Pyrite form of group-14 element pernitrides synthesized at high pressure and high temperature

2017 ◽  
Vol 46 (30) ◽  
pp. 9750-9754 ◽  
Author(s):  
K. Niwa ◽  
H. Ogasawara ◽  
M. Hasegawa
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
High Temperatures ◽  
High Pressures ◽  
Group 14

The incompressible pyrite form of group 14 elemental pernitrides synthesized at high pressures and high temperatures.

Reciprocating Shaft Seals for High-Temperature and High-Pressure Applications: A Review

2017 ◽  
Vol 140 (3) ◽  
Author(s):  
Michael McKee ◽  
Faramarz Gordaninejad
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
High Temperatures ◽  
High Pressures ◽  
Fiber Reinforcement ◽  
Shaft Seals ◽  
Scientific Topic ◽  
Temperature Applications

This study reviews the work performed in the field of reciprocating shaft seals from the advent of the scientific topic in the 1940s. Concepts of leakage, film layers, friction, wear, and other concerns with shaft seals are discussed. The importance of shaft seals as it pertains to liquid springs is brought to light along with issues requiring a need for these seals to withstand high temperatures and high pressures. Issues resulting from a seal exposure to high temperatures, such as thermosetting and embrittlement, are discussed in conjunction with materials and properties that allow seals to operate in high-temperature environments. High-pressure sealing challenges are identified along with the techniques currently employed to overcome these issues, such as fiber reinforcement and backup rings. Sealing solutions have been implemented independently for both high-pressure and high-temperature applications; however, the combination of high pressures coupled with high temperatures is still a challenge today.

scholarly journals Gaseous combustion at high pressures. —Part X. The co-volume corrections, maximum temperatures and dissociation of steam and carbon dioxide in explosions

1928 ◽  
Vol 119 (782) ◽  
pp. 464-480
Keyword(s):  
Carbon Dioxide ◽  
High Pressure ◽  
Internal Energy ◽  
High Temperatures ◽  
High Pressures ◽  
Internal Combustion ◽  
Systematic Survey ◽  
Explosion Method ◽  
Maximum Temperatures ◽  
Very High

During the researches upon high-pressure explosions of carbonic oxide-air, hydrogen-air, etc., mixtures, which have been described in the previous papers of this series, a mass of data has been accumulated relating to the influence of density and temperature upon the internal energy of gases and the dissociation of steam and carbon dioxide. Some time ago, at Prof. Bone’s request, the author undertook a systematic survey of the data in question, and the present paper summarises some of the principal results thereof, which it is hoped will throw light upon problems interesting alike to chemists, physicists and internal-combustion engineers. The explosion method affords the only means known at present of determining the internal energies of gases at very high temperatures, and it has been used for this purpose for upwards of 50 years. Although by no means without difficulties, arising from uncertainties of some of the assumptions upon which it is based, yet, for want of a better, its results have been generally accepted as being at least provisionally valuable. Amongst the more recent investigations which have attracted attention in this connection should be mentioned those of Pier, Bjerrum, Siegel and Fenning, all of whom worked at low or medium pressures.

scholarly journals Synthesis of Star-Shaped Boron Carbide Micro-Crystallites under High Pressure and High Temperatures

Crystals ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 448
Author(s):  
Vladimir Filonenko ◽  
Pavel Zinin ◽  
Igor Zibrov ◽  
Alexander Anokhin ◽  
Elena Kukueva ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Boron Carbide ◽  
Carbon Content ◽  
High Temperatures ◽  
Low Carbon

We synthesized star-shaped pentagonal microcrystals of boron carbide with an extremely low carbon content (~5%), from m-carborane under high pressure (7 GPa) and high temperature (1370–1670 K). These crystals have five-fold symmetry and grow in the shape of stars. A 5-fold symmetry in large micron-sized crystals is extremely rare making this a striking observation.

Antioxidant Activity of Enzymatic Hydrolysates of High-Temperature Soybean Meal Pretreated with High Pressures

2015 ◽  
Vol 1092-1093 ◽  
pp. 1519-1524 ◽  
Author(s):  
Jing Xu ◽  
Yu Ting Wang ◽  
Xiao Yu Wang ◽  
Xin Ru Li ◽  
Qian Xin Dang
Keyword(s):  
Antioxidant Activity ◽  
High Pressure ◽  
Superoxide Dismutase ◽  
High Temperature ◽  
Glutathione Peroxidase ◽  
Molecular Mass ◽  
Soybean Meal ◽  
High Pressures ◽  
Relative Molecular Mass ◽  
Mda Content

Effect of high-temperature soybean meal hydrolysates was to be studied in this paper. Hhigh-temperature soybean meal was treated by high pressure. And Alcalase 2.4 L was used to hydrolyze high-temperature soybean meal, three kinds of solutions with relative molecular mass of > 10 000 Da, 5000 Da – 10 000 Da and < 5 000 Da were obtained by ultrafiltration of hydrolysates, and they were administrated mice by gastric perfusion, respectively. Levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX) and malondialdehyde (MDA) in liver were separately tested with reagent kits. Results showed that SOD and GSH-PX activities were significantly improved and MDA content was reduced in liver of mice by hydrolysates, which indicated that high-temperature soybean meal hydrolysates can improve antioxidant indexes of mice and enhance antioxidation capacity of body.

Advances in Computation of Temperature-Pressure Phase Diagrams of High-Pressure Nitrides

2008 ◽  
Vol 403 ◽  
pp. 77-80 ◽  
Author(s):  
Peter Kroll
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Elevated Temperature ◽  
Total Energy ◽  
Phase Diagrams ◽  
High Pressures ◽  
First Principle ◽  
Energy Calculations ◽  
High Pressure High Temperature ◽  
Pressure Phase

A combination of first-principle and thermochemical calculations is applied to compute the phase diagrams of rhenium-nitrogen and of ruthenium-nitrogen at elevated temperature and high pressure. We augment total energy calculations with our approach to treat the nitrogen fugacity at high pressures. We predict a sequential nitridation of Re at high-pressure/high-temperature conditions. At 3000 K, ReN will form from Re and nitrogen at about 32 GPa. A ReN2 with CoSb2-type structure may be achieved at pressures exceeding 50 GPa at this temperature. Marcasite-type RuN2 will be attainable at 3000 K at pressures above 30 GPa by reacting Ru with nitrogen.

A Study for N2 Coherent Anti-Stokes Raman Spectroscopy Thermometry at High Pressure

1983 ◽  
Vol 37 (6) ◽  
pp. 508-512 ◽  
Author(s):  
Haruhiko Kataoka ◽  
Shiro Maeda ◽  
Chiaki Hirose ◽  
Koichi Kajiyama
Keyword(s):  
Raman Spectroscopy ◽  
High Pressure ◽  
High Temperature ◽  
Pressure Range ◽  
High Pressures ◽  
Band Width ◽  
Maximum Height ◽  
Temperature Determination ◽  
Engine Cylinder ◽  
Anti Stokes

N2 coherent anti-Stokes Raman spectroscopy (CARS) thermometry over a pressure range 1 to 50 atm has been studied. The CARS profile at high pressure and high temperature was recorded by using the ignition inside a running engine cylinder. The observed Q-branch profile was theoretically fitted by incorporating the collisional narrowing effect, serving for the temperature determination at various pressures. Because of the narrowing effect, the apparent band width showed little change with pressure above 5 atm in general. It has been suggested that the band width at 1/5 of the maximum height can be a useful measure of temperature, while the usual half-width turns out to be hardly practicable at high pressures.

Structural stability of WS2 under high pressure

2014 ◽  
Vol 28 (25) ◽  
pp. 1450168 ◽  
Author(s):  
Nirup Bandaru ◽  
Ravhi S. Kumar ◽  
Jason Baker ◽  
Oliver Tschauner ◽  
Thomas Hartmann ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Pressure ◽  
High Temperature ◽  
Structural Changes ◽  
High Pressures ◽  
Structural Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diamond Anvil ◽  
Heating Up

Structural behavior of bulk WS 2 under high pressure was investigated using synchrotron X-ray diffraction and diamond anvil cell up to 52 GPa along with high temperature X-ray diffraction and high pressure Raman spectroscopy analysis. The high pressure results obtained from X-ray diffraction and Raman analysis did not show any pressure induced structural phase transformations up to 52 GPa. The high temperature results show that the WS 2 crystal structure is stable upon heating up to 600°C. Furthermore, the powder X-ray diffraction obtained on shock subjected WS 2 to high pressures up to 10 GPa also did not reveal any structural changes. Our results suggest that even though WS 2 is less compressible than the isostructural MoS 2, its crystal structure is stable under static and dynamic compressions up to the experimental limit.

Thermal and Pressure-Assisted Thermal Destruction Kinetics for Spores of Type A Clostridium botulinum and Clostridium sporogenes PA3679

2016 ◽  
Vol 79 (2) ◽  
pp. 253-262 ◽  
Author(s):  
N. RUKMA REDDY ◽  
EDUARDO PATAZCA ◽  
TRAVIS R. MORRISSEY ◽  
GUY E. SKINNER ◽  
VIVIANA LOEZA ◽  
...  
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
High Temperatures ◽  
Clostridium Botulinum ◽  
Pilot Scale ◽  
Inactivation Kinetics ◽  
Clostridium Sporogenes ◽  
Log Reduction ◽  
Pressure Test ◽  
D Values

ABSTRACT The purpose of this study was to determine the inactivation kinetics of the spores of the most resistant proteolytic Clostridium botulinum strains (Giorgio-A and 69-A, as determined from an earlier screening study) and of Clostridium sporogenes PA3679 and to compare the thermal and pressure-assisted thermal resistance of these spores. Spores of these strains were prepared using a biphasic medium method. C. sporogenes PA3679 spores were heat treated before spore preparation. Using laboratory-scale and pilot-scale pressure test systems, spores of Giorgio-A, 69-A, and PA3679 suspended in ACES [N-(2-acetamido)-2-aminoethanesulfonic acid] buffer (pH 7.0) were exposed to various combinations of temperature (93 to 121°C) and pressure (0.1 to 750 MPa) to determine their resistance. More than a 5-log reduction occurred after 3 min at 113°C for spores of Giorgio-A and 69-A and after 5 min at 117°C for spores of PA3679. A combination of high temperatures (93 to 121°C) and pressures yielded greater log reductions of spores of Giorgio-A, 69-A, and PA3679 compared with reduction obtained with high temperatures alone. No survivors from initial levels (&gt;5.0 log CFU) of Giorgio-A and 69-A were detected when processed at a combination of high temperature (117 and 121°C) and high pressure (600 and 750 MPa) for &lt;1 min in a pilot-scale pressure test system. Increasing pressure from 600 to 750 MPa at 117°C decreased the time from 2.7 to 1 min for a &gt;4.5-log reduction of PA3679 spores. Thermal D-values of Giorgio-A, 69-A, and PA3679 spores decreased (i.e., 29.1 to 0.33 min for Giorgio-A, 40.5 to 0.27 min for 69-A, and 335.2 to 2.16 min for PA3679) as the temperature increased from 97 to 117°C. Pressure-assisted thermal D-values of Giorgio-A, 69-A, and PA3679 also decreased as temperature increased from 97 to 121°C at both pressures (600 and 750 MPa) (i.e., 17.19 to 0.15 min for Giorgio-A, 9.58 to 0.15 min for 69-A, and 12.93 to 0.33 min for PA3679 at 600 MPa). At higher temperatures (117 or 121°C), increasing pressure from 600 to 750 MPa had an effect on pressure-assisted thermal D-values of PA3679 (i.e., at 117°C, pressure-assisted thermal D-value decreased from 0.55 to 0.28 min as pressure increased from 600 to 750 MPa), but pressure had no effect on pressure-assisted thermal D-values of Giorgio-A and 69-A. When compared with Giorgio-A and 69-A, PA3679 had higher thermal and pressure-assisted thermal D-values. C. sporogenes PA3679 spores were generally more resistant to combinations of high pressure and high temperature than were the spores of the C. botulinum strains tested in this study.

scholarly journals Corrosion-resistant systems of formate packer fluid for G3/N80/TP110SS pipes at high temperature, high pressure and high H 2 S/CO 2 ratios

2018 ◽  
Vol 5 (7) ◽  
pp. 180405 ◽  
Author(s):  
Peng Xu ◽  
Zhengwu Tao ◽  
Zhihong Wang
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Corrosion Rate ◽  
Corrosion Protection ◽  
High Pressures ◽  
Gas Production ◽  
Corrosion Mechanism ◽  
Acid Gas ◽  
High Acid ◽  
High Temperature High Pressure

A series of corrosion problems caused by high-temperature, high-pressure and high-acid gas environments has been an issue in oil and gas production for a long time. During the development of a high-acid gas field, the petroleum pipe is subjected to many aspects of corrosion, and the corrosion mechanism is complicated by the condition of the coexistence of H 2 S/CO 2 . Based on the study of the corrosion problem associated with the formate packer fluid in Southwest China, three kinds of steels were studied for corrosion prevention in the alloy G3/N80 steel/TP110SS steel. The study shows that the corrosion rate of the formate packer fluid is low, but corrosion is severe in environments characterized by high temperatures, high pressures and high-acid gas contents. Based on the consideration of cost and the difficulty of realization, an anti-corrosion system was constructed based on the existing packer fluid, mainly through the introduction of a variety of anti-corrosion additives. Through the selection of various additives and corrosion experiments, a corrosion protection system of formate packer fluid was developed. Corrosion tests show that the corrosion rate of the system must be less than 0.076 mm yr −1 to achieve the purpose of corrosion protection. The formate packer fluid with corrosion protection can meet the needs of the current application.

High Temperature, High-Pressure Fluid Connections for Power Micro-Systems

2000 ◽  
Vol 657 ◽  
Author(s):  
Todd S. Harrison ◽  
Adam P. London ◽  
S. Mark Spearing
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
High Power ◽  
High Pressures ◽  
Mechanical Test ◽  
Electrical Power ◽  
Surface Preparation ◽  
Rocket Engines ◽  
Macro Scale ◽  
Micro Systems

ABSTRACTHigh power density micro-systems offer the potential to revolutionize technologies for portable electrical power generation, propulsion and flow control. Devices are being designed and fabricated which include micro-gas turbine engines, micro-rocket engines, micro-motor- compressors, micro-pumps and micro-hydraulic transducers. Common to all of this family of devices is the need to create packages that service the devices, and interface them with the macro-scale environment. Fluid interconnections are a particularly demanding packaging element for this class of devices. In order to achieve high power densities, these devices are required to operate at high pressures and, in some cases, high temperatures. This paper describes the design, analysis, fabrication and testing of high-pressure, high temperature fluid connections for the micro-engine and micro-rocket applications. A glass bonding technology has been developed to allow the creation of multiple fluidic connections consisting of Ni/Fe alloy tubes to silicon devices. Key strategies to achieve high strength connections are: to minimize the mismatch in coefficients of thermal expansion between the components, to eliminate voids from the glass and to promote adequate wetting of the glass to both the tubes and the silicon. Mechanical test results are presented which correlate the strength and statistical reliability of such bonds to the processing conditions, choice of glass and surface preparation prior to bonding. Successful examples of packaged micro-engine and micro-rocket devices are presented.

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