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.

scholarly journals Boron carbide composites with highly aligned graphene nanoplatelets: light-weight and efficient electromagnetic interference shielding materials at high temperatures

RSC Advances ◽  
2018 ◽  
Vol 8 (69) ◽  
pp. 39314-39320 ◽  
Author(s):  
Y. Q. Tan ◽  
H. Luo ◽  
X. S. Zhou ◽  
S. M. Peng ◽  
H. B. Zhang
Keyword(s):  
High Temperature ◽  
Boron Carbide ◽  
High Temperatures ◽  
Electromagnetic Interference ◽  
Graphene Nanoplatelets ◽  
Light Weight ◽  
Electromagnetic Interference Shielding ◽  
Shielding Composites

The incorporation of a small amount of highly aligned graphene nanoplatelets into boron carbide leads to light-weight and efficient high-temperature electromagnetic interference shielding composites.

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.

SANDVIK 3R12

Alloy Digest ◽  
1995 ◽  
Vol 44 (9) ◽  
Keyword(s):  
Fracture Toughness ◽  
Stainless Steel ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Physical Properties ◽  
Carbon Content ◽  
Tensile Properties ◽  
Heat Treating ◽  
Low Carbon ◽  
Temperature Performance

Abstract Sandvik 3R12 is an austenitic chromium-nickel stainless steel with extra low carbon content. It is superior to Type 302 in corrosion resistance. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-612. Producer or source: Sandvik.

CRONIFER 2522 LCN

Alloy Digest ◽  
1983 ◽  
Vol 32 (8) ◽  
Keyword(s):  
Corrosion Resistance ◽  
High Temperature ◽  
Physical Properties ◽  
Surface Treatment ◽  
Carbon Content ◽  
Heat Treating ◽  
Low Carbon ◽  
Corrosion Rates ◽  
Temperature Performance ◽  
Molybdenum Steel

Abstract CRONIFER 2522 LCN is a fully austenitic chromium-nickel-molybdenum steel with an extremely low carbon content (0.020% maximum). It contains 0.10-0.14% nitrogen. It is outstanding because of its very low corrosion rates in the Huey test. CRONIFER 2522 LCN is recommended especially for those parts of urea plants that are subjected to the most corrosive conditions. This datasheet provