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1

Lightweight, all-metal hose assembly has high flexibility and strength over wide range of temperature and pressure  

NASA Technical Reports Server (NTRS)

Lightweight flexible, metal braid reinforced hose assembly is used in high and low pressure oxygen, helium, and hydrogen systems. These hose assemblies have been successfully used on the Saturn-2 stage to provide joints of sufficient flexibility to absorb movement resulting from temperature variations.

Bessing, L. L.

1966-01-01

2

Effects of using long breathing hoses upon mask pressure.  

PubMed

Effects of using oxygen breathing hoses from 0.9 to 8.2 m (3 to 27 ft) long and mask fit upon mask pressure during 0.75 to 12-s decompressions from 2,438 m (8,000 ft) to either 6,096, 10,668, or 15,240 m (20,000, 35,000 or 50,000 ft) were determined. Peak mask pressures and duration of high mask pressure were related to mask fit, mask and hose stretch compliance, pressure differential, decompression rate, and other factors, with mask pressure increasing with hose length. Peak mask pressures frequently exceeded 80 mm Hg, a high pressure associated with increased incidence of pulmonary damage. Cargo-type aircraft, however, have sufficiently large volumes so that they will not decompress rapidly enough to have high mask pressure, even with an 8.2-m long hose. Long breathing hoses should not be used in smaller aircraft since small cabin volume will result in rapid decompression rates and high mask pressure. Above a flight altitude of 2,438 m, oxygen should always be breathed if hoses longer than 2.9 m (9 ft) are used. This would help prevent hypoxia, associated with the need to deplete air in the hose before oxygen is breathed, should cabin pressure be lost at a high altitude. The fastest decompression rates compatible with preventing mask pressures from exceding 80 mm Hg during decompressions to different altitudes with different length breathing hoses are given. PMID:637791

Cooke, J P; Olson, R M; Maloney, T M

1978-02-01

3

46 CFR 154.554 - Cargo hose: Bursting pressure.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 false Cargo hose: Bursting pressure. 154.554 Section 154.554 Shipping...Hose § 154.554 Cargo hose: Bursting pressure. Cargo hose that may be exposed to the pressure in the cargo tank, the cargo pump...

2014-10-01

4

46 CFR 154.554 - Cargo hose: Bursting pressure.  

Code of Federal Regulations, 2010 CFR

... § 154.554 Cargo hose: Bursting pressure. Cargo hose that may be exposed to the pressure in the cargo tank, the cargo pump discharge, or the vapor compressor discharge must have a bursting pressure of at least five times the maximum...

2010-10-01

5

46 CFR 154.554 - Cargo hose: Bursting pressure.  

Code of Federal Regulations, 2012 CFR

... § 154.554 Cargo hose: Bursting pressure. Cargo hose that may be exposed to the pressure in the cargo tank, the cargo pump discharge, or the vapor compressor discharge must have a bursting pressure of at least five times the maximum...

2012-10-01

6

46 CFR 154.554 - Cargo hose: Bursting pressure.  

Code of Federal Regulations, 2013 CFR

... § 154.554 Cargo hose: Bursting pressure. Cargo hose that may be exposed to the pressure in the cargo tank, the cargo pump discharge, or the vapor compressor discharge must have a bursting pressure of at least five times the maximum...

2013-10-01

7

46 CFR 154.554 - Cargo hose: Bursting pressure.  

Code of Federal Regulations, 2011 CFR

... § 154.554 Cargo hose: Bursting pressure. Cargo hose that may be exposed to the pressure in the cargo tank, the cargo pump discharge, or the vapor compressor discharge must have a bursting pressure of at least five times the maximum...

2011-10-01

8

Hand-tightened, high-pressure seal  

NASA Technical Reports Server (NTRS)

To provide flared tubing and hose connections for high-pressure hand tightened cryogenic service, a 1/4-inch male AN seal was modified by machining to receive a special, double-truncated-cone-shaped Kel-F washer between it and the flared flex hose connector.

Meyer, W. A.

1968-01-01

9

Simulations of Ion-Hose Instability with Pressure Profiles For DARHT-II Long-Pulse Experiments  

Microsoft Academic Search

Ion-hose instability growth of the 2-mus electron beam pulses will be studied during the Phase-II commissioning of the DARHT-II Facility. We have done simulations in support of the experiment using pressure profiles estimated for different pumping arrangements along the accelerator. Results of these simulations are reported in this paper and compared to simulation results reported previously using constant pressure profile

K. C. Dominic Chan; Harold A. Davis; C. A. Ekdahl; T. P. Hughes; T. C. Genoni; Yan Tang; M. E. Schulze

2005-01-01

10

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

NASA Astrophysics Data System (ADS)

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

Kaluza, M. C.; Mangles, S. P. D.; Thomas, A. G. R.; Najmudin, Z.; Dangor, A. E.; Murphy, C. D.; Collier, J. L.; Divall, E. J.; Foster, P. S.; Hooker, C. J.; Langley, A. J.; Smith, J.; Krushelnick, K.

2010-08-01

11

Method for predicting frictional loss in metal bellows and flexible hose  

NASA Technical Reports Server (NTRS)

Test date obtained concerning the frictional pressure loss to fluids flowing in unsleeved bellows and flexible hose. This data should be useful in the design of fluid systems where high delivery velocities are involved and flexible hose or bellows must be employed.

Cleveland, J. R.; Daniels, C. M.

1966-01-01

12

Fatigue testing of corrugated and Teflon hoses  

NASA Technical Reports Server (NTRS)

Single and two-phase heat transport systems for the thermal control of large space facilities require fluid lines that traverse joints and either rotate or move in some other manner. Flexible hoses are being considered as one means of traversing these joints. To test the resilience of flexible hoses to bending stress, a test assembly was constructed to determine the number of flexing cycles the hoses could withstand before losing their ability to maintain a constant pressure. Corrugated metal hoses and Teflon hoses were tested at different pressures with nitrogen gas. The metal hoses had lives ranging from 30,000 to 100,000 flexing cycles. But, even after 400,000 cycles, the Teflon hoses remained essentially intact, though some leakage in the convoluted Teflon is noted.

Benner, Steve M.; Swanson, Theodore D.; Costello, Frederick A.

1990-01-01

13

49 CFR 178.337-9 - Pressure relief devices, piping, valves, hoses, and fittings.  

Code of Federal Regulations, 2010 CFR

...fittings. (a) Pressure relief devices. (1) See § 173.315...pump seals and pressure relief devices, must be at least 4 times...heavier, except for sacrificial devices. Malleable metal, stainless...used in the construction of primary valve body parts and...

2010-10-01

14

Fluid Flow through Pipes--Another Look at Fire Hoses and Garden Hoses.  

ERIC Educational Resources Information Center

The forward force of water on a hose is calculated using only the pressure gradient, the radius and length of the hose. The misconception about recoil on the nozzle is discussed. Dissipation energy and the consequent heat generation in a fluid flow are also described. (KR)

Brouwer, W.; Paranjape, B. V.

1991-01-01

15

Rotary Coupling Extends Life Of Hose  

NASA Technical Reports Server (NTRS)

Oscillating rotary coupling enables hose to withstand bending oscillations without leakage. Intended for use where hose connects to stationary structure at one end and to oscillating structure on other end. Coupling, (a sun-and-planetary pulley system), eliminates fatigue stress at fixed end. Pulley coupling requires less hose than conventional helical-wrap couplings, and its weight, pressure drop, heat loss or gain, and fluid contents also less. Conceived for use on Space Station to transfer vapors across rotary joints to directional radiators for condensation or to transfer liquids to gimballed payloads for evaporation. On Earth, used to carry working fluids to and from evaporative solar collectors following path of Sun.

Benner, Steve; Costello, Frederick; Swanson, Theodore

1991-01-01

16

Model to Design Drip Hose Lateral Line  

NASA Astrophysics Data System (ADS)

Introduction The design criterion for non-pressure compensating drip hose is normally to have 10% of flow variation (?q) in the lateral line, corresponding to 20% of head pressure variation (?H). Longer lateral lines in drip irrigation systems using conventional drippers provide cost reduction, but it is necessary to obtain to the uniformity of irrigation [1]. The use of ?q higher levels can provide longer lateral lines. [4] proposes the use of a 30% ?q and he found that this value resulted in distribution uniformity over 80%. [1] considered it is possible to extend the lateral line length using two emitters spacing in different section. He assumed that the spacing changing point would be at 40% of the total length, because this is approximately the location of the average flow according with [2]. [3] found that, for practical purposes, the average pressure is located at 40% of the length of the lateral line and that until this point it has already consumed 75% of total pressure head loss (hf ). In this case, the challenge for designers is getting longer lateral lines with high values of uniformity. Objective The objective of this study was to develop a model to design longer lateral lines using non-pressure compensating drip hose. Using the developed model, the hypotheses to be evaluated were: a) the use of two different spacing between emitters in the same lateral line allows longer length; b) it is possible to get longer lateral lines using high values of pressure variation in the lateral lines since the distribution uniformity stays below allowable limits. Methodology A computer program was developed in Delphi® based on the model developed and it is able to design lateral lines in level using non-pressure compensating drip hose. The input data are: desired distribution uniformity (DU); initial and final pressure in the lateral line; coefficients of relationship between emitter discharge and pressure head; hose internal diameter; pipe cross-sectional area with the dripper; and roughness coefficient for the Hazen-Williams equation. The program allows calculate the lateral line length with three possibilities: selecting two spacing between emitters and defining the exchange point; using two pre-established spacing between emitters and calculating the length of each section with different spacing; using one emitter spacing. Results Results showed that the use of two sections with different spacing between drippers in the lateral line didn't allow longer length but got better uniformity when compared with lateral line with one spacing between emitters. The adoption of two spacing increased the flow rate per meter in the final section which represented approximately 80% of the lateral line total length and this justifies their use. The software allowed DU above 90% with pressure head variation of 40% and the use of two spacing between emitters. Conclusions The developed model/software showed to be accurate, easy to handle and useful for lateral line design using non-pressure compensating drip hose. References [1] ANDRADE, L. A. D. Estudo de uniformidade de emissão de água utilizando diferentes espaçamentos entre gotejadores na linha lateral. 2009. 87 f. Tese (Doutorado em Agronomia/Irigação e Drenagem) - Faculdade de Ciências Agronômicas, Universidade Estadual Paulista 'Julio de Mesquita Filho', Botucatu, (2009). [2] KELLER, J.; BLIESNER, R. D. Sprinkle and trickle irrigation. Caldwell: Blackburn Press, (1990). 652 p. [3] TALENS, J. A. M. Riego localizado y fertirrigacion. Madrid: Mundi-Prensa, (2002). 533 p. [4] WU, I. P. An assessment of hydraulic design of micro-irrigation systems. Agricultural Water Management, Amsterdan, v. 32, n. 3

Ludwig, Rafael; Cury Saad, João Carlos

2014-05-01

17

[High Pressure Gas Tanks  

NASA Technical Reports Server (NTRS)

Four high-pressure gas tanks, the basis of this study, were especially made by a private contractor and tested before being delivered to NASA Kennedy Space Center. In order to insure 100% reliability of each individual tank the staff at KSC decided to again submit the four tanks under more rigorous tests. These tests were conducted during a period from April 10 through May 8 at KSC. This application further validates the predictive safety model for accident prevention and system failure in the testing of four high-pressure gas tanks at Kennedy Space Center, called Continuous Hazard Tracking and Failure Prediction Methodology (CHTFPM). It is apparent from the variety of barriers available for a hazard control that some barriers will be more successful than others in providing protection. In order to complete the Barrier Analysis of the system, a Task Analysis and a Biomechanical Study were performed to establish the relationship between the degree of biomechanical non-conformities and the anomalies found within the system on particular joints of the body. This relationship was possible to obtain by conducting a Regression Analysis to the previously generated data. From the information derived the body segment with the lowest percentage of non-conformities was the neck flexion with 46.7%. Intense analysis of the system was conducted including Preliminary Hazard Analysis (PHA), Failure Mode and Effect Analysis (FMEA), and Barrier Analysis. These analyses resulted in the identification of occurrences of conditions, which may be becoming hazardous in the given system. These conditions, known as dendritics, may become hazards and could result in an accident, system malfunction, or unacceptable risk conditions. A total of 56 possible dendritics were identified. Work sampling was performed to observe the occurrence each dendritic. The out of control points generated from a Weighted c control chart along with a Pareto analysis indicate that the dendritics "Personnel not Wearing Proper Protective and Hose/tubing located in high-traffic area" which account for 59.18% of total dendritic frequency need to be addressed to reduce the chance of a hazard from occurring. However, the occurrences of some dendritics are more important than others. As a result immediate, from a Weighted c perspective, corrective action should be taken to ameliorate the cause of the Class A dendritic "Personnel located under suspended or moving loads" rather than just the most commonly occurring dendritics. In any case the vast majority of data obtained indicates that testing operations possess a relatively high degree of safety.

Quintana, Rolando

2002-01-01

18

Ion-Hose Instability in a High Current, Long-Pulse Accelerator  

NASA Astrophysics Data System (ADS)

The ion-hose instability is a transverse electrostatic instability which occurs on electron beams in the presence of a low-density ion channel. In the DARHT-2 accelerator, the 2 kA, 2 ?sec beam pulse produces an ion channel through impact ionization of the residual background gas (1.5× 10-7 torr average). A calculation of the linear growth by R. J. Briggs indicated that the instability could be strong enough to affect the radiographic application of DARHT, which requires that transverse oscillations be small compared to the beam radius. We present semi-analytical theory and 3-D particle-in-cell simulations (using the LSP code) of the linear and non-linear growth of the instability, including the effects of the temporal change in the ion density, spatially decreasing beam radius etc. We find that the number of e-foldings for a particular beam slice is given approximately by the analytic expression for a uniform channel using an average value for the channel density. Hence, in the linear regime, the number of e-foldings increases linearly from head to tail of the beam pulse. We also find that growth is suppressed by non-linear effects at relatively small amplitudes of the electron beam. This is because the ion oscillation amplitude is several times larger than that of the beam, allowing non-linear effects to come into play.

Hughes, Thomas P.; Genoni, Thomas C.

2002-04-01

19

Hypertension (High Blood Pressure)  

MedlinePLUS

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20

High Blood Pressure (Hypertension)  

MedlinePLUS

... and Diabetes Heart Health for Women High Blood Pressure (Hypertension) Print and Share (PDF 109 KB) En ... Who is at risk? How is high blood pressure treated? Understanding your blood pressure: What do the ...

21

46 CFR 98.25-80 - Cargo hose.  

Code of Federal Regulations, 2010 CFR

...five times the maximum safety relief valve setting of the tank. (c) Hose...discharge pressure of pumps or vapor compressors shall be designed for a bursting...of the pump or compressor relief valve. (d) Before being placed...

2010-10-01

22

High Blood Pressure  

MedlinePLUS

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

23

High Blood Pressure (Hypertension)  

MedlinePLUS

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24

High blood pressure - infants  

MedlinePLUS

... these numbers can be too high. Several factors affect blood pressure, including: Hormones The health of the heart and blood vessels The health of the kidneys High blood pressure in infants may be due to kidney or heart disease ...

25

Measuring multi-directional structure-borne sound transfer through a fluid filled and pressurized bellows or flexible hose  

NASA Astrophysics Data System (ADS)

A test facility for characterizing multidirectional sound transfer properties is described. A flexible bellows is clamped between two blocks which vibrate as rigid bodies in the frequency range studied. The upper block is on the machine side of the mounting and serves as an excitation block. The lower block determines the force which would be exerted by the bellows on a high impedance pipe system, i.e., the blocked force. An annular block between two bellows the lower of which is connected to a heavy foundation, eliminates fluid borne sound transfer during tests. Transfer functions can be measured for separate excitation by each of six orthogonal translations and rotations.

Verheij, J. W.

1980-12-01

26

High temperature pressure gauge  

DOEpatents

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)

1981-01-01

27

Living with High Blood Pressure  

MedlinePLUS

... the NHLBI on Twitter. Living With High Blood Pressure If you have high blood pressure (HBP), you' ... Have High Blood Pressure Web page. High Blood Pressure and Pregnancy Many pregnant women who have HBP ...

28

High pressure counterflow CHF.  

E-print Network

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

1975-01-01

29

BIOMACROMOLECULES UNDER HIGH HYDROSTATIC PRESSURE  

E-print Network

BIOMACROMOLECULES UNDER HIGH HYDROSTATIC PRESSURE A Dissertation Presented to the Faculty HIGH HYDROSTATIC PRESSURE Nozomi Ando, Ph.D. Cornell University 2009 Protein pressure denaturation denaturation studies. Recent studies imply that the mechanism of pressure denaturation is the penetration

Gruner, Sol M.

30

High pressure nitriding  

SciTech Connect

The aim of the presented research project is the development of a new high pressure nitriding process, which avoids disadvantages of conventional nitriding processes and allows for new applications. Up to now, a nitriding furnace has been constructed and several investigations have been made in order to characterize the influence of pressure on the nitriding process. In this paper, connections between pressure in the range of 2 to 12 atm and the corresponding nitride layer formation for the steel grades AISI 1045, H11 and a nitriding steel are discussed. Results of the nitride layer formation are presented. For all steel grades, a growth of nitride layers with increasing pressure was obtained. Steels with passive layers, as the warm working steel H11, showed a better nitriding behavior at elevated pressure.

Jung, M.; Hoffmann, F.T.; Mayr, P. [Stiftung Inst. fuer Werkstofftechnik, Bremen (Germany); Minarski, P. [ALD Vacuum Technologies GmbH, Erlensee (Germany)

1995-12-31

31

High Blood Pressure  

NSDL National Science Digital Library

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

American Association for the Advancement of Science (;)

2004-01-01

32

Investigation of Radiation and Chemical Resistance of Flexible HLW Transfer Hose  

SciTech Connect

A chemical transfer hose constructed of an EPDM (ethylene-propylene diene monomer) outer covering with a modified cross-linked polyethylene (XLPE) lining was evaluated for use in high level radioactive waste transfer applications. Laboratory analysis involved characterization of the hose liner after irradiation to doses of 50 to 300 Mrad and subsequent exposure to 25% NaOH solution at 93 C for 30 days, simulating 6 months intermittent service. The XLPE liner mechanical and structural properties were characterized at varying dose levels. Burst testing of irradiated hose assemblies was also performed. Literature review and test results suggest that radiation effects below doses of 100 kGy are minimal, with acceptable property changes to 500 kGy. Higher doses may be feasible. At a bounding dose of 2.5 MGy, the burst pressure is reduced to the working pressure (1.38 MPa) at room temperature. Radiation exposure slightly reduces liner tensile strength, with more significant decrease in liner elongation. Subsequent exposure to caustic solutions at elevated temperature slightly increases elongation, suggesting an immersion/hydrolytic effect or possible thermal annealing of radiation damage. This paper summarizes the laboratory results and recommendations for field deployment.

E. Skidmore; Billings, K.; Hubbard, M.

2010-03-24

33

33 CFR 183.560 - Hose clamps: Installation.  

Code of Federal Regulations, 2010 CFR

...EQUIPMENT Fuel Systems Manufacturer Requirements § 183.560 Hose clamps: Installation. Each hose clamp on a hose from the fuel tank to the fuel inlet connection on the engine, a hose between the fuel pump and the carburetor, or a...

2010-07-01

34

High pressure oxygen furnace  

DOEpatents

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)

1992-01-01

35

High pressure furnace  

DOEpatents

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

Morris, Donald E. (Kensington, CA)

1993-01-01

36

High pressure gas target  

NASA Astrophysics Data System (ADS)

Compact, high pressure, high current gas target features all metal construction and semi-automatic window assembly change. The unique aspect of this target is the domed-shaped window. The Havar alloy window is electron beam welded to a metal ring, thus forming one, interchangeable assembly. The window assembly is sealed by knife-edges locked by a pneumatic toggle allowing a quick, in situ window change.

Gelbart, W.; Johnson, R. R.; Abeysekera, B.

2012-12-01

37

High Blood Pressure Fact Sheet  

MedlinePLUS

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38

What Is High Blood Pressure?  

MedlinePLUS

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39

High Blood Pressure and Women  

MedlinePLUS

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40

High pressure induced superconductivity  

Microsoft Academic Search

We have developed complex extreme condition of very low temperature down to 30 mK and ultra high pressure exceeding 200 GPa by assembling compact diamond anvil cell (DAC) on a powerful 3He\\/4He dilution refrigerator. We have also developed measuring techniques of electrical resistance, magnetization and optical measurement for the sample confined in the sample space of the DAC. Using the

K. Amaya; K. Shimizu

2003-01-01

41

What Causes High Blood Pressure?  

MedlinePLUS

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42

Controlling your high blood pressure  

MedlinePLUS

Hypertension is another term used to describe high blood pressure. High blood pressure can lead to stroke, heart attack, heart failure, kidney disease, and early death. You are more likely to have high ...

43

Questions and Answers about High Blood Pressure  

MedlinePLUS

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44

Chromium at High Pressure  

NASA Astrophysics Data System (ADS)

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

Jaramillo, Rafael

2012-02-01

45

Pregnancy and High Blood Pressure  

MedlinePLUS Videos and Cool Tools

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46

Stroke and High Blood Pressure  

MedlinePLUS

Stroke and High Blood Pressure Updated:Jan 6,2015 Stroke is a leading cause of death and severe, long-term disability. Since managing high blood pressure, also called HBP or hypertension, is the most ...

47

Melting at High Pressures  

NASA Astrophysics Data System (ADS)

At high pressures, melts tend to become more similar to the crystalline solid phases. In general, the change in volume with melting, ? V, becomes small and the entropy of melting, ? S, becomes constant leading to a melting curve that bends over and approaches a constant. [1] Solids near melting also show approaching dynamical instabilities near melting, such as enhanced diffusivities in a premelting region. [2] Some materials display different behavior. Na, for example, shows a melting curve with a maximum followed by a negative pressure slope down to low temperatures. [3] Raty et al. proposed that the electronic structure of liquid and solid sodium are different, due to opening of a pseudogap in liquid Na, leading to increased density of the liquid and a negative melting slope. [4] We have performed first-principles molecular dynamics simulations for solid and liquid sodium as a function of P and T, and find no evidence of a pseudogap or electronic transition in Na. Rather we find that liquid Na is denser due to closer first neighbors with icosohedral packing due to softening of the potential such as occurs in a Gaussian core potential. We are also performing first-principles MD for Mg2SiO4 liquid to understand diffusivity and dynamical properties of the melt using the QBOX code. Initial results show D=(14, 3.2, 16) 10-6 m2/s for (Mg,Si,O) at P=0 and 6000K and D=(5.7, 1.9, 9.2) 10-6 m2/s at 5000K. Lower temperature and higher pressure simulations are in progress. [1] R. E. Cohen, and Z. Gong, Phys. Rev. B 50, 12301 (1994). [2] R. E. Cohen, and J. Weitz, in Properties of Earth and Planetary Materials at High Pressure and Temperature, edited by M. H. Manghnani, and T. Yagi (AGU, Washington, D.C., 1998), pp. 185. [3] E. Gregoryanz et al., Phys. Rev. Lett. 94, 185502 (2005). [4] J.-Y. Raty, E. Schwegler, and S. A. Bonev, Nature 449, 448 (2007). [5] F. H. Stillinger, and P. G. Debenedetti, Biophysical Chemistry 105, 211 (2003).

Cohen, R. E.; Vorberger, J.; Militzer, B.; Caracas, R.; Gygi, F.

2008-12-01

48

High Blood Pressure in Pregnancy  

MedlinePLUS

What Is High Blood Pressure? Blood pressure is the amount of force exerted by the blood against the walls of the arteries. A person's blood ... disease. What Are the Effects of High Blood Pressure in Pregnancy? Although many pregnant women with high ...

49

Alloys For Flexible Hoses In A Corrosive Environment  

NASA Technical Reports Server (NTRS)

High-nickel alloy resists pitting corrosion. Report evaluates metal alloys for flexible hoses in corrosive environment. Tested to find alternatives to 304L stainless steel. Nineteen alloys selected for testing on basis of reputation for resistance to corrosion. Top five, in order of decreasing resistance to corrosion: Hastelloy(R) C-22, Inconel(R) 625, Hastelloy(R) C-276, Hastelloy(R) C-4, and Inco(R) alloy G-3. Of these, Hastelloy(R) C-22 found best for flexible-hose application.

Macdowell, Louis G., III; Ontiveros, Cordelia

1992-01-01

50

High Blood Pressure  

MedlinePLUS

Blood pressure is the force of your blood pushing against the walls of your arteries. Each time your heart ... it pumps blood into the arteries. Your blood pressure is highest when your heart beats, pumping the ...

51

High pressure mechanical seal  

NASA Technical Reports Server (NTRS)

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

Babel, Henry W. (Inventor); Fuson, Phillip L. (Inventor); Chickles, Colin D. (Inventor); Jones, Cherie A. (Inventor); Anderson, Raymond H. (Inventor)

1995-01-01

52

High pressure mechanical seal  

NASA Technical Reports Server (NTRS)

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

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

1996-01-01

53

MEASUREMENT OF ACOUSTIC IMPEDANCE OF THE POROUS WOVEN HOSES IN ENGINE INTAKE SYSTEMS IN THE PRESENCE OF MEAN FLOW  

Microsoft Academic Search

For the prediction of acoustic performance of an engine intake system with porous woven hose, the wall impedance of the hose must be known in the presence of mean flow. Here, the acoustic impedance is inversely estimated from an overdetermine d set of measured pressure transmission coefficients for specimens of different lengths and the reflection coefficient of end termination. The

Chul-Min Park; Yoshio Nakayama

54

33 CFR 183.558 - Hoses and connections.  

Code of Federal Regulations, 2010 CFR

...hose. (b) Each hose used— (1) For a...minutes when: (A) The hose is severed at the point...tank to the fuel inlet connection on the engine must be...minutes when: (A) The hose is severed at the point...insert; or (3) A hose clamp. (d) The...

2010-07-01

55

High pressure, high temperature transducer  

NASA Technical Reports Server (NTRS)

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

Vrolyk, John J. (Inventor)

1977-01-01

56

Failure analysis of braided U-shaped metal bellows flexible hoses  

NASA Astrophysics Data System (ADS)

Most of the research performed extensively reviews the effects of non-reinforced metal bellows and their pressurized characteristics. However, the majority of flex hoses are manufactured with reinforcement by the means of interweaved wire braids. For this research, the outer braid reinforced metal bellows flex hoses will be examined for their failure at differing lengths. The relationship with the bellows expansion joints is such that as the length of the flex hoses increases, the pressure at which squirm occurs decreases. As such, for the testing being performed, the same approach to failure is expected. As the length of the flex hose increases, it is predicted that the hose will fail at a decreasing pressure. Since the braid is the only thing that prevents the squirm from occurring, more of the load will be displaced from the bellows and into the braid. This will ultimately cause failure of the braid to occur at a lower pressure as the length of the hoses increase due to more of the load being transmitted from the bellows and into the braid.

Pierce, Stephen O.

57

High-pressure neutron diffraction  

SciTech Connect

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

Xu, Hongwu [Los Alamos National Laboratory

2011-01-10

58

High Blood Pressure in Pregnancy  

MedlinePLUS

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

59

Effects of long-hose breathing.  

PubMed

The need for aircrew members to use long breathing hoses between regulator and mask arises in the design of new transport aircraft and in several cargo operations requiring an open rear door. In this study, induced work of breathing through long hoses, the resulting changes in oxygen consumption, and comfort were studied in relation to altitude, hose length, and exercise level. Conclusions were that, above 18,000 ft (5.5 km), a 30-ft (9.1-m) hose is acceptable for all reasonable work levels; for altitudes between 13,000 and 18,000 ft (4.0 and 5.5 km), the hose length should preferably be 18 ft (5.5m), and at altitudes below 13,000 ft (4.0 km), hose length should be limited to 12 ft (3.6). Moreover, at ground level, the hose length should be limited to 6 ft (1.8 m) for all but sedentary activity. Should the potential for rapid decompression exist, at any altitude, volume considerations limit hose length to 18 ft (5.5 m) since larger hoses possess excessive regulator-to-mask dead space. PMID:637792

Olson, R M; Cooke, J P

1978-02-01

60

46 CFR 105.35-15 - Fire hose.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 2014-10-01 false Fire hose. 105.35-15 Section 105.35-15...FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Fire Extinguishing Equipment § 105.35-15 Fire hose. (a) One length of fire hose...

2014-10-01

61

46 CFR 105.35-15 - Fire hose.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Fire hose. 105.35-15 Section 105.35-15...FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Fire Extinguishing Equipment § 105.35-15 Fire hose. (a) One length of fire hose...

2013-10-01

62

46 CFR 105.35-15 - Fire hose.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 2010-10-01 false Fire hose. 105.35-15 Section 105.35-15...FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Fire Extinguishing Equipment § 105.35-15 Fire hose. (a) One length of fire hose...

2010-10-01

63

46 CFR 105.35-15 - Fire hose.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 2011-10-01 false Fire hose. 105.35-15 Section 105.35-15...FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Fire Extinguishing Equipment § 105.35-15 Fire hose. (a) One length of fire hose...

2011-10-01

64

46 CFR 105.35-15 - Fire hose.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 2012-10-01 false Fire hose. 105.35-15 Section 105.35-15...FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Fire Extinguishing Equipment § 105.35-15 Fire hose. (a) One length of fire hose...

2012-10-01

65

46 CFR 154.1170 - Hand hose line: General.  

Code of Federal Regulations, 2011 CFR

... 2011-10-01 2011-10-01 false Hand hose line: General. 154.1170 Section...Firefighting System: Dry Chemical § 154.1170 Hand hose line: General. Each dry chemical hand hose line must: (a) Not be longer...

2011-10-01

66

46 CFR 154.1170 - Hand hose line: General.  

Code of Federal Regulations, 2010 CFR

... 2010-10-01 2010-10-01 false Hand hose line: General. 154.1170 Section...Firefighting System: Dry Chemical § 154.1170 Hand hose line: General. Each dry chemical hand hose line must: (a) Not be longer...

2010-10-01

67

46 CFR 154.1170 - Hand hose line: General.  

Code of Federal Regulations, 2014 CFR

... 2014-10-01 2014-10-01 false Hand hose line: General. 154.1170 Section...Firefighting System: Dry Chemical § 154.1170 Hand hose line: General. Each dry chemical hand hose line must: (a) Not be longer...

2014-10-01

68

46 CFR 154.1170 - Hand hose line: General.  

Code of Federal Regulations, 2012 CFR

... 2012-10-01 2012-10-01 false Hand hose line: General. 154.1170 Section...Firefighting System: Dry Chemical § 154.1170 Hand hose line: General. Each dry chemical hand hose line must: (a) Not be longer...

2012-10-01

69

46 CFR 154.1170 - Hand hose line: General.  

Code of Federal Regulations, 2013 CFR

... 2013-10-01 2013-10-01 false Hand hose line: General. 154.1170 Section...Firefighting System: Dry Chemical § 154.1170 Hand hose line: General. Each dry chemical hand hose line must: (a) Not be longer...

2013-10-01

70

Electrokinetically pumped high pressure sprays  

DOEpatents

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)

2002-01-01

71

Electrokinetically pumped high pressure sprays  

DOEpatents

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)

2005-11-01

72

Fundamentals of high pressure adsorption  

SciTech Connect

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

2009-12-15

73

High pressure storage vessel  

DOEpatents

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

2013-08-27

74

High pressure synthesis gas fermentation  

SciTech Connect

Construction of the high pressure gas phase fermentation system is nearing completion. All non-explosion proof components will be housed separately in a gas-monitored plexiglas cabinet. A gas-monitoring system has been designed to ensure the safety of the operations in case of small or large accidental gas releases. Preliminary experiments investigating the effects of high pressure on Clostridium 1jungdahlii have shown that growth and CO uptake are not negatively affected and CO uptake by an increased total pressure of 100 psig at a syngas partial pressure of 10 psig.

Not Available

1991-01-01

75

Prediction of flow-induced failures of braided flexible hoses and bellows  

NASA Technical Reports Server (NTRS)

Analytical techniques were developed to evaluate braided hoses and bellows for possibility of flow induced resonance. These techniques determine likelihood of high cycle fatigue failure when such resonance exists.

Sack, L. E.; Nelson, R. L.; Mason, D. R.; Cooper, R. A.

1972-01-01

76

Internal Thermal Control System Hose Heat Transfer Fluid Thermal Expansion Evaluation Test Report  

NASA Technical Reports Server (NTRS)

During assembly of the International Space Station, the Internal Thermal Control Systems in adjacent modules are connected by jumper hoses referred to as integrated hose assemblies (IHAs). A test of an IHA has been performed at the Marshall Space Flight Center to determine whether the pressure in an IHA filled with heat transfer fluid would exceed the maximum design pressure when subjected to elevated temperatures (up to 60 C (140 F)) that may be experienced during storage or transportation. The results of the test show that the pressure in the IHA remains below 227 kPa (33 psia) (well below the 689 kPa (100 psia) maximum design pressure) even at a temperature of 71 C (160 F), with no indication of leakage or damage to the hose. Therefore, based on the results of this test, the IHA can safely be filled with coolant prior to launch. The test and results are documented in this Technical Memorandum.

Wieland, P. O.; Hawk, H. D.

2001-01-01

77

High pressure ices  

PubMed Central

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

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

2012-01-01

78

High amplitude sinusoidal pressure generator  

NASA Technical Reports Server (NTRS)

Generator is an inlet-area-modulated, gas-flow-through device utilizing hydrogen gas and a rotating disk for operation. Design enables generator to produce pressure oscillations as high as 120, 18, and 12 percent of the mean chamber pressure at frequencies of 1, 10, and 15 kHz, respectively.

Robinson, R. E.

1970-01-01

79

High Pressure Industrial Water Facility  

NASA Technical Reports Server (NTRS)

In conjunction with Space Shuttle Main Engine testing at Stennis, the Nordberg Water Pumps at the High Pressure Industrial Water Facility provide water for cooling the flame deflectors at the test stands during test firings.

1992-01-01

80

Pressure multiplier pumps offer high pressure capability  

Microsoft Academic Search

Need for pressure multiplier-type pumps was established in the 1960's. While stimulation treatments requiring pumping pressures in excess of 7500 psi were increasing, deep well drilling using the abrasive jet technique also was beginning to dictate the need for replacement or a change in the conventional reciprocating service pump. Today's pressure multiplier pump is superior to the reciprocating pump when

D. C. Cameron; F. M. Jr. Winn

1979-01-01

81

Electrokinetic high pressure hydraulic system  

DOEpatents

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

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

2000-01-01

82

High pressure ceramic joint  

DOEpatents

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.

1993-11-30

83

High pressure ceramic joint  

DOEpatents

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)

1993-01-01

84

30 CFR 18.39 - Hose conduit.  

Code of Federal Regulations, 2013 CFR

...Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.39 Hose...

2013-07-01

85

30 CFR 18.39 - Hose conduit.  

Code of Federal Regulations, 2010 CFR

...Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.39 Hose...

2010-07-01

86

30 CFR 18.39 - Hose conduit.  

Code of Federal Regulations, 2014 CFR

...Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES Construction and Design Requirements § 18.39 Hose...

2014-07-01

87

Beam hosing instability in overdense plasma  

SciTech Connect

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

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

2012-12-21

88

How Is High Blood Pressure Diagnosed?  

MedlinePLUS Videos and Cool Tools

... are here Home » Health Information for the Public » Health Topics » High Blood Pressure » How Is High Blood Pressure Diagnosed? Explore High Blood Pressure What Is... Other Names Causes Who Is at Risk Signs & Symptoms Diagnosis Treatments Prevention Living With Clinical ...

89

Avoid the Consequences of High Blood Pressure  

MedlinePLUS

... Stroke More Avoid the Consequences of High Blood Pressure Infographic Updated:Jun 19,2014 View a downloadable version of this infographic High Blood Pressure • Home • About High Blood Pressure (HBP) • Why HBP ...

90

High pressure liquid level monitor  

DOEpatents

A liquid level monitor for tracking the level of a coal slurry in a high-pressure vessel including a toroidal-shaped float with magnetically permeable bands thereon disposed within the vessel, two pairs of magnetic field generators and detectors disposed outside the vessel adjacent the top and bottom thereof and magnetically coupled to the magnetically permeable bands on the float, and signal processing circuitry for combining signals from the top and bottom detectors for generating a monotonically increasing analog control signal which is a function of liquid level. The control signal may be utilized to operate high-pressure control valves associated with processes in which the high-pressure vessel is used.

Bean, Vern E. (Frederick, MD); Long, Frederick G. (Ijamsville, MD)

1984-01-01

91

How Can High Blood Pressure Be Prevented?  

MedlinePLUS

... the NHLBI on Twitter. How Can High Blood Pressure Be Prevented? If You Have Normal Blood Pressure If you don't have high blood pressure ( ... Blood Pressure Treated?" If You Have High Blood Pressure If you have HBP, you can still take ...

92

High-pressure water facility  

NASA Technical Reports Server (NTRS)

NASA Test Operations Group employees, from left, Todd Pearson, Tim Delcuze and Rodney Wilkinson maintain a water pump in Stennis Space Center's high-pressure water facility. The three were part of a group of employees who rode out Hurricane Katrina at the facility and helped protect NASA's rocket engine test complex.

2006-01-01

93

High-speed pressure clamp.  

PubMed

We built a high-speed, pneumatic pressure clamp to stimulate patch-clamped membranes mechanically. The key control element is a newly designed differential valve that uses a single, nickel-plated piezoelectric bending element to control both pressure and vacuum. To minimize response time, the valve body was designed with minimum dead volume. The result is improved response time and stability with a threefold decrease in actuation latency. Tight valve clearances minimize the steady-state air flow, permitting us to use small resonant-piston pumps to supply pressure and vacuum. To protect the valve from water contamination in the event of a broken pipette, an optical sensor detects water entering the valve and increases pressure rapidly to clear the system. The open-loop time constant for pressure is 2.5 ms for a 100-mmHg step, and the closed-loop settling time is 500-600 micros. Valve actuation latency is 120 micros. The system performance is illustrated for mechanically induced changes in patch capacitance. PMID:12397401

Besch, Stephen R; Suchyna, Thomas; Sachs, Frederick

2002-10-01

94

46 CFR 98.25-80 - Cargo hose.  

Code of Federal Regulations, 2011 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-80 Cargo hose. (a) Cargo hose fabricated of seamless steel pipe with swivel joints,...

2011-10-01

95

46 CFR 98.25-80 - Cargo hose.  

Code of Federal Regulations, 2013 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-80 Cargo hose. (a) Cargo hose fabricated of seamless steel pipe with swivel joints,...

2013-10-01

96

46 CFR 98.25-80 - Cargo hose.  

Code of Federal Regulations, 2012 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-80 Cargo hose. (a) Cargo hose fabricated of seamless steel pipe with swivel joints,...

2012-10-01

97

46 CFR 98.25-80 - Cargo hose.  

Code of Federal Regulations, 2014 CFR

...MISCELLANEOUS VESSELS SPECIAL CONSTRUCTION, ARRANGEMENT, AND OTHER PROVISIONS FOR CERTAIN DANGEROUS CARGOES IN BULK Anhydrous Ammonia in Bulk § 98.25-80 Cargo hose. (a) Cargo hose fabricated of seamless steel pipe with swivel joints,...

2014-10-01

98

Crystalline diborane at high pressures  

NASA Astrophysics Data System (ADS)

High-pressure ground-state phases of crystalline diborane (B2H6) and their stability against decomposition into B and H are investigated by calculations within density-functional theory. Although B2H6 is thermodynamically unstable to phase separation into B and H in the intermediate pressure range, it is restabilized beyond 350 GPa. The candidate structures are then Pbcn and Cmcm, though at the level of the harmonic approximation the latter has some imaginary-frequency phonons. Both structures are metallic with quite high density of states at the Fermi energy. An estimate of superconducting transition temperature Tc is carried out for the Pbcn structure by using the extended McMillan formula, and the resulting Tc reaches around 100 K.

Abe, Kazutaka; Ashcroft, N. W.

2011-09-01

99

46 CFR 154.1155 - Hand hose line: Coverage.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Hand hose line: Coverage. 154.1155 Section...Firefighting System: Dry Chemical § 154.1155 Hand hose line: Coverage. The coverage for the area for a hand hose line under § 154.1150 must not...

2010-10-01

100

46 CFR 154.1155 - Hand hose line: Coverage.  

Code of Federal Regulations, 2014 CFR

...2014-10-01 2014-10-01 false Hand hose line: Coverage. 154.1155 Section...Firefighting System: Dry Chemical § 154.1155 Hand hose line: Coverage. The coverage for the area for a hand hose line under § 154.1150 must not...

2014-10-01

101

46 CFR 154.1155 - Hand hose line: Coverage.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Hand hose line: Coverage. 154.1155 Section...Firefighting System: Dry Chemical § 154.1155 Hand hose line: Coverage. The coverage for the area for a hand hose line under § 154.1150 must not...

2011-10-01

102

46 CFR 154.1155 - Hand hose line: Coverage.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Hand hose line: Coverage. 154.1155 Section...Firefighting System: Dry Chemical § 154.1155 Hand hose line: Coverage. The coverage for the area for a hand hose line under § 154.1150 must not...

2013-10-01

103

46 CFR 154.1155 - Hand hose line: Coverage.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Hand hose line: Coverage. 154.1155 Section...Firefighting System: Dry Chemical § 154.1155 Hand hose line: Coverage. The coverage for the area for a hand hose line under § 154.1150 must not...

2012-10-01

104

29 CFR 1910.158 - Standpipe and hose systems.  

Code of Federal Regulations, 2012 CFR

...cm) or smaller hose outlet used to meet this standard is equipped with hose connected and ready for use. In extremely cold climates where such installation may result in damaged equipment, the hose may be stored in another location provided it is...

2012-07-01

105

High-Pressure Protein Crystallography and NMR  

E-print Network

High-Pressure Protein Crystallography and NMR to Explore Protein Conformations Marcus D. Collins,1, energy landscape, protein thermodynamics, pressure cryocooling Abstract High-pressure methods for solving's native conformation, but also the higher free energy conformations. The ability of high-pressure meth

Gruner, Sol M.

106

High pressure xenon ionization detector  

DOEpatents

A method is provided for detecting ionization comprising allowing particles that cause ionization to contact high pressure xenon maintained at or near its critical point and measuring the amount of ionization. An apparatus is provided for detecting ionization, the apparatus comprising a vessel containing a ionizable medium, the vessel having an inlet to allow high pressure ionizable medium to enter the vessel, a means to permit particles that cause ionization of the medium to enter the vessel, an anode, a cathode, a grid and a plurality of annular field shaping rings, the field shaping rings being electrically isolated from one another, the anode, cathode, grid and field shaping rings being electrically isolated from one another in order to form an electric field between the cathode and the anode, the electric field originating at the anode and terminating at the cathode, the grid being disposed between the cathode and the anode, the field shaping rings being disposed between the cathode and the grid, the improvement comprising the medium being xenon and the vessel being maintained at a pressure of 50 to 70 atmospheres and a temperature of 0.degree. to 30.degree. C.

Markey, John K. (New Haven, CT)

1989-01-01

107

High pressure xenon ionization detector  

DOEpatents

A method is provided for detecting ionization comprising allowing particles that cause ionization to contact high pressure xenon maintained at or near its critical point and measuring the amount of ionization. An apparatus is provided for detecting ionization, the apparatus comprising a vessel containing a ionizable medium, the vessel having an inlet to allow high pressure ionizable medium to enter the vessel, a means to permit particles that cause ionization of the medium to enter the vessel, an anode, a cathode, a grid and a plurality of annular field shaping rings, the field shaping rings being electrically isolated from one another, the anode, cathode, grid and field shaping rings being electrically isolated from one another in order to form an electric field between the cathode and the anode, the electric field originating at the anode and terminating at the cathode, the grid being disposed between the cathode and the anode, the field shaping rings being disposed between the cathode and the grid, the improvement comprising the medium being xenon and the vessel being maintained at a pressure of 50 to 70 atmospheres and a temperature of 0 to 30 C. 2 figs.

Markey, J.K.

1989-11-14

108

Improved high pressure turbine shroud  

NASA Technical Reports Server (NTRS)

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

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

1977-01-01

109

Electokinetic high pressure hydraulic system  

DOEpatents

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

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

2000-01-01

110

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

SciTech Connect

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

TORRES, T.D.

2000-08-24

111

Electrical Transport Experiments at High Pressure  

SciTech Connect

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

2009-02-11

112

High Blood Pressure: Medicines to Help You  

MedlinePLUS

... of Women's Health High Blood Pressure--Medicines to Help You Click here for the Color Version (PDF ... saving medicines people can take every day to help control their high blood pressure. People who eat ...

113

More Americans Controlling Their High Blood Pressure  

MedlinePLUS

... enable JavaScript. More Americans Controlling Their High Blood Pressure Government researchers report the numbers are looking better, ... 2014 Related MedlinePlus Pages Health Statistics High Blood Pressure SUNDAY, Nov. 16, 2014 (HealthDay News) -- A growing ...

114

Feedthrough Seal For High-Pressure Vessel  

NASA Technical Reports Server (NTRS)

Combination of ceramic and plastic withstands many depressurizations. Stack of washers surrounds leadthrough electrode. Under pressure washers expand to fill leadthrough hole in high-pressure vessel. Seal thus formed withstands 20 or more pressurization/depressurization cycles. Seal composed of neoprene, polytetrafluoroethylene, nylon and high-purity, high-density commercial alumina ceramic.

Williams, R.; Mullins, O.; Smith, D.; Teasley, G.

1984-01-01

115

National High Blood Pressure Education Program Prevention,  

E-print Network

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

Bandettini, Peter A.

116

Cheese Manufacture Assisted by High Pressure  

Microsoft Academic Search

The processing of foods by high pressure is gaining commercial acceptance. Various food products processed by high pressure are now available in stores and the list of commercialized products is expected to expand as new applications are developed. Currently, industrial applications within the dairy industry are being sought. This article describes what high pressure processing is, presents some of the

M. F. San Martín-González; J. Welti-Chanes; G. V. Barbosa-Cánovas

2006-01-01

117

High-pressure microhydraulic actuator  

DOEpatents

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

2008-06-10

118

Medications for High Blood Pressure  

MedlinePLUS

... all parts of the body in vessels called arteries. Blood pressure is the force of the blood pushing ... the body and against the walls of the arteries. The higher the blood pressure, the greater the risk of stroke, heart ...

119

Evaluation of high temperature pressure sensors  

SciTech Connect

It is becoming more important to measure the pressure in high temperature environments in many industrial fields. However, there is no appropriate evaluation system and compensation method for high temperature pressure sensors since most pressure standards have been established at room temperature. In order to evaluate the high temperature pressure sensors used in harsh environments, such as high temperatures above 250 deg. C, a specialized system has been constructed and evaluated in this study. The pressure standard established at room temperature is connected to a high temperature pressure sensor through a chiller. The sensor can be evaluated in conditions of changing standard pressures at constant temperatures and of changing temperatures at constant pressures. According to the evaluation conditions, two compensation methods are proposed to eliminate deviation due to sensitivity changes and nonlinear behaviors except thermal hysteresis.

Choi, In-Mook; Woo, Sam-Yong; Kim, Yong-Kyu [Center for Mass-Related Quantities, Korea Research Institute of Standards and Science (KRISS), P.O. Box 102, Yuseong, Daejeon 305-600 (Korea, Republic of)

2011-03-15

120

High-Pressure Research in Organic Conductors  

NASA Astrophysics Data System (ADS)

High-pressure studies on organic conductors and superconductors are reviewed. It is stressed that almost all the organic conductors are studied by means of high pressures, but the role or meaning of pressure effect has been dependent on the salts and physics of interests. In organic molecular crystals, many intriguing physical phenomena such as the appearance of charge- and spin-density-waves, superconductivity, Mott insulator and charge ordering have been found. The application of hydrostatic and uniaxial pressures plays an essential role for understanding the nature of these electronic states, for guiding the material design, and for creating the unexpected quantum states as well as high-Tc superconductivities. This review includes the history, pressure techniques, and works under conventional pressures of up to 1.5 GPa, ultra-high pressures up to 10 GPa as well as uniaxial pressure, but the topics which are dealt with in this same special issue are not covered.

Murata, Keizo; Kagoshima, Seiichi; Yasuzuka, Syuma; Yoshino, Harukazu; Kondo, Ryusuke

2006-05-01

121

Notes 11. High pressure floating ring seals  

E-print Network

Notes 11. HIGH PRESSURE LONG OIL SEALS ? Dr. Luis San Andr?s 2009 1 Notes 11. High Pressure Long Oil Seals Small clearance oil seals minimize process gas leakage while allowing a limited lubricant flow accompanied by a pressure drop. Annular... PRESSURE LONG OIL SEALS ? Dr. Luis San Andr?s 2009 2 In practice, long seals integrate two sealing sides, each with a small clearance, and fed with some mineral lubricant at a pressure (Ps) slightly higher than the pressure (Pi) of the process product...

San Andres, Luis

2009-01-01

122

High-Pressure Lightweight Thrusters  

NASA Technical Reports Server (NTRS)

Returning samples of Martian soil and rock to Earth is of great interest to scientists. There were numerous studies to evaluate Mars Sample Return (MSR) mission architectures, technology needs, development plans, and requirements. The largest propulsion risk element of the MSR mission is the Mars Ascent Vehicle (MAV). Along with the baseline solid-propellant vehicle, liquid propellants have been considered. Similar requirements apply to other lander ascent engines and reaction control systems. The performance of current state-ofthe- art liquid propellant engines can be significantly improved by increasing both combustion temperature and pressure. Pump-fed propulsion is suggested for a single-stage bipropellant MAV. Achieving a 90-percent stage propellant fraction is thought to be possible on a 100-kg scale, including sufficient thrust for lifting off Mars. To increase the performance of storable bipropellant rocket engines, a high-pressure, lightweight combustion chamber was designed. Iridium liner electrodeposition was investigated on complex-shaped thrust chamber mandrels. Dense, uniform iridium liners were produced on chamber and cylindrical mandrels. Carbon/carbon composite (C/C) structures were braided over iridium-lined mandrels and densified by chemical vapor infiltration. Niobium deposition was evaluated for forming a metallic attachment flange on the carbon/ carbon structure. The new thrust chamber was designed to exceed state-of-the-art performance, and was manufactured with an 83-percent weight savings. High-performance C/Cs possess a unique set of properties that make them desirable materials for high-temperature structures used in rocket propulsion components, hypersonic vehicles, and aircraft brakes. In particular, more attention is focused on 3D braided C/Cs due to their mesh-work structure. Research on the properties of C/Cs has shown that the strength of composites is strongly affected by the fiber-matrix interfacial bonding, and that weakening interface realizes pseudo-plastic behavior with significant increase in the tensile strength. The investigation of high-temperature strength of C/Cs under high-rate heating (critical for thrust chambers) shows that tensile and compression strength increases from 70 MPa at room temperature to 110 MPa at 1,773 K, and up to 125 MPa at 2,473 K. Despite these unique properties, the use of C/Cs is limited by its high oxidation rate at elevated temperatures. Lining carbon/carbon chambers with a thin layer of iridium or iridium and rhenium is an innovative way to use proven refractory metals and provide the oxidation barrier necessary to enable the use of carbon/ carbon composites. Due to the lower density of C/Cs as compared to SiC/SiC composites, an iridium liner can be added to the C/C structure and still be below the overall thruster weight. Weight calculations show that C/C, C/C with 50 microns of Ir, and C/C with 100 microns of Ir are of less weight than alternative materials for the same construction.

Holmes, Richard; McKechnie, Timothy; Shchetkovskiy, Anatoliy; Smirnov, Alexander

2013-01-01

123

High pressure superconductivity of silicon  

NASA Astrophysics Data System (ADS)

We report detailed investigations of the superconducting properties of silicon in its high-pressure ?-Sn and primitive hexagonal (ph) phases. Resistivity measurements have been performed on two single crystals of p-type silicon (?10 16 cm -3, ?(300)?0.5 ohms cm) using an improved Bridgman-type device, with sintered-diamond anvils. In both phases, silicon is superconducting. In the ?-Sn modification (Si II), we find Tc=6.3K with a very small value of d Tc/ dP, in good agreement with earlier results. In the hexagonal phase (Si V), Tc, goes through a maximum at 2.8. K near the II/V phase boundary, then steadily decreases down to 3.6 K at 25 GPa. Comparison is made to the calculations of Chang et al. The theory correctly predicts the decrease of Tc in the ph phase. A reasonable agreement is also found between the calculated superconducting and those deduced from the experimental Tc's.

Mignot, J. M.; Chouteau, G.; Martinez, G.

1985-12-01

124

High Pressure-High Temperature Decomposition of Cyclotrimethylene Trinitramine  

E-print Network

High Pressure-High Temperature Decomposition of Cyclotrimethylene Trinitramine Zbigniew A. Dreger of -cyclotrimethylene trinitramine (-RDX) under high pressure-high temperature conditions was examined to elucidate in a diamond anvil cell (DAC) at pressures from 6 to 12 GPa and temperatures up to 600 K. Global decomposition

McCluskey, Matthew

125

High pressure pulsed capillary viscometry  

NASA Technical Reports Server (NTRS)

An analytical and test program was conducted in order to establish the feasibility of a multichamber pulsed-capillary viscometer. The initial design incorporated a piston, ram, and seals which produced measured pulses up to 30,000 psi in the closed chamber system. Pressure pulses from one to ten milliseconds were investigated in a system volume of 1 cuin. Four test fluids: a MIL-L-7808, a 5P4E polyphenyl ether, a MIL-L-23699A, and a synthetic hydrocarbon were examined in the test pressure assembly. The pressure-viscosity coefficient and viscosity delay time were determined for the MIL-L-7808 lubricant tested.

Smith, R. L.; Walowitt, J. A.; Pan, C. H. T.

1972-01-01

126

High pressure synthesis gas conversion. Final report  

SciTech Connect

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

Not Available

1993-05-01

127

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

Code of Federal Regulations, 2010 CFR

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

2010-10-01

128

33 CFR 149.550 - What are the requirements for lights on a floating hose string?  

Code of Federal Regulations, 2011 CFR

...false What are the requirements for lights on a floating hose string? 149...AND EQUIPMENT Aids to Navigation Lights on Floating Hose Strings § 149.550 What are the requirements for lights on a floating hose string?...

2011-07-01

129

33 CFR 149.550 - What are the requirements for lights on a floating hose string?  

Code of Federal Regulations, 2012 CFR

...false What are the requirements for lights on a floating hose string? 149...AND EQUIPMENT Aids to Navigation Lights on Floating Hose Strings § 149.550 What are the requirements for lights on a floating hose string?...

2012-07-01

130

33 CFR 149.550 - What are the requirements for lights on a floating hose string?  

Code of Federal Regulations, 2013 CFR

...false What are the requirements for lights on a floating hose string? 149...AND EQUIPMENT Aids to Navigation Lights on Floating Hose Strings § 149.550 What are the requirements for lights on a floating hose string?...

2013-07-01

131

33 CFR 149.550 - What are the requirements for lights on a floating hose string?  

Code of Federal Regulations, 2014 CFR

...false What are the requirements for lights on a floating hose string? 149...AND EQUIPMENT Aids to Navigation Lights on Floating Hose Strings § 149.550 What are the requirements for lights on a floating hose string?...

2014-07-01

132

High Precision Pressure Measurement with a Funnel  

ERIC Educational Resources Information Center

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

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

2008-01-01

133

High voltage grounding device for pressurized equipment  

Microsoft Academic Search

A safety device is described for discharging high voltage circuits operated in pressurized containers. The device is positioned in pressurized containers. The device is positioned within an elbow or other protrusion through which passes the high voltage feed-through electrode. In one embodiment the grounding contact is automatically forced against the high voltage contact by the expansion of a bellows upon

J. W. Ogland

1985-01-01

134

NETL- High-Pressure Combustion Research Facility  

SciTech Connect

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

2013-07-08

135

Gas Viscosity at High Pressure and High Temperature  

E-print Network

, very few investigations were performed on viscosity of naturally occurring gases, especially gas condensates at low-intermediate pressure and temperature, even fewer lab data were published. No gas viscosity data at high pressures and high temperatures...

Ling, Kegang

2012-02-14

136

Header-platen high-pressure heaters  

NASA Astrophysics Data System (ADS)

We present a new schematic design of high-pressure heaters for the regeneration systems of turbine units used at nuclear and thermal power stations, which features better reliability, smaller weight and overall dimensions, and higher thermal efficiency as compared with those characteristic for the design of the well-known types of heaters. We also show that it is possible to construct heaters for high pressures typical for supercritical-pressure boilers with the use of existing domestically made materials.

Avdeev, A. A.; Shamarokov, A. S.; Fal'Kovskii, L. N.

2009-02-01

137

Microbial inactivation by high-pressure  

Microsoft Academic Search

High-pressure treatments are receiving a great deal of attention for the inactivation of micro-organisms in foodstuff processing, pressure instead of temperature is used as stabilizing factor. In this context, high hydrostatic pressure treatment is the most studied alternative process, many works reported successful results in inactivating a wide range of micro-organisms under different operative conditions such as temperature, cycles of

S Spilimbergo; N Elvassore; A Bertucco

2002-01-01

138

Micronization of Insulin by High Pressure Homogenization  

Microsoft Academic Search

Purpose  The aim of this study was to establish the high pressure homogenization of proteins in non-aqueous suspension as an alternative method for classical micronization strategies and to investigate the effect of high pressure on protein stability and bioactivity.Methods  The influence of drug loading, homogenization pressure and cycles on particle size reduction was investigated by experimental design using a Box Behnken matrix

Angelika Maschke; Nadia Calí; Bernhard Appel; Josef Kiermaier; Torsten Blunk; Achim Göpferich

2006-01-01

139

What Are the Signs and Symptoms of High Blood Pressure?  

MedlinePLUS

... Are the Signs and Symptoms of High Blood Pressure? High blood pressure (HBP) itself usually has no ... for related health problems. Complications of High Blood Pressure When blood pressure stays high over time, it ...

140

DASH diet to lower high blood pressure  

MedlinePLUS

... Stop Hypertension. The DASH diet can help lower high blood pressure and cholesterol and other fats in your blood. ... The DASH diet reduces high blood pressure by lowering the amount of salt in your diet to 2,300 milligrams (mg) a day. Lowering salt to 1, ...

141

Frontiers of high-pressure research  

Microsoft Academic Search

This book is the result of a workshop held in l991 to summarize the most recent results in the field of high pressure research. The role of high pressure experiments in the discovery of superconducting materials with a T[sub c] above liquid nitrogen temperature has demonstrated the importance of such experiments. The same role holds true in the tailoring of

H. D. Hochheimer; R. D. Etters

1991-01-01

142

Vaporizing high pressure fluids: Energy release comparisons  

SciTech Connect

This paper utilizes a method previously presented for estimating potential energy which might be released as a shock wave from sudden failure of vessels containing fluids at high pressure supercritical conditions. Data are presented for several fluids and comparisons are made illustrating the relative hazard of these fluids at a typical condition of high pressure and temperature.

Aggarwal, M.C. [Gannon Univ., Erie, PA (United States); Fryer, D.M. [High Pressure Engineering and Safety, Fairview, PA (United States)

1995-11-01

143

HIGH PRESSURE CRYOCOOLING FOR MACROMOLECULAR CRYSTALLOGRAPHY  

E-print Network

high-pressure cryocooled and excellent crystal diffraction has been obtained without adding any. After achieving his B.S. degree in 1999, he spent 26 months in Korean Army as a medic. Then he enteredHIGH PRESSURE CRYOCOOLING FOR MACROMOLECULAR CRYSTALLOGRAPHY A Dissertation Presented

Gruner, Sol M.

144

High frequency dynamic pressure calibration technique  

NASA Astrophysics Data System (ADS)

A high frequency dynamic calibration technique for pressure transducers has been developed using a siren pressure generator (SPG). The SPG is an inlet-area-modulated device generating oscillating waveforms with dynamic pressure amplitudes up to 58.6 kPa (8.5 psi) in a frequency range of 1 to 10 kHz. A description of the generator, its operating characteristics and instrumentation used for pressure amplitude and frequency measurements is given. Waveform oscillographs and spectral analysis of the pressure transducers' output signals are presented.

Davis, P. A.; Zasimowich, R. F.

145

Structural behaviour of YGa under high pressure  

NASA Astrophysics Data System (ADS)

High pressure X-ray diffraction studies on rare-earth gallide YGa was carried up to a pressure of ˜ 33 GPa using rotating anode x-ray source in an angle dispersive mode. YGa exhibits CrB (B33) type orthorhombic structure (space group Cmcm) at ambient pressure. It undergoes a reversible structural phase transition from orthorhombic to tetragonal structure at ˜ 8.8 GPa. Both the phases coexist up to the highest pressure studied. The zero pressure bulk modulus and its derivative for parent phase have been estimated to be Bo = 60 ± 3 GPa, Bo' = 4.6 ± 1.5.

Sekar, M.; Shekar, N. V. Chandra; Sahu, P. Ch.; Babu, R.

2014-04-01

146

Structural behaviour of YGa under high pressure  

SciTech Connect

High pressure X-ray diffraction studies on rare-earth gallide YGa was carried up to a pressure of ? 33 GPa using rotating anode x-ray source in an angle dispersive mode. YGa exhibits CrB (B33) type orthorhombic structure (space group Cmcm) at ambient pressure. It undergoes a reversible structural phase transition from orthorhombic to tetragonal structure at ? 8.8 GPa. Both the phases coexist up to the highest pressure studied. The zero pressure bulk modulus and its derivative for parent phase have been estimated to be B{sub o} = 60 ± 3 GPa, B{sub o}' = 4.6 ± 1.5.

Sekar, M., E-mail: sekarm@igcar.gov.in; Shekar, N. V. Chandra, E-mail: sekarm@igcar.gov.in; Sahu, P. Ch., E-mail: sekarm@igcar.gov.in [Condensed Matter Physics Division, Materials Science Group, Indira Gandhi Centre for Atomic Research, Kalpakkam- 603 102 Tamil Nadu (India); Babu, R. [Fuel Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam- 603 102 Tamil Nadu (India)

2014-04-24

147

Design optimization of high pressure and high temperature piezoresistive pressure sensor for high sensitivity.  

PubMed

This paper describes a design method for optimizing sensitivity of piezoresistive pressure sensor in high-pressure and high-temperature environment. In order to prove the method, a piezoresistive pressure sensor (HPTSS) is designed. With the purpose of increasing sensitivity and to improve the measurement range, the piezoresistive sensor adopts rectangular membrane and thick film structure. The configuration of piezoresistors is arranged according to the characteristic of the rectangular membrane. The structure and configuration of the sensor chip are analyzed theoretically and simulated by the finite element method. This design enables the sensor chip to operate in high pressure condition (such as 150 MPa) with a high sensitivity and accuracy. The silicon on insulator wafer is selected to guarantee the thermo stability of the sensor chip. In order to optimize the fabrication and improve the yield of production, an electric conduction step is devised. Series of experiments demonstrates a favorable linearity of 0.13% and a high accuracy of 0.48%. And the sensitivity of HTPSS is about six times as high as a conventional square-membrane sensor chip in the experiment. Compared with the square-membrane pressure sensor and current production, the strength of HPTTS lies in sensitivity and measurement. The performance of the HPTSS indicates that it could be an ideal candidate for high-pressure and high-temperature sensing in real application. PMID:24517800

Niu, Zhe; Zhao, Yulong; Tian, Bian

2014-01-01

148

46 CFR 181.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2012 CFR

...Shipping 7 2012-10-01 2012-10-01 false Fire hoses and nozzles. 181.320 Section 181.320...SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) FIRE PROTECTION EQUIPMENT Fire Main System § 181.320 Fire hoses and...

2012-10-01

149

46 CFR 118.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2013 CFR

...Shipping 4 2013-10-01 2013-10-01 false Fire hoses and nozzles. 118.320 Section 118.320...OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fire Main System § 118.320 Fire hoses and...

2013-10-01

150

46 CFR 108.425 - Fire hoses and associated equipment.  

Code of Federal Regulations, 2014 CFR

...Shipping 4 2014-10-01 2014-10-01 false Fire hoses and associated equipment. 108.425 Section...A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Main System § 108.425 Fire hoses and...

2014-10-01

151

46 CFR 108.425 - Fire hoses and associated equipment.  

Code of Federal Regulations, 2010 CFR

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

2010-10-01

152

46 CFR 118.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2012 CFR

...Shipping 4 2012-10-01 2012-10-01 false Fire hoses and nozzles. 118.320 Section 118.320...OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fire Main System § 118.320 Fire hoses and...

2012-10-01

153

46 CFR 181.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2010 CFR

...Shipping 7 2010-10-01 2010-10-01 false Fire hoses and nozzles. 181.320 Section 181.320...SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) FIRE PROTECTION EQUIPMENT Fire Main System § 181.320 Fire hoses and...

2010-10-01

154

46 CFR 118.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2014 CFR

...Shipping 4 2014-10-01 2014-10-01 false Fire hoses and nozzles. 118.320 Section 118.320...OVERNIGHT ACCOMMODATIONS FOR MORE THAN 49 PASSENGERS FIRE PROTECTION EQUIPMENT Fire Main System § 118.320 Fire hoses and...

2014-10-01

155

46 CFR 181.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2014 CFR

...Shipping 7 2014-10-01 2014-10-01 false Fire hoses and nozzles. 181.320 Section 181.320...SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) FIRE PROTECTION EQUIPMENT Fire Main System § 181.320 Fire hoses and...

2014-10-01

156

46 CFR 118.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2010 CFR

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

2010-10-01

157

46 CFR 108.425 - Fire hoses and associated equipment.  

Code of Federal Regulations, 2011 CFR

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

2011-10-01

158

46 CFR 181.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2011 CFR

...Shipping 7 2011-10-01 2011-10-01 false Fire hoses and nozzles. 181.320 Section 181.320...SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) FIRE PROTECTION EQUIPMENT Fire Main System § 181.320 Fire hoses and...

2011-10-01

159

46 CFR 108.425 - Fire hoses and associated equipment.  

Code of Federal Regulations, 2012 CFR

...Shipping 4 2012-10-01 2012-10-01 false Fire hoses and associated equipment. 108.425 Section...A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Main System § 108.425 Fire hoses and...

2012-10-01

160

46 CFR 118.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2011 CFR

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

2011-10-01

161

46 CFR 181.320 - Fire hoses and nozzles.  

Code of Federal Regulations, 2013 CFR

...Shipping 7 2013-10-01 2013-10-01 false Fire hoses and nozzles. 181.320 Section 181.320...SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) FIRE PROTECTION EQUIPMENT Fire Main System § 181.320 Fire hoses and...

2013-10-01

162

46 CFR 108.425 - Fire hoses and associated equipment.  

Code of Federal Regulations, 2013 CFR

...Shipping 4 2013-10-01 2013-10-01 false Fire hoses and associated equipment. 108.425 Section...A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Main System § 108.425 Fire hoses and...

2013-10-01

163

49 CFR 571.106 - Standard No. 106; Brake hoses.  

Code of Federal Regulations, 2012 CFR

...around the cylinder. In the case of hose shorter than the circumference of the cylinder, bend the hose so that as much of its length...applied force is perpendicular to the tangent of the specimen circumference at the line of separation. (c) The rate of...

2012-10-01

164

49 CFR 571.106 - Standard No. 106; Brake hoses.  

Code of Federal Regulations, 2011 CFR

...around the cylinder. In the case of hose shorter than the circumference of the cylinder, bend the hose so that as much of its length...applied force is perpendicular to the tangent of the specimen circumference at the line of separation. (c) The rate of...

2011-10-01

165

49 CFR 571.106 - Standard No. 106; Brake hoses.  

Code of Federal Regulations, 2013 CFR

...around the cylinder. In the case of hose shorter than the circumference of the cylinder, bend the hose so that as much of its length...applied force is perpendicular to the tangent of the specimen circumference at the line of separation. (c) The rate of...

2013-10-01

166

Laser techniques in high-pressure geophysics  

NASA Technical Reports Server (NTRS)

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

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

1987-01-01

167

Catalytic high pressure synthesis of hindered ?-aminoesters  

Microsoft Academic Search

Hindered ?-aminoesters are obtained in fair to high yields by the conjugate addition of amines to ?,?-unsaturated esters, both substrates harbouring bulky groups, under high pressure in the presence of catalytic amounts of ytterbium triflate.

Gérard Jenner

1995-01-01

168

PARTICLE COLLECTION IN CYCLONES AT HIGH TEMPERATURE AND HIGH PRESSURE  

EPA Science Inventory

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

169

Abnormally high formation pressures, Potwar Plateau, Pakistan  

USGS Publications Warehouse

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

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

1998-01-01

170

Combustion of liquid sprays at high pressures  

NASA Technical Reports Server (NTRS)

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

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

1977-01-01

171

High-pressure mechanical instability in rocks  

USGS Publications Warehouse

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

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

1969-01-01

172

HIGH-TEMPERATURE AND HIGH-PRESSURE PARTICULATE CONTROL REQUIREMENTS  

EPA Science Inventory

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

173

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

E-print Network

Know Your Blood Pressure Many people with diabetes also have high blood pressure. Blood pressure is to keep the second number 80 or less. If either number is too high, you have high blood pressure. The first number is the pressure when your heart pumps. #12; Most people have high blood pressure because

174

High-pressure-activated carbon tetrachloride decomposition  

NASA Astrophysics Data System (ADS)

The pressure-induced molecular dissociation as one of the fundamental problems in physical sciences has aroused many theoretical and experimental studies. Here, using a newly developed particle swarm optimization algorithm, we investigate the high-pressure-induced molecular dissociation. The results show that the carbon tetrachloride (CCl4) is unstable and dissociates into C2Cl6 and Cl2 under approximately 120 GPa and more. The dissociation is confirmed by the lattice dynamic calculations and electronic structure of the Pa3 structure with pressure evolution. The dissociation pressure is far larger than that in the case of high temperature, indicating that the temperature effectively reduces the activation barrier of the dissociation reaction of CCl4. This research improves the understanding of the dissociation reactions of CCl4 and other halogen compounds under high pressures.

Chen, Yuan-Zheng; Zhou, Mi; Sun, Mei-Jiao; Li, Zuo-Wei; Sun, Cheng-Lin

2014-02-01

175

Frontiers of high-pressure research  

SciTech Connect

This book is the result of a workshop held in l991 to summarize the most recent results in the field of high pressure research. The role of high pressure experiments in the discovery of superconducting materials with a T[sub c] above liquid nitrogen temperature has demonstrated the importance of such experiments. The same role holds true in the tailoring of materials for optoelectronic devices. In addition, much progress has been made recently in the search for metallic hydrogen, and the application of high pressure in polymer research has brought forth interesting results. Separate abstracts have been prepared for papers in this book.

Hochheimer, H.D.; Etters, R.D. (eds.)

1991-01-01

176

Small, high-pressure liquid hydrogen turbopump  

NASA Technical Reports Server (NTRS)

A high pressure, liquid hydrogen turbopump was designed, fabricated, and tested to a maximum speed of 9739 rad/s and a maximum pump discharge pressure of 2861 N/sq. cm. The approaches used in the analysis and design of the turbopump are described, and fabrication methods are discussed. Data obtained from gas generator tests, turbine performance calibration, and turbopump testing are presented.

Csomor, A.; Sutton, R.

1977-01-01

177

49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Maximum allowable operating pressure: High-pressure distribution systems. 192.621 Section 192...Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems....

2012-10-01

178

49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Maximum allowable operating pressure: High-pressure distribution systems. 192.621 Section 192...Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems....

2013-10-01

179

49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Maximum allowable operating pressure: High-pressure distribution systems. 192.621 Section 192...Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems....

2010-10-01

180

49 CFR 192.621 - Maximum allowable operating pressure: High-pressure distribution systems.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Maximum allowable operating pressure: High-pressure distribution systems. 192.621 Section 192...Operations § 192.621 Maximum allowable operating pressure: High-pressure distribution systems....

2011-10-01

181

High Blood Pressure: The Science Inside  

NSDL National Science Digital Library

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

Healthy People Library Project

2004-01-01

182

High-pressure seals for rotary shafts  

NASA Technical Reports Server (NTRS)

High pressure seals for rotating shafts are machined from a polyimide resin. It is more durable and cheaper than the older seals of plastic coated metal and works at temperatures between - 400 degrees and plus 900 degrees f.

Holden, C. P.

1969-01-01

183

High-pressure studies of ammonia hydrates   

E-print Network

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

Wilson, Craig W.

2014-06-28

184

Preeclampsia and High Blood Pressure During Pregnancy  

MedlinePLUS

... mellitus , thrombophilia , or lupus • are obese • had in vitro fertilization What are the risks for my baby if ... red blood cells. Hypertension: High blood pressure. In Vitro Fertilization: A procedure in which an egg is removed ...

185

Elasticity of orthoenstatite at high-pressure  

NASA Astrophysics Data System (ADS)

Orthoenstatite is an abundant yet complex mineral in Earth's upper mantle. Despite its abundance, the properties of orthopyroxene at high pressure remain ambiguous (e.g., Zhang et al. 2011; Jahn 2008; Kung et al. 2004). We explored select properties of a synthetic powdered orthoenstatite (Mg0.8757Fe0.13)2Si2O6 sample by X-ray diffraction (XRD) and nuclear resonance inelastic X-ray scattering (NRIXS) as a function of pressure in a neon pressure medium at 300 K. The XRD measurements were carried out at beamline 12.2.2 of the Advanced Light Source (Berkeley, CA), and the sample was studied up to 34 GPa. NRIXS measurements were carried out at sector 3ID-B of the Advanced Photon Source (Chicago, IL) in the pressure range of 3 to 17 GPa. From the raw NRIXS data, the partial phonon density of states (DOS) was derived (e.g., Sturhahn 2004). The volume (or pressure) dependence of several properties, such as the Lamb-Mössbauer factor, mean force constant, specific heat, vibrational entropy, and vibrational kinetic energy were determined from the DOS. We will discuss our results from these combined studies and the implications for Earth's upper mantle. References Zhang, D., J.M. Jackson, W. Sturhahn, and Y. Xiao (2011): Local structure variations observed in orthoenstatite at high-pressures. American Mineralogist, in press. Jahn, S. (2008) High-pressure phase transitions in MgSiO3 orthoenstatite studied by atomistic computer simulation. American Mineralogist, 93(4), 528-532. Kung, J., Li, B., Uchida, T., Wang, Y., Neuville, D., and Liebermann, R. (2004) In situ measurements of sound velocities and densities across the orthopyroxene high-pressure clinopyroxene transition in MgSiO3 at high pressure. Physics of the Earth and Planetary Interiors, 147(1), 27-44. Sturhahn, W. (2004): Nuclear Resonant Spectroscopy. J. Phys. Condens. Matter, 16, S497-S530.

Zhang, D.; Jackson, J. M.; Chen, B.; Zhao, J.; Yan, J.

2011-12-01

186

Structures of Liquid Aluminium under High Pressure  

NASA Astrophysics Data System (ADS)

Molecular dynamics simulation has been carried out for melt Al under constant temperature and constant pressure. The interaction between atoms is described by tight-binding many-body potentials based on the second-moment approximation to the electronic density of states. The pair correlation function and the pair analysis technique are used to reveal the structural features of liquid Al under normal and high pressure. High pressure is favourable to the existence of bcc clusters 1661 and 1441, but has no effect on the fcc cluster 1421. The bond pair 1551 and 1541 with fivefold symmetry exists at high pressure. The microstructure of liquid is more similar to the non-crystalline structure than to the crystalline structure. The simulation results are supported by the x-ray experimental results.

Li, Hui; Wang, Guang-Hou; Bian, Xiu-Fang; Zhang, Lin

2001-04-01

187

High pressure ceramic heat exchanger  

DOEpatents

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.

1998-09-22

188

High pressure ceramic heat exchanger  

DOEpatents

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)

1999-01-01

189

High pressure ceramic heat exchanger  

DOEpatents

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)

1998-01-01

190

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

PubMed

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

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

2003-01-01

191

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

NASA Astrophysics Data System (ADS)

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

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

2003-01-01

192

Dimerization of boron triiodide at high pressure  

NASA Astrophysics Data System (ADS)

High-pressure phase transition of boron triiodide (BI3) is investigated using first-principles methods, with the crystal structure of the high-pressure phase predicted. The structure is consistent with the information on this phase available from experiments. Significantly, the BI3 molecules are predicted to form B2I6 dimers that are structurally analogous to the D2h diborane molecules. Dimerization of BI3 molecules yields a notable volume drop that triggers a first-order phase transition. Using the predicted structure, the calculated equation of state, phase transition pressure, and the metallization transition pressure are in an excellent agreement with the experimental measurements. Dimerization in crystalline BI3 provides insight for the understanding of covalently bound boron halide dimers, which were previously unknown.

Yao, Yansun; Klug, Dennis D.; Marto?ák, Roman; Patchkovskii, Serguei

2011-06-01

193

Sample injector for high pressure liquid chromatography  

DOEpatents

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

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

2001-01-01

194

46 CFR 95.10-10 - Fire hydrants and hose.  

Code of Federal Regulations, 2013 CFR

...Shipping 4 2013-10-01 2013-10-01 false Fire hydrants and hose. 95.10-10 Section 95...CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 95.10-10 Fire...

2013-10-01

195

46 CFR 193.10-10 - Fire hydrants and hose.  

Code of Federal Regulations, 2011 CFR

...Shipping 7 2011-10-01 2011-10-01 false Fire hydrants and hose. 193.10-10 Section 193...CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 193.10-10 Fire...

2011-10-01

196

46 CFR 193.10-10 - Fire hydrants and hose.  

Code of Federal Regulations, 2014 CFR

...Shipping 7 2014-10-01 2014-10-01 false Fire hydrants and hose. 193.10-10 Section 193...CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 193.10-10 Fire...

2014-10-01

197

46 CFR 95.10-10 - Fire hydrants and hose.  

Code of Federal Regulations, 2012 CFR

...Shipping 4 2012-10-01 2012-10-01 false Fire hydrants and hose. 95.10-10 Section 95...CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 95.10-10 Fire...

2012-10-01

198

46 CFR 95.10-10 - Fire hydrants and hose.  

Code of Federal Regulations, 2011 CFR

...Shipping 4 2011-10-01 2011-10-01 false Fire hydrants and hose. 95.10-10 Section 95...CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 95.10-10 Fire...

2011-10-01

199

46 CFR 193.10-10 - Fire hydrants and hose.  

Code of Federal Regulations, 2012 CFR

...Shipping 7 2012-10-01 2012-10-01 false Fire hydrants and hose. 193.10-10 Section 193...CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 193.10-10 Fire...

2012-10-01

200

46 CFR 95.10-10 - Fire hydrants and hose.  

Code of Federal Regulations, 2014 CFR

...Shipping 4 2014-10-01 2014-10-01 false Fire hydrants and hose. 95.10-10 Section 95...CONTINUED) CARGO AND MISCELLANEOUS VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 95.10-10 Fire...

2014-10-01

201

46 CFR 193.10-10 - Fire hydrants and hose.  

Code of Federal Regulations, 2013 CFR

...Shipping 7 2013-10-01 2013-10-01 false Fire hydrants and hose. 193.10-10 Section 193...CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 193.10-10 Fire...

2013-10-01

202

Restoration Algorithms for Virtual Private Networks in the Hose Model  

E-print Network

Restoration Algorithms for Virtual Private Networks in the Hose Model Giuseppe F. Italiano, Rajeev: italiano@disp.uniroma2.it. URL: http://www.info.uniroma2.it/¨italiano. Part of this work was done while

Yener, Bülent

203

29 CFR 1910.158 - Standpipe and hose systems.  

Code of Federal Regulations, 2010 CFR

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

2010-07-01

204

ALTERNATIVES FOR HIGH-TEMPERATURE/HIGH-PRESSURE PARTICULATE CONTROL  

EPA Science Inventory

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

205

High Blood Pressure and Metabolic Syndrome  

MedlinePLUS

... had twice the risk for high blood pressure, metabolic syndrome and diabetes than those who were highly fit. The risk ... they have to reduce their risk for the metabolic syndrome, heart disease, diabetes and stroke. This content was last reviewed on ...

206

High-temperature high-pressure magnetic pickup  

NASA Technical Reports Server (NTRS)

Magnetic-pickup transducers operate at temperature as high as 1,100 C and pressures in excess of 2.5 kilobars. Transducers obtain simulated seismic data in laboratory experiments at high temperatures and pressure. They also have potential applications in industrial instrumentation for measurements under similarly difficult conditions. Transducers use high-temperature cement to bond parts together and high-temperature-insulated copper or aluminum wire for windings.

Ahlberg, L. A.; Tittmann, B. R.

1980-01-01

207

Effect of High Pressure on Uranyl Nanocages  

NASA Astrophysics Data System (ADS)

Uranyl nanocages U24Py12, U60, and U24 were studied in situ at high pressure in order to understand the response of these structures to pressure. Single crystals of the nanocage structures were analyzed by in situ Raman spectroscopy, synchrotron X-ray diffraction and small angle X-Ray scattering in diamond anvil cells, as well as electrospray ionization mass spectrometry. At ambient pressure conditions, U24Py12 is tetragonal (P42/mnm: a = 22.746(2) Å, c = 30.426(4) Å), U60 is isometric (Fm-3: a=37.884(2) Å), and U24 is triclinic (P1-: a=19.2111(11), b=31.003(2), c=32.252(2), ?=102.404(4)°, ?=99.506(4) °, ?=95.362(4) °). Pressures ranged from ambient to 50 GPa; single crystals less than 200 microns in diameter were used. Two symmetric stretch modes of the uranyl ion are evident in the Raman spectra of all three nanocages with Raman shifts of 810 and 830 cm-1. The modes are clearly evident at pressures ranging from ambient to 4-8 GPa. At pressures higher than this range, the uranyl ion vibrational mode broadens further and shifts to higher stretching frequencies. The signal for U60 is irreversibly lost at 17 GPa, but for U24 and U24Py12, the signal persists and continues to broaden at pressures up to 50 GPa. After pressure quenching, there was still no signal from the U60, but U24 and U24Py12 both show one broad Raman mode at 840 cm-1. High pressure synchrotron X-ray diffraction measurements were completed at Argonne National Laboratory to quantify structural unit cell changes over the pressure ranges investigated. U24Py12 undergoes a phase transition to higher symmetry at approximately 5 GPa, and eventually partially amorphizes at 17 GPa, irreversibly. U60 undergoes a phase transition from isometric to tetragonal at 4.4 GPa, and amorphizes irreversibly at 10 GPa. Small angle X-ray scattering measurements show that the cluster topology is maintained even after amorphization of U24Py12 and U60. Mass spectrometry data indicate that these clusters remain intact at high pressures, despite the loss of long-range periodicity. These experiments provide insight into the stability of different types of uranyl nanocages, as well the relation between cluster topology and stability with increasing pressure.

Turner, K. M.; Zhang, F.; Pellegrini, K.; McGrail, B. T.; Burns, P. C.; Ewing, R. C.

2013-12-01

208

High Temperature Dynamic Pressure Measurements Using Silicon Carbide Pressure Sensors  

NASA Technical Reports Server (NTRS)

Un-cooled, MEMS-based silicon carbide (SiC) static pressure sensors were used for the first time to measure pressure perturbations at temperatures as high as 600 C during laboratory characterization, and subsequently evaluated in a combustor rig operated under various engine conditions to extract the frequencies that are associated with thermoacoustic instabilities. One SiC sensor was placed directly in the flow stream of the combustor rig while a benchmark commercial water-cooled piezoceramic dynamic pressure transducer was co-located axially but kept some distance away from the hot flow stream. In the combustor rig test, the SiC sensor detected thermoacoustic instabilities across a range of engine operating conditions, amplitude magnitude as low as 0.5 psi at 585 C, in good agreement with the benchmark piezoceramic sensor. The SiC sensor experienced low signal to noise ratio at higher temperature, primarily due to the fact that it was a static sensor with low sensitivity.

Okojie, Robert S.; Meredith, Roger D.; Chang, Clarence T.; Savrun, Ender

2014-01-01

209

High pressure and high temperature behaviour of ZnO  

SciTech Connect

The thermodynamic properties with the wurtzite (B4) and rocksalt (B1) phases of ZnO under high pressures and high temperatures have been investigated using Tait's Equation of state (EOS). The effects of pressures and temperatures on thermodynamic properties such as bulk modulus, thermal expansivity and thermal pressure are explored for both two structures. It is found that ZnO material gradually softens with increase of temperature while it hardens with the increment of the pressure. Our predicted results of thermodynamics properties for both the phases of ZnO are in overall agreement with the available data in the literature.

Thakar, Nilesh A. [K. K. Shah Jarodwala Maninagar Science College, Rambaug, Maninagar, Ahmedabad-380008 (India); Bhatt, Apoorva D. [Department of Physics, Gujarat University, Ahmedabad-380009 (India); Pandya, Tushar C., E-mail: pandyatc@gmail.com [St. Xavier's College, Navrangpura, Ahmedabad-380009 (India)

2014-04-24

210

76 FR 38697 - High Pressure Steel Cylinders From China  

Federal Register 2010, 2011, 2012, 2013, 2014

...731-TA-1188; Preliminary] High Pressure Steel Cylinders From China Determinations...reason of imports from China of high pressure steel cylinders, provided for in subheading...of LTFV and subsidized imports of high pressure steel cylinders from China....

2011-07-01

211

77 FR 37712 - High Pressure Steel Cylinders From China  

Federal Register 2010, 2011, 2012, 2013, 2014

...and 731-TA-1188 (Final)] High Pressure Steel Cylinders From China Determinations...injured by reason of imports of high pressure steel cylinders from China, provided...determinations by Commerce that imports of high pressure steel cylinders from China were...

2012-06-22

212

Over-the-Counter Medications and High Blood Pressure  

MedlinePLUS

... all of our regular issues. Interactive High Blood Pressure Guide Find videos, quizzes, trackers and more with ... Also available as a downloadable PDF . High Blood Pressure • Home • About High Blood Pressure (HBP) • Why HBP ...

213

High pressure chemistry of substituted acetylenes  

SciTech Connect

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

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

2011-01-25

214

High pressure water jet mining machine  

DOEpatents

A high pressure water jet mining machine for the longwall mining of coal is described. The machine is generally in the shape of a plowshare and is advanced in the direction in which the coal is cut. The machine has mounted thereon a plurality of nozzle modules each containing a high pressure water jet nozzle disposed to oscillate in a particular plane. The nozzle modules are oriented to cut in vertical and horizontal planes on the leading edge of the machine and the coal so cut is cleaved off by the wedge-shaped body.

Barker, Clark R. (Rolla, MO)

1981-05-05

215

Raman study of opal at high pressure  

NASA Astrophysics Data System (ADS)

More commonly known for their beauty and lore as gemstones, opals are also intriguing geological materials which may have potential for materials science applications. Opal lacks a definite crystalline structure, and is composed of an amorphous packing of hydrated silica (SiO2) spheroids, which provides us with a unique nano-scaled mineraloid with properties unlike those of other amorphous materials like glass. Opals from different localities were studied at high pressure using a diamond anvil cell to apply pressure and Raman spectroscopy to look at changes in bonding as pressure was increased. We first tested different samples from Virgin Valley, NV, Spencer, ID, Juniper Ridge, OR, and Australia, which contain varying amounts of water at ambient conditions, using Raman spectroscopy to determine if they were opal-CT (semicrystalline cristobalite-trydimite volcanic origin) or opal-A (amorphous sedimentary origin). We then used x-ray diffraction and Raman spectroscopy in a diamond anvil cell to see how their bonding and structure changed under compression and to determine what effect water content had on their high pressure behavior. Comparison of our results on opal to other high pressure studies of amorphous materials like glass has implications from a geological and materials science standpoint.

Farfan, G.; Wang, S.; Mao, W. L.

2011-12-01

216

HIGH PRESSURE COAL COMBUSTON KINETICS PROJECT  

SciTech Connect

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

2005-03-30

217

Advanced Diagnostics for High Pressure Spray Combustion.  

SciTech Connect

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.

2014-06-01

218

A high sensitivity resonator pressure sensor  

Microsoft Academic Search

We propose a new resonator pressure sensor using shallow shells. The sensor has high sensitivity due to the shallow shell structure. A theoretical analysis is performed using the theory for small fields superposed on finite biasing fields in an elastic body. The analysis shows that shallow shells have a magnifying effect on sensor sensitivity. Sensitivity of a quartz plate thickness-shear

J. S. Yang; X. Zhang

2002-01-01

219

Hurricane risk mitigation - High Pressure Gas Facility  

NASA Technical Reports Server (NTRS)

A worker pours concrete as part of a nitrogen risk mitigation project at the High Pressure Gas Facility at Stennis Space Center. The concrete slab will provide the foundation needed to place new pumps at the site and is part of ongoing hurricane-related mitigation work at Stennis.

2008-01-01

220

High pressure studies of planetary matter  

SciTech Connect

Those materials which are of greatest interest to the physics of the deep planetary interiors are Fe, H/sub 2/, He and the Ices. These are sufficiently diverse and intensively studied to offer an overview of present day high pressure research. 13 refs., 1 fig.

Ross, M.

1989-06-01

221

High pressure discharges in cavities formed by microfabrication techniques  

Microsoft Academic Search

High pressure discharges are the basis of small high intensity light sources. In this work, we demonstrate the formation of high pressure discharges, in cavities formed by applying micromachining and integrated circuit techniques to quartz substrates. Cavities containing varying amounts of mercury and argon were fabricated to obtain high pressure discharges. A high pressure mercury discharge was formed in the

Babar A. Khan; David A. Cammack; Ronald D. Pinker; Jacqueline Racz

1997-01-01

222

Viscosities of natural gases at high pressures and high temperatures  

E-print Network

Estimation of viscosities of naturally occurring petroleum gases provides the information needed to accurately work out reservoir-engineering problems. Existing models for viscosity prediction are limited by data, especially at high pressures...

Viswanathan, Anup

2007-09-17

223

varicose veins smoking obesity swine flu high blood pressure  

E-print Network

varicose veins smoking obesity swine flu high blood pressure parkinson's stress depression muscle stiffness heart attack asthma low blood pressure alzheimer's cancer diabetes kidney failure dementia smoking obesity swine flu high blood pressure parkinson's stress depression muscle stiffness heart attack

Diggle, Peter J.

224

Who is at Risk for High Blood Pressure?  

MedlinePLUS

... Twitter. Who Is at Risk for High Blood Pressure? High blood pressure (HBP) is a common condition. ... This Content: Next >> Featured Video Myth-busting blood pressure - a hypertension Google+ hangout in honor of World ...

225

LHDAC setup for high temperature and high pressure studies  

SciTech Connect

A ytterbium fibre laser (? = 1.07 ?m) based laser heated diamond anvil cell (LHDAC) facility has been recently set up at HP and SRPD, BARC for simultaneous high temperature and high pressure investigation of material properties. Synthesis of GaN was carried out at pressure of ?9 GPa and temperature of ?1925 K in a Mao-Bell type diamond anvil cell (DAC) using the LHDAC facility. The retrieved sample has been characterized using our laboratory based micro Raman setup.

Patel, Nishant N., E-mail: nnpatel@barc.gov.in; Meenakshi, S., E-mail: nnpatel@barc.gov.in; Sharma, Surinder M., E-mail: nnpatel@barc.gov.in [High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai-400085 (India)

2014-04-24

226

High Pressure Study on Natural Chromite  

NASA Astrophysics Data System (ADS)

Spinel phase is generally found at crust and upper mantle. Moreover, spinel phase and its modified form play an important role at transition zone and therefore are geologically importance. Besides, spinel phase usually exhibits with solid-solution from a wide range of different size of cations and therefore study of the substation of cations within spinel structure and its high-pressure form are important to better understand the structure and evolution of the deep mantle. In this study, a natural chromite sample, a Cr-rich spinel and an important resource for chromium and iron, was investigated in a diamond anvil cell using synchrotron x-ray diffraction and Raman spectroscopy. In situ synchrotron x-ray diffraction was performed at GSECARS, Advance Photon Source and X17C, National Synchrotron Light Source. Our high-pressure x-ray diffraction study showed a new phase emerging at about 20 GPa which is slightly higher than previously reported transition pressure at about 12 GPa when using a synthetic chromite sample. Furthermore, our Raman study on chromite also did not observe any phase transition at 12 GPa. Instead, our Raman data shows several broad peaks at ambient and continuously observed at high pressures till 30 GPa. Above 30 GPa, the Raman signals of chromite showed new feature and became very weak. Our results suggest that the impurity within chromite may play a critical role for the phase transition.

Shieh, S. R.; Ali, W.; Xiong, Z.

2013-12-01

227

Small, high-pressure, liquid oxygen turbopump  

NASA Technical Reports Server (NTRS)

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

Csomor, A.

1978-01-01

228

Small, high-pressure liquid oxygen turbopump  

NASA Technical Reports Server (NTRS)

A small, high-pressure, liquid oxygen turbopump was designed, fabricated, and tested. The pump was of a single-stage, centrifugal type; power to the pump was supplied by a single-stage, partial emission, axial-impulse turbine. Design conditions included an operating speed of 70,000 rpm, pump discharge pressure of 2977 N/sq cm (4318 psia), and a pump flowrate of 16.4 kg/s (36.21 lb/sec). The turbine was propelled by LO2/LH2 combustion products at 1041 K (1874 R) inlet temperature, and at a design pressure ratio of 1.424. The approaches used in the detail analysis and design of the turbopump are described, and fabrication methods are discussed. Data obtained from gas generator tests, turbine performance calibration, and turbopump testing are presented.

Csomor, A.; Sutton, R.

1977-01-01

229

7 CFR 58.219 - High pressure pumps and lines.  

Code of Federal Regulations, 2010 CFR

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

2010-01-01

230

High pressure in solid-state chemistry Grard Demazeau  

E-print Network

1 High pressure in solid-state chemistry Gérard Demazeau 1. Introduction In solid-state chemistry, high pressures can be used in two different ways. The application of high pressures to existing with the compressibility of the solid. On the other hand, high pressures can play an important role in the synthesis of new

Boyer, Edmond

231

Keep the Beat: Control Your High Blood Pressure  

E-print Network

Keep the Beat: Control Your High Blood Pressure Healthy Hearts, Healthy Homes #12;Read other at www.nhlbi.nih.gov. #12;Keep the Beat: Control Your High Blood Pressure Delicious Heart Healthy Latino Homes #12;Keep the Beat: Control Your High Blood Pressure 1 Did you know that high blood pressure

Bandettini, Peter A.

232

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

E-print Network

Dynamics of Low-Pressure and High-Pressure Fuel Cell Air Supply System1 Sylvain Gelfi2 , Anna G 48109 Abstract Choosing an operating pressure is a critical decision that de- fines many characteristics of the fuel cell system. High stack power density is the main selling point of high-pressure sys- tems

Peng, Huei

233

High-pressure liquid chromatographic gradient mixer  

DOEpatents

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.

1982-09-08

234

Prediction of Production Power for High-pressure Hydrogen by High-pressure Water Electrolysis  

NASA Astrophysics Data System (ADS)

Recently the high attention for fuel cell electric vehicle (FCEV) is pushing to construct the hydrogen supplying station for FCEV in the world. The hydrogen pressure supplied at the current test station is intended to be high for increasing the FCEV’s driving distance. The water electrolysis can produce cleanly the hydrogen by utilizing the electricity from renewable energy without emitting CO2 to atmosphere, when it is compared to be the popular reforming process of fossil fuel in the industry. The power required for the high-pressure water electrolysis, where water is pumped up to high-pressure, may be smaller than the power for the atmospheric water electrolysis, where the produced atmospheric hydrogen is pumped up by compressor, since the compression power for water is much smaller than that for hydrogen gas. In this study the ideal water electrolysis voltage up to 70MPa and 523K is estimated referring to both the results by LeRoy et al up to 10MPa and 523K, and to the latest steam table. By using this high-pressure water electrolysis voltage, the power required for high-pressure hydrogen produced by the high-pressure water electrolysis method is estimated to be about 5% smaller than that by the atmospheric water electrolysis method, by assuming the compressor and pump efficiency of 50%.

Kyakuno, Takahiro; Hattori, Kikuo; Ito, Kohei; Onda, Kazuo

235

Cavity closure arrangement for high pressure vessels  

DOEpatents

A closure arrangement for a pressure vessel such as the pressure vessel of a high temperature gas-cooled reactor wherein a liner is disposed within a cavity penetration in the reactor vessel and defines an access opening therein. A closure is adapted for sealing relation with an annular mounting flange formed on the penetration liner and has a plurality of radially movable locking blocks thereon having outer serrations adapted for releasable interlocking engagement with serrations formed internally of the upper end of the penetration liner so as to effect high strength closure hold-down. In one embodiment, ramping surfaces are formed on the locking block serrations to bias the closure into sealed relation with the mounting flange when the locking blocks are actuated to locking positions.

Amtmann, Hans H. (San Diego, CA)

1981-01-01

236

High-pressure investigations of Earth's interior  

NASA Astrophysics Data System (ADS)

In the first half of the talk, the electronic structure of iron in ferromagnesium silicate perovskite will be discussed. Knowledge of iron valences and spin states in silicate perovskite is relevant to our understanding of the physical and chemical properties of Earth's lower mantle such as transport properties, mechanical behavior, and element partitioning. In this study, we have measured the electronic structure of the iron component of an aluminous Fe-bearing silicate perovskite sample, (Mg0.88Fe0.09)(Si0.94Al0.10)O3, close to a pyrolite composition, using synchrotron M"ossbauer spectroscopy (SMS) and laser heated diamond anvil cells at high-pressure and temperatures at beamline 3-ID of the Advanced Photon Source. Evaluation of the spectra provided the isomer shift and the quadrupole splitting of the iron component in silicate perovskite, which gives information on valence and spin states under lower mantle conditions. In the second half of the talk, experiments on the melting curve of iron at high-pressures will be presented. Seismological observations indicate that Earth's iron-dominated core consists of a solid inner region surrounded by a liquid outer core. Previously, melting studies of iron metal at high-pressures and temperatures were performed by shock-compression, resistive- and laser-heating in diamond anvil cells using visual observations or synchrotron x-ray diffraction and theoretical methods. However, the melting curve of iron is still controversial. Here, we will present a new method of detecting the solid-liquid phase boundary of iron at high-pressure using ^57Fe SMS. The characteristic SMS time signature is observed by fast detectors and vanishes suddenly when melting occurs. This process is described by the Lamb-M"ossbauer factor f = exp(-k^2), where k is the wave number of the resonant x-rays and is the mean-square displacement of the iron atoms.

Jackson, Jennifer

2007-03-01

237

Small, high pressure liquid hydrogen turbopump  

NASA Technical Reports Server (NTRS)

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

Csomor, A.; Warren, D. J.

1980-01-01

238

Phosphorescence in high-pressure synthetic diamond  

Microsoft Academic Search

Long-lived phosphorescence has been investigated in high-pressure synthetic boron-doped diamond. The spectrum exhibits two broad bands at peak energies of 2.1 and 2.5 eV after ultra-violet light excitation. The typical lifetime for both the bands shows a monotonous decrease from 50 s to 300 ms as the temperature rises from 200 to 400 K. The integrated intensities of the 2.1

Kenji Watanabe; Simon C. Lawson; Junichi Isoya; Hisao Kanda; Yoichro Sato

1997-01-01

239

Ion-hose instability in a long-pulse linear induction accelerator  

NASA Astrophysics Data System (ADS)

The ion-hose instability is a transverse electrostatic instability which occurs on electron beams in the presence of a low-density ion channel. It is a phenomenon quite similar to the interaction between electron clouds and proton or positron beams in high-energy accelerators and storage rings. In the DARHT-2 accelerator, the 2-kA, 2-?s beam pulse produces an ion channel through impact ionization of the residual background gas (10-7 10-6 torr). A calculation of the linear growth by Briggs indicates that the instability could be strong enough to affect the radiographic application of DARHT, which requires that transverse oscillations be small compared to the beam radius. We present semianalytical theory and 3D particle-in-cell simulations (using the Lsp code) of the linear and nonlinear growth of the instability, including the effects of the temporal change in the ion density and spatially decreasing beam radius. We find that the number of e-foldings experienced by a given beam slice is given approximately by an analytic expression using the local channel density at the beam slice. Hence, in the linear regime, the number of e-foldings increases linearly from head to tail of the beam pulse since it is proportional to the ion density. We also find that growth is strongly suppressed by nonlinear effects at relatively small oscillation amplitudes of the electron beam. This is because the ion oscillation amplitude is several times larger than that of the beam, allowing nonlinear effects to come into play. An analogous effect has recently been noted in electron-proton instabilities in high-energy accelerators and storage rings. For DARHT-2 parameters, we find that a pressure of ?1.5×10-7 torr is needed to keep the transverse beam oscillation amplitude less than about 20% of the rms beam radius.

Genoni, Thomas C.; Hughes, Thomas P.

2003-03-01

240

Apparatus and methods for splicing conduits and hoses subsea  

DOEpatents

A hose connection system comprises a body including an internal cavity and a port in fluid communication with a portion of the internal cavity. In addition, the system comprises a hose end fitting positioned in the cavity. The hose end fitting includes an inner tubular member and an outer tubular member concentrically disposed about the inner tubular member. The outer tubular member includes a plurality of circumferentially spaced axial slits. Further, the system comprises a plurality of wedge members arranged circumferentially about the outer tubular member. Still further, the system comprises an annular piston movably disposed within the internal cavity of the body. An end of the piston has an inner frustoconical surface that slidingly engages the plurality of wedge members. The piston is configured to move axially through the body and compress the wedge members and the outer tubular member radially inward.

Slocum, Alexander Henry; Gutierrez, Luis Javier

2014-03-11

241

High-Pressure Air Constituent Plasmas  

NASA Astrophysics Data System (ADS)

High-Pressure air plasmas are finding increasing application in plasma processing industry as plasma reactors, light sources, and biological decontaminants. One of the major issues particular to such plasma is the high radio-frequency power required to initiate and sustain the discharge. However, once the gas breakdown has occurred and the discharge is initiated, radio frequency power can be more efficiently absorbed by the plasma through inductive coupling of the wave fields. Mixing noble gasses with the air constituents and improving the gas flow can also reduce power requirements. A high-density 10^12 -10^14 cm-3, large volume plasma of air constituents (N_2, O_2, Air, and Argon mixtures) is created by either laser (300 mJ for 20() ns half- pulse width) preionization of an organic gas (2-6 mTorr) seeded in a high- pressure gas (760 Torr); or by high power (1-25 kW) pulsed rf sources in gas mixtures. The effect of gas flow on the discharge characteristics will be presented. A multi-turn helical antenna is used to couple rf power through a capacitive matching network. A 105 GHz interferometer is employed to obtain plasma density in the presence of high collisionality utilizing phase shift and amplitude attenuation. A Boltzmann plot of the emission spectrum is used to calculate the excitation temperature. Network analyzer measurements of the antenna impedance provide an ANTENNA-II code predicted density estimate

Akhtar, Kamran; Scharer, John E.; Tysk, Shane M.; White, Ben O.; Denning, C. Mark; Kho, Enny

2002-10-01

242

Prediction of production power for high-pressure hydrogen by high-pressure water electrolysis  

NASA Astrophysics Data System (ADS)

Recent attention focused on fuel cell electric vehicles (FCEVs) has created demand for the construction of hydrogen supply stations for FCEVs throughout the world. The hydrogen pressure supplied at the supply stations is intentionally high to increase the FCEVs driving mileage. Water electrolysis can produce clean hydrogen by utilizing electricity from renewable energy without CO 2 emission to the atmosphere when compared with the industrial fossil fuel reforming process. The power required for high-pressure water electrolysis, wherein water is pumped up to a high-pressure, may be less than the power required for atmospheric water electrolysis, wherein the produced atmospheric hydrogen is pumped by a compressor, since the compression power for water is much less than that for hydrogen-gas. In this study, the ideal water electrolysis voltage of up to 70 MPa and 250 °C is estimated by referring to both the results of LeRoy et al. up to 10 MPa and 250 °C, and the latest steam tables. Using this high-pressure water electrolysis voltage, the power required to produce high-pressure hydrogen by high-pressure water electrolysis is estimated to be about 5% less than that required for atmospheric water electrolysis, assuming compressor and pump efficiencies of 50%.

Onda, Kazuo; Kyakuno, Takahiro; Hattori, Kikuo; Ito, Kohei

243

Simulation of high pressure freezing processes by enthalpy method  

Microsoft Academic Search

High pressure freezing processes such as pressure assisted freezing (PAF) and high pressure shift freezing (HPSF) are novel technologies that can be used to improve the quality of frozen foods. A one dimensional finite difference numerical model based on the enthalpy formulation was developed to simulate high pressure freezing of tylose, agar gel and potatoes. The Schwartzberg equation was used

T. Norton; A. Delgado; E. Hogan; P. Grace; Da-Wen Sun

2009-01-01

244

Application of high pressure treatment for cheese production  

Microsoft Academic Search

High hydrostatic-pressure treatment offers the food industry a new technology for food preservation. Interest in high pressure application on milk has recently increased. Pressures between 300 and 600 MPa can inactivate microorganisms including most infectious food-borne pathogens. In addition to microbial destruction, it has been reported that high pressure improves rennet or acid coagulation of milk and increases cheese yield.

A. J Trujillo; M Capellas; M Buffa; C Royo; R Gervilla; X Felipe; E Sendra; J Saldo; V Ferragut; B Guamis

2000-01-01

245

Operating mode of high pressure straws with high spatial resolution  

NASA Astrophysics Data System (ADS)

The article presents results of studying the operating mode of thin-walled drift tubes (straws) at flushing it with a high-pressure gas mixture, which allowed obtaining extremely high spatial resolution for straw detectors. The results of studying the radiation ageing of straws operating in this mode are also described.

Davkov, K. I.; Myalkovskiy, V. V.; Peshekhonov, V. D.; Cholakov, V. D.

2014-05-01

246

A high frequency silicon pressure sensor  

NASA Technical Reports Server (NTRS)

Theoretical and design considerations as well as fabrication and experimental work involved in the development of high-frequency silicon pressure sensors with an ultra-small diaphragm are discussed. A sensor is presented with a rectangular diaphragm of 0.0127 cm x 0.0254 cm x 1.06 micron; the sensor has a natural frequency of 625 kHz and a sensitivity of 0.82 mv/v-psi. High-frequency results from shock tube testing and low-frequency (less than 50 kHz) comparison with microphones are given.

Kahng, S. K.; Gross, C.

1980-01-01

247

Very high-pressure orogenic garnet peridotites  

PubMed Central

Mantle-derived garnet peridotites are a minor component in many very high-pressure metamorphic terranes that formed during continental subduction and collision. Some of these mantle rocks contain trace amounts of zircon and micrometer-sized inclusions. The constituent minerals exhibit pre- and postsubduction microstructures, including polymorphic transformation and mineral exsolution. Experimental, mineralogical, petrochemical, and geochronological characterizations using novel techniques with high spatial, temporal, and energy resolutions are resulting in unexpected discoveries of new phases, providing better constraints on deep mantle processes. PMID:17519341

Liou, J. G.; Zhang, R. Y.; Ernst, W. G.

2007-01-01

248

X-ray microtomography at high pressure  

NASA Astrophysics Data System (ADS)

X-ray microtomography at high pressure is now possible with the rotating anvil apparatus (RAA) on the 13-BM- D beamline at the Advanced Photon Source (Argonne National Lab). The high-pressure X-ray tomography microscope (HPXTM) can be used to determine densities of amorphous materials (glasses and melts) and in situ characterization of 3D microstructure of multiphase materials subject to temperature and shear deformation [1, 2]. Densities may be obtained directly by volume rendering or from X-ray absorption. The rotating anvil apparatus is compressed by a 250-ton hydraulic press between concentric thrust bearings. Toroidal and truncated cylindrical (Drickamer) anvils can be accommodated. The latter anvils perform well up to 11.5 GPa and 1873K, using boron epoxy/diamond epoxy gaskets and X-ray transparent aluminum or polytherimide plastic containment rings. Differential rotation allows for controlled sample deformation. Pressure is determined by energy dispersive diffraction of an internal standard by convenient switching from monochromatic and polychromatic radiation. In-situ calibrations of linear attenuation coefficient permit bracketing of natural basalt density to better than 1 percent relative, while [2] used volume rendering to determine the compressibility of magnesium silicate glasses and supercooled liquid. The utility of the RRA to characterize microstructural evolution will be discussed. [1] Wang et al., Rev. Sci. Instrum., 76, 073709, 2005. [2] Lesher et al., PEPI, in press, DOI: 10.1016/j.pepi.2008.10.023, 2009

Lesher, C. E.; Wang, Y.; Gaudio, S.; Clark, A.; Yamada, A.; Sanehira, T.; Rivers, M.

2009-05-01

249

High temperature and pressure electrochemical test station  

NASA Astrophysics Data System (ADS)

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

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

2013-05-01

250

Dissociation of methane under high pressure.  

PubMed

Methane is an extremely important energy source with a great abundance in nature and plays a significant role in planetary physics, being one of the major constituents of giant planets Uranus and Neptune. The stable crystal forms of methane under extreme conditions are of great fundamental interest. Using the ab initio evolutionary algorithm for crystal structure prediction, we found three novel insulating molecular structures with P2(1)2(1)2(1), Pnma, and Cmcm space groups. Remarkably, under high pressure, methane becomes unstable and dissociates into ethane (C(2)H(6)) at 95 GPa, butane (C(4)H(10)) at 158 GPa, and further, carbon (diamond) and hydrogen above 287 GPa at zero temperature. We have computed the pressure-temperature phase diagram, which sheds light into the seemingly conflicting observations of the unusually low formation pressure of diamond at high temperature and the failure of experimental observation of dissociation at room temperature. Our results support the idea of diamond formation in the interiors of giant planets such as Neptune. PMID:20950018

Gao, Guoying; Oganov, Artem R; Ma, Yanming; Wang, Hui; Li, Peifang; Li, Yinwei; Iitaka, Toshiaki; Zou, Guangtian

2010-10-14

251

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

Code of Federal Regulations, 2010 CFR

...Draining of cargo hose: Categories A, B, C, and D. 153.1104 Section 153.1104...and Handling of Categories A, B, C, and D Cargo and Nls Residue § 153.1104...Draining of cargo hose: Categories A, B, C, and D. Before a cargo hose used...

2010-10-01

252

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

Code of Federal Regulations, 2010 CFR

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

2010-10-01

253

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

Code of Federal Regulations, 2010 CFR

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

2010-10-01

254

46 CFR 28.820 - Fire pumps, fire mains, fire hydrants, and fire hoses.  

Code of Federal Regulations, 2014 CFR

... false Fire pumps, fire mains, fire hydrants, and fire hoses...28.820 Fire pumps, fire mains, fire hydrants, and fire hoses...delivering an effective stream of water from a hose connected to...capable of producing a stream of water having a throw of at...

2014-10-01

255

46 CFR 28.820 - Fire pumps, fire mains, fire hydrants, and fire hoses.  

Code of Federal Regulations, 2012 CFR

... false Fire pumps, fire mains, fire hydrants, and fire hoses...28.820 Fire pumps, fire mains, fire hydrants, and fire hoses...delivering an effective stream of water from a hose connected to...capable of producing a stream of water having a throw of at...

2012-10-01

256

46 CFR 28.820 - Fire pumps, fire mains, fire hydrants, and fire hoses.  

Code of Federal Regulations, 2013 CFR

... false Fire pumps, fire mains, fire hydrants, and fire hoses...28.820 Fire pumps, fire mains, fire hydrants, and fire hoses...delivering an effective stream of water from a hose connected to...capable of producing a stream of water having a throw of at...

2013-10-01

257

CDC Vital Signs: High Blood Pressure and Cholesterol  

MedlinePLUS

... CDC.gov . Vital Signs Share Compartir High Blood Pressure and Cholesterol Out of Control February 2011 39 ... http://apps.nccd.cdc.gov/GISCVH2/ High Blood Pressure and High Cholesterol Among US Adults SOURCES: National ...

258

High Blood Pressure: Using an Ambulatory Blood Pressure Monitor  

MedlinePLUS

... can be worn under your clothes without anyone seeing it. The picture to the right shows a person wearing an ambulatory blood pressure monitor. This machine records and lets your doctor find out what ...

259

High pressure response of a high-purity iron  

Microsoft Academic Search

A series of time-resolved experiments has been done using a 50-mm-diameter light gas gun to characterize the shock uniaxial strain and high-strain-rate response of a high purity iron. The high-strain-rate uniaxial stress response of the iron was characterized using a Split-Hopkinson Pressure Bar. Shock wave experiments were done both with and without windows with a VISAR diagnostic to obtain time-resolved

L. R. Veeser; G. T. Gray; J. E. Vorthman; P. J. Rodriguez; R. S. Hixson; D. B. Hayes

2000-01-01

260

High Pressure Response of a High Purity Iron  

Microsoft Academic Search

A series of time-resolved experiments has been done using a 50-mm-diameter light gas gun to characterize the shock uniaxial strain and high-strain-rate response of a high purity iron. The high-strain-rate uniaxial stress response of the iron was characterized using a Split-Hopkinson Pressure Bar. Shock wave experiments were done both with and without windows with a VISAR diagnostic to obtain time-resolved

L. R. Veeser; G. T. Gray III; J. E. Vorthman; P. J. Rodriguez; R. S. Hixson

1999-01-01

261

Volatile solubility in magmas at high pressure  

NASA Astrophysics Data System (ADS)

We present a new theoretical approach for the solubility of volatiles in liquid silicates, with special emphasis on the effect of pressure, aiming at better understanding vesiculation processes in ascending magmas. We use the so-called "hard sphere fluid", a reference model widely used in liquid state physics for several decades. This simple model allows describing accurately, up to pressures of several hundreds of kilobars, the equation of state of pure gases. The model also applies very well to liquid silicates under pressure, by comparison to the scarce available experimental data. We use data on the density of melts at 1 bar to constrain the cohesion of such fluids. The hard sphere model also allows studying how a noble gas atom or a CO2 molecule dissolves into a silicate melt, a process governed by the equality of the solute chemical potentials in the melt and gas phase at equilibrium at T and P. The chemical potential consists of an entropic and an energetic contribution. The model enables one to evaluate readily the entropy of cavity formation to accommodate the solute particle through the density fluctuations of the solvent melt. Correlatively, a term describing the solvation energy is added to account for the interaction between the solute and the silicate network. The latter energetic term is directly constrained by the solubilites measured at 1 bar. The hard sphere model shows that compression is important for melt, but even stronger for fluid (for P typically > 10 kbar). We thus show, for the first time, that, when pressure increases, compression of melt is counterbalanced, up to several tens of kbar, by compression of fluid. This explains very well why experiments have seen an almost linear increase of volatile concentration in melt with increasing pressure. At P > 100 kbar, compression of the melt finally dominates and the solubility in melt eventually decreases. Therefore, volatile dissolution in silicate melt at high pressure certainly does not follow Henry's law (where gas is assumed ideal). We use our model to investigate vesiculation of tholeiites at mid-ocean ridges. The until now poorly understood He/Ar elemental fractionation recorded in Mid-Ocean Ridge Basalts is well explained if a melt (with about 0.8% CO2) starts to vesiculate at about 10 kbar (35 km below sea level), and suffers, during ascent, two or three vesiculation stages followed by vesicle loss and a last vesiculation with no loss. If these successive vesiculation events occur at various depths, this explains the large variability of the He/Ar ratios observed in MORBs.

Sarda, P.; Guillot, B.

2005-12-01

262

High-pressure promoted combustion chamber  

NASA Technical Reports Server (NTRS)

In the preferred embodiment of the promoted combusiton chamber disclosed herein, a thick-walled tubular body that is capable of withstanding extreme pressures is arranged with removable upper and lower end closures to provide access to the chamber for dependently supporting a test sample of a material being evaluated in the chamber. To facilitate the real-time analysis of a test sample, several pressure-tight viewing ports capable of withstanding the simulated environmental conditions are arranged in the walls of the tubular body for observing the test sample during the course of the test. A replaceable heat-resistant tubular member and replaceable flame-resistant internal liners are arranged to be fitted inside of the chamber for protecting the interior wall surfaces of the combustion chamber during the evaluation tests. Inlet and outlet ports are provided for admitting high-pressure gases into the chamber as needed for performing dynamic analyses of the test sample during the course of an evaluation test.

Rucker, Michelle A. (inventor); Stoltzfus, Joel M. (inventor)

1991-01-01

263

Treating High Blood Pressure in People with Diabetes  

MedlinePLUS

Treating High Blood Pressure in People with Diabetes American Diabetes Association? ? 1–800–DIABETES (342–2383)? ? www.diabetes.org ©2009 by ... having your blood pressure checked regularly. What is high blood pressure? Blood pressure is the force of blood flow ...

264

High Pressure Research Vol. 28, No. 3, September 2008, 273292  

E-print Network

High Pressure Research Vol. 28, No. 3, September 2008, 273­292 The COMPRES/GSECARS gas have designed and constructed a new system for loading gases at high pressure into diamond anvil cells at pressures up to 200 MPa. The gases are used either as quasi-hydrostatic pressure media surrounding

Jacobsen, Steven D.

265

High pressure-High temperature phases of Carbon Dioxide  

NASA Astrophysics Data System (ADS)

The phase diagram of CO2 has not been understood adequately above 40 GPa and high temperatures, particularly regarding the stabilities and boundaries of various extended phases that include a-carbonia, Phase V, Phase VI, and to an extent Phase III. We have studied the phase diagram of CO2 above 40 GPa and at high temperatures, using both ohmically and laser-heated diamond anvil cells. We found the co-existence of several extended phases over a large pressure region, which we attribute to the metastability of the extended phases and the extraordinarily large pressure gradients at these pressures. We determined the relative stability fields of the co-existing phases, which may offer the physico-chemical mechanism for the existence of carbonate minerals in deep Earth's mantle.

Sengupta, Amartya; Yoo, Choong-Shik

2009-03-01

266

HIGH PRESSURE COAL COMBUSTION KINETICS PROJECT  

SciTech Connect

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.

2003-01-28

267

High pressure proton disorder in brucite  

NASA Astrophysics Data System (ADS)

Brucite [Mg(OH)2] is one of the simplest hydrous phases and serves as a model system for complex hydrogen bearing silicates of Earth's mantle. Brucite belongs to a class of M(OH)2 compounds that appear to show unusual behavior at high pressure: the protons disorder while the MO sub-lattice remains crystalline. The nature and extent of proton disorder is uncertain. One can envision two types of proton disorder: 1) dynamic; the hydroxyl bond is tilted away from the c-axis and the proton hops between three symmetrically related potential wells or 2) static; each proton occupies a single well, and long-range order is frustrated by the hexagonal symmetry of the lattice. We explore the structure and physical properties of brucite over a wide range of pressure with density functional theory using the variable cell shape plane wave pseudopotential method in the local density (LDA) and generalized gradient (GGA) approximations. In this present study, we probe the energetics underlying the structure and dynamics of the proton sub-lattice by performing a series of constrained and unconstrained static calculations based on an energetically stable supercell wherein protons occupy 6i Wyckoff positions as opposed to 2d positions. We find that the equation of state and variation of lattice parameters of the superstructure with compression agree well with experiment. The displacement of the hydrogen from the three-fold axis (2d position) increases smoothly with increasing pressure. This means that even in the absence of dynamic disorder (i.e. at 0 K), the protons are frustrated and would be expected to exhibit long range disorder akin to a spin glass. In order to shed light on the dynamic nature of the proton hopping between the three energetically equivalent 6i sites, we have determined the activation barrier for such jumps. We find that the energy barrier increases with compression, possibly indicating a transition from dynamic proton disorder at lower pressures to static disorder at higher pressure. We have also investigated the possibility of proton jumps across the interlayer, by determining the potential energy well along the O?s\\)O vector. We infer that proton jumps across the interlayer are either strongly limited, or highly cooperative since we do not find any evidence of a double well along the O?s\\)O vector. This picture supports the view that brucite does not exhibit hydrogen bonding.

Mookherjee, M.; Stixrude, L.

2004-12-01

268

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

EPA Science Inventory

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

269

Parallel proton fire hose instability in gyrotropic Hall MHD model  

Microsoft Academic Search

The linear theory and nonlinear evolution of parallel or classical fire hose instability previously studied based on hybrid particle simulations are examined within the framework of a gyrotropic Hall magnetohydrodynamic (MHD) model that incorporates the ion inertial effects arising from the Hall current but neglects the electron inertia in the generalized Ohm's law. Both the ion cyclotron and whistler waves

B.-J. Wang; L.-N. Hau

2010-01-01

270

166. ARAIII Fire hose houses (Probably numbered on site as ...  

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

166. ARA-III Fire hose houses (Probably numbered on site as ARA-624). Aerojet-general 880-area/GCRE-701-S-4. Date: February 1958. Ineel index code no. 063-0624-00-013-102695. - Idaho National Engineering Laboratory, Army Reactors Experimental Area, Scoville, Butte County, ID

271

Mathematical modeling of spatial vibrations of lengthy hose structures  

Microsoft Academic Search

Spatial vibrations of hose constructions are considered with points of fastening under non-stationary kinematic actions. A model of hard rigid string is accepted as a computational model. The finite-difference method for the solution of equations of motion was used. A computational algorithm and a FORTRAN program were developed. The algorithm takes into account physical, geometrical and exploitative peculiarities of the

B. M. Perlov; M. B. Alesov

1996-01-01

272

NUCLEAR RESONANT SCATTERING AT HIGH PRESSURE AND HIGH TEMPERATURE  

Microsoft Academic Search

We introduce the combination of nuclear resonant inelastic X-ray scattering and synchrotron Mossbauer spectroscopy with the laser-heated diamond anvil cell technique for studying magnetic, elastic, thermodynamic, and vibrational properties of materials under high pressures and high temperatures. An Nd:YLF laser, operating in continuous donut mode (TEM01), has been used to heat samples inside a diamond anvil cell from both sides.

ERCAN E. ALPa

273

High pressure Hugoniot measurements using Mach waves  

NASA Astrophysics Data System (ADS)

In an effort to dramatically increase the range of pressures which can be accessed by traditional shock loading methods, a composite target assembly is examined. The target consists of two concentric cylinders aligned with the axial direction parallel to the loading, and is designed such that the outer cylinder will initially have a higher shock velocity than the inner material of interest. Conically converging shocks will be generated at the interface between the two materials due to the impedance mismatch. Upon convergence, an irregular reflection occurs and the conical analog of a Mach reflection develops. The Mach reflection will grow until it reaches a steady state, at which point the wave configuration becomes self similar. The resulting high pressure Hugoniot state can then be measured using velocity interferometry and impedance matching. The technique is demonstrated using a planar mechanical impact generated by a powder gun to study the shock response of copper. Two systems are examined which utilize either a low impedance (6061-T6 aluminum) or a high impedance (molybdenum) outer cylinder. A dual-delay multipoint VISAR experiment will be presented to validate the technique, and will be compared to both numerical simulations and a simple hydrodynamic model. The feasibility of measuring an entire Hugoniot curve using full field velocity interferometry (ORVIS) will also be discussed, and initial experiments will be presented.

Brown, Justin; Ravichandran, Guruswami

2011-06-01

274

High pressure-resistant nonincendive emulsion explosive  

DOEpatents

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

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

1994-01-01

275

Pressure Distribution Over Airfoils at High Speeds  

NASA Technical Reports Server (NTRS)

This report deals with the pressure distribution over airfoils at high speeds, and describes an extension of an investigation of the aerodynamic characteristics of certain airfoils which was presented in NACA Technical Report no. 207. The results presented in report no. 207 have been confirmed and extended to higher speeds through a more extensive and systematic series of tests. Observations were also made of the air flow near the surface of the airfoils, and the large changes in lift coefficients were shown to be associated with a sudden breaking away of the flow from the upper surface. The tests were made on models of 1-inch chord and comparison with the earlier measurements on models of 3-inch chord shows that the sudden change in the lift coefficient is due to compressibility and not to a change in the Reynolds number. The Reynolds number still has a large effect, however, on the drag coefficient. The pressure distribution observations furnish the propeller designer with data on the load distribution at high speeds, and also give a better picture of the air-flow changes.

Briggs, L J; Dryden, H L

1927-01-01

276

High blood pressure - what to ask your doctor  

MedlinePLUS

What to ask your doctor about high blood pressure; Hypertension - what to ask your doctor ... problems? What medicines am I taking to treat high blood pressure? Do they have any side effects? What should ...

277

High Blood Pressure, Afib and Your Risk of Stroke  

MedlinePLUS

... have a stroke for the first time have high blood pressure . And an irregular atrial heart rhythm — a condition ... 800,000 Americans suffer a stroke each year. High blood pressure is the chief culprit, and atrial fibrillation isn’ ...

278

A Nutritional Strategy for the Treatment of High Blood Pressure.  

ERIC Educational Resources Information Center

Some physicians wonder if high blood pressure can be controlled without the use of drugs and their potential side effects. Current findings concerning nutrition and high blood pressure are presented. (RM)

Podell, Richard N.

1984-01-01

279

High Blood Pressure Treatment in Children (Beyond the Basics)  

MedlinePLUS

... less than two hours per day. Participation in sports — Children who have controlled high blood pressure are generally allowed to participate in competitive sports. Children and adolescents with high blood pressure are ...

280

Talk with Your Health Care Provider about High Blood Pressure  

MedlinePLUS

... With Your Health Care Provider About High Blood Pressure Partnership for HEALTH Here are some questions to ... you do to prevent or control high blood pressure? 1. Quit smoking and/or chewing tobacco. Ask ...

281

High-pressure coal fuel processor development  

SciTech Connect

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))

1992-12-01

282

High pressure Hugoniot measurements using converging shocks  

NASA Astrophysics Data System (ADS)

Plate impact experiments are a powerful tool in equation of state development, but are inherently limited by the range of impact velocities accessible to the facility. In an effort to dramatically increase the range of pressures which can be studied with available impact velocities, a new experimental technique is examined. The target plate is replaced by a composite assembly consisting of two concentric cylinders. The target is designed such that the initial shock velocity in a well-characterized outer cylinder is higher than in the inner cylinder material of interest. Conically converging shocks will be generated at the interface due to the impedance mismatch between the two materials and axisymmetric geometry. Upon convergence, an irregular reflection occurs and the conical analog of a Mach reflection develops. This Mach reflection grows until it reaches a steady state, at which point the high pressure state in the Mach disk can be measured using velocity interferometry and impedance matching techniques. The technique is demonstrated by studying the shock response of copper. A strong confinement setup utilizes a low impedance 6061-T6 aluminum outer cylinder and the weak confinement case features a higher impedance molybdenum outer cylinder. The experimental results for copper are in good agreement with a simple analytical model, numerical simulations, and data in the literature. The possibility of utilizing full field measurements to make multiple Hugoniot measurements is also examined.

Brown, J. L.; Ravichandran, G.; Reinhart, W. D.; Trott, W. M.

2011-05-01

283

Investigating cavity pressure behavior in high-pressure RTM process variants  

NASA Astrophysics Data System (ADS)

The paper addresses new variants of the high pressure resin transfer molding (HP-RTM) process namely high pressure injection RTM (HP-IRTM) and high pressure compression RTM (HP-CRTM) for manufacturing of carbon fiber reinforced composites with high fiber volume content. Both these processes utilize high-pressure RTM equipment for precise dosing and mixing of highly reactive epoxy resin and amine hardener with relatively high throughput rates. The paper addresses results of a study which investigated cavity pressure measurement for both the HP-RTM process variants using a specially designed highpressure RTM mold. The investigations indicate that the cavity pressure built up is a characteristic of the selected process variant. Further the relationship between the applied press force and the cavity pressure in HP-CRTM process was studied.

Rosenberg, P.; Chaudhari, R.; Karcher, M.; Henning, F.; Elsner, P.

2014-05-01

284

Effect of high pressure on structural oddities   

E-print Network

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

Johnstone, Russell D. L.

2010-01-01

285

High Pressure Quick Disconnect Particle Impact Tests  

NASA Technical Reports Server (NTRS)

NASA Johnson Space Center White Sands Test Facility (WSTF) performed particle impact testing to determine whether there is a particle impact ignition hazard in the quick disconnects (QDs) in the Environmental Control and Life Support System (ECLSS) on the International Space Station (ISS). Testing included standard supersonic and subsonic particle impact tests on 15-5 PH stainless steel, as well as tests performed on a QD simulator. This paper summarizes the particle impact tests completed at WSTF. Although there was an ignition in Test Series 4, it was determined the ignition was caused by the presence of a machining imperfection. The sum of all the test results indicates that there is no particle impact ignition hazard in the ISS ECLSS QDs. KEYWORDS: quick disconnect, high pressure, particle impact testing, stainless steel

Rosales, Keisa R.; Stoltzfus, Joel M.

2009-01-01

286

Ceramic high pressure gas path seal  

NASA Technical Reports Server (NTRS)

Stage 1 ceramic shrouds (high pressure turbine gas path seal) were developed for the GE T700 turbine helicopter engine under the Army/NASA Contract NAS3-23174. This contract successfully proved the viability and benefits of a Stage 1 ceramic shroud for production application. Stage 1 ceramic shrouds were proven by extensive component and engine testing. This Stage 1 ceramic shroud, plasma sprayed ceramic (ZrOs-BY2O3) and bond coating (NiCrAlY) onto a cast metal backing, offers significant engine performance improvement. Due to the ceramic coating, the amount of cooling air required is reduced 20% resulting in a 0.5% increase in horsepower and a 0.3% decrease in specific fuel consumption. This is accomplished with a component which is lower in cost than the current production shroud. Stage 1 ceramic shrouds will be introduced into field service in late 1987.

Liotta, G. C.

1987-01-01

287

Safety improvements in high pressure thermal machines  

SciTech Connect

In a thermal machine of the type including a machine body having a main axis extending between a thermal end and a work end, a working fluid at relatively high pressure in a working fluid chamber defined in the body and a displacer element reciprocable within the chamber for subjecting the fluid to a thermodynamic cycle in cooperation with a reciprocable work piston, the improvement is described comprising outer shell means enclosing the machine body for maintaining a substantially sealed atmosphere about the machine body, and diffuser means arranged between the machine body and the outer shell means for diffusing a shock wave traveling towards the outer shell means resulting from explosive failure of the machine body and for shielding the outer shell means against fragments projected upon such failure.

Otters, J.L.

1988-02-09

288

Condensed matter at high shock pressures  

SciTech Connect

Experimental techniques are described for shock waves in liquids: Hugoniot equation-of-state, shock temperature and emission spectroscopy, electrical conductivity, and Raman spectroscopy. Experimental data are reviewed and presented in terms of phenomena that occur at high densities and temperatures in shocked He, Ar, N/sub 2/, CO, SiO/sub 2/-aerogel, H/sub 2/O, and C/sub 6/H/sub 6/. The superconducting properties of Nb metal shocked to 100 GPa (1 Mbar) and recovered intact are discussed in terms of prospects for synthesizing novel, metastable materials. Ultrahigh pressure data for Cu is reviewed in the range 0.3 to 6TPa (3 to 60 Mbar). 56 refs., 9 figs., 1 tab.

Nellis, W.J.; Holmes, N.C.; Mitchell, A.C.; Radousky, H.B.; Hamilton, D.

1985-07-12

289

High pressure hugoniot measurements using mach waves  

NASA Astrophysics Data System (ADS)

Traditionally, most dynamic shock compression experiments are conducted using a plane one-dimensional wave of uniaxial strain. In this case, the evaluation of the equation of state is simplified due to the geometry, but the amplitude of the induced shock wave is limited by the magnitude of the input load. In an effort to dramatically increase the range of pressures that can be accessed by traditional loading methods, a composite target assembly is examined. The target consists of two concentric cylinders aligned with the axial direction parallel to the loading. The target is designed such that on initial loading, the outer cylinder will have a higher shock velocity than the inner material of interest. Conically converging shocks will be generated at the interface between the two materials due to the impedance mismatch. Upon convergence, an irregular reflection occurs and the conical analog of a Mach reflection develops. The Mach reflection will grow until it reaches a steady state, at which point the wave configuration becomes self similar. The resulting high pressure Hugoniot state can then be measured using velocity interferometry and impedance matching. The technique is demonstrated using a planar mechanical impact generated by a powder gun to study the shock response of copper. Two systems are examined which utilize either a low impedance (6061-T6 aluminum) or a high impedance (molybdenum) outer cylinder. A multipoint VISAR experiment will be presented to validate the technique, and will be compared to numerical simulations. The feasibility of measuring an entire Hugoniot curve using full field velocity interferometry (ORVIS) will also be discussed.

Brown, Justin; Ravichandran, Guruswami

2012-03-01

290

Catalytic propertiess of proteinases under high pressure  

Microsoft Academic Search

Effect of much higher pressure on thermolysin was investigated with regard to the proteinase activity on protein substrates, the intrinsic Trp fluorescence during and after the pressure incubation, limited proteolysis by subtilisin, autolysis, and residual activity after prolonged incubations. Though thermolysin is known to perform a remarkable pressure-induced activation at 100 or 150 MPa, it was revealed to be not

S. Kunugi; Y. Kanazawa; K. Mano; A. Koyasu; T. Inagaki

1996-01-01

291

High-pressure melting curve of hydrogen  

Microsoft Academic Search

The melting curve of hydrogen was computed for pressures up to 200 GPa, using molecular dynamics. The inter- and intramolecular interactions were described by the reactive force field (ReaxFF) model. The model describes the pressure-volume equation of state solid hydrogen in good agreement with experiment up to pressures over 150 GPa, however the corresponding equation of state for liquid deviates

Sergio M. Davis; Anatoly B. Belonoshko; Börje Johansson; Natalia V. Skorodumova; Adri C. T. van Duin

2008-01-01

292

Calculating Mass Diffusion in High-Pressure Binary Fluids  

NASA Technical Reports Server (NTRS)

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

Bellan, Josette; Harstad, Kenneth

2004-01-01

293

Negative pressure effects in high-pressure oxygen-intercalated C{sub 60}  

SciTech Connect

We have observed unexpected and as yet unexplained negative pressure effects in high-oxygen-pressure-treated C{sub 60} in which the orientational ordering temperature is greatly depressed. Such effects are not observed in identical studies with nitrogen.

Schirber, J.E.; Assink, R.A.; Samara, G.A.; Morosin, B.; Loy, D. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)] [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

1995-06-01

294

High pressure, high temperature studies of methane-water mixtures  

Microsoft Academic Search

Recently, experiments conducted on methane at high pressures and temperatures have produced evidence to suggest that abiogenic processes in the upper mantle have the potential to yield longer-chain hydrocarbons, including petroleum spectrum hydrocarbons. We have conducted in-situ Raman scattering measurements in the laser-heated diamond-anvil cell on methane-water mixtures to characterize how an oxidizing agent, water, would alter methane-methane interactions from

T. J. Hittinger; A. F. Goncharov; D. A. Dalton; R. S. McWilliams; M. Mahmood

2010-01-01

295

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

E-print Network

THREE PRECISION DIFFERENTIAL PRESSURE INDICATORS FOR OPERATION AT HIGH TEMPERATURES AND PRESSURES A Thesis by DOUGLAS CLAYTON OSBURN III Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement... for the degree of MASTER OF SCIENCE May 1981 Major Subject: Chemical Engineering THREE PRECISION DIFFERENTIAL PRESSURE INDICATORS FOR OPERATION AT HIGH TEMPERATURES AND PRESSURES A Thesis by DOUGLAS CLAYTON OSBURN III Approved as to style and content by...

Osburn, Douglas Clayton

2012-06-07

296

High Pressure Research Vol. 29, No. 2, June 2009, 235244  

E-print Network

and (or) pressure conditions, the marcasite-type compounds have a number of different polymorphs. Pyrite], and a high-pressure pyrite-type phase of NiP2 has been synthesized [7]. At high temperature and pressure, Cr atoms and two Cr atoms [8,9]. Goodenough [10] has described energy bands of MX2 compounds with pyrite

Steinle-Neumann, Gerd

297

Do Pregnant Women Need High Blood Pressure Treatment?  

MedlinePLUS

... enable JavaScript. Do Pregnant Women Need High Blood Pressure Treatment? Controlling blood pressure doesn't seem to affect baby, but may ... January 28, 2015 Related MedlinePlus Page High Blood Pressure in Pregnancy WEDNESDAY, Jan. 28, 2015 (HealthDay News) -- ...

298

Structural behaviour of niobium oxynitride under high pressure  

SciTech Connect

High pressure investigation of niobium oxynitrides (NbN{sub 0.98}O{sub 0.02}) employing synchrotron based angle dispersive x-ray diffraction experiments was carried out in very fine pressure steps using membrane driven diamond anvil cell. Ambient cubic phase was found to be stable up to ?18 GPa. At further high pressure cubic phase showed rhombohedral distortion.

Sharma, Bharat Bhooshan, E-mail: bbs86phy@gmail.com; Poswal, H. K., E-mail: bbs86phy@gmail.com; Pandey, K. K., E-mail: bbs86phy@gmail.com; Sharma, Surinder M., E-mail: bbs86phy@gmail.com [High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Center, Mumbai-400085 (India); Yakhmi, J. V. [Homi Bhabha National Institute, Mumbai - 400094 (India); Ohashi, Y.; Kikkawa, S. [Faculty of Engineering, Hokkaido University, N13W8, Sapporo 080-8628 (Japan)

2014-04-24

299

High Pressure Rotary Shaft Sealing Mechanism  

DOEpatents

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

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

2001-05-08

300

Automated high pressure cell for pressure jump x-ray diffraction  

SciTech Connect

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

Brooks, Nicholas J.; Gauthe, Beatrice L. L. E.; Templer, Richard H.; Ces, Oscar; Seddon, John M. [Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Terrill, Nick J. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Rogers, Sarah E. [ISIS, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom)

2010-06-15

301

High pressure high temperature elasticity study of sodium disilicate glass  

NASA Astrophysics Data System (ADS)

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

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

2011-12-01

302

9. General view of engine between cylinders with high pressure ...  

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

9. General view of engine between cylinders with high pressure cylinder on left and low pressure cylinder on right. - Carnegie Steel-Ohio Works, Steam Engines, 912 Salt Springs Road, Youngstown, Mahoning County, OH

303

High Temperature High Pressure Thermodynamic Measurements for Coal Model Compounds  

SciTech Connect

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

John C. Chen; Vinayak N. Kabadi

1998-11-12

304

Emissionless double containment hose for critical service applications  

SciTech Connect

The overwhelming need for reliable hoses for critical applications has led to the development of a double containment hose. Two barriers of polytetrafluoroethylene (PTFE) protect the environment, personnel and equipment from the hazardous chemicals being conveyed. PTFE tubing is reinforced with two layers of Alloy C276 (N10276) wire braid, which terminate with Alloy 400 (N04400) or Alloy C276 end connections. Advantages of the design include containment in the event of a leak in the primary tubing, monitorability of the interstitial space, extended service life, corrosion resistance, superior burst strength, vacuum resistance, kink resistance and product purity. Monitorability is achieved through a vent port containing a unique Alloy C276 porous disc.

Harris, B.S. [Crane Resistoflex, Marion, NC (United States)

1999-11-01

305

Dynamical stability analysis of a hose to the sky  

NASA Astrophysics Data System (ADS)

The Stratospheric Shield was proposed as a geoengineering concept to control the Earth's climate and reverse global warming. This approach seeks to release sulphur dioxide (SO2) aerosols in the stratosphere to decrease the amount of sunlight that reaches the surface of the Earth. It was proposed that this can be done by pumping liquefied SO2 from the ground to the stratosphere in a 30 km long hose supported by aerostats.

Gosselin, Frédérick P.; Païdoussis, Michael P.

2014-01-01

306

Liquid Rocket Lines, Bellows, Flexible Hoses, and Filters  

NASA Technical Reports Server (NTRS)

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

1977-01-01

307

Development of high pressure gas cells at ISIS  

NASA Astrophysics Data System (ADS)

High-pressure research is one of the fastest-growing areas of natural science, and one that attracts as diverse communities as those of physics, bio-physics, chemistry, materials science and earth science. In condensed matter physics there are a number of highly topical areas, such as quantum criticality, pressure-induced superconductivity or non-Fermi liquid behaviour, where pressure is a fundamental parameter. Reliable, safe and user-friendly high pressure gas handling systems with gas pressures up to 1GPa should make a significant impact on the range of science possible. The ISIS facility is participating in the NMI3 FP7 sample environment project supported by the European Commission which includes high pressure gas cell development. In this paper the progress in designing, manufacturing and testing a new generation of high pressure gas cells for neutron scattering experiments is discussed.

Kirichek, O.; Done, R.; Goodway, C. M.; Kibble, M. G.; Evans, B.; Bowden, Z. A.

2012-02-01

308

Single stage high pressure centrifugal slurry pump  

DOEpatents

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

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

1984-03-27

309

High Blood Pressure and Kidney Disease  

MedlinePLUS

... and other blood pressure medications. Eating, Diet, and Nutrition Following a healthy eating plan can help lower blood pressure. A health care ... which often comes from salt. The DASH eating plan is low in fat and ... recommend this type of diet for people who have already developed kidney disease. ...

310

Hydrogen solubility in cristobalite at high pressure.  

PubMed

Powder samples of cristobalite-I are loaded with hydrogen at pressures up to 90 kbar and T = 250 °C and quenched under pressure to the liquid N2 temperature. The quenched samples are examined at ambient pressure by X-ray diffraction, Raman spectroscopy, and thermal desorption analysis. The hydrogen content of the samples is found to increase with pressure and reach a molecular ratio of H2/SiO2 ? 0.10 at P = 90 kbar. At ambient pressure, the samples consist of a mixture of approximately 80% cristobalite-I phase and 20% cristobalite-II-like phase, the crystal lattices of both phases being slightly expanded due to the hydrogen uptake. According to Raman spectroscopy, the hydrogen is dissolved in these phases in the form of H2 molecules. PMID:25322160

Efimchenko, Vadim S; Fedotov, Vladimir K; Kuzovnikov, Mikhail A; Meletov, Konstantin P; Bulychev, Boris M

2014-11-01

311

Evidence of Tetragonal Nanodomains in the high pressure polymorph  

SciTech Connect

The pressure induced P4mm {yields} Pm{bar 3}m phase transition in BaTiO{sub 3} perovskite was investigated by x-ray total scattering. The evolution of the structure was analyzed by fitting pair distribution functions over a pressure range from ambient pressure up to 6.85(7) GPa. Evidence for the existence of tetragonal ferroelectric nanodomains at high pressure was found. The average size of the nanodomains in the high-pressure phase decreases with increasing pressure. Extrapolation of the domain size to pressures higher than studied experimentally suggests a disappearance of the ferroelectric domains at about 9.3(5) GPa and a cubic symmetry of BaTiO{sub 3} high-pressure phase.

Ehm, L.; Borkowski, L.A.; Parise J.B.; Ghose, S.; Chen, Z.

2010-12-17

312

Compression heating of selected pressure transmitting fluids and liquid foods during high hydrostatic pressure treatment  

Microsoft Academic Search

Three pressure transmitting fluids (water, ethylene glycol, and ethanol) and three liquid foods (orange juice, whole, and skim milk) were pressurized at 100–400MPa and at 5, 20 and 35°C, using different compression rates (100, 200, and 300MPa\\/min) to evaluate the adiabatic heating phenomena during high hydrostatic pressure (HHP) processing. A pressure vessel (3L volume) in which liquid foods could be

Sencer Buzrul; Hami Alpas; Alain Largeteau; Faruk Bozoglu; Gérard Demazeau

2008-01-01

313

High Pressure Response of a High Purity Iron  

NASA Astrophysics Data System (ADS)

A series of time-resolved experiments has been done using a 50-mm-diameter light gas gun to characterize the shock uniaxial strain and high-strain-rate response of a high purity iron. The high-strain-rate uniaxial stress response of the iron was characterized using a Split-Hopkinson Pressure Bar. Shock wave experiments were done both with and without windows with a VISAR diagnostic to obtain time-resolved particle velocity data. The shock experiments with windows yield information on elastic/plastic response, transformation kinetics, sound speed, and quasi-elastic release. Experiments were conducted without windows both below and above the alpha-epsilon phase transformation to study the effect of phase kinetics and the release transition on the spallation response in iron. Results of the shock and Hopkinson bar experiments will be compared and contrasted to previous research on iron.

Veeser, L. R.; Gray, G. T., III; Vorthman, J. E.; Rodriguez, P. J.; Hixson, R. S.

1999-06-01

314

High pressure response of a high-purity iron  

NASA Astrophysics Data System (ADS)

A series of time-resolved experiments has been done using a 50-mm-diameter light gas gun to characterize the shock uniaxial strain and high-strain-rate response of a high purity iron. The high-strain-rate uniaxial stress response of the iron was characterized using a Split-Hopkinson Pressure Bar. Shock wave experiments were done both with and without windows with a VISAR diagnostic to obtain time-resolved particle velocity data. The shock experiments with windows yield information on elastic/plastic response, transformation kinetics, sound speed, and quasi-elastic release. Experiments were conducted without windows both below and above the ?-to-? phase transformation to study the effect of phase-change kinetics and the release transition on the spallation response in iron. Results of the shock and Hopkinson bar experiments are compared and contrasted to previous research on iron.

Veeser, L. R.; Gray, G. T.; Vorthman, J. E.; Rodriguez, P. J.; Hixson, R. S.; Hayes, D. B.

2000-04-01

315

Interactions of high hydrostatic pressure, pressurization temperature and pH on death and injury of pressure-resistant and pressure-sensitive strains of foodborne pathogens  

Microsoft Academic Search

The objective of this study is to determine the interactions between high hydrostatic pressure, pressurization temperature, time and pH during pressurization on death and injury of pressure-resistant and pressure-sensitive strains of four foodborne pathogens: Staphylococcus aureus 485 and 765, Listeria monocytogenes CA and OH2, Escherichia coli O157:H7 933 and 931, Salmonella enteritidis FDA and Salmonella typhimurium E21274. Among these strains

H Alpas; N Kalchayanand; F Bozoglu; B Ray

2000-01-01

316

System and method of delivering low\\/pressure\\/low temperature fluids into high pressure\\/high temperature heat exchangers by means of alternate pressure equalization  

Microsoft Academic Search

An improved system is described and method of introducing low pressure fluids into a high pressure heat exchanger wherein the method includes the following steps: delivering a fluid in the liquid state into a storage tank wherein atmospheric pressure equilibrium exists; delivering the liquid from the storage tank into alternating tanks, under alternating conditions; delivering atmospheric pressure equilibrium between the

1987-01-01

317

Preliminary results of MUNDO high altitude pressure measurements  

Microsoft Academic Search

Four high altitude pressure measurement canisters were deployed for the MUNDO event. All canister parachutes deployed and the placement of instruments was quite satisfactory in spite of an unusual wind change. Fouled leak plugs caused the two intermediate pressure transducers to be driven out of range but a new and reasonably successful procedure was developed for recovering the pressure histories

J. R. Banister; W. V. Hereford; O. M. Solomon

1987-01-01

318

AIR-BLAST PHENOMENA IN THE HIGH-PRESSURE REGION  

Microsoft Academic Search

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

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

1960-01-01

319

High Hydrostatic Pressure Processing of Fruit and Vegetable Products  

Microsoft Academic Search

High hydrostatic pressure (HHP) as a minimal thermal technology is a valuable tool for microbiologically safe and shelf-stable fruit and vegetable production. Microorganisms and deteriorative enzymes can be inhibited or inactivated depending on the amount of pressure and time applied to the product. The resistance of microorganisms and enzymes to pressure in fruit and vegetable products also is dependent on

José A. Guerrero-Beltrán; Gustavo V. Barbosa-Cánovas; Barry G. Swanson

2005-01-01

320

High pressure CVD inside microstructured optical fibres  

Microsoft Academic Search

We report the fabrication of semiconductor structures within holey fibres via a pressure driven microfluidic chemical vapour deposition process, demonstrating templated growth of crystalline Group IV semiconductor structures and devices in extreme aspect ratio geometries.

Pier J. A. Sazio; Adrian Amezcua-Correa; Chris E. Finlayson; John R. Hayes; Thomas J. Scheidemantel; Feng Zhang; Elena R. Margine; Neil F. Baril; Bryan R. Jackson; John V. Badding; Dong-Jin Won; Venkatraman Gopalan; Vincent H. Crespi

2006-01-01

321

Is exercise good for high blood pressure?  

PubMed Central

Ten men with uncomplicated essential hypertension (mean standing blood pressure 165/109 mm Hg) and 10 normal controls matched for age and weight were studied for the hypotensive potential of moderate exercise. Tests were conducted on a treadmill set to induce a steady heart rate of 120 beats/min and performed over five 10-minute periods separated by three minutes' rest and finishing with 30 minutes' sitting quietly in a chair. During exercise the mean systolic pressures were identical in the hypertensive patients and controls (175±SEM 5 mm Hg), the controls therefore sustaining an appreciably greater increase in pressure. During the 30-minute rest period after the tests both the control and hypertensive groups showed a significant and sustained fall in absolute systolic pressures as compared with pre-exercise values (p <0·001), the mean percentage reductions being 22% and 25% respectively. If a fall in blood pressure after exercise is maintained for four to 10 hours, then a “good walk” twice a day might be reasonable treatment for mild hypertension. Studies are continuing to determine the amount of exercise needed and the duration for which the reduction in blood pressure is maintained. PMID:6810991

Wilcox, R G; Bennett, T; Brown, A M; Macdonald, I A

1982-01-01

322

Development of compact high pressure COIL  

NASA Astrophysics Data System (ADS)

An advanced nozzle, also known as ejector nozzle, suitable for a 500 W class COIL employing an active medium flow of nearly 12 gm/s has been developed and used instead of conventional slit nozzle. The nozzle has been tested in both cold as well as hot run conditions of COIL achieving a typical cavity pressure of nearly 10 torr, pitot pressure of ~ 85 torr and a cavity Mach number of ~2.5. The present study details the gas dynamic aspects and detailed numerical studies of this ejector nozzle and highlights its potential as a COIL pressure recovery device. This nozzle in conjunction with a diffuser is capable of achieving pressure recovery of ~ 60 torr, equivalent to the much cumbersome first stage of the pressure recovery system used in case of conventional slit nozzle based system. . Thus use of this nozzle in place of conventional slit nozzle can achieve the atmospheric discharge using single stage ejector system thereby making the pressure recovery system quite compact.

Singhal, Gaurav; Rajesh, R.; Mainuddin; Tyagi, R. K.; Dawar, A. L.; Subbarao, P. M. V.; Endo, M.

2005-09-01

323

High-temperature, high-pressure optical cell  

NASA Technical Reports Server (NTRS)

The invention is an optical cell for containment of chemicals under conditions of high temperature and high pressure. The cell is formed of a vitreous silica tube, two optical windows comprising a vitreous silica rod inserted into the ends of a tube, and fused into position in the tube ends. Windows are spaced apart to form a cavity enclosed by the tube and the windows. A hole is drilled radially through the tube and into the cavity. Another vitreous silica tube is fused to the silica tube around the hole to form the stem, which is perpendicular to the long axis of the tube. The open end of the stem is used to load chemicals into the cavity. Then the stem may be sealed, and if desired, it may be shortened in order to reduce the volume of the cavity, which extends into the stem.

Harris, R. P. (inventor); Holland, L. R. (inventor); Smith, R. E. (inventor)

1986-01-01

324

High pressure/high temperature thermogravimetric apparatus. Final report  

SciTech Connect

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

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

1999-12-01

325

High-pressure Infrared Spectra of Tal and Lawsonite  

SciTech Connect

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.

2007-01-01

326

A description of electron heating with an electrostatic potential jump in a parallel, collisionless, fire hose shock  

NASA Technical Reports Server (NTRS)

The electron heating required if protons scatter elastically in a parallel, collisionless shock is calculated. Near-elastic proton scattering off large amplitude background magnetic field fluctuations might be expected if the waves responsible for the shock dissipation are generated by the fire hose instability. The effects of an electrostatic potential jump in the shock layer are included by assuming that the energy lost by protons in traversing the potential jump is converted into electron thermal pressure. It is found that the electron temperature increase is a strong function of the potential jump. Comparison is made to the parallel shock plasma simulation of Quest (1987).

Ellison, Donald C.; Jones, Frank C.

1988-01-01

327

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

NASA Astrophysics Data System (ADS)

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

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

2014-03-01

328

Elasticity and Structure of Chromite at High Pressure  

NASA Astrophysics Data System (ADS)

Chromite is commonly found in the Earth's crust and mantle. Recently, a high-pressure chromite polymorph was discovered in the shocked Suizhou meteorite. Therefore, it would be of great interest to investigate the high-pressure phase in chromite composition that can be inferred as a shock scale for the meteorite. In this study, natural and synthetic chromites were studied by Raman spectroscopy and x-ray diffraction in a diamond anvil cell. Our high-pressure results show that cubic magnesiochromite transforms to tetragonal I41/amd structure at pressures above 20 GPa. The volume data for magnesiochromite fit to Birch-Murnaghan equation of state (EOS) yield K0 = 189(2) GPa, K0' = 7.2(3) and V0 = 578.68(4) Å3, in agreement with theoretical calculations. The EOS of the high pressure tetragonal phase was obtained as K0 = 191(8) GPa and V0 = 279(1) Å3 when K0' = 4. The volume reduction at phase transition is about 4.4%. The high pressure phase is unquenchable and transformed back to magnesiochromite with little hysteresis upon release of pressure. Similarly, the natural chromite also exhibits a phase transition near 21 GPa at 300 K and then another high-pressure phase was found at 31 GPa and 1800-2000 K. However, this high pressure and high temperature phase cannot be retained at ambient conditions.

Shieh, S. R.; Yong, W.; MI, Z.; Botis, S. M.; Shi, W.; Withers, A. C.

2012-12-01

329

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

EPA Science Inventory

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

330

Evaluation of high-pressure drilling fluid supply systems  

SciTech Connect

A study was undertaken to help determine the technical and economic feasibility of developing a high-pressure fluid-jet drilling system for the production of geothermal wells. Three system concepts were developed and analyzed in terms of costs, component availability, and required new-component development. These concepts included a single-conduit system that supplies the downhole cutting nozzles directly via surface-located high-pressure pumps; a single-conduit system utilizing low-pressure surface pumps to supply and operate a high-pressure downhole pump, which in turn supplies the cutting nozzles; and a dual-conduit system supplying surface-generated high-pressure fluid for cutting via one conduit and low-pressure scavenging fluid via the other. It is concluded that the single-conduit downhole pump system concept has the greatest potential for success in this application. 28 figures, 11 tables.

McDonald, M.C.; Reichman, J.M.; Theimer, K.J.

1981-10-01

331

High-temperature fiber optic cubic-zirconia pressure sensor  

NASA Astrophysics Data System (ADS)

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

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

2005-12-01

332

Structural changes in thermoelectric SnSe at high pressures.  

PubMed

The crystal structure of the thermoelectric material tin selenide has been investigated with angle-dispersive synchrotron x-ray powder diffraction under hydrostatic pressure up to 27 GPa. With increasing pressure, a continuous evolution of the crystal structure from the GeS type to the higher-symmetry TlI type was observed, with a critical pressure of 10.5(3) GPa. The orthorhombic high-pressure modification, ?'-SnSe, is closely related to the pseudo-tetragonal high-temperature modification at ambient pressure. The similarity between the changes of the crystal structure at elevated temperatures and at high pressures suggests the possibility that strained thin films of SnSe may provide a route to overcoming the problem of the limited thermal stability of ?-SnSe at high temperatures. PMID:25629387

Loa, I; Husband, R J; Downie, R A; Popuri, S R; Bos, J-W G

2015-02-25

333

Transient High-Pressure Fuel Injection  

NASA Astrophysics Data System (ADS)

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

Jarrahbashi, Dorrin

334

High pressure phase transitions in tetrahedrally coordinated semiconducting compounds  

NASA Technical Reports Server (NTRS)

New experimental results are reported for structural transitions at high pressure in several III-V compounds and two II-VI compounds. These data, together with earlier results, are then compared with the predictions of model calculations of Van Vechten. Experimental transition pressures are often at variance with calculated values. However, his calculation assumes that the high pressure phase is metallic, with the beta-Sn structure. The present results show that several compounds assume an ionic NaCl structure at high pressure, while others have neither the beta-Sn nor NaCl structure.

Yu, S. C.; Spain, I. L.; Skelton, E. F.

1978-01-01

335

High-pressure phase transition in LiBH 4  

NASA Astrophysics Data System (ADS)

The high-pressure phase transition from ambient pressure ?-LiBH 4 to high-pressure ?-LiBH 4 was observed by Raman spectroscopy and X-ray diffraction between 0.8 and 1.1 GPa. The phase boundary between these two phases was mapped over a large range of temperatures using thermal conductivity studies and differential thermal analysis. The structure of the high-pressure phase could not be identified due to small number of experimentally observed reflections, but it was shown that it is different from previously reported theoretical predictions.

Talyzin, A. V.; Andersson, O.; Sundqvist, B.; Kurnosov, A.; Dubrovinsky, L.

2007-02-01

336

Foil-like manganin gauges for dynamic high pressure measurements  

NASA Astrophysics Data System (ADS)

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

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

2011-07-01

337

Recent progress in high pressure metrology in Europe  

NASA Astrophysics Data System (ADS)

Five European national metrology institutes in collaboration with a university, a research institute and five industrial companies are working on a joint research project within a framework of the European Metrology Research Programme aimed at development of 1.6 GPa primary and 1.5 GPa transfer pressure standards. Two primary pressure standards were realised as pressure-measuring multipliers, each consisting of a low pressure and a high pressure (HP) piston-cylinder assembly (PCA). A special design of the HP PCAs was developed in which a tungsten carbide cylinder is supported by two thermally shrunk steel sleeves and, additionally, by jacket pressure applied to the outside of the outer sleeve. Stress-strain finite element analysis (FEA) was performed to predict behaviour of the multipliers and a pressure generation system. With FEA, the pressure distortion coefficient was determined, taking into account irregularities of the piston-cylinder gap. Transfer pressure standards up to 1.5 GPa are developed on the basis of modern 1.5 GPa pressure transducers. This project shall solve a discrepancy between the growing needs of the industry demanding precise traceable calibrations of the high pressure transducers and the absence of adequate primary standards for pressures higher than 1 GPa in the European Union today.

Sabuga, Wladimir; Pražák, Dominik; Rabault, Thierry

2014-08-01

338

High pressure Hugoniot measurements using converging shocks  

Microsoft Academic Search

Plate impact experiments are a powerful tool in equation of state development, but are inherently limited by the range of impact velocities accessible to the facility. In an effort to dramatically increase the range of pressures which can be studied with available impact velocities, a new experimental technique is examined. The target plate is replaced by a composite assembly consisting

J. L. Brown; G. Ravichandran; W. D. Reinhart; W. M. Trott

2011-01-01

339

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

PubMed

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

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

2013-11-01

340

High pressure, high temperature studies of methane-water mixtures  

NASA Astrophysics Data System (ADS)

Recently, experiments conducted on methane at high pressures and temperatures have produced evidence to suggest that abiogenic processes in the upper mantle have the potential to yield longer-chain hydrocarbons, including petroleum spectrum hydrocarbons. We have conducted in-situ Raman scattering measurements in the laser-heated diamond-anvil cell on methane-water mixtures to characterize how an oxidizing agent, water, would alter methane-methane interactions from those observed in the pure phase. Results from laser heating showed diamond and hydrogen formation and complex hydrocarbon production in the presence of water, suggesting that abiogenic reactions of methane to form heavy hydrocarbons can occur in hydrous environments within the Earth.

Hittinger, T. J.; Goncharov, A. F.; Dalton, D. A.; McWilliams, R. S.; Mahmood, M.

2010-12-01

341

Newly Diagnosed with High Blood Pressure? 3 Factors Affect Prognosis  

MedlinePLUS

... this page, please enable JavaScript. Newly Diagnosed With High Blood Pressure? 3 Factors Affect Prognosis Systolic reading of 150 ... February 5, 2015 Related MedlinePlus Pages Heart Attack High Blood Pressure Stroke THURSDAY, Feb. 5, 2015 (HealthDay News) -- Prompt ...

342

Hydraulic analysis aids high-pressure system design  

Microsoft Academic Search

Transient hydraulic analysis of high pressure gas transmission systems can be used to investigate various areas during design engineering. Practical results can be obtained that give insight into the characteristics of the transportation systems. High-pressure gas transmission systems have particular characteristics that should be considered in a transient hydraulic analysis: prediction of physical and thermodynamic gas properties, tendency for significant

T. E. Stripling; K. Dillon; A. U. Khan

1985-01-01

343

Effects of high pressure on meat: A review  

Microsoft Academic Search

Extensive investigations in the last decade have revealed the potential benefits of high pressure processing (100–800 MPa) for the preservation and modification of foods. Simultaneously, a few pressurised foods have become commercially available in Japan, Europe and the USA. In the present review, the basic principles underlying the effects of high pressure on food constituents and quality attributes are first

J. Claude Cheftel; Joseph Culioli

1997-01-01

344

Insulinemia: relation with obesity and high blood pressure  

Microsoft Academic Search

Blood insulin levels in obese subjects with high blood pressure (BP) are higher than normal and are associated with changes in fats metabolism. Subjects with high blood pressure show primary insulin resistance and their blood insulin values show variations according to the severity of hypertension.Forty subjects aged between 20 and 45 years were selected by means of inquiry to detect

Vera R. Omaira; Juan R. Carballo; Elinor Flores; Miguel Espinoza; Freddy Contreras; Julio Cabrera; Manuel Velasco

2002-01-01

345

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

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

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

346

6. Fire Protection (high pressure), view to the east. Located ...  

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

6. Fire Protection (high pressure), view to the east. Located on the pipe floor between Unit 3 and Unit 4, the high pressure CO2 tanks are connected to the generator barrel of all four units. - Washington Water Power Clark Fork River Cabinet Gorge Hydroelectric Development, Powerhouse, North Bank of Clark Fork River at Cabinet Gorge, Cabinet, Bonner County, ID

347

Insomnia Linked to High Blood Pressure in Study  

MedlinePLUS

... please enable JavaScript. Insomnia Linked to High Blood Pressure in Study But finding doesn't prove cause- ... January 26, 2015 Related MedlinePlus Pages High Blood Pressure Insomnia MONDAY, Jan. 26, 2015 (HealthDay News) -- People ...

348

Journey to the Center of the Earth: Exploring High Pressure  

SciTech Connect

The deeper we go into the Earth, the higher the pressure. At the pressures found within the center of our planet, minerals do not simply compress. Pressure dramatically alters all materials properties, in the process creating numerous novel phases not found on the surface. This lecture will describe how we simulate the conditions found in planetary interiors in the lab, what kinds of new behavior we find, and how these observations can explain what is going on within the Earth. High pressure explorations also lead to discoveries of novel materials with potential for practical applications in our low-pressure, environment.

Mao, Wendy

2009-09-29

349

Strong environmental tolerance of Artemia under very high pressure  

NASA Astrophysics Data System (ADS)

It was shown by the present authors group that a tardigrade in its tun-state can survive after exposed to 7.5 GPa for 13 hours. We have extended this experiment to other tiny animals searching for lives under extreme conditions of high hydrostatic pressure. Artemia, a kind of planktons, in its dried egg-state have strong environmental tolerance. Dozens of Artemia eggs were sealed in a small Teflon capsule together with a liquid pressure medium, and exposed to the high hydrostatic pressure of 7.5 GPa. After the pressure was released, they were soaked in seawater to observe hatching rate. It was proved that 80-90% of the Artemia eggs were alive and hatched into Nauplii after exposed to the maximum pressure of 7.5 GPa for up to 48 hours. Comparing with Tardigrades, Artemia are four-times stronger against high pressure.

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

2010-03-01

350

High-Pressure Oxygen Generation for Outpost EVA Study  

NASA Technical Reports Server (NTRS)

The amount of oxygen consumption for crew extravehicular activity (EVA) in future lunar exploration missions will be significant. Eight technologies to provide high pressure EVA O2 were investigated. They are: high pressure O2 storage, liquid oxygen (LOX) storage followed by vaporization, scavenging LOX from Lander followed by vaporization, LOX delivery followed by sorption compression, water electrolysis followed by compression, stand-alone high pressure water electrolyzer, Environmental Control and Life Support System (ECLSS) and Power Elements sharing a high pressure water electrolyzer, and ECLSS and In-Situ Resource Utilization (ISRU) Elements sharing a high pressure electrolyzer. A trade analysis was conducted comparing launch mass and equivalent system mass (ESM) of the eight technologies in open and closed ECLSS architectures. Technologies considered appropriate for the two architectures were selected and suggested for development.

Jeng, Frank F.; Conger, Bruce; Ewert, Michael K.; Anderson, Molly S.

2009-01-01

351

High-pressure phase transitions in adamantane  

NASA Astrophysics Data System (ADS)

We report angle dispersive X-ray diffraction (ADXRD) measurements on adamantane carried out at SPRING-8 to the pressures of 25 GPa. The tetragonal phase observed at 0.5 GPa remains stable up to 12.5 GPa. In this pressure range the intermolecular hydrogen separation reduces from 2.37 to1.87 Å with relative angle of rotation of the two molecules increasing from 8.5° to 10.5° in agreement with values from energy minimization. At 16 GPa, the diffraction pattern could be indexed either by a tetragonal or a monoclinic cell. Beyond 22 GPa only monoclinic cell indexes the patterns. The present findings corroborate the earlier Raman results.

Vijayakumar, V.; Garg, Alka B.; Godwal, B. K.; Sikka, S. K.

2000-11-01

352

High Pressure Hugoniot Measurements Using Converging Shocks  

Microsoft Academic Search

\\u000a Plate impact experiments are a powerful tool in equation of state development, but are inherently limited by the range of\\u000a impact velocities accessible to the gun. In an effort to dramatically increase the range of pressures which can be studied\\u000a with available impact velocities, a new experimental technique is being developed. The possibility of using converging shock\\u000a waves to produce

J. L. Brown; G. Ravichandran

353

Is exercise good for high blood pressure?  

Microsoft Academic Search

Ten men with uncomplicated essential hypertension (mean standing blood pressure 165\\/109 mm Hg) and 10 normal controls matched for age and weight were studied for the hypotensive potential of moderate exercise. Tests were conducted on a treadmill set to induce a steady heart rate of 120 beats\\/min and performed over five 10-minute periods separated by three minutes' rest and finishing

R G Wilcox; T Bennett; A M Brown; I A Macdonald

1982-01-01

354

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

Code of Federal Regulations, 2012 CFR

...containment systems and hoses to and from alkylene oxide service. 153.1011 Section 153...containment systems and hoses to and from alkylene oxide service. (a) The person in charge...shall make sure that: (1) No alkylene oxide is loaded into a containment system...

2012-10-01

355

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

Code of Federal Regulations, 2014 CFR

...containment systems and hoses to and from alkylene oxide service. 153.1011 Section 153...containment systems and hoses to and from alkylene oxide service. (a) The person in charge...shall make sure that: (1) No alkylene oxide is loaded into a containment system...

2014-10-01

356

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

Code of Federal Regulations, 2013 CFR

...containment systems and hoses to and from alkylene oxide service. 153.1011 Section 153...containment systems and hoses to and from alkylene oxide service. (a) The person in charge...shall make sure that: (1) No alkylene oxide is loaded into a containment system...

2013-10-01

357

46 CFR 76.10-10 - Fire station hydrants, hose and nozzles-T/ALL.  

Code of Federal Regulations, 2010 CFR

...station hydrants, hose and nozzles-T/ALL. 76.10-10 Section 76.10-10...station hydrants, hose and nozzles-T/ALL. (a) The size of fire hydrants...required at each fire station; however, if all such stations can be satisfactorily...

2010-10-01

358

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

Microsoft Academic Search

A porous tube, comprised of a resin-coated woven fabric has recently been used as an effective component for use in intake systems of internal combustion engines to reduce the intake noise. For the prediction of the acoustic performance of an engine intake system with a porous woven hose, the acoustic wall impedance of the hose must be known. However, the

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

2003-01-01

359

46 CFR 167.45-25 - Fire mains and hose connections.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Fire mains and hose connections. 167.45-25...Requirements § 167.45-25 Fire mains and hose connections. All pipes used as mains for conducting water from fire pumps on nautical school...

2012-10-01

360

46 CFR 167.45-25 - Fire mains and hose connections.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Fire mains and hose connections. 167.45-25...Requirements § 167.45-25 Fire mains and hose connections. All pipes used as mains for conducting water from fire pumps on nautical school...

2010-10-01

361

46 CFR 167.45-25 - Fire mains and hose connections.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Fire mains and hose connections. 167.45-25...Requirements § 167.45-25 Fire mains and hose connections. All pipes used as mains for conducting water from fire pumps on nautical school...

2011-10-01

362

46 CFR 28.315 - Fire pumps, fire mains, fire hydrants, and fire hoses.  

Code of Federal Regulations, 2013 CFR

... false Fire pumps, fire mains, fire hydrants, and fire hoses...28.315 Fire pumps, fire mains, fire hydrants, and fire hoses...must be capable of delivering water simultaneously from the two...to permit energizing the fire main from the operating station...

2013-10-01

363

46 CFR 167.45-25 - Fire mains and hose connections.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Fire mains and hose connections. 167.45-25...Requirements § 167.45-25 Fire mains and hose connections. All pipes used as mains for conducting water from fire pumps on nautical school...

2013-10-01

364

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

Microsoft Academic Search

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

2000-01-01

365

Effect of high pressure on hydrocarbon-degrading bacteria  

PubMed Central

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

2014-01-01

366

High-pressure applications in medicine and pharmacology  

NASA Astrophysics Data System (ADS)

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

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

2004-04-01

367

Fate of Staphylococcus aureus in Cheese Treated by Ultrahigh Pressure Homogenization and High Hydrostatic Pressure  

Microsoft Academic Search

We evaluated the influence of ultrahigh pressure ho- mogenization (UHPH) treatment applied to milk con- taining Staphylococcus aureus CECT 976 before cheese making, and the benefit of applying a further high hy- drostatic pressure (HHP) treatment to cheese. The evo- lution of Staph. aureus counts during 30 d of storage at 8°C and the formation of staphylococcal enterotoxins were also

T. López-Pedemonte; A. X. Roig-Sagués; B. Guamis

2006-01-01

368

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

Code of Federal Regulations, 2010 CFR

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

2010-10-01

369

Cryogenic Transport of High-Pressure-System Recharge Gas  

NASA Technical Reports Server (NTRS)

A method of relatively safe, compact, efficient recharging of a high-pressure room-temperature gas supply has been proposed. In this method, the gas would be liquefied at the source for transport as a cryogenic fluid at or slightly above atmospheric pressure. Upon reaching the destination, a simple heating/expansion process would be used to (1) convert the transported cryogenic fluid to the room-temperature, high-pressure gaseous form in which it is intended to be utilized and (2) transfer the resulting gas to the storage tank of the system to be recharged. In conventional practice for recharging high-pressure-gas systems, gases are transported at room temperature in high-pressure tanks. For recharging a given system to a specified pressure, a transport tank must contain the recharge gas at a much higher pressure. At the destination, the transport tank is connected to the system storage tank to be recharged, and the pressures in the transport tank and the system storage tank are allowed to equalize. One major disadvantage of the conventional approach is that the high transport pressure poses a hazard. Another disadvantage is the waste of a significant amount of recharge gas. Because the transport tank is disconnected from the system storage tank when it is at the specified system recharge pressure, the transport tank still contains a significant amount of recharge gas (typically on the order of half of the amount transported) that cannot be used. In the proposed method, the cryogenic fluid would be transported in a suitably thermally insulated tank that would be capable of withstanding the recharge pressure of the destination tank. The tank would be equipped with quick-disconnect fluid-transfer fittings and with a low-power electric heater (which would not be used during transport). In preparation for transport, a relief valve would be attached via one of the quick-disconnect fittings (see figure). During transport, the interior of the tank would be kept at a near-ambient pressure far below the recharge pressure. As leakage of heat into the tank caused vaporization of the cryogenic fluid, the resulting gas would be vented through the relief valve, which would be set to maintain the pressure in the tank at the transport value. Inasmuch as the density of a cryogenic fluid at atmospheric pressure greatly exceeds that of the corresponding gas in a practical high-pressure tank at room temperature, a tank for transporting a given mass of gas according to the proposed method could be smaller (and, hence, less massive) than is a tank needed for transporting the same mass of gas according to the conventional method.

Ungar, Eugene K,; Ruemmele, Warren P.; Bohannon, Carl

2010-01-01

370

Fiber optic photoelastic pressure sensor for high temperature gases  

NASA Technical Reports Server (NTRS)

A novel fiber optic pressure sensor based on the photoelastic effects has been developed for extremely high temperature gases. At temperatures varying from 25 to 650 C, the sensor experiences no change in the peak pressure of the transfer function and only a 10 percent drop in dynamic range. Refinement of the sensor has resulted in an optoelectronic interface and processor software which can calculate pressure values within 1 percent of full scale at any temperature within the full calibrated temperature range.

Wesson, Laurence N.; Redner, Alex S.; Baumbick, Robert J.

1990-01-01

371

Superconductivity in URu2Si2 Under High Pressure  

NASA Astrophysics Data System (ADS)

Magnetization measurements of heavy fermion superconductor URu2Si2 have been performed under hydrostatic pressures. The superconducting transition temperature decreases linearly with pressure up to 0.8 GPa and disappears around 1.2 GPa. The hysteretic magnetization shows charasteristic behaviors at high pressures, suggesting that the pinning properties change due to the switch of the normal state from the hidden order phase to the antiferromagnetic phase.

Tenya, K.; Kawasaki, I.; Amitsuka, H.; Yokoyama, M.; Tateiwa, N.; Kobayashi, T. C.

2006-08-01

372

Theoretical Thermodynamics of Mixtures at High Pressures  

NASA Technical Reports Server (NTRS)

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

Hubbard, W. B.

1985-01-01

373

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

SciTech Connect

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

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

2013-02-15

374

Laboratory investigation of high pressure survival in Shewanella oneidensis MR-1 into the gigapascal pressure range  

PubMed Central

The survival of Shewanella oneidensis MR-1 at up to 1500 MPa was investigated by laboratory studies involving exposure to high pressure followed by evaluation of survivors as the number (N) of colony forming units (CFU) that could be cultured following recovery to ambient conditions. Exposing the wild type (WT) bacteria to 250 MPa resulted in only a minor (0.7 log N units) drop in survival compared with the initial concentration of 108 cells/ml. Raising the pressure to above 500 MPa caused a large reduction in the number of viable cells observed following recovery to ambient pressure. Additional pressure increase caused a further decrease in survivability, with approximately 102 CFU/ml recorded following exposure to 1000 MPa (1 GPa) and 1.5 GPa. Pressurizing samples from colonies resuscitated from survivors that had been previously exposed to high pressure resulted in substantially greater survivor counts. Experiments were carried out to examine potential interactions between pressure and temperature variables in determining bacterial survival. One generation of survivors previously exposed to 1 GPa was compared with WT samples to investigate survival between 37 and 8°C. The results did not reveal any coupling between acquired high pressure resistance and temperature effects on growth. PMID:25452750

Hazael, Rachael; Foglia, Fabrizia; Kardzhaliyska, Liya; Daniel, Isabelle; Meersman, Filip; McMillan, Paul

2014-01-01

375

Criterion for Identifying Vortices in High-Pressure Flows  

NASA Technical Reports Server (NTRS)

A study of four previously published computational criteria for identifying vortices in high-pressure flows has led to the selection of one of them as the best. This development can be expected to contribute to understanding of high-pressure flows, which occur in diverse settings, including diesel, gas turbine, and rocket engines and the atmospheres of Jupiter and other large gaseous planets. Information on the atmospheres of gaseous planets consists mainly of visual and thermal images of the flows over the planets. Also, validation of recently proposed computational models of high-pressure flows entails comparison with measurements, which are mainly of visual nature. Heretofore, the interpretation of images of high-pressure flows to identify vortices has been based on experience with low-pressure flows. However, high-pressure flows have features distinct from those of low-pressure flows, particularly in regions of high pressure gradient magnitude caused by dynamic turbulent effects and by thermodynamic mixing of chemical species. Therefore, interpretations based on low-pressure behavior may lead to misidentification of vortices and other flow structures in high-pressure flows. The study reported here was performed in recognition of the need for one or more quantitative criteria for identifying coherent flow structures - especially vortices - from previously generated flow-field data, to complement or supersede the determination of flow structures by visual inspection of instantaneous fields or flow animations. The focus in the study was on correlating visible images of flow features with various quantities computed from flow-field data.

Bellan, Josette; Okong'o, Nora

2007-01-01

376

Studies of Alkali Sorption Kinetics for Pressurized Fluidized Bed Combustion by High Pressure Mass Spectrometry  

SciTech Connect

This work describes the first approach to use High Pressure Mass Spectrometry (HPMS) for the quantification and analysis of alkali species in a gas stream downstream a sorbent bed of different tested alumosilicates.

Wolf, K.J.; Willenborg, W.; Fricke, C.; Prikhodovsky, A.; Hilpert, K.; Singheiser, L.

2002-09-20

377

Germination of vegetable seeds exposed to very high pressure  

NASA Astrophysics Data System (ADS)

Effects of high hydrostatic pressure were investigated on vegetable seeds in the GPa range to examine the potentialities of breed improvement by high-pressure processing. Specimens of several seeds of broccoli (Brassica oleracea var. italica), Turnip leaf (Brassica rapa var. perviridis) and Potherb Mustard (Brassica rapa var. nipposinica) were put in a teflon capsule with liquid high pressure medium, fluorinate, and inserted into a pyrophillite cube. By using a cubic anvil press a hydrostatic pressure of 5.5 GP a was applied to these seeds for 15 minutes. After being brought back to ambient pressure, they were seeded on humid soil in a plant pot. Many of these vegetable seeds began to germinate within 6 days after seeded.

Mori, Y.; Yokota, S.; Ono, F.

2012-07-01

378

Underground storage systems for high-pressure air and gases  

NASA Technical Reports Server (NTRS)

This paper is a discussion of the safety and cost of underground high-pressure air and gas storage systems based on recent experience with a high-pressure air system installed at Moffett Field, California. The system described used threaded and coupled oil well casings installed vertically to a depth of 1200 ft. Maximum pressure was 3000 psi and capacity was 500,000 lb of air. A failure mode analysis is presented, and it is shown that underground storage offers advantages in avoiding catastrophic consequences from pressure vessel failure. Certain problems such as corrosion, fatigue, and electrolysis are discussed in terms of the economic life of such vessels. A cost analysis shows that where favorable drilling conditions exist, the cost of underground high-pressure storage is approximately one-quarter that of equivalent aboveground storage.

Beam, B. H.; Giovannetti, A.

1975-01-01

379

Rotational viscometer for high-pressure high-temperature fluids  

DOEpatents

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

Carr, Kenneth R. (Knoxville, TN)

1985-01-01

380

New Iron Hydrides under High Pressure.  

PubMed

The Fe-H system has been investigated by combined x-ray diffraction studies and total energy calculations at pressures up to 136 GPa. The experiments involve laser annealing of hydrogen-embedded iron in a diamond anvil cell. Two new FeH_{x} compounds, with x?2 and x=3, are discovered at 67 and 86 GPa, respectively. Their crystal structures are identified (unit cell and Fe positional parameters from x-ray diffraction, H positional parameters from ab initio calculations) as tetragonal with space group I4/mmm for FeH_{?2} and as simple cubic with space group Pm3[over ¯]m for FeH_{3}. Large metastability regimes are observed that allowed to measure the P(V) equation of state at room temperature of FeH, FeH_{?2}, and FeH_{3}. PMID:25615354

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

2014-12-31

381

New Iron Hydrides under High Pressure  

NASA Astrophysics Data System (ADS)

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

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

2014-12-01

382

High pressure compressor component performance report  

NASA Technical Reports Server (NTRS)

A compressor optimization study defined a 10 stage configuration with a 22.6:1 pressure ratio, an adiabatic efficiency goal of 86.1%, and a polytropic efficiency of 90.6%; the corrected airflow is 53.5 kg/s. Subsequent component testing included three full scale tests: a six stage rig test, a 10 stage rig test, and another 10 stage rig test completed in the second quarter of 1982. Information from these tests is used to select the configuration for a core engine test and an integrated core/low spool test. The test results will also provide data base for the flight propulsion system. The results of the test series with both aerodynamic and mechanical performance of each compressor build are presented. The second 10 stage compressor adiabatic efficiency was 0.848 at a cruise operating point versus a test goal of 0.846.

Cline, S. J.; Fesler, W.; Liu, H. S.; Lovell, R. C.; Shaffer, S. J.

1983-01-01

383

A high-temperature wideband pressure transducer  

NASA Technical Reports Server (NTRS)

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

Zuckerwar, A. J.

1977-01-01

384

A novel FBG pressure sensor with high sensitivity  

Microsoft Academic Search

A high-sensitivity fiber Bragg grating (FBG) pressure sensor has been designed and studied. Confining some gas inside a glass cylinder with a close glass piston which can move smoothly along the cylinder, and sticking two ends of a fiber Bragg grating on the outer side of the cylinder and piston respectively. The variation of the external pressure results in the

Shiya He; Shuyang Hu; Dawei Tian; Kuanxin Yu; Qida Zhao; Jinfeng Zhou; Li Wang

2005-01-01

385

High-pressure and temperature investigations of energetic materials  

NASA Astrophysics Data System (ADS)

Static high-pressure measurements are extremely useful for obtaining thermodynamic and phase stability information from a wide variety of materials. However, studying energetic materials can be challenging when extracting information from static high-pressure measurements. Energetic materials are traditionally C, H, N, O compounds with low crystalline symmetry, producing weak signal in commonly performed x-ray diffraction measurements. The small sample volume available in a static high-pressure cell exacerbates this issue. Additionally, typical hydrostatic compression media, such as methanol/ethanol, may react with many energetic materials. However, characterization of their thermodynamic parameters and phase stability is critical to understanding explosive performance and sensitivity. Crystalline properties, such as bulk modulus and thermal expansion, are necessary to accurately predict the behaviour of shocked solids using hydrodynamic codes. In order to obtain these values, equations of state of various energetic materials were investigated using synchrotron angle-dispersive x-ray diffraction experiments at static high-pressure and temperature. Intense synchrotron radiation overcomes the weak x-ray scattering of energetic materials in a pressure cell. The samples were hydrostatically compressed using a non-reactive hydrostatic medium and heated using a heated diamond anvil cell. Pressure - volume data for the materials were fit to the Birch-Murnaghan and Vinet formalisms to obtain bulk modulus and its first pressure derivative. Temperature - volume data at ambient pressure were fit to obtain the volume thermal expansion coefficient. Data from several energetic materials will be presented and compared.

Gump, J. C.

2014-05-01

386

Catalytic gasification of coal with high-pressure steam  

Microsoft Academic Search

Simultaneous equilibria for steam-conversion of coal were computed for temperatures from 800 to 1100 K and for pressures to 600 bar. Real behavior of the gases was taken into account using the equation of state by Redlich and Kwong. An apparatus is described for investigating the gasification of lignite and bituminous coke at high pressures. Considerable accelerations of the reaction

S. Peter; G. Woyke; G. Baumgaertel

1978-01-01

387

Neutron scattering at high pressure D. B. McWhan  

E-print Network

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

388

Remission of High Blood Pressure Reverses Arterial Potassium Channel Alterations  

Microsoft Academic Search

Rat arterial muscle cells show an elevated Ca2+- dependent K+ efflux during the established phase of hyperten- sion. This association of enhanced K+ efflux with high arterial pressure implies that changes of in vivo blood pressure can alter the level of K+ channel current in arterial membranes. We directly tested this hypothesis by comparing K + current density between patch-clamped

Nancy J. Rusch; Anne M. Runnells

389

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

Microsoft Academic Search

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

J. C. Jamieson

1963-01-01

390

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

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

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

391

42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...  

Code of Federal Regulations, 2013 CFR

...supplied-air respirators, demand and pressure-demand classes; test requirements...supplied-air respirators, demand and pressure-demand classes; test requirements...test will be conducted at the minimum pressure with the maximum hose length and...

2013-10-01

392

42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...  

Code of Federal Regulations, 2012 CFR

...supplied-air respirators, demand and pressure-demand classes; test requirements...supplied-air respirators, demand and pressure-demand classes; test requirements...test will be conducted at the minimum pressure with the maximum hose length and...

2012-10-01

393

42 CFR 84.163 - Man test for gases and vapors; Type C supplied-air respirators, demand and pressure-demand...  

Code of Federal Regulations, 2014 CFR

...supplied-air respirators, demand and pressure-demand classes; test requirements...supplied-air respirators, demand and pressure-demand classes; test requirements...test will be conducted at the minimum pressure with the maximum hose length and...

2014-10-01

394

Replacement for a Flex Hose Coating at the Space Shuttle Launch Pad  

NASA Technical Reports Server (NTRS)

Aerocoat AR-7 is a coating that has been used to protect stainless steel flex hoses at NASA's Kennedy Space Center launch complex and hydraulic lines of the mobile launch platform (MLP). This coating has great corrosion control performance and low temperature application. AR-7 was developed by NASA and produced exclusively for NASA but its production has been discontinued due to its high content of volatile organic compounds (VOC) and significant environmental impact. The purpose of this project was to select and evaluate candidate coatings to find a replacement coating that is more environmentally friendly, with similar properties to AR-7. No coatings were identified that perform the same as AR-7 in all areas. Candidate coatings failed in comparison to AR-7 in salt fog, beachside atmospheric exposure, pencil hardness, Mandrel bend, chemical compatibility, adhesion, and ease of application tests. However, two coatings were selected for further evaluation.

Whitten, Mary; Vinje, Rubiela; Curran, Jerome; Meneghelli, Barry; Calle, Luz Marina

2009-01-01

395

Evaluation of candidate alloys for the construction of metal flex hoses in the STS launch environment  

NASA Technical Reports Server (NTRS)

Various vacuum jacketed cryogenic supply lines at the Shuttle launch site use convoluted flexible expansion joints. The atmosphere at the launch site has a very high salt content, and during a launch fuel combustion products include hydrochloric acid. This extremely corrosive environment has caused pitting corrosion failure in the flex hoses, which were made out of 304L stainless steel. A search was done to find a more corrosion resistant replacement material. Nineteen metal alloys were tested. Tests which were performed include electrochemical corrosion testing, accelerated corrosion testing in a salt fog chamber, long term exposure at the beach corrosion testing site, and pitting corrosion tests in ferric chloride solution. Based on the results, the most corrosion resistant alloys were found to be, in order, Hastelloy C-22, Inconel 625, Hastelloy C-276, Hastelloy C-4, and Inco Alloy G-3. Of these top five alloys, the Hastelloy C-22 stands out as being the best of the alloys tested.

Macdowell, Louis G., III; Ontiveros, Cordelia

1988-01-01

396

Linear ruby scale and one megabar. [high pressure fluorescence  

NASA Technical Reports Server (NTRS)

The accuracy and validity of certain techniques used in studying high-pressure transitions have been investigated. Experiments which place upper limits of about 20 GPa and about 50 GPa on pressures practically attainable using uniaxial supported opposed anvil devices with tungsten carbide pistons and uniaxial opposed flat anvil diamond devices, respectively, are reported. Direct static determinations of the transition pressures of GaP by two different methods are described. The values obtained indicate that the linear ruby scale increasingly overestimates the transition pressure as the pressure rises above 10 GPa. It is further shown that the use of shock-based marker materials, such as silver, as the basis of pressure measurement in X-ray diffraction studies leads to bulk moduli of cubic carbides which are in extreme disagreement with expected values.

Ruoff, A. L.

1979-01-01

397

Energy Systems High Pressure Test Laboratory (Fact Sheet)  

SciTech Connect

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

2011-10-01

398

Applications and development of high pressure PEM systems  

SciTech Connect

Many portable fuel cell applications require high pressure hydrogen, oxygen, or both. High pressure PEM systems that were originally designed and developed primarily for aerospace applications are being redesigned for use in portable applications. Historically, applications can be broken into weight sensitive and weight insensitive cell stack designs. Variants of the weight sensitive designs have been considered to refill oxygen bottles for space suits, to provide oxygen for space shuttle, to provide oxygen and/or reboost propellants to the space station, and to recharge oxygen bottles for commercial aviation. A long operating history has been generated for weight insensitive designs that serve as oxygen generators for submarines. Exciting future vehicle concepts and portable applications are enabled by carefully designing lightweight stacks which do not require additional pressure containment. These include high altitude long endurance solar rechargeable aircraft and airships, water refuelable spacecraft, and a variety of field portable systems. High pressure electrolyzers can refill compressed hydrogen storage tanks for fuel cell powered vehicles or portable fuel cells. Hamilton Standard has demonstrated many high pressure PEM water electrolyzer designs for a variety of applications. Electrolyzers with operational pressures up to 3000 psi (20.7 MPa) are currently used for US Navy submarine oxygen generators. An aerospace version has been demonstrated in the Integrated Propulsion Test Article (IPTA) program. Electrolyzers with operational pressures up to 6000 psi (41.4 MPa) have also been demonstrated in the High Pressure Oxygen Recharge System (HPORS). Onboard oxygen generator systems (OBOGS) that generate up to 2000 psi (13.8 MPa) oxygen and refill breathable oxygen tanks for commercial aviation have been designed and successfully demonstrated. Other hardware applications that require high pressure PEM devices are related to these proven applications.

Leonida, A; Militsky, F; Myers, B; Weisberg, A H

1999-06-01

399

Pressure sensitive paint suitable to high Knudsen number regime  

NASA Astrophysics Data System (ADS)

Pressure sensitive paint (PSP) techniques have the capability to be applied to high Knudsen number flows, such as low density gas flows, micro-flows, and so on. In this study, to inspect the feasibility of PSP for measurement of pressure on a solid surface in high Knudsen number flows, the fundamental properties of PSPs are examined, especially in the range of pressure below 130 Pa (about 1 Torr). As a result, it is clarified that the PSP using poly(TMSP) as a binder and using PdOEP or PdTFPP as a luminophore has very high sensitivity to oxygen pressure under low pressure conditions below 130 Pa. Pressure sensitivity to nitrogen monoxide is also examined for the above PSPs, and it is clarified that PdTFPP bound by poly(TMSP) has very high sensitivity while PdOEP has very low sensitivity to nitrogen monoxide. The combination of the PdTFPP-based PSP and NO-LIF technique enables composite measurement of flow field structures and surface pressure in the high-Kn regime.

Mori, Hideo; Niimi, Tomohide; Hirako, Madoka; Uenishi, Hiroyuki

2006-06-01

400

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

E-print Network

on the temperature of the electronic head. Finally, the total pressure distorts Elect~ical Feedthrough~ Magnetic Core LVDT Bushing Extension Rod High Temperature Bath Overpressure Protection Collar Post-Base Diaphragm Sample Inlet Figure 7...). Each of these detection systems converts the mechanical distortion of the sensing element to a change in an electrical property which can be measured. The strain gauge as described by Higdon et al. (1960), for example, consists of a length of fine...

Childers, Laren Paul

2012-06-07

401

HIGH PRESSURE COAL COMBUSTION KINETICS PROJECT  

SciTech Connect

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

2001-09-15

402

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

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

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

403

High pressure working mode of hollow cathode arc discharges  

NASA Technical Reports Server (NTRS)

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

Minoo, H.; Popovici, C.

1985-01-01

404

High Blood Pressure in Pregnancy - Multiple Languages: MedlinePlus  

MedlinePLUS

... français) Hindi (??????) Japanese (???) Korean (???) Marshallese (kajin Majöl) Portuguese (português) Russian (???????) Somali (af ... Bilingual PDF Health Information Translations Return to top Marshallese (kajin Majöl) High Blood Pressure in Pregnancy Elañe ...

405

High-pressure LOX/CH4 injector program  

NASA Technical Reports Server (NTRS)

Two injector types, either coaxial or impinging elements, for high pressure LOX/CH4 operation with an existing 40K chamber are examined. A comparison is presented. The detailed fabrication drawings and supporting analysis are presented.

Wheeler, D. B.; Kirby, F. M.

1979-01-01

406

5. INTERIOR, TWO 5' X 6' HIGH PRESSURE EMERGENCY GATES, ...  

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

5. INTERIOR, TWO 5' X 6' HIGH PRESSURE EMERGENCY GATES, FOR BUREAU OF RECLAIMATION, WITH HYDRAULIC HOISTS, INSIDE OF MACHINE SHOP (CA 1930S). - Hardie-Tynes Manufacturing Company, Workshop, 800 Twenty-eighth Street North, Birmingham, Jefferson County, AL

407

High-pressure liquid chromatography of aromatic amines  

NASA Technical Reports Server (NTRS)

Analysis made on commercially available liquid chromatograph demonstrates high-pressure liquid chromatographic conditions for separation of approximately 50 aromatic amines ranging from simple aniline derivatives to complex multiring di- and tri-amines.

Young, P. R.

1979-01-01

408

Crystallization and vitrification of ethanol at high pressures.  

PubMed

We present the high pressure (up to 3 GPa) dielectric spectroscopy study of ethanol in supercooled liquid and solid states. It was found that ethanol can be obtained in the glassy form by relatively slow cooling in the pressure range below 1.5 GPa. Glassy dynamics of ethanol is dominated by hydrogen bonds which cause rise of fragility index with pressure rising and relatively slow increase of glassification temperature. The termination of ethanol galssification at 1.5 GPa is related to the phase transition of ethanol in this pressure range to the disordered crystal structure which allows easy crystallization of ethanol at high pressures. Dielectric spectroscopy of solid phases of ethanol reveals the presence of molecular motion in both of them in the temperature range close to the melting curve but demonstrates different molecular dynamics in the two solid phases of ethanol. PMID:25416895

Kondrin, M V; Pronin, A A; Brazhkin, V V

2014-11-21

409

Low Cost, High Efficiency, High Pressure Hydrogen Storage  

SciTech Connect

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

2010-03-31

410

High blood pressure, oxygen radicals and antioxidants: Etiological relationships  

Microsoft Academic Search

This hypothesis proposes that high blood pressure is a pathological state associated with a loss of the balance between pro-oxidation and antioxidation, energy depletion, and accelerated aging in the target organs, such as heart, kidney and brain. Different nutritional, environmental, pharmacological factors and\\/or associated pathologies (diabetes, arteriosclerosis, cancer, alcoholism, etc.), and\\/or genetic components, can induce high blood pressure by breaking

D. Romero-Alvira; E. Roche

1996-01-01

411

Pulse plasma carburizing and high pressure gas quenching -- Industrial applications  

SciTech Connect

Pulse plasma carburizing with high pressure gas quenching up to 20 bar is the newly developed case hardening process now available in production size equipment. The first part of results demonstrates the tremendous potential of high pressure gas quenching for successful hardening of case hardening steels. The second part opens a window to glance at the pulse plasma carburizing of complex shaped parts. Both processes improve economical data and performance of carburizing processes.

Preisser, F.; Schnatbaum, F. [ALD Vacuum Technologies GmbH, Erlensee (Germany)

1995-12-31

412

High hydrostatic pressure technology in dairy processing: a review  

Microsoft Academic Search

Consumers demand high quality foods, which are fresh, tasty and nutritious; this has created considerable interest in the\\u000a development of new food processing techniques. Presently, non-thermal techniques, including high hydrostatic pressure (HHP),\\u000a are regarded with special interest by the food industry. Pressure ranges between 100 and 1200 MPa have been considered as\\u000a effective to inactivate microorganisms including food-borne pathogens. HHP also

Rekha Chawla; Girdhari Ramdass Patil; Ashish Kumar Singh

2011-01-01

413

High pressure and multiferroics materials: a happy marriage  

PubMed Central

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

Gilioli, Edmondo; Ehm, Lars

2014-01-01

414

High pressure and multiferroics materials: a happy marriage.  

PubMed

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

Gilioli, Edmondo; Ehm, Lars

2014-11-01

415

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

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Control of the pressure of gas delivered from high-pressure distribution...SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS...192.197 Control of the pressure of gas delivered from high-pressure...

2010-10-01

416

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

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Control of the pressure of gas delivered from high-pressure distribution systems. 192.197 Section...Pipeline Components § 192.197 Control of the pressure of gas delivered from high-pressure...

2012-10-01

417

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

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Control of the pressure of gas delivered from high-pressure distribution systems. 192.197 Section...Pipeline Components § 192.197 Control of the pressure of gas delivered from high-pressure...

2011-10-01

418

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

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Control of the pressure of gas delivered from high-pressure distribution systems. 192.197 Section...Pipeline Components § 192.197 Control of the pressure of gas delivered from high-pressure...

2013-10-01

419

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

NASA Astrophysics Data System (ADS)

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

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

2014-04-01

420

Delta wing surface pressures for high angle of attack maneuvers  

NASA Technical Reports Server (NTRS)

A wind tunnel experiment was performed on a delta wing with a leading edge sweep of 70 deg. Unsteady pressures were measured on the suction surface of the wing as it was oscillated from 0-30 deg, and 2-60 deg angle-of-attack. Pressure coefficients were measured at different surface locations for two pitch rates. Static pressure measurements were also obtained for comparison with the dynamic results. The Reynolds number was fixed at 420,000, based on the centerline chord length. Pressure measurements were made from 35-90 percent of the chord, along a ray from the apex at 60 percent of the local semispan. Spanwise measurements were also made at a constant chord location, x/c = 75 percent from the apex. The unsteady pressure data over the 0-30 deg angle-of-attack range showed pressures fluctuating in phase with model motion, and little overshoot from the static values. The pressures for the large amplitude motion showed large overshoots from the static values. In addition, during the high angle-of-attack portion of the motion, the upstroke (angle of attack increasing) pressure coefficients were typically much lower than the downstroke values. For the lower pitch rate, there was little difference between upstroke and downstroke pressures at the low angles of attack.

Thompson, S. A.; Batill, S. M.; Nelson, R. C.

1990-01-01

421

Effect of high hydrostatic pressures on 20S proteasome activity.  

PubMed

The 20S proteasome is the catalytic core of the ubiquitin proteolytic pathway, which is implicated in many cellular processes. The cylindrical structure of this complex consists of four stacked rings of seven subunits each. The central cavity is formed by two beta catalytic subunit rings in which protein substrates are progressively degraded. The 20S proteasome is isolated in a latent form which can be activated in vitro by various chemical and physical treatments. In this study, the effects of high hydrostatic pressures on 20S proteasome enzymatic activity were investigated. When proteasomes were subjected to increasing hydrostatic pressures, a progressive loss of peptidase activities was observed between 75 and 150 MPa. The inactivation also occurred when proteasomes were pressurized in the presence of synthetic peptide substrates; this may be the result of the dissociation of the 20S particle into its subunits under pressure, as was shown by PAGE. Pressurized proteasomes also lost their caseinolytic activity. In contrast, in the presence of casein, the pressure-induced inactivation and the dissociation of the 20S particles were prevented. In addition, in comparison to that observed at atmospheric pressure, their caseinolytic activity was increased under pressure. Following depressurization, the caseinolytic activity returned to basal levels but was further enhanced following an additional pressurization treatment. Thus, the structure of the 20S particle exhibits a certain degree of plasticity. This pressure-induced activation of the 20S proteasome is discussed in relation to its hollow structure, its currently accepted proteolytic mechanism and the general effect of high pressures on the biochemical reactions and structures of biopolymers. PMID:10411654

Gardrat, F; Fraigneau, B; Montel, V; Raymond, J; Azanza, J L

1999-06-01

422

High Rate Plasticity under Pressure using a Windowed Pressure-Shear Impact Experiment  

SciTech Connect

An experimental technique has been developed to study the strength of materials under conditions of moderate pressures and high shear strain rates. The technique is similar to the traditional pressure-shear plate-impact experiments except that window interferometry is used to measure both the normal and transverse particle velocities at a sample-window interface. Experimental and simulation results on vanadium samples backed with a sapphire window show the utility of the technique to measure the flow strength under dynamic loading conditions. The results show that the strength of the vanadium is 600 MPa at a pressure of 4.5 GPa and a plastic strain of 1.7%.

Florando, J N; Jiao, T; Grunschel, S E; Clifton, R J; Ferranti, L; Becker, R C; Minich, R W; Bazan, G

2009-07-29

423

High-pressure trickle-bed reactors: A review  

SciTech Connect

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

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

1997-08-01

424

Confinement of hydrogen at high pressure in carbon nanotubes  

DOEpatents

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)

2011-12-13

425

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

Microsoft Academic Search

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

Artem R. Oganov

426

Familial risk of high blood pressure in the Canadian population.  

PubMed

Familial risk ratios for high blood pressure were estimated in a representative sample of the Canadian population. The sample consisted of 14,069 participants 7-69 years of age from 5,753 families participating in the 1981 Canada Fitness Survey. Resting systolic (SBP) and diastolic (DBP) blood pressures were adjusted for the effects of body mass index using regression procedures. Varying degrees of high blood pressure were defined as the 75(th), 85(th), and 95(th) percentiles of age- and sex-specific values. Age- and sex-standardized risk ratios (SRRs) were calculated comparing the prevalences in the general population to those in spouses and first-degree relatives of probands with high blood pressure. SRRs for the 95(th) percentile were, for SBP and DBP, respectively, 1.37 and 1.45 in spouses and 1.33 and 2.36 in first-degree relatives of probands. SRRs decrease with decreasing percentile cut-offs used to define high blood pressure (95(th) > 85(th) > 75(th)), and SRRs are generally higher in first-degree relatives than in spouses, particularly for DBP. The results indicate significant familial risk for high blood pressure in the Canadian population, and the pattern of SRRs suggests that genetic factors may be responsible for a portion of the risk. PMID:11505470

Katzmarzyk, P T; Rankinen, T; Pérusse, L; Rao, D C; Bouchard, C

2001-01-01

427

High-pressure cooling of protein crystals without cryoprotectants.  

PubMed

Flash-cooling of protein crystals is the best known method to effectively mitigate radiation damage in macromolecular crystallography. To prevent physical damage to crystals upon cooling, suitable cryoprotectants must usually be found, a process that is time-consuming and in some cases unsuccessful. A method is described to cool protein crystals in high-pressure helium gas without the need for penetrative cryoprotectants. The method involves mounting protein crystals from the native mother liquor in a cryoloop with a droplet of oil, pressurizing the crystal to 200 MPa in He gas, cooling the crystal under pressure and then releasing the pressure. The crystal is then removed from the apparatus under liquid nitrogen and handled thereafter like a normal cryocooled crystal. Results are presented from three representative proteins. Dramatic improvement in diffraction quality in terms of resolution and mosaicity was observed in all cases. A mechanism for the pressure cooling is proposed involving high-density amorphous (HDA) ice which is produced at high pressure and is metastable at room pressure and 110 K. PMID:15983410

Kim, Chae Un; Kapfer, Raphael; Gruner, Sol M

2005-07-01

428

High-pressure intrapleural chemotherapy: feasibility in the pig model  

PubMed Central

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

2012-01-01

429

Evaluation of films for packaging applications in high pressure processing  

NASA Astrophysics Data System (ADS)

Food treatments implying high pressures used pre-packaging systems; consequently it appeared necessary to validate different packaging films able to be used in such processes. Two different packaging films from AMCOR FLEXIBLES have been evaluated: VIROFLEXAL: BOLSA 80 MICRAS, coextrusion PA/PE (20/60?m) RILTHENE: SEMI 20/60 MICRAS, laminate PA/PE (20/60?m) Three different physico-chemical characterizations have been developed for the evaluation of films behaviour after High Hydrostatic Pressure (HHP): (i) Mechanical properties (tensile strength and sealing strength), (ii) Oxygen permeability, (iii) Migration, through the contact with four food simulating liquids FSLs (water, acetic acid 3%, ethyl alcohol 10%, iso-octane). Two different pressures values (P = 400MPa and 500MPa) have been tested, with a duration of 15 min, at ambient temperature (+20°C) and only one pressure (P = 200MPa) for the experiments at low temperature (T = -20°C) with the same duration (15min). The selection of such values can be justified taking into account that experimental conditions as a temperature close to +20°C and a pressure between 400 and 500MPa are appropriated to inactivate bacteria and different others micro-organisms. Due to the efficiency of the association of hydrostatic pressure processing and low temperature (HHP/LT) [1, 2], the same films have been tested under high pressure processing (200MPa) but at negative temperature (-20°C).

Largeteau, A.; Angulo, I.; Coulet, J. P.; Demazeau, G.

2010-03-01

430

Pressure Relief Devices for High-Pressure Gaseous Storage Systems: Applicability to Hydrogen Technology  

SciTech Connect

Pressure relief devices (PRDs) are viewed as essential safety measures for high-pressure gas storage and distribution systems. These devices are used to prevent the over-pressurization of gas storage vessels and distribution equipment, except in the application of certain toxic gases. PRDs play a critical role in the implementation of most high-pressure gas storage systems and anyone working with these devices should understand their function so they can be designed, installed, and maintained properly to prevent any potentially dangerous or fatal incidents. As such, the intention of this report is to introduce the reader to the function of the common types of PRDs currently used in industry. Since high-pressure hydrogen gas storage systems are being developed to support the growing hydrogen energy infrastructure, several recent failure incidents, specifically involving hydrogen, will be examined to demonstrate the results and possible mechanisms of a device failure. The applicable codes and standards, developed to minimize the risk of failure for PRDs, will also be reviewed. Finally, because PRDs are a critical component for the development of a successful hydrogen energy infrastructure, important considerations for pressure relief devices applied in a hydrogen gas environment will be explored.

Kostival, A.; Rivkin, C.; Buttner, W.; Burgess, R.

2013-11-01

431

Advanced High-Temperature, High-Pressure Transport Reactor Gasification  

SciTech Connect

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

2005-08-30

432

Causes of high pressure compressor deterioration in service  

NASA Technical Reports Server (NTRS)

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

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

1979-01-01

433

Behavior of silver molybdate at high-pressure  

SciTech Connect

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)

2012-12-15

434

A high-pressure carbon dioxide gasdynamic laser  

NASA Technical Reports Server (NTRS)

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

Kuehn, D. M.

1973-01-01

435

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

DOEpatents

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

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

1997-01-01

436

Determination of the partial pressure of thallium in high-pressure lamp arcs: A comparative study  

SciTech Connect

The partial pressure of thallium in high-pressure Hg-TlI discharges with different mercury, thallium, and electron pressures has been measured by using the optically thin line Tl 655 nm and the self-reversed line Tl 535 nm. The partial pressure of the arc axis has been measured from the line Tl 655nm. The effective partial pressure has been measured from the self-reversed line Tl 535 nm on the basis of the multiparameter method, and it has been calculated from the known axis pressure of thallium and the calculation of its radial variation by taking into account the chemical reactions. The experimental results confirm the dispersion character of the blue wing of the line Tl 535 nm. The systematic difference obtained between the measured and calculated effective pressure, particularly at the moment of minimum electron density, may be interpreted by deviations from the local thermodynamic equilibrium (LTE) caused by overpopulation of the upper level of the line Tl 535 nm.

Karabourniotis, D.; Couris, S.; Damelincourt, J.J.; Aubes, M.

1986-08-01

437

Microscopic Analysis of Bacterial Motility at High Pressure  

PubMed Central

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

Nishiyama, Masayoshi; Sowa, Yoshiyuki

2012-01-01

438

High-pressure polymorphism of acetylsalicylic acid (aspirin): Raman spectroscopy  

NASA Astrophysics Data System (ADS)

Micro-Raman spectroscopy was used to elucidate the high-pressure polymorphic behavior of acetylsalicylic acid (ASA), an important pharmaceutical compound known as aspirin. Using a diamond anvil cell (DAC), single crystals of the two polymorphic phases of aspirin existing at ambient conditions (ASA-I and ASA-II) were compressed to 10 GPa. We found that ASA-I does not transform to ASA-II, but instead transforms to a new phase (ASA-III) above ?2 GPa. It is demonstrated that this transformation primarily introduces structural changes in the bonding and arrangement of the acetyl groups and is reversible upon the release of pressure. In contrast, a less dense ASA-II shows no transition in the pressure range studied, though it appears to exhibit a disordered structure above 7 GPa. Our results suggest that ASA-III is the most stable polymorph of aspirin at high pressures.

Crowell, Ethan L.; Dreger, Zbigniew A.; Gupta, Yogendra M.

2015-02-01

439

High pressure far infrared spectroscopy of ionic solids  

NASA Technical Reports Server (NTRS)

A high-pressure far-infrared cell operating at up to truly hydrostatic pressures of 8 kbar is described and used to determine the anharmonic self-energies associated with the transverse optic modes of ionic solids in which q approximately equals zero. The cell allows far-infrared studies in the spectral range below 120 reciprocal cm. The transverse optic modes were investigated to determine their mode Gruneisen constants and the pressure dependence of their inverse lifetimes in RbI, CsI, and TlCl.

Lowndes, R. P.

1974-01-01

440

The Melting Line of Molecular Hydrogen at High Pressure  

NASA Astrophysics Data System (ADS)

We have measured the melting line of molecular hydrogen to pressure P=82 GPa in a diamond anvil cell (DAC) using pulsed laser heating and found a peak at P=64.5±4 GPa and T=1055±20 K. Previous attempts to measure the melting temperature of hydrogen in a DAC by CW ohmic heating methods were limited by the diffusion of hydrogen at elevated temperatures. We have developed a technique of temperature determination in a pulsed laser heated DAC and succeeded to achieve much higher pressures and temperatures. In the pulsed laser method hydrogen diffusion is suppressed allowing access to high temperatures at elevated pressures.

Deemyad, Shanti; Silvera, Isaac

2008-03-01

441

Structural Behaviour of Uranium Sulfide under High Pressure  

SciTech Connect

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

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

2011-07-15

442

A Study of the Ion Hose Instability in the DARHT-II Downstream Transport Region  

SciTech Connect

The second axis of the DARHT flash X-ray facility at Los Alamos National Laboratory (''DARHT-II'') is a multiple-pulse, 18.4 MeV, 2 kA induction electron linear accelerator [1]. A train of short ({approx}50 ns) pulses are converted via bremsstrahlung to X-rays, which are then used to make radiographic images at various times (nominally four) during a ''hydrotest'' experiment. The train of pulses is created by carving them out of a two microsecond long macropulse, using a fast switching element called a kicker [2]. The unused portion of the macropulse is absorbed in a beam dump. Thus, upstream of the kicker, two microseconds of beam are transported through a vacuum system roughly sixty meters long. These conditions involve length and, specifically, time scales which are new to the transport of high-current beams. A concern under such conditions are the macroscopic interactions between the electron beam and positive ions created by impact ionization of the residual gas in the vacuum system. Over two microseconds, the ion density can develop to a hundredth or even a tenth of a percent of the beam density--small, to be sure, but large enough to have cumulative effects over such a long transport distance. Two such effects will be considered here: the ion hose instability, where transverse forces conspire to pull the electron beam farther and farther off axis, and background gas focusing, where radial forces (with respect to the beam) change the beam envelope during the course of the macropulse. The former effect can cause beam emittance growth (affecting the ability to focus the beam on the target) and eventually catastrophic beam loss; the latter can cause either serious degradation of the statically tuned final focus on the converter target, or a pinching of the beam on the surface of the main dump to the point where the heat flux causes damage. The beam transport upstream of the kicker has two distinct phases. First, the beam is created and accelerated up to 18.4 MeV over a distance of about fifty meters. Then the true downstream transport begins: the beam drifts through a matching section in preparation for the kicker, over some ten meters; the long-pulse beam then travels about four more meters from the kicker to the main dump. In the accelerator, the beam energy is obviously not constant; the transport is emittance-dominated and done through nearly continuous solenoidal focusing. In the downstream section, there are only two discrete solenoids over the entire fourteen meters and the transport is largely ballistic. Since ion hose has been studied in the accelerator [3] and since the lack of continuous focusing is considered a concern with respect to ion hose in the downstream section, the focus of this study is only from the exit of the accelerator to the main dump. A more in-depth description of the baseline (ion-free) DARHT-II downstream transport, including description of the actual transport elements and their use, will not be presented in this document; such details can be found in the documents cited in the References. The study of these effects will be done in stages. In the next section, the nature of the residual gas in the vacuum system will be considered, along with the various assumptions made in characterizing the creation of ions. Then the ion hose instability will be described in its simplest form. In the fourth section, additional features of ion hose will then be presented which attempt to capture some of the key behavior. Then a much more complete model using particle-in-cell (PIC) numerical techniques will be described, followed by details of the specific implementation used here. In section seven, the code will be benchmarked against results published in the literature. Section eight has the most relevant material: the actual study of the effects of ion hose and background gas focusing in the DARHT-II downstream transport region. In section nine, a simple experiment which can be tacked on to existing experiments is proposed in order to verify the modeling. Finally, the results are summarized and the v

McCarrick, J F

2004-11-11

443

Nanocrystalline Cu 2 O prepared under high pressures  

Microsoft Academic Search

The effect of high pressure on the structure of Cu2O is investigated. Polycrystalline samples are treated during different periods of time at different temperatures and pressures\\u000a in the vicinity of the kinetic curve of the decomposition Cu2O ? Cu+CuO. The structure of the samples subjected to thermobaric treatment is characterized by x-ray diffraction, electron\\u000a diffraction structural analysis, and electron microscopy

E. G. Ponyatovskii; G. E. Abrosimova; A. S. Aronin; V. I. Kulakov; I. V. Kuleshov; V. V. Sinitsyn

2002-01-01

444

High pressure far infrared spectroscopy of ionic solids  

Microsoft Academic Search

A high-pressure far-infrared cell operating at up to truly hydrostatic pressures of 8 kbar is described and used to determine the anharmonic self-energies associated with the transverse optic modes of ionic solids in which q approximately equals zero. The cell allows far-infrared studies in the spectral range below 120 reciprocal cm. The transverse optic modes were investigated to determine their

R. P. Lowndes

1974-01-01

445

Nonenzymatic modifications of proteins under high-pressure treatment  

Microsoft Academic Search

High-pressure treatment, e.g. used as an alternative method for food preservation, affects protein cross-linking and glycation reactions. These reactions were monitored by using mainly milk proteins in the absence and presence of different saccharides or dicarbonyl compounds. Without carbohydrates, protein cross-linking of casein is enhanced by pressure through the formation of dehydroalanine-derived lysinoalanine. A similar effect can be observed in

Uwe Schwarzenbolz; Thomas Henle

2010-01-01

446

Phase transition of La- chalcogenides under high pressure  

SciTech Connect

The lanthanum compounds have been found to undergo transition from their initial NaCl-type structure to high pressure body centered tetragonal (BCT) structure (distorted CsCl-type P4/mmm) using CTIP model. The calculated values of cohesive energy, lattice constant, phase transition pressure, relative volume collapse agree well with the available measured data and better than those computed by earlier workers.

Gupta, Dinesh Chandra [Condensed Matter Theory Group, School of Studies in Physics, Jiwaji University, Gwalior - 474 011 (India); Raypuria, Gajendra Singh, E-mail: gsraypuria@gmail.com [Department of Physics, Govt. K.R.G. P.G. Autonomous College, Gwalior - 474 001 (India)

2014-04-24

447

Modelling and Analysis of High Pressure Peaking Switch  

NASA Astrophysics Data System (ADS)

This paper presents modelling and analysis of peaking switch used in Marx generator, such that the rise time of the pulse produced by the Marx generator is reduced substantially. Towards this FEMM (Finite Element Methods Magnetics) software is used for the field modelling of the switch and MATLAB for circuit modelling to observe the rise time. The switch has to produce pulse with sub-nanosecond rise time, hence the electrode distance has to be minimum. This switch can withstand high voltage only under high pressure. A mathematical model is simulated in MATLAB to see the performance under high pressure.

S, Bindu; Parekh, Mrunal; Mangalvedekar, H. A.; Sharma, Archana; Chakravarthy, D. P.

2012-07-01

448

A System for Incubations at High Gas Partial Pressure  

PubMed Central

High-pressure is a key feature of deep subsurface environments. High partial pressure of dissolved gasses plays an important role in microbial metabolism, because thermodynamic feasibility of many reactions depends on the concentration of reactants. For gases, this is controlled by their partial pressure, which can exceed 1?MPa at in situ conditions. Therefore, high hydrostatic pressure alone is not sufficient to recreate true deep subsurface in situ conditions, but the partial pressure of dissolved gasses has to be controlled as well. We developed an incubation system that allows for incubations at hydrostatic pressure up to 60?MPa, temperatures up to 120°C, and at high gas partial pressure. The composition and partial pressure of gasses can be manipulated during the experiment. To keep costs low, the system is mainly made from off-the-shelf components with only very few custom-made parts. A flexible and inert PVDF (polyvinylidene fluoride) incubator sleeve, which is almost impermeable for gases, holds the sample and separates it from the pressure fluid. The flexibility of the incubator sleeve allows for sub-sampling of the medium without loss of pressure. Experiments can be run in both static and flow-through mode. The incubation system described here is usable for versatile purposes, not only the incubation of microorganisms and determination of growth rates, but also for chemical degradation or extraction experiments under high gas saturation, e.g., fluid–gas–rock-interactions in relation to carbon dioxide sequestration. As an application of the system we extracted organic compounds from sub-bituminous coal using H2O as well as a H2O–CO2 mixture at elevated temperature (90°C) and pressure (5?MPa). Subsamples were taken at different time points during the incubation and analyzed by ion chromatography. Furthermore we demonstrated the applicability of the system for studies of microbial activity, using samples from the Isis mud volcano. We could detect an increase in sulfate reduction rate upon the addition of methane to the sample. PMID:22347218

Sauer, Patrick; Glombitza, Clemens; Kallmeyer, Jens

2012-01-01

449

Reinvestigation of high pressure polymorphism in hafnium metal  

SciTech Connect

There has been a recent controversy about the high pressure polymorphism of Hafnium (Hf). Unlike, the earlier known ??? structural transition at 38?±?8?GPa, at ambient temperature, Hrubiak et al. [J. Appl. Phys. 111, 112612 (2012)] did not observe it till 51?GPa. They observed this transition only at elevated temperatures. We have reinvestigated the room temperature phase diagram of Hf, employing x-ray diffraction (XRD) and DFT based first principles calculations. Experimental investigations have been carried out on several pure and impure Hf samples and also with different pressure transmitting media. Besides demonstrating the significant role of impurity levels on the high pressure phase diagram of Hf, our studies re-establish room temperature ??? transition at high pressures, even in quasi-hydrostatic environment. We observed this transition in pure Hf with equilibrium transition pressure P{sub o}?=?44.5?GPa; however, with large hysteresis. The structural sequence, transition pressures, the lattice parameters, the c/a ratio and its variation with compression for the ? and ? phases as predicted by our ab-initio scalar relativistic (SR) calculations are found to be in good agreement with our experimental results of pure Hf.

Pandey, K. K., E-mail: kkpandey@barc.gov.in; Sharma, Surinder M. [High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai-400 085 (India); Gyanchandani, Jyoti; Dey, G. K. [Materials Science Division, Bhabha Atomic Research Centre, Mumbai-400 085 (India); Somayazulu, M. [Geophysical Laboratory, Carnegie Institution of Washington, Washington, D.C. 20015 (United States); Sikka, S. K. [Indian National Science Academy, New Delhi-110 002 (India)

2014-06-21

450

PARTICULATE CONTROL HIGHLIGHTS: RESEARCH AT HIGH TEMPERATURE/PRESSURE  

EPA Science Inventory

The report gives highlights of EPA high-temperature and high-pressure programs aimed at demonstrating control technology to meet environmental standards for the ambient concentration of particles and the emission rate of particles from new sources. Among the control devices consi...

451

Heart and Artery Damage and High Blood Pressure  

MedlinePLUS

Heart and Artery Damage and High Blood Pressure Updated:Sep 11,2014 There are several harmful consequences for your arteries and heart because high blood ... flow to tissue on the other side. Damaged arteries cause blood supply failures. When a blockage cuts off the ...

452

Nanotubes in boron nitride laser heated at high pressure  

Microsoft Academic Search

Here we report on the finding of pure boron nitride (BN) nanotubes that do not contain any additional inclusions and on a new method for their growth: laser heating of boron nitrides at high nitrogen pressure (5–15 GPa). The multiwalled nanotubes were observed using high resolution electron microscopy and were chemically characterized by electron energy loss spectroscopy. The circular or

D. Golberg; Y. Bando; M. Eremets; K. Takemura; K. Kurashima; H. Yusa

1996-01-01

453

Spontaneous Raman Scattering Diagnostics for High-pressure Gaseous Flames  

NASA Technical Reports Server (NTRS)

A high-pressure (up to 60 atm) gaseous burner facility with optical access that provides steady, reproducible flames with high precision, and the ability to use multiple fuel/oxidizer combinations has been developed. In addition, a high-performance spontaneous Raman scattering system for use in the above facility has also been developed. Together, the two systems will be used to acquire and establish a comprehensive Raman scattering spectral database for use as a quantitative high-pressure calibration of single-shot Raman scattering measurements in high-pressure combustion systems. Using these facilities, the Raman spectra of H2-Air flames were successfully measured at pressures up to 20 atm. The spectra demonstrated clear rotational and ro-vibrational Raman features of H2, N2, and H2O. theoretical Raman spectra of pure rotational H2, vibrational H2, and vibrational N2 were calculated using a classical harmonic-oscillator model with pressure broadening effects and fitted to the data. At a gas temperature of 1889 K for a phi = 1.34 H2-Air flame, the model and the data showed good agreement, confirming a ro-vibrational equilibrium temperature.

Kojima, Jun; Nguyen, Quang-Viet; Reddy, D. R. (Technical Monitor)

2002-01-01

454

An experimental investigation of high temperature, high pressure paper drying  

E-print Network

function of number of drying passes for drying temperatures of 149 and 204 'C (300 and 400 F), contact pressures of 1. 4 and 2. 1 MPa (200 and 300 psi), a basis weight of 100 g/m' (0. 021 lb/ft'), and contact times of 20, 40, and 60 msec with same side... QI I- IJI N QI I- l1. V o c 0 3. 0 2. 5 2. 0 1, 5 1. 0 0. 5 0, 0 basis weight = 25 g/m~ contact pressure = 1. 40 x screw position + 1. 63 ? 0. 7 -0. 5 ? 0. 3 ? 0, 1 0. 1 0. 3 Sc rew Position (revolutions) Fi . 3 Calibration...

Patel, Kamal Raoji

1994-01-01

455

Advanced Synchrotron Techniques at High Pressure Collaborative Access Team (HPCAT)  

NASA Astrophysics Data System (ADS)

High Pressure Collaborative Access Team (HPCAT) is dedicated to advancing cutting-edge, multidisciplinary, high-pressure science and technology using synchrotron radiation at Sector 16 of the Advanced Photon Source (APS) of Argonne National Laboratory. At HPCAT an array of novel x-ray diffraction and spectroscopic techniques has been integrated with high pressure and extreme temperature instrumentation for studies of structure and materials properties at extreme conditions.. HPCAT consists of four active independent beamlines performing a large range of various experiments at extreme conditions. 16BM-B beamline is dedicated to energy dispersive and white Laue X-ray diffraction. The majority of experiments are performed with a Paris-Edinburgh large volume press (to 7GPa and 2500K) and include amorphous and liquid structure measurement, white beam radiography, elastic sound wave velocity measurement of amorphous solid materials, with viscosity and density measurement of liquid being under development. 16BM-D is a monochromatic diffraction beamline for powder and single crystal diffraction at high pressure and high (resistive heating) / low (cryostats) temperature. The additional capabilities include high-resolution powder diffraction and x-ray absorption near edge structure (XANES) spectroscopy. The insertion device beamline of HPCAT has two undulators in canted mode (operating independently) and LN cooled Si monochromators capable of providing a large range of energies. 16IDB is a microdiffraction beamline mainly focusing on high-pressure powder and single crystal diffraction in DAC at high temperatures (double-sided laser heating and resistive heating) and low temperature (various cryostats). The modern instrumentation allows high-quality diffraction at megabar pressures from light element, fast experiments with pulsed laser heating, fast dynamic experiments with Pilatus detector, and so on. 16ID-D beamline is dedicated to x-ray scattering and spectroscopy research of materials under high pressure in DAC. The available techniques include nuclear forward scattering, nuclear resonant inelastic scattering with 2meV energy resolution for determining phonon density of state and Mössbauer effect, x-ray inelastic scattering (X-ray Raman) with 1eV energy resolution for the study of charge dynamics and chemical bonding, x-ray spectroscopy for the study of electronic excitations, X-ray emission (including partial fluorescence yield, resonant emission). Many of these measurements can be done at low temperature, with in-situ pressure measurement, or at high temperature with portable laser heating. All these advanced synchrotron techniques, as well as supporting facilities, employed at HPCAT, will be discussed.

Shen, G.; Sinogeikin, S. V.; Chow, P.; Kono, Y.; Meng, Y.; Park, C.; Popov, D.; Rod, E.; Smith, J.; Xiao, Y.; Mao, H.

2012-12-01

456

HIGH TEMPERATURE HIGH PRESSURE THERMODYNAMIC MEASUREMENTS FOR COAL MODEL COMPOUNDS  

SciTech Connect

The enthalpy of a fluid measured with respect to some reference temperature and pressure (enthalpy increment or Cp) is required for many engineering designs. Different techniques for determining enthalpy increments include direct measurement, integration of heat capacity as a function of temperature at constant pressure, and calculation from accurate density measurements as a function of temperature and pressure with ideal-gas enthalpies. Techniques have been developed for measurement of heat capacities using differential scanning calorimeters, but routine measurements with a precision better than 3% are rare. For thermodynamic model development, excess enthalpies or enthalpies of mixing of binary and ternary systems are generally required. Although these data can be calculated from measured values of incremental enthalpies of mixtures and corresponding pure components, the method of calculation involves subtraction of large numbers, and it is impossible to obtain accurate results from relatively accurate incremental enthalpy data. Directly measured heats of mixing provide better data for model development. In what follows, we give a brief literature survey of experimental methods available for measurement of incremental enthalpies as well as heats of mixing.

Vinayak N. Kabadi

1999-02-24

457

A novel high pressure, high temperature vessel used to conduct long-term stability measurements of silicon MEMS pressure transducers  

NASA Astrophysics Data System (ADS)

The need to quantify and to improve long-term stability of pressure transducers is a persistent requirement from the aerospace sector. Specifically, the incorporation of real-time pressure monitoring in aircraft landing gear, as exemplified in Tire Pressure Monitoring Systems (TPMS), has placed greater demand on the pressure transducer for improved performance and increased reliability which is manifested in low lifecycle cost and minimal maintenance downtime through fuel savings and increased life of the tire. Piezoresistive (PR) silicon MEMS pressure transducers are the primary choice as a transduction method for this measurement owing to their ability to be designed for the harsh environment seen in aircraft landing gear. However, these pressure transducers are only as valuable as the long-term stability they possess to ensure reliable, real-time monitoring over tens of years. The "heart" of the pressure transducer is the silicon MEMS element, and it is at this basic level where the long-term stability is established and needs to be quantified. A novel High Pressure, High Temperature (HPHT) vessel has been designed and constructed to facilitate this critical measurement of the silicon MEMS element directly through a process of mechanically "floating" the silicon MEMS element while being subjected to the extreme environments of pressure and temperature, simultaneously. Furthermore, the HPHT vessel is scalable to permit up to fifty specimens to be tested at one time to provide a statistically significant data population on which to draw reasonable conclusions on long-term stability. With the knowledge gained on the silicon MEMS element, higher level assembly to the pressure transducer envelope package can also be quantified as to the build-effects contribution to long-term stability in the same HPHT vessel due to its accommodating size. Accordingly, a HPHT vessel offering multiple levels of configurability and robustness in data measurement is presented, along with 10 year long-term stability results.

Wisniewiski, David

2014-03-01

458

46 CFR 76.10-10 - Fire station hydrants, hose and nozzles.  

Code of Federal Regulations, 2014 CFR

...Shipping 3 2014-10-01 2014-10-01 false Fire station hydrants, hose and nozzles. 76.10-10...HOMELAND SECURITY (CONTINUED) PASSENGER VESSELS FIRE PROTECTION EQUIPMENT Fire Main System, Details § 76.10-10 Fire...

2014-10-01

459

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

SciTech Connect

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

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

1999-10-07

460

Real-life Stories About High Blood Pressure | NIH MedlinePlus the Magazine  

MedlinePLUS

... turn Javascript on. Feature: High Blood Pressure Real-life Stories About High Blood Pressure Past Issues / Fall ... who’s getting back in control!” For more real-life stories about high blood pressure, visit www.nhlbi. ...

461

76 FR 59658 - High Pressure Steel Cylinders From the People's Republic of China: Postponement of Preliminary...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Administration [A-570-977] High Pressure Steel Cylinders From the People's Republic...antidumping duty investigation on high pressure steel cylinders from the People's Republic...1\\ See High Pressure Steel Cylinders from the People's...

2011-09-27

462

77 FR 1060 - High Pressure Steel Cylinders From the People's Republic of China: Postponement of Final...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Administration [A-570-977] High Pressure Steel Cylinders From the People's Republic...antidumping duty investigation on high pressure steel cylinders from the People's Republic...1\\ See High Pressure Steel Cylinders from the People's...

2012-01-09

463

78 FR 55059 - High Pressure Steel Cylinders from the People's Republic of China: Rescission of Countervailing...  

Federal Register 2010, 2011, 2012, 2013, 2014

...Administration [C-570-978] High Pressure Steel Cylinders from the People's Republic...the countervailing duty order on high pressure steel cylinders (cylinders) from the...the Countervailing Duty Order on High Pressure Steel Cylinders from the People's...

2013-09-09

464

Pressure and Temperature effects on the High Pressure Phase Transformation in Zirconium  

SciTech Connect

At high pressure zirconium is known to undergo a phase transformation from the hexagonal close packed (HCP) alpha phase ({alpha}) to the simple hexagonal omega phase ({omega}). Under conditions of shock loading, the high-pressure omega phase is retained upon release. However, the hysteresis in this transformation is not well represented by equilibrium phase diagrams. For this reason, the influence of peak shock pressure and temperature on the retention of omega phase in Zr is explored in this study. In situ VISAR measurements along with post-mortem metallographic and neutron diffraction characterization of soft recovered specimens have been utilized to quantify the volume fraction of retained omega phase, morphology of the shocked alpha and omega phases, and qualitatively understand the kinetics of this transformation. This understanding of the role of peak shock stress will be utilized to address physics to be encoded in our present macro-scale models.

Escobedo-Diaz, Juan P. [Los Alamos National Laboratory; Cerreta, Ellen K. [Los Alamos National Laboratory; Brown, Donald W. [Los Alamos National Laboratory; Trujillo, Carl P. [Los Alamos National Laboratory; Rigg, Paulo A. [Los Alamos National Laboratory; Bronkhorst, Curt A. [Los Alamos National Laboratory; Addessio, Francis L. [Los Alamos National Laboratory; Lookman, Turab [Los Alamos National Laboratory

2012-06-20

465

Unsteady pressure loads in a generic high speed engine model  

NASA Technical Reports Server (NTRS)

Unsteady pressure loads were measured along the top interior wall of a generic high-speed engine (GHSE) model undergoing performance tests in the combustion-Heated Scramjet Test Facility at the Langley Research Center. Flow to the model inlet was simulated at 72000 ft and a flight Mach number of 4. The inlet Mach number was 3.5 with a total temperature and pressure of 1640 R and 92 psia. The unsteady pressure loads were measured with 5 piezoresistive gages, recessed into the wall 4 to 12 gage diameters to reduce incident heat flux to the diaphragms, and distributed from the inlet to the combustor. Contributors to the unsteady pressure loads included boundary layer turbulence, combustion noise, and transients generated by unstart loads. Typical turbulent boundary layer rms pressures in the inlet ranged from 133 dB in the inlet to 181 dB in the combustor over the frequency range from 0 to 5 kHz. Downstream of the inlet exist, combustion noise was shown to dominate boundary layer turbulence noise at increased heat release rates. Noise levels in the isolator section increased by 15 dB when the fuel-air ratio was increased from 0.37 to 0.57 of the stoichiometric ratio. Transient pressure disturbances associated with engine unstarts were measured in the inlet and have an upstream propagation speed of about 7 ft/sec and pressure jumps of at least 3 psia.

Parrott, Tony L.; Jones, Michael G.; Thurlow, Ernie M.

1992-01-01

466

Ultra-high pressure water jet: Baseline report  

SciTech Connect

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

1997-07-31

467

Achieving unusual oxidation state of matter under high pressure  

NASA Astrophysics Data System (ADS)

Pressure has many effects to matter including the reduction of the volume, the increase of the coordination number and the broadening of the band-widths. In the past, most of the high-pressure studies focused on structural and electronic state phase transitions. Using first principles calculations and a bias-free structural search method, we will demonstrate that high pressure can lead to high oxidation state of elements that can never be achieved under ambient condition, making high pressure technique a nice tool to explore many traditional topics in solid state and molecular chemistry. As an example, we will show that Hg can transfer the electrons in its outmost d shell to F atoms and form HgF4 molecular crystals under pressure, thereby acting as a true transition metal. Group IIB elements, including Zn, Cd, and Hg are usually defined as post-transition metals because they are commonly oxidized only to the +2 state. Their d shells are completely filled and do not participate in the formation of chemical bonds. Although the synthesis of HgF4 molecules in gas phase was reported before, the molecules show strong instabilities and dissociate. Therefore, the transition metal propensity of Hg remains an open question.

Wang, Xiaoli; Lin, Haiqing; Ma, Yanming; Miao, Maosheng

2013-03-01

468

A high pressure modulated molecular beam mass spectrometric sampling system  

NASA Technical Reports Server (NTRS)

The current state of understanding of free-jet high pressure sampling is critically reviewed and modifications of certain theoretical and empirical considerations are presented. A high pressure, free-jet expansion, modulated molecular beam, mass spectrometric sampling apparatus was constructed and this apparatus is described in detail. Experimental studies have demonstrated that the apparatus can be used to sample high temperature systems at pressures up to one atmosphere. Condensible high temperature gaseous species have been routinely sampled and the mass spectrometric detector has provided direct identification of sampled species. System sensitivity is better than one tenth of a part per million. Experimental results obtained with argon and nitrogen beams are presented and compared to theoretical predictions. These results and the respective comparison are taken to indicate acceptable performance of the sampling apparatus. Results are also given for two groups of experiments related to hot corrosion studies. The formation of gaseous sodium sulfate in doped methane-oxygen flames was characterized and the oxidative vaporization of metals was studied in an atmospheric pressure flowing gas system to which gaseous salt partial pressures were added.

Stearns, C. A.; Kohl, F. J.; Fryburg, G. C.; Miller, R. A.

1977-01-01

469

Ultra-high pressure water jet: Baseline report; Greenbook (chapter)  

SciTech Connect

The ultra-high pressure waterjet technology was being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The ultra-high pressure waterjet technology acts as a cutting tool for the removal of surface substrates. The Husky{trademark} pump feeds water to a lance that directs the high pressure water at the surface to be removed. The technologies being tested for concrete decontamination are targeted for alpha contamination. The safety and health evaluation during the human factors assessment focused on two main areas: noise and dust.

NONE

1997-07-31

470

High blood pressure, oxygen radicals and antioxidants: etiological relationships.  

PubMed

This hypothesis proposes that high blood pressure is a pathological state associated with a loss of the balance between pro-oxidation and antioxidation, energy depletion, and accelerated aging in the target organs, such as heart, kidney and brain. Different nutritional, environmental, pharmacological factors and/or associated pathologies (diabetes, arteriosclerosis, cancer, alcoholism, etc.) and/or genetic components, can induce high blood pressure by breaking the redox equilibrium in the affected organs. Additional evidence, such as increase of oxidative damage, fibrogenesis, inhibition of the cardiocytic sodium-potassium pump, and heart hypertrophy, supports this hypothesis. These facts are analysed in the present paper, showing that they could contribute to the development of high blood pressure and associated pathologies by oxidative mechanisms. PMID:8733174

Romero-Alvira, D; Roche, E

1996-04-01

471

A high-pressure bi-directional cycloid rotor flowmeter.  

PubMed

The measurement of the flow rate of various liquids and gases is critical in industrial automation. Rotary positive displacement meters (rotary PD meters) are highly accurate flowmeters that are widely employed in engineering applications, especially in custody transfer operations and hydraulic control systems. This paper presents a high pressure rotary PD meter containing a pair of internal cycloid rotors. It has the advantages of concise structure, low pressure loss, high accuracy and low noise. The curve of the internal rotor is designed as an equidistant curtate epicycloid curve with the external rotor curve as its conjugate. The calculation method used to determine the displacement of the cycloid rotor flowmeter is discussed. A prototype was fabricated, and experiments were performed to confirm measurements over a flow range of 1-100 L/min with relative errors of less than ±0.5%. The pressure loss through the flowmeter was about 3 bar at a flow rate of 100 L/min. PMID:25196162

Liu, Shuo; Ding, Fan; Ding, Chuan; Man, Zaipeng

2014-01-01

472

Structural investigation of amorphous materials at high pressures  

SciTech Connect

A modified diamond anvil cell (DAC) is used for structural studies of amorphous materials at high pressures using a monochromatic synchrotron x-ray beam. The DAC modification includes (1) the use of x-ray transparent seats for a large angular opening for x-ray scattering, and (2) the introduction of a boron gasket insert to increase the sample thickness and to minimize the gasket-hole deformation. A procedure for absorption correction and background subtraction in DAC experiments is described, together with an optimization process for obtaining accurate data of the structure factor and the corresponding pair distribution function. Data for amorphous iron at 67 GPa are presented for demonstration. It is shown that quantitative structural data can be determined for amorphous materials at very high pressures using the DAC. The apparatus should be also useful for structural studies of liquids at high pressures.

Shen, G.; Prakapenka, V.B.; Rivers, M.L.; Sutton, S.R. (UC)

2010-12-06

473

A High-Pressure Bi-Directional Cycloid Rotor Flowmeter  

PubMed Central

The measurement of the flow rate of various liquids and gases is critical in industrial automation. Rotary positive displacement meters (rotary PD meters) are highly accurate flowmeters that are widely employed in engineering applications, especially in custody transfer operations and hydraulic control systems. This paper presents a high pressure rotary PD meter containing a pair of internal cycloid rotors. It has the advantages of concise structure, low pressure loss, high accuracy and low noise. The curve of the internal rotor is designed as an equidistant curtate epicycloid curve with the external rotor curve as its conjugate. The calculation method used to determine the displacement of the cycloid rotor flowmeter is discussed. A prototype was fabricated, and experiments were performed to confirm measurements over a flow range of 1–100 L/min with relative errors of less than ±0.5%. The pressure loss through the flowmeter was about 3 bar at a flow rate of 100 L/min. PMID:25196162

Liu, Shuo; Ding, Fan; Ding, Chuan; Man, Zaipeng

2014-01-01

474

STS-46 crewmembers line up along hose during fire training at JSC  

NASA Technical Reports Server (NTRS)

STS-46 Atlantis, Orbiter Vehicle (OV) 104, crewmembers, lined up along a water hose, take a break after extinquishing a blaze in JSC's Fire Training Pit during fire fighting and fire training exercises. At the front of the line holding the hose nozzle is Commander Loren J. Shriver with Pilot Andrew M. Allen, backup Italian Payload Specialist Umberto Guidoni, and Italian Payload Specialist Franco Malerba behind him. The Fire Training Pit is located across from the Gilruth Center Bldg 207.

1992-01-01

475

High pressure electrides: a predictive chemical and physical theory.  

PubMed

Electrides, in which electrons occupy interstitial regions in the crystal and behave as anions, appear as new phases for many elements (and compounds) under high pressure. We propose a unified theory of high pressure electrides (HPEs) by treating electrons in the interstitial sites as filling the quantized orbitals of the interstitial space enclosed by the surrounding atom cores, generating what we call an interstitial quasi-atom, ISQ. With increasing pressure, the energies of the valence orbitals of atoms increase more significantly than the ISQ levels, due to repulsion, exclusion by the atom cores, effectively giving the valence electrons less room in which to move. At a high enough pressure, which depends on the element and its orbitals, the frontier atomic electron may become higher in energy than the ISQ, resulting in electron transfer to the interstitial space and the formation of an HPE. By using a He lattice model to compress (with minimal orbital interaction at moderate pressures between the surrounding He and the contained atoms or molecules) atoms and an interstitial space, we are able to semiquantitatively explain and predict the propensity of various elements to form HPEs. The slopes in energy of various orbitals with pressure (s > p > d) are essential for identifying trends across the entire Periodic Table. We predict that the elements forming HPEs under 500 GPa will be Li, Na (both already known to do so), Al, and, near the high end of this pressure range, Mg, Si, Tl, In, and Pb. Ferromagnetic electrides for the heavier alkali metals, suggested by Pickard and Needs, potentially compete with transformation to d-group metals. PMID:24702165

Miao, Mao-Sheng; Hoffmann, Roald

2014-04-15

476

Crystal growth rates of tricaprin and trilaurin under high pressures  

NASA Astrophysics Data System (ADS)

The effect of hydrostatic pressure on a linear crystal growth rate of tricaprin and trilaurin was investigated by the use of a capillary method in the pressure range up to 200 MPa. The undercooling temperature, ? T, was varied from 0.65 to 16 K. In order to investigate crystal growth kinetics of triacylglycerols, the melting temperature, density and viscosity were also measured under high pressures. The crystal growth rates of tricaprin and trilaurin decrease with increasing values of pressure applied. It was found that the crystal growth rate, v, can be expressed by the form v= A? Tn with n which can take large value in a range of small ? T value, whereas n decreases with increasing ? T value. From the comparison with several theories for the crystal growth from melts, the present result suggests that the two triacylglycerols freeze by the dislocation mechanism in the small ? T range and by the continuous mechanism in the large ? T range.

Yokoyama, Chiaki; Tamura, Yuichi; Nishiyama, Yoshiyuki

1998-08-01

477

Some observations in high pressure rheology of lubricants  

NASA Technical Reports Server (NTRS)

Experimental data are presented on viscosity, elastic shear modulus, and limiting shear stress of 12 liquid lubricants. It is shown that transition histories do affect the limiting shear stress of the materials in the form of isothermal compression resulting in a lower density and lower limiting stress than isobaric cooling. The measured limiting shear stress agrees with EHD traction data at slide-to-roll ratios of 0.1 or more. In pressure viscosity measurements of the polymer solutions, it is found that for some temperatures, the pressure viscosity coefficient of the blend is slightly less than that of the base, which results in the crossing of the viscosity-pressure isotherms at high pressures.

Bair, S.; Winer, W. O.

1981-01-01

478

LX-17 Deflagration at High Pressures and Temperatures  

SciTech Connect

We measure the laminar deflagration rate of LX-17 (92.5 wt% TATB, 7.5 wt% Kel-F 800) at high pressure and temperature in a strand burner, thereby obtaining reaction rate data for prediction of thermal explosion violence. Simultaneous measurements of flame front time-of-arrival and temporal pressure history allow for the direct calculation of deflagration rate as a function of pressure. Additionally, deflagrating surface areas are calculated in order to provide quantitative insight into the dynamic surface structure during deflagration and its relationship to explosion violence. Deflagration rate data show that LX-17 burns in a smooth fashion at ambient temperature and is represented by the burn rate equation B = 0.2P{sup 0.9}. At 225 C, deflagration is more rapid and erratic. Dynamic deflagrating surface area calculations show that ambient temperature LX-17 deflagrating surface areas remain near unity over the pressure range studied.

Koerner, J; Maienschein, J; Black, K; DeHaven, M; Wardell, J

2006-10-23

479

Relationship between structural variation and spin transition of iron under high pressures and high temperatures  

NASA Astrophysics Data System (ADS)

The high-pressure and high-temperature behavior of the spin state in hexagonal close-packed (hcp) Fe has been examined using synchrotron X-ray diffraction up to 180 GPa pressure and 2000 K temperature using the diamond anvil cell technique. The spin transition of the high-pressure Fe phase with the hcp structure from high to low state was confirmed. A significant change in the c/a ratio of the cell parameters of hcp-Fe was observed at the transition boundary. The spin transition pressure, P, increased as the temperature increased. The transition boundary was estimated to be P (GPa)=51+0.045×T (K).

Ono, Shigeaki

2015-02-01

480

Technical and economic evaluation of ten high temperature, high pressure particulate cleanup systems for pressurized fluidized bed combustion  

Microsoft Academic Search

The objective of this analysis was to provide a technical and economic evaluation of the ten high temperature, high pressure (HTHP) systems for the purpose of prioritizing them according to performance, cost, and general viability of achieving commercial status. The scope primarily included reviewing\\/normalizing test experience to date, normalizing commercial designs, developing normalized capital and operating costs for each system,

L. N. Rubow; M. Borden; T. L. Buchanan; J. A. C. Cramp; W. H. Fischer; M. G. Klett; S. M. Maruvada; E. T. Nelson; R. E. Weinstein; R. Zaharchuk

1984-01-01

481

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

SciTech Connect

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)

2013-01-28

482

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

NASA Astrophysics Data System (ADS)

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.

2013-01-01

483

Microhole High-Pressure Jet Drill for Coiled Tubing  

SciTech Connect

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

2007-06-30

484

High-pressure Raman spectroscopy of Re3N crystals  

NASA Astrophysics Data System (ADS)

Well-crystallized plate-like Re3N crystals were synthesized through a high-pressure solid-state metathesis (HPSSM) reaction in large volume press (LVP) at 14 GPa and 1973 K. The vibrational properties of Re3N crystals were studied by high-pressure Raman spectroscopy in diamond anvil cell (DAC) up to 20 GPa. The mode-Grüneisen parameters for Raman modes of Re3N were determined experimentally, which were found substantially being larger than previously calculated values.

Jiang, Xiaodong; Lei, Li; Hu, Qiwei; Feng, Zhe Chuan; He, Duanwei

2015-01-01

485

Hydraulic analysis aids high-pressure system design  

SciTech Connect

Transient hydraulic analysis of high pressure gas transmission systems can be used to investigate various areas during design engineering. Practical results can be obtained that give insight into the characteristics of the transportation systems. High-pressure gas transmission systems have particular characteristics that should be considered in a transient hydraulic analysis: prediction of physical and thermodynamic gas properties, tendency for significant Joule-Thomson cooling effects, retrograde condensation of dense phase gases, temperature effects (especially during blowdown). Transient hydraulic analysis is particularly useful for investigating operating characteristics of gas transmission systems in the areas of pipeline system control philosophies and hydraulic flexibility analysis.

Stripling, T.E.; Dillon, K.; Khan, A.U.

1985-01-28

486

High-pressure hydrogen materials compatibility of piezoelectric films  

NASA Astrophysics Data System (ADS)

Hydrogen is well known for materials compatibility issues, including blistering and embrittlement in metals, which are challenges for its use as the next-generation "green" fuel. Beyond metals, hydrogen also degrades piezoelectric materials used as actuators used in direct injection hydrogen internal combustion engines. We present the materials compatibility studies of piezoelectric films in high-pressure hydrogen environments. Absorption of high-pressure hydrogen and composition changes were studied with an elastic recoil detection analysis and Rutherford back-scattering spectrometry in lead zirconate titanate and barium titanate thin films. Hydrogen surface degradation in the form of blistering and Pb mixing was also observed.

Alvine, K. J.; Shutthanandan, V.; Bennett, W. D.; Bonham, C. C.; Skorski, D.; Pitman, S. G.; Dahl, M. E.; Henager, C. H.

2010-11-01

487

Capillary toroid cavity detector for high pressure NMR  

DOEpatents

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)

2007-09-11

488

Synthetic chemistry with periodic mesostructures at high pressure.  

PubMed

Over the last two decades, researchers have studied extensively the synthesis of mesostructured materials, which could be useful for drug delivery, catalytic cracking of petroleum, or reinforced plastics, among other applications. However, until very recently researchers used only temperature as a thermodynamic variable for synthesis, completely neglecting pressure. In this Account, we show how pressure can affect the synthetic chemistry of periodic mesoporous structures with desirable effects. In its simplest application, pressure can crystallize the pore walls of periodic mesoporous silicas, which are difficult to crystallize otherwise. The motivation for the synthesis of periodic mesoporous silica materials (with pore sizes from 2 to 50 nm) 20 years ago was to replace the microporous zeolites (which have pore sizes of <2 nm) in petroleum cracking applications, because the larger pore size of mesoporous materials allows for faster transport of larger molecules. However, these mesoporous materials could not replace zeolite materials because they showed lower hydrothermal stability and lower catalytic activity. This reduced performance has been attributed to the amorphous nature of the mesoporous materials' channel walls. To address this problem, we developed the concept of "nanocasting at high pressure". Through this approach, we produced hitherto-unavailable, periodic mesostructured silicas with crystalline pore walls. In nanocasting, we compress a periodic mesostructured composite (e.g. a periodic mesoporous silica with carbon-filled pores) and subsequently heat it to induce the selective crystallization of one of the two phases. We attain the necessary high pressure for synthesis using piston-cylinder and multianvil apparatuses. Using periodic mesostructured silica/carbon nanocomposites as starting material, we have produced periodic mesoporous coesite and periodic mesoporous quartz. The quartz material is highly stable under harsh hydrothermal conditions (800°C in pure steam), verifying that crystallinity in the channel walls of periodic mesoporous silicas increases their hydrothermal stability. Even without including the carbon phase in the silica pores, we could obtain mesoporous coesite materials. We found similar behavior for periodic mesoporous carbons, which convert into transparent, mesoporous, nanopolycrystalline diamond at high-pressure. We also show that periodic mesoporous materials can serve as precursors for nanocrystals of high-pressure phases. We obtained nearly monodisperse, discrete stishovite nanocrystals from periodic mesoporous silicas and coesite nanocrystals from periodic mesoporous organosilicas. The stishovite nanocrystals disperse in water and form colloidal solutions of individual stishovite nanocrystals. The stishovite nanocrystals could be useful for machining, drilling, and polishing. Overall, the results show that periodic mesoporous materials are suitable starting materials for the synthesis of nanoporous high-pressure phases and nanocrystals of high pressure phases. The substantially enhanced hydrothermal stability seen in periodic mesoporous silicas synthesized at high pressure demonstrates that high pressure can be a useful tool to produce porous materials with improved properties. We expect that synthesis using mesostructures at high pressure can be extended to many other materials beyond silicas and carbons. Presumably, this chemistry can also be extended from mesoporous to microporous and macroporous materials. PMID:23841843

Mandal, Manik; Landskron, Kai

2013-11-19

489

High Pressure Reduction of Selenite by Shewanella oneidensis MR-1  

NASA Astrophysics Data System (ADS)

High-pressure biotopes comprise cold deep-sea environments, hydrothermal vents, and deep subsurface or deep-sea sediments. The latter are less studied, due to the technical difficulties to sample at great depths without contamination. Nevertheless, microbial sulfate reduction and methanogenesis have been found to be spatially distributed in deep deep-sea sediments (1), and sulfate reduction has been shown to be actually more efficient under high hydrostatic pressure (HHP) in some sediments (2). Sulfate-reducing bacteria obtained from the Japan Sea are characterized by an increased sulfide production under pressure (3,4). Unfortunately, investigations of microbial metabolic activity as a function of pressure are extremely scarce due to the experimental difficulty of such measurements at high hydrostatic pressure. We were able to measure the reduction of selenite Se(IV) by Shewanella oneidensis MR-1 as a function of pressure, to 150 MPa using two different high-pressure reactors that allow in situ X-ray spectroscopy measurements on a synchrotron source. A first series of measurements was carried out in a low-pressure Diamond Anvil Cell (DAC) of our own design (5) at ID22 beamline at ESRF (European Synchrotron Radiation Facility); a second one was performed in an autoclave (6) at the BM30B beamline at ESRF. Selenite reduction by strain MR-17 was monitored from ambient pressure to 150 MPa over 25 hours at 30 deg C by XANES spectroscopy (X-ray Analysis of Near Edge Structure). Spectra were recorded hourly in order to quantify the evolution of the oxidation state of selenium with time. Stationary-phase bacteria were inoculated at a high concentration into fresh growth medium containing 5 or 10 M of sodium selenite and 20 mM sodium lactate. Kinetic parameters of the Se (IV) reduction by Shewanella oneidensis strain MR-1 could be extracted from the data, as a function of pressure. They show 1) that the rate constant k of the reaction is decreased by a half at high pressure, and 2) that the yield of the reaction decreases linearly as a function of pressure. From the present study, we can infer the maximum pressure of the metabolism of Se by Shewanella oneidensis strain MR-1 at ca. 160 MPa. The present results indicate that even piezosensitive bacteria can harbor a significant amount of metabolic activity at pressure conditions that are relevant for subsurface geochemical cycles. Moreover, one can hypothetize the same implications in the cycles of more abundant elements, like Fe or Mn. 1 S. D'Hondt, et al., Science 306, 2216-2221 (2004). 2 J. Kallmeyer and A. Boetius, Appl Environ Microbiol 70, 1231-1233 (2004). 3 S. Bale, K. et al., Int J Syst Bacteriol 47, 515-521 (1997). 4 R. J. Parkes, et al. J Microbiol Methods 23, 235-249 (1995). 5 I. Daniel, et al. in prep (2007). 6 D. Testemale, et al. Rev Sci Instrum 76, 043905 (2005). 7 C. R. Myers and K. H. Nealson, J Bacteriol 172, 6232-6238 (1990).

Picard, A.; Daniel, I.; Testemale, D.; Letard, I.; Bleuet, P.; Cardon, H.; Oger, P.

2007-12-01

490

High Pressure Angle Gears: Comparison to Typical Gear Designs  

NASA Technical Reports Server (NTRS)

A preliminary study has been completed to determine the feasibility of using high-pressure angle gears in aeronautic and space applications. Tests were conducted in the NASA Glenn Research Center (GRC) Spur Gear Test Facility at speeds up to 10,000 rpm and 73 N*m (648 in.*lb) for 3.18, 2.12, and 1.59 module gears (8, 12, and 16 diametral pitch gears), all designed to operate in the same test facility. The 3.18 module (8-diametral pitch), 28 tooth, 20deg pressure angle gears are the GRC baseline test specimen. Also, 2.12 module (12-diametral pitch), 42 tooth, 25deg pressure angle gears were tested. Finally 1.59 module (16-diametral pitch), 56 tooth, 35deg pressure angle gears were tested. The high-pressure angle gears were the most efficient when operated in the high-speed aerospace mode (10,000 rpm, lubricated with a synthetic turbine engine oil), and produced the lowest wear rates when tested with a perfluoroether-based grease. The grease tests were conducted at 150 rpm and 71 N*m (630 in.*lb).

Handschuh, Robert F.; Zabrajsek, Andrew J.

2010-01-01

491

Performance of Lanthanum Strontium Manganite Electrodes at High Pressure  

SciTech Connect

The high-pressure performance of lanthanum strontium manganite (LSM), LSM-zirconia, and LSM/ceria composite electrodes was studied by impedance spectroscopy and dc methods. Electrode resistances decreased in proportion to P(O2)1/2 for the LSM electrode in both cathodic and anodic directions to at least 100 atm, a decrease that was attributed to dissociative oxygen adsorption, surface diffusion, and related phenomena. For the LSM-20/zirconia composite electrode, resistances decreased in proportion to P(O2)1/4 across the entire pressure range considered. Two principal features appeared in the impedance spectra, one that showed a P(O2)1/4 dependence attributed to charge transfer reactions, and one that was nearly pressure-independent, possibly due to transport in the zirconia portion of the composite. For the LSM-20/ceria composite electrode, resistances decreased as P(O2)0.3-0.4 at high pressure, depending on temperature. Two features appeared in the impedance spectra: one at low to intermediate frequency having a P(O2)1/2 dependence and one at high frequency having a P(O2)1/4 dependence. These features are attributed to dissociative oxygen adsorption and to charge transfer reactions, respectively. Results suggest that cathodic losses can be substantially lowered by operation of solid oxide fuel cells at greater than ambient pressure.

Thomsen, Edwin C.; Coffey, Greg W.; Pederson, Larry R.; Marina, Olga A.

2009-06-15

492

High pressure injection injury of the foot: a role of negative pressure wound therapy.  

PubMed

High pressure injection injuries (HPII) of the foot are not common in every-day practice. We present a 50-year-old patient with a HPII of the left foot caused by water-gun in a self-inflicted accident working as a technical diver four meters under the sea surface. Surgical treatment included extensive debridement of necrotic tissue and fibrin deposits and removal of foreign material. A negative pressure wound therapy (NPWT) device was applied resulting in a good wound base for subsequent skin grafting leading to a good functional and cosmetic outcome. PMID:24060024

Marinovic, Marin; Bakota, Bore; Spanjol, Josip; Sosa, Ivan; Grzalja, Nikola; Gulan, Gordan; Ivancic, Aldo; Cicvaric, Tedi

2013-09-01

493

Constructing high-pressure thermodynamic models: problems and possible solutions  

NASA Astrophysics Data System (ADS)

Conventional thermodynamic databases (e.g. Fabrichnaya et al. 2004, Holland and Powell 1998, 2011) consist of expressions for the Gibbs energy at ambient pressure, extended to higher pressures through the integration of some EOS (Equation Of State). While this is simple and straight-forward, such thermodynamic models are prone to produce manifestly unphysical predictions of negative thermal expansion and even negative heat capacity at high pressure. It has been shown (Brosh et al. 2007) that these errors arise not only from problems the EOS itself but also from incompatibilities between the EOS and the models used for extrapolations of the heat capacity at ambient pressure. One solution is a radical restructuring of thermodynamic databases. Instead of modelling the Gibbs energy, new databases can be based on modelling the Helmholtz energy using Debye-Mie-Grüneisen EOS. This approach is very successful for modelling solid substances (Jacobs 2009, 2010, Dorogokupets et al. 2007, 2012) but the Debye-Mie-Grüneisen equations of state are not easily applicable to liquids. Other difficulties stem from the treatment of the predicted mechanical instability above the normal melting point. However, the most severe difficulty with the utilization of the Debye-Mie-Grüneisen approach is that it is incompatible with the current ambient-pressure thermodynamic databases and one will not be able to use them as a basis for high pressure modelling. Another approach (Brosh et al. 2007) is based on an interpolation of the thermophysical properties between the ambient pressure models given in conventional databases and the Debye-Mie-Grüneisen model at extreme pressures. This avoids most of the spurious anomalies of conventional models. The limitations of the interpolation scheme are the inclusion of several model parameters whose physical essence is not well-defined and an underestimation of the heat capacity at high pressures. In this presentation, the predictions of the interpolation scheme are compared with those of more physical Debye-Mie-Grüneisen models for several substances: Al, Fe and MgO. The utility of the interpolation scheme in calculating phase equilibria and thermophysical properties from ambient to earth-core pressures is illustrated by calculations on the Fe-Ni-C alloy system.

Brosh, E.

2013-12-01

494

High pressure ratio cryocooler with integral expander and heat exchanger  

NASA Astrophysics Data System (ADS)

A new 1 W, 4.2 K cryocooler is under development that is intended to miniaturize helium temperature refrigeration systems using a high-pressure-ratio Collins-type cycle. The configuration resulted from optimization studies of a saturated vapor compression (SCV) cycle that employs miniature parallel-plate heat exchangers. The basic configuration is a long displacer in a close-fitting, thin-walled cylinder. The displacer-to-cylinder gap is the high-pressure passage of the heat exchanger, and the low-pressure passage is formed by a thin tube over the OD of the cylinder. A solenoid-operated inlet valve admits 40 atm helium to the displacer-to-cylinder gap at room temperature, while the solenoid-operated exhaust valve operates at 4 atm. The single-stage cryocooler produces 1 W of refrigeration at 40 K without precooling and at 20 K with liquid nitrogen precooling.

Crunkleton, J. A.; Smith, J. L., Jr.; Iwasa, Y.

495

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

E-print Network

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

2012-06-07

496

Phase Diagram of RDX Crystals at High Pressures and Temperatures  

NASA Astrophysics Data System (ADS)

A knowledge of the RDX phase diagram is important for understanding shock-induced decomposition of RDX. Vibrational spectroscopy and optical imaging in a diamond anvil cell were used to examine the RDX behavior at high pressures and temperatures. Interplay between three solid (?, ?, ?), liquid, and decomposed phases was examined in experiments on single crystals at pressures up to 12.0 GPa and temperatures to 600 K. Several distinct pressure regions were found in the RDX response at elevated temperatures. The boundaries between the ?, ?, and ? phases were determined with a triple point at 3.7 GPa and ˜ 466 K. The ?-? phase transition was confirmed to be reversible and to occur at the same pressure 3.7 GPa, regardless of temperature. The ?-phase was found to exist only in a narrow range of pressures, from 2.8 to 6.0 GPa. Below and above these pressures, ?- or ?-RDX cryst