable

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


81

Confinement of hydrogen at high pressure in carbon nanotubes  

DOE Patents [OSTI]

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.

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

2011-12-13T23:59:59.000Z

82

Advanced High-Temperature, High-Pressure Transport Reactor Gasification  

SciTech Connect (OSTI)

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)

Michael L. Swanson

2005-08-30T23:59:59.000Z

83

Behavior of silver molybdate at high-pressure  

SciTech Connect (OSTI)

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.

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)

2012-12-15T23:59:59.000Z

84

High-Pressure and High-Temperature Powder Diffraction  

Science Journals Connector (OSTI)

...pressure and varies the motor speed is often used...12.398 is from the quantum mechanical relationship...detectors could in the future reduce data collection...kind of studies in the future. Other more fundamental...addressed in the near future. Temperature gradients...

Yingwei Fei; Yanbin Wang

85

Department of Energy Workshop High Pressure Hydrogen Tank Manufacturing  

E-Print Network [OSTI]

Department of Energy Workshop High Pressure Hydrogen Tank Manufacturing Mark Leavitt Quantum Fuel for integrated module including in-tank regulator · Developed high efficiency H2 fuel storage systems for DOE tank efficiency, the highest weight efficiency ever demonstrated, in partnership with Lawrence

86

Ultra-high pressure water jet: Baseline report  

SciTech Connect (OSTI)

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.

NONE

1997-07-31T23:59:59.000Z

87

High Temperature, High Pressure Devices for Zonal Isolation in Geothermal Wells  

Broader source: Energy.gov [DOE]

DOE Geothermal Peer Review 2010 - Presentation. Project objectives: Design, demonstrate, and qualify high-temperature high pressure zonal isolation devices compatible with the high temperature downhole Enhanced Geothermal Systems (EGS) environment.

88

A high-pressure nanoimaging breakthrough | Argonne National Laboratory  

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

Science Science Computing, Environment & Life Sciences Energy Engineering & Systems Analysis Photon Sciences Physical Sciences & Engineering Energy Frontier Research Centers Science Highlights Postdoctoral Researchers A high-pressure nanoimaging breakthrough July 16, 2013 Tweet EmailPrint A team of researchers made a major breakthrough in measuring the structure of nanomaterials under extremely high pressures. Bragg coherent x-ray diffraction imaging (CXDI) is a promising tool to probe the internal strains of nanometer-sized crystals. But for high-pressure studies the x-ray beam must pass through a component of the diamond anvil cell, which can significantly affect the coherence properties of the beam. The researchers have developed a technique to deal with this that could lead to

89

An experimental investigation of high temperature, high pressure paper drying  

E-Print Network [OSTI]

CONCLUSIONS RECOMMENDATIONS 50 51 REFERENCES APPENDIX A EXPERIMENTAL DATA 52 54 VITA 105 vail LIST OF FIGURES Page Fig. 1 Schematic of test facility 13 Fig. 2 Comparison of Texas A&M drying facility operating ranges to other drying processes... of number of drying passes for drying temperatures of 93, 149, and 204 'C (200, 300, and 400 'F), a contact pressure of 1. 4 MPa (200 psi), a basis weight of 25 g/m' (0. 005 lb/ft'), and contact times between 20 to 180 msec with same side drying...

Patel, Kamal Raoji

2012-06-07T23:59:59.000Z

90

Iterative Boltzmann plot method for temperature and pressure determination in a xenon high pressure discharge lamp  

SciTech Connect (OSTI)

The Boltzmann plot method allows to calculate plasma temperatures and pressures if absolutely calibrated emission coefficients of spectral lines are available. However, xenon arcs are not very well suited to be analyzed this way, as there are only a limited number of lines with atomic data available. These lines have high excitation energies in a small interval between 9.8 and 11.5 eV. Uncertainties in the experimental method and in the atomic data further limit the accuracy of the evaluation procedure. This may result in implausible values of temperature and pressure with inadmissible uncertainty. To omit these shortcomings, an iterative scheme is proposed that is making use of additional information about the xenon fill pressure. This method is proved to be robust against noisy data and significantly reduces the uncertainties. Intentionally distorted synthetic data are used to illustrate the performance of the method, and measurements performed on a laboratory xenon high pressure discharge lamp are analyzed resulting in reasonable temperatures and pressures with significantly reduced uncertainties.

Zalach, J.; Franke, St. [INP Greifswald, Felix-Hausdorff-Str. 2, 17489 Greifswald (Germany)

2013-01-28T23:59:59.000Z

91

Microhole High-Pressure Jet Drill for Coiled Tubing  

SciTech Connect (OSTI)

Tempress Small Mechanically-Assisted High-Pressure Waterjet Drilling Tool project centered on the development of a downhole intensifier (DHI) to boost the hydraulic pressure available from conventional coiled tubing to the level required for high-pressure jet erosion of rock. We reviewed two techniques for implementing this technology (1) pure high-pressure jet drilling and (2) mechanically-assisted jet drilling. Due to the difficulties associated with modifying a downhole motor for mechanically-assisted jet drilling, it was determined that the pure high-pressure jet drilling tool was the best candidate for development and commercialization. It was also determined that this tool needs to run on commingled nitrogen and water to provide adequate downhole differential pressure and to facilitate controlled pressure drilling and descaling applications in low pressure wells. The resulting Microhole jet drilling bottomhole assembly (BHA) drills a 3.625-inch diameter hole with 2-inch coil tubing. The BHA consists of a self-rotating multi-nozzle drilling head, a high-pressure rotary seal/bearing section, an intensifier and a gas separator. Commingled nitrogen and water are separated into two streams in the gas separator. The water stream is pressurized to 3 times the inlet pressure by the downhole intensifier and discharged through nozzles in the drilling head. The energy in the gas-rich stream is used to power the intensifier. Gas-rich exhaust from the intensifier is conducted to the nozzle head where it is used to shroud the jets, increasing their effective range. The prototype BHA was tested at operational pressures and flows in a test chamber and on the end of conventional coiled tubing in a test well. During instrumented runs at downhole conditions, the BHA developed downhole differential pressures of 74 MPa (11,000 psi, median) and 90 MPa (13,000 psi, peaks). The median output differential pressure was nearly 3 times the input differential pressure available from the coiled tubing. In a chamber test, the BHA delivered up to 50 kW (67 hhp) hydraulic power. The tool drilled uncertified class-G cement samples cast into casing at a rate of 0.04 to 0.17 m/min (8 to 33 ft/hr), within the range projected for this tool but slower than a conventional PDM. While the tool met most of the performance goals, reliability requires further improvement. It will be difficult for this tool, as currently configured, to compete with conventional positive displacement downhole motors for most coil tubing drill applications. Mechanical cutters on the rotating nozzle head would improve cutting. This tool can be easily adapted for well descaling operations. A variant of the Microhole jet drilling gas separator was further developed for use with positive displacement downhole motors (PDM) operating on commingled nitrogen and water. A fit-for-purpose motor gas separator was designed and yard tested within the Microhole program. Four commercial units of that design are currently involved in a 10-well field demonstration with Baker Oil Tools in Wyoming. Initial results indicate that the motor gas separators provide significant benefit.

Ken Theimer; Jack Kolle

2007-06-30T23:59:59.000Z

92

Chapter 3 - High-Pressure Processing of Meats and Seafood  

Science Journals Connector (OSTI)

Abstract Meat and seafood products represent a high proportion of the applications of high-pressure processing (HPP) in the world. Mainly used for decontamination purposes, this innovative process has proved to be a reliable technology for ensuring food safety and extending the shelf life of these perishable and fragile foods. However, meat and seafood may experience quality alterations under pressure. This chapter focuses on the effect of HPP on meat and seafood organoleptic quality (texture, color, aroma, taste…). The physicochemical processes responsible for these changes are also reviewed to provide a better understanding of the mechanisms involved. This chapter ends with an overview of current commercial applications and other potential applications.

Frédérique Duranton; Hélène Simonin; Claire Guyon; Stéphanie Jung; Marie de Lamballerie

2014-01-01T23:59:59.000Z

93

Capillary toroid cavity detector for high pressure NMR  

DOE Patents [OSTI]

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.

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)

2007-09-11T23:59:59.000Z

94

Ultra-high pressure water jet: Baseline report; Summary  

SciTech Connect (OSTI)

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.

NONE

1997-07-31T23:59:59.000Z

95

High Temperature, High Pressure Devices for Zonal Isolation in...  

Open Energy Info (EERE)

remotely and autonomous deployable structures for space and our high temperature composite technology developed for downhole applications. These devices offer several...

96

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

E-Print Network [OSTI]

will work only if the cliange in deflectiou due to tenrperature ivas constant for all pressures. which is uot the case. At 0 ksi, the rliaphragni deflection is constant (zerol for all possible temperatures. At 40 ksi. however, the deflection is much... temperature. 3, 3 Basic Dimensioning After selecting the basic configuration and material for the transclucer body a diaphragm cap, it ivas next necessary to determine the actual defle& tion of the diaphragni and any thermally induced affects. Prior to a...

Lippka, Sandra Margaret

1991-01-01T23:59:59.000Z

97

Combined technologies enable high-pressure slickline work  

SciTech Connect (OSTI)

Operators conducting wireline operations can combine the attributes of the slickline grease head and conventional stuffing box to enable work in gas wells at wellhead pressures above 15,000 psi. Wireline/slickline work in high-pressure wells requires meeting the dual challenges of well control and freedom of movement (up and down) for the lines. In a notable application of the combined-technology technique, an operator offshore Louisiana attempted to conduct wireline operations in an 18,000-ft gas and condensate well with 15,600 psi wellhead pressure, using a standard slickline stuffing box to contain the pressure. The standard equipment could not perform the needed function, which involved several trips to depths of 5,000 ft and 18,000 ft. Using a combined-technology, flow-tube stuffing box, the operator was able to conduct the wireline operation without incident; the control arrangement resulted in use of only 3 gal of lubricating oil throughout the job. Post-job analysis of the packing showed only the minimal wear normally associated with low-pressure wireline operations. Although slickline work can be performed in low-pressure gas wells without using the flow-tube stuffing box, the device and the oil used with it isolate the stuffing-box packing from the dry gases, reducing friction swell. This isolation speeds up the operation and reduces packing wear.

Davis, G. [Halliburton Energy Services Inc., Dallas, TX (United States); West, T. [Halliburton Energy Services Inc., Houma, LA (United States)

1998-10-01T23:59:59.000Z

98

High-pressure EXAFS measurements of solid and liquid Kr  

Science Journals Connector (OSTI)

X-ray-absorption measurements of liquid and solid krypton at room temperature in the pressure range 0.1–30 GPa have been performed using the dispersive setup and diamond-anvil cells as a pressure device. The evolution of the near-edge structures as a function of pressure, including the first intense resonance, has been interpreted using multiple-scattering calculations. It is shown that the near-edge structures are reproduced taking into account two-body and three-body terms associated with the first-neighbor atoms. Extended x-ray-absorption fine-structure (EXAFS) spectra have been analyzed in the framework a multiple-scattering data-analysis approach taking proper account of the atomic background including the [1s4p], [1s3d], and [1s3p] double-electron excitation channels. Isobaric Monte Carlo (MC) computer simulations based on empirical pair potentials, as proposed by Barker (K2) and Aziz (HFD-B), have been performed to make a quantitative comparison of theoretical and experimental local structural details of condensed krypton at high pressures. From the analysis of EXAFS data we were able to obtain simultaneous information on average distance, width, and asymmetry of the first-neighbor distribution, as a function of pressure. These parameters yield a unique insight on the potential function because they are affected by both minimum position and curvature of the effective pair potential. The trend of the first-neighbor distribution as a function of pressure is in quantitative agreement with the HFD-B potential at moderate pressures, deviations are found at higher pressures where EXAFS spectra are very sensitive to the hard-core repulsive part of the potential. The weak EXAFS signal of liquid krypton at room temperature and 0.75 GPa has been found in accord with the results of the MC simulations within the noise of the measurement. © 1996 The American Physical Society.

A. Di Cicco; A. Filipponi; J. P. Itié; A. Polian

1996-10-01T23:59:59.000Z

99

Pre-Inspection Checklist for High Pressure Boilers  

E-Print Network [OSTI]

Notice: This checklist reflects the most common violations our field inspectors encounter when performing an inspection on a high-pressure steam boiler installation. It’s suggested that boiler industry personnel have access to a current set of applicable codebooks/jurisdictional laws. Such as: Section I of the ASME Boiler Code:

unknown authors

100

Surface roughening of superalloys by high pressure pure waterjet  

SciTech Connect (OSTI)

A high pressure waterjet has been used to study the surface roughening of superalloys as preparation for thermal spraying. Designed experiments for Mar-M 509 and Rene 80 were carried out for the effects of jet pressure and mass of water delivered per unit area. Comparisons were made of several superalloys in terms of erosion, surface roughness and topology. The mechanism of jet erosion of Rene 80 was studied in relation to its metallurgical microstructure. An MCrAlY coating by shrouded plasma spray was made over a waterjet prepared surface with excellent bonding and having an ideally clean interface.

Taylor, T.A. [Praxair Surface Technologies Inc., Indianapolis, IN (United States)

1995-12-31T23:59:59.000Z

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


101

A New Scanning Tunneling Microscope Reactor Used for High Pressure and High Temperature Catalysis Studies  

SciTech Connect (OSTI)

We present the design and performance of a home-built high-pressure and high-temperature reactor equipped with a high-resolution scanning tunneling microscope (STM) for catalytic studies. In this design, the STM body, sample, and tip are placed in a small high pressure reactor ({approx}19 cm{sup 3}) located within an ultrahigh vacuum (UHV) chamber. A sealable port on the wall of the reactor separates the high pressure environment in the reactor from the vacuum environment of the STM chamber and permits sample transfer and tip change in UHV. A combination of a sample transfer arm, wobble stick, and sample load-lock system allows fast transfer of samples and tips between the preparation chamber, high pressure reactor, and ambient environment. This STM reactor can work as a batch or flowing reactor at a pressure range of 10{sup -13} to several bars and a temperature range of 300-700 K. Experiments performed on two samples both in vacuum and in high pressure conditions demonstrate the capability of in situ investigations of heterogeneous catalysis and surface chemistry at atomic resolution at a wide pressure range from UHV to a pressure higher than 1 atm.

Tao, Feng; Tang, David C.; Salmeron, Miquel; Somorjai, Gabor A.

2008-05-12T23:59:59.000Z

102

High Pressure Burn Rate Measurements on an Ammonium Perchlorate Propellant  

SciTech Connect (OSTI)

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 kPSI). Previous studies on similar AP based materials demonstrate that low pressure (e.g. P < 10 MPa or 1500 PSI) burn rates can be quite different than the elevated pressure deflagration rate measurements (see References and HPP results discussed herein), hence elevated pressure measurements are necessary in order understand the deflagration behavior under relevant conditions. Previous work on explosives have shown that at 100's of MPa some explosives will transition from a laminar burn mechanism to a convective burn mechanism in a process termed deconsolidative burning. The resulting burn rates that are orders-of-magnitude faster than the laminar burn rates. Materials that transition to the deconsolidative-convective burn mechanism at elevated pressures have been shown to be considerably more violent in confined heating experiments (i.e. cook-off scenarios). The mechanisms of propellant and explosive deflagration are extremely complex and include both chemical, and mechanical processes, hence predicting the behavior and rate of a novel material or formulation is difficult if not impossible. In this work, the AP/HTPB based material, TAL-1503 (B-2049), was burned in a constant volume apparatus in argon up to 300 MPa (ca. 44 kPSI). The burn rate and pressure were measured in-situ and used to calculate a pressure dependent burn rate. In general, the material appears to burn in a laminar fashion at these elevated pressures. The experiment was reproduced multiple times and the burn rate law using the best data is B = (0.6 {+-} 0.1) x P{sup (1.05{+-}0.02)} where B is the burn rate in mm/s and P is the pressure in units of MPa. Details of the experimental method, results and data analysis are discussed herein and briefly compared to other AP based materials that have been measured in this apparatus.

Glascoe, E A; Tan, N

2010-04-21T23:59:59.000Z

103

Modified approaches for high pressure filtration of fine clean coal  

SciTech Connect (OSTI)

Removal of moisture from fine (minus 28 mesh) clean coal to 20% or lower level is difficult using the conventional vacuum dewatering technique. High pressure filtration technique provides an avenue for obtaining low moisture in fine clean coal. This paper describes a couple of novel approaches for dewatering of fine clean coal using pressure filtration which provides much lower moisture in fine clean coal than that obtained using conventional pressure filter. The approaches involve (a) split stream dewatering and (b) addition of paper pulp to the coal slurry. For Pittsburgh No. 8 coal slurry, split stream dewatering at 400 mesh provided filter cake containing 12.9% moisture compared to 24.9% obtained on the feed material. The addition of paper pulp to the slurry provided filter cake containing about 17% moisture.

Yang, J.; Groppo, J.G.; Parekh, B.K. [Center for Applied Energy Research, Lexington, KY (United States)

1995-12-31T23:59:59.000Z

104

High resolution ion Doppler spectroscopy at Prairie View Rotamak  

SciTech Connect (OSTI)

A fast ion Doppler spectroscopy (IDS) diagnostic system is installed on the Prairie View Rotamak to measure ion temperature and plasma flow. The diagnostic employs a single channel photomultiplier tube and a Jarrell-Ash 50 monochromator with a diffraction grating line density of 1180 lines/mm, which allows for first order spectra of 200-600 nm. The motorized gear of the monochromator allows spectral resolution of 0.01 nm. Equal IDS measurements are observed for various impurity emission lines of which carbon lines exhibit stronger intensities. Furthermore, the diagnostics is examined in an experiment where plasma experiences sudden disruption and quick recovery. In this case, the IDS measurements show {approx}130% increase in ion temperature. Flow measurements are shown to be consistent with plasma rotation.

Houshmandyar, Saeid; Yang Xiaokang [Solar Observatory Department, Prairie View A and M University, Prairie View, Texas 77446 (United States); Magee, Richard [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

2012-10-15T23:59:59.000Z

105

Advanced High-Temperature, High-Pressure Transport Reactor Gasification  

SciTech Connect (OSTI)

The U.S. Department of Energy (DOE) National Energy Technology Laboratory Office of Coal and Environmental Systems has as its mission to develop advanced gasification-based technologies for affordable, efficient, zero-emission power generation. These advanced power systems, which are expected to produce near-zero pollutants, are an integral part of DOE's Vision 21 Program. DOE has also been developing advanced gasification systems that lower the capital and operating costs of producing syngas for chemical production. A transport reactor has shown potential to be a low-cost syngas producer compared to other gasification systems since its high-throughput-per-unit cross-sectional area reduces capital costs. This work directly supports the Power Systems Development Facility utilizing the KBR transport reactor located at the Southern Company Services Wilsonville, Alabama, site. Over 2800 hours of operation on 11 different coals ranging from bituminous to lignite along with a petroleum coke has been completed to date in the pilot-scale transport reactor development unit (TRDU) at the Energy & Environmental Research Center (EERC). The EERC has established an extensive database on the operation of these various fuels in both air-blown and oxygen-blown modes utilizing a pilot-scale transport reactor gasifier. This database has been useful in determining the effectiveness of design changes on an advanced transport reactor gasifier and for determining the performance of various feedstocks in a transport reactor. The effects of different fuel types on both gasifier performance and the operation of the hot-gas filter system have been determined. It has been demonstrated that corrected fuel gas heating values ranging from 90 to 130 Btu/scf have been achieved in air-blown mode, while heating values up to 230 Btu/scf on a dry basis have been achieved in oxygen-blown mode. Carbon conversions up to 95% have also been obtained and are highly dependent on the oxygen-coal ratio. Higher-reactivity (low-rank) coals appear to perform better in a transport reactor than the less reactive bituminous coals. Factors that affect TRDU product gas quality appear to be coal type, temperature, and air/coal ratios. Testing with a higher-ash, high-moisture, low-rank coal from the Red Hills Mine of the Mississippi Lignite Mining Company has recently been completed. Testing with the lignite coal generated a fuel gas with acceptable heating value and a high carbon conversion, although some drying of the high-moisture lignite was required before coal-feeding problems were resolved. No ash deposition or bed material agglomeration issues were encountered with this fuel. In order to better understand the coal devolatilization and cracking chemistry occurring in the riser of the transport reactor, gas and solid sampling directly from the riser and the filter outlet has been accomplished. This was done using a baseline Powder River Basin subbituminous coal from the Peabody Energy North Antelope Rochelle Mine near Gillette, Wyoming.

Michael Swanson; Daniel Laudal

2008-03-31T23:59:59.000Z

106

Thermodynamic properties of hydrocarbon liquids at high pressures and temperatures  

SciTech Connect (OSTI)

Understanding the organic/inorganic interface in the Earth's crust requires values of the thermodynamic properties of hydrocarbon species in crude oil, coal, and natural gas at elevated temperatures and pressures. Values of the apparent standard partial molal Gibbs free energies and enthalpies of formation and the standard partial molal entropies and heat capacities of these organic species can be computed as a function of temperature at 1 bar using the equations of state adopted by Helgeson et al (1991). The pressure dependence of the thermodynamic properties can be calculated from a modified version of the Parameters From Group Contributions (PFGC) equation of state. To improve the accuracy of these predictions, critical evaluation of high-pressure density experiments reported in the literature was used in the present study to characterize b[sub j] as a function of pressure and temperature. The revised PFGC equation of state permits accurate calculation of the standard partial molal volumes of the major hydrocarbon species in the aliphatic, aromatic, and naphthenic fractions of crude oil, as well as fatty acids, phenols, and naphthenic acids at temperatures and pressures to 500 C and 5 kbar. Combining the revised PFGC equation of state and parameters with the standard partial molal properties of these species at one bar and those of aqueous species and minerals permits calculation of the apparent standard partial molal Gibbs Free energies of reaction, and thus equilibrium constants for a wide variety of chemical equilibria among organic liquids, solids, and gases, aqueous species, and minerals at temperatures and pressures characteristic of both diagenetic and low-grade metamorphic processes in the Earth's crust.

Aagaard, P. (Univ. of Oslo (Norway). Dept. of Geology); Oelkers, E.H. (Univ. Paul Sabatier, Toulouse (France). Lab. de Geochimie); Helgeson, H.C. (Univ. of California, Berkeley, CA (United States). Dept. of Geology and Geophysics)

1992-01-01T23:59:59.000Z

107

High pressure liquid chromatographic method for CP amide analysis  

SciTech Connect (OSTI)

A method has been developed for the analysis of the 5-carboxamidotetrazolatopentaamminecobalt(III) perchlorate contaminant of the explosive CP (2-(5-cyanotetrazolato)-pentaamminecobalt(III) perchlorate). The analysis utilizes a Zn/Hg reduction of the cobalt (III) complexes to allow a high pressure liquid chromatographic (HPLC) analysis of the reaction products; the product analysis is directly related to the weight percent of impurity present in the explosive. The technique is described and shortcomings pointed out.

Loyola, V. M.; Womelsduff, J. E.

1981-02-01T23:59:59.000Z

108

Inelastic neutron scattering from single crystal Zn under high pressure  

Science Journals Connector (OSTI)

Inelastic neutron-scattering experiments have been performed for single crystals of Zn under pressures up to 8.8 GPa at 300 K. The phonon modes q/qmax=?=0.075 and ?=0.10 were measured in the transverse acoustic branch ?3, where q=0 corresponds with the elastic constant C44. The phonon energy showed a substantial hardening with increasing pressure. The experimental data below 6.8 GPa for ?=0.075 yield a constant Grüneisen mode ?i=-ln?i/lnV of 2.25 in good agreement with a previous calculation [H. Ledbetter, Phys. Status Solidi B 181, 81 (1994)]. Above 6.8 GPa, there is a very rapid increase of ?i which is indicative of the presence of a giant Kohn anomaly. This rapid divergence at high pressure indicates that a phonon softening may occur at pressures higher than 8.8 GPa caused by the collapse of the giant Kohn anomaly via an electronic topological transition (ETT). In an earlier Mössbauer Zn study at 4 K [W. Potzel et al., Phys. Rev. Lett. 74, 1139 (1994)], a drastic drop of the Lamb-Mössbauer factor was observed at 6.6 GPa, which was interpreted as being due to phonon softening, indicating this ETT had occurred. This paper also compares the compressibility data for single crystal Zn and Zn powder using neutron scattering. The results were found to be similar to an earlier x-ray Zn powder experiment [O. Schulte et al., High Pressure Res. 6, 169 (1991)]. © 1996 The American Physical Society.

J. G. Morgan; R. B. Von Dreele; P. Wochner; S. M. Shapiro

1996-07-01T23:59:59.000Z

109

A High Pressure Carbon Dioxide Separation Process for IGCC Plants  

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

High Pressure Carbon Dioxide Separation Process for IGCC Plants High Pressure Carbon Dioxide Separation Process for IGCC Plants 1 A High Pressure Carbon Dioxide Separation Process for IGCC Plants S.S. Tam 1 , M.E. Stanton 1 , S. Ghose 1 , G. Deppe 1 , D.F. Spencer 2 , R.P. Currier 3 , J.S. Young 3 , G.K. Anderson 3 , L.A. Le 3 , and D.J. Devlin 3 1 Nexant, Inc. (A Bechtel Technology & Consulting Company) 45 Fremont St., 7 th Fl., San Francisco, CA 94506 2 SIMTECHE 13474 Tierra Heights Road, Redding, CA 96003 3 Los Alamos National Laboratory P.O. Box 1663 (MS J567), Los Alamos, NM 87545 1.0 INTRODUCTION Under separate contracts from the U.S. Department of Energy, Office of Fossil Energy (DOE- FE), Los Alamos National Laboratory, and a team of SIMTECHE and Nexant (a Bechtel Technology and Consulting Company) are jointly working to develop the proprietary process for

110

Toroid cavities as NMR detectors in high pressure probes  

SciTech Connect (OSTI)

A cylindrical toroid cavity has been developed for application as an NMR detector for high sensitivity and high resolution spectroscopy in metal vessel probes. Those probes are used for in situ investigations at high temperature and pressure. Since the transmitted r.f. field is completely confined within the torus, the cavity can be placed inside the pressurized system without magnetic coupling to the metal vessel. Resonance frequencies up to 400 MHz make the toroid cavity detector especially suited for use in {sup 1}H and {sup 19}F spectroscopy. Typically achieved static {sup 1}H linewidths, measured on CHCl{sub 3} using cavities in Be-Cu pressure vessels, are 2.0 Hz. On the basis of theoretical considerations that include the radial dependence of the r.f. field within cylindrical or circular toroid detectors, equations were evolved to predict the signal intensity as a function of the pulse width. The equations precisely describe the deviations from the sinusoidal approximation, which is generally used for signal intensities derived from Helmholtz or solenoid coils.

Woelk, K.; Rathke, J.W.; Klingler, R.J.

1993-03-01T23:59:59.000Z

111

Early View (EV): 1-EV High connectivity among habitats precludes the relationship  

E-Print Network [OSTI]

Early View (EV): 1-EV High connectivity among habitats precludes the relationship between dispersal such as currents and larval behaviors (reviewed in Mora and Sale 2002), the use of PLD as a quantitative measure

Roy, Denis

112

Devices and process for high-pressure magic angle spinning nuclear magnetic resonance  

DOE Patents [OSTI]

A high-pressure magic angle spinning (MAS) rotor is detailed that includes a high-pressure sample cell that maintains high pressures exceeding 150 bar. The sample cell design minimizes pressure losses due to penetration over an extended period of time.

Hoyt, David W; Sears, Jr., Jesse A; Turcu, Romulus V.F.; Rosso, Kevin M; Hu, Jian Zhi

2014-04-08T23:59:59.000Z

113

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

SciTech Connect (OSTI)

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 {approx} 400 C temperature range. We believe that the sample commenced in the {alpha}-phase and then ended up in an amorphous phase when the temperature increased beyond 280 C near 2 GPa, which we believe to be the {gamma}-phase. Further pressure and temperature cycling suggests that the sample transformed reversibly into and out of the amorphous phase near the phase line.

Pravica, Michael; Galley, Martin; Park, Changyong; Ruiz, Harrison; Wojno, Jennifer (UNLV); (CIW)

2012-08-29T23:59:59.000Z

114

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

E-Print Network [OSTI]

are multiple diaphragms attached at the edges. Flat and corrugated diaphragms are discussed at length by Giovanni (1982). The three most common detection systems are strain gauges, capacitance gauges, and linear variable differential transformers (LVDT... be necessary to connect the resistor and ratio transformer to. the same secondary coil to balance the voltage of the . two secondary coils. Samplers Inlet Inert Fluid Inlet Pressure Housing Electrical Feedthrough LVDT Coils Magnetic Core Pressure...

Childers, Laren Paul

1984-01-01T23:59:59.000Z

115

Ground-State Structures of Ice at High-Pressures  

E-Print Network [OSTI]

\\textit{Ab initio} random structure searching based on density functional theory is used to determine the ground-state structures of ice at high pressures. Including estimates of lattice zero-point energies, ice is found to adopt three novel crystal phases. The underlying sub-lattice of O atoms remains similar among them, and the transitions can be characterized by reorganizations of the hydrogen bonds. The symmetric hydrogen bonds of ice X and $Pbcm$ are initially lost as ice transforms to structures with symmetries $Pmc2_1$ (800 - 950 GPa) and $P2_1$ (1.17 TPa), but they are eventually regained at 5.62 TPa in a layered structure $C2/m$. The $P2_1 \\rightarrow C2/m$ transformation also marks the insulator-to-metal transition in ice, which occurs at a significantly higher pressure than recently predicted.

McMahon, Jeffrey M

2011-01-01T23:59:59.000Z

116

High pressure generation by hot electrons driven ablation  

SciTech Connect (OSTI)

A previous model [Piriz et al. Phys. Plasmas 19, 122705 (2012)] for the ablation driven by the hot electrons generated in collisionless laser-plasma interactions in the framework of shock ignition is revisited. The impact of recent results indicating that for a laser wavelength ? = 0.35 ?m the hot electron temperature ?{sub H} would be independent of the laser intensity I, on the resulting ablation pressure is considered. In comparison with the case when the scaling law ?{sub H}?(I?{sup 2}){sup 1/3} is assumed, the generation of the high pressures needed for driving the ignitor shock may be more demanding. Intensities above 10{sup 17} W/cm{sup 2} would be required for ?{sub H}=25?30 keV.

Piriz, A. R. [E.T.S.I. Industriales, CYTEMA, and Instituto de Investigaciones Energéticas, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain)] [E.T.S.I. Industriales, CYTEMA, and Instituto de Investigaciones Energéticas, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Piriz, S. A. [Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid (Spain)] [Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid (Spain); Tahir, N. A. [GSI Helmholtzzentrum für Schwerionenforschung, Planckstrasse 1, 64291 Darmstadt (Germany)] [GSI Helmholtzzentrum für Schwerionenforschung, Planckstrasse 1, 64291 Darmstadt (Germany)

2013-11-15T23:59:59.000Z

117

A diamond-window XAFS cell for studies of high-temperature, high-pressure aqueous solutions  

SciTech Connect (OSTI)

We describe a method to collect x-ray absorption fine structure (XAFS) spectra of ions in a supercritical water solvent. Supercritical water (SCW), at temperatures above water{close_quote}s critical point of 374{degree}C, is an interesting solvent for chemical reactions and hazardous waste destruction due to the high solubility of organics and the aggressive oxidizing environment. XAFS may provide a better understanding of the solvent environment in SCW. The XAFS cell used in these studies was composed of a block of high-nickel alloy, Hastelloy C-22, containing two windows for transmission of the x-ray beam and a single optical view window. All internal wetted surfaces were platinum plated. The maximum operating conditions for this design were 500{degree}C and 700 bar. The x-ray transmission windows consisted of CVD (chemical vapor deposition) diamond windows (3 mm diameter {times}0.5 mm thick) that were brazed to the tip of a standard 1/4-in. high-pressure, coned-shape fitting. Spectra are reported for strontium and rubidium ions in a supercritical water solvent. This cell design could be used for a variety of other solvent systems at high temperatures and high pressures. {copyright} {ital 1996 American Institute of Physics.}

Fulton, J.L.; Pfund, D.M. [Chemical Sciences Department, Pacific Northwest Laboratory, Richland, WA 99352 (United States)] [Chemical Sciences Department, Pacific Northwest Laboratory, Richland, WA 99352 (United States); Ma, Y. [Brookhaven National Laboratory, Bldg 510 E, Upton, NY 11973 (United States)] [Brookhaven National Laboratory, Bldg 510 E, Upton, NY 11973 (United States)

1996-09-01T23:59:59.000Z

118

FRICTION FACTOR IN HIGH PRESSURE NATURAL GAS PIPELINES FROM ROUGHNESS MEASUREMENTS  

E-Print Network [OSTI]

FRICTION FACTOR IN HIGH PRESSURE NATURAL GAS PIPELINES FROM ROUGHNESS MEASUREMENTS DETERMINATION DU and Technology, Norway ABSTRACT Pressure drop experiments on natural gas flow at 80 to 120 bar pressure and high of natural gas at typical operating pressures (100-180 bar). At such Reynolds numbers the classical Colebrook

Gudmundsson, Jon Steinar

119

High pressure studies on nanometer sized clusters: Structural, optical, and cooperative properties  

SciTech Connect (OSTI)

High-pressure Se EXAFS is used to study pressure-induced structural transformations in CdSe nanocrystals. The transformation is wurtzite to rock salt, at a pressure much higher than in bulk. High-pressure XRD is used to confirm the EXAFS results. Diffraction peak widths indicate that nanocrystals do not fragment upon transformation. Optical absorption correlates with structural transformations and is used to measure transition pressures; transformation pressure increases smoothly as nanocrystal size decreases. Thermodynamics of transformation is modeled using an elevated surface energy in the high-pressure phase. High-pressure study of Si nanocrystals show large increases in transformation pressure in crystallites to 500{angstrom} diameter, and an overall change in crystallite shape upon transformation is seen from XRD line widths. C{sub 60} single crystals were studied using Raman scattering; results provide information about the clusters` rotational state. Optical properties of high-pressure phase CdSe clusters were studied.

Tolbert, S.H.

1995-05-01T23:59:59.000Z

120

Development of optimal diaphragm-based pulsation damper structure for high-pressure GDI pump systems through design of experiments  

Science Journals Connector (OSTI)

This study optimizes the profile of the diaphragms of the pressure pulsation damper structure in a high-pressure GDI pump system that is now under development by applying the design of experiments (DOE) method. Because a high-pressure pulsation ranging from 0 to 10 bar reduces the performance of a GDI engine and harms it from a structural point of view, attenuating the large amplitude of the fluid pulsation pressure of the gasoline fuel injected into a GDI pump is necessary. Both the relatively low frequency range of the pressure pulsation, i.e., from 0 Hz to 30 Hz, inside the GDI engine and the high pressure of the utilized gasoline fuel prevent us from applying the existing pressure pulsation dampers such as a T-filter and Helmholtz resonator. Therefore, automotive companies utilize a new pressure pulsation damper structure called an accumulator, which is filled with gas. In the development of this pressure accumulator, it is crucial to design optimal profiles for the enveloping diaphragms in terms of the pulsation efficiency and mechanical stress for the sake of safety. In order to optimize the profile of the diaphragms used in the accumulator developed for a GDI engine, this research develops a new finite element procedure that considers the pressure variation by assuming the isoenthalpy state of the enveloped gas inside the accumulator. The developed finite element procedure is then integrated with the DOE method to determine the optimal profile for the enveloping structure of the developed accumulator. To validate the performance of the developed accumulator, the optimized accumulator is manufactured and tested.

Juyeong Kim; Gil Ho Yoon; Jinyee Noh; Jongwook Lee; Kyungnam Kim; Hyoungjong Park; Jaekeun Hwang; Yeonhong Lee

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high pressures view" from the National Library of EnergyBeta (NLEBeta).
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121

Smart Onboard Inspection of High Pressure Gas Fuel Cylinders  

SciTech Connect (OSTI)

The use of natural gas as an alternative fuel in automotive applications is not widespread primarily because of the high cost and durability of the composite storage tanks. Tanks manufactured using carbon fiber are desirable in weight critical passenger vehicles because of the low density of carbon fiber. The high strength of carbon fiber also translates to a weight reduction because thinner wall designs are possible to withstand the internal pressure loads. However, carbon fiber composites are prone to impact damage that over the life of the storage tank may lead to an unsafe condition for the vehicle operator. A technique that potentially may be a reliable indication of developing hazardous conditions in composite fuel tanks is imbedded fiber optics. The applicability of this technique to onboard inspection is discussed and results from preliminary lab testing indicate that fiber optic sensors can reliably detect impact damage.

Beshears, D.L.; Starbuck, J.M.

1999-09-27T23:59:59.000Z

122

Laves phase hydrogen storage alloys for super-high-pressure metal hydride hydrogen compressors  

Science Journals Connector (OSTI)

Ti-Cr- and Ti-Mn-based alloys were prepared to be low- and high-pressure stage metals for a double-stage super-high-pressure metal hydride hydrogen compressor. Their crystallographic characteristics and hydrogen

Xiumei Guo; Shumao Wang; Xiaopeng Liu; Zhinian Li; Fang Lü; Jing Mi; Lei Hao…

2011-06-01T23:59:59.000Z

123

Electrical conductivity of wadsleyite at high temperatures and high pressures Lidong Dai a,b  

E-Print Network [OSTI]

Electrical conductivity of wadsleyite at high temperatures and high pressures Lidong Dai a,b , Shun 2009 Editor: L. Stixrude Keywords: electrical conductivity wadsleyite oxygen fugacity frequency water The electrical conductivity of wadsleyite aggregates has been determined under the broad range of thermodynamic

124

Detecting and modeling cement failure in high pressure/ high temperature wells using finite-element method  

E-Print Network [OSTI]

. In the event that high-pressure and high-temperature (HPHT) conditions are encountered, we must attempt to achieve permeability in the set cement to prevent gas migration and to prevent any other fluid passing through to collapse the entire structure. Therefore...

Shahri, Mehdi Abbaszadeh

2006-04-12T23:59:59.000Z

125

X-ray reflectivity measurements of liquid/solid interfaces under high hydrostatic pressure conditions  

Science Journals Connector (OSTI)

A high hydrostatic pressure cell for X-ray reflectivity measurements at the solid/liquid interface is presented.

Wirkert, F.J.

2013-11-02T23:59:59.000Z

126

High- and low-temperature-stable thermite composition for producing high-pressure, high-velocity gases  

DOE Patents [OSTI]

A high- and low-temperature-stable thermite composition for producing high-pressure and high-velocity gases comprises an oxidizable metal, an oxidizing reagent, and a high-temperature-stable gas-producing additive selected from the group consisting of metal carbides and metal nitrides.

Halcomb, Danny L. (Camden, OH); Mohler, Jonathan H. (Spring Valley, OH)

1990-10-16T23:59:59.000Z

127

High-pressure coal fuel processor development. Final report  

SciTech Connect (OSTI)

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.

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

1992-12-01T23:59:59.000Z

128

Strategies for laser-induced fluorescence detection of nitric oxide in high-pressure flames.  

E-Print Network [OSTI]

engines and gas turbines where the combustion chamber is at high pressure. Despite the use of catalyticStrategies for laser-induced fluorescence detection of nitric oxide in high-pressure flames. II. A combustion systems3�13 and thus develop new schemes to mini- mize NO effluent. The high operating pressure

Lee, Tonghun

129

A multi-purpose modular system for high-resolution microscopy at high hydrostatic pressure  

E-Print Network [OSTI]

We have developed a modular system for high-resolution microscopy at high hydrostatic pressure. The system consists of a pressurised cell of volume ~100 microlitres, a temperature controlled holder, a ram and a piston. We have made each of these components in several versions which can be interchanged to allow a wide range of applications. Here, we report two pressure cells with pressure ranges 0.1-700MPa and 0.1-100MPa, which can be combined with hollow or solid rams and pistons. Our system is designed to work with fluorescent samples (using a confocal or epifluorescence microscope), but also allows for transmitted light microscopy via the hollow ram and piston. The system allows precise control of pressure and temperature [-20-70C], as well as rapid pressure quenching. We demonstrate its performance and versatility with two applications: time-resolved imaging of colloidal phase transitions caused by pressure changes between 0.1MPa and 101MPa, and imaging the growth of Escherichia coli bacteria at 50MPa. We ...

Vass, Hugh; Herzig, Eva M; Ward, F Bruce; Clegg, Paul S; Allen, Rosalind J

2009-01-01T23:59:59.000Z

130

A High-Pressure Nano-imaging Breakthrough | Advanced Photon Source  

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

Protein Structure Could Lead to Better Treatments for HIV, Early Aging Protein Structure Could Lead to Better Treatments for HIV, Early Aging The Superpower behind Iron Oxyfluoride Battery Electrodes Watching a Protein as it Functions Shedding Light on Chemistry with a Biological Twist Teasing Out the Nature of Structural Instabilities in Ceramic Compounds Science Highlights Archives: 2013 | 2012 | 2011 | 2010 2009 | 2008 | 2007 | 2006 2005 | 2004 | 2003 | 2002 2001 | 2000 | 1998 | Subscribe to APS Science Highlights rss feed A High-Pressure Nano-imaging Breakthrough APRIL 11, 2013 Bookmark and Share Bragg CXDI measurements were performed at 0.8, 1.7, 2.5, 3.2, and 6.4 GPa on the same crystal. The reconstructed images (both top and bottom views) are shown above. From W. Yang et al., Nat. Comm. 4 (2013). A team of researchers has made a major breakthrough in measuring the

131

On the atomic line profiles in high pressure plasmas  

SciTech Connect (OSTI)

In a previous contribution to this journal [H. P. Stormberg, J. Appl. Phys. 51(4), 1963 (1980)], Stormberg presented an analytical expression for the convolution of Lorentz and Levy line profiles, which models atomic radiative transitions in high pressure plasmas. Unfortunately, the derivations are flawed with errors and the final expression, while correct, is accompanied by misguiding comments about the meaning of the symbols used therein, in particular the “complex error function.” In this paper, we discuss the broadening mechanisms that give rise to Stormberg's model and present a correct derivation of his final result. We will also provide an alternative expression, based on the Faddeeva function, which has decisive computational advantages and emphasizes the real-valuedness of the result. The MATLAB/Octave scripts of our implementation have been made available on the publisher's website for future reference.

Janssen, J. F. J.; Gnybida, M.; Rijke, A. J.; Dijk, J. van [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)] [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands); Suijker, J. L. G. [Philips Lighting R and D Category Professional Lamps, P.O. Box 80020, 5600 JM Eindhoven (Netherlands)] [Philips Lighting R and D Category Professional Lamps, P.O. Box 80020, 5600 JM Eindhoven (Netherlands)

2013-11-14T23:59:59.000Z

132

High pressure studies on nanocrystalline aurivillius oxides lead and mercury chalcogenides;.  

E-Print Network [OSTI]

??The high pressure and high temperature play a vital role in newlineunderstanding the physical properties of the solids including such classes of newlinematerials like semiconductors… (more)

Freny joy K M

2015-01-01T23:59:59.000Z

133

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

E-Print Network [OSTI]

, the design did have a 7 Pa sensitivity which is especially imoortant as the sensing transformer was located outside the pressure containment. This feature eliminates the need for electrical feedthroughs which usually limit the operating conditions... was constructed and the sensitivity increased to ? 5 -1 2x10 Pa using the same transformer. Based on the designs tested, a new differential pressure indicator was proposed. Using a diaphragm with a linear variable differential transformer outside the pressure...

Osburn, Douglas Clayton

1981-01-01T23:59:59.000Z

134

The viscosity of liquids (a) Normal octanol at atmospheric pressure (b) An equipment for high pressures.  

E-Print Network [OSTI]

??Theories of Liquid Viscosity lead to equations giving the variation of the viscosity with temperature and pressure, but give poor agreement with experimental values, particularly… (more)

De Verteuil, Georges Francois

2012-01-01T23:59:59.000Z

135

Preconcentrator with high volume chiller for high vapor pressure particle detection  

SciTech Connect (OSTI)

Apparatus and method for collecting particles of both high and low vapor pressure target materials entrained in a large volume sample gas stream. Large volume active cooling provides a cold air supply which is mixed with the sample gas stream to reduce the vapor pressure of the particles. In embodiments, a chiller cools air from ambient conditions to 0-15.degree. C. with the volumetric flow rate of the cold air supply being at least equal to the volumetric flow rate of the sample gas stream. In further embodiments an adsorption media is heated in at least two stages, a first of which is below a threshold temperature at which decomposition products of the high vapor pressure particle are generated.

Linker, Kevin L

2013-10-22T23:59:59.000Z

136

Synthesis, structural characterization and high pressure phase transitions of monolithium hydronium sulfate  

SciTech Connect (OSTI)

A three dimensional lithium hydronium sulfate LiSO{sub 4}{center_dot}H{sub 3}O [1], [space group Pna2{sub 1}a=8.7785(12) A, b=9.1297(12) A, c=5.2799(7) A, V=423.16(10) A{sup 3}] was synthesized via solvothermal methods using 1,5-naphthalenedisulfonic acid (1,5-NSA) as the source of sulfate ions. The structure of [1], determined by single crystal X-ray diffraction techniques, consists of corner sharing LiO{sub 4} and SO{sub 4} tetrahedra, forming an anionic 3-D open framework that is charge balanced by hydronium ions positioned within channels running along [001] and forming strong H-bonding with the framework oxygen atoms. Compound [1] undergoes two reversible phase transitions, involving reorientation of SO{sub 4}{sup 2-} ions at pressures of approximately 2.5 and 5 GPa at room temperature, as evident from characteristic discontinuous frequency drops in the {nu}{sub 1} mode of the Raman spectra. Additionally, compound [1] forms dense {beta}-lithium sulfate at 300 Degree-Sign C, as evident from temperature dependent powder XRD and combined reversible TGA-DSC experiments. - Graphical abstract: Left: View of corner-shared LiO{sub 4} and SO{sub 4} tetrahedra along [001] direction with hydronium ions situated in the channels. Right: (a) Photograph of the loaded DAC (b) Ambient pressure Raman spectrum of compound [1] (c) Evolution of the {nu}{sub 1} mode with the increasing and decreasing pressure indicating transitions to high-pressure phases at {approx}2.5 (red curves) and {approx}5 GPa (blue curves) and at {approx}3.5 GPa upon decompression. Highlights: Black-Right-Pointing-Pointer A 3-D lithium hydronium sulfate is synthesized by solvothermal methods. Black-Right-Pointing-Pointer Two high pressure phase transition occurs due to rotation of sulfate groups. Black-Right-Pointing-Pointer The framework undergoes a high temperature structural transformation, to form {beta}-Li{sub 2}SO{sub 4} phase.

Banerjee, Debasis, E-mail: debasis.banerjee@stonybrook.edu [Department of Chemistry, Stony Brook University, Stony Brook 11794-3400 (United States); Plonka, Anna M. [Department of Geosciences, Stony Brook University, Stony Brook 11794-2100 (United States); Kim, Sun Jin [Nano-Materials Research Center, Korea Institute of Science and Technology, P.O. Box 131, Cheongryang, Seoul 130-650 (Korea, Republic of); Xu Wenqian [Department of Geosciences, Stony Brook University, Stony Brook 11794-2100 (United States); Parise, John B. [Department of Chemistry, Stony Brook University, Stony Brook 11794-3400 (United States); Mineral Physics Institute, Stony Brook University, Stony Brook, NY 11790-2100 (United States)

2013-01-15T23:59:59.000Z

137

High pressure humidification columns: Design equations, algorithm, and computer code  

SciTech Connect (OSTI)

This report describes the detailed development of a computer model to simulate the humidification of an air stream in contact with a water stream in a countercurrent, packed tower, humidification column. The computer model has been developed as a user model for the Advanced System for Process Engineering (ASPEN) simulator. This was done to utilize the powerful ASPEN flash algorithms as well as to provide ease of use when using ASPEN to model systems containing humidification columns. The model can easily be modified for stand-alone use by incorporating any standard algorithm for performing flash calculations. The model was primarily developed to analyze Humid Air Turbine (HAT) power cycles; however, it can be used for any application that involves a humidifier or saturator. The solution is based on a multiple stage model of a packed column which incorporates mass and energy, balances, mass transfer and heat transfer rate expressions, the Lewis relation and a thermodynamic equilibrium model for the air-water system. The inlet air properties, inlet water properties and a measure of the mass transfer and heat transfer which occur in the column are the only required input parameters to the model. Several example problems are provided to illustrate the algorithm`s ability to generate the temperature of the water, flow rate of the water, temperature of the air, flow rate of the air and humidity of the air as a function of height in the column. The algorithm can be used to model any high-pressure air humidification column operating at pressures up to 50 atm. This discussion includes descriptions of various humidification processes, detailed derivations of the relevant expressions, and methods of incorporating these equations into a computer model for a humidification column.

Enick, R.M. [Pittsburgh Univ., PA (United States). Dept. of Chemical and Petroleum Engineering; Klara, S.M. [USDOE Pittsburgh Energy Technology Center, PA (United States); Marano, J.J. [Burns and Roe Services Corp., Pittsburgh, PA (United States)

1994-07-01T23:59:59.000Z

138

High-pressure cell for neutron diffraction with in situ pressure control at cryogenic temperatures  

SciTech Connect (OSTI)

Pressure generation at cryogenic temperatures presents a problem for a wide array of experimental techniques, particularly neutron studies due to the volume of sample required. We present a novel, compact pressure cell with a large sample volume in which load is generated by a bellow. Using a supply of helium gas up to a pressure of 350 bar, a load of up to 78 kN is generated with leak-free operation. In addition, special fiber ports added to the cryogenic center stick allow for in situ pressure determination using the ruby pressure standard. Mechanical stability was assessed using finite element analysis and the dimensions of the cell have been optimized for use with standard cryogenic equipment. Load testing and on-line experiments using NaCl and BiNiO{sub 3} have been done at the WISH instrument of the ISIS pulsed neutron source to verify performance.

Jacobsen, Matthew K.; Ridley, Christopher J.; Bocian, Artur; Kamenev, Konstantin V., E-mail: k.kamenev@ed.ac.uk [School of Engineering and CSEC, University of Edinburgh, Edinburgh (United Kingdom); Kirichek, Oleg; Manuel, Pascal; Khalyavin, Dmitry [ISIS, Rutherford Appleton Laboratory, Harwell Oxford (United Kingdom)] [ISIS, Rutherford Appleton Laboratory, Harwell Oxford (United Kingdom); Azuma, Masaki [Materials and Structures Laboratory, Tokyo Institute of Technology, Tokyo (Japan)] [Materials and Structures Laboratory, Tokyo Institute of Technology, Tokyo (Japan); Attfield, J. Paul [School of Chemistry and CSEC, University of Edinburgh, Edinburgh (United Kingdom)] [School of Chemistry and CSEC, University of Edinburgh, Edinburgh (United Kingdom)

2014-04-15T23:59:59.000Z

139

High Performance Fuel Desing for Next Generation Pressurized Water Reactors  

SciTech Connect (OSTI)

The use of internally and externally cooled annular fule rods for high power density Pressurized Water Reactors is assessed. The assessment included steady state and transient thermal conditions, neutronic and fuel management requirements, mechanical vibration issues, fuel performance issues, fuel fabrication methods and econmic assessment. The investigation was donducted by a team from MIT, Westinghouse, Gamma Engineering, Framatome ANP, and AECL. The analyses led to the conclusion that raising the power density by 50% may be possible with this advanced fuel. Even at the 150% power level, the fuel temperature would be a few hundred degrees lower than the current fuel temperatre. Significant economic and safety advantages can be obtained by using this fuel in new reactors. Switching to this type of fuel for existing reactors would yield safety advantages, but the economic return is dependent on the duration of plant shutdown to accommodate higher power production. The main feasiblity issue for the high power performance appears to be the potential for uneven splitting of heat flux between the inner and outer fuel surfaces due to premature closure of the outer fuel-cladding gap. This could be overcome by using a very narrow gap for the inner fuel surface and/or the spraying of a crushable zirconium oxide film at the fuel pellet outer surface. An alternative fuel manufacturing approach using vobropacking was also investigated but appears to yield lower than desirable fuel density.

Mujid S. Kazimi; Pavel Hejzlar

2006-01-31T23:59:59.000Z

140

Applications of toroids in high-pressure NMR spectroscopy  

SciTech Connect (OSTI)

Toroid detectors have distinct NMR sensitivity and imaging advantages. The magnetic field lines are nearly completely contained within the active volume element of a toroid. This results in high NMR signal sensitivity. In addition, the toroid detector may be placed next to the metallic walls of a containment vessel with minimal signal loss due to magnetic coupling with the metal container. Thus, the toroid detector is ideal for static high pressure or continuous flow monitoring systems. Toroid NMR detectors have been used to follow the hydroformylation of olefins in supercritical fluids under industrial process conditions. Supercritical fluids are potentially ideal media for conducting catalytic reactions that involve gaseous reactants, including H{sub 2}, CO, and CO{sub 2}. The presence of a single homogeneous reaction phase eliminates the gas-liquid mixing problem of alternative two-phase systems, which can limit process rates and adversely affect hydroformylation product selectivities. A second advantage of toroid NMR detectors is that they exhibit a well-defined gradient in the rf field. This magnetic field gradient can be used for NMR imaging applications. Distance resolutions of 20 {mu} have been obtained.

Klingler, R.J.; Rathke, J.W.; Woelk, K. [and others

1995-12-01T23:59:59.000Z

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


141

High Temperature Electrolysis Pressurized Experiment Design, Operation, and Results  

SciTech Connect (OSTI)

A new facility has been developed at the Idaho National Laboratory for pressurized testing of solid oxide electrolysis stacks. Pressurized operation is envisioned for large-scale hydrogen production plants, yielding higher overall efficiencies when the hydrogen product is to be delivered at elevated pressure for tank storage or pipelines. Pressurized operation also supports higher mass flow rates of the process gases with smaller components. The test stand can accommodate planar cells with dimensions up to 8.5 cm x 8.5 cm and stacks of up to 25 cells. It is also suitable for testing other cell and stack geometries including tubular cells. The pressure boundary for these tests is a water-cooled spool-piece pressure vessel designed for operation up to 5 MPa. Pressurized operation of a ten-cell internally manifolded solid oxide electrolysis stack has been successfully demonstrated up 1.5 MPa. The stack is internally manifolded and operates in cross-flow with an inverted-U flow pattern. Feed-throughs for gas inlets/outlets, power, and instrumentation are all located in the bottom flange. The entire spool piece, with the exception of the bottom flange, can be lifted to allow access to the internal furnace and test fixture. Lifting is accomplished with a motorized threaded drive mechanism attached to a rigid structural frame. Stack mechanical compression is accomplished using springs that are located inside of the pressure boundary, but outside of the hot zone. Initial stack heatup and performance characterization occurs at ambient pressure followed by lowering and sealing of the pressure vessel and subsequent pressurization. Pressure equalization between the anode and cathode sides of the cells and the stack surroundings is ensured by combining all of the process gases downstream of the stack. Steady pressure is maintained by means of a backpressure regulator and a digital pressure controller. A full description of the pressurized test apparatus is provided in this report. Results of initial testing showed the expected increase in open-cell voltage associated with elevated pressure. However, stack performance in terms of area-specific resistance was enhanced at elevated pressure due to better gas diffusion through the porous electrodes of the cells. Some issues such as cracked cells and seals were encountered during testing. Full resolution of these issues will require additional testing to identify the optimum test configurations and protocols.

J.E. O'Brien; X. Zhang; G.K. Housley; K. DeWall; L. Moore-McAteer

2012-09-01T23:59:59.000Z

142

Microdischarge-assisted ignition of dielectric-barrier high-pressure glow discharges  

E-Print Network [OSTI]

in the ignition of high-pressure arc lamps8 and volume dc discharges.6 Here, we employ a hybrid discharge source of uniform, nonequilibrium glow plasmas for a variety of applications at pressures of 100

Raja, Laxminarayan L.

143

Plasma etching of cavities into diamond anvils for experiments at high pressures and high temperatures  

SciTech Connect (OSTI)

We describe a method for precisely etching small cavities into the culets of diamond anvils for the purpose of providing thermal insulation for samples in experiments at high pressures and high temperatures. The cavities were fabricated using highly directional oxygen plasma to reactively etch into the diamond surface. The lateral extent of the etch was precisely controlled to micron accuracy by etching the diamond through a lithographically fabricated tungsten mask. The performance of the etched cavities in high-temperature experiments in which the samples were either laser heated or electrically heated is discussed.

Weir, S.T.; Cynn, H.; Falabella, S.; Evans, W.J.; Aracne-Ruddle, C.; Farber, D.; Vohra, Y.K. (LLNL); (UAB)

2012-10-23T23:59:59.000Z

144

Instrumentation development for neutron scattering at high pressure.  

E-Print Network [OSTI]

??Neutron scattering at extremes of pressure is a powerful tool for studying the response of structural and magnetic properties of materials on microscopic level to… (more)

Fang, Junwei

2012-01-01T23:59:59.000Z

145

The Use of High Pressures for Steam Turbine Installations  

Science Journals Connector (OSTI)

... Thus, from the point of view of the manufacturer whose aim is to produce a turbine of the highest ... of the highest efficiency, that is, one which will convert into useful work the highest possible proportion of ...

STANLEY S. COOK

1926-09-25T23:59:59.000Z

146

High pressure water pyrolysis of coal to evaluate the role of pressure on hydrocarbon generation and source rock maturation at high maturities under geological conditions  

Science Journals Connector (OSTI)

Abstract This study investigates the effect of water pressure on hydrocarbon generation and source rock maturation at high maturities for a perhydrous Tertiary Arctic coal, Svalbard. Using a 25 ml Hastalloy vessel, the coal was pyrolysed under low water pressure (230–300 bar) and high water pressure (500, 700 and 900 bar) conditions between 380 °C and 420 °C for 24 h. At 380 °C and 420 °C, gas yields were not affected by pressure up to 700 bar, but were reduced slightly at 900 bar. At 380 °C, the expelled oil yield was highest at 230 bar, but reduced significantly at 900 bar. At 420 °C cracking of expelled oil to gas was retarded at 700 and 900 bar. As well as direct cracking of the coal, the main source of gas generation at high pressure at both 380 °C and 420 °C is from bitumen trapped in the coal, indicating that this is a key mechanism in high pressure geological basins. Vitrinite reflectance (VR) was reduced by 0.16 %Ro at 380 °C and by 0.27 %Ro at 420 °C at 900 bar compared to the low pressure runs, indicating that source rock maturation will be more retarded at higher maturities in high pressure geological basins.

Clement N. Uguna; Andrew D. Carr; Colin E. Snape; Will Meredith

2015-01-01T23:59:59.000Z

147

Flash High-Pressure Condensate to Regenerate Low-Pressure Steam  

SciTech Connect (OSTI)

This revised ITP tip sheet on regenerating low-pressure steam provides how-to advice for improving industrial steam systems using low-cost, proven practices and technologies.

Not Available

2006-01-01T23:59:59.000Z

148

A Flow-Through High-Pressure Electrical Conductance Cell for Determining of Ion Association of Aqueous Electrolyte Solutions at High Temperature and Pressure  

SciTech Connect (OSTI)

A flow-through high-pressure electrical conductance cell was designed and constructed to measure limiting molar conductances and ion association constants of dilute aqueous solutions with high precision at high temperatures and pressures. The basic concept of the cell employs the principle developed at the University of Delaware in 1995, but overall targets higher temperatures (to 600 C) and pressures (to 300 MPa). At present the cell has been tested by measuring aqueous NaCl and LiOH solutions (10{sup {minus}3} to 10{sup {minus}5} mol.kg{sup {minus}1}) to 405 C and 33 MPa with good results.

Bianchi, H.; Ho, P.C.; Palmer, D.A.; Wood, R.H.

1999-09-12T23:59:59.000Z

149

Structure and elasticity of serpentine at high-pressure Mainak Mookherjee a,  

E-Print Network [OSTI]

volcanoes, high electrical conductivities, magnetic and seismic anomalies. Using theoretical methods, we. Evidence of pressure- induced hydrogen bonding is absent in serpentine, as evident from reduction of O K is the bulk modulus, prime indicates pressure derivatives, and O refers to zero pressure. Our best

Stixrude, Lars

150

Mathematical modeling of high-pressure PEM water electrolysis  

Science Journals Connector (OSTI)

This paper is devoted to the modeling and numerical optimization of proton-exchange membrane (PEM) water electrolysers for operation at elevated pressures (up ... evolution reactions, the electro-osmotic drag of

S. A. Grigoriev; A. A. Kalinnikov; P. Millet…

2010-05-01T23:59:59.000Z

151

Instrumentation development for neutron scattering at high pressure   

E-Print Network [OSTI]

Neutron scattering at extremes of pressure is a powerful tool for studying the response of structural and magnetic properties of materials on microscopic level to applied stresses. However, experimental neutron studies ...

Fang, Junwei

2012-11-29T23:59:59.000Z

152

HIGH-PRESSURE SOLVENT EXTRACTION OF METHANE FROM GEOPRESSURED...  

Office of Scientific and Technical Information (OSTI)

to be about 100 based on CH4 solubility in brine at 50-125C from O'Sullivan and Smith (11), tnd low pressure CH solubility in hexadecane at 25-2002 from Cukor and Prausni...

153

DOE Hydrogen Delivery Analysis and High Pressure Tanks R&D Project Review Meeting Agenda  

Broader source: Energy.gov [DOE]

DOE Hydrogen Delivery Analysis and High Pressure Tanks R&D Project Review Meeting Agenda, held February 8-9, 2005 by Argonne National Laboratory

154

Consider Installing High-Pressure Boilers with Backpressure Turbine-Generators  

Broader source: Energy.gov [DOE]

This tip sheet outlines the benefits of high-pressure boilers with backpressure turbine-generators as part of optimized steam systems.

155

Modeling and simulation of a high pressure hydrogen storage tank with Dynamic Wall.  

E-Print Network [OSTI]

??Hydrogen storage is one of the divisions of hydrogen powered vehicles technology. To increase performances of high pressure hydrogen storage tanks, a multilayered design is… (more)

Cumalioglu, Ilgaz

2005-01-01T23:59:59.000Z

156

Modeling and simulation of a high pressure hydrogen storage tank with dynamic wall.  

E-Print Network [OSTI]

??Hydrogen storage is one of the divisions of hydrogen powered vehicles technology. To increase performances of high pressure hydrogen storage tanks, a multilayered design is… (more)

Cumalioglu, Ilgaz

2005-01-01T23:59:59.000Z

157

Device for testing closure disks at high rates of change of pressure  

DOE Patents [OSTI]

A device is described for testing the burst pressure of closure disks which provides high pressure to both sides of a disk and rapidly releases pressure from one side thereof causing a high rate of change of pressure. A hollow notched plug allows the rapid release of pressure upon rupturing. A means is also disclosed for transmitting a tensile load from a piston to a hollow notched plug and for sealing the means for transmitting load within a hole in a piston. 5 figures.

Merten, C.W. Jr.

1993-11-09T23:59:59.000Z

158

Velocity of Sound Measurements in High?Pressure, High?Temperature Steam  

Science Journals Connector (OSTI)

Experimental information concerning the acoustic velocity in steam as a function of pressure and temperature is quite limited. Yet it is of particular interest to steam turbine designers who are now planning units as large as 400 000 kw operating at 4500 lb/sq in. and 1200°F so as to increase thermal efficiencies of such units. Apparatus is now in operation for measuring the acoustic velocity up to 2000 lb/sq in. and 750°F using a variable path acoustic interferometer.Measurements are taken at 200?lb/sq in. intervals along a given isotherm using a sound frequency of 750 kc. A special experimental high?pressure boiler is used to generate the steam at the desired pressure and the stem is then increased in temperature by means of a stainless steel superheater before entering the interferometer. The interferometer also of stainless steel is enclosed by an insulated steel vessel maintained at a given constant temperature by another separate steam system. Future work is now being considered up to 6000?lb/sq in. steam pressure based upon results of present experiments.

James Woodburn

1960-01-01T23:59:59.000Z

159

High-pressure phase transition and behavior of protons in brucite Mg(OH)2: a high-pressure–temperature study using IR synchrotron radiation  

Science Journals Connector (OSTI)

?Infrared absorption spectra of brucite Mg (OH)2...were measured under high pressure and high temperature from 0.1?MPa 25?°C to 16?GPa 360?°C using infrared synchrotron radiation at BL43IR of Spring-8 and a high-...

K. Shinoda; M. Yamakata; T. Nanba; H. Kimura…

2002-07-01T23:59:59.000Z

160

An In-situ Tensile Test Apparatus for Polymers in High Pressure Hydrogen  

SciTech Connect (OSTI)

Degradation of material properties by high-pressure hydrogen is an important factor in determining the safety and reliability of materials used in high-pressure hydrogen storage and delivery. Hydrogen damage mechanisms have a time dependence that is linked to hydrogen outgassing after exposure to the hydrogen atmosphere that makes ex-situ measurements of mechanical properties problematic. Designing in-situ measurement instruments for high-pressure hydrogen is challenging due to known hydrogen incompatibility with many metals and standard high-power motor materials like Nd. Here we detail the design and operation of a solenoid based in-situ tensile tester under high-pressure hydrogen environments up to 5,000 psi. Modulus data from high-density polyethylene (HDPE) samples tested under high-pressure hydrogen are also reported as compared to baseline measurements taken in air.

Alvine, Kyle J.; Kafentzis, Tyler A.; Pitman, Stan G.; Johnson, Kenneth I.; Skorski, Daniel C.; Tucker, Joseph C.; Roosendaal, Timothy J.; Dahl, Michael E.

2014-10-10T23:59:59.000Z

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


161

An in situ tensile test apparatus for polymers in high pressure hydrogen  

SciTech Connect (OSTI)

Degradation of material properties by high-pressure hydrogen is an important factor in determining the safety and reliability of materials used in high-pressure hydrogen storage and delivery. Hydrogen damage mechanisms have a time dependence that is linked to hydrogen outgassing after exposure to the hydrogen atmosphere that makes ex situ measurements of mechanical properties problematic. Designing in situ measurement instruments for high-pressure hydrogen is challenging due to known hydrogen incompatibility with many metals and standard high-power motor materials such as Nd. Here we detail the design and operation of a solenoid based in situ tensile tester under high-pressure hydrogen environments up to 42 MPa (6000 psi). Modulus data from high-density polyethylene samples tested under high-pressure hydrogen at 35 MPa (5000 psi) are also reported as compared to baseline measurements taken in air.

Alvine, K. J., E-mail: kyle.alvine@pnnl.gov; Kafentzis, T. A.; Pitman, S. G.; Johnson, K. I.; Skorski, D.; Tucker, J. C.; Roosendaal, T. J.; Dahl, M. E. [Energy and Environment Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354 (United States)

2014-10-15T23:59:59.000Z

162

Development of Designer Diamond Technology for High Pressure High Temperature Experiments in Support of Stockpile Stewardship Program  

SciTech Connect (OSTI)

The role of nitrogen in the fabrication of designer diamond was systematically investigated by adding controlled amount of nitrogen in hydrogen/methane/oxygen plasma. This has led to a successful recipe for reproducible fabrication of designer diamond anvils for high-pressure high-temperature research in support of stockpile stewardship program. In the three-year support period, several designer diamonds fabricated with this new growth chemistry were utilized in high-pressure experiments at UAB and Lawrence Livermore National Laboratory. The designer diamond anvils were utilized in high-pressure studies on heavy rare earth metals, high pressure melting studies on metals, and electrical resistance measurements on iron-based layered superconductors under high pressures. The growth chemistry developed under NNSA support can be adapted for commercial production of designer diamonds.

Vohra, Yogesh, K.

2009-10-28T23:59:59.000Z

163

Constant pressure high throughput membrane permeation testing system  

DOE Patents [OSTI]

The disclosure relates to a membrane testing system for individual evaluation of a plurality of planar membranes subjected to a feed gas on one side and a sweep gas on a second side. The membrane testing system provides a pressurized flow of a feed and sweep gas to each membrane testing cell in a plurality of membrane testing cells while a stream of retentate gas from each membrane testing cell is ported by a retentate multiport valve for sampling or venting, and a stream of permeate gas from each membrane testing cell is ported by a permeate multiport valve for sampling or venting. Back pressure regulators and mass flow controllers act to maintain substantially equivalent gas pressures and flow rates on each side of the planar membrane throughout a sampling cycle. A digital controller may be utilized to position the retentate and permeate multiport valves cyclically, allowing for gas sampling of different membrane cells over an extended period of time.

Albenze, Erik J.; Hopkinson, David P.; Luebke, David R.

2014-09-02T23:59:59.000Z

164

Ionization and equation of state of dense xenon at high pressures and high temperatures  

Science Journals Connector (OSTI)

The ionization degree and equation of state of dense xenon plasma were calculated by using self-consistent fluid variational theory for temperature of 4–30kK and density of 0.01–8.5g?cm3. The dense fluid xenon will be ionized at high pressures and temperatures. The ionization energy of xenon will be lowered due to the interactions among all particles of Xe, Xe+, Xe2+, and e. The ionization degree is obtained from nonideal ionization equilibrium, taking into account the correlative contributions to the chemical potential which is determined self-consistently by the free energy function. The composition of xenon has been calculated with given densities and temperatures in the region of partial ionization. The calculated results show a pressure softening regime at the onset of ionization. Comparison is performed with available shock-wave experiments and other theoretical calculations.

Q. F. Chen, L. C. Cai, Y. J. Gu, and Y. Gu

2009-01-22T23:59:59.000Z

165

High-temperature fiber optic cubic-zirconia pressure sensor - article no. 124402  

SciTech Connect (OSTI)

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{sup o}C. Additional experimental results show that cubic zirconia could be used for pressure sensing at temperatures over 1000{sup o}C. This study demonstrates the feasibility of using a novel cubic-zirconia sensor for pressure measurement at high temperatures.

Peng, W.; Pickrell, G.R.; Wang, A.B. [Virginia Polytechnic Institute & State University, Blacksburg, VA (United States)

2005-12-15T23:59:59.000Z

166

Development of High-Pressure Dry Feed Pump for Gasification Systems  

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

Pressure Dry Feed Pressure Dry Feed Pump for Gasification Systems Background Even though coal-based power generation via Integrated Gasification Combined Cycle (IGCC) is more efficient, cleaner, and uses less water than conventional pulverized coal burning systems, widespread IGCC deployment has not occurred because of its relatively high cost. The Pratt & Whitney Rocketdyne (PWR) high-pressure dry feed pump addresses IGCC cost disparity by enabling lower cost and more reliable coal feed

167

Carbon Nanotubes as High-Pressure Cylinders and Nanoextruders  

Science Journals Connector (OSTI)

...nanotubes and demonstrated that even hard materials such as iron carbide or cobalt can be extruded under the pressures prevailing...dissolving 3 weight percent of a metallocene (ferrocene or cobalt acetylacetonate) in ethanol (for Fe) or toluene (for Co); the solution...

L. Sun; F. Banhart; A. V. Krasheninnikov; J. A. Rodríguez-Manzo; M. Terrones; P. M. Ajayan

2006-05-26T23:59:59.000Z

168

High-Current Gas Discharge at Low Pressures  

Science Journals Connector (OSTI)

... Probe measurements in a mercury-vapour arc tube (diameter 54 mm.) at pressures less than 10-3 mm. show that ... than 10-3 mm. show that at currents greater than 50 amp. the radial_electric field Es is negligible compared to the term w1H except close to the tube walls ...

P. C. THONEMANN; W. T. COWHIG

1950-11-25T23:59:59.000Z

169

Testing the physics of heat conduction using high pressure: crystals, glasses, and interfaces  

E-Print Network [OSTI]

, simplest case of thermal conductivity where resistive scattering dominates C() v() l() d C() = heatTesting the physics of heat conduction using high pressure: crystals, glasses, and interfaces David supported by CDAC and AFOSR #12;The story... · Use high pressure (gem anvil cells) to modify vibrational

Braun, Paul

170

Analysis and simplification of a mathematical model for high-pressure food processes  

Science Journals Connector (OSTI)

Nowadays, consumers look for minimally processed, additive-free food products that maintain their organoleptic properties. This has led to the development of new technologies for food processing. One emerging technology is high hydrostatic pressure, ... Keywords: Boundary layer solution, Food technology, Heat transfer, High pressure, Modelling, Separation of variables solution

N. A. S. Smith, S. L. Mitchell, A. M. Ramos

2014-01-01T23:59:59.000Z

171

Ettringite Strengthening at High Pressures Induced by the Densification of the Hydrogen Bond Network  

Science Journals Connector (OSTI)

Ettringite Strengthening at High Pressures Induced by the Densification of the Hydrogen Bond Network ... Ettringite is a rare mineral with high-water content, more than half of its weight, and a relevant secondary product in Portland cement. ... Using density functional theory, we simulate the crystal structure and properties of ettringite under pressure. ...

H. Manzano; A. Ayuela; A. Telesca; P. J. M. Monteiro; J. S. Dolado

2012-07-06T23:59:59.000Z

172

A high-pressure and high-temperature gas-loading system for the study of conventional to real industrial sized samples in catalysed gas/solid and liquid/solid reactions  

Science Journals Connector (OSTI)

A high-pressure-high-temperature gas-loading system has been developed for combined in situ high-energy X-ray diffraction and mass spectrometry investigations during catalysed gas/solid or liquid/solid reactions. The benefits of such a system are the combination of different gases, the flexibility of the cell design, the rotation of the cell, and the temperature, pressure and gas-flow ranges accessible. This opens up new opportunities for studying catalysts or compounds not just from a fundamental point of view but also for industrial applications, in both cases in operando conditions.

Andrieux, J.

2014-01-18T23:59:59.000Z

173

Generalized enthalpy model of a high-pressure shift freezing process  

Science Journals Connector (OSTI)

...non-homogeneous temperature distribution induces a non-homogeneous...computational model for temperature and sterility distributions in a pilot-scale...high-pressure high-temperature process. A.I...and Da-Wen. Sun 2009 Simulation...

2012-01-01T23:59:59.000Z

174

Electron Matter Wave Interferences at High Vacuum Pressures  

E-Print Network [OSTI]

The ability to trap and guide coherent electrons is gaining importance in fundamental as well as in applied physics. In this regard novel quantum devices are currently developed that may operate under low vacuum conditions. Here we study the loss of electron coherence with increasing background gas pressure. Thereby optionally helium, hydrogen or nitrogen is introduced in a biprism interferometer where the interference contrast is a measure for the coherence of the electrons. The results indicate a constant contrast that is not decreasing in the examined pressure range between $10^{-9}$ mbar and $10^{-4}$ mbar. Therefore no decoherence was observed even under poor vacuum conditions. Due to scattering of the electron beam with background H$_2$-molecules a signal loss of 94 % was determined. The results may lower the vacuum requirements for novel quantum devices with free coherent electrons.

Schütz, Georg; Pooch, Andreas; Stibor, Alexander

2015-01-01T23:59:59.000Z

175

Ortho-para conversion of hydrogen at high pressures  

Science Journals Connector (OSTI)

Ortho-para conversion rates in solid H2 measured as a function of pressure up to 58 GPa are examined theoretically. Analyses of the data provide information on the relative role of diffusion versus intrinsic dependences of the conversion rate on ortho concentration. A theory of the conversion has been developed using a closed-form representation of the conversion promoting nuclear magnetic interaction Hss expanded in spherical harmonics. The mechanisms considered include double conversion, excitations in the J=1 and J=2 manifolds as conversion energy sinks, and a possibility of intermediate states from which the conversion energy is dissipated via the strong electrical quadrupole-quadrupole (EQQ) interaction. Conversion rates were evaluated for a total of 12 new channels; the two other channels considered previously for moderate pressures have been reconsidered to account for factors that influence phonon-assisted energy dissipation, the most important being the compression-related decrease of the conversion energy (gap closing). Contributions from the standard one-phonon channels with single and double conversion yield fairly good agreement with low-pressure data. The proposed new channel identified as responsible for the observed conversion acceleration is the one in which the conversion Hamiltonian Hss only initiates conversion driving the system to a temporarily nonequilibrium state from which the conversion energy is dissipated via EQQ coupling into excitations within the J=1 manifold. Our mechanism predicts a strong and abrupt conversion slowdown at still higher compressions. The abrupt decrease in rate observed at a given pressure at longer times (decreasing ortho fractions) can be explained as due to the inability of slow diffusion to restore the random distribution of ortho species and due to the intrinsic inefficiency of the new channel at low c.

Mikhail A. Strzhemechny; Russell J. Hemley; Ho-kwang Mao; Alexander F. Goncharov; Jon H. Eggert

2002-07-10T23:59:59.000Z

176

Heat transfer and pressure drop data for high heat flux densities to water at high subcritical pressures  

E-Print Network [OSTI]

Local surface ooeffioients of heat t-ansfer, overall pressure drop data and mean friction factor are presented for heat flamms up to 3.52106 BtuAr ft2 for water flowing in a nickel tabe isder the following conditions: mass ...

Rohsenow, Warren M.

1951-01-01T23:59:59.000Z

177

BILIWG Meeting: High Pressure Steam Reforming of Bio-Derived Liquids (Presentation)  

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

High Pressure Steam Reforming of High Pressure Steam Reforming of Bio-Derived Liquids S. Ahmed, S. Lee, D. Papadias, and R. Kumar November 6, 2007 Laurel, MD Research sponsored by the Hydrogen, Fuel Cells, and Infrastructure Technologies Program of DOE's Office of Energy Efficiency and Renewable Energy Rationale and objective Rationale „ Steam reforming of liquid fuels at high pressures can reduce hydrogen compression costs - Much less energy is needed to pressurize liquids (fuel and water) than compressing gases (reformate or H 2 ) „ High pressure reforming is advantageous for subsequent separations and hydrogen purification Objective „ Develop a reformer design that takes advantage of the savings in compression cost in the steam reforming bio-derived liquid fuels - Metric:

178

Development of a High-Pressure/High-Temperature Downhole Turbine Generator  

SciTech Connect (OSTI)

The objective of this project as originally outlined has been to achieve a viable downhole direct current (DC) power source for extreme high pressure, high temperature (HPHT) environments of >25,000 psi and >250 C. The Phase I investigation posed and answered specific questions about the power requirements, mode of delivery and form factor the industry would like to see for downhole turbine generator tool for the HPHT environment, and noted specific components, materials and design features of that commercial system that will require upgrading to meet the HPHT project goals. During the course of Phase I investigation the scope of the project was HPHT downhole DC power. Phase I also investigated the viability of modifying a commercial expanded, without additional cost expected to the project, to include the addition of HT batteries to the power supply platform.

Timothy F. Price

2007-02-01T23:59:59.000Z

179

High Pressure X-ray Diffraction Study of Potassium Azide  

SciTech Connect (OSTI)

Crystal structure and compressibility of potassium azide was investigated by in-situ synchrotron powder X-ray diffraction in a diamond anvil cell at room temperature up to 37.7 GPa. In the body-centered tetragonal (bct) phase, an anisotropic compressibility was observed with greater compressibility in the direction perpendicular to the plane containing N{sub 3}{sup -} ions than directions within that plane. The bulk modulus of the bct phase was determined to be 18.6(7) GPa. A pressure-induced phase transition may occur at 15.5 GPa.

C Ji; F Zhang; D Hong; H Zhu; J Wu; M Chyu; V Levitas; Y Ma

2011-12-31T23:59:59.000Z

180

Prediction and Correlation of High-Pressure Gas Solubility in Polymers with Simplified PC-SAFT  

Science Journals Connector (OSTI)

Prediction and Correlation of High-Pressure Gas Solubility in Polymers with Simplified PC-SAFT ... Using simplified PC-SAFT we have modeled gas solubilities at high temperatures and pressures for the gases methane and carbon dioxide in each of the three polymers high-density polyethylene (HDPE), nylon polyamide-11 (PA-11), and poly(vinylidene fluoride) (PVDF). ... Equations of Simplified PC-SAFT ...

Nicolas von Solms; Michael L. Michelsen; Georgios M. Kontogeorgis

2005-03-26T23:59:59.000Z

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


181

Phase Transitions in Solids Stimulated by Simultaneous Exposure to High Pressure and Relativistic Heavy Ions  

Science Journals Connector (OSTI)

In many solids, heavy ions of high kinetic energy (MeV-GeV) produce long cylindrical damage trails with diameters of order 10 nm. Up to now, no information was available how solids cope with the simultaneous exposure to these energetic projectiles and to high pressure. We report the first experiments where relativistic uranium and gold ions from the SIS heavy-ion synchrotron at GSI were injected through several mm of diamond into solid samples pressurized up to 14 GPa in a diamond anvil cell. In synthetic graphite and natural zircon, the combination of pressure and ion beams triggered drastic structural changes not caused by the applied pressure or the ions alone. The modifications comprise long-range amorphization of graphite rather than individual track formation, and in the case of zircon the decomposition into nanocrystals and nucleation of the high-pressure phase reidite.

Ulrich A. Glasmacher; Maik Lang; Hans Keppler; Falko Langenhorst; Reinhard Neumann; Dieter Schardt; Christina Trautmann; Günther A. Wagner

2006-05-17T23:59:59.000Z

182

Wear damage resulting from sliding impact kinematics in pressurized high temperature water: energetical and  

E-Print Network [OSTI]

1 Wear damage resulting from sliding impact kinematics in pressurized high temperature water and Cecile Langlade2,3 1 FRAMATOME-ANP Technical Center, Avenue B. Marcet, Porte Magenta, 71200 Le Creusot.bec@ec-lyon.fr Abstract Specific wear of Rod Cluster Control Assemblies (RCCA) in Pressurized Water nuclear Reactors (PWR

Paris-Sud XI, Université de

183

Development test report for the high pressure water jet system nozzles  

SciTech Connect (OSTI)

The high pressure water jet nozzle tests were conducted to identify optimum water pressure, water flow rate, nozzle orifice size and fixture configuration needed to effectively decontaminate empty fuel storage canisters in KE-Basin. This report gives the tests results and recommendations from the these tests.

Takasumi, D.S.

1995-09-28T23:59:59.000Z

184

Influence of dissociative recombination on the LTE of argon high-frequency plasmas at atmospheric pressure  

E-Print Network [OSTI]

) model that we developed for an argon microwave (2.45 GHz) plasma at atmospheric pressure. This model-1- Influence of dissociative recombination on the LTE of argon high-frequency plasmas at atmospheric pressure A. Sáinz1 , J. Margot2 , M. C. García1 , M. D. Calzada1 1 Grupo de Espectroscopía de

Boyer, Edmond

185

Kinetic Analysis of CO2 Gasification of Petroleum Coke at High Pressures  

Science Journals Connector (OSTI)

Two petcoke samples were gasified by CO2 at total pressures of 10 and 15 atm in a high-pressure flat-flame burner reactor at conditions where the bulk phase consisted of either 40 or 90 mol % CO2 with gas temperatures up to 1909 K. Particle diameters of ... ...

Maryam Malekshahian; Josephine M. Hill

2011-08-10T23:59:59.000Z

186

Hydrogen incorporation in stishovite at high pressure and symmetric hydrogen bonding in N-AlOOH  

E-Print Network [OSTI]

Hydrogen incorporation in stishovite at high pressure and symmetric hydrogen bonding in N significant amounts of hydrogen in stishovite under lower-mantle conditions. The enthalpy of solution pressure and temperature. We predict asymmetric hydrogen bonding in the stishovite^N-AlOOH solid solution

Stixrude, Lars

187

Extremely high-pressure generation and compression with laser implosion plasmas  

SciTech Connect (OSTI)

We have tested a scheme for using laser implosion plasmas to generate pressures in the gigabar (100 TPa) regime. Cone-in-shell targets employed in fast ignition of inertial confinement fusion were irradiated to create a high-pressure source for compression of materials. The imploded plasmas pushed a foil embedded on the tip of a cone. The pressure was estimated from the shock velocity into the material; the shock velocity was obtained from an optical measurement. The measured shock velocity of the foil was above 100 km/s, corresponding to a pressure greater than 1 Gbar.

Shigemori, K.; Hironaka, Y.; Nagatomo, H.; Fujioka, S.; Azechi, H. [Institute of Laser Engineering, Osaka University, 2-6 Yamada-Oka, Suita, Osaka 565-0871 (Japan)] [Institute of Laser Engineering, Osaka University, 2-6 Yamada-Oka, Suita, Osaka 565-0871 (Japan); Sunahara, A. [Institute for Laser Technology, 2-6 Yamada-Oka, Suita, Osaka 565-0871 (Japan)] [Institute for Laser Technology, 2-6 Yamada-Oka, Suita, Osaka 565-0871 (Japan); Kadono, T. [University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 (Japan)] [University of Occupational and Environmental Health, 1-1 Iseigaoka, Yahata-nishi-ku, Kitakyushu, Fukuoka 807-8555 (Japan); Shimizu, K. [Center for Quantum Science and Technology under Extreme Conditions, Osaka University, 1-3 Machikaneyama-Cho, Toyonaka 560-0831 (Japan)] [Center for Quantum Science and Technology under Extreme Conditions, Osaka University, 1-3 Machikaneyama-Cho, Toyonaka 560-0831 (Japan)

2013-05-06T23:59:59.000Z

188

High rate deposition of microcrystalline silicon films by high-pressure radio frequency plasma enhanced chemical vapor deposition (PECVD)  

Science Journals Connector (OSTI)

Hydrogenated microcrystalline silicon (?c-Si:H) thin films were prepared by high-pressure radio-frequency (13.56 MHz) plasma enhanced chemical vapor deposition (rf-PECVD) with a screened plasma. The deposition ra...

BingQing Zhou; MeiFang Zhu; FengZhen Liu…

2008-04-01T23:59:59.000Z

189

High-pressure cell for neutron reflectometry of supercritical and subcritical fluids at solid interfaces  

SciTech Connect (OSTI)

A new high-pressure cell design for use in neutron reflectometry (NR) for pressures up to 50 MPa and a temperature range of 300 473 K is described. The cell design guides the neutron beam through the working crystal without passing through additional windows or the bulk fluid, which provides for a high neutron transmission, low scattering background, and low beam distortion. The o-ring seal is suitable for a wide range of subcritical and supercritical fluids and ensures high chemical and pressure stability. Wafers with a diameter of 5.08 cm (2 in.) and 5 mm or 10 mm thickness can be used with the cells, depending on the required pressure and momentum transfer range. The fluid volume in the sample cell is very small at about 0.1 ml, which minimizes scattering background and stored energy. The cell design and pressure setup for measurements with supercritical fluids are described. NR data are shown for silicon/silicon oxide and quartz wafers measured against air and subsequently within the high-pressure cell to demonstrate the neutron characteristics of the high-pressure cell. Neutron reflectivity data for supercritical CO2 in contact with quartz and Si/SiO2 wafers are also shown.

Carmichael, Justin R [ORNL; Rother, Gernot [ORNL; Browning, Jim [ORNL; Ankner, John Francis [ORNL; Banuelos, Jose Leo [ORNL; Anovitz, Lawrence {Larry} M [ORNL; Wesolowski, David J [ORNL; Cole, David [Ohio State University

2012-01-01T23:59:59.000Z

190

A device for debridement using high pressure water jets  

E-Print Network [OSTI]

Removing devitalized tissue from chronic wounds through debridement is critical to promote wound healing. In this thesis, technology using high-speed water jets is explored toward applications for debridement. After ...

Brown, Ashley (Ashley A.)

2014-01-01T23:59:59.000Z

191

Pantex High Pressure Fire Loop Project Completed On Time, Under Budget |  

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

High Pressure Fire Loop Project Completed On Time, Under Budget | High Pressure Fire Loop Project Completed On Time, Under Budget | National Nuclear Security Administration Our Mission Managing the Stockpile Preventing Proliferation Powering the Nuclear Navy Emergency Response Recapitalizing Our Infrastructure Continuing Management Reform Countering Nuclear Terrorism About Us Our Programs Our History Who We Are Our Leadership Our Locations Budget Our Operations Media Room Congressional Testimony Fact Sheets Newsletters Press Releases Speeches Events Social Media Video Gallery Photo Gallery NNSA Archive Federal Employment Apply for Our Jobs Our Jobs Working at NNSA Blog Home > Media Room > Press Releases > Pantex High Pressure Fire Loop Project Completed ... Press Release Pantex High Pressure Fire Loop Project Completed On Time, Under Budget

192

DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project Review Meeting  

Broader source: Energy.gov [DOE]

On February 8-9, 2005, the Department of Energy held the DOE Hydrogen Delivery High-Pressure Tanks and Analysis Project Review Meeting at Argonne National Laboratory. The purpose of the meeting was...

193

Microplasma Discharges in High Pressure Gases Scaling Towards the Sub-micron Regime  

E-Print Network [OSTI]

Atmospheric pressure microplasmas are uniquely characterized by their very high energy densities and also by their small discharge sizes. These properties allow for unique applications in plasma processing technologies. We have investigated...

Chitre, Aditya Rajeev

2012-02-14T23:59:59.000Z

194

Vibrational Spectroscopy at High Pressure in CF4: Implications to the Phase Diagram  

SciTech Connect (OSTI)

The molecular analogue of methane, CF{sub 4} is the most fundamental saturated perfluorocarbon, exhibiting complex optical behavior that is highly unusual for such a simple molecular system. We present Raman measurements in solid CF{sub 4} over a wide range in pressure from 1.6 to over 30 GPa at room temperature. The Raman spectra exhibit polarization-dependent intensity variations and history-dependent absence or presence of high pressure modes. Our results compellingly demonstrate that previously identified phase transitions in CF{sub 4} based on Raman signatures need to be reconsidered. Though our data suggest possible new high-pressure transitions, we do not identify new phases because of spectral complexity. Finally, we used the measured longitudinal and transverse optical mode splitting to estimate the dipole moment derivative at high pressures and find it close to that of gaseous CF{sub 4}.

Lorenzana, H E; Magnus, J L; Evans, W J; Hemmi, N

2000-08-15T23:59:59.000Z

195

Refractory products and ramming bodies for high pressure burners of steam boilers  

Science Journals Connector (OSTI)

Silicon carbide rammed bodies are suitable for lining the combustion zones of high-pressure cyclone burners of steam boilers. The life of the silicon carbide body depends on the heat resistance of the supporti...

N. I. Voronin; N. I. Krasotkina; A. I. kulik; T. S. Karmanova; G. E. Levin…

196

Evaluation of energy efficiency in cutting aerospace materials with high-pressure cooling lubricant supply  

Science Journals Connector (OSTI)

In the field of machining difficult-to-cut materials like titanium or nickel-based alloys, the use of high-pressure cooling lubricant supply (HPCLS) offers ... , tool wear can be decreased which allows higher app...

Fritz Klocke; Dieter Lung; Tolga Cayli…

2014-06-01T23:59:59.000Z

197

Methane-to-hydrogen conversion in a reversible flow filtration combustion reactor at a high pressure  

Science Journals Connector (OSTI)

The noncatalytic process of partial oxidation of methane to syngas in a reversible flow filtration combustion reactor at high pressures has been considered. ... conversion process — the maximum temperature in the...

Yu. M. Dmitrenko; P. A. Klyovan

2013-09-01T23:59:59.000Z

198

Magnetic and structural phase transitions in erbium at low temperatures and high pressures  

SciTech Connect (OSTI)

Electrical resistance and crystal structure measurements have been carried out on polycrystalline erbium (Er) at temperatures down to 10 K and pressures up to 20 GPa. An abrupt change in the slope of the resistance is observed with decreasing temperature below 84 K, which is associated with the c-axis modulated (CAM) antiferromagnetic (AFM) ordering of the Er moments. With increasing pressure the temperature of the resistance slope change and the corresponding AFM ordering temperature decrease until vanishing above 10.6 GPa. The disappearance of the slope change in the resistance occurs at similar pressures where the hcp structural phase of Er is transformed to a nine-layer {alpha}-Sm structural phase, as confirmed by our high-pressure synchrotron x-ray diffraction studies. These results suggest that the disappearance in the AFM ordering of Er moments is strongly correlated to the structural phase transition at high pressures and low temperatures.

Thomas, Sarah A.; Tsoi, Georgiy M.; Wenger, Lowell E.; Vohra, Yogesh K. (UAB)

2012-02-07T23:59:59.000Z

199

Thermodynamic properties of carbonates at high pressures from vibrational modelling  

Science Journals Connector (OSTI)

...Mineral. , 84 , 856-860. Frech, R., Wang, E.C., Bates, J.B. (1980...Physica B , 262 , 67-73. Guyot, F., Wang, P., Gillet, P., Ricard, Y...high-temperature volumes of olivines by synchroton X-ray diffraction. Comparison with...

Jan MATAS; Philippe GILLET; Yanick RICARD; Isabelle MARTINEZ

200

High Temperature and Pressure reactive flows through porous media.  

E-Print Network [OSTI]

of Ceramic Matrix Composite (CMC), used as high temperature material for combustion chamber or stagnation and chemical composition (Gas Chromatograph, Mass Spectrometer, Infra-Red spectrometer) in stationary and transient conditions. The tests on metallic and composite samples have been conducted with N2, CH4, H2+CH4

Boyer, Edmond

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


201

The mechanism of coking pressure generation II: Effect of high volatile matter coking coal, semi-anthracite and coke breeze on coking pressure and contraction  

Science Journals Connector (OSTI)

One of the most important aspects of the cokemaking process is to control and limit the coking pressure since excessive coking pressure can lead to operational problems and oven wall damage. Following on from a previous paper on plastic layer permeability we have studied the effect of contraction of semi-coke on coking pressure and the effect of organic additives on contraction. A link between contraction (or simulated contraction) outside the plastic layer and coking pressure was demonstrated. The interaction between this contraction, local bulk density around the plastic layer and the dependence of the permeability of the plastic layer on bulk density was discussed as possible mechanisms for the generation of coking pressure. The effect of blending either a high volatile matter coal or one of two semi-anthracites with low volatile matter, high coking pressure coals on the coking pressure of the binary blends has been explained using this mechanism.

Merrick Mahoney; Seiji Nomura; Koichi Fukuda; Kenji Kato; Anthony Le Bas; David R. Jenkins; Sid McGuire

2010-01-01T23:59:59.000Z

202

High-pressure studies of rare earth material could lead to lighter, cheaper  

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

22013_earth 22013_earth 12/20/2013 A Lawrence Livermore researcher prepares a sample at Oak Ridge National Laboratory's Spallation Neutrons and Pressure Diffractometer (SNAP). High-pressure studies of rare earth material could lead to lighter, cheaper magnets Anne M Stark, LLNL, (925) 422-9799, stark8@llnl.gov Sometimes you have to apply a little pressure to get magnetic materials to reveal their secrets. By placing a permanent magnet under high pressures, Lawrence Livermore researchers are exploring how atomic structure enhances magnetic strength and resistance to demagnetization. This fundamental research into magnetic behavior has important implications for engineering stronger, cheaper magnets. Permanent magnets based on rare earth elements are in high demand for

203

High Pressure Phase Transformations in Heavy Rare Earth Metals and Connections to Actinide Crystal Structures  

SciTech Connect (OSTI)

High-pressure studies have been performed on heavy rare earth metals Terbium (Tb) to 155 GPa and Holmium (Ho) to 134 GPa in a diamond anvil cell at room temperature. The following crystal structure sequence was observed in both metals hcp {yields} Sm-type {yields} dhcp {yields} distorted fcc (hR-24) {yields} monoclinic (C2/m) with increasing pressure. The last transformation to a low symmetry monoclinic phase is accompanied by a volume collapse of 5 % for Tb at 51 GPa and a volume collapse of 3 % for Ho at 103 GPa. This volume collapse under high pressure is reminiscent of f-shell delocalization in light rare earth metal Cerium (Ce), Praseodymium (Pr), and heavy actinide metals Americium (Am) and Curium (Cm). The orthorhombic Pnma phase that has been reported in Am and Cm after f-shell delocalization is not observed in heavy rare earth metals under high pressures. (authors)

Vohra, Yogesh K.; Sangala, Bagvanth Reddy; Stemshorn, Andrew K. [Physics, University of Alabama at Birmingham (UAB), 310 Campbell Hall, 1300 University Boulevard, Birmingham, AL, 35294-1170 (United States); Hope, Kevin M. [Biology, Chemistry, and Mathematics, University of Montevallo, Harman Hall, Station 6480, Montevallo, AL, 35115 (United States)

2008-07-01T23:59:59.000Z

204

LNG Vehicle High-Pressure Fuel System and ''Cold Energy'' Utilization  

SciTech Connect (OSTI)

A high-pressure fuel system for LNG vehicles with direct-injection natural gas engines has been developed and demonstrated on a heavy-duty truck. A new concept for utilizing the ''cold energy'' associated with LNG vehicles to generate mechanical power to drive auxiliary equipment (such as high-pressure fuel pumps) has also been developed and demonstrated in the laboratory. The high-pressure LNG fuel system development included the design and testing of a new type of cryogenic pump utilizes multiple chambers and other features to condense moderate quantities of sucked vapor and discharge supercritical LNG at 3,000 to 4,000 psi. The pump was demonstrated on a Class 8 truck with a Westport high-pressure direct-injection Cummins ISX engine. A concept that utilizes LNG's ''cold energy'' to drive a high-pressure fuel pump without engine attachments or power consumption was developed. Ethylene is boiled and superheated by the engine coolant, and it is cooled and condensed by rejecting h eat to the LNG. Power is extracted in a full-admission blowdown process, and part of this power is applied to pump the ethylene liquid to the boiler pressure. Tests demonstrated a net power output of 1.1. hp at 1.9 Lbm/min of LNG flow, which is adequate to isentropically pump the LNG to approximately 3,400 psi..

powers,Charles A.; Derbidge, T. Craig

2001-03-27T23:59:59.000Z

205

Behavior of a hollow core photonic crystal fiber under high radial pressure for downhole application  

SciTech Connect (OSTI)

Pressure fiber sensors play an important role in downhole high pressure measurements to withstand long term operation. The purpose of this paper is to present an application of hollow core photonic crystal fiber (HC-PCF) as a high pressure sensor head for downhole application based on dispersion variation. We used a high pressure stainless steel unit to exert pressure on the sensor. The experimental results show that different wavelengths based on sagnac loop interferometer have additive sensitivities from 5?×?10{sup ?5}?nm/psi at 1480?nm to 1.3?×?10{sup ?3}?nm/psi at 1680?nm. We developed a simulation to understand the reason for difference in sensitivity of wavelengths and also the relationship between deformation of HC-PCF and dispersion variation under pressure. For this purpose, by using the finite element method, we investigated the effect of structural variation of HC-PCF on spectral transformation of two linear polarizations under 1000?psi pressure. The simulation and experimental results show exponential decay behavior of dispersion variation from ?3.4?×?10{sup ?6} 1/psi to ?1.3?×?10{sup ?6} 1/psi and from ?5?×?10{sup ?6} 1/psi to ?1.8?×?10{sup ?6} 1/psi, respectively, which were in a good accordance with each other.

Sadeghi, J., E-mail: j-sadeghi@sbu.ac.ir; Chenari, Z.; Ziaee, F. [Laser and Plasma Research Institute, Shahid Beheshti University, 1983963113 Tehran (Iran, Islamic Republic of); Latifi, H., E-mail: latifi@sbu.ac.ir [Laser and Plasma Research Institute, Shahid Beheshti University, 1983963113 Tehran (Iran, Islamic Republic of); Department of Physics, Shahid Beheshti University, Evin, 1983963113 Tehran (Iran, Islamic Republic of); Santos, J. L., E-mail: josantos@fc.up.pt [INESC Porto—Instituto de Engenharia de Sistemas e Computadores do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal); Departamento de Física, da Faculdade de Ciências, da Universidade do Porto, Rua do Campo Alegre, 687, 4169-007 Porto (Portugal)

2014-02-17T23:59:59.000Z

206

Atmospheric pressure plasma chemical vapor deposition system for high-rate deposition of functional materials  

Science Journals Connector (OSTI)

The atmospheric pressure plasmachemical vapor deposition(CVD) system has been developed to fabricate functional thin films at very high deposition rate. The atmospheric pressure plasma in which high-density radicals are created has been effectively used to depositthin films. Combination of the newly designed rotary electrode and the 150 MHz very high frequency power supply makes it possible not only to generate the high-density atmospheric pressure plasma but also to avoid ion bombardment against the film. By virtue of these noble characteristics of the system high quality films can be fabricated at an unprecedented high deposition rate. In order to demonstrate the effectiveness of the atmospheric pressure plasmaCVD system hydrogenated amorphous silicon (a- Si:H ) films were prepared in gas mixtures containing He H 2 and SiH 4 . The results showed that homogeneous a- Si:H films grew when substrates were heated at 200?°C. Extremely high deposition rate which was more than 100 times faster than that of the conventional low-pressure plasma CVD technique was realized.

Y. Mori; K. Yoshii; H. Kakiuchi; K. Yasutake

2000-01-01T23:59:59.000Z

207

Pyrolysis behavior of coal and petroleum coke at high temperature and high pressure.  

E-Print Network [OSTI]

??While pyrolysis of coal is a well-studied thermal process, little is known about pressurized pyrolysis of coal and petroleum coke. This study aims to interpret… (more)

Wagner, David Ray

2011-01-01T23:59:59.000Z

208

High-pressure xenon detector development at Constellation Technology Corporation  

Science Journals Connector (OSTI)

Xenon-filled ionization detectors, due to their high atomic number fill gas (Z=54), moderate densities (?0.3–0.5 g/cm3) and good energy resolution (2–4% at 662 keV), fill an important niche between more familiar technologies such as NaI(Tl) scintillators and germanium detectors. Until recently, difficulties with obtaining sufficient xenon purity, reducing microphonic sensitivity, and developing low-noise electronics compatible with small ionization signals have hampered the development of this nuclear detection field. Constellation Technology Corporation, whose experience with xenon detectors goes back to the mid 1990s, has made significant progress in these areas and has developed a commercial line of detectors with active volumes ranging from small (35 g Xe) to large (1400 g Xe). Current applications for Constellation's detectors are principally in the area of defense (Unmanned Aerial Vehicles and Advanced Spectroscopic Portals), but as awareness of this technology grows, it will surely find applications in a much expanded range of fields.

Robert A. Austin

2007-01-01T23:59:59.000Z

209

Structural phase transition in induced by swift heavy ion irradiation at high-pressure  

Science Journals Connector (OSTI)

Exposing pressurized crystals to GeV heavy ions reveals unexpected structural changes. Irradiated at ambient conditions, natural zirconia ( ZrO 2 ) transforms from the monoclinic structure to its tetragonal (high-temperature) phase. For this process the required fluence must exceed 5 × 10 12 ions / cm 2 for Pb and U and becomes even significantly higher for lighter ions. If samples are pressurized during irradiation using diamond anvil cells, the required fluence drops at least by one order of magnitude. The efficiency of the monoclinic to tetragonal phase transition becomes larger with increasing pressure.

B. Schuster; M. Lang; R. Klein; C. Trautmann; R. Neumann; A. Benyagoub

2009-01-01T23:59:59.000Z

210

Development of a High Pressure/High Temperature Down-hole Turbine Generator  

SciTech Connect (OSTI)

As oil & natural gas deposits become more difficult to obtain by conventional means, wells must extend to deeper more heat-intensive environments. The technology of the drilling equipment required to reach these depths has exceeded the availability of electrical power sources needed to operate these tools. Historically, logging while drilling (LWD) and measure while drilling (MWD) devices utilized a wireline to supply power and communication from the operator to the tool. Lithium ion batteries were used in scenarios where a wireline was not an option, as it complicated operations. In current downhole applications, lithium ion battery (LIB) packs are the primary source for electrical power. LIB technology has been proven to supply reliable downhole power at temperatures up to 175 °C. Many of the deeper well s reach ambient temperatures above 200 °C, creating an environment too harsh for current LIB technology. Other downfalls of LIB technology are cost, limitations on charge cycles, disposal issues and possible safety hazards including explosions and fires. Downhole power generation can also be achieved by utilizing drilling fluid flow and converting it to rotational motion. This rotational motion can be harnessed to spin magnets around a series of windings to produce power proportional to the rpm experienced by the driven assembly. These generators are, in most instances, driven by turbine blades or moyno-based drilling fluid pumps. To date, no commercially available downhole power generators are capable of operating at ambient temperatures of 250 °C. A downhole power g enerator capable of operation in a 250 °C and 20,000 psi ambient environment will be an absolute necessity in the future. Dexter Magnetic Technologies’ High-Pressure High-Temperature (HPHT) Downhole Turbine Generator is capable of operating at 250 °C and 20, 000 psi, but has not been tested in an actual drilling application. The technology exists, but to date no company has been willing to test the tool.

Ben Plamp

2008-06-30T23:59:59.000Z

211

Homogeneous carbon doping of magnesium diboride by high-temperature, high-pressure synthesis  

SciTech Connect (OSTI)

We have used high-pressure, high-temperature synthesis at 1500–1700?°C and 10?MPa to create homogeneously C-substituted MgB{sub 2} from a B{sub 4}C + Mg mixture. X-ray diffraction analysis showed large peak-shifts consistent with a decrease in the a lattice parameter for the B{sub 4}C-derived MgB{sub 2} as compared to an undoped sample (0.033–0.037?Å, depending on the sample). Microstructural investigation showed a three-phase mixture in the B{sub 4}C-derived ingots: MgB{sub 2?x}C{sub x} (with 0.178?

Susner, M. A., E-mail: susner.1@osu.edu; Bohnenstiehl, S. D.; Dregia, S. A.; Sumption, M. D.; Yang, Y.; Collings, E. W. [Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Donovan, J. J. [Center for Advanced Materials Characterization in Oregon (CAMCOR), University of Oregon, Eugene, Oregon 97403 (United States)

2014-04-21T23:59:59.000Z

212

Valve assembly for use with high temperature and high pressure fluids  

DOE Patents [OSTI]

The valve assembly for use with high temperature and high pressure fluids has inner and outer spaced shells and a valve actuator support of inner and outer spaced members which are connected at their end portions to the inner and outer shells, respectively, to extend substantially normal to the longitudinal axis of the inner shell. A layer of resilient heat insulating material covers the outer surfaces of the inner shell and the inner actuator support member and is of a thickness to only occupy part of the spaces between the inner and outer shells and inner and outer actuator support members. The remaining portion of the space between the inner and outer shells and the space between the inner and outer members is substantially filled with a body of castable, rigid refractory material. A movable valve member is disposed in the inner shell. A valve actuator assembly is supported in the valve actuator support to extend into the inner shell for connection with the movable valve member for movement of the movable valve member to positions from a fully open to a fully closed position to control flow of fluid through the inner shell. An anchor mneans is disposed adjacent opposite sides of the axis of the valve actuator support and attached to the inner shell so that relative radial movement between the inner and outer shell is permitted by the layer of resilient heat insulating material and relative longitudinal movement of the inner shell to the outer shell is permitted in opposite directions from the anchor means to thereby maintain the functional integrity of the movable valve member by providing an area of the inner shell surrounding the movable valve member longitdinally stationary, but at the same time allowing radial movement.

De Feo, Angelo (Totowa, NY)

1982-01-01T23:59:59.000Z

213

An RF-only ion-funnel for extraction from high-pressure gases  

E-Print Network [OSTI]

An RF ion-funnel technique has been developed to extract ions from a high-pressure (10 bar) noble-gas environment into vacuum ($10^{-6}$ mbar). Detailed simulations have been performed and a prototype has been developed for the purpose of extracting $^{136}$Ba ions from Xe gas with high efficiency. With this prototype, ions have been extracted for the first time from high-pressure xenon gas and argon gas. Systematic studies have been carried out and compared to the simulations. This demonstration of extraction of ions with mass comparable to that of the gas generating the high-pressure into vacuum has applications to Ba tagging from a Xe-gas time-projection chamber (TPC) for double beta decay as well as to the general problem of recovering trace amounts of an ionized element in a heavy (m$>40$ u) carrier gas.

Thomas Brunner; Daniel Fudenberg; Victor Varentsov; Amanda Sabourov; Giorgio Gratta; Jens Dilling; Ralph DeVoe; David Sinclair; William Fairbank Jr.; Joshua B Albert; David J Auty; Phil S Barbeau; Douglas Beck; Cesar Benitez-Medina; Martin Breidenbach; Guofu F Cao; Christopher Chambers; Bruce Cleveland; Matthew Coon; Adam Craycraft; Timothy Daniels; Sean J Daugherty; Tamar Didberidze; Michelle J Dolinski; Matthew Dunford; Lorenzo Fabris; Jacques Farine; Wolfhart Feldmeier; Peter Fierlinger; Razvan Gornea; Kevin Graham; Mike Heffner; Mitchell Hughes; Michael Jewell; Xiaoshan S Jiang; Tessa N Johnson; Sereres Johnston; Alexander Karelin; Lisa J Kaufman; Ryan Killick; Thomas Koffas; Scott Kravitz; Reiner Kruecken; Alexey Kuchenkov; Krishna S Kumar; Douglas S Leonard; Francois Leonard; Caio Licciardi; Yi-Hsuan H Lin; Jiajie Ling; Ryan MacLellan; Michael G Marino; Brian Mong; David Moore; Allen Odian; Igor Ostrovskiy; Christian Ouellet; Andreas Piepke; Andrea Pocar; Fabrice Retiere; Peter C Rowson; Maria P Rozo; Alexis Schubert; Erica Smith; Victor Stekhanov; Michal Tarka; Tamer Tolba; Delia Tosi; Karl Twelker; Jean-Luc L Vuilleumier; Josiah Walton; Timothy Walton; Manuel Weber; Liangjian J Wen; Ubi Wichoski; Liang Yang; Yung-Ruey Yen

2014-12-03T23:59:59.000Z

214

Raman spectroscopy on single and multi-walled nanotubes under high pressure  

E-Print Network [OSTI]

dependence of the high-energy Raman modes in single and multi-walled carbon nanotubes was measuredRaman spectroscopy on single and multi-walled nanotubes under high pressure C. Thomsen, S. Reich, H properties of carbon nanotubes have become of scienti c interest since it was recognized that the low atomic

Nabben, Reinhard

215

Structural phase transition in ZrO2 induced by swift heavy ion irradiation at high pressure  

E-Print Network [OSTI]

Structural phase transition in ZrO2 induced by swift heavy ion irradiation at high pressure B transition becomes larger with increasing pressure. Keywords: Zirconia, phase transition, high pressure-temperature poly- morphs (tetragonal and cubic) (see Fig 1). At about 1200 C, a martensitic-type phase transition

Paris-Sud XI, Université de

216

Standard test method for determination of susceptibility of metals to embrittlement in hydrogen containing environments at high pressure, high temperature, or both  

E-Print Network [OSTI]

Standard test method for determination of susceptibility of metals to embrittlement in hydrogen containing environments at high pressure, high temperature, or both

American Society for Testing and Materials. Philadelphia

1998-01-01T23:59:59.000Z

217

Experimental Assessment of Water Based Drilling Fluids in High Pressure and High Temperature Conditions  

E-Print Network [OSTI]

coming into effect, it becomes necessary to examine and understand the behavior of water based drilling fluids - which are cheaper and less polluting than their oil based counterpart - under extreme temperature and pressure conditions. In most...

Ravi, Ashwin

2012-10-19T23:59:59.000Z

218

Numerical simulation of the two-dimensional flow in high pressure catalytic combustor for gas turbine  

Science Journals Connector (OSTI)

The objective of this paper is modeling the mechanism of high pressure and high temperature catalytic oxidation of natural gas, or methane. The model is two-dimensional steady-state, and includes axial and radial convection and diffusion of mass, momentum and energy, as well as homogeneous (gas phase) and heterogeneous (gas surface) single step irreversible chemical reactions within a catalyst channel. Experimental investigations were also made of natural gas, or methane combustion in the presence of Mn-substituted hexaaluminate catalysts. Axial profiles of catalyst wall temperature, and gas temperature and gas composition for a range of gas turbine combustor operating conditions have been obtained for comparison with and development of a computer model of catalytic combustion. Numerical calculation results for atmospheric pressure agree well with experimental data. The calculations have been extended for high pressure (10 atm) operating conditions of gas turbine.

Y. Tsujikawa; S. Fujii; H. Sadamori; S. Ito; S. Katsura

1995-01-01T23:59:59.000Z

219

Cryogenic x-ray diffraction microscopy utilizing high-pressure cryopreservation  

Science Journals Connector (OSTI)

We present cryo x-ray diffraction microscopy of high-pressure-cryofixed bacteria and report high-convergence imaging with multiple image reconstructions. Hydrated D. radiodurans cells were cryofixed at 200 MPa pressure into ?10??m-thick water layers and their unstained, hydrated cellular environments were imaged by phasing diffraction patterns, reaching sub-30-nm resolutions with hard x-rays. Comparisons were made with conventional ambient-pressure-cryofixed samples, with respect to both coherent small-angle x-ray scattering and the image reconstruction. The results show a correlation between the level of background ice signal and phasing convergence, suggesting that phasing difficulties with frozen-hydrated specimens may be caused by high-background ice scattering.

Enju Lima; Yuriy Chushkin; Peter van der Linden; Chae Un Kim; Federico Zontone; Philippe Carpentier; Sol M. Gruner; Petra Pernot

2014-10-15T23:59:59.000Z

220

Crystal structure prediction and hydrogen-bond symmetrization of solid hydrazine under high pressure: a first-principles study  

Science Journals Connector (OSTI)

Three crystal structures of hydrazine under high pressure have been found, including the reported experimental phase. Pressure-induced hydrogen-bond symmetrization occurs at 235 GPa during the CcC2/c transition.

Zhang, H.-D.

2014-01-31T23:59:59.000Z

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


221

Dynamic compression of materials: metallization of fluid hydrogen at high pressures  

Science Journals Connector (OSTI)

Dynamic high pressure is 1?GPa (10?kbar) or greater with a rise time and a duration ranging from 1?ps (10?12?s) to 1?µs (10?6?s). Today it is possible in a laboratory to achieve pressures dynamically up to ~500?GPa (5?Mbar) and greater, compressions as much as ~15-fold greater than initial density in the case of hydrogen and temperatures from ~0.1 up to several electronvolts (11?600?K). At these conditions materials are extremely condensed semiconductors or degenerate metals. Temperature can be tuned independently of pressure by a combination of shock and isentropic compression. As a result, new opportunities are now available in condensed matter physics at extreme conditions. The basic physics of the dynamic process, experimental methods of generating and diagnosing matter at these extreme conditions and a technique to recover metastable materials intact from ~100?GPa shock pressures are discussed.Results include (i) generation of pressure standards at static pressures up to ~200?GPa (2?Mbar) at 300?K, (ii) single-shock compression of small-molecular fluids, including resolution of the recent controversy over the correct shock-compression curve of liquid D2 at 100?GPa pressures, (iii) the first observations of metallization of fluid hydrogen, nitrogen and oxygen compressed quasi-isentropically at 100?GPa pressures, (iv) implications for the interiors of giant planets within our solar system, extrasolar giant planets and brown dwarfs discovered recently and the equation of state of deuterium–tritium in inertial confinement fusion (ICF) and (v) prospects of recovering novel materials from extreme conditions, such as metastable solid metallic hydrogen. Future research is suggested.

W J Nellis

2006-01-01T23:59:59.000Z

222

Thermal conductance of metal-diamond interfaces at high pressure Gregory T. Hohensee  

E-Print Network [OSTI]

are concerned with the exchange of thermal energy across an interface between two materials. This topic-nonmetal interface, a two-temperature model predicts a thermal resistance of Rep = 1/ gL in series with the phononThermal conductance of metal-diamond interfaces at high pressure Gregory T. Hohensee Department

Cahill, David G.

223

Fast high-pressure freezing of protein crystals in their mother liquor  

Science Journals Connector (OSTI)

Protein crystals were vitrified using high-pressure freezing in their mother liquor at 210 MPa and 77 K without cryoprotectants or oil coating. The method was successfully applied to photosystem II, which is representative of a membrane protein with a large unit cell and weak crystal contacts.

Burkhardt, A.

2012-03-31T23:59:59.000Z

224

Anomalous elastic behavior and high-pressure structural evolution of zeolite levyne  

Science Journals Connector (OSTI)

...gatta@unimi.it Manuscript handled by Alison Pawley Elastic behavior and high-pressure...several authors (Sheppard et al. 1974; Wise and Tschernich 1976; Galli et al. 1981...Edition). Kluwer Academic, Dordrecht. Wise, W.S. and Tschernich, R.W. (1976...

Giacomo Diego Gatta; Paola Comodi; Pier Francesco Zanazzi; Tiziana Boffa Ballaran

225

Anticrack-associated faulting at very high pressure in natural olivine  

Science Journals Connector (OSTI)

... Publishing Group 10.1038/349264a0 Anticrack-associated faulting at very high pressure in natural olivineHarry W.GreenH. W.IIThomas E.YoungT. E.DavidWalkerD.Christopher H.ScholzC. H. Nature ...

Harry W. Green; Thomas E. Young; David Walker; Christopher H. Scholz

1991-01-17T23:59:59.000Z

226

ANALYSIS OF HIGH PRESSURE TESTS ON WET GAS FLOW METERING WITH A VENTURI METER  

E-Print Network [OSTI]

ANALYSIS OF HIGH PRESSURE TESTS ON WET GAS FLOW METERING WITH A VENTURI METER P. Gajan , Q, 64018 Pau cedex, France pierre.gajan@onera.fr Abstract This work deals with the flow metering of wet gas on the CEESI facilities are presented. They are performed at 75 bars with 0.6 beta ratio Venturi meter

227

Raman spectroscopy of Co,,OH...2 at high pressures: Implications for amorphization and hydrogen repulsion  

E-Print Network [OSTI]

.50. p, 63.20. e, 33.20.Fb, 33.20.Tp INTRODUCTION The high-pressure behavior of brucite-type hydroxides- itially much more compressible than the a axis. This is a general feature of the compression of brucite

Duffy, Thomas S.

228

Stability of very-high pressure arc discharges against perturbations of the electron temperature  

SciTech Connect (OSTI)

We study the stability of the energy balance of the electron gas in very high-pressure plasmas against longitudinal perturbations, using a local dispersion analysis. After deriving a dispersion equation, we apply the model to a very high-pressure (100 bar) xenon plasma and find instability for electron temperatures, T{sub e}, in a window between 2400 K and 5500-7000 K x 10{sup 3} K, depending on the current density (10{sup 6}-10{sup 8} A/m{sup 2}). The instability can be traced back to the Joule heating of the electron gas being a growing function of T{sub e}, which is due to a rising dependence of the electron-atom collision frequency on T{sub e}. We then analyze the T{sub e} range occurring in very high-pressure xenon lamps and conclude that only the near-anode region exhibits T{sub e} sufficiently low for this instability to occur. Indeed, previous experiments have revealed that such lamps develop, under certain conditions, voltage oscillations accompanied by electromagnetic interference, and this instability has been pinned down to the plasma-anode interaction. A relation between the mechanisms of the considered instability and multiple anodic attachments of high-pressure arcs is discussed.

Benilov, M. S. [Departamento de Fisica, Ciencias Exactas e Engenharia, Universidade da Madeira, Largo do Municipio, Funchal 9000 (Portugal); Hechtfischer, U. [Philips Lighting, BU Automotive Lamps, Technology, Philipsstrasse 8, Aachen 52068 (Germany)

2012-04-01T23:59:59.000Z

229

OPTIMAL DESIGN OF A HIGH PRESSURE ORGANOMETALLIC CHEMICAL VAPOR DEPOSITION REACTOR  

E-Print Network [OSTI]

OPTIMAL DESIGN OF A HIGH PRESSURE ORGANOMETALLIC CHEMICAL VAPOR DEPOSITION REACTOR K.J. BACHMANN of computer simulations as an optimal design tool which lessens the costs in time and effort in experimental vapor deposition (HPOMCVD) reactor for use in thin film crystal growth. The advantages of such a reactor

230

Investigations on the Failure of Economizer Tubes in a High-Pressure Boiler  

Science Journals Connector (OSTI)

This article describes the results of an investigation concerning the failure of economizer tubes of a high-pressure boiler in ... . The cause of the failure of the economizer tube appears to be H2SO4 dew-point c...

M. Mobin; A. U. Malik; M. Al-Hajri

2008-02-01T23:59:59.000Z

231

Ultrafast high-pressure AC electro-osmotic pumps for portable biomedical microfluidics  

E-Print Network [OSTI]

Ultrafast high-pressure AC electro-osmotic pumps for portable biomedical microfluidics Chien details the development of an integrated AC electro-osmotic (ACEO) microfluidic pump for dilute (100 mM) biological solutions in separate microfluidic devices, with potential applications in portable

Bazant, Martin Z.

232

Metastable high-pressure transformations of orthoferrosilite Fs82 Przemyslaw Dera a,e,  

E-Print Network [OSTI]

Metastable high-pressure transformations of orthoferrosilite Fs82 Przemyslaw Dera a,e, , Gregory J Institution of Washington, USA e Hawaii Institute of Geophysics and Planetology, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, USA a r t i c l e i n f o Article history: Received

Duffy, Thomas S.

233

High-pressure structural studies of dysprosium using angle-dispersive x-ray diffraction  

SciTech Connect (OSTI)

We present structural results under pressure for elemental dysprosium (Dy) up to 87 GPa using in situ angle-dispersive x-ray diffraction measurements with synchrotron x rays and a diamond-anvil cell. Dy exhibits the structural transition sequence, hP2{yields}hR9{yields}hP4{yields}distorted cF4, from Rietveld full-profile refinements. Clear evidence is documented for the high-pressure distorted cF4 phase observed above 45 GPa to be an orthorhombic oS8 (Cmmm) structure for Dy in the lanthanide phase diagram.

Shen Yongrong; Kumar, Ravhi S.; Cornelius, Andrew L.; Nicol, Malcolm F. [Department of Physics and High Pressure Science and Engineering Center, University of Nevada Las Vegas, Las Vegas, Nevada 89154-4002 (United States)

2007-02-01T23:59:59.000Z

234

Raman Spectroscopy of SiO2 Glass at High Pressure  

Science Journals Connector (OSTI)

A new technique has been developed for optical studies of amorphous solids to very high pressures. Raman spectra of SiO2 glass measured at 8 GPa indicate a significant reduction in the width of the Si-O-Si angle distribution, which has been associated with a number of anomalous properties of silica glass under ambient conditions. Between 8 and ? 30 GPa irreversible changes in the Raman spectrum occur that are consistent with a shift in ring statistics in densified glass. The spectra suggest a breakdown in intermediate-range order at higher pressure.

R. J. Hemley; H. K. Mao; P. M. Bell; B. O. Mysen

1986-08-11T23:59:59.000Z

235

Unexpectedly high pressure for molecular dissociation in liquid hydrogen by a reliable electronic simulation  

E-Print Network [OSTI]

The study of the high pressure phase diagram of hydrogen has continued with renewed effort for about one century as it remains a fundamental challenge for experimental and theoretical techniques. Here we employ an efficient molecular dynamics based on the quantum Monte Carlo method, which can describe accurately the electronic correlation and treat a large number of hydrogen atoms, allowing a realistic and reliable prediction of thermodynamic roperties. We find that the molecular liquid phase is unexpectedly stable and the transition towards a fully atomic liquid phase occurs at much higher pressure than previously believed. The old standing problem of low temperature atomization is, therefore, still far from experimental reach.

Mazzola, Guglielmo; Sorella, Sandro

2014-01-01T23:59:59.000Z

236

Influence of viscosity modifier nature and concentration on the viscous flow behaviour of oil-based drilling fluids at high pressure  

Science Journals Connector (OSTI)

Abstract This work deals with the effect of viscosity modifier nature and concentration on the rheological properties of model oil-based drilling fluids (OBM) submitted to high pressure. The oil-based fluids were formulated by dispersing, with a high shear mixer, two selected organobentonites in a mineral oil, at room temperature. The viscous flow behaviour of the corresponding dispersions was characterised as a function of pressure, organoclay nature and organoclay concentration, using a controlled-stress rheometer equipped with both pressure cell and coaxial cylinder geometries. A factorial Sisko–Barus model, which takes into account both shear and pressure effects in the same equation, fitted the experimental pressure–viscosity data fairly well. The influence of disperse phase concentration on the shear-thinning characteristics of these organoclay dispersions is related to the development of different microstructures, which depend on organoclay nature. In this sense, the resulting microstructure has been attributed to the cohesion energy between microgels domains. From the experimental results obtained, it can be concluded that the viscous flow behaviour of the OBM investigated is strongly affected by organoclay nature and concentration. The pressure–viscosity behaviour of these dispersions is mainly influenced by the piezoviscous properties of the oil and the properties of the continuous phase. The Sisko–Barus model proposed can be a useful tool, from an engineering point of view, for calculating pressure losses in the different sections of the bore, as well as being of significant help to solve other additional problems, such as hole cleaning, induced fracturing, and hole erosion during the drilling operation.

J. Hermoso; F. Martinez-Boza; C. Gallegos

2014-01-01T23:59:59.000Z

237

Innovative high pressure gas MEM's based neutron detector for ICF and active SNM detection.  

SciTech Connect (OSTI)

An innovative helium3 high pressure gas detection system, made possible by utilizing Sandia's expertise in Micro-electrical Mechanical fluidic systems, is proposed which appears to have many beneficial performance characteristics with regards to making these neutron measurements in the high bremsstrahlung and electrical noise environments found in High Energy Density Physics experiments and especially on the very high noise environment generated on the fast pulsed power experiments performed here at Sandia. This same system may dramatically improve active WMD and contraband detection as well when employed with ultrafast (10-50 ns) pulsed neutron sources.

Martin, Shawn Bryan; Derzon, Mark Steven; Renzi, Ronald F.; Chandler, Gordon Andrew

2007-12-01T23:59:59.000Z

238

Manufacturing and properties of newly developed 9%CrMoVNiNbN high-pressure low-pressure rotor shaft forging  

SciTech Connect (OSTI)

In order to obtain the improved strength and toughness for high-pressure low-pressure rotor shaft forging, fundamental studies using laboratory heats were performed on the 9CrMoV base materials, and effects of chemistry on toughness and creep rupture strength were investigated. From the investigation, it is showed that the superclean 9CrMoVNiNbN steel with reduced Si and Mn contents and Ni addition provides a superior strength versus toughness balance. Based on these fundamental studies, a trial high-pressure low-pressure rotor shaft forging with diameter of low-pressure section of 1,750 mm and diameter of high-pressure section of 1,200 mm was successfully manufactured from the diameter of 1,800 mm, and the weight of 65 ton ESR ingot. From the evaluation test results of this trial rotor forging, homogeneous distribution of chemistry was confirmed and low impurity contents was observed in the whole forging. The superior strength and toughness were confirmed with good creep rupture strength. The FATT at the center of low-pressure section was {minus}3 C with the tensile strength level of 870 MPa. From the results of fracture toughness test, low cycle fatigue test, and isothermal aging test, superior mechanical properties were demonstrated. Thus, the superclean 9CrMoVNiNbN steel with reduced Si and Mn contents and Ni addition, is particularly suitable for the high-pressure low-pressure rotor material for advanced combined cycle power plants.

Azuma, Tsukasa; Tanaka, Yasuhiko; Ishiguro, Tohru; Yoshida, Hajime; Ikeda, Yasumi [Japan Steel Works, Muroran (Japan)

1997-12-31T23:59:59.000Z

239

Studies on the effects of heat and high pressure treatmeants on fat globule surface layers in recombined milk.  

E-Print Network [OSTI]

??The present study examined the effects of heat treatment, high pressure (HP) treatment or combined heat and HP treatments, either before or after homogenization, on… (more)

Anantawat, Visaka

2011-01-01T23:59:59.000Z

240

A CFD Model for High Pressure Liquid Poison Injection for CANDU-6 Shutdown System No. 2  

SciTech Connect (OSTI)

In CANDU reactor one of the two reactor shutdown systems is the liquid poison injection system which injects the highly pressurized liquid neutron poison into the moderator tank via small holes on the nozzle pipes. To ensure the safe shutdown of a reactor it is necessary for the poison curtains generated by jets provide quick, and enough negative reactivity to the reactor during the early stage of the accident. In order to produce the neutron cross section necessary to perform this work, the poison concentration distribution during the transient is necessary. In this study, a set of models for analyzing the transient poison concentration induced by this high pressure poison injection jet activated upon the reactor trip in a CANDU-6 reactor moderator tank has been developed and used to generate the poison concentration distribution of the poison curtains induced by the high pressure jets injected into the vacant region between the pressure tube banks. The poison injection rate through the jet holes drilled on the nozzle pipes is obtained by a 1-D transient hydrodynamic code called, ALITRIG, and this injection rate is used to provide the inlet boundary condition to a 3-D CFD model of the moderator tank based on CFX4.3, a CFD code, to simulate the formation of the poison jet curtain inside the moderator tank. For validation, an attempt was made to validate this model against a poison injection experiment performed at BARC. As conclusion this set of models is judged to be appropriate. (authors)

Bo Wook Rhee; Chang Jun Jeong [Korea Atomic Energy Research Institute, 150, Dukjin-Dong, Yusong-Gu, Taejon 305-353 (Korea, Republic of); Hye Jeong Yun; Dong Soon Jang [Choongnam National University, Daejeon 305-764 (Korea, Republic of)

2002-07-01T23:59:59.000Z

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


241

Use of high hydrostatic pressure to produce high quality and safe fresh pork sausage  

E-Print Network [OSTI]

and Functionality Improvement . . . . . . . . . . . . . . . . . . . . . Thermal Processing . Response Surface Methodology 22 22 22 23 23 24 26 26 27 30 32 111 THEORETICAL CONSIDERATIONS 33 31 3. 2 3. 3 Theory of Linear Viscoelasticity 3. 1. 1... with yeast extract (TSA) and Modified oxford agar (MOX) with supplements . . . . . . . . . . . . . . . . 73 5. 2 Survival of three individual strains of L. monocytogenes in fresh pork sausage exposed to a hydrostatic pressure of 414 MPa at 25'C for various...

Huang, Mei

2012-06-07T23:59:59.000Z

242

Experimental Investigation on High-pressure, High-temperature Viscosity of Gas Mixtures  

E-Print Network [OSTI]

area A a layer in fluid flow between two plates bar pressure unit, 1 bar = 0.987 atms cm centimeter cp centipoise CO2 carbon dioxide oC Celsius temperature db ball diameter dt tube diameter D tube diameter ft foot or feet F... Subscripts Symbol Description 1atm 1 atmosphere Avg average CO2 carbon dioxide g gas H2S hydrogen sulfide i initial N2 nitrogen xiii TABLE OF CONTENTS Page ABSTRACT...

Davani, Ehsan

2012-02-14T23:59:59.000Z

243

NETL: Staged, High-Pressure Oxy-Combustion Technology: Development and  

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

Oxy-Combustion CO2 Emissions Control Oxy-Combustion CO2 Emissions Control Staged, High-Pressure Oxy-Combustion Technology: Development and Scale-up Project No.: DE-FE0009702 Washington University in St. Louis is developing a unique pressurized system to capture carbon from coal-fired power plants that incorporates a fuel-staged combustion approach. By staging the combustion, the temperature and heat transfer can be controlled. The potential benefits of the process are: higher efficiency, reduced process gas volume, increased radiative heat transfer, reduced oxygen demands, reduced capital equipment costs, increased CO2 purity entering the carbon compression and purification unit, and reduced auxiliary power demands. These benefits are expected to yield a lower cost of electricity than alternative approaches to pressurized oxy-combustion.

244

The High-Pressure Characterization of Energetic Materials: 2-Methyl-5-Nitramino-2H-Tetrazole  

SciTech Connect (OSTI)

The isothermal structural properties, equation of state, and vibrational dynamics of 2MNT were studied under high-pressure using synchrotron XRD and optical Raman and IR microspectroscopy. Analysis of the XRD patterns revealed no indication of a phase transition to near 15 GPa and the pressure-volume isotherm remained smooth to 15 GPa. Near 15 GPa, significant sample damage was observed from the X-ray beam which precluded the acquisition of patterns above this pressure. XRD and Raman spectroscopic measurements showed the monoclinic ambient condition phase of 2MNT remains the dominant phase to near 20 GPa, although a shift of the NO{sub 2} IR active vibrational modes to lower frequencies suggested a subtle geometry modification not reflected in the XRD data.

J Ciezak

2011-12-31T23:59:59.000Z

245

Autoignition of gasoline surrogates mixtures at intermediate temperatures and high pressures  

SciTech Connect (OSTI)

Ignition times were determined in high-pressure shock-tube experiments for various stoichiometric mixtures of two multicomponent model fuels in air for the validation of ignition delay simulations based on chemical kinetic models. The fuel blends were n-heptane (18%)/isooctane (62%)/ethanol (20%) by liquid volume (14.5%/44.5%/41% by mole fraction) and n-heptane (20%)/toluene (45%)/isooctane (25%)/diisobutylene (10%) by liquid volume (17.5%/55%/19.5%/8.0% by mole fraction). These fuels have octane numbers comparable to a standard European gasoline of 95 RON and 85 MON. The experimental conditions cover temperatures from 690 to 1200 K and pressures at 10, 30, and 50 bar. The obtained ignition time data are scaled with respect to pressure and compared to previous results reported in the literature. (author)

Fikri, M.; Herzler, J.; Starke, R.; Schulz, C.; Roth, P. [IVG, Universitaet Duisburg-Essen, D-47048 Duisburg (Germany); Kalghatgi, G.T. [Shell Global Solutions U.K., P.O. Box 1, Chester CH1 3SH (United Kingdom)

2008-01-15T23:59:59.000Z

246

High pressure sulfuric acid decomposition experiments for the sulfur-iodine thermochemical cycle.  

SciTech Connect (OSTI)

A series of three pressurized sulfuric acid decomposition tests were performed to (1) obtain data on the fraction of sulfuric acid catalytically converted to sulfur dioxide, oxygen, and water as a function of temperature and pressure, (2) demonstrate real-time measurements of acid conversion for use as process control, (3) obtain multiple measurements of conversion as a function of temperature within a single experiment, and (4) assess rapid quenching to minimize corrosion of metallic components by undecomposed acid. All four of these objectives were successfully accomplished. This report documents the completion of the NHI milestone on high pressure H{sub 2}SO{sub 4} decomposition tests for the Sulfur-Iodine (SI) thermochemical cycle project. All heated sections of the apparatus, (i.e. the boiler, decomposer, and condenser) were fabricated from Hastelloy C276. A ceramic acid injection tube and a ceramic-sheathed thermocouple were used to minimize corrosion of hot liquid acid on the boiler surfaces. Negligible fracturing of the platinum on zirconia catalyst was observed in the high temperature decomposer. Temperature measurements at the exit of the decomposer and at the entry of the condenser indicated that the hot acid vapors were rapidly quenched from about 400 C to less than 20 C within a 14 cm length of the flow path. Real-time gas flow rate measurements of the decomposition products provided a direct measurement of acid conversion. Pressure in the apparatus was preset by a pressure-relief valve that worked well at controlling the system pressure. However, these valves sometimes underwent abrupt transitions that resulted in rapidly varying gas flow rates with concomitant variations in the acid conversion fraction.

Velasquez, Carlos E; Reay, Andrew R.; Andazola, James C.; Naranjo, Gerald E.; Gelbard, Fred

2005-09-01T23:59:59.000Z

247

A high-pressure atomic force microscope for imaging in supercritical carbon dioxide  

SciTech Connect (OSTI)

A high-pressure atomic force microscope (AFM) that enables in situ, atomic scale measurements of topography of solid surfaces in contact with supercritical CO{sub 2} (scCO{sub 2}) fluids has been developed. This apparatus overcomes the pressure limitations of the hydrothermal AFM and is designed to handle pressures up to 100 atm at temperatures up to ?350 K. A standard optically-based cantilever deflection detection system was chosen. When imaging in compressible supercritical fluids such as scCO{sub 2} , precise control of pressure and temperature in the fluid cell is the primary technical challenge. Noise levels and imaging resolution depend on minimization of fluid density fluctuations that change the fluid refractive index and hence the laser path. We demonstrate with our apparatus in situ atomic scale imaging of a calcite (CaCO{sub 3}) mineral surface in scCO{sub 2}; both single, monatomic steps and dynamic processes occurring on the (10{overbar 1}4) surface are presented. This new AFM provides unprecedented in situ access to interfacial phenomena at solid–fluid interfaces under pressure.

Lea, A.S.; Higgins, S.R.; Knauss, K.G.; Rosso, K.M.

2011-01-15T23:59:59.000Z

248

Comparison of high pressure transient PVT measurements and model predictions. Part I.  

SciTech Connect (OSTI)

A series of experiments consisting of vessel-to-vessel transfers of pressurized gas using Transient PVT methodology have been conducted to provide a data set for optimizing heat transfer correlations in high pressure flow systems. In rapid expansions such as these, the heat transfer conditions are neither adiabatic nor isothermal. Compressible flow tools exist, such as NETFLOW that can accurately calculate the pressure and other dynamical mechanical properties of such a system as a function of time. However to properly evaluate the mass that has transferred as a function of time these computational tools rely on heat transfer correlations that must be confirmed experimentally. In this work new data sets using helium gas are used to evaluate the accuracy of these correlations for receiver vessel sizes ranging from 0.090 L to 13 L and initial supply pressures ranging from 2 MPa to 40 MPa. The comparisons show that the correlations developed in the 1980s from sparse data sets perform well for the supply vessels but are not accurate for the receivers, particularly at early time during the transfers. This report focuses on the experiments used to obtain high quality data sets that can be used to validate computational models. Part II of this report discusses how these data were used to gain insight into the physics of gas transfer and to improve vessel heat transfer correlations. Network flow modeling and CFD modeling is also discussed.

Felver, Todd G.; Paradiso, Nicholas Joseph; Evans, Gregory Herbert; Rice, Steven F.; Winters, William Stanley, Jr.

2010-07-01T23:59:59.000Z

249

X-ray Diffraction of Cubic Gd2)3/Er under High Pressure  

SciTech Connect (OSTI)

In this paper, we report the in situ high pressure X-ray diffraction studies on Er{sup 3+} doped Gd{sub 2}O{sub 3} in a diamond anvil cell up to 39.8 GPa at room temperature. Several phase transitions have been identified in our studies. The structural transformation from a starting cubic phase to a hexagonal phase occurred during the sample compression process, at 8.57 GPa. And the hexagonal phase was stable from 12.5 GPa up to the highest pressure in this study but was not quenchable and transformed to a monoclinic phase after pressure release. An anomalous high pressure behavior in the hexagonal type Gd{sub 2}O{sub 3} phase was observed, which might be caused by an electron transition influenced by Er{sup 3+} ions doping. By fitting the compression data to the Birch-Murnaghan equation of state, the bulk moduli of the cubic and two hexagonal (at p < 19.9 GPa and p > 27.0 GPa) Gd{sub 2}O{sub 3} phases were determined to be 164 {+-} 3, 185 {+-} 7, and 150 {+-} 10 GPa with B'{sub 0} = 4, respectively.

X Zou; C Gong; B Liu; Q Li; Z Li; B Liu; R Liu; J Liu; Z Chen; et al.

2011-12-31T23:59:59.000Z

250

High pressure pair distribution function studies of Green River oil shale.  

SciTech Connect (OSTI)

The compression behavior of a silicate-rich oil shale from the Green River formation in the pressure range 0.0-2.4 GPa was studied using in situ high pressure X-ray pair distribution function (PDF) measurements for the sample contained within a Paris-Edinburgh cell. The real-space local structural information in the PDF, G(r), was used to evaluate the compressibility of the oil shale. Specifically, the pressure-induced reduction in the medium- to long-range atom distances ({approx}6-20 {angstrom}) yielded an average sample compressibility corresponding to a bulk modulus of ca. 61-67 GPa. A structural model consisting of a three phase mixture of the principal crystalline oil shale components (quartz, albite and Illite) provided a good fit to the ambient pressure PDF data (R {approx} 30.7%). Indeed the features in the PDF beyond {approx} {angstrom}, were similarly well fit by a single phase model of the highest symmetry, highly crystalline quartz component. The factors influencing the observed compression behavior are discussed.

Chapman, K. W.; Chupas, P. J.; Locke, D. R.; Winans, R. E.; Pugmire, R. J.; Univ. of Utah

2008-01-01T23:59:59.000Z

251

Pulse Rise Time Characterization of a High Pressure Xenon Gamma Detector for use in Resolution Enhancement  

SciTech Connect (OSTI)

High pressure xenon ionization chamber detectors are possible alternatives to traditional thallium doped sodium iodide (NaI(Tl)) and hyperpure germanium as gamma spectrometers in certain applications. Xenon detectors incorporating a Frisch grid exhibit energy resolutions comparable to cadmium/zinc/telluride (CZT) (e.g. 2% {at} 662keV) but with far greater sensitive volumes. The Frisch grid reduces the position dependence of the anode pulse risetimes, but it also increases the detector vibration sensitivity, anode capacitance, voltage requirements and mechanical complexity. We have been investigating the possibility of eliminating the grid electrode in high-pressure xenon detectors and preserving the high energy resolution using electronic risetime compensation methods. A two-electrode cylindrical high pressure xenon gamma detector coupled to time-to-amplitude conversion electronics was used to characterize the pulse rise time of deposited gamma photons. Time discrimination was used to characterize the pulse rise time versus photo peak position and resolution. These data were collected to investigate the effect of pulse rise time compensation on resolution and efficiency.

TROYER, G.L.

2000-08-25T23:59:59.000Z

252

High Pressure Fuel Storage Cylinders Periodic Inspection and End of Life Issues  

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

6/2010 6/2010 www.cleanvehicle.org 1 High Pressure Fuel Storage Cylinders Periodic Inspection and End of Life Issues DOE Vehicular Tank Workshop April 29, 2010 Douglas Horne, PE The Facts  High pressure Type 4 gaseous fuel tanks are now designed under standards that specify finite lifetimes of 15, 20 and 25 years based on specific design and testing (the HGV2 standard under development had a life as short as 10 years as an option)  It is unique within the transportation industry to have a critical device (the fuel tank) with a designated life that may be shorter than the vehicle itself  Although vehicle owners are told up front of the limited life fuel storage cylinders some tend to forget after 15 years  A parallel concern is the requirement for these fuel tanks

253

Highly efficient oxidation of silicon at low temperatures using atmospheric pressure plasma  

Science Journals Connector (OSTI)

Silicon oxide ( Si O 2 ) layers were formed with initial oxidation rates in the range of 6.2 – 14.1 nm ? min in the temperature range of 150 – 400 ° C by oxidizing Si(001) wafers. Such a high-rate and low-temperature oxidation was realized by using a stable glow He ? O 2 plasma excited at atmospheric pressure by a 150 MHz very high-frequency power. Increasing the temperature led to both the higher oxidation rate and the better quality of Si O 2 and Si O 2 ? Si interface. The oxidation at 400 ° C showed an interface trap density of 6.2 × 10 10 eV ? 1 cm ? 2 which is considerably lower than that in a radical oxidation process using low-pressure He ? O 2 plasma at the same temperature.

Hiroaki Kakiuchi; Hiromasa Ohmi; Makoto Harada; Heiji Watanabe; Kiyoshi Yasutake

2007-01-01T23:59:59.000Z

254

Highly efficient oxidation of silicon at low temperatures using atmospheric pressure plasma  

SciTech Connect (OSTI)

Silicon oxide (SiO{sub 2}) layers were formed with initial oxidation rates in the range of 6.2-14.1 nm/min in the temperature range of 150-400 deg. C by oxidizing Si(001) wafers. Such a high-rate and low-temperature oxidation was realized by using a stable glow He/O{sub 2} plasma excited at atmospheric pressure by a 150 MHz very high-frequency power. Increasing the temperature led to both the higher oxidation rate and the better quality of SiO{sub 2} and SiO{sub 2}/Si interface. The oxidation at 400 deg. C showed an interface trap density of 6.2x10{sup 10} eV{sup -1} cm{sup -2}, which is considerably lower than that in a radical oxidation process using low-pressure He/O{sub 2} plasma at the same temperature.

Kakiuchi, Hiroaki; Ohmi, Hiromasa; Harada, Makoto; Watanabe, Heiji; Yasutake, Kiyoshi [Department of Precision Science and Technology, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan)

2007-02-26T23:59:59.000Z

255

Engineering properties of miniature cement - fly ash compacts prepared by high pressure compaction  

E-Print Network [OSTI]

ENGINEERING PROPERTIES OF MINIATURE CEMENT - FLY ASH COMPACTS PREPARED BY HIGH PRESSURE COMPACTION E NGIRPR OT SFMMAFU AEU C-ALEYY HDOBPvvIi va vGI ge(iD(vI oannItI au NId(R E)L xrP1IeRPvT 9(evP(n uDnuPnnBIrv au vGI eI0DPeIBIrvR uae vGI i...IteII au LEHNFA -M Ho2FYoF EDtDRv 3456 L(7ae HDO7I8v? oP1Pn FrtPrIIePrt ENGINEERING PROPERTIES OF MINIATURE CEMENT - FLY ASH COMPACTS PREPARED BY HIGH PRESSURE COMPACTION E NGIRPR OT SFMMAFU AEU C-ALEYY E99ea1Ii (R va RvTnI (ri 8arvIrv OT? LP...

Bormann, Jeffrey Ray

1985-01-01T23:59:59.000Z

256

High Pressure Water Jet System Performance Assessment Project A-2A  

SciTech Connect (OSTI)

Performance assessment for canister cleaning system in the KE Basin. Information obtained from this assessment will be used to design any additional equipment used to clean canisters. After thorough review of the design, maintenance history and operational characteristics of the 105 K East (KE) canister cleaning system, Bartlett recommends that the high pressure water jet system (HPWJS) be modified as outlined in section 5.0, and retained for future use. Further, it is recommended that Spent Nuclear Fuel (SNF) Project consider use of a graded approach for canister cleaning, based on individual canister type and characteristics. This approach would allow a simple method to be used on canisters not needing the more rigorous, high-pressure method. Justification is provided in section 5.0. Although Bartlett has provided some preliminary cost estimates, it is recommended that SNF Project perform a detailed cost-benefit analysis to weigh the alternatives presented.

FARWICK, C.C.

1999-12-03T23:59:59.000Z

257

Ground state properties and high pressure behavior of plutonium dioxide: Systematic density functional calculations  

E-Print Network [OSTI]

Plutonium dioxide is of high technological importance in nuclear fuel cycle and is particularly crucial in long-term storage of Pu-based radioactive waste. Using first-principles density-functional theory, in this paper we systematically study the structural, electronic, mechanical, thermodynamic properties, and pressure induced structural transition of PuO$_{2}$. To properly describe the strong correlation in the Pu $5f$ electrons, the local density approximation$+U$ and the generalized gradient approximation$+U$ theoretical formalisms have been employed. We optimize the $U$ parameter in calculating the total energy, lattice parameters, and bulk modulus at the nonmagnetic, ferromagnetic, and antiferromagnetic configurations for both ground state fluorite structure and high pressure cotunnite structure. The best agreement with experiments is obtained by tuning the effective Hubbard parameter $U$ at around 4 eV within the LDA$+U$ approach. After carefully testing the validity of the ground state, we further in...

Zhang, Ping; Zhao, Xian-Geng

2010-01-01T23:59:59.000Z

258

The NEXT experiment: A high pressure xenon gas TPC for neutrinoless double beta decay searches  

E-Print Network [OSTI]

Neutrinoless double beta decay is a hypothetical, very slow nuclear transition in which two neutrons undergo beta decay simultaneously and without the emission of neutrinos. The importance of this process goes beyond its intrinsic interest: an unambiguous observation would establish a Majorana nature for the neutrino and prove the violation of lepton number. NEXT is a new experiment to search for neutrinoless double beta decay using a radiopure high-pressure xenon gas TPC, filled with 100 kg of Xe enriched in Xe-136. NEXT will be the first large high-pressure gas TPC to use electroluminescence readout with SOFT (Separated, Optimized FuncTions) technology. The design consists in asymmetric TPC, with photomultipliers behind a transparent cathode and position-sensitive light pixels behind the anode. The experiment is approved to start data taking at the Laboratorio Subterr\\'aneo de Canfranc (LSC), Spain, in 2014.

D. Lorca; J. Martín-Albo; F. Monrabal; for the NEXT Collaboration

2012-10-15T23:59:59.000Z

259

Computations of high-pressure steam flow in the turbine bypass valve  

SciTech Connect (OSTI)

The objective of the present study is to investigate the steam flow behavior through the high-pressure turbine bypass valve. Efforts have mainly been directed at investigating the process of steam flow and property variations aforementioned bypass valve as well as to obtain correlations between the flow rate and the valve opening ratio. Modeling of the high-pressure turbulent steam flow was performed on a three-dimensional non-staggered grid system by employing the finite volume method and by solving the three-dimensional, turbulent, compressible Navier-Stokes, and energy equations. Through this research, numerous data have been acquired and analyzed. These efforts enable one to obtain a correlation data set for the valve opening versus flow rate coefficient of the valve. One of the significant accomplishments is to use the model presented here to further improve a design of a turbine bypass flow valve.

Amano, R.S.; Draxler, G.R.

1999-07-01T23:59:59.000Z

260

Development of Kinetics and Mathematical Models for High Pressure Gasification of Lignite-Switchgrass Blends  

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

Kinetics and Mathematical Kinetics and Mathematical Models for High Pressure Gasification of Lignite-Switchgrass Blends Background Significant progress has been made in recent years in controlling emissions resulting from coal-fired electricity generation in the United States through the research, development, and deployment of innovative technologies such as gasification. Gasification is a process that converts solid feedstocks such as coal, biomass, or blends

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261

Investigation of a high pressure implosive technique for metal powder compaction  

E-Print Network [OSTI]

Permanent Address ? 314 Brookside Dr. , Bryan, Texas 77801 Donald R. Garrett received his Bachelor of Science degree from the United States Military Academy in 1958. Mr. Garrett was a military training instructor in the U. S. A. F. and a jet aircraft in...INVESTIGATION OF A HIGH PRESSURE IMPLOSIVE TECHNIQUE FOR METAL POWDER COMPACTION A Thesis DONALD RICHARD GARRETT Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER...

Garrett, Donald Richard

1970-01-01T23:59:59.000Z

262

Turbulence sets the initial conditions for star formation in high-pressure environments  

E-Print Network [OSTI]

Despite the simplicity of theoretical models of supersonically turbulent, isothermal media, their predictions successfully match the observed gas structure and star formation activity within low-pressure (P/k 10^7 K cm^-3) environments, like those in the Galaxy's inner 200 pc Central Molecular Zone (CMZ) and in the early Universe. Here we present ALMA 3mm dust continuum emission within a cloud, G0.253+0.016, which is immersed in the high-pressure environment of the CMZ. While the log-normal shape and dispersion of its column density PDF is strikingly similar to those of solar neighbourhood clouds, there is one important quantitative difference: its mean column density is 1--2 orders of magnitude higher. Both the similarity and difference in the PDF compared to those derived from solar neighbourhood clouds match predictions of turbulent cloud models given the high-pressure environment of the CMZ. The PDF shows a small deviation from log-normal at high column densities confirming the youth of G0.253+0.016. Its...

Rathborne, J M; Jackson, J M; Kruijssen, J M D; Alves, J F; Bally, J; Bastian, N; Contreras, Y; Foster, J B; Garay, G; Testi, L; Walsh, A J

2014-01-01T23:59:59.000Z

263

Fusion Curve of Europium, Fusion, and fcc-bcc Transformation in Ytterbium at High Pressures  

Science Journals Connector (OSTI)

The melting behavior of Eu to 70 kbar and melting and fcc-bcc transformation in Yb to 40 kbar have been studied. Europium has a maximum in the fusion curve at about 35 kbar and 995°C and retains the bcc structure in the pressure and temperature range investigated. The fusion curve of Yb has an initial slope of 19°/kbar and rapidly flattens in the 35-kbar region. There appears to be only one fcc-bcc phase boundary and not two as proposed in an earlier study. This boundary intersects the temperature axis close to the known fcc-bcc transformation temperature at atmospheric pressure, and an initial slope of -16°/kbar is suggested. This transformation in Yb behaves exactly like the analogous transformation in Sr, exhibiting pressure and temperature hysteresis and also reversing the sign of the resistance discontinuity above 24 kbar. The striking parallelism in high-pressure behavior between Eu and Ba and Yb and Sr is discussed. The greater density of the bcc phase compared to fcc or hcp noted in several instances is rationalized. The melting behavior of Eu is discussed from the standpoint of coordination in the liquid state.

A. Jayaraman

1964-08-17T23:59:59.000Z

264

Effects of high pressure-dependent leakoff and high process-zone stress in coal-stimulation treatments  

SciTech Connect (OSTI)

Hydraulic fracturing in coals has been studied extensively over the last two decades; however, there are factors that were often ignored or incorrectly diagnosed, resulting in screenouts. Assuming that a majority of the perforations are open and there are no problems with the stimulation fluids, screenouts during coal hydraulic-fracture treatments can be attributed to either high pressure-dependent leakoff (PDL), high process-zone stress (PZS) or in some cases both. The objective of this work is to discuss, help identify, and present solutions to address these reservoir-related issues such that screenouts can be avoided in optimized refracture treatments and new well stimulations. The tools for identifying these reservoir-related parameters include a diagnostic fracture-injection test (DFIT) and a grid-oriented fully functional 3D fracture simulator with shear decoupling. An example for each respective case is presented in this paper. In the first example, in which high PZS was considered to be the dominant reason for screenout or pressure out, the well was restimulated successfully by implementing the solutions presented in this paper. In the second example, in which high PDL was considered to be the main reason for screenout, there were several wells in the same project area that exhibited the same behavior resulting in screenouts. After implementing the solutions presented in this paper to address high PDL, all new wells were stimulated successfully without any issues.

Ramurthy, M.; Lyons, B.; Hendrickson, R.B.; Barree, R.D.; Magill, D.R. [Halliburton, Denver, CO (United States)

2009-08-15T23:59:59.000Z

265

Spectroscopic study of a long high-electron-density argon plasma column generated at atmospheric pressure  

SciTech Connect (OSTI)

A stable plasma column is generated in a quartz tube using a pair of hollow electrodes driven by a sinusoidal power supply of 45 kHz at atmospheric pressure in argon. Two distinct operating modes (low-current and high-current modes) are identified through observing its discharge phenomena, measuring its electrical characteristics, and determining the gas temperatures by spectroscopic diagnosis of Q branch of UV OH spectrum. The electron density in the high-current mode is diagnosed by Stark broadening and is found to be two orders higher than that in low-current mode.

Li Shouzhe; Huang Wentong; Wang Dezhen [Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, and School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116023 (China)

2010-02-15T23:59:59.000Z

266

High Sensitivity Combined with Extended Structural Coverage of Labile Compounds via Nanoelectrospray Ionization at Subambient Pressures  

SciTech Connect (OSTI)

Subambient pressure ionization with nanoelectrospray (SPIN) has proven to be effective in producing ions with high efficiency and transmitting them to low pressures for high sensitivity mass spectrometry (MS) analysis. Here we present evidence that not only does the SPIN source improve MS sensitivity but also allows for gentler ionization conditions. The gentleness of a conventional heated capillary electrospray ionization (ESI) source and the SPIN source was compared by the liquid chromatography mass spectrometry (LC-MS) analysis of colominic acid. Colominic acid is a mixture of sialic acid polymers of different lengths containing labile glycosidic linkages between monomer units necessitating a gentle ion source. By coupling the SPIN source with high resolution mass spectrometry and using advanced data processing tools, we demonstrate much extended coverage of sialic acid polymer chains as compared to using the conventional ESI source. Additionally we show that SPIN-LC-MS is effective in elucidating polymer features with high efficiency and high sensitivity previously unattainable by the conventional ESI-LC-MS methods. ?

Cox, Jonathan T.; Kronewitter, Scott R.; Shukla, Anil K.; Moore, Ronald J.; Smith, Richard D.; Tang, Keqi

2014-10-07T23:59:59.000Z

267

High pressure/high temperature hydrogen permeability in candidate stirling engine alloys  

Science Journals Connector (OSTI)

Hydrogen permeation tests of eight high-temperature engineering alloys were conducted in 20.7 MPa hydrogen at 923 to 1088 K for assessing suitability in Stirling engine application for heater head and heater head...

S. Bhattacharyya; E. J. Vesely; V. L. Hill

1982-03-01T23:59:59.000Z

268

High-Pressure Core Structures of Si Nanoparticles for Solar Energy Conversion  

Science Journals Connector (OSTI)

We present density functional and many body perturbation theory calculations of the electronic, optical, and impact ionization properties of Si nanoparticles (NPs) with core structures based on high-pressure bulk Si phases. Si particles with a BC8 core structure exhibit significantly lower optical gaps and multiple exciton generation (MEG) thresholds, and an order of magnitude higher MEG rate than diamondlike ones of the same size. Several mechanisms are discussed to further reduce the gap, including surface reconstruction and chemistry, excitonic effects, and embedding pressure. Experiments reported the formation of BC8 NPs embedded in amorphous Si and in amorphous regions of femtosecond-laser doped “black silicon.” For all these reasons, BC8 nanoparticles may be promising candidates for MEG-based solar energy conversion.

S. Wippermann; M. Vörös; D. Rocca; A. Gali; G. Zimanyi; G. Galli

2013-01-24T23:59:59.000Z

269

Materials issues in high temperature ultrasonic transducers for under-sodium viewing  

SciTech Connect (OSTI)

Liquid sodium is used as the coolant in some fast spectrum nuclear reactors. This material is optically opaque. To facilitate operations and maintenance activities, an ultrasonic under-sodium viewing system has been developed. In the USA, the technology was successfully demonstrated in the 1970s and, over the intervening 30+ years, the capability was lost. This paper reports materials challenges encountered in developing both single-element and linear phased-array 2-MHz transducers that must operate at temperatures up to 260 deg. C. The critical issues are fundamentally material selection: the ability of a transducer to be immersed into liquid sodium and function at 260 deg. C, to achieve wetting and transmission of ultrasound into the sodium, and to be able to be removed and re-used.

Bond, L. J.; Griffin, J. W.; Posakony, G. J.; Harris, R. V.; Baldwin, D. L. [Pacific Northwest National Laboratory, Richland, WA 99354 (United States)

2012-05-17T23:59:59.000Z

270

Ground-state properties and high-pressure behavior of plutonium dioxide: Density functional theory calculations  

Science Journals Connector (OSTI)

Plutonium dioxide is of high technological importance in nuclear fuel cycle and is particularly crucial in long-term storage of Pu-based radioactive waste. Using first-principles density-functional theory, in this paper we systematically study the structural, electronic, mechanical, thermodynamic properties, and pressure-induced structural transition of PuO2. To properly describe the strong correlation in Pu?5f electrons, the local-density approximation (LDA)+U and the generalized gradient approximation+U theoretical formalisms have been employed. We optimize U parameter in calculating the total energy, lattice parameters, and bulk modulus at nonmagnetic, ferromagnetic, and antiferromagnetic configurations for both ground-state fluorite structure and high-pressure cotunnite structure. Best agreement with experiments is obtained by tuning the effective Hubbard parameter U at around 4 eV within LDA+U approach. After carefully testing the validity of the ground-state calculation, we further investigate the bonding nature, elastic constants, various moduli, Debye temperature, hardness, ideal tensile strength, and phonon dispersion for fluorite PuO2. Some thermodynamic properties, e.g., Gibbs free energy, volume thermal expansion, and specific heat are also calculated. As for cotunnite phase, besides elastic constants, various moduli, and Debye temperature at 0 GPa, we have further presented our calculated electronic, structural, and magnetic properties for PuO2 under pressure up to 280 GPa. A metallic transition at around 133 GPa and an isostructural transition in pressure range of 75–133 GPa are predicted. Additionally, as an illustration on the valency trend and subsequent effect on the mechanical properties, the calculated results for other actinide metal dioxides (ThO2, UO2, and NpO2) are also presented.

Ping Zhang; Bao-Tian Wang; Xian-Geng Zhao

2010-10-19T23:59:59.000Z

271

Simplified configuration for the combustor of an oil burner using a low pressure, high flow air-atomizing nozzle  

DOE Patents [OSTI]

The invention relates to clean burning of fuel oil with air. More specifically, to a fuel burning combustion head using a low-pressure, high air flow atomizing nozzle so that there will be a complete combustion of oil resulting in a minimum emission of pollutants. The improved fuel burner uses a low pressure air atomizing nozzle that does not result in the use of additional compressors or the introduction of pressurized gases downstream, nor does it require a complex design. Inventors:

Butcher, Thomas A. (Port Jefferson, NY); Celebi, Yusuf (Middle Island, NY); Fisher, Leonard (Colrain, MA)

2000-09-15T23:59:59.000Z

272

Trace element partitioning between baddeleyite and carbonatite melt at high pressures and high temperatures  

E-Print Network [OSTI]

as the heavy rare earth elements (HREE) prefer to enter baddeleyite rather than carbonate melts (D>1), whereas the light rare earth elements (LREE) and other trace elements behave incompatibly (D in carbonatite melts. Baddeleyite is known to accumulate the high field strength elements (HFSE) and some rare

273

Participant characteristics and intervention processes associated with reductions in television viewing in the High Five for Kids study  

Science Journals Connector (OSTI)

AbstractObjective To evaluate the High Five for Kids intervention effect on television within subgroups, examine participant characteristics associated with process measures and assess perceived helpfulness of television intervention components. Method High Five (randomized controlled trial of 445 overweight/obese 2–7 year-olds in Massachusetts [2006–2008]) reduced television by 0.36 h/day. 1-year effects on television viewing, stratified by subgroup, were assessed using linear regression. Among intervention participants (n = 253), associations of intervention component helpfulness with television reduction were examined using linear regression and associations of participant characteristics with processes linked to television reduction (choosing television and completing intervention visits) were examined using logistic regression. Results High Five reduced television across subgroups. Parents of Latino (versus white) children had lower odds of completing ? 2 study visits (Odds Ratio: 0.39 [95% Confidence Interval: 0.18, 0.84]). Parents of black (versus white) children had higher odds of choosing television (Odds Ratio: 2.23 [95% Confidence Interval: 1.08, 4.59]), as did parents of obese (versus overweight) children and children watching ? 2 h/day (versus < 2) at baseline. Greater perceived helpfulness was associated with greater television reduction. Conclusion Clinic-based motivational interviewing reduces television viewing in children. Low cost education approaches (e.g., printed materials) may be well-received. Parents of children at higher obesity risk could be more motivated to reduce television.

Elizabeth M. Cespedes; Christine M. Horan; Matthew W. Gillman; Steven L. Gortmaker; Sarah Price; Sheryl L. Rifas-Shiman; Kathleen Mitchell; Elsie M. Taveras

2014-01-01T23:59:59.000Z

274

Influence of Intense Beam in High Pressure Hydrogen Gas Filled RF Cavities  

SciTech Connect (OSTI)

The influence of an intense beam in a high-pressure gas filled RF cavity has been measured by using a 400 MeV proton beam in the Mucool Test Area at Fermilab. The ionization process generates dense plasma in the cavity and the resultant power loss to the plasma is determined by measuring the cavity voltage on a sampling oscilloscope. The energy loss has been observed with various peak RF field gradients (E), gas pressures (p), and beam intensities in nitrogen and hydrogen gases. Observed RF energy dissipation in single electron (dw) in N{sub 2} and H{sub 2} gases was 2 10{sup -17} and 3 10{sup -17} Joules/RF cycle at E/p = 8 V/cm/Torr, respectively. More detailed dw measurement have been done in H{sub 2} gas at three different gas pressures. There is a clear discrepancy between the observed dw and analytical one. The discrepancy may be due to the gas density effect that has already been observed in various experiments.

Yonehara, K.; Chung, M.; Collura, M.G.; Jana, M.R.; Leonova, M.; Moretti, A.; Popovic, M.; Schwarz, T.; Tollestrup, A.; /Fermilab; Johnson, R.P.; Franagan, G.; /Muons, Inc. /IIT

2012-05-01T23:59:59.000Z

275

Spectroscopic diagnostics of a pulsed discharge in high-pressure argon  

SciTech Connect (OSTI)

Results of investigation of high-pressure argon plasma excited by a high-current pulsed volume discharge are presented. The plasma diagnostics employs spatiotemporal dependences of the emission intensity in the VUV - visible range. A homogenous discharge is observed at pressures up to 10 atm. It is found that the spectrum of the UV - visible photorecombination continuum is sensitive to the discharge constriction. Change in the shape of the spectrum is caused bythe change of the type of positive charge carriers upon passing of the discharge from the uniform phase (molecular Ar{sub 2}{sup +} ions) to the arc phase (atomic Ar{sup +} ions). Experimental data and model calculations show that the electron heating after the main excitation pulse is a highly undesirable process. It slows down the recombination flow in the plasma, which results in stretching of all the kinetic processes for all excited components in time, and hence in a decrease in the peak values of their concentrations. Electron collision-induced mixing effi-ciently converts the reservoir of long-lived Ar{sub 2}* molecules in the triplet state into rapidly emitting singlet excimers. It is this mechanism that dominates the production of singlet Ar{sub 2}* excimer molecules. The threshold concentration needed to obtain lasing at a wavelength of 127 nm on Ar{sub 2}* excimers ({sup 1{Sigma}+}{sub u(v=0)}) was, according to calculations, about 5x10{sup 15} cm{sup -3} for the gain 0.05 cm{sup -1}. This concentration can be achieved in the case of homogeneous pulsed discharge pumping with the peak electron concentration 2.x10{sup 16} cm{sup -3} at the argon pressure 10 atm.

Treshchalov, A B; Lissovskii, A A [Institute of Physics, University of Tartu, Tartu (Estonia)

2010-05-26T23:59:59.000Z

276

Small-angle neutron scattering study of high-pressure sintered detonation nanodiamonds  

SciTech Connect (OSTI)

The structure of detonation diamonds sintered at a high pressure (7 GPa) and temperatures of 1200-1700 Degree-Sign C has been investigated by small-angle neutron scattering. It is shown that sintering leads to an increase in the particle size from 6 to 30 nm and established that this increase is due to the chainlike oriented attachment of particles. This study supplements the oriented-attachment model, which was suggested based on the X-ray diffraction spectra of detonation nanodiamonds (DNDs) sintered under the same conditions.

Kidalov, S. V.; Shakhov, F. M., E-mail: fedor.shakhov@mail.ioffe.ru [Ioffe Physical-Technical Institute of the Russian Academy of Sciences (Russian Federation); Lebedev, V. T.; Orlova, D. N.; Grushko, Yu. S. [Russian Academy of Sciences, Konstantinov St. Petersburg Nuclear Physics Institute (Russian Federation)

2011-12-15T23:59:59.000Z

277

Liquid dispersion and holdup in a small-scale upflow hydrotreater at high temperatures and pressure  

Science Journals Connector (OSTI)

Residence time distribution experiments were carried out at high temperatures and pressure in a small-scale upflow reactor. A diluted and a non-diluted bed were tested. Middle distillates and hydrogen were used as feeds. The axial dispersion model was used to describe the liquid flow through the packed bed. The dependency of Pe and liquid holdup on feed velocity and temperature was examined. The behaviour of the beds tested at hot flow conditions is compared with that of identical beds tested at ambient conditions using toluene as liquid feed and the effect of liquid-phase properties is discussed.

A.M. Thanos; P.A. Galtier; N.G. Papayannakos

2001-01-01T23:59:59.000Z

278

Low loss hollow optical-waveguide connection from atmospheric pressure to ultra-high vacuum  

SciTech Connect (OSTI)

A technique for optically accessing ultra-high vacuum environments, via a photonic-crystal fiber with a long small hollow core, is described. The small core and the long bore enable a pressure ratio of over 10{sup 8} to be maintained between two environments, while permitting efficient and unimpeded delivery of light, including ultrashort optical pulses. This delivery can be either passive or can encompass nonlinear optical processes such as optical pulse compression, deep UV generation, supercontinuum generation, or other useful phenomena.

Ermolov, A.; Mak, K. F.; Tani, F.; Hölzer, P.; Travers, J. C. [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany)] [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany); Russell, P. St. J. [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany) [Max Planck Institute for the Science of Light, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany); Department of Physics, University of Erlangen-Nuremberg, Günther-Scharowsky-Str. 1, 91058 Erlangen (Germany)

2013-12-23T23:59:59.000Z

279

Highly Robust Thin-Film Composite Pressure Retarded Osmosis (PRO) Hollow Fiber Membranes with High Power Densities for Renewable Salinity-Gradient Energy Generation  

Science Journals Connector (OSTI)

(1) Salinity-gradient energy (i.e., osmotic power) generated from the mixing of solutions with different salinities via pressure retarded osmosis (PRO) represents a high potential source of renewable energy. ... Thorsen, T.; Holt, T.The potential for power production from salinity gradients by pressure retarded osmosis J. Membr. ... When using saline water as the feed soln., the efficiency of the osmotic pressure decreases with increasing feed concn. ...

Gang Han; Peng Wang; Tai-Shung Chung

2013-06-17T23:59:59.000Z

280

High-Frequency Coherent Edge Fluctuations in a High-Pedestal-Pressure Quiescent H-Mode Plasma  

Science Journals Connector (OSTI)

A set of high frequency coherent (HFC) modes (f=80–250??kHz) is observed with beam emission spectroscopy measurements of density fluctuations in the pedestal of a strongly shaped quiescent H-mode plasma on DIII-D, with characteristics predicted for kinetic ballooning modes (KBM): propagation in the ion-diamagnetic drift direction; a frequency near 0.2–0.3 times the ion-diamagnetic frequency; inferred toroidal mode numbers of n?10–25; poloidal wave numbers of k??0.17–0.4??cm-1; and high measured decorrelation rates (?c-1??s?0.5×106??s-1). Their appearance correlates with saturation of the pedestal pressure.

Z. Yan; G. R. McKee; R. J. Groebner; P. B. Snyder; T. H. Osborne; K. H. Burrell

2011-07-29T23:59:59.000Z

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


281

High pressure test results of a catalytic combustor for gas turbine  

SciTech Connect (OSTI)

Recently, the use of gas turbine systems, such as combined cycle and cogeneration systems, has gradually increased in the world. But even when a clean fuel such as LNG (liquefied natural gas) is used, thermal NO{sub x} is generated in the high temperature gas turbine combustion process. The NO{sub x} emission from gas turbines is controlled through selective catalytic reduction processes (SCR) in the Japanese electric industry. If catalytic combustion could be applied to the combustor of the gas turbine, it is expected to lower NO{sub x} emission more economically. Under such high temperature and high pressure conditions, as in the gas turbine, however, the durability of the catalyst is still insufficient. So it prevents the realization of a high temperature catalytic combustor. To overcome this difficulty, a catalytic combustor combined with premixed combustion for a 1,300 C class gas turbine was developed. In this method, catalyst temperature is kept below 1,000 C, and a lean premixed gas is injected into the catalytic combustion gas. As a result, the load on the catalyst is reduced and it is possible to prevent the catalyst deactivation. After a preliminary atmospheric test, the design of the combustion was modified and a high pressure combustion test was conducted. As a result, it was confirmed that NO{sub x} emission was below 10 ppm (at 16 percent O{sub 2}) at a combustor outlet gas temperature of 1,300 C and that the combustion efficiency was almost 100%. This paper presents the design features and test results of the combustor.

Fujii, T.; Ozawa, Y.; Kikumoto, S.; Sato, M. [Central Research Inst. of Electric Power Industry, Yokosuka, Kanagawa (Japan); Yuasa, Y.; Inoue, H. [Kansai Electric Power Co., Inc., Amagasaki, Hyogo (Japan)

1998-07-01T23:59:59.000Z

282

Focused excimer laser initiated, radio frequency sustained high pressure air plasmas  

SciTech Connect (OSTI)

Measurements and analysis of air breakdown processes and plasma production by focusing 193 nm, 300 mJ, 15 MW high power laser radiation inside a 6 cm diameter helical radio frequency (RF) coil are presented. Quantum resonant multi-photon ionization (REMPI) and collisional cascade laser ionization processes are exploited that have been shown to produce high-density (n{sub e} {approx} 7 x 10{sup 16}/cm{sup 3}) cylindrical seed plasmas at 760 Torr. Air breakdown in lower pressures (from 7-22 Torr), where REMPI is the dominant laser ionization process, is investigated using an UV 18 cm focal length lens, resulting in a laser flux of 5.5 GW/cm{sup 2} at the focal spot. The focused laser power absorption and associated shock wave produce seed plasmas for sustainment by the RF (5 kW incident power, 1.5 s) pulse. Measurements of the helical RF antenna load impedance in the inductive and capacitive coupling regimes are obtained by measuring the loaded antenna reflection coefficient. A 105 GHz interferometer is used to measure the plasma electron density and collision frequency. Spectroscopic measurements of the plasma and comparison with the SPECAIR code are made to determine translational, rotational, and vibrational neutral temperatures and the associated neutral gas temperature. From this and the associated measurement of the gas pressure the electron temperature is obtained. Experiments show that the laser-formed seed plasma allows RF sustainment at higher initial air pressures (up to 22 Torr) than that obtained via RF-only initiation (<18 Torr) by means of a 0.3 J UV laser pulse.

Giar, Ryan; Scharer, John [Department of Electrical Engineering, University of Wisconsin-Madison, 506 Engineering Research Building, 1500 Engineering Drive, Madison, Wisconsin 53706 (United States)

2011-11-15T23:59:59.000Z

283

High-pressure coal fuel processor development. Task 1, Proof of principle testing  

SciTech Connect (OSTI)

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.

Greenhalgh, M.L.

1992-11-01T23:59:59.000Z

284

Reevaluation of Type I Diamonds for Infrared and Raman Spectroscopy in High-Pressure Diamond Anvil Cells  

Science Journals Connector (OSTI)

Types Ia, IIa, and IIb diamonds have been compared for their use as anvils in infrared and Raman high-pressure spectroscopy. In the mid-infrared region above 2700 cm?1,...

Wong, P T T; Klug, D D

1983-01-01T23:59:59.000Z

285

Influence of energy contributions to a high-voltage atmospheric-pressure discharge on the efficiency of conversion of ethanol  

Science Journals Connector (OSTI)

The results of experimental investigations of the conversion of ethanol in a high-voltage atmospheric-pressure discharge have been presented. The influence of the energy parameters of the discharge on the yield a...

S. A. Zhdanok; A. V. Krauklis; P. P. Samtsov…

2006-11-01T23:59:59.000Z

286

A high-pressure polymorph of chlorpropamide formed on hydrostatic compression of the -form in saturated ethanol solution  

Science Journals Connector (OSTI)

The crystal structure of a high-pressure monoclinic polymorph (P2111) of chlorpropamide has been determined. It is formed at 2.8 GPa on hydrostatic compression of the orthorhombic stable -polymorph (P212121) in saturated ethanol solution.

Seryotkin, Y.V.

2013-01-19T23:59:59.000Z

287

A compact bellows-driven diamond anvil cell for high-pressure, low-temperature magnetic measurements  

SciTech Connect (OSTI)

We present the design of an efficient bellows-controlled diamond anvil cell that is optimized for use inside the bores of high-field superconducting magnets in helium-3 cryostats, dilution refrigerators, and commercial physical property measurement systems. Design of this non-magnetic pressure cell focuses on in situ pressure tuning and measurement by means of a helium-filled bellows actuator and fiber-coupled ruby fluorescence spectroscopy, respectively. We demonstrate the utility of this pressure cell with ac susceptibility measurements of superconducting, ferromagnetic, and antiferromagnetic phase transitions to pressures exceeding 8 GPa. This cell provides an opportunity to probe charge and magnetic order continuously and with high resolution in the three-dimensional Magnetic Field–Pressure–Temperature parameter space.

Feng, Yejun [The Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States) [The Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637 (United States); Silevitch, D. M.; Rosenbaum, T. F. [The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637 (United States)] [The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637 (United States)

2014-03-15T23:59:59.000Z

288

Highly efficient inverted top emitting organic light emitting diodes using a transparent top electrode with color stability on viewing angle  

SciTech Connect (OSTI)

We report a highly efficient phosphorescent green inverted top emitting organic light emitting diode with excellent color stability by using the 1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile/indium zinc oxide top electrode and bis(2-phenylpyridine)iridium(III) acetylacetonate as the emitter in an exciplex forming co-host system. The device shows a high external quantum efficiency of 23.4% at 1000?cd/m{sup 2} corresponding to a current efficiency of 110?cd/A, low efficiency roll-off with 21% at 10?000?cd/m{sup 2} and low turn on voltage of 2.4?V. Especially, the device showed very small color change with the variation of ?x?=?0.02, ?y?=?0.02 in the CIE 1931 coordinates as the viewing angle changes from 0° to 60°. The performance of the device is superior to that of the metal/metal cavity structured device.

Kim, Jung-Bum; Lee, Jeong-Hwan; Moon, Chang-Ki; Kim, Jang-Joo, E-mail: jjkim@snu.ac.kr [Department of Materials Science and Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of)

2014-02-17T23:59:59.000Z

289

XANES of high-pressure Kr clusters in Be and Si  

Science Journals Connector (OSTI)

We report on the experimental investigation of high-pressure Kr clusters in Be and Si single crystals by x-ray absorption near-edge spectroscopy. The samples, obtained by ion implantation, were investigated for several temperatures in the range 83–670 K. We show that the near-edge structure of the absorption spectra is sufficient to obtain valuable quantitative information concerning the contracted lattice parameter of the solid rare gas agglomerates, depending on the overpressure exerted on the clusters by the host matrix. Our data compare to the extended x-ray absorption fine structure (EXAFS) experimental spectra on solid Kr at 4.2 K, and at 300 K under high pressure. Furthermore, in order to check the consistency of our experimental data with EXAFS results taken from the literature, we performed theoretical simulations using the FEFF6 code. These calculations showed good agreement with both sets of data and confirmed our experimental conclusions, permitting the evaluation of the lattice contraction, average coordination, and size of the cluster ensemble.

Giuseppe Faraci; Agata R. Pennisi; Jean-Louis Hazemann

1997-11-15T23:59:59.000Z

290

High pressure test results of a catalytically assisted ceramic combustor for a gas turbine  

SciTech Connect (OSTI)

A catalytically assisted ceramic combustor for a gas turbine was designed to achieve low NOx emission under 5 ppm at a combustor outlet temperature over 1300 C. This combustor is composed of a burner system and a ceramic liner behind the burner system. The burner system consist of 6 catalytic combustor segments and 6 premixing nozzles, which are arranged in parallel and alternately. The ceramic liner is made up of the layer of outer metal wall, ceramic fiber, and inner ceramic tiles. Fuel flow rates for the catalysts and the premixing nozzles are controlled independently. Catalytic combustion temperature is controlled under 1000 C, premixed gas is injected from the premixing nozzles to the catalytic combustion gas and lean premixed combustion over 1300 C is carried out in the ceramic liner. This system was designed to avoid catalytic deactivation at high temperature and thermal and mechanical shock fracture of the honeycomb monolith of catalyst. A combustor for a 10 MW class, multican type gas turbine was tested under high pressure conditions using LNG fuel. Measurements of emission, temperature, etc. were made to evaluate combustor performance under various combustion temperatures and pressures. This paper presents the design features and the test results of this combustor.

Ozawa, Y.; Tochihara, Y.; Mori, N.; Yuri, I. [Central Research Inst. of Electric Power Industry, Yokosuka, Kanagawa (Japan); Kanazawa, T.; Sagimori, K. [Kansai Electric Power Co., Inc., Amagasaki, Hyogo (Japan)

1999-07-01T23:59:59.000Z

291

Theory of the reentrant quantum rotational phase transition in high-pressure HD  

Science Journals Connector (OSTI)

The phase diagram of HD near 50 GPa exhibits a reentrant phase transition where a rotationally ordered (“broken symmetry”) crystalline phase surprisingly transforms into a rotationally “disordered” high-symmetry phase upon cooling. The qualitative reason for reentrance is the higher entropy of the broken symmetry phase, due to the inequivalence of H and D, as opposed to the low entropy of the high-symmetry phase where the rotational melting is quantum mechanical—a Pomeranchuk-like mechanism. Aiming at a quantitative understanding of this system, we present path integral Monte Carlo (MC) constant-pressure calculations for HD based on empirical but very realistic intermolecular interactions. Ignoring quantum mechanics at first, we use a metadynamics-based classical MC method to seek the lowest-energy zero-temperature classical state, which we identify as a very similar hcp-based structure C2/c as hypothesized by Surh et al. [Phys. Rev. B 55, 11330 (1997)]. Upon turning quantum rotational effects on, we calculate the pressure-temperature phase diagram by monitoring a lattice biased order parameter, and find a reentrant phase boundary in good agreement with experiment. The entropy jump across the transition is found to be comparable with ln2, the value expected for a Pomeranchuk mechanism. A comparison with earlier studies is also presented, yielding relevant information about the role of factors that quantitatively determine the reentrant part of the phase diagram.

Yanier Crespo; Alessandro Laio; Giuseppe E. Santoro; Erio Tosatti

2011-10-28T23:59:59.000Z

292

High-Throughput Thin Film Approach for Screening of Temperature-Pressure-Composition Phase Space  

SciTech Connect (OSTI)

Many solar energy technologies, for example CIGS and CdTe photovoltaics, utilize materials in thin film form. The equilibrium phase diagrams for these and other more novel solar energy materials are not known or are irrelevant because of the non-equilibrium character of the thin film growth processes. We demonstrate a high-throughput thin film approach for screening of temperature-pressure-composition phase diagrams and phase spaces. The examples in focus are novel solar absorbers Cu-N, Cu-O and p-type transparent conductors in the Cr2O3-MnO system. The composition axis of the Cr2O3-MnO phase diagram was screened using a composition spread method. The temperature axis of the Mn-O phase diagram was screened using a temperature spread method. The pressure axes of the Cu-N and Cu-O phase diagrams were screened using rate spread method with the aid of non-equilibrium growth phenomena. Overall these three methods constitute an approach to high-throughput screening of inorganic thin film phase diagrams. This research is supported by U.S. Department of Energy as a part of two NextGen Sunshot projects and an Energy Frontier Research Center.

Zakutayev, A.; Subramaniyan, A.; Caskey, C. M.; Ndione, P. F.; Richards, R. M.; O'Hayre, R.; Ginley, D. S.

2013-01-01T23:59:59.000Z

293

Effects of attenuation, dispersion, and high sound?pressure levels on acoustic wave distortion in horns  

Science Journals Connector (OSTI)

High?power sound sources have received a lot of attention in the past few years due to renewed interest in industrial applications of high?intensity sounds such as the acoustic agglomeration of aerosols or combustion enhancement. Most high?power sound sources require a horn to match the source impedance to the medium where the sound is radiated. Such horns introduce distortion in the initial waveform which can be detrimental to the agglomeration or combustion enhancement process. Boundary?layer attenuation smooths the wave shape while dispersion breaks up the symmetry of the waveform. Horn?induced dispersion is usually the dominant dispersion mechanism resulting in strong peaks in the waveform. Finally due to the very high acoustic levels at the horn throat finite?amplitude effects are responsible for a significant amount of distortion at high frequencies. Simple examples of waveform distortion due to these various mechanisms are shown. The effects of sound?pressure level horn design and frequency on distortion are illustrated for an exponential horn and several initial wave shapes. Experimental results are presented that compare very well with theory.

Frederic G. Pla; Gerhard Reethof

1988-01-01T23:59:59.000Z

294

Engineering development of a lightweight high-pressure scarifier for tank waste retrieval  

SciTech Connect (OSTI)

The Retrieval Process Development and Enhancements Program (RPD&E) is sponsored by the U.S. Department of Energy Tanks Focus Area to investigate existing and emerging retrieval processes suitable for the retrieval of high-level radioactive waste inside underground storage tanks. This program, represented by industry, national laboratories, and academia, seeks to provide a technical and cost basis to support site-remediation decisions. Part of this program has involved the development of a high-pressure waterjet dislodging system and pneumatic conveyance integrated as a scarifier. Industry has used high-pressure waterjet technology for many years to mine, cut, clean, and scarify materials with a broad range of properties. The scarifier was developed as an alternate means of retrieving waste inside Hanford single-shell tanks, particularly hard, stubborn waste. Testing of the scarifier has verified its ability to retrieve a wide range of tank waste ranging from extremely hard waste that is resistant to other dislodging means to soft sludge and even supernatant fluid. Since the scarifier expends water at a low rate and recovers most of the water as it is used, the scarifier is well suited for retrieval of tanks that leak and cannot be safely sluiced or applications where significant waste dilution is not acceptable. Although the original scarifier was effective, it became evident that a lighter, more compact version that would be compatible with light weight deployment systems under development, such as the Light Duty Utility Arm, was needed. At the end of FY 95, the Light Weight Scarifier (LWS) was designed to incorporate the features of the original scarifier in a smaller, lighter end effector. During FY 96, the detailed design of the LWS was completed and two prototypes were fabricated.

Hatchell, B.K.

1997-09-01T23:59:59.000Z

295

Room-Temperature Silicon Nitrides Prepared with Very High Rates (>50 nm/s) in Atmospheric-Pressure Very High-Frequency Plasma  

Science Journals Connector (OSTI)

We have investigated the structure and stability of SiN x ...films deposited with very high rates (>50 nm/s) in atmospheric-pressure (AP) He-based plasma excited by a 150 MHz ver...

Hiroaki Kakiuchi; Hiromasa Ohmi; Kei Nakamura…

2010-10-01T23:59:59.000Z

296

A HIGH RESOLUTION VIEW OF THE WARM ABSORBER IN THE QUASAR MR 2251-178  

SciTech Connect (OSTI)

High resolution X-ray spectroscopy of the warm absorber in a nearby quasar, MR 2251-178 (z = 0.06398), is presented. The observations were carried out in 2011 using the Chandra High Energy Transmission Grating (HETG) and the XMM-Newton Reflection Grating Spectrometer, with net exposure times of approximately 400 ks each. A multitude of absorption lines from C to Fe are detected, revealing at least three warm absorbing components ranging in ionization parameter from log (?/erg cm s{sup –1}) = 1-3 with outflow velocities ?< 500 km s{sup –1}. The lowest ionization absorber appears to vary between the Chandra and XMM-Newton observations, which implies a radial distance of between 9 and 17 pc from the black hole. Several broad soft X-ray emission lines are strongly detected, most notably from He-like oxygen, with FWHM velocity widths of up to 10,000 km s{sup –1}, consistent with an origin from broad-line region (BLR) clouds. In addition to the warm absorber, gas partially covering the line of sight to the quasar appears to be present, with a typical column density of N{sub H} = 10{sup 23} cm{sup –2}. We suggest that the partial covering absorber may arise from the same BLR clouds responsible for the broad soft X-ray emission lines. Finally, the presence of a highly ionized outflow in the iron K band from both the 2002 and 2011 Chandra HETG observations appears to be confirmed, which has an outflow velocity of –15600 ± 2400 km s{sup –1}. However, a partial covering origin for the iron K absorption cannot be excluded, resulting from low ionization material with little or no outflow velocity.

Reeves, J. N.; Gofford, J.; Nardini, E. [Astrophysics Group, School of Physical and Geographical Sciences, Keele University, Keele, Staffordshire, ST5 5BG (United Kingdom); Porquet, D. [Observatoire Astronomique de Strasbourg, Université de Strasbourg, CNRS, UMR 7550, 11 rue de l'Université, F-67000 Strasbourg (France); Braito, V. [INAF - Osservatorio Astronomico di Brera, Via Bianchi 46 I-23807 Merate (Italy); Turner, T. J. [Center for Space Science and Technology, University of Maryland Baltimore County, 1000 Hilltop Circle, Baltimore, MD 21250 (United States); Crenshaw, D. M. [Department of Physics and Astronomy, Georgia State University, Astronomy Offices, One Park Place South SE, Suite 700, Atlanta, GA 30303 (United States); Kraemer, S. B., E-mail: j.n.reeves@keele.ac.uk [Institute for Astrophysics and Computational Sciences, Department of Physics, The Catholic University of America, Washington, DC 20064 (United States)

2013-10-20T23:59:59.000Z

297

Application of LBB to high energy pipings of a pressurized water reactor in Korea  

Science Journals Connector (OSTI)

The application of the leak before break (LBB) technology to the newly constructed pressurized water reactors (PWRs) has been approved in Korea for several high energy systems that can meet rigorous acceptance criteria. The LBB application in Korea is based on the US Nuclear Regulatory Commision (USNRC) requirements. The purpose of the LBB evaluation is to eliminate the dynamic effects associated with the postulated double-ended guillotine break (DEGB) from design basis loads, as well as to eliminate pipe whip restraints and jet impingement barriers. There were several issues on the application of LBB to the primary coolant loop and the pressurizer surge line. Of concern were the material properties for the carbon steel for the primary coolant loop, estimation of the crack opening area at the pipe-to-nozzle interface considering the asymmetry, and the leakage crack size which barely meets the required margin of 2 for the surge line, etc. Some additional work was required by the safety authority to maintain the global safety of the plant at a sufficient level. This paper describes the regulatory application of LBB in Korea, and the issues encountered during the regulatory review.

Jeong-Bae Lee; Young Hwan Choi

1999-01-01T23:59:59.000Z

298

The deterioration in heat transfer to fluids at supercritical pressure and high heat fluxes  

E-Print Network [OSTI]

At slightly supercritical pressure and in the neighborhood of the pseudo-critical temperature (defined as the temperature corresponding to the peak in specific heat at the operating pressure), the heat transfer coefficient ...

Shiralkar, B. S.

1968-01-01T23:59:59.000Z

299

Equations of state and phase transformation of depleted uranium DU-238 by high pressure-temperature diffraction studies  

Science Journals Connector (OSTI)

We have conducted in situ high-pressure diffraction experiments on depleted uranium (DU-238) at pressures up to 8.5GPa and temperatures up to 1123K. From the pressure (P)-volume (V)-temperature (T) measurements, thermoelastic parameters were derived for ?-uranium based on a modified high-T Birch-Murnaghan equation of state and a thermal-pressure approach. With the pressure derivative of the bulk modulus K0? fixed at 4.0, we obtained ambient bulk modulus K0=117(2)GPa, temperature derivative of bulk modulus at constant pressure (?K??T)P=?3.4(4)×10?2GPa?K and at constant volume (?K??T)v=?1.1(6)×10?2GPa?K, volumetric thermal expansivity ?T=a+bT, with a=1.2(±0.4)×10?5K?1 and b=8.0(±0.7)×10?8K?2, and the pressure derivative of thermal expansion (????P)T=?2.5(5)×10?6GPa?1K?1. Within the experimental errors, the ambient bulk modulus and volumetric thermal expansion derived from this work are in good agreement with previous experimental results, whereas all other thermoelastic parameters represent the first determinations for the ? phase of uranium. We also studied the ?-? phase transformation and obtained a phase boundary described by T (inK)=1032+7.4P(inGPa). Although the ?-phase uranium cannot be pressure quenched to ambient conditions, it was observed to be stable upon cooling from 1123to300K at pressures of 7–8GPa. These observations indicate that pressure, in addition to the commonly utilized alloying techniques, provides an alternative route for stabilizing the ?-uranium at room temperature.

Yusheng Zhao; Jianzhong Zhang; Donald W. Brown; Deniece R. Korzekwa; Robert S. Hixson; Liping Wang

2007-05-11T23:59:59.000Z

300

Lessons Learned from Practical Field Experience with High Pressure Gaseous Fuels  

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

5/2010 5/2010 www.cleanvehicle.org 1 Lessons Learned from Practical Field Experience with High Pressure Gaseous Fuels DOE - DOT CNG - H 2 Workshop December 10, 2009 Douglas Horne, PE - CVEF President Rob Adams, P.Eng. - Marathon Technical Services The Facts  NGVs have been used in North America for over 30 years  Codes and Standards (C&S) provide opportunity for safe reliable operation of NGVs  C&S evolve with new technology and field experience  People make mistakes, continuous training is critical for safe operations  Cylinders have a limited life -track your cylinders! 2/25/2010 www.cleanvehicle.org 2 Incidents in North America  Since 1984 CVEF has recorded 97 incidents of which 67 involved CNG vehicles - 37 incidents involve either a CNG leak (15) or a

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


301

Dynamics of multiple double layers in high pressure glow discharge in a simple torus  

SciTech Connect (OSTI)

Parametric characterization of multiple double layers is done during high pressure glow discharge in a toroidal vessel of small aspect ratio. Although glow discharge (without magnetic field) is known to be independent of device geometry, but the toroidal boundary conditions are conducive to plasma growth and eventually the plasma occupy the toroidal volume partially. At higher anode potential, the visibly glowing spots on the body of spatially extended anode transform into multiple intensely luminous spherical plasma blob structures attached to the tip of the positive electrode. Dynamics of multiple double layers are observed in argon glow discharge plasma in presence of toroidal magnetic field. The radial profiles of plasma parameters measured at various toroidal locations show signatures of double layer formation in our system. Parametric dependence of double layer dynamics in presence of toroidal magnetic field is presented here.

Kumar Paul, Manash, E-mail: manashkr@gmail.com [Department of Physics, National Institute of Technology Agartala, Tripura–799 046 (India); Sharma, P. K.; Thakur, A.; Kulkarni, S. V.; Bora, D. [Institute for Plasma Research, Bhat, Gandhinagar, Gujarat–382 428 (India)

2014-06-15T23:59:59.000Z

302

Edinburgh Research Explorer Efficacious calculation of Raman spectra in high pressure  

E-Print Network [OSTI]

of sufficient size to perform neutron scattering at the required pressures, while the X-ray scattering cross

Millar, Andrew J.

303

A pedagogical introduction to quantum integrability, with a view towards theoretical high-energy physics  

E-Print Network [OSTI]

These are lecture notes of an introduction to quantum integrability given at the Tenth Modave Summer School in Mathematical Physics, 2014, aimed at PhD candidates and junior researchers in theoretical physics. We introduce spin chains and discuss the coordinate Bethe Ansatz (CBA) for a representative example: the Heisenberg XXZ model. The focus lies on the structure of the CBA and on its main results, deferring a detailed treatment of the CBA for the general $M$-particle sector of the XXZ model to an appendix. Subsequently the transfer-matrix method is discussed for the six-vertex model, uncovering a relation between that model and the XXZ spin chain. Equipped with this background the quantum inverse-scattering method (QISM) and algebraic Bethe Ansatz (ABA) are treated. We emphasize the use of graphical notation for algebraic quantities as well as computations. Finally we turn to quantum integrability in the context of theoretical high-energy physics. We discuss factorized scattering in two-dimensional QFT, a...

Lamers, J

2015-01-01T23:59:59.000Z

304

A View of Compatible Heat-Resistant Alloy and Coating Systems at High-Temperatures  

SciTech Connect (OSTI)

Conventional and advanced coatings were reviewed, and it was pointed out that the coated Ni-base superalloys decreased their creep rupture life significantly at higher temperatures, and the advanced high strength superalloy became more remarkably. Concept of diffusion barrier coating system (DBC system) and their formation process was introduced, and the results obtained for several heat-resistant alloys, stainless steel (SUS310S), Ni-Mo base alloy (Hastelloy-X), and 4{sup th} generation single crystal superalloy (TMS-138) were given. It was noted that creep-rupture life of the SUS310S and Hastelloy-X with the DBC system became longer than those of the bare alloys with or without conventional {beta}-NiAl coatings. This is due to slow creep-deformation of the Re-base alloy layer as the diffusion barrier. A novel concept based on combination of superalloys and coatings was proposed, by taking both the materials science and corrosion science into consideration.

Narita, Toshio [Specially Promoted Research Laboratory of Advanced Coatings, Hokkaido University, Kite-13 Nishi-8, Kita-Ku, Sapporo 060-8628 (Japan)

2009-09-14T23:59:59.000Z

305

Temperature induced immiscibility in the NaCl?H[subscript 2]O system at high pressure  

SciTech Connect (OSTI)

High-pressure polymorphs of H{sub 2}O are a major component in many outer planets, extra solar bodies, and icy satellites. This study sought to examine the influence of ionic impurities on the phase stability, thermal expansion, and melting curve of ice VII. Powder diffraction patterns of ice VII formed from pure H{sub 2}O and 5 wt.% NaCl aqueous solutions were taken at room temperature up to 11.1 {+-} 0.3 and 26.6 {+-} 0.4 GPa, respectively. Thermal expansions, {alpha}, of all ice VII samples were recorded and modeled up to the melting point of the samples. Ice VII formed from a NaCl-bearing aqueous solution at pressures greater than 2.2 GPa and less than 500 K can be indexed by ice VII only, whereas at temperatures greater than 500 K, diffraction lines indicative of halite (NaCl) are observed and become more intense with increasing temperature and only disappear at the melting point of the high-pressure ice. This phenomenon was observed in all NaCl-bearing ice samples that were heated to greater than 500 K. The melting curves of ice VII formed from pure H{sub 2}O and a 5 wt.% NaCl aqueous solution suggest that the presence of Na{sup +} and Cl{sup -} in the ice VII structure results in a depression of the melting curve by approximately 40 K. The exsolution of halite from the NaCl-doped ice VII and the depression of the ice VII melting curve suggest that the presence of ionic impurities in ice VII may promote the formation of a self-segregating zone deep within ice-rich bodies. This zone could initiate the formation of solute-rich melt pockets that may ascend toward the surface and result in surface manifestations such as solute-bearing aqueous vents, unexplained domes/diapirism, and/or salt-rich regions.

Frank, M.R.; Scott, H.P.; Maglio, S.J.; Prakapenka, V.B.; Shen, G. (NIU); (CIW); (UC); (Indiana)

2008-10-09T23:59:59.000Z

306

High-voltage nanosecond pulses in a low-pressure radio-frequency discharge  

Science Journals Connector (OSTI)

An influence of a high-voltage (3–17 kV) 20 ns pulse on a weakly-ionized low-pressure (0.1–10 Pa) capacitively coupled radiofrequency (RF) argon plasma is studied experimentally. The plasma evolution after pulse exhibits two characteristic regimes: a bright flash, occurring within 100 ns after the pulse (when the discharge emission increases by 2–3 orders of magnitude over the steady-state level), and a dark phase, lasting a few hundreds ?s (when the intensity of the discharge emission drops significantly below the steady-state level). The electron density increases during the flash and remains very large at the dark phase. 1D3V particle-in-cell simulations qualitatively reproduce both regimes and allow for detailed analysis of the underlying mechanisms. It is found that the high-voltage nanosecond pulse is capable of removing a significant fraction of plasma electrons out of the discharge gap, and that the flash is the result of the excitation of gas atoms, triggered by residual electrons accelerated in the electric field of immobile bulk ions. The secondary emission from the electrodes due to vacuum UV radiation plays an important role at this stage. High-density plasma generated during the flash provides efficient screening of the RF field (which sustains the steady-state plasma). This leads to the electron cooling and, hence, onset of the dark phase.

M. Y. Pustylnik; L. Hou; A. V. Ivlev; L. M. Vasilyak; L. Couëdel; H. M. Thomas; G. E. Morfill; V. E. Fortov

2013-06-10T23:59:59.000Z

307

Real-gas effects in the expansibility factor for subsonic differential-pressure flowmeters at high pressure  

SciTech Connect (OSTI)

Real-gas corrections in the expansibility factor are expressed by an equation of state (EOS). In this paper a virial EOS is introduced, with low-order virial coefficients calculated from a cubic EOS. The approach is composition-independent. EOS-dependent cancellations between real-gas effects are revealed. The current Intl. Organization for Standardization (ISO) standard is not always reliable for high-accuracy orifice measurements of gases with arbitrary composition.

Finjord, J. (Rogaland U. Center (NO))

1991-08-01T23:59:59.000Z

308

Effect of bituminous coal properties on carbon dioxide and methane high pressure sorption  

Science Journals Connector (OSTI)

Abstract High pressure sorption experiments with carbon dioxide and methane were carried out at a temperature of 45 °C and at pressures up to 15 MPa with three samples of methane-bearing, medium-rank coals in a moisture-equilibrated state using a manometric method. The samples were taken from selected positions of drill cores from exploration boreholes in the Bohemian part of the Upper Silesian Basin, and were characterized by a narrow range of degree of coalification and markedly different petrographic compositions, including a different mineral matter content. The total porosity of the coal samples was between 9% and 10%. A positive correlation was found between the equilibrium moisture in the coal samples and the total abundance of oxygen functional groups determined by FTIR. The excess sorption capacities ranged from 0.78 to 0.91 mmol g?1 for CO2 and from 0.45 to 0.52 mmol g?1 for CH4, and after recalculation to coal organic matter, the excess sorption capacities increased by up to 14% in the coal with the highest mineral fraction. The highest CO2/CH4 ratio was found in the sample that had the highest inertinite and liptinite content. The experimental isotherm data was fitted by modified Langmuir and Dubinin–Radushkevich sorption isotherms. The parameters obtained by these two methods were in good agreement for carbon dioxide. It was found that the sorption capacity of the organic matter in a coal sample with prevalence of inertinite (63.0 vol.%) was lower only by 14% for CO2 and by 18% for CH4 than the sorption capacity of the organic matter in a coal sample with prevalence of vitrinite (65.3 vol.%). This provided confirmation that the petrographic composition of a coal has an ambiguous effect.

Zuzana Weishauptová; Old?ich P?ibyl; Ivana Sýkorová; Vladimír Machovi?

2015-01-01T23:59:59.000Z

309

Direct ion flux measurements at high-pressure-depletion conditions for microcrystalline silicon deposition  

SciTech Connect (OSTI)

The contribution of ions to the growth of microcrystalline silicon thin films has been investigated in the well-known high-pressure-depletion (HPD) regime by coupling thin-film analysis with plasma studies. The ion flux, measured by means of a capacitive probe, has been studied in two regimes, i.e., the amorphous-to-microcrystalline transition regime and a low-to-high power regime; the latter regime had been investigated to evaluate the impact of the plasma power on the ion flux in collisional plasmas. The ion flux was found not to change considerably under the conditions where the deposited material undergoes a transition from the amorphous to the microcrystalline silicon phase; for solar-grade material, an ion-to-Si deposition flux of ?0.30 has been determined. As an upper-estimation of the ion energy, a mean ion energy of ?19 eV has been measured under low-pressure conditions (<1 mbar) by means of a retarding field energy analyzer. Combining this upper-estimate with an ion per deposited Si atom ratio of ?0.30, it is concluded that less than 6 eV is available per deposited Si atom. The addition of a small amount of SiH{sub 4} to an H{sub 2} plasma resulted in an increase of the ion flux by about 30% for higher power values, whereas the electron density, deduced from optical emission spectroscopy analysis, decreased. The electron temperature, also deduced from optical emission spectroscopy analysis, reveals a slight decrease with power. Although the dominant ion in the HPD regime is SiH{sub 3}{sup +}, i.e., a change from H{sub 3}{sup +} in pure hydrogen HPD conditions, the measured larger ion loss can be explained by assuming steeper electron density profiles. These results, therefore, confirm the results reported so far: the ion-to-Si deposition flux is relatively large but has neither influence on the microcrystalline silicon film properties nor on the phase transition. Possible explanations are the reported high atomic hydrogen to deposition flux ratio, mitigating the detrimental effects of an excessive ion flux.

Bronneberg, A. C.; Kang, X.; Palmans, J.; Janssen, P. H. J.; Lorne, T. [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands)] [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands); Creatore, M. [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands) [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands); Solliance Solar Research, High Tech Campus 5, 5656AE Eindhoven (Netherlands); Sanden, M. C. M. van de [Applied Physics Department, Eindhoven University of Technology, P.O. Box 513, 5600MB Eindhoven (Netherlands); Dutch Institute for Fundamental Energy Research (DIFFER), P.O. Box 1207, 3430BE Nieuwegein (Netherlands)

2013-08-14T23:59:59.000Z

310

High-Pressure Micellar Solutions of Symmetric and Asymmetric Styrene?Diene Diblocks in Compressible Near Critical Solvents: Micellization Pressures and Cloud Pressures Respond but Micellar Cloud Pressures Insensitive to Copolymer Molecular Weight, Concentration, and Block Ratio Changes  

SciTech Connect (OSTI)

Micellar solutions of polystyrene-block-polybutadiene and polystyrene-block-polyisoprene in propane are found to exhibit significantly lower cloud pressures than the corresponding hypothetical nonmicellar solutions. Such a cloud-pressure reduction indicates the extent to which micelle formation enhances the apparent diblock solubility in near-critical and hence compressible propane. Concentration-dependent pressure-temperature points beyond which no micelles can be formed, referred to as the micellization end points, are found to depend on the block type, size, and ratio. The cloud-pressure reduction and the micellization end point measured for styrene-diene diblocks in propane should be characteristic of all amphiphilic diblock copolymer solutions that form micelles in compressible solvents.

Winoto, Winoto [University of Wyoming, Laramie; Tan, Sugata [University of Wyoming, Laramie; Shen, Youqin [University of Wyoming, Laramie; Radosz, Maciej [University of Wyoming, Laramie; Hong, Kunlun [ORNL; Mays, Jimmy [ORNL

2009-01-01T23:59:59.000Z

311

Time resolved optical spectroscopy to examine chemical decomposition of energetic materials under static high pressure and pulsed heating conditions  

SciTech Connect (OSTI)

The study of the deflagration or detonation reactions of energetic materials is challenging due to the high pressure, high temperature, and time domain under which the reactions occur. Experimental measurements are presented that demonstrate the ability to continuously monitor the global reaction times and reaction sequences associated with chemical reactions under these conditions. Time resolved absorption spectroscopy is used in conjunction with a high pressure gem anvil cell to probe the real-time chemical processes during pulsed-heating. Samples are initiated by a rapid thermal jump induced by absorption of a single laser pulse. Time resolved absorption spectroscopy of 3,6 trinitroethylamine tetrazine reaction is demonstrated by the real time measurement of the decrease in the {pi}-{pi}* absorption at 100 ns temporal resolution during laser heating at pressures up to 3.5 GPa.

Russell, T.P. [Naval Research Lab., Washington, DC (United States). Chemistry Div.; Allen, T.M.; Gupta, Y.M. [Washington State Univ., Pullman, WA (United States). Shock Dynamics Center

1996-07-01T23:59:59.000Z

312

High-Temperature Phase Transitions in CsH2PO4 Under Ambient and High-Pressure Conditions: A Synchrotron X-ray Diffraction Study  

SciTech Connect (OSTI)

To clarify the microscopic origin of the temperature-induced three-order-of-magnitude jump in the proton conductivity of CsH2PO4 (superprotonic behavior), we have investigated its crystal structure modifications within the 25-300 C temperature range under both ambient- and high-pressure conditions using synchrotron x-ray diffraction. Our high-pressure data show no indication of the thermal decomposition/polymerization at the crystal surface recently proposed as the origin of the enhanced proton conductivity. Instead, we found direct evidence that the superprotonic behavior of the title material is associated with a polymorphic structural transition to a high-temperature cubic phase. Our results are in excellent agreement with previous high-pressure ac impedance measurements.

Botez,C.; Hermosillo, J.; Zhang, J.; Qian, J.; Zhao, Y.; Majzlan, J.; Chianelli, R.; Pantea, C.

2007-01-01T23:59:59.000Z

313

High-pressure Storage Vessels for Hydrogen, Natural Gas and Hydrogen-Natural Gas Blends  

Broader source: Energy.gov [DOE]

These slides were presented at the International Hydrogen Fuel and Pressure Vessel Forum on September 27 – 29, 2010, in Beijing, China.

314

High-pressure Storage Vessels for Hydrogen, Natural Gas andHydrogen...  

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

Gas and Blends - Materials Testing and Design Requirements for Hydrogen Components and Tanks International Hydrogen Fuel and Pressure Vessel Forum 2010 Proceedings Hydrogen...

315

High pressure elasticity and phase transformation in brucite, Mg(OH)2  

Science Journals Connector (OSTI)

The first pressure derivatives of the second-order elastic constants $${\\rm d}C^{\\prime}_{IJ}/{\\rm d}p$$ have been ca...

K. P. Jayachandran; Lin-gun Liu

2006-10-01T23:59:59.000Z

316

Structural Investigation of Methane Hydrate Sediments by Microfocus X-ray Computed Tomography Technique under High-Pressure Conditions  

Science Journals Connector (OSTI)

The structure of natural gas hydrate sediments was observed by microfocus X-ray computed tomography (CT). A newly developed high-pressure vessel for the microfocus X-ray CT system was applied to observe the sediments at a temperature above 273 K and under high-pressure conditions. The obtained two-dimensional CT images clearly showed the spatial distribution of the free-gas pore, sand particles, water, and hydrates. These results demonstrated that microfocus X-ray CT can be effective for studying natural gas hydrate sediment samples.

Shigeki Jin; Jiro Nagao; Satoshi Takeya; Yusuke Jin; Junko Hayashi; Yasushi Kamata; Takao Ebinuma; Hideo Narita

2006-01-01T23:59:59.000Z

317

The effect of high-pressure injection of gas on the reservoir volume factor of a crude oil  

E-Print Network [OSTI]

THE EFFECT OF HIGH-PRESSURE INJECTION OF GAS ON THE RESERVOIR VOLUME FACTOR OF A CRUDE OIL A Thesis By+ BAXTER DS'kONEYCUTT o Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE August, i957 Major Subject: Petroleum Engineering THE EFFECT OF HIGH-PRESSURE INJECTION OF GAS ON THE RESERVOIR VOLUME FACTOR OF A CRUDE OIL A Thesis By BAXTER D. HONEYCUTT Appro d as to style...

Honeycutt, Baxter Bewitt

2012-06-07T23:59:59.000Z

318

Novel, fiber optic, hybrid pressure and temperature sensor designed for high-temperature gen-IV reactor applications  

SciTech Connect (OSTI)

A novel, fiber optic, hybrid pressure-temperature sensor is presented. The sensor is designed for reliable operation up to 1050 C, and is based on the high-temperature fiber optic sensors already demonstrated during previous work. The novelty of the sensors presented here lies in the fact that pressure and temperature are measured simultaneously with a single fiber and a single transducer. This hybrid approach will enable highly accurate active temperature compensation and sensor self-diagnostics not possible with other platforms. Hybrid pressure and temperature sensors were calibrated by varying both pressure and temperature. Implementing active temperature compensation resulted in a ten-fold reduction in the temperature-dependence of the pressure measurement. Sensors were also tested for operability in a relatively high neutron radiation environment up to 6.9x10{sup 17} n/cm{sup 2}. In addition to harsh environment survivability, fiber optic sensors offer a number of intrinsic advantages for nuclear power applications including small size, immunity to electromagnetic interference, self diagnostics / prognostics, and smart sensor capability. Deploying fiber optic sensors on future nuclear power plant designs would provide a substantial improvement in system health monitoring and safety instrumentation. Additional development is needed, however, before these advantages can be realized. This paper will highlight recent demonstrations of fiber optic sensors in environments relevant to emerging nuclear power plants. Successes and lessons learned will be highlighted. (authors)

Palmer, M. E.; Fielder, R. S.; Davis, M. A. [Luna Innovations, Incorporated, 2851 Commerce St., Blacksburg, VA 24060 (United States)

2006-07-01T23:59:59.000Z

319

Inter-stage and Performance Tests of a Two-stage High-pressure Turbine  

E-Print Network [OSTI]

traverse system in TPFL. Performance tests were conducted for varying pressure ratio, at fixed rotational speed and for varying rotational speed with fixed pressure ratio and the efficiency was plotted against u/c_0. Each condition was tested and measured...

Sharma, Kapil

2011-08-08T23:59:59.000Z

320

High-pressure single-crystal X-ray diffraction facilities on station 9.8 at the SRS Daresbury Laboratory - hydrogen location in the high-pressure structure of ethanol  

Science Journals Connector (OSTI)

A new high-pressure single-crystal diffraction facility constructed on station 9.8 at the Synchrotron Radiation Source, Daresbury Laboratory, is described. Initial results on the low-melting-point compound ethanol are presented; diffraction data were of sufficient quality to enable H-atoms to be located.

Allan, D.R.

2001-01-01T23:59:59.000Z

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


321

High-rate HMDSO-based coatings in open air using atmospheric-pressure plasma jet  

Science Journals Connector (OSTI)

This work deals with the high-rate and dust-free formation of carbon-containing silicon oxide (SiOC) coatings in open air without substrate heating using an atmospheric-pressure (AP) plasma jet. The AP plasma was excited by a 13.56-MHz radio frequency (RF) power. Hexamethyldisiloxane and oxygen (O2) were used as the source gases. By optimizing the O2 flow rate and RF power, SiOC films were readily fabricated at deposition rates higher than 100 nm/s without suffering from particulate contaminations of the film surface. Additionally, an inorganic SiO2-like film exhibiting O/Si atomic ratio of approximately 2 was obtained at a deposition rate of ~ 13 nm/s, the value of which is still greater than those obtained in other AP plasma sources. Further systematic studies are needed to see if good-quality inorganic SiO2-like films can be obtained with higher rates.

H. Kakiuchi; K. Higashida; T. Shibata; H. Ohmi; T. Yamada; K. Yasutake

2012-01-01T23:59:59.000Z

322

High-pressure turbine deposition in land-based gas turbines from various synfuels  

SciTech Connect (OSTI)

Ash deposits from four candidate power turbine synfuels were studied in an accelerated deposition test facility. The facility matches the gas temperature and velocity of modern first-stage high-pressure turbine vanes. A natural gas combustor was seeded with finely ground fuel ash particulate from four different fuels: straw, sawdust, coal, and petroleum coke. The entrained ash particles were accelerated to a combustor exit flow Mach number of 0.31 before impinging on a thermal barrier coating (TBC) target coupon at 1150{sup o}C. Postexposure analyses included surface topography, scanning electron microscopy and x-ray spectroscopy. Due to significant differences in the chemical composition of the various fuel ash samples, deposit thickness and structure vary considerably for fuel. Biomass products (e.g., sawdust and straw) are significantly less prone to deposition than coal and petcoke for the same particle loading conditions. In a test simulating one turbine operating year at a moderate particulate loading of 0.02 parts per million by weight, deposit thickness from coal and petcoke ash exceeded 1 and 2 mm, respectively. These large deposits from coal and petcoke were found to detach readily from the turbine material with thermal cycling and handling. The smaller biomass deposit samples showed greater tenacity, in adhering to the TBC surface. In all cases, corrosive elements (e.g., Na, K, V, Cl, S) were found to penetrate the TBC layer during the accelerated deposition test. Implications for the power generation goal of fuel flexibility are discussed.

Bons, J.P.; Crosby, J.; Wammack, J.E.; Bentley, B.I.; Fletcher, T.H. [Brigham Young University, Provo, UT (United States). Dept. of Mechanical Engineering

2007-01-15T23:59:59.000Z

323

An improved measurement of electron-ion recombination in high-pressure xenon gas  

E-Print Network [OSTI]

We report on results obtained with the NEXT-DEMO prototype of the NEXT-100 high-pressure xenon gas time projection chamber (TPC), exposed to an alpha decay calibration source. Compared to our previous measurements with alpha particles, an upgraded detector and improved analysis techniques have been used. We measure event-by-event correlated fluctuations between ionization and scintillation due to electron-ion recombination in the gas, with correlation coeffcients between -0.80 and -0.56 depending on the drift field conditions. By combining the two signals, we obtain a 2.8 % FWHM energy resolution for 5.49 MeV alpha particles and a measurement of the optical gain of the electroluminescent TPC. The improved energy resolution also allows us to measure the specific activity of the radon in the gas due to natural impurities. Finally, we measure the average ratio of excited to ionized atoms produced in the xenon gas by alpha particles to be $0.561\\pm 0.045$, translating into an average energy to produce a primary scintillation photon of $W_{\\rm ex}=(39.2\\pm 3.2)$ eV.

NEXT Collaboration; L. Serra; M. Sorel; V. Álvarez; F. I. G. Borges; M. Camargo; S. Cárcel; S. Cebrián; A. Cervera; C. A. N. Conde; T. Dafni; J. Díaz; R. Esteve; L. M. P. Fernandes; P. Ferrario; A. L. Ferreira; E. D. C. Freitas; V. M. Gehman; A. Goldschmidt; J. J. Gómez-Cadenas; D. González-Díaz; R. M. Gutiérrez; J. Hauptman; J. A. Hernando Morata; D. C. Herrera; I. G. Irastorza; L. Labarga; A. Laing; I. Liubarsky; N. Lopez-March; D. Lorca; M. Losada; G. Luzón; A. Marí; J. Martín-Albo; G. Martínez-Lema; A. Martínez; T. Miller; F. Monrabal; M. Monserrate; C. M. B. Monteiro; F. J. Mora; L. M. Moutinho; J. Muñoz Vidal; M. Nebot-Guinot; D. Nygren; C. A. B. Oliveira; J. Pérez; J. L. Pérez Aparicio; M. Querol; J. Renner; L. Ripoll; A. Rodríguez; J. Rodríguez; F. P. Santos; J. M. F. dos Santos; D. Shuman; A. Simón; C. Sofka; J. F. Toledo; J. Torrent; Z. Tsamalaidze; J. F. C. A. Veloso; J. A. Villar; R. Webb; J. T. White; N. Yahlali

2015-02-03T23:59:59.000Z

324

An improved measurement of electron-ion recombination in high-pressure xenon gas  

E-Print Network [OSTI]

We report on results obtained with the NEXT-DEMO prototype of the NEXT-100 high-pressure xenon gas time projection chamber (TPC), exposed to an alpha decay calibration source. Compared to our previous measurements with alpha particles, an upgraded detector and improved analysis techniques have been used. We measure event-by-event correlated fluctuations between ionization and scintillation due to electron-ion recombination in the gas, with correlation coeffcients between -0.80 and -0.56 depending on the drift field conditions. By combining the two signals, we obtain a 2.8 % FWHM energy resolution for 5.49 MeV alpha particles and a measurement of the optical gain of the electroluminescent TPC. The improved energy resolution also allows us to measure the specific activity of the radon in the gas due to natural impurities. Finally, we measure the average ratio of excited to ionized atoms produced in the xenon gas by alpha particles to be $0.561\\pm 0.045$, translating into an average energy to produce a primary s...

Serra, L; Álvarez, V; Borges, F I G; Camargo, M; Cárcel, S; Cebrián, S; Cervera, A; Conde, C A N; Dafni, T; Díaz, J; Esteve, R; Fernandes, L M P; Ferrario, P; Ferreira, A L; Freitas, E D C; Gehman, V M; Goldschmidt, A; Gómez-Cadenas, J J; González-Díaz, D; Gutiérrez, R M; Hauptman, J; Morata, J A Hernando; Herrera, D C; Irastorza, I G; Labarga, L; Laing, A; Liubarsky, I; Lopez-March, N; Lorca, D; Losada, M; Luzón, G; Marí, A; Martín-Albo, J; Martínez-Lema, G; Martínez, A; Miller, T; Monrabal, F; Monserrate, M; Monteiro, C M B; Mora, F J; Moutinho, L M; Vidal, J Muñoz; Nebot-Guinot, M; Nygren, D; Oliveira, C A B; Pérez, J; Aparicio, J L Pérez; Querol, M; Renner, J; Ripoll, L; Rodríguez, A; Rodríguez, J; Santos, F P; Santos, J M F dos; Shuman, D; Simón, A; Sofka, C; Toledo, J F; Torrent, J; Tsamalaidze, Z; Veloso, J F C A; Villar, J A; Webb, R; White, J T; Yahlali, N

2014-01-01T23:59:59.000Z

325

Structural Evidence for a Fast-Ion Transition in the High-Pressure Rocksalt Phase of Silver Iodide  

Science Journals Connector (OSTI)

This Letter describes neutron diffraction measurements of the rocksalt structured phase of AgI at high pressure and temperature and the structural disorder which accompanies its high conductivity. In contrast to the first-order structural phase transition which results in fast-ionic ?-AgI at ambient pressure, the fast-ionic behavior in rocksalt structured AgI occurs above a diffuse transition with a small anomaly in lattice parameter and a continuous increase in occupation of interstitial tetrahedral sites with increasing temperature. There are approximately 10 times more defects in the fast-ionic phase of rocksalt AgI than in isostructural AgBr at ambient pressure, 1 K below melting.

D. A. Keen; S. Hull; W. Hayes; N. J. G. Gardner

1996-12-09T23:59:59.000Z

326

A numerical study of the supply mode effects on high-pressure mercury discharge lamp dynamic thermal behavior  

SciTech Connect (OSTI)

This paper presents a numerical study of the dynamic behavior of high-pressure mercury discharge lamp as a function of supply mode. Bidimensional time-dependent equations have been solved by using a semi-implicit finite-element code. The model has been developed in the frame of the local thermodynamic equilibrium hypothesis. After validation by using experimental data from the literature, this model was applied to analyze the effects of some key parameters such as frequency for an ac arc current and the ratio cycle parameter for square arc-current wave form on the convective process. The results obtained have been used to analyze the dynamic thermal behavior of high-pressure mercury plasma (pressure equal to 0.3 MPa) working under currents widely different in frequency and wave form.

Kaziz, S.; Ahmed, R. Ben; Araoud, Z.; Gazzah, M.H.; Charrada, K.; Said, R. [EMIR, IPEIM, route de Skanes, 5019 Monastir (Tunisia); FSM, avenue de l'environnement, 5019 Monastir (Tunisia); EMIR, IPEIM, route de Skanes, 5019 Monastir (Tunisia)

2005-06-15T23:59:59.000Z

327

Computer simulations of cavitation collapses at high static pressure using hydrocode HYADES: Plasma conditions and shock waves in the liquid  

Science Journals Connector (OSTI)

Previously (JASA 121 pt.2 p. 3181) transient cavitation in high pressure spherical resonators was described. The phenomenon is characterized by cavitation events lasting a few ms (100 s acoustic cycles) in which a cavity (or cavities) collapse violently emitting flashes of light of widths ?1–40 nsec and spherical shock waves with amplitudes ?1–100 bars (depending on the static pressure) at a distance of 10 cm from the collapse. Both SL and shock amplitudes are proportional to the static pressure. The goal of these experiments is to investigate how the static pressure increases the intensity of acoustic cavitation collapse and whether thermonuclear fusion reactions are possible this way. The determination of plasma temperatures pressures and densities is therefore critical in making progress. Furthermore the amplitude and velocity of the shock waves can be used to determine the conditions at stagnation (end of collapse) assuming the cavity size at that time is known. To this end results of numerical simulations using HYADES plasma physics hydrocode will be presented with emphasis on the plasma conditions versus the amount of gas in the cavity and the static pressure as well as the amplitude and velocity of the outgoing shock waves generated after the collapse [Work supported by SMDC Contract No. W9113M?07?C?0178.

D. Felipe Gaitan; Ross A. Tessien; Robert A. Hiller; Jeff Alstadter

2007-01-01T23:59:59.000Z

328

The Unique High-Pressure Behavior of Curium Probed Further Using Alloys  

SciTech Connect (OSTI)

The changing role of the 5f electrons across the actinide series has been of prime interest for many years. The remarkable behavior of americium's 5f electrons under pressure was determined experimentally a few years ago and it precipitated a strong interest in the heavy element community. Theoretical treatments of americium's behavior under pressure followed and continue today. Experimental and theoretical findings regarding curium's behavior under pressure have shown that the pressure behavior of curium was not a mirror image of that for americium. Rather, one of the five crystallographic phases observed with curium (versus four for americium) was a unique monoclinic structure whose existence is due to a spin stabilization effect by curium's 5f{sup 7} electronic configuration and its half-filled 5f-shell. We review briefly the behavior of pure curium under pressure but focus on the pressure behaviors of three curium alloys with the intent of comparing them with pure curium. An important experimental finding confirmed by theoretical computations, is that dilution of curium with its near neighbors is sufficient to prevent the formation of the unique C2/c phase that appears in pure Cm metal under pressure. As this unique C2/c phase is very sensitive to having a 5f{sup 7} configuration to maximize the magnetic spin polarization, dilution of this state with adjacent actinide neighbors reduces its stability.

Heathman, S. [European Commission Joint Research Centre; Haire, Richard {Dick} G [ORNL; LeBihan, T. [CEA-Centre de Valduc, Is-sur-Tille, France; Ahuja, R. [Uppsala University, Uppsala, Sweden; Li, S. [Virginia Commonwealth University, Richland; Luo, W. [Uppsala University, Uppsala, Sweden; Johansson, B. [Royal Institute of Technology, Stockholm, Sweden

2007-01-01T23:59:59.000Z

329

Cost-effective upgrade of a focusing system for inelastic X-ray scattering experiments under high pressure  

Science Journals Connector (OSTI)

This paper describes a scheme utilizing a set of low-cost and compact Kirkpatrick-Baez mirrors for upgrading the optical system of the Taiwan Inelastic X-ray Scattering beamline at SPring-8 for high-pressure experiments using diamond-anvil cells. The scheme as implemented improves the focus to 13 µm × 16 µm with transmission of up to 72%.

Huang, C.-Y.

2007-12-18T23:59:59.000Z

330

Vehicle Technologies Office 2013 Merit Review: A University Consortium on Efficient and Clean High-Pressure, Lean Burn (HPLB) Engines  

Broader source: Energy.gov [DOE]

A presentation given by the University of Michigan at the 2013 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Program Annual Merit Review and Peer Evaluation Meeting about a university consortium to research efficient and clean high-pressure lean burn engines.

331

Physics of the Earth and Planetary Interiors xxx (2004) xxxxxx High pressure crystal chemistry of hydrous ringwoodite  

E-Print Network [OSTI]

Physics of the Earth and Planetary Interiors xxx (2004) xxx­xxx High pressure crystal chemistry of hydrous ringwoodite and water in the Earth's interior Joseph R. Smytha,, Christopher M. Holla, Daniel J November 2002; received in revised form 12 May 2003; accepted 18 August 2003 Abstract The crystal chemistry

Smyth, Joseph R.

332

Physics of the Earth and Planetary Interiors 143144 (2004) 271278 High pressure crystal chemistry of hydrous ringwoodite  

E-Print Network [OSTI]

Physics of the Earth and Planetary Interiors 143­144 (2004) 271­278 High pressure crystal chemistry of hydrous ringwoodite and water in the Earth's interior Joseph R. Smytha,, Christopher M. Holla, Daniel J November 2002; received in revised form 12 May 2003; accepted 18 August 2003 Abstract The crystal chemistry

Jacobsen, Steven D.

333

Tropical coasts are highly vulnerable to climatic pressures, the future impacts of which are projected to propagate  

E-Print Network [OSTI]

Tropical coasts are highly vulnerable to climatic pressures, the future impacts of which are projected to propagate through the natural and human components of coastal systems. One single event (e the resilience of the whole system. Risks related to climate change are frequently examined in isolation through

Boyer, Edmond

334

An investigation of high pressure/late cycle injection of CNG (compressed natural gas) as a fuel for rail applications  

SciTech Connect (OSTI)

This report describes a demonstration effort to investigate the use of natural gas in a medium-speed diesel engine. The effort was unique in the sense that natural gas was injected directly into the combustion chamber late in the compression stroke, as a high pressure gas rather than through low pressure fumigation or low pressure injection early in the compression stroke. Tests were performed on a laboratory two-cylinder, two-stroke cycle medium-speed diesel engine in an attempt to define its ability to operate on the high pressure/late cycle injection concept and to define the performance and emission characteristics of the engine under such operation. A small quantity of No.-2 diesel fuel was injected into the cylinder slightly before the gas injection to be used as an ignition source for the gas. Pilot (diesel fuel) and main (natural gas) timing and injection duration were systematically varied to optimize engine performance. The test demonstrated that the medium-speed engine was capable of attaining full rated speed and load (unlike the low pressure approach) with very low percentages of pilot injection with the absence of knock. Thermal efficiency was as much as 10 percent less than thermal efficiency levels obtained with neat diesel fuel. This was primarily due to the placement and injection characteristics of the pilot and main injectors. Optimization of the injection system would undoubtedly result in increased thermal efficiency. 11 figs., 4 tabs.

Wakenell, J.F.; O'Neal, G.G.; Baker, Q.A.; Urban, C.M.

1988-04-01T23:59:59.000Z

335

Structural phase transitions in EuFe[subscript 2]As[subscript 2] superconductor at low temperatures and high pressures  

SciTech Connect (OSTI)

The crystal structure of EuFe{sub 2}As{sub 2} has been studied up to a pressure of 35 GPa and down to a temperature of 8 K using temperature dependent x-ray diffraction in a diamond anvil cell at a synchrotron source. At 4.3 GPa, we have detected a structural phase transition from a high temperature tetragonal phase with I4/mmm space group to a low temperature orthorhombic phase with Fmmm space group around 120 K. With the application of pressure at a low temperature of 10 K, the orthorhombic phase is suppressed and a phase change to a collapsed tetragonal phase with I4/mmm space group is observed at 11 GPa. This collapsed tetragonal phase is similar to the one observed at ambient temperature and pressure above 8.5 GPa. We have shown that the collapsed tetragonal phase of EuFe{sub 2}As{sub 2} has the same pressure-volume (P-V) equation of state at ambient temperature and at 10 K, implying that the high pressure phase of EuFe{sub 2}As{sub 2} has a negligible thermal expansion coefficient.

Uhoya, Walter O.; Tsoi, Georgiy M.; Vohra, Yogesh K.; McGuire, Michael A.; Sefat, Athena S. (UAB); (ORNL)

2011-09-20T23:59:59.000Z

336

High pressure feeder and method of operating to feed granular or fine materials  

SciTech Connect (OSTI)

A coal feed system to feed pulverized low rank coals containing up to 25 wt % moisture to gasifiers operating up to 1000 psig pressure is described. The system includes gas distributor and collector gas permeable pipes imbedded in the lock vessel. Different methods of operation of the feed system are disclosed to minimize feed problems associated with bridging and packing of the pulverized coal. The method of maintaining the feed system and feeder device exit pressures using gas addition or extraction with the pressure control device is also described.

Vimalchand, Pannalal; Liu, Guohai; Peng, Wan Wang

2014-10-07T23:59:59.000Z

337

/home/jla/dart/asp_seminar/slides1.fm March 18, 2002 A Highly Biased View of the `ART' of Data Assimilation  

E-Print Network [OSTI]

/home/jla/dart/asp_seminar/slides1.fm March 18, 2002 A Highly Biased View of the `ART' of Data of existing observations F. Evaluating future observing systems H. Adaptive observations #12;/home/jla/dart/asp_seminar/slides sort of `attractor' _________________________________________________ #12;/home/jla/dart/asp_seminar/slides

338

High-pressure synthesis and characterization of the first cerium fluoride borate CeB{sub 2}O{sub 4}F  

SciTech Connect (OSTI)

CeB{sub 2}O{sub 4}F is the first cerium fluoride borate, which is exclusively built up of one-dimensional, infinite chains of condensed trigonal-planar [BO{sub 3}]{sup 3?} groups. This new cerium fluoride borate was synthesized under high-pressure/high-temperature conditions of 0.9 GPa and 1450 °C in a Walker-type multianvil apparatus. The compound crystallizes in the orthorhombic space group Pbca (No. 61) with eight formula units and the lattice parameters a=821.63(5), b=1257.50(9), c=726.71(6) pm, V=750.84(9) Å{sup 3}, R{sub 1}=0.0698, and wR{sub 2}=0.0682 (all data). The structure exhibits a 9+1 coordinated cerium ion, one three-fold coordinated fluoride ion and a one-dimensional chain of [BO{sub 3}]{sup 3?} groups. Furthermore, IR spectroscopy, Electron Micro Probe Analysis and temperature-dependent X-ray powder diffraction measurements were performed. - Graphical abstract: A new rare-earth fluoride borate CeB{sub 2}O{sub 4}F could be synthesized under high-pressure/high-temperature conditions of 0.9 °GPa and 1450 °Cin a Walker-type multianvil apparatus. The crystal structure represents a new structure type in the class of rare-earth fluoride borates. The structure exhibits a 9+1 coordinated cerium ion, one three-fold coordinated fluoride ion and a one-dimensional chain of [BO{sub 3}]{sup 3?} groups. A closer view on the ac-plane shows an interesting wave-like modulation of the borate chains. Highlights: • CeB{sub 2}O{sub 4}F is the first fluoride borate exclusively built up of one-dimensional, infinite chains of condensed trigonal-planar [BO{sub 3}]{sup 3?} groups. • CeB{sub 2}O{sub 4}F is the first cerium fluoride borate. • High-pressure conditions were necessary to synthesize CeB{sub 2}O{sub 4}F.

Hinteregger, Ernst; Wurst, Klaus [Institut für Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universität Innsbruck, Innrain 80-82, A-6020 Innsbruck (Austria); Tribus, Martina [Institut für Mineralogie und Petrographie, Leopold-Franzens-Universität Innsbruck, Innrain 52 f, A-6020 Innsbruck (Austria); Huppertz, Hubert, E-mail: hubert.huppertz@uibk.ac.at [Institut für Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universität Innsbruck, Innrain 80-82, A-6020 Innsbruck (Austria)

2013-08-15T23:59:59.000Z

339

High-pressure elasticity of sodium majorite garnet, Na2MgSi5O12  

Science Journals Connector (OSTI)

...Ceperley and Adler 1980; Perdew and Wang 1986; Perdew et al. 1991, 1996...pressure derivatives were reported. a Synchroton X-ray diffraction (Dymshits et...1895-1898. Perdew, J.P. and Wang, Y. (1986) Accurate and simple...

Mainak Mookherjee

340

Analytical and experimental evaluation of the leakage and stiffness characteristics of high pressure pocket damper seals  

E-Print Network [OSTI]

This thesis presents numerical predictions for the leakage and direct stiffness coefficients of pocket damper seals. Modifications made to earlier flow-prediction models are discussed. Leakage and static pressure measurements on straight...

Gamal Eldin, Ahmed Mohamed

2004-09-30T23:59:59.000Z

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


341

High-pressure neutron diffraction study on H–D isotope effects in brucite  

Science Journals Connector (OSTI)

A neutron powder diffraction study of hydrogenated and deuterated brucite was conducted at ambient temperature and at...a axis, parallel to the sheets of Mg–O octahedra, decrease only slightly with pressure with ...

Juske Horita; António M. dos Santos…

2010-12-01T23:59:59.000Z

342

Atmospheric-pressure plasma treatment of ultra-high-molecular-weight polypropylene fabric  

Science Journals Connector (OSTI)

Effects of an atmospheric pressure surface discharge on a woven ultrahigh molecular weight polyethylene fabric were studied. Our results show that the surface discharge can be used to achieve a higher long-ter...

J. Ráhel’; M. ?ernák; I. Hudec; A. Brablec; D. Trunec…

2000-03-01T23:59:59.000Z

343

High strain rate mechanical characterization of trabecular bone utilizing the split-Hopkinson pressure bar technique  

E-Print Network [OSTI]

The split-Hopkinson pressure bar (SHPB) technique has been in use in one form or another for more than fifty years and has recently gained a great deal of attention for its ability to characterize materials such as metals, ...

Johnson, Timothy Paul Mahal

2005-01-01T23:59:59.000Z

344

An Estimate of the Thermodynamic Pressure in High-Energy Collisions  

E-Print Network [OSTI]

We introduce a novel approach to estimate the thermodynamic pressure from heavy-ion collisions based on recently measured higher-order moments of particle multiplicities by the STAR experiment. We start with fitting the experimental results in the most-central collisions. Then, we integrate them back to lower ones. For example, we find that the first-order moment, the mean multiplicity, is exactly reproduced from the integral of variance, the second-order moment. Therefore, the zero-order moment, the thermodynamic pressure, can be estimated from the integral of the mean multiplicity. the possible comparison between such a kind of pressure (deduced from the integral of particle multiplicity) and the lattice pressure and the relating of Bjorken energy density to the lattice energy density are depending on lattice QCD at finite baryon chemical potential and first-principle estimation of the formation time of the quark-gluon plasma (QGP).

Tawfik, Abdel Nasser

2015-01-01T23:59:59.000Z

345

An examination of possible reversible combustion at high temperatures and pressures for a reciprocating engine  

E-Print Network [OSTI]

ratio of 18. Although the temperatures and pressures considered are well beyond practical values for the materials and designs of today, the general result of the study is that conditions can be identified to eliminate the combustion irreversibility....

Patrawala, Kaushik Tanvir

2009-05-15T23:59:59.000Z

346

A new high-pressure form of MgAl2O4  

Science Journals Connector (OSTI)

... temperature were also made on the basis of phase transitions in Mg2SiO4 (olivine to modified spinel) and MgSiO3 (ilmenite to perovskite). Uncertainties in pressure measurements were around ±0. ... in pressure measurements were around ±0.5 GPa. Our starting material was single-crystal spinel of pure MgAl2O4 (supplied by Union Carbide Co., USA), which was crushed ...

T. Irifune; K. Fujino; E. Ohtani

1991-01-31T23:59:59.000Z

347

The analysis and specification of large high-pressure, high-temperature valves for combustion turbine protection in second-generation PFB power plants: Topical report  

SciTech Connect (OSTI)

The purpose of this study was to provide a specification for the high-pressure/high-temperature valves for turbine overspeed protection in a commercial-scale second-generation pressurized fluidized bed combustion (PFBC) power plant. In the event of a loss of external (generator) load, the gas turbine rapidly accelerates from its normal operating speed. Protection from excessive overspeed can be maintained by actuation of fuel isolation and air bypass valves. A design specification for these valves was developed by analyses of the turbine/compressor interaction during a loss of load and analyses of pressure and flow transients during operation of the overspeed protection valves. The basis for these analyses was the Phase 1 plant conceptual design prepared in 1987.

Not Available

1994-08-01T23:59:59.000Z

348

Vacuum ultra-violet emission of plasma discharges with high Xe partial pressure using a cathode protective layer with high secondary electron emission  

SciTech Connect (OSTI)

In this work, the mechanism of the vacuum ultra-violet (VUV) emission of plasma discharges, with high Xe partial pressure and high ion-induced secondary electrons emission protective layer, is studied by measuring the VUV light emission directly and comparing it with two-dimensional simulations. From the panel measurement, we find that the high intensity of excimer VUV mainly contributes to the high luminous efficacy of SrCaO-plasma display panels (PDP) at a low sustain voltage. The unchanged Xe excitation efficiency indicates that the electron temperature is not decreased by the high secondary electrons emission protective layer, even though the sustain voltage is much lower. From the two-dimensional simulations, we can find that the ratio of excimer VUV to resonant VUV, which is determined by the collision rate in the discharge, is only significantly affected by the Xe partial pressure, while it is independent of the sustain voltage and the secondary-electrons-emission capability of protective layer. The unchanged average electron energy at the moment when the electric field becomes maximum confirms that the improvement of the VUV production efficiency mainly is attributed to the increase in electron heating efficiency of a PDP with high ion-induced secondary electrons emission protective layer. Combining the experimental and the simulation results, we conclude about the mechanism by which the VUV production is improved for the plasma display panel with a high Xe partial pressure and a cold cathode with high ion-induced secondary electrons emission.

Zhu, Di [School of Electronics and Information Engineering, Tianjin Polytechnic University, Tianjin (China); Song, Le, E-mail: songle@tju.edu.cn [State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin (China); Zhang, Xiong [School of Electronic Science and Engineering, Southeast University, Nanjing (China); Kajiyama, Hiroshi [Graduate School of Advanced Science of Matter, Hiroshima University, Higashi-hiroshima, Hiroshima (Japan)

2014-02-14T23:59:59.000Z

349

High pressure/high temperature vapor liquid equilibrium study of light gases in hydrogen-coal liquid model compound systems using perturbation chromatography  

SciTech Connect (OSTI)

Perturbation chromatography or gas-liquid partition chromatography (GLPC) provides a powerful tool for making physicochemical measurements. In this investigation GLPC was applied to study the vapor-liquid equilibrium behavior of light gases in nonvolatile coal liquid model compound solvents at high temperatures and high pressures. Improvements made in existing GLPC techniques include: the use of a high pressure tandem proportioning pump to give precise control of the carrier gas flow rate and low pressure drops; a high pressure ionization chamber to detect the injection of very dilute radioactive sample gases; and the use of a microcomputer to provide instantaneous integration and very precise retention times of the chromatographic peaks. Infinite dilution K-values for methane, ethane, propane, n-butane, carbon dioxide, and hydrogen sulfide in hydrogen-dibenzofuran systems were obtained at 100 and 125 C and up to 800 psia. Infinite dilution K-values for the same light gases in hydrogen-9-methylanthracene systems were obtained at 100, 125, 150, 175, and 200 C and up to 3000 psia. Henry's constants were determined for the light gases in 9-methylanthracene. Second cross virial coefficients and vapor phase infinite dilution fugacity coefficients were calculated for methane, ethane, propane, and n-butane in hydrogen. These results were combined with the experimental K-value measurements to obtain Henry's constants in hydrogen-9-methylanthracene mixtures of fixed liquid compositions. Infinite dilution heats of solution of the solute gases in the mixtures were calculated.

Kragas, T.K.

1983-01-01T23:59:59.000Z

350

The nonlinear anomalous lattice elasticity associated with the high-pressure phase transition in spodumene: A high precission static compression study  

E-Print Network [OSTI]

The high-pressure behavior of the lattice elasticity of spodumene, LiAlSi2O6, was studied by static compression in a diamond-anvil cell up to 9.3 GPa. Investigations by means of single-crystal XRD and Raman spectroscopy within the hydrostatic limits of the pressure medium focus on the pressure ranges around similar to 3.2 and similar to 7.7 GPa, which have been reported previously to comprise two independent structural phase transitions. While our measurements confirm the well-established first-order C2/c-P2(1)/c transformation at 3.19 GPa (with 1.2% volume discontinuity and a hysteresis between 0.02 and 0.06 GPa), both unit-cell dimensions and the spectral changes observed in high-pressure Raman spectra give no evidence for structural changes related to a second phase transition. Monoclinic lattice parameters and unit-cell volumes at in total 59 different pressure points have been used to re-calculate the lattice-related properties of spontaneous strain, volume strain, and the bulk moduli as a function of pr...

Ullrich, A; Miletich, R; 10.1007/s00269-009-0300-8

2010-01-01T23:59:59.000Z

351

Techno-economic feasibility study of providing variable frequency drive for high pressure pump, SWRO plant at NDDP, Kalpakkam  

Science Journals Connector (OSTI)

The cost of product water is a key factor in determination of acceptability of any desalination system and plant. In case of Sea Water Reverse Osmosis plants, most of the energy consumed is in the form of electricity. The High Pressure Pump (HPP) is the single major energy consuming equipment with a share of above 75%. Hence reduction in energy consumed by HPP will have a substantial effect on the overall energy consumption. The high starting torque requirement of high pressure pump results in increased acceleration time of the motor which subsequently increases the strain on the upstream electrical system from motor feeder to transformer. Provision of a Variable Frequency Drive can be a solution for both the above problems. This paper studies the techno-economic feasibility of providing variable frequency drive for HPP motor at NDDP, Kalpakkam.

R. Nagaraj; V. Murugan; Ashok Y. Dangore; K.L. Thalor; S. Prabakar; V.K. Srivastava; P.K. Tewari

2010-01-01T23:59:59.000Z

352

Soot particle sizing during high-pressure Diesel spray combustion via time-resolved laser-induced incandescence  

SciTech Connect (OSTI)

Single-pulse time-resolved laser-induced incandescence (TiRe-LII) signal transients from soot particulates were acquired during unsteady high pressure Diesel combustion in a constant volume cell for typical top dead center conditions during a Diesel engine cycle. Measurements were performed for initial gas pressures between 1 and 3 MPa, injection pressures between 50 and 130 MPa and laser probe timings between 5 and 16 ms after start of fuel injection. In separate experiments and for the same cell operating conditions gas temperatures were deduced from spectrally resolved soot pyrometry measurements. Implementing the LII model of Kock et al. [Combust. Flame 147 (2006) 79-92] ensemble mean soot particle diameters were evaluated from least-squares fitting of theoretical cooling curves to experimental TiRe-LII signal transients. Since in the experiments the environmental gas temperature and the width of an assumed particle size distribution were not known, the effects of the initial choice of these parameters on retrieved particle diameters were investigated. It is shown that evaluated mean particle diameters are only slightly biased by the choice of typical size distribution widths and gas temperatures. For a fixed combustion phase mean particle diameters are not much affected by gas pressure, however they become smaller at high fuel injection pressure. At a mean chamber pressure of 1.39 MPa evaluated mean particle diameters increased by a factor of two for probe delays between 5 and 16 ms after start of injection irrespective of the choices of first-guess fitting variables, indicating a certain robustness of data analysis procedure. (author)

Ryser, R.; Gerber, T.; Dreier, T. [Reaction Analysis Group, Department of General Energy, Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland)

2008-11-15T23:59:59.000Z

353

Soot particle sizing during high-pressure Diesel spray combustion via time-resolved laser-induced incandescence  

SciTech Connect (OSTI)

Single-pulse time-resolved laser-induced incandescence (TiRe-LII) signal transients from soot particulates were acquired during unsteady high pressure Diesel combustion in a constant volume cell for typical top dead center conditions during a Diesel engine cycle. Measurements were performed for initial gas pressures between 1 and 3 MPa, injection pressures between 50 and 130 MPa and laser probe timings between 5 and 16 ms after start of fuel injection. In separate experiments and for the same cell operating conditions gas temperatures were deduced from spectrally resolved soot pyrometry measurements. Implementing the LII model of Kock et al. [Combust. Flame 147 (20006) 79-92] ensemble mean soot particle diameters were evaluated from least-squares fitting of theoretical cooling curves to experimental TiRe-LII signal transients. Since in the experiments the environmental gas temperature and the width of an assumed particle size distribution were not known, the effects of the initial choice of these parameters on retrieved particle diameters were investigated. It is shown that evaluated mean particle diameters are only slightly biased by the choice of typical size distribution widths and gas temperatures. For a fixed combustion phase mean particle diameters are not much affected by gas pressure, however they become smaller at high fuel injection pressure. At a mean chamber pressure of 1.39 MPa evaluated mean particle diameters increased by a factor of two for probe delays between 5 and 16 ms after start of injection irrespective of the choices of first-guess fitting variables, indicating a certain robustness of data analysis procedure. (author)

Ryser, R.; Gerber, T.; Dreier, T. [Reaction Analysis Group, Department of General Energy, Paul Scherrer Institute, CH-5232 Villigen (Switzerland)

2009-01-15T23:59:59.000Z

354

Process for producing modified microorganisms for oil treatment at high temperatures, pressures and salinity  

DOE Patents [OSTI]

This invention relates to the preparation of new, modified organisms, through challenge growth processes, that are viable in the extreme temperature, pressure and pH conditions and salt concentrations of an oil reservoir and that are suitable for use in microbial enhanced oil recovery. The modified microorganisms of the present invention are used to enhance oil recovery and remove sulfur compounds and metals from the crude oil. The processes are comprised of steps which successively limit the carbon sources and increase the temperature, pressure and salinity of the media. This is done until microbial strains are obtained that are capable of growing in essentially crude oil as a carbon source and at a temperature range from about 70 C to 90 C, at a pressure range from about 2,000 to 2,500 psi and at a salinity range from about 1.3 to 35%. 68 figs.

Premuzic, E.T.; Lin, M.

1996-02-20T23:59:59.000Z

355

Inelastic X-ray scattering experiments on B[subscript 4]C under high static pressures  

SciTech Connect (OSTI)

Boron K-edge inelastic X-ray scattering experiments were performed on clean B{sub 4}C and shock impact recovered boron carbide up to 30 GPa and at ambient temperature to understand the pressure induced bonding changes. The spectral features corresponding to the boron site in the interlinking chain remained unchanged up to 30 GPa. The results of our experiments indicate that pressure induces less distortion to the boron sites and the local amorphization observed in the previous reports are due to the rearrangement of carbon atoms under extreme conditions without affecting the boron environment.

Kumar, Ravhi S.; Dandekar, Dattatraya; Leithe-Jasper, Andres; Tanaka, Takaho; Xiao, Yuming; Chow, Paul; Nicol, Malcolm F.; Cornelius, Andrew L. (UNLV); (MXPL-M); (CIW); (USARL)

2010-05-04T23:59:59.000Z

356

Single-Step Process for the Deposition of High Water Contact Angle and High Water Sliding Angle Surfaces by Atmospheric Pressure Dielectric Barrier Discharge  

Science Journals Connector (OSTI)

Single-Step Process for the Deposition of High Water Contact Angle and High Water Sliding Angle Surfaces by Atmospheric Pressure Dielectric Barrier Discharge ... The process used a high voltage alternating current (10?000 or 22?500 Hz) with a constant dissipated power of 100 W (1.1 W cm–2) generated by a Corona generator 7010R from SOFTAL electronic GmbH. ... high adhesion, presumably by generating large van der Waals' forces from the large surface area in very close contact with water. ...

Nicolas D. Boscher; David Duday; Stéphane Verdier; Patrick Choquet

2013-01-22T23:59:59.000Z

357

High-pressure late cycle direct injection of natural gas in a rail medium speed diesel engine  

SciTech Connect (OSTI)

The performance of an Electro-Motive Division (EMD) 567B, two-cylinder locomotive research engine, when operated on high-pressure/late-cycle injection of natural gas, is presented in this paper. A redesign and fabrication of the fuel system was undertaken to facilitate the consumption of natural gas. A small percentage of No.2 diesel fuel (DF-2) was used to ignite the natural gas. Engine performance, while running natural gas, resulted in matching rated speed and power with slightly lower thermal efficiency. Full power was achieved with a ratio of 99 percent natural gas and 1 percent diesel fuel. However, at high natural gas to diesel fuel ratios, audible knock was detected. The primary objective of the project was to establish technical feasibility of, and basic technology for, operating medium-speed rail diesel engines on high-pressure natural gas. Secondary objectives were to attain adequate engine performance levels for rail application, develop a system oriented toward retrofit of in-service locomotives, and realize any potential improvements in thermal efficiency due to use of the high-pressure/late-cycle approach.

Wakenell, J.F.; O'Neal, G.B.; Baker, Q.A.

1987-01-01T23:59:59.000Z

358

Manufacturing Cost Analysis of Novel Steel/Concrete Composite Vessel for Stationary Storage of High-Pressure Hydrogen  

SciTech Connect (OSTI)

A novel, low-cost, high-pressure, steel/concrete composite vessel (SCCV) technology for stationary storage of compressed gaseous hydrogen (CGH2) is currently under development at Oak Ridge National Laboratory (ORNL) sponsored by DOE s Fuel Cell Technologies (FCT) Program. The SCCV technology uses commodity materials including structural steels and concretes for achieving cost, durability and safety requirements. In particular, the hydrogen embrittlement of high-strength low-alloy steels, a major safety and durability issue for current industry-standard pressure vessel technology, is mitigated through the use of a unique layered steel shell structure. This report presents the cost analysis results of the novel SCCV technology. A high-fidelity cost analysis tool is developed, based on a detailed, bottom-up approach which takes into account the material and labor costs involved in each of the vessel manufacturing steps. A thorough cost study is performed to understand the SCCV cost as a function of the key vessel design parameters, including hydrogen pressure, vessel dimensions, and load-carrying ratio. The major conclusions include: The SCCV technology can meet the technical/cost targets set forth by DOE s FCT Program for FY2015 and FY2020 for all three pressure levels (i.e., 160, 430 and 860 bar) relevant to the hydrogen production and delivery infrastructure. Further vessel cost reduction can benefit from the development of advanced vessel fabrication technologies such as the highly automated friction stir welding (FSW). The ORNL-patented multi-layer, multi-pass FSW can not only reduce the amount of labor needed for assembling and welding the layered steel vessel, but also make it possible to use even higher strength steels for further cost reductions and improvement of vessel structural integrity. It is noted the cost analysis results demonstrate the significant cost advantage attainable by the SCCV technology for different pressure levels when compared to the industry-standard pressure vessel technology. The real-world performance data of SCCV under actual operating conditions is imperative for this new technology to be adopted by the hydrogen industry for stationary storage of CGH2. Therefore, the key technology development effort in FY13 and subsequent years will be focused on the fabrication and testing of SCCV mock-ups. The static loading and fatigue data will be generated in rigorous testing of these mock-ups. Successful tests are crucial to enabling the near-term impact of the developed storage technology on the CGH2 storage market, a critical component of the hydrogen production and delivery infrastructure. In particular, the SCCV has high potential for widespread deployment in hydrogen fueling stations.

Feng, Zhili [ORNL; Zhang, Wei [ORNL; Wang, Jy-An John [ORNL; Ren, Fei [ORNL

2012-09-01T23:59:59.000Z

359

Gait recognition: highly unique dynamic plantar pressure patterns among 104 individuals  

Science Journals Connector (OSTI)

...therefore unsurprising that dynamic foot pressure patterns, which indirectly...manually tuned for the right foot using 104-fold cross-validation...performance was verified on the left foot dataset and also with a separate...was selected to emphasize the power of automated dimensionality...

2012-01-01T23:59:59.000Z

360

High-pressure reaction and emissions characteristics of catalytic reactors for gas turbine combustors  

Science Journals Connector (OSTI)

The reaction and emissions characteristics of catalytic reactors comprising noble metal catalysts were investigated using homogeneous mixtures of natural gas and vitiated air at pressures up to 2.9 MPa. The mixture temperatures at inlet ranged from 500 to 700°C and the fuel-air ratio was increased till the exit gas temperature reached about 1200°C. Values of combustion efficiency greater than 99.5% and nitrogen oxides emissions for all catalytic reactors tested were less than 0.2 g NO2/kg fuel (2 ppm (15% 02) ) for all reactors at reactor exit gas temperatures higher than about 1100°C. Combustion efficiency decreased with increasing pressure in the heterogeneous-reaction controlled region, though a pressure increase favored homogeneous, gas phase reactions. Appreciable reactivity deterioration by aging for 1000 h at 1000°C was observed at lower mixture temperatures. A two-stage combustor comprising a conventional flame combustion stage and a catalytic stage was fabricated and its NO,x emissions and performance were evaluated at conditions typical of stationary gas turbine combustor operations. About 80% reduction in NO,x emissions levels compared with flame combustion was attained at 1 \\{MPa\\} pressure and 1180°C exit gas temperature, together with complete hydrocarbon combustion.

S. Hayashi; H. Yamada; K. Shimodaira

1995-01-01T23:59:59.000Z

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


361

Capabilities for measuring physical and chemical properties of rocks at high pressure  

SciTech Connect (OSTI)

The Experimental Geophysics Group of the Earth Sciences Department at Lawrence Livermore National Laboratory (LLNL) has experimental equipment that measures a variety of physical properties and phase equilibria and kinetics on rocks and minerals at extreme pressures (to 500 GPa) and temperatures (from 10 to 2800 K). These experimental capabilities are described in this report in terms of published results, photographs, and schematic diagrams.

Durham, W.B. (comp.)

1990-01-01T23:59:59.000Z

362

The Universe Viewed in Gamma-Rays 1 The Crab Nebula and Mkn 421 High-Energy Gamma-Ray  

E-Print Network [OSTI]

with a view to achieving a low energy threshold. Until October 2001 it used 40 heliostats (54 m2 each and the time distribution of the Cherenkov light pool as sampled by the heliostats. The corresponding event heliostat groups entering the trigger logic, and , the shower axis angle relative to the source direction

Enomoto, Ryoji

363

Effects of altitude and fuel oxygen content on the performance of a high pressure common rail diesel engine  

Science Journals Connector (OSTI)

Abstract The change of intake oxygen content caused by altitude variation and the change of fuel oxygen content both affect the performance of diesel engines. In this paper, comparative experiments were performed on a high pressure common rail diesel engine fueled with pure diesel and biodiesel–ethanol–diesel (abbreviated as BED) blends with oxygen content of 2%, 2.5%, and 3.2% in mass percentage at different atmospheric pressures of 81 kPa, 90 kPa, and 100 kPa. Moreover, in order to study the effect of different fuel blends with the same oxygen content on the performance of the diesel engine, tests were conducted on the diesel engine fueled with the BED blend and a biodiesel–diesel (abbreviated as BD) blend at 81 kPa ambient pressure. The experimental results indicate that the influence of altitude variation on the full-load engine brake torque is not significant when the pure diesel fuel is used. With the increase of BED fuel oxygen content, the engine brake torque reduces. When the pure diesel fuel is used, with the increase of atmospheric pressure, the brake specific fuel consumption (BSFC) decreases. As the fuel oxygen content increases, there is no significant difference in brake specific fuel consumption of the BED blends. And the values of brake specific energy consumption (BSEC) gradually decrease. Soot emissions of the diesel engine decrease with the increase of atmospheric pressure and fuel oxygen content. The effect of soot emission reduction by increasing the oxygen content of the fuel is more significant than the effect of increasing atmospheric pressure. The effects of BD and BED fuels with basically the same oxygen content on the full-load performance, fuel economy, and soot emissions of the diesel engine are different. The BSFC and soot emissions of the BED fuel are lower than those of the BD fuel.

Shaohua Liu; Lizhong Shen; Yuhua Bi; Jilin Lei

2014-01-01T23:59:59.000Z

364

Process for CO.sub.2 capture using zeolites from high pressure and moderate temperature gas streams  

DOE Patents [OSTI]

A method for separating CO.sub.2 from a gas stream comprised of CO.sub.2 and other gaseous constituents using a zeolite sorbent in a swing-adsorption process, producing a high temperature CO.sub.2 stream at a higher CO.sub.2 pressure than the input gas stream. The method utilizes CO.sub.2 desorption in a CO.sub.2 atmosphere and effectively integrates heat transfers for optimizes overall efficiency. H.sub.2O adsorption does not preclude effective operation of the sorbent. The cycle may be incorporated in an IGCC for efficient pre-combustion CO.sub.2 capture. A particular application operates on shifted syngas at a temperature exceeding 200.degree. C. and produces a dry CO.sub.2 stream at low temperature and high CO.sub.2 pressure, greatly reducing any compression energy requirements which may be subsequently required.

Siriwardane, Ranjani V. (Morgantown, WV); Stevens, Robert W. (Morgantown, WV)

2012-03-06T23:59:59.000Z

365

Energy dissipation via quantum-chemical hysteresis during high-pressure compression: A first-principles molecular dynamics study of phosphates  

E-Print Network [OSTI]

-phosphates (TPs) and zinc phosphates (ZPs) to changes in pressure p and temperature T is studied through firstEnergy dissipation via quantum-chemical hysteresis during high-pressure compression: A first to signifi- cant energy dissipation, which contributes to the high friction coefficients of ZP anti-wear pads

Mueser, Martin

366

Micro-structured electrode arrays:: high-frequency discharges at atmospheric pressure—characterization and new applications  

Science Journals Connector (OSTI)

Micro-structured electrode (MSE) arrays allow to generate large-area uniform glow discharges over a wide pressure range up to atmospheric pressure. The electrode dimensions in the ?m-range realized by means of modern micro-machining and galvanic techniques are small enough to generate sufficiently high electric field strengths to ignite gas discharges applying only moderate radio frequency (RF, 13.56 MHz) voltages (80–390 V in Ne, He, Ar and N2). The non-thermal plasma system is characterized by a special probe measuring the electric parameters. The MSE-driven plasmas show a different behavior from conventional discharge plasmas depending on the pressure and the type of gas. With the MSE arrays as plasma sources, several applications were developed and successfully tested: Plasma chemistry (decomposition of waste gases like CF4) and thin film deposition (e.g. SiO2 layers on various substrates). A new atmospheric pressure application realized in our lab is the sterilization of food packaging materials.

Lutz Baars-Hibbe; Christian Schrader; Philipp Sichler; Thorben Cordes; Karl-Heinz Gericke; Stephanus Büttgenbach; Siegfried Draeger

2004-01-01T23:59:59.000Z

367

CALE EOS form 2 fits for high pressure fused silica Hugoniot data  

SciTech Connect (OSTI)

The Hugoniot data on fused silica that are displayed on page 321 of the well-known volume ''LASL Shock Hugoniot Data, Stanley P. Marsh, Editor'' are fit to the EOS form 2 such as is used in CALE and other hydrocodes. Two fits are given: one to represent that data set over its full range (up to 84 GPa (840 kbar)) as well as a better fit for the pressure range below about 33 GPa (330 kbar). These EOSs have the strong point of being relatively simple for the user to implement and should be used to roughly represent the beyond-elastic response of fused silica in hydrocode simulations. They will not correctly reproduce the complex multiple-wave ramp-shock structure known to exist in fused silica at lower pressures.

Hare, D E; Managan, R A

2005-11-17T23:59:59.000Z

368

Evidence for plasma phase transition in high pressure hydrogen from ab-initio simulations  

SciTech Connect (OSTI)

We have performed a detailed study of molecular dissociation in liquid hydrogen using both Born-Oppenheimer molecular dynamics with Density Functional Theory and Coupled Electron-Ion Monte Carlo simulations. We observe a range of densities where (dP/d{rho}){sub T} = 0 that coincides with sharp discontinuities in the electronic conductivity, which is clear evidence of the plasma phase transition for temperatures 600K {le} T {le} 1500K. Both levels of theory exhibit the transition, although Quantum Monte Carlo predicts higher transition pressures. Based on the temperature dependence of the discontinuity in the electronic conductivity, we estimate the critical point of the transition at temperatures slightly below 2000 K. We examine the influence of proton zero point motion by using Path Integral Molecular Dynamics with Density Functional Theory; the main effect is to shift the transition to lower pressures. Furthermore, we calculate the melting curve of molecular hydrogen up to pressures of 200 GPa, finding a reentrant melting line in good agreement with previous calculations. The melting line crosses the metalization line at 700 K and 220 GPa using density functional energetics and at 550 K and 290 GPa using Quantum Monte Carlo energetics.

Morales, M; Pierleoni, C; Schwegler, E; Ceperley, D

2010-02-08T23:59:59.000Z

369

Experimental and modeling study of the effect of elevated pressure on lean high-hydrogen syngas flames  

Science Journals Connector (OSTI)

Abstract New laminar burning velocity measurements of 85:15% (by volume) H2–CO and H2–N2 mixtures with O2–He oxidizer are reported at lean conditions and elevated pressures (1–10 atm). Experiments are conducted using the heat flux method at initial temperature of 298 K. In this technique a near adiabatic flame is stabilized by balancing the heat loss from the flame to the burner with heat gain to the unburnt gas mixture such that no net heat loss to the burner is observed. A new facility was designed for such high pressure burner stabilized flame experiments. The results obtained are compared with five chemical kinetic schemes from literature for syngas mixtures at elevated pressures. Large differences are observed between the kinetic schemes and the experiments which can be attributed to certain key chemical reactions. A study of the kinetics is performed through reaction rate and sensitivity analysis which indicate that a high uncertainty still remains in important reactions that drive the production and consumption of species such as H, HO2 and OH. For lean mixtures the reaction H + O2(+M) = HO2(+M) contributes significantly to the deviation of models from the experiments. The present analysis in the lean mixture regime suggests the need for further studies in assessment and modification of rate constants for this reaction.

M. Goswami; J.G.H. van Griensven; R.J.M. Bastiaans; A.A. Konnov; L.P.H. de Goey

2014-01-01T23:59:59.000Z

370

Research and Development of High Temperature Light Water Cooled Reactor Operating at Supercritical-Pressure in Japan  

SciTech Connect (OSTI)

This paper summarizes the status and future plans of research and development of the high temperature light water cooled reactor operating at supercritical-pressure in Japan. It includes; the concept development; material for the fuel cladding; water chemistry under supercritical pressure; thermal hydraulics of supercritical fluid; and the conceptual design of core and plant system. Elements of concept development of the once-through coolant cycle reactor are described, which consists of fuel, core, reactor and plant system, stability and safety. Material studies include corrosion tests with supercritical water loops and simulated irradiation tests using a high-energy transmission electron microscope. Possibilities of oxide dispersion strengthening steels for the cladding material are studied. The water chemistry research includes radiolysis and kinetics of supercritical pressure water, influence of radiolysis and radiation damage on corrosion and behavior on the interface between water and material. The thermal hydraulic research includes heat transfer tests of single tube, single rod and three-rod bundles with a supercritical Freon loop and numerical simulations. The conceptual designs include core design with a three-dimensional core simulator and sub-channel analysis, and balance of plant. (authors)

Yoshiaki Oka [Nuclear Engineering Research Laboratory, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 112-0006 (Japan); Katsumi Yamada [Isogo Nuclear Engineering Center, Toshiba Corporation, 8, Shinsugita-cho, Isogo-ku, Yokohama, 235-8523 (Japan)

2004-07-01T23:59:59.000Z

371

High-Pressure Micellar Solutions of Polystyrene-block-Polybutadiene and Polystyrene-block-Polyisoprene Solutions in Propane Exhibit Cloud-Pressure Reduction and Distinct Micellization End Points  

SciTech Connect (OSTI)

Micellar solutions of polystyrene-block-polybutadiene and polystyrene-block-polyisoprene in propane are found to exhibit significantly lower cloud pressures than the corresponding hypothetical non-micellar solutions. Such a cloud-pressure reduction indicates the extent to which micelle formation enhances the apparent diblock solubility in near-critical and hence compressible propane. Pressure-temperature points beyond which no micelles can be formed, referred to as the micellization end points, are found to depend on the block type, size and ratio, and on the polymer concentration. For a given pressure, the micellization end-point temperature corresponds to the "critical micelle temperature." The cloud-pressure reduction and the micellization end point measured for styrene-diene diblocks in propane should be characteristic of all amphiphilic diblock copolymer solutions that form micelles in compressible solvents.

Winoto, Winoto [University of Wyoming, Laramie; Radosz, Maciej [University of Wyoming, Laramie; Tan, Sugata [University of Wyoming, Laramie; Hong, Kunlun [ORNL; Mays, Jimmy [ORNL

2009-01-01T23:59:59.000Z

372

'Devil's Staircase'-Type Phase Transition in NaV{sub 2}O{sub 5} under High Pressure  

SciTech Connect (OSTI)

The 'devil's staircase'-type phase transition in the quarter-filled spin-ladder compound NaV{sub 2}O {sub 5} has been discovered at low temperature and high pressure by synchrotron radiation x-ray diffraction. A large number of transitions are found to successively take place among higher-order commensurate phases with 2a x 2b x zc type superstructures. The observed temperature and pressure dependence of modulation wave number q{sub c}, defined by 1/z, is well reproduced by the axial next nearest neighbor Ising model. The q{sub c} is suggested to reflect atomic displacements presumably coupled with charge ordering in this system.

Ohwada, K.; Fujii, Y.; Takesue, N.; Isobe, M.; Ueda, Y.; Nakao, H.; Wakabayashi, Y.; Murakami, Y.; Ito, K.; Amemiya, Y. (and others)

2001-08-20T23:59:59.000Z

373

MICROSTRUCTURE AND MECHANICAL PROPERTY PERFORMANCE OF COMMERCIAL GRADE API PIPELINE STEELS IN HIGH PRESSURE GASEOUS HYDROGEN  

SciTech Connect (OSTI)

The continued growth of the world s developing countries has placed an ever increasing demand on traditional fossil fuel energy sources. This development has lead to increasing research and development of alternative energy sources. Hydrogen gas is one of the potential alternative energy sources under development. Currently the most economical method of transporting large quantities of hydrogen gas is through steel pipelines. It is well known that hydrogen embrittlement has the potential to degrade steel s mechanical properties when hydrogen migrates into the steel matrix. Consequently, the current pipeline infrastructure used in hydrogen transport is typically operated in a conservative fashion. This operational practice is not conducive to economical movement of significant volumes of hydrogen gas as an alternative to fossil fuels. The degradation of the mechanical properties of steels in hydrogen service is known to depend on the microstructure of the steel. Understanding the levels of mechanical property degradation of a given microstructure when exposed to hydrogen gas under pressure can be used to evaluate the suitability of the existing pipeline infrastructure for hydrogen service and guide alloy and microstructure design for new hydrogen pipeline infrastructure. To this end, the 2 Copyright 2010 by ASME microstructures of relevant steels and their mechanical properties in relevant gaseous hydrogen environments must be fully characterized to establish suitability for transporting hydrogen. A project to evaluate four commercially available pipeline steels alloy/microstructure performance in the presences of gaseous hydrogen has been funded by the US Department of Energy along with the private sector. The microstructures of four pipeline steels were characterized and then tensile testing was conducted in gaseous hydrogen and helium at pressures of 800, 1600 and 3000 psi. Based on measurements of reduction of area, two of the four steels that performed the best across the pressure range were selected for evaluation of fracture and fatigue performance in gaseous hydrogen at 800 and 3000 psi. This paper will describe the work performed on four commercially available pipeline steels in the presence of gaseous hydrogen at pressures relevant for transport in pipelines. Microstructures and mechanical property performances will be compared. In addition, recommendations for future work related to gaining a better understanding of steel pipeline performance in hydrogen service will be discussed.

Stalheim, Mr. Douglas [DGS Metallurgical Solutions Inc; Boggess, Todd [Secat; San Marchi, Chris [Sandia National Laboratories (SNL); Jansto, Steven [Reference Metals Company; Somerday, Dr. B [Sandia National Laboratories (SNL); Muralidharan, Govindarajan [ORNL; Sofronis, Prof. Petros [University of Illinois

2010-01-01T23:59:59.000Z

374

Synthesis of new Diamond-like B-C Phases under High Pressure and Temperatures  

SciTech Connect (OSTI)

A cubic BC3 (c-BC3) phase was synthesized by direct transformation from graphitic phases at a pressure of 39 GPa and temperature of 2200 K in a laser-heated diamond anvil cell (DAC). A combination of x-ray diffraction (XRD), electron diffraction (ED), transmission electron microscopy (TEM) imaging, and electron energy loss spectroscopy (EELS) measurements lead us to conclude that the obtained phase is hetero-nano-diamond, c-BC3. The EELS measurements show that the atoms inside the cubic structure are bonded by sp3 bonds.

Ming, L. C. [University of Hawaii] [University of Hawaii; Zinin, P. V. [University of Hawaii] [University of Hawaii; Sharma, S. K. [University of Hawaii] [University of Hawaii

2014-04-22T23:59:59.000Z

375

Pressure Wave Measurements from Thermal Cook-Off of an HMX Based High Explosive PBX 9501  

SciTech Connect (OSTI)

A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting pressure wave and how this wave propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.

Garcia, F; Forbes, J W; Tarver, C M; Urtiew, P A; Greenwood, D W; Vandersall, K S

2001-05-31T23:59:59.000Z

376

Pressure wave measurements from thermal cook-off of an HMX based high explosive  

SciTech Connect (OSTI)

A better understanding of thermal cook-off is important for safe handling and storing explosive devices. A number of safety issues exist about what occurs when a cased explosive thermally cooks off. For example, violence of the events as a function of confinement are important for predictions of collateral damage. This paper demonstrates how adjacent materials can be gauged to measure the resulting pressure wave and how this wave propagates in this adjacent material. The output pulse from the thermal cook-off explosive containing fixture is of obvious interest for assessing many scenarios.

Forbes, J W; Tarver, C M; Urtiew, P A; Garcia, F; Greenwood, D W; Vandersall, K S

2000-10-10T23:59:59.000Z

377

Effect of high pressure homogenization on the physical properties of milk  

E-Print Network [OSTI]

homogenization in milk with 3'to milk fat homogenized at 79. 5'C, . 14. Effect of homogenization pressure on fat globule size distribution using double stage homogenization in milk with 3' milk fat homogenized at 79. 5'C. . . . . 52 . . . . 54 . . . . 55... to protein mass ratio (FPM) increased, particularly when FPM & 6. Surface to volume 13 mean diameter increased from 0. 42+ . 02 p. m at FPM of 1, to 1. 85 + . 09 at FPM of 13. Increasing FPM by varying the fat content led to an increase in the specific...

Gonzalez De Cossio, Carlos

2012-06-07T23:59:59.000Z

378

The development and operational testing of an experimental reactor for gas-liquid-solid reaction systems at high temperatures and pressures  

E-Print Network [OSTI]

shaft. With the impeller in place and rotating, gas was drawn into the top port and ejected at the impeller mount. The reactor pressure was monitored via the transducer port. The transducer was a Viatran Pressure Transducer, model 103. The liquid...THE DEVELOPMENT AND OPERATIONAL TESTING OF AN EXPERIMENTAL REACTOR FOR GAS-LIQUID-SOLID REACTION SYSTEMS AT HIGH TEMPERATURES AND PRESSURES A Thesis by RICHARD KENNETH HESS Submitted to the Graduate College of Texas A&M University in partial...

Hess, Richard Kenneth

2012-06-07T23:59:59.000Z

379

High-pressure storage of hydrogen fuel: ammonia borane and its related compounds  

Science Journals Connector (OSTI)

As a promising candidate material for hydrogen storage, ammonia borane (NH3BH3) has attracted significant interest in recent years due to its remarkably high hydrogen content. Subjecting this material to high pre...

Yu Lin; Wendy L. Mao

2014-09-01T23:59:59.000Z

380

High-Energy Forming of Monolithic and Powder Materials by Pressure  

Science Journals Connector (OSTI)

Well-established and new processes for the high-energy shaping of materials are analyzed along with the equipment they ... attention is given to the latest methods of high-energy compaction of metallic and nonmet...

M. N. Samodurova; L. A. Barkov; V. A. Ivanov; B. A. Yarov

2013-07-01T23:59:59.000Z

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


381

Small-volume, ultrahigh-vacuum-compatible high-pressure reaction cell for combined kinetic and in situ IR spectroscopic measurements on planar model catalysts  

SciTech Connect (OSTI)

We describe the design and performance of a high-pressure reaction cell for simultaneous kinetic and in situ infrared reflection (IR) spectroscopic measurements on model catalysts at elevated pressures, between 10{sup -3} and 10{sup 3} mbars, which can be operated both as batch reactor and as flow reactor with defined gas flow. The cell is attached to an ultrahigh-vacuum (UHV) system, which is used for sample preparation and also contains facilities for sample characterization. Specific for this design is the combination of a small cell volume, which allows kinetic measurements with high sensitivity under batch or continuous flow conditions, the complete isolation of the cell from the UHV part during UHV measurements, continuous temperature control during both UHV and high-pressure operation, and rapid transfer between UHV and high-pressure stage. Gas dosing is performed by a designed gas-handling system, which allows operation as flow reactor with calibrated gas flows at adjustable pressures. To study the kinetics of reactions on the model catalysts, a quadrupole mass spectrometer is connected to the high-pressure cell. IR measurements are possible in situ by polarization-modulation infrared reflection-absorption spectroscopy, which also allows measurements at elevated pressures. The performance of the setup is demonstrated by test measurements on the kinetics for CO oxidation and the CO adsorption on a Au/TiO{sub 2}/Ru(0001) model catalyst film at 1-50 mbar total pressure.

Zhao, Z.; Diemant, T.; Haering, T.; Rauscher, H.; Behm, R.J. [Department Surface Chemistry and Catalysis, University of Ulm, D-89069 Ulm (Germany)

2005-12-15T23:59:59.000Z

382

Hydrate risks and prevention solutions for a high pressure gas field offshore in South China Sea  

Science Journals Connector (OSTI)

YC13-4 gas field is located in the west of the South China Sea, where the seawater depth is around 90 m, and the average surface temperature is 26.2°C, while the minimum temperature at seabed is 18.9°C. Subsea wellheads are designed for gas production. In this paper, the risks of hydrate formation during drilling, well testing and gas production are analysed under different operation conditions. The results show that most hydrate problems will occur during shutdown and restart operations, and the degree of hydrate occurrence is slight to medium, which poses difficult tasks for choosing safe, reliable and economic methods to mitigate the hydrate problems. Various solutions for hydrate control in different processes are considered, including filling the wellbore with drilling/completion fluids or seawater for pressure control during shutdowns, and injection of methanol into wellbore and subsea pipeline during production. A simple and economic method using down-hole chokes to reduce gas pressure before it enters the hydrate stability zone is introduced, and the placement depth of the down-hole choke is determined. [Received: September 5, 2012; Accepted: March 6, 2013

Liang Zhang; Anyuan Huang; Wei Wang; Shaoran Ren; Shukai Jin; Dake Fang

2013-01-01T23:59:59.000Z

383

Author's personal copy Crystal structure and compressibility of a high-pressure Ti-rich oxide,  

E-Print Network [OSTI]

promising candidate for the development of electrolytes in solid oxide fuel cells. & 2009 Elsevier Ltd. All for solid-oxide-fuel-cell electrolytes, owing to its excellent stability at high temperature, good, solid electrolytes in high-temperature fuel cells, thermal barrier coatings in engines, and high

Downs, Robert T.

384

Control of a fluid particle under simulated deep-ocean conditions in a high-pressure water tunnel  

Science Journals Connector (OSTI)

An apparatus that permits the observation of liquid C O 2 particles in a simulated deep-ocean environment was designed modeled constructed and tested. Analysis concerning the vertical stability and control of the fluid particle in a countercurrent flow loop is presented. The vertical position of the particle was found to vary due to the gradual dissolution of the C O 2 into the water and various other random effects. Using linearized equations for spherical particle motion in the fluid flow a second-order dynamic equation is derived and analyzed. The servocontrol system consists of a video system that digitizes particle position in a viewing window and a centrifugal pump that can control the speed of the countercurrent flow in order to maintain the particle within the observation window of a charge-coupled devicecamera. Currently the system is being used to obtain information on the dissolution behavior of C O 2 in seawater at various conditions of pressure and temperature that simulate ocean depths down to 3400 m . This information can be used to predict the fate of C O 2 drops in the ocean whether released from natural seeps leaks from suboceanic geologic C O 2 storage sites or from engineered deep-ocean injection systems. The study of other liquids and gases is also possible.

Igor V. Haljasmaa; Jeffrey S. Vipperman; Ronald J. Lynn; Robert P. Warzinski

2005-01-01T23:59:59.000Z

385

High-pressure/high-temperature gas-solubility study in hydrogen-phenanthrene and methane-phenanthrene systems using static and chromatographic techniques  

SciTech Connect (OSTI)

The design and discovery of sources for alternative energy such as coal liquefaction has become of major importance over the past two decades. One of the major problems in such design in the lack of available data, particularly, for gas solubility in polycyclic aromatics at high temperature and pressure. Static and gas-liquid partition chromatographic methods were used for the study of hydrogen-phenanthrene and methane-phenanthrene systems. The static data for these two binaries were taken along 398.2, 423.2, 448.2, and 473.2 K isotherms up to 25.23 MPa. Gas-liquid partition chromatography was used to study the infinite dilution behavior of methane, ethane, propane, n-butane, and carbon dioxide in the hydrogen-phenanthrene system as well as hydrogen, ethane, n-butane, and carbon dioxide in the methane-phenanthrene binary. The principle objective was to examine the role of the elution gas. Temperatures were along the same isotherms as the static data and up to 20.77 MPa. With the exception of carbon dioxide, Henry's constants were calculated for all systems. Expressions for the heat of solution as a function of pressure were derived for both binary and chromatographic data. Estimates of delta H/sub i/sup sol/ at high pressure were presented.

Malone, P.V.

1987-01-01T23:59:59.000Z

386

Anisotropic yielding of rocks at high temperatures and pressures; Annual Progress Report, 1988-1989  

SciTech Connect (OSTI)

The experimental results we have obtained on Four-Mile gneiss have demonstrated that the yield behavior of quartzo-feldspathic rocks containing only a small percentage (10%) of mica can be markedly anisotropic, provided the mica minerals exhibit a strong crystallographic preferred orientation. Samples of gneiss oriented such that resolved shear stresses on the foliation plane are large are considerably weaker than granites of similar grain size and composition, and this weakness is attributed to enhanced nucleation of microcracks in quartz and feldspar adjacent to mica grains that are suitably oriented for slip. We expect the yield behavior of rocks containing a higher proportion of phyllosilicates to be influenced by the strongly anisotropic nature of these minerals as well, although the strengths, temperature and pressure dependencies, and flow-controlling mechanisms in such rocks may be significantly different.

Kronenberg, A.K.; Russell, J.E.; Carter, N.L.

1989-11-30T23:59:59.000Z

387

Pressure Dependence of High?Frequency Sound Attenuation in the Deep Pacific Ocean  

Science Journals Connector (OSTI)

Vertical and horizontal acoustic paths located in the Pacific Ocean between depths of 910 and 3350 m have been utilized to determine the attenuation of sound at a nominal frequency of 75 kHz. Results from these two different geometries show that predicted values exceed the observed magnitudes of acoustic attenuation at this frequency and at these depths. At 3350 m the predicted value is 22.7 dB/km vs a measured value of 13.3±0.5 dB/km a discrepancy of more than 9 dB. Furthermore increasing pressure reduces the attenuation a fact which supports the work of Fisher [J. Acoust. Soc. Amer. 38 805 (1965)] in contrast to that of Kester and Pytkowicz [Geochimica et Cosmochimica Acta 34 1039 (1970)]. However the amount of reduction is larger than previously suspected by more than 80% [This paper represents results of research sponsored by the Office of Naval Research.

H. F. Bezdek

1972-01-01T23:59:59.000Z

388

Nuclear Quantum Effects and Nonlocal Exchange-Correlation Functionals Applied to Liquid Hydrogen at High Pressure  

Science Journals Connector (OSTI)

Using first-principles molecular dynamics, we study the influence of nuclear quantum effects (NQEs) and nonlocal exchange-correlation density functionals (DFs) near molecular dissociation in liquid hydrogen. NQEs strongly influence intramolecular properties, such as bond stability, and are thus an essential part of the dissociation process. Moreover, by including DFs that account for either the self-interaction error or dispersion interactions, we find a much better description of molecular dissociation and metallization than previous studies based on classical protons and/or local or semilocal DFs. We obtain excellent agreement with experimentally measured optical properties along Hugoniot curves for precompressed states, and while we still find a first-order liquid-liquid transition at low temperatures, transition pressures are increased by more than 100 GPa.

Miguel A. Morales, Jeffrey M. McMahon, Carlo Pierleoni, and David M. Ceperley

2013-02-05T23:59:59.000Z

389

High Pressure Pulse Radiolysis-Reduction Cyt c by Ru(II) Complexes  

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

for a for a Reversible Intermolecular Electron-Transfer Reaction involving Isonicotinamide(pentaammine)ruthenium and Cytochrome c Beate Bänsch, Martin Meier, Pablo Martinez, Rudi van Eldik, Chang Su, Ji Sun, Stephan S. Isied and James F. Wishart Inorg. Chem. 33, 4744-4749 (1994) Abstract: The reversible intermolecular electron-transfer reaction between pentaammineisonicotinamideruthenium(II/III) and horse-heart cytochrome c iron(III/II) was subjected to a detailed kinetic and thermodynamic study as a function of temperature and pressure. Theoretical calculations based on the Marcus-Hush theory were employed to predict all rate and equilibrium constants as well as activation parameters. There is an excellent agreement between the kinetically and thermodynamically determined equilibrium

390

Film Cooling Performance in a Transonic High-pressure Vane: Decoupled Simulation and Conjugate Heat Transfer Analysis  

Science Journals Connector (OSTI)

Abstract The continuous demand for increased performance and reliability of gas turbines leads to the improvement of prediction tools. Having regard to the effects of heat transfer on the residual life of gas turbine components, it is necessary to achieve a high level of accuracy in the evaluation of thermal loads. Computational fluid dynamics is able to provide reliable data in a limited lapse of time. In this paper, the numerical analysis of the cooled vane of the MT1 high-pressure turbine stage is presented. A grid dependence analysis based on the evaluation of the aero-thermal characteristics of the vane has been performed. Turbulence is modeled using the kT-kL-? method whose performance in this kind of configuration is rarely debated in the scientific literature. Model parameters have been tuned to match the experimental data. The final objective of the present activity is to assess the capability of numerical methods to deal with an annular, transonic high-pressure vane with a realistic film cooling configuration. Adiabatic effectiveness, heat transfer coefficient and net heat flux reduction distributions have been evaluated, the latter providing relevant information on the performance of the cooling system. The coupled fluid-solid simulation of the cooled configuration has also been performed to evaluate the impact of conjugate heat transfer on the prediction of thermal loads. Results show a non-negligible difference in the wall temperature evaluation between the decoupled and the coupled approach, mainly caused by the heat conduction in the solid.

Massimiliano Insinna; Duccio Griffini; Simone Salvadori; Francesco Martelli

2014-01-01T23:59:59.000Z

391

Gram-scale separation of curium from americium using alpha-hydroxyisobutyric acid in high-pressure cation columns  

SciTech Connect (OSTI)

Quantities of heavy element (americium and curium) up to 2.3 g have been successfully separated by chromatographic elution from cation resin using alpha-hydroxyisobutyrate in equipment originally designed for decigram-scale separations of /sup 252/Cf and heavier elements. The high-pressure ion exchange process was reliable and relatively easy to operate. Overall curium recoveries of 80 to 90% were readily achieved with decontamination from americium by factors of 400 to 500. The product and waste streams are both in forms readily coupled to further processing steps.

Bigelow, J.E.; Benker, D.E.; Chattin, F.R.; King, L.J.; Knauer, J.B.; Ross, R.G.; Stacy, R.G.; Wiggins, J.T.

1984-01-01T23:59:59.000Z

392

Thermodynamics of the ferromagnetic phase transition in nearly half metallic CoS2 at high pressures  

SciTech Connect (OSTI)

The volume change and heat capacity at the ferromagnetic phase transition in COS2 were measured at high pressures using X-rays generated by the Argonne synchrotron light source and by ac-calorimetry, respectively. The transition entropy, calculated on the basis of these experimental data, drops along the transition line due to quantum degradation, as required by Nernst's law. The volume change increases strongly along the transition line, which is explained by specifics of the compressibility difference of coexisting phases that results from nearly half metallic nature of the ferromagnetic phase of COS2. (C) 2013 Elsevier Ltd. All rights reserved.

Elkin, F. S. [Institute for High Pressure Physics of Russian Academy of Sciences; Zibrov, I. P. [Institute for High Pressure Physics of Russian Academy of Sciences; Novikov, A. P. [Institute for High Pressure Physics of Russian Academy of Sciences; Khasanov, S. S. [Institute for Solid State Physics Russian Academy of Sciences; Sidorov, V. A. [Institute for High Pressure Physics of Russian Academy of Sciences; Petrova, A. E. [Institute for High Pressure Physics of Russian Academy of Sciences; Lograsso, Thomas A. [Ames Laboratory; Thompson, J. D. [Los Alamos National Laboratory; Stishov, S. M. [Institute for High Pressure Physics of Russian Academy of Sciences

2013-12-06T23:59:59.000Z

393

Quantum Monte Carlo Simulation of the High-Pressure Molecular-Atomic Crossover in Fluid Hydrogen  

Science Journals Connector (OSTI)

A first-order liquid-liquid phase transition in high-pressure hydrogen between molecular and atomic fluid phases has been predicted in computer simulations using ab initio molecular dynamics approaches. However, experiments indicate that molecular dissociation may occur through a continuous crossover rather than a first-order transition. Here we study the nature of molecular dissociation in fluid hydrogen using an alternative simulation technique in which electronic correlation is computed within quantum Monte Carlo methods, the so-called coupled electron-ion Monte Carlo method. We find no evidence for a first-order liquid-liquid phase transition.

Kris T. Delaney; Carlo Pierleoni; D. M. Ceperley

2006-12-06T23:59:59.000Z

394

Experimental study on the effects of high/low pressure EGR proportion in a passenger car diesel engine  

Science Journals Connector (OSTI)

Abstract An experimental study was conducted to investigate the effects of the proportion between high pressure and low pressure exhaust gas recirculation (HP/LP EGR) on engine operation. The study focused on the characteristics of combustion, emissions, and fuel consumption in a 2.2 L passenger car diesel engine. The experiments were performed under three part-load and steady-state operating conditions. The LP EGR portion was swept from 0 to 1, while the mass flow rate of fresh air and boost pressure were fixed. The results showed that the intake manifold temperature decreased gradually as the LP EGR portion increased due to its greater cooling capability by a longer supply line and an intercooler. However, the required cooling power for the intercooler increased because the LP EGR gas, which has a higher temperature than the fresh air, was induced upstream of the compressor. The lowered intake manifold temperature with the increase of the LP EGR portion led to the prolonged ignition delay of pilot injections, which resulted in a slightly higher peak heat release rate in the main combustion. A higher LP EGR portion showed a lower fuel consumption level than the HP EGR only case because the variable geometry turbocharger (VGT) nozzle opened more widely to maintain the boost pressure, which means a lower pumping loss. Nitrogen oxide (NOx) emissions were also decreased as the LP EGR portion increased due to lowered intake charge temperature. Consequently, it was possible to improve the trade-off relationship between \\{NOx\\} emissions and fuel consumption with the increase of the LP EGR portion under steady-state operating conditions.

Youngsoo Park; Choongsik Bae

2014-01-01T23:59:59.000Z

395

High-temperature high-pressure phases of lithium from electron force field (eFF) quantum electron dynamics simulations  

Science Journals Connector (OSTI)

...high temperatures (20,000–2,000,000 K) characteristic of deep interiors of giant planets (1), conditions of thermonuclear fusion, and phenomena generated by shocks from planetary impact (2). New methods for experimental study of these regimes...

Hyungjun Kim; Julius T. Su; William A. Goddard III

2011-01-01T23:59:59.000Z

396

Studies of the mechanism of Coal Hydrogenation by Electron Spin Resonance. Quarterly technical progress report, March 1-May 31, 1980. [For high-temperature, high pressure measurements  

SciTech Connect (OSTI)

This is the first quarterly report on the program Studies of Coal Hydrogenation by Electron Spin Resonance. This quarter has been devoted to constructing apparatus for high temperature-high pressure electron paramagnetic resonance (EPR) measurements, characterizing the performance of the microwave cavity, and carrying out preliminary room temperature studies on coals and coal products. At the start of this program, there were no microwave cavities available to study high pressure-high temperature reactions. A system was constructed which can be used to study coal hydrogenation, and satisfies the conditions described in the report. This cavity was constructed using funding from Rockwell International, and will be used on this program. Because of the dependence of the work to be done with this device for this program, the construction is described in detail. This report, therefore, considers the design philosophy, construction of the device, a preliminary discussion of its performance, and application of the cavity for room temperature studies on several varieties of coal.

Goldberg, Ira B.

1980-07-01T23:59:59.000Z

397

Pressure induced high spin-low spin transition in FeSe superconductor studied by x-ray emission spectroscopy and ab initio calculations  

SciTech Connect (OSTI)

FeSe is a simple binary system in the iron based superconducting family and exhibits a significant pressure induced increase in the superconducting transition temperature (T{sub c}). In addition to pressure effect, spin fluctuations, magnetic ordering, and crystal structure all play vital roles in altering T{sub c}. Even though various experiments and theoretical simulations explain the connection among them and superconductivity, the interplay between these important parameters is still not clearly understood. Here, we report the pressure effect on the spin state of Fe in FeSe superconductor studied using synchrotron x-ray emission spectroscopy at ambient and low temperatures down to 8 K near T{sub c}. Pressure induced high spin to low spin transition was observed at both ambient and low temperatures with continuous suppression of Fe magnetic moments under increasing pressure. The spin transition is closely related to the pressure induced tetragonal to orthorhombic structural transition.

Kumar, Ravhi S.; Zhang, Yi; Xiao, Yuming; Baker, Jason; Cornelius, Andrew; Veeramalai, Sathishkumar; Chow, Paul; Chen, Changfeng; Zhao, Yusheng (UNLV); (CIW)

2011-09-20T23:59:59.000Z

398

Next Generation Pressurized Oxy-Coal Combustion: High Efficiency and No Flue Gas Recirculation  

SciTech Connect (OSTI)

The Gas Technology Institute (GTI) has developed a pressurized oxy-coal fired molten bed boiler (MBB) concept, in which coal and oxygen are fired directly into a bed of molten coal slag through burners located on the bottom of the boiler and fired upward. Circulation of heat by the molten slag eliminates the need for a flue gas recirculation loop and provides excellent heat transfer to steam tubes in the boiler walls. Advantages of the MBB technology over other boilers include higher efficiency (from eliminating flue gas recirculation), a smaller and less expensive boiler, modular design leading to direct scalability, decreased fines carryover and handling costs, smaller exhaust duct size, and smaller emissions control equipment sizes. The objective of this project was to conduct techno-economic analyses and an engineering design of the MBB project and to support this work with thermodynamic analyses and oxy-coal burner testing. Techno-economic analyses of GTI’s pressurized oxy-coal fired MBB technology found that the overall plant with compressed CO2 has an efficiency of 31.6%. This is a significant increase over calculated 29.2% efficiency of first generation oxy-coal plants. Cost of electricity (COE) for the pressurized MBB supercritical steam power plant with CO2 capture and compression was calculated to be 134% of the COE for an air-coal supercritical steam power plant with no CO2 capture. This compares positively with a calculated COE for first generation oxy-coal supercritical steam power plants with CO2 capture and compression of 164%. The COE for the MBB power plant is found to meet the U.S. Department of Energy (DOE) target of 135%, before any plant optimization. The MBB power plant was also determined to be simpler than other oxy-coal power plants with a 17% lower capital cost. No other known combustion technology can produce higher efficiencies or lower COE when CO2 capture and compression are included. A thermodynamic enthalpy and exergy analysis found a number of modifications and adjustments that could provide higher efficiency and better use of available work. Conclusions from this analysis will help guide the analyses and CFD modeling in future process development. The MBB technology has the potential to be a disruptive technology that will enable coal combustion power plants to be built and operated in a cost effective way, cleanly with no carbon dioxide emissions. A large amount of work is needed to quantify and confirm the great promise of the MBB technology. A Phase 2 proposal was submitted to DOE and other sponsors to address the most critical MBB process technical gaps. The Phase 2 proposal was not accepted for current DOE support.

Rue, David

2013-09-30T23:59:59.000Z

399

Study on Sub-sea Pipelines Hyperbaric Welding Repair under High Air Pressures  

Science Journals Connector (OSTI)

Most Chinese sub-sea pipelines are buried in Bohai Sea less than ... are widely used For the application of offshore pipelines repair, the hyperbaric TIG welding process under high...

Canfeng Zhou; Xiangdong Jiao; Long Xue…

2011-01-01T23:59:59.000Z

400

In situ X-ray observations of the decomposition of brucite and the graphite–diamond conversion in aqueous fluid at high pressure and temperature  

Science Journals Connector (OSTI)

...?An experimental technique to make real-time observations at high pressure and temperature of the diamond-forming process in candidate material of mantle fluids as a catalyst has been established for the first...

T. Okada; W. Utsumi; H. Kaneko; M. Yamakata…

2002-08-01T23:59:59.000Z

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


401

Effect of Ultra High Pressure Under Argon and Temperature on the Volatiles and Piperine Content and Microbiological Quality of Black Pepper (Piper Nigrum L.)  

Science Journals Connector (OSTI)

In the search of effective decontamination methods of herbal spices, combined action of high pressure under argon at various temperatures has been applied. Ground black pepper (Piper nigrum L.) samples were expos...

S. Sk?pska; B. Windyga; E. Kostrzewa…

2003-01-01T23:59:59.000Z

402

Experimental determination of bulk modulus of 14 A tobermorite using high pressure synchrotron X-ray diffraction  

SciTech Connect (OSTI)

Using a diamond anvil cell, 14 A tobermorite, a structural analogue of calcium silicate hydrates (C-S-H), was examined by high-pressure synchrotron X-ray diffraction up to 4.8 GPa under hydrostatic conditions. The bulk modulus of 14 A tobermorite was calculated, K{sub o} = 47 GPa. Comparison of the current results with previous high pressure studies on C-S-H(I) indicates that: (1) the compression behavior of the lattice parameters a and b of 14 A tobermorite and C-S-H(I) are very similar, implying that both materials may have very similar Ca-O layers, and also implying that an introduction of structural defects into the Ca-O layers may not substantially change in-plane incompressibility of the ab plane of 14 A tobermorite; and (2) the bulk modulus values of 14 A tobermorite and C-S-H(I) are dominated by the incompressibility of the lattice parameter c, which is directly related to the interlayer spacing composed of dreierketten silicate chains, interlayer Ca, and water molecules.

Oh, Jae Eun [Department of Civil and Environmental Engineering, University of California, Berkeley, 94720, CA USA (United States); School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology, Ulsan Metropolitan City, 689-798 (Korea, Republic of); Clark, Simon M. [Department of Earth and Planetary Sciences, Maquarie University, Sydney, NSW 2109 (Australia); Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, 20015, CA (United States); Wenk, Hans-Rudolf [Department of Earth and Planetary Sciences, Maquarie University, Sydney, NSW 2109 (Australia); Monteiro, Paulo J.M., E-mail: monteiro@berkeley.edu [Department of Civil and Environmental Engineering, University of California, Berkeley, 94720, CA USA (United States)

2012-02-15T23:59:59.000Z

403

Modeling high-pressure adsorption of gas mixtures on activated carbon and coal using a simplified local-density model  

SciTech Connect (OSTI)

The simplified local-density (SLD) theory was investigated regarding its ability to provide accurate representations and predictions of high-pressure supercritical adsorption isotherms encountered in coalbed methane (CBM) recovery and CO{sub 2} sequestration. Attention was focused on the ability of the SLD theory to predict mixed-gas adsorption solely on the basis of information from pure gas isotherms using a modified Peng-Robinson (PR) equation of state (EOS). An extensive set of high-pressure adsorption measurements was used in this evaluation. These measurements included pure and binary mixture adsorption measurements for several gas compositions up to 14 MPa for Calgon F-400 activated carbon and three water-moistened coals. Also included were ternary measurements for the activated carbon and one coal. For the adsorption of methane, nitrogen, and CO{sub 2} on dry activated carbon, the SLD-PR can predict the component mixture adsorption within about 2.2 times the experimental uncertainty on average solely on the basis of pure-component adsorption isotherms. For the adsorption of methane, nitrogen, and CO{sub 2} on two of the three wet coals, the SLD-PR model can predict the component adsorption within the experimental uncertainties on average for all feed fractions (nominally molar compositions of 20/80, 40/60, 60/40, and 80/20) of the three binary gas mixture combinations, although predictions for some specific feed fractions are outside of their experimental uncertainties.

Fitzgerald, J.E.; Robinson, R.L.; Gasem, K.A.M. [Oklahoma State University, Stillwater, OK (United States). School of Chemical Engineering

2006-11-07T23:59:59.000Z

404

A combustion/deposition entrained reactor for high?temperature/pressure studies of coal and coal minerals  

Science Journals Connector (OSTI)

The combustion of coal and coal?derived fuels in heat engines poses significant technical challenges in terms of establishing high combustion rates and efficiencies controlling emissions and minimizing the impact of fuel contaminants on engine components. An entrained reactor has been designed and constructed to study coal particle combustion the tendency of coal ash to form deposits on heat engine components and the effects of fuel additives on residual ash composition. The reactor is designed for high temperature/pressure conditions similar to those of a coal?fired gas turbine. Optical access ports and advanced instrumentation allow the i n s i t u measurement of gas and particle temperatures and vapor phase alkali concentrations. The reactor has been used to study the deposition potential of several coals as a function of process conditions and to determine the effects of selected additives on the deposition rate.

Rodney J. Anderson; Ronald G. Logan; Charles T. Meyer; Richard A. Dennis

1990-01-01T23:59:59.000Z

405

Low refractive index silicon oxide coatings at room temperature using atmospheric-pressure very high-frequency plasma  

Science Journals Connector (OSTI)

Low refractive index silicon oxide films were deposited using atmospheric-pressure He/SiH4/CO2 plasma excited by a 150-MHz very high-frequency power. Significant increase in deposition rate at room temperature could prevent the formation of dense SiO2 network, decreasing refractive index of the resulting film effectively. As a result, a silicon oxide film with the lowest refractive index, n = 1.24 at 632.8 nm, was obtained with a very high deposition rate of 235 nm/s. The reflectance and transmittance spectra showed that the low refractive index film functioned as a quarter-wave anti-reflection coating of a glass substrate.

H. Kakiuchi; H. Ohmi; Y. Yamaguchi; K. Nakamura; K. Yasutake

2010-01-01T23:59:59.000Z

406

Plasma diagnostics of low pressure high power impulse magnetron sputtering assisted by electron cyclotron wave resonance plasma  

SciTech Connect (OSTI)

This paper reports on an investigation of the hybrid pulsed sputtering source based on the combination of electron cyclotron wave resonance (ECWR) inductively coupled plasma and high power impulse magnetron sputtering (HiPIMS) of a Ti target. The plasma source, operated in an Ar atmosphere at a very low pressure of 0.03 Pa, provides plasma where the major fraction of sputtered particles is ionized. It was found that ECWR assistance increases the electron temperature during the HiPIMS pulse. The discharge current and electron density can achieve their stable maximum 10 {mu}s after the onset of the HiPIMS pulse. Further, a high concentration of double charged Ti{sup ++} with energies of up to 160 eV was detected. All of these facts were verified experimentally by time-resolved emission spectroscopy, retarding field analyzer measurement, Langmuir probe, and energy-resolved mass spectrometry.

Stranak, Vitezslav [Ernst-Moritz-Arndt-Universitaet Greifswald, Institut fuer Physik, Felix-Hausdorff-Str. 6, 17489 Greifswald (Germany); University of South Bohemia, Institute of Physics and Biophysics, Branisovska 31, 370 05 Ceske Budejovice (Czech Republic); Herrendorf, Ann-Pierra; Drache, Steffen; Bogdanowicz, Robert; Hippler, Rainer [Ernst-Moritz-Arndt-Universitaet Greifswald, Institut fuer Physik, Felix-Hausdorff-Str. 6, 17489 Greifswald (Germany); Cada, Martin; Hubicka, Zdenek [Institute of Physics v. v. i., Academy of Science of the Czech Republic, Na Slovance 2, 182 21 Prague (Czech Republic); Tichy, Milan [Charles University in Prague, Faculty of Mathematics and Physics, V Holesovickach 2, 180 00 Prague (Czech Republic)

2012-11-01T23:59:59.000Z

407

Ultra-High Pressure Driver and Nozzle Survivability in the RDHWT/MARIAH II Hypersonic Wind Tunnel  

SciTech Connect (OSTI)

An ultra-high pressure device provides a high enthalpy (> 2500 kJ/kg), low entropy (< 5 kJ/kg-K) air source for the RDHWT/MARIAH II Program Medium Scale Hypersonic Wind Tunnel. The design uses stagnation conditions of 2300 MPa (330,000 Psi) and 750 K (900 F) in a radial configuration of intensifiers around an axial manifold to deliver pure air at 100 kg/s mass flow rates for run times suitable for aerodynamic, combustion, and test and evaluation applications. Helium injection upstream of the nozzle throat reduces the throat wall recovery temperature to about 1200 K and reduces the oxygen concentration at the nozzle wall.

Costantino, M.; Brown, G.; Raman, K.; Miles, R.; Felderman, J.

2000-06-02T23:59:59.000Z

408

The Results From the First High-Pressure Melt Ejection Test Completed in the Molten Fuel Moderator Interaction Facility at Chalk River Laboratories  

SciTech Connect (OSTI)

A high-pressure melt ejection test using prototypical corium was conducted at Atomic Energy of Canada Limited Chalk River Laboratories. This test was planned by the CANDU Owners Group to study the potential for an energetic interaction between molten fuel and water under postulated single-channel flow-blockage events. The experiments were designed to address regulator concerns surrounding this very low probability postulated accident events in CANDU Pressurized Heavy Water Reactors. The objective of the experimental program is to determine whether a highly energetic 'steam explosion' and associated high-pressure pulse, is possible when molten material is finely fragmented as it is ejected from a fuel channel into the heavy-water moderator. The finely fragmented melt particles would transfer energy to the moderator as it is dispersed, creating a modest pressure pulse in the calandria vessel. The high-pressure melt ejection test consisted of heating up a {approx} 5 kg thermite mixture of U, U{sub 3}O{sub 8}, Zr, and CrO{sub 3} inside a 1.14-m length of insulated pressure tube. When the molten material reached the desired temperature of {approx} 2400 deg C, the pressure inside the tube was raised to 11.6 MPa, failing the pressure tube at a pre-machined flaw, and releasing the molten material into the surrounding tank of 68 deg C water. The experiment investigated the dynamic pressure history, debris size, and the effects of the material interacting with tubes representing neighbouring fuel channels. The measured mean particle size was 0.686 mm and the peak dynamic pressures were between 2.54 and 4.36 MPa, indicating that an energetic interaction between the melt and the water did not occur in the test. (authors)

Nitheanandan, T.; Kyle, G.; O'Connor, R.; Sanderson, DB. [Chalk River Laboratories, Atomic Energy of Canada Limited, Chalk River, Ontario, Canada, K0J 1J0 (Canada)

2006-07-01T23:59:59.000Z

409

Organic vapor separation: Process design with regards to high-flux membranes and the dependence on real gas behavior at high pressure applications  

SciTech Connect (OSTI)

High-flux membranes are well-suited for separating organic vapor from air. There are many applications for organic vapor recovery at tank farms. Here, the membrane technology is already considered as state of the art. However, new applications operating at higher pressures, e.g., water and hydrocarbon dewpointing of natural gas, real gas behavior, and the so-called concentration polarization effect have to be taken into account. Experimental investigations have been carried out and the results are presented. The performance of a membrane module is calculated considering real gas behavior.

Alpers, A.; Keil, B.; Luedtke, O.; Ohlrogge, K.

1999-10-01T23:59:59.000Z

410

Probing of bonding changes in B[subscript 2]O[subscript 3] glasses at high pressure with inelastic X-ray scattering  

SciTech Connect (OSTI)

Full understanding of atomic arrangement in amorphous oxides both at ambient and high pressure is an ongoing fundamental puzzle. Whereas the structures of archetypal oxide glasses such as v-B{sub 2}O{sub 3} at high pressure are essential to elucidate origins of anomalous macroscopic properties of more complex melts, knowledge of the high-pressure structure and pressure-induced coordination changes of these glasses has remained elusive due to lack of suitable in situ experimental probes. Here, we report synchrotron inelastic X-ray scattering results for v-{sub 2}O{sub 3} at pressures up to 22.5 GPa, revealing the nature of pressure-induced bonding changes and the structure. Direct in situ measurements show a continuous transformation from tri-coordinated to tetra-coordinated boron beginning at 4-7 GPa with most of the boron tetra-coordinated above 20 GPa, forming dense tetrahedral v-B{sub 2}O{sub 3}. After decompression from high pressure the bonding reverts back to tri-coordinated boron but with the data suggesting a permanent densification.

Lee, Sung Kuen; Eng, Peter J.; Mao, Ho-Kwang; Meng, Yue; Newville, Matthew; Hu, Michael Y.; Shu, Jinfu (Seoul); (CIW); (UC)

2010-07-19T23:59:59.000Z

411

RESEARCH ARTICLE Quantitative X-ray measurements of high-pressure fuel sprays  

E-Print Network [OSTI]

in the STAR-CD software. 1 Introduction Diesel engines have been the preferred power train for heavy heavy duty diesel injector A. I. Rami´rez � S. Som � Suresh K. Aggarwal � A. L. Kastengren � E. M. El in the near-nozzle region of a diesel engine injector. The technique provides high spatial and temporal

Aggarwal, Suresh K.

412

HIGH PRESSURE VAPOR TRANSPORT OF ZnGeP 2 : II. THREEDIMENSIONAL SIMULATION OF GASDYNAMICS UNDER  

E-Print Network [OSTI]

grant #DMS­9201252. 2 To appear in the proceedings of the International Symposium on Experimental for Research in Scientific Computation Department of Mathematics North Carolina State University Raleigh, NC Carolina State University Raleigh, NC, USA Abstract The fluid dynamics in a vertical reactor for high

413

High-pressure alloying of potassium and iron: Radioactivity in the Earth's core?  

E-Print Network [OSTI]

/U (potassium/uranium) ratios of $1 Ã? 104 on Earth are distinct from the 8 Ã? 104 ratio found in chondrites argued that because potassium is a moderately volatile element, it is depleted due to the high for the depletion of K in the terrestrial planets, as a mass-dependent depletion of the isotopes would

Lee, Kanani K. M.

414

Pressure-induced valence change in YbAl3: A combined high-pressure inelastic x-ray scattering and theoretical investigation  

E-Print Network [OSTI]

4Los Alamos National Laboratory, P.O. Box 1663, Los Alamos, New Mexico 87545, USA 5 HPCAT, Carnegie-ray emission RXES measurements were performed on the intermediate-valence com- pound YbAl3 under pressure of up-liquid coherence and the crossover to the local-moment regime have been studied by transport,15 inelastic nuclear

Svane, Axel Torstein

415

Experimental Investigation of Magnetic Superconducting, and other Phase Transitions in Novel f-Electron Materials at Ultra-high Pressures Using Designer Diamond Anvils  

SciTech Connect (OSTI)

Pressure is a powerful control parameter, owing to its ability to affect crystal and electronic structure without introducing defects, for the investigation of condensed matter systems. Some f-electron, heavy-fermion materials display interesting and novel behavior when exposed to pressures achievable with conventional experimental techniques; however, a growing number of condensed matter systems require extreme conditions such as ultrahigh pressures, high magnetic fields, and ultralow temperatures to sufficiently explore the important properties. To that end, we have been funded to develop an ultrahigh pressure facility at the University of California, San Diego (UCSD) in order to investigate superconductivity, magnetism, non-Fermi liquid behavior, and other phenomena under extreme conditions. Our goals for the second year of this grant were as follows: (a) perform electrical resistivity measurements on novel samples at a myriad of pressures using conventional piston-cylinder techniques, Bridgman anvil techniques, and diamond anvil cell technology; (b) install, commission, and operate an Oxford Kelvinox MX-100 dilution refrigerator for access to ultralow temperatures and high magnetic fields. (c) continue the development of diamond anvil cell (DAC) technology. During the past year, we have successfully installed the Oxford Kelvinox MX-100 dilution refrigerator and verified its operability down to 12 mK. We have begun an experimental program to systematically investigate the f-electron compound URu2Si2 under pressure and in the presence of magnetic fields. We have also continued our collaborative work with Sam Weir at Lawrence Livermore National Laboratory (LLNL) on Au4V and implemented a new corollary study on Au1-xVx using ultrahigh pressures. We have continued developing our DAC facility by designing and constructing an apparatus for in situ pressure measurement as well as designing high pressure cells. This report serves to highlight the progress we have made towards developing an ultrahigh pressure research facility at UCSD, the research performed in the past year, as well as future directions we plan to pursue.

Maple, M. Brian

2005-09-13T23:59:59.000Z

416

Solid-Liquid and Solid-Solid Transformations in the Rare-Earth Metals at High Pressures  

Science Journals Connector (OSTI)

The fusion behavior and solid-solid transformations in the rare-earth metals have been investigated at pressures in the range 6-65 kbar. The phase diagrams are presented for La, Pr, Nd, Sm, Gd, and Tb. The initial melting slopes of Dy to Lu have been obtained. Since most of the rare-earth (R.E.) metals melt from a bcc structure, they offer a series for comparison. When the initial melting slope is plotted against atomic number they fall into groups according to their valency; the typically divalent metals Eu and Yb in one, and the typically trivalent metals La, Gd, and Lu in another. Samarium and the metals from Tb to Tm have melting slopes which are intermediate between those of the typically divalent and trivalent metals. It is suggested that these metals assume a partial divalent character in the liquid state and possibly also in the bcc phase. This suggestion derives support from the fact that the gaseous neutral atoms of the R.E. elements, with the exception of La, Gd, and Lu, have no 5d electron and are therefore divalent. Cerium exhibits a unique fusion behavior and its negative melting slope has been attributed to the tetravalency (4f?5d electron promotion) of the atoms in the liquid. For the very small melting slope of Pr, it is suggested that the atoms in the liquid have partial tetravalent character due to 4f?5d electron promotion. Comparisons with alkali metals are made and it is deduced that the R.E. metals are quite compressible at high temperatures. Pressure induced transformations in the rare-earth metals are in the sequence hcp?Sm-type?double hcp?fcc. A plausible mechanism based on the variation of ca ratio with pressure is discussed for hcp?Sm-type transformation.

A. Jayaraman

1965-08-02T23:59:59.000Z

417

Laser-driven formation of a high-pressure phase in amorphous silica  

SciTech Connect (OSTI)

A combination of electron diffraction and infrared reflectance measurements shows that synthetic silica transforms partially into stishovite under high-intensity (GW/cm2) laser irradiation, probably by the formation of a dense ionized plasma above the silica surface. During the transformation the silicon coordination changes from four-fold to six-fold and the silicon-oxygen bond changes from mostly covalent to mostly ionic, such that optical properties of the transformed material differ significantly from those of the original glass. This phase transformation offers one suitable mechanism by which laser-induced damage grows catastrophically once initiated, thereby dramatically shortening the service lifetime of optics used for high-power photonics applications such as inertial confinement fusion.

Salleo, Alberto; Taylor, Seth T.; Martin, Michael C.; Panero, Wendy R.; Jeanloz, Raymond; Genin, Francois Y.; Sands, Timothy

2002-05-31T23:59:59.000Z

418

Qualitative and quantitative analysis of low molecular weight phenols by high pressure liquid chromatography  

E-Print Network [OSTI]

. A. , Bethany College Chairman of Advisory Comnittee: Dr. Lloyd W. Rooney A high performance liquid chromatographic (HPI C) method was de- veloped for the separation and identification of substituted benzoic and cinnamic acids (phenolic acids...). The 8 commonly occurring phenolic acids chosen as standards were: gallic, protocatechuic, p-hydroxyben- zoic, vanillic, caffeic, p-coumaric, feruli c and ci nnami c acids. Separation was on a nonpolar C18 substituted, silica based column with elution...

Hahn, David Henry

2012-06-07T23:59:59.000Z

419

Local structure around rare-earth ions in B{sub 2}O{sub 3} glass at high pressure  

SciTech Connect (OSTI)

Melt quenching of B{sub 2}O{sub 3} with less than 25 mol. % rare-earth oxide (RE{sub 2}O{sub 3}) at ambient pressure results in a milky white glass because of liquid-liquid phase separation into B{sub 2}O{sub 3} and RE{sub 2}O{sub 3}{center_dot}3B{sub 2}O phases. In contrast, we have found that melt quenching under GPa-order pressure realizes a transparent RE-doped B{sub 2}O{sub 3} glass. This study investigates the local structure around the RE ions in the B{sub 2}O{sub 3} glass prepared at 3 GPa using optical measurements and electron-spin-echo envelope modulation spectroscopy. It is shown that the RE-rich microparticles disappear and the RE ions are isolated from each other in a highly symmetric crystal field formed by triangular and tetrahedral boron units. This result is consistent with that extrapolated from the data for RE-doped sodium borate glasses.

Funabiki, Fuji [Frontier Research Center, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503 (Japan)] [Frontier Research Center, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503 (Japan); Matsuishi, Satoru [Research Center for Strategic Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503 (Japan)] [Research Center for Strategic Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503 (Japan); Hosono, Hideo [Frontier Research Center, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503 (Japan) [Frontier Research Center, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503 (Japan); Research Center for Strategic Materials, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503 (Japan); Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Yokohama, 226-8503 (Japan)

2013-06-14T23:59:59.000Z

420

Study of high pressure gas filled RF cavities for muon collider  

E-Print Network [OSTI]

Muon collider is a considerable candidate of the next-generation high-energy lepton collider machine. Operating an RF cavity in a multi-Tesla magnet is a critical requirement in a muon accelerator and a cooling channel. However, the maximum RF gradient in a vacuum RF cavity is strongly limited by an external magnetic field. Dense hydrogen gas filled RF cavity has been proposed since it is functional of generating a high RF accelerating gradient in a strong magnetic field and making an ionization cooling process at the same time. A critical issue of the cavity is a beam- induced plasma that consumes a considerable amount of RF power. The gas filled RF test cell was made and measured the RF loading due to a beam-induced plasma by using an intense proton beam at Fermilab. By doping an electronegative gas in dense hydrogen, the plasma loading effect is significantly mitigated. The result shows that the cavity is functional with a muon collider beam. Recent progress is shown in this presentation.

Yonehara, Katsuya

2015-01-01T23:59:59.000Z

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


421

High T/sub c/ superconducting films of Y-Ba-Cu oxide prepared by low-pressure plasma spraying  

SciTech Connect (OSTI)

A low-pressure plasma spraying technique for depositing high T/sub c/ Y-Ba-Cu-O thick films has been developed. Films with a thickness range of 20--100 ..mu..m have been prepared by using Y/sub 0.3/Ba/sub 0.7/CuO/sub x/ powders. After post-annealing in oxygen for 1 h at 950 /sup 0/C, the films, which were deposited on a nimonic alloy substrate heated at 650 /sup 0/C during spraying, exhibited a zero resistance temperature of 90.6 K with a transition width (90%--10%) of 2 K and a critical current density (77 K, 0 T) of 690 A/cm/sup 2/.

Tachikawa, K.; Watanabe, I.; Kosuge, S.; Kabasawa, M.; Suzuki, T.; Matsuda, Y.; Shinbo, Y.

1988-03-21T23:59:59.000Z

422

Assessment of Computer Simulation Software and Process Data for High Pressure Die Casting of Magnesium  

SciTech Connect (OSTI)

Computer software for the numerical simulation of solidification and mold filling is an effective design tool for cast structural automotive magnesium components. A review of commercial software capabilities and their validation procedures was conducted. Aside form the software assessment, the program addressed five main areas: lubricant degradation, lubricant application, gate atomization, and heat transfer at metal mold interfaces. A test stand for lubricant application was designed. A sensor was used for the direct measurement of heat fluxes during lubricant application and casting solidification in graphite molds. Spray experiments were conducted using pure deionized water and commercial die lubricants. The results show that the sensor can be used with confidence for measuring heat fluxes under conditions specific to the die lube application. The data on heat flux was presented in forms suitable for use in HPDC simulation software. Severe jet breakup and atomization phenomena are likely to occur due to high gate velocities in HPDC. As a result of gate atomization, droplet flow affects the mold filling pattern, air entrapment, skin formation, and ensuing defects. Warm water analogue dies were designed for obtaining experimental data on mold filling phenomena. Data on break-up jet length, break-up pattern, velocities, and droplet size distribution were obtained experimentally and was used to develop correlations for jet break-up phenomena specific to die casting gate configurations.

Sabau, Adrian S [ORNL; Hatfield, Edward C [ORNL; Dinwiddie, Ralph Barton [ORNL; Kuwana, Kazunori [University of Kentucky; Viti, Valerio [University of Kentucky, Lexington; Hassan, Mohamed I [University of Kentucky, Lexington; Saito, Kozo [University of Kentucky

2007-09-01T23:59:59.000Z

423

The analysis of cracks in high-pressure piping and their effects on strength and lifetime of construction components at the Ignalina nuclear plant  

SciTech Connect (OSTI)

A number of cracks and damages of other sorts have been identified in the high-pressure parts at the Ignalina Nuclear Plant. They are caused by inadequate production- and repair technologies, as well as by thermal, chemical and mechanical processes of their performance. Several techniques are available as predictions of cracks and other defects of pressurized vessels. The choice of an experimental technique should be based on the level of its agreement with the actual processes.

Aleev, A.; Petkevicius, K.; Senkus, V. [and others

1997-04-01T23:59:59.000Z

424

Three-dimensional discrete ordinates radiation transport calculations of neutron fluxes for beginning-of-cycle at several pressure vessel surveillance positions in the high flux isotope reactor  

SciTech Connect (OSTI)

The objective of this research was to determine improved thermal, epithermal, and fast fluxes and several responses at mechanical test surveillance location keys 2, 4, 5, and 7 of the pressure vessel of the Oak Ridge National Laboratory High Flux Isotope Reactor (HFIR) for the beginning of the fuel cycle. The purpose of the research was to provide essential flux data in support of radiation embrittlement studies of the pressure vessel shell and beam tubes at some of the important locations.

Pace, J.V. III; Slater, C.O.; Smith, M.S.

1993-11-01T23:59:59.000Z

425

Phase transitions and equation of state of CsI under high pressure and the development of a focusing system for x-rays  

SciTech Connect (OSTI)

The phase transitions and equation of state of ionic solid cesium iodide were studied under high pressure and room temperature in a diamond anvil cell. The studies were carried out using both energy dispersive and angular dispersive diffraction methods on synchrotron radiation sources over the pressure range from atmospheric pressure to over 300 gigapascals (3 million atmospheres). CsI undergoes a distinct phase transition at about 40 GPa, a pressure that is much lower than the reported insulator-metal transition at 110 GPa, from the atmospheric pressure B2(CsCl) structure to an orthorhombic structure. At higher pressures, a continuous distortion in the structure was observed with a final structure similar to a hcp lattice under ultra high pressure. No volume discontinuity was observed at the insulator-metal transition. The newly found transition sequence is different from the result of previous static compression studies. The current structure has a smaller unit cell volume than the previous assignment. This has resolved a long existing controversy among the previous static compression studies, the dynamic compression studies, and the theoretical studies. The current results also explain the apparent discrepancy between the present study and the previous static studies. We also present the development of a focusing system for high energy x-rays (> 12 keV) that is particularly suited for high pressure diffraction studies. This system uses a pair of multilayer coated spherical mirrors in a Kirkpatrick-Baez geometry. A focused beam size less than 10 micron in diameter can be readily achieved with sufficient intensity to perform diffraction studies. 93 refs., 46 figs., 15 tabs.

Wu, Yan.

1990-11-01T23:59:59.000Z

426

Investigation on the effects of ultra-high pressure and temperature on the rheological properties of oil-based drilling fluids  

E-Print Network [OSTI]

Designing a fit-for-purpose drilling fluid for high-pressure, high-temperature (HP/HT) operations is one of the greatest technological challenges facing the oil and gas industry today. Typically, a drilling fluid is subjected to increasing...

Ibeh, Chijioke Stanley

2009-05-15T23:59:59.000Z

427

Effect of High-Pressure Impregnation on Structure Variation and Desulfurization Property of a Zn-Based Sorbent Prepared Using Lignite as a Support  

Science Journals Connector (OSTI)

Effect of High-Pressure Impregnation on Structure Variation and Desulfurization Property of a Zn-Based Sorbent Prepared Using Lignite as a Support ... Lignite reserves are relatively abundant in China; however, its utilization is significantly limited because of its high water content and low calorific value. ...

Xiurong Ren; Qiang He; Yurong Dong; Meijun Wang; Liping Chang; Weiren Bao

2014-06-10T23:59:59.000Z

428

Anatomy of the AGN in NGC 5548: III. The high-energy view with NuSTAR and INTEGRAL  

E-Print Network [OSTI]

We describe the analysis of the seven broad-band X-ray continuum observations of the archetypal Seyfert 1 galaxy NGC 5548 that were obtained with XMM-Newton or Chandra, simultaneously with high-energy (> 10 keV) observations with NuSTAR and INTEGRAL. These data were obtained as part of a multiwavelength campaign undertaken from the summer of 2013 till early 2014. We find evidence of a high-energy cut-off in at least one observation, which we attribute to thermal Comptonization, and a constant reflected component that is likely due to neutral material at least a few light months away from the continuum source. We confirm the presence of strong, partial covering X-ray absorption as the explanation for the sharp decrease in flux through the soft X-ray band. The obscurers appear to be variable in column density and covering fraction on time scales as short as weeks. A fit of the average spectrum over the range 0.3-400 keV with a realistic Comptonization model indicates the presence of a hot corona with a temperat...

Ursini, F; Petrucci, P -O; Matt, G; Cappi, M; Bianchi, S; Kaastra, J; Harrison, F; Walton, D J; di Gesu, L; Costantini, E; De Marco, B; Kriss, G A; Mehdipour, M; Paltani, S; Peterson, B M; Ponti, G; Steenbrugge, K C

2015-01-01T23:59:59.000Z

429

Fluid-to-fluid scaling for convective heat transfer in tubes at supercritical and high subcritical pressures  

Science Journals Connector (OSTI)

Abstract Following a review of two recent sets of fluid-to-fluid scaling laws for supercritical heat transfer and a discussion of their possible limitations, we have proposed two additional sets of scaling laws, which take into account empirically adjustable versions of the Dittus–Boelter correlation and which are applicable to both the supercritical and the high subcritical flow regions. We have compiled a database of heat transfer measurements in carbon dioxide flowing upwards in vertical heated tubes that are free of deterioration or enhancement. We then applied the four sets of scaling laws to these data to compute values of the water-equivalent heat transfer coefficient and compared these values to predictions of a transcritical look-up table, which was earlier shown to represent well a large compilation of measurements in water at supercritical and high subcritical pressures. It was shown that the two earlier methods systematically overestimated the heat transfer coefficient in water and also introduced significant imprecision. In contrast, the two proposed methods of scaling introduce no bias and have lower precision uncertainties than those of the previous scaling methods.

H. Zahlan; D.C. Groeneveld; S. Tavoularis

2014-01-01T23:59:59.000Z

430

Formation of carbonaceous nano-layers under high interfacial pressures during lubrication with mineral and bio-based oils  

SciTech Connect (OSTI)

In order to better protect steel surfaces against wear under high loads, understanding of chemical reactions between lubricants and metal at high interfacial pressures and elevated temperatures needs to be improved. Solutions at 5 to 20 wt. % of zinc di-2-ethylhexyl dithio phosphate (ZDDP) and chlorinated paraffins (CP) in inhibited paraffinic mineral oil (IPMO) and inhibited soy bean oil (ISBO) were compared on a Twist Compression Tribotester (TCT) at 200 MPa. Microscopy of wear tracks after 10 seconds tribotesting showed much smoother surface profiles than those of unworn areas. X-ray photoelectron spectroscopy (XPS) coupled with Ar-ion sputtering demonstrated that additive solutions in ISBO formed 2–3 times thicker carbon-containing nano-layers compared to IPMO. The amounts of Cl, S or P were unexpectedly low and detectable only on the top surface with less than 5 nm penetration. CP blends in IPMO formed more inorganic chlorides than those in ISBO. It can be concluded that base oils are primarily responsible for the thickness of carbonaceous nano-layers during early stages of severe boundary lubrication, while CP or ZDDP additive contributions are important, but less significant.

Baltrus, John P. [U.S. DOE

2014-01-01T23:59:59.000Z

431

Pressure transducer  

DOE Patents [OSTI]

A pressure transducer suitable for use in high temperature environments includes two pairs of induction coils, each pair being bifilarly wound together, and each pair of coils connected as opposite arms of a four arm circuit; an electrically conductive target moveably positioned between the coil pairs and connected to a diaphragm such that deflection of the diaphragm causes axial movement of the target and an unbalance in the bridge output.

Anderson, Thomas T. (Downers Grove, IL); Roop, Conard J. (Lockport, IL); Schmidt, Kenneth J. (Midlothian, IL); Gunchin, Elmer R. (Lockport, IL)

1989-01-01T23:59:59.000Z

432

Development of Larger Diameter High Pressure CNG Cylinder Manufactured by Piercing and Drawing for Natural Gas Vehicle  

Broader source: Energy.gov [DOE]

These slides were presented at the International Hydrogen Fuel and Pressure Vessel Forum on September 27 – 29, 2010, in Beijing, China.

433

News and Views  

Science Journals Connector (OSTI)

... and so an accelerated service and more stations were required. Transformers are used at the substations to step down the high pressure power to rotary converters which transform the alternating into ... uniform and furnish a reserve of power, a battery of accumulators is installed at each substation. The machines and switchgear at the ...

1931-05-23T23:59:59.000Z

434

Electrical resistance and magnetic properties of the neptunium monopnictides NpAs, NpSb, and NpBi at high pressures  

Science Journals Connector (OSTI)

We report on high-pressure studies performed on the neptunium pnictides NpAs and NpBi via electrical resistance up to ?25 GPa between 1.3 K and room temperature, and on a high-pressure investigation up to 9 GPa and at 4.2 K on NpSb using 237Np Mössbauer spectroscopy. This work extends previous high-pressure studies carried out on NpAs via Mössbauer spectroscopy, on NpSb via resistance, and on all pnictides via x-ray study. In NpX (X=As,Sb,Bi) crystallizing in the cubic-NaCl phase the ground state is antiferromagnetic and displays a noncollinear 3k spin structure. The strong increase of the resistivity with decreasing temperature observed in the temperature range of the 3k order at ambient pressure collapses at 0.23 (NpAs), 2.7 (NpSb), and 3.9 GPa (NpBi). No significant change of the hyperfine interactions is found in NpAs or NpSb at the pressure where the resistance collapse is observed. The Kondo anomaly of the resistivity observed at ambient pressure disappears above 25 GPa (NpAs), 2.7 GPa (NpSb), and 3 GPa (NpBi). The Néel temperature TN of all compounds and the ordered moment of NpAs and NpSb decrease with reduced volume. For NpAs and NpBi the resistance indicates the presence of magnetic order at least up to 16 GPa. The compounds undergo a pressure-induced structural transition with a volume reduction by ?10%. Although in the resistance of NpSb the signature of magnetic order is lost already at 8 GPa in the high-pressure phase, a magnetic hyperfine field is present, which is reduced by ?30% relative to the NaCl phase. It is suggested that the resistance collapse is caused by a change of the magnetic structure, that the decrease of TN is due to a modification of the Fermi surface besides a small 5f delocalization, and that in NpSb the volume reduction in the structural high-pressure phase leads to an enhanced 5f delocalization.

V. Ichas; S. Zwirner; D. Braithwaite; J. C. Spirlet; J. Rebizant; W. Potzel

1997-12-01T23:59:59.000Z

435

Standard practice for evaluation of disbonding of bimetallic stainless alloy/steel plate for use in high-pressure, high-temperature refinery hydrogen service  

E-Print Network [OSTI]

1.1 This practice covers a procedure for the evaluation of disbonding of bimetallic stainless alloy/steel plate for use in refinery high-pressure/high-temperature (HP/HT) gaseous hydrogen service. It includes procedures to (1) produce suitable laboratory test specimens, (2) obtain hydrogen charging conditions in the laboratory that are similar to those found in refinery HP/HT hydrogen gas service for evaluation of bimetallic specimens exposed to these environments, and (3) perform analysis of the test data. The purpose of this practice is to allow for comparison of data among test laboratories on the resistance of bimetallic stainless alloy/steels to hydrogen-induced disbonding (HID). 1.2 This practice applies primarily to bimetallic products fabricated by weld overlay of stainless alloy onto a steel substrate. Most of the information developed using this practice has been obtained for such materials. The procedures described herein, may also be appropriate for evaluation of hot roll bonded, explosive bonded...

American Society for Testing and Materials. Philadelphia

2001-01-01T23:59:59.000Z

436

The high pressure synthesis and structure of a new aurate, CaAu{sub 2}O{sub 4}  

SciTech Connect (OSTI)

A novel aurate CaAu{sub 2}O{sub 4} has been synthesized by high pressure-temperature technique. The sample was contained in an Au capsule and heated to 1000{approximately}1200{degrees}C at 12{approximately}15 GPa in the split-sphere multi-anvil apparatus (USSA-2000). Electron probe Microanalysis of small crystals indicated an oxide ratio of 0.96(6) CaO:1.01(2) Au{sub 2}O{sub 3}. The compound is pale yellow, with a = 5.991141(1), c = 10.04983(3) {angstrom}, Z = 4, 14{sub 1}/a. The structure was solved using both synchroton x-ray powder diffraction and single crystal x-ray data. It consists of corner-linked AuO{sub 4} square planes and distorted CaO{sub 8} dodecahedra; in the figure Ca{sup 2+} ions (circles) are filled in the cavities surrounded by staggered square planar AuO{sub 4} units.

Park, J.H.; Parise, J.B. [State Univ. of New York, Stony Brook, NY (United States)

1995-12-31T23:59:59.000Z

437

Transformation pathways in high-pressure solid nitrogen: from molecular N$_2$ to polymeric cg-N  

E-Print Network [OSTI]

The transition pathway in high-pressure solid nitrogen from N$_2$ molecular state to polymeric cg-N phase was investigated by means of \\textit{ab initio} molecular dynamics and metadynamics simulations. In our study, we observed a transformation mechanism from molecular $Immm$ phase initiated by formation of $trans$-$cis$ chains. These chains further connected within layers and formed a chain-planar state, which we describe as a mixture of crystalline $trans$-$cis$ chain phase and $planar$ phase (both with $Pnma$ symmetry). This form appeared in molecular dynamics performed at 120 GPa and 1500 K and also in metadynamics run at 110 GPa and 1500 K, in which the chains continued to reorganize further and finally formed cg-N. During various other metadynamics runs, two different phases emerged - molecular $P2_1/c$ and two-three-coordinated chain-like $Cm$. The transformation mechanism leading to cg-N may be characterized as a progressive polymerization process passing throughout several intermediate states of var...

Plašienka, Dusan

2014-01-01T23:59:59.000Z

438

Measurement of critical energy for direct initiation of spherical detonations in stoichiometric high-pressure H{sub 2}-O{sub 2} mixtures  

SciTech Connect (OSTI)

In this study, the critical energy for direct initiation of spherical detonations in stoichiometric high-pressure hydrogen-oxygen mixtures are measured and investigated to look at the effect of explosion limits on the detonation sensitivity. Results up to an initial pressure of 20 atm are obtained. Experiments are carried out in a spherical bomb and direct initiation is achieved via spark ignition from a high-voltage capacitor discharge. A detailed description of different methods to obtain a good estimate of the correct amount of energy deposited into the mixture used to initiate the detonation, including the calorimeter method and current method, is provided. It is demonstrated that at elevated initial pressure, the second explosion limit effect plays a significant role leading to slow-branching reactions and the detonation sensitivity of hydrogen mixtures is comparable to other common hydrocarbon mixtures at such condition. (author)

Kamenskihs, Vsevolods; Lee, John H.S. [Department of Mechanical Engineering, McGill University, Montreal, Quebec (Canada); Ng, Hoi Dick [Department of Mechanical and Industrial Engineering, Concordia University, Montreal, Quebec (Canada)

2010-09-15T23:59:59.000Z

439

High-pressure synthesis and crystal structure of the lithium borate HP-LiB{sub 3}O{sub 5}  

SciTech Connect (OSTI)

The new lithium borate HP-LiB{sub 3}O{sub 5} was synthesized under high-pressure/high-temperature conditions of 6 GPa and 1050 deg. C in a multianvil press with a Walker-type module. The compound crystallizes in the space group Pnma (no. 62) with the lattice parameters a=829.7(2), b=759.6(2), and c=1726.8(4) pm (Z=16). The high-pressure compound HP-LiB{sub 3}O{sub 5} is built up from a three-dimensional network of BO{sub 4} tetrahedra and BO{sub 3} groups, which incorporates Li{sup +} ions in channels along the b-axis. Band assignments of measured IR- and Raman spectra were done via quantum-mechanical calculations. Additionally, the thermal behavior of HP-LiB{sub 3}O{sub 5} was investigated. - Graphical abstract: The new high-pressure compound HP-LiB{sub 3}O{sub 5} is built up from a three-dimensional network of BO4 tetrahedra and BO{sub 3} groups, which incorporates Li{sup +} ions in channels along the b-axis. In this paper, the synthesis, the crystal structure, and the properties of HP-LiB{sub 3}O{sub 5} are described. Highlights: > Synthesis of a new lithium borate with the composition HP-LiB{sub 3}O{sub 5} at high pressure. > In contrast to the non-centrosymmetric phase LiB{sub 3}O{sub 5}, this high-pressure phase is centrosymmetric. > First example of ternary alkali borates exhibiting threefold bridging oxygen atoms.

Neumair, Stephanie C.; Vanicek, Stefan [Institut fuer Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universitaet Innsbruck, Innrain 52a, A-6020 Innsbruck (Austria); Kaindl, Reinhard; Toebbens, Daniel M. [Institut fuer Mineralogie und Petrographie, Leopold-Franzens-Universitaet Innsbruck, Innrain 52, A-6020 Innsbruck (Austria); Wurst, Klaus [Institut fuer Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universitaet Innsbruck, Innrain 52a, A-6020 Innsbruck (Austria); Huppertz, Hubert, E-mail: Hubert.Huppertz@uibk.ac.at [Institut fuer Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universitaet Innsbruck, Innrain 52a, A-6020 Innsbruck (Austria)

2011-09-15T23:59:59.000Z

440

Rice-Ramsperger-Kassel-Marcus theoretical prediction of high-pressure Arrhenius parameters by nonlinear regression: application to silane and disilane decomposition  

Science Journals Connector (OSTI)

Rice-Ramsperger-Kassel-Marcus theoretical prediction of high-pressure Arrhenius parameters by nonlinear regression: application to silane and disilane decomposition ... The average SiNW growth rate using disilane (Si2H6) at 400 ... ... Thermal Decomposition Mechanism of Disilane ...

Karl F. Roenigk; Klavs F. Jensen; Robert W. Carr

1987-01-01T23:59:59.000Z

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


441

In situ determination of the spinel–post-spinel transition in Fe3O4 at high pressure and temperature by synchrotron X-ray diffraction  

Science Journals Connector (OSTI)

...Crystallography, 34, 210-213. Wang, Y., Rivers, M., Sutton...high-pressure facility for synchroton radiation research at GeoSoilEnviroCars...Technology, 7, 1490-1495. Wang, Y., Rivers, M., Sutton...Swiss-army-knife approach to synchroton-based experimental studies...

K. Schollenbruch; A.B. Woodland; D.J. Frost; Y. Wang; T. Sanehira; F. Langenhorst

442

GEOPHYSICAL RESEARCH LETTERS, VOL. 24, NO. 24, PAGES 3269-3272, DECEMBER 15, 1997 Ab initio elasticity of three high-pressure polymorphs  

E-Print Network [OSTI]

. Full elastic constant tensors of three high- pressure polymorphs of silica: stishovite, CaCl2-type stishovite to the CaCl2 structure at 47 GPa. At this phase transition, the isotropically averaged shear wave of two. The trans- formation of the CaCl2 phase to the columbite phase at 98 GPa is accompanied

Stixrude, Lars

443

Large volume high-pressure cell for inelastic neutron scattering W. Wang, D. A. Sokolov, A. D. Huxley, and K. V. Kamenev  

E-Print Network [OSTI]

Large volume high-pressure cell for inelastic neutron scattering W. Wang, D. A. Sokolov, A. D for inelastic neutron scattering measurements of quantum fluids and solids Rev. Sci. Instrum. 84, 015101 (2013) TOF-SEMSANS--Time-of-flight spin-echo modulated small-angle neutron scattering J. Appl. Phys. 112

Hall, Christopher

444

Application of wavelength-scanned wavelength-modulation spectroscopy H2O absorption measurements in an engineering-scale high-pressure coal gasifier  

Science Journals Connector (OSTI)

A real-time, in situ water vapor (H2O) sensor using a tunable diode laser near 1,352 nm was developed to continuously monitor water vapor in the synthesis gas of an engineering-scale high-pressure coal gasifier....

Kai Sun; Ritobrata Sur; Jay B. Jeffries; Ronald K. Hanson; Tommy Clark…

2014-10-01T23:59:59.000Z

445

Chapter 13 - Energy Conversion of Biomass and Recycling of Waste Plastics Using Supercritical Fluid, Subcritical Fluid and High-Pressure Superheated Steam  

Science Journals Connector (OSTI)

Abstract Utilization of unused or waste biomass as fuels is receiving much attention owing to the reduction of CO2 emission and the development of alternative energy to expensive fossil fuels. On the other hand, the recycling of waste plastics is important for the prevention of the exhaustion of fossil resources. In this chapter, typical several examples of the energy conversion of biomass and the recycling of waste plastics using supercritical fluid, subcritical fluid, and high-pressure superheated steam were introduced: (1) bioethanol production from paper sludge with subcritical water, (2) hydrogen production from various biomass with high-pressure superheated steam, (3) production of composite solid fuel from waste biomass and plastics with subcritical water, (4) waste treatment and recovery of thermal energy with high-pressure superheated steam oxidation, (5) recycling of carbon fiber-reinforced plastic with high-pressure superheated steam and supercritical alcohol, (6) recycling of laminate film with subcritical water, and (7) recycling of cross-linked polyethylene with supercritical methanol.

Idzumi Okajima; Takeshi Sako

2014-01-01T23:59:59.000Z

446

Structural change associated with the incommensurate-normal phase transition in akermanite, Ca2MgSi2O7, at high pressure  

Science Journals Connector (OSTI)

...?The structural changes associated with the incommensurate (IC)-normal (N) phase transition in akermanite have been studied with high-pressure single-...a and c axes are 0.00280(10) and 0.00418(6)?GPa?1 for th...

Hexiong Yang; Robert M. Hazen; Robert T. Downs…

1997-09-01T23:59:59.000Z

447

High spin polarization at room temperature in Ge-substituted Fe{sub 3}O{sub 4} epitaxial thin film grown under high oxygen pressure  

SciTech Connect (OSTI)

Epitaxial thin films of room-temperature ferrimagnetic (Fe,Ge){sub 3}O{sub 4} were fabricated using pulsed laser deposition. Films with a single-phase spinel structure were grown under high oxygen pressures (0.01–0.6?Pa). The carrier transport across (Fe,Ge){sub 3}O{sub 4}/Nb:SrTiO{sub 3} interface was studied to estimate the spin polarization of (Fe, Ge){sub 3}O{sub 4}. Current–voltage curves of Fe{sub 2.8}Ge{sub 0.2}O{sub 4}/Nb:SrTiO{sub 3} junction showed rectifying behavior even at 300?K whereas Fe{sub 3}O{sub 4}/Nb:SrTiO{sub 3} junction showed ohmic behavior. Calculations based on a model for a Schottky contact with a ferromagnetic component yielded a spin polarization of 0.50 at 300?K for Fe{sub 2.8}Ge{sub 0.2}O{sub 4}, indicating its potential as a promising spin injector.

Seki, Munetoshi, E-mail: m-seki@ee.t.u-tokyo.ac.jp; Takahashi, Masanao; Ohshima, Toshiyuki; Yamahara, Hiroyasu; Tabata, Hitoshi [Department of Electrical Engineering and Information Systems, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)] [Department of Electrical Engineering and Information Systems, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)

2013-11-18T23:59:59.000Z

448

Atmospheric-Pressure Cold Plasma for Preparation of High Performance Pt/TiO2 Photocatalyst and Its Mechanism  

Science Journals Connector (OSTI)

Atmospheric-pressure dielectric barrier discharge (DBD) cold plasma was employed to fabricate Pt/TiO2 photocatalyst using the mixture of Ar and H2 as working gas. X-ray photoelectron microscopy (XPS) and transmis...

Lanbo Di; Xiuling Zhang; Zhijian Xu; Kai Wang

2014-03-01T23:59:59.000Z

449

Reviving Abandoned Reservoirs with High-Pressure Air Injection: Application in a Fractured and Karsted Dolomite Reservoir  

SciTech Connect (OSTI)

Despite declining production rates, existing reservoirs in the United States contain vast volumes of remaining oil that is not being effectively recovered. This oil resource constitutes a huge target for the development and application of modern, cost-effective technologies for producing oil. Chief among the barriers to the recovery of this oil are the high costs of designing and implementing conventional advanced recovery technologies in these mature, in many cases pressure-depleted, reservoirs. An additional, increasingly significant barrier is the lack of vital technical expertise necessary for the application of these technologies. This lack of expertise is especially notable among the small operators and independents that operate many of these mature, yet oil-rich, reservoirs. We addressed these barriers to more effective oil recovery by developing, testing, applying, and documenting an innovative technology that can be used by even the smallest operator to significantly increase the flow of oil from mature U.S. reservoirs. The Bureau of Economic Geology and Goldrus Producing Company assembled a multidisciplinary team of geoscientists and engineers to evaluate the applicability of high-pressure air injection (HPAI) in revitalizing a nearly abandoned carbonate reservoir in the Permian Basin of West Texas. The Permian Basin, the largest oil-bearing basin in North America, contains more than 70 billion barrels of remaining oil in place and is an ideal venue to validate this technology. We have demonstrated the potential of HPAI for oil-recovery improvement in preliminary laboratory tests and a reservoir pilot project. To more completely test the technology, this project emphasized detailed characterization of reservoir properties, which were integrated to access the effectiveness and economics of HPAI. The characterization phase of the project utilized geoscientists and petroleum engineers from the Bureau of Economic Geology and the Department of Petroleum Engineering (both at The University of Texas at Austin) to define the controls on fluid flow in the reservoir as a basis for developing a reservoir model. The successful development of HPAI technology has tremendous potential for increasing the flow of oil from deep carbonate reservoirs in the Permian Basin, a target resource that can be conservatively estimated at more than 1.5 billion barrels. Successful implementation in the field chosen for demonstration, for example, could result in the recovery of more than 34 million barrels of oil that will not otherwise be produced. Geological and petrophysical analysis of available data at Barnhart field reveals the following important observations: (1) the Barnhart Ellenburger reservoir is similar to most other Ellenburger reservoirs in terms of depositional facies, diagenesis, and petrophysical attributes; (2) the reservoir is characterized by low to moderate matrix porosity much like most other Ellenburger reservoirs in the Permian Basin; (3) karst processes (cave formation, infill, and collapse) have substantially altered stratigraphic architecture and reservoir properties; (4) porosity and permeability increase with depth and may be associated with the degree of karst-related diagenesis; (5) tectonic fractures overprint the reservoir, improving overall connectivity; (6) oil-saturation profiles show that the oil-water contact (OWC) is as much as 125 ft lower than previous estimations; (7) production history and trends suggest that this reservoir is very similar to other solution-gas-drive reservoirs in the Permian Basin; and (8) reservoir simulation study showed that the Barnhart reservoir is a good candidate for HPAI and that application of horizontal-well technology can improve ultimate resource recovery from the reservoir.

Robert Loucks; Stephen C. Ruppel; Dembla Dhiraj; Julia Gale; Jon Holder; Jeff Kane; Jon Olson; John A. Jackson; Katherine G. Jackson

2006-09-30T23:59:59.000Z

450

Effect of Blending on High-Pressure Laminar Flame Speed Measurements, Markstein Lengths, and Flame Stability of Hydrocarbons  

E-Print Network [OSTI]

, 5, and 10 .................................................. 40 Figure 26 Pure CH3OCH3 results for initial pressures of 1, 5, and 10 atm ................................................ 41 Figure 27 Flame speed results for 80/20 CH4/C2H6... .............................................................................................. 44 Figure 30 Flame speed results for 80/20 CH4/CH3OCH3 at initial pressures of 1, 5, and 10 atm compared to modeled results .................................................................................. 45 Figure 31 Flame speed results...

Lowry, William Baugh

2012-02-14T23:59:59.000Z

451

Field test of two high-pressure direct-contact downhole steam generators. Volume II. Oxygen/diesel system  

SciTech Connect (OSTI)

A field test of an oxygen/diesel fuel, direct contact steam generator has been completed. The field test, which was a part of Project DEEP STEAM and was sponsored by the US Department of Energy, involved the thermal stimulation of a well pattern in the Tar Zone of the Wilmington Oil Field. The activity was carried out in cooperation with the City of Long Beach and the Long Beach Oil Development Company. The steam generator was operated at ground level, with the steam and combustion products delivered to the reservoir through 2022 feet of calcium-silicate insulated tubing. The objectives of the test included demonstrations of safety, operational ease, reliability and lifetime; investigations of reservoir response, environmental impact, and economics; and comparison of those points with a second generator that used air rather than oxygen. The test was extensively instrumented to provide the required data. Excluding interruptions not attributable to the oxygen/diesel system, steam was injected 78% of the time. System lifetime was limited by the combustor, which required some parts replacement every 2 to 3 weeks. For the conditions of this particular test, the use of trucked-in LOX resulted in liess expense than did the production of the equivalent amount of high pressure air using on site compressors. No statistically significant production change in the eight-acre oxygen system well pattern occurred during the test, nor were any adverse effects on the reservoir character detected. Gas analyses during the field test showed very low levels of SOX (less than or equal to 1 ppM) in the generator gaseous effluent. The SOX and NOX data did not permit any conclusion to be drawn regarding reservoir scrubbing. Appreciable levels of CO (less than or equal to 5%) were measured at the generator, and in this case produced-gas analyses showed evidence of significant gas scrubbing. 64 figures, 10 tables.

Moreno, J.B.

1983-07-01T23:59:59.000Z

452

Field test of two high-pressure, direct-contact downhole steam generators. Volume I. Air/diesel system  

SciTech Connect (OSTI)

As a part of the Project DEEP STEAM to develop technology to more efficiently utilize steam for the recovery of heavy oil from deep reservoirs, a field test of a downhole steam generator (DSG) was performed. The DSG burned No. 2 diesel fuel in air and was a direct-contact, high pressure device which mixed the steam with the combustion products and injected the resulting mixture directly into the oil reservoir. The objectives of the test program included demonstration of long-term operation of a DSG, development of operational methods, assessment of the effects of the steam/combustion gases on the reservoir and comparison of this air/diesel DSG with an adjacent oxygen/diesel direct contact generator. Downhole operation of the air/diesel DSG was started in June 1981 and was terminated in late February 1982. During this period two units were placed downhole with the first operating for about 20 days. It was removed, the support systems were slightly modified, and the second one was operated for 106 days. During this latter interval the generator operated for 70% of the time with surface air compressor problems the primary source of the down time. Thermal contact, as evidenced by a temperature increase in the production well casing gases, and an oil production increase were measured in one of the four wells in the air/diesel pattern. Reservoir scrubbing of carbon monoxide was observed, but no conclusive data on scrubbing of SO/sub x/ and NO/sub x/ were obtained. Corrosion of the DSG combustor walls and some other parts of the downhole package were noted. Metallurgical studies have been completed and recommendations made for other materials that are expected to better withstand the downhole combustion environment. 39 figures, 8 tables.

Marshall, B.W.

1983-05-01T23:59:59.000Z

453

METC/3M Cooperative Agreement CRADA 94-024 high temperature high pressure filter materials exposure test program. Volume 1, Final report  

SciTech Connect (OSTI)

In conjunction with shakedown, operation, and desulfurization testing at the Morgantown Energy Technology Center (METC) 10 in. Fluid Bed Gasification and Cleanup facility, a series of tests was completed in cooperation with the Minnesota Mining and Manufacturing Company (3M). This cooperative research and development agreement (CRADA) between METC and 3M was to evaluate exposure of 3M SICONEX{trademark} fiber-reinforced ceramic and NEXTEL{trademark} 312 and 550 ceramic fabric materials to a gasifying environment at high temperatures (1000--1100{degree}F) and high pressure (300 psia). Minnesota Mining and Manufacturing Company (3M) provided two 60 mm I.D. {times} 0.5 m SICONEX{trademark} spools and one each of the NEXTEL{trademark} 312 and 550 ceramic fabrics for exposure to coal gas from the METC gasifier. METC installed the materials in a vessel existing in the METC Cleanup Facility and provided process data in exchange for ceramic filter and ash/char characterization. Details of the CRADA are found in CRADA 94-024. This report contains METC`s contribution to CRADA 94-024. Four gasifier runs were conducted over a five month period to accumulate 483 hours of operation. During this time, 2 LayCer{trademark} 70/3 filters were used for filtering the coal gas while the SICONEX{trademark} and NEXTEL{trademark} were exposed along side of the filters. During one 89 hour test, one Laycer{trademark} 70/3 candle was installed with a 3M ceramic composite filter. The face velocity through the candles was maintained nominally at 2.5 ft/min throughout the testing.

NONE

1995-06-01T23:59:59.000Z

454

08FFL-0020Influence of High Fuel Rail Pressure and Urea Selective Catalytic Reduction on PM Formation in an Off-Highway Heavy-Duty Diesel Engine  

SciTech Connect (OSTI)

The influence of fuel rail pressure (FRP) and urea-selective catalytic reduction (SCR) on particulate matter (PM) formation is investigated in this paper along with notes regarding the NOx and other emissions. Increasing FRP was shown to reduce the overall soot and total PM mass for four operating conditions. These conditions included two high speed conditions (2400 rpm at 540 and 270 Nm of torque) and two moderated speed conditions (1400 rpm at 488 and 325 Nm). The concentrations of CO2 and NOx increased with fuel rail pressure and this is attributed to improved fuel-air mixing. Interestingly, the level of unburned hydrocarbons remained constant (or increased slightly) with increased FRP. PM concentration was measured using an AVL smoke meter and scanning mobility particle sizer (SMPS); and total PM was collected using standard gravimetric techniques. These results showed that the smoke number and particulate concentrations decrease with increasing FRP. However the decrease becomes more gradual as very high rail pressures. Additionally, the total PM decreased with increasing FRP; however, the soluble organic fraction (SOF) reaches a maximum after which it declines with higher rail pressure. The total PM was collected for the two 1400 rpm conditions downstream of the engine, diesel oxidation catalyst, and a urea-SCR catalyst. The results show that significant PM reduction occurs in the SCR catalyst even during high rates of urea dosage. Analysis of the PM indicates that residual SOF is burned up in the SCR catalyst.

Kass, Michael D [ORNL; Domingo, Norberto [ORNL; Storey, John Morse [ORNL; Lewis Sr, Samuel Arthur [ORNL

2008-01-01T23:59:59.000Z

455

Apparatus and methods of reheating gas turbine cooling steam and high pressure steam turbine exhaust in a combined cycle power generating system  

DOE Patents [OSTI]

In a combined cycle system having a multi-pressure heat recovery steam generator, a gas turbine and steam turbine, steam for cooling gas turbine components is supplied from the intermediate pressure section of the heat recovery steam generator supplemented by a portion of the steam exhausting from the HP section of the steam turbine, steam from the gas turbine cooling cycle and the exhaust from the HP section of the steam turbine are combined for flow through a reheat section of the HRSG. The reheated steam is supplied to the IP section inlet of the steam turbi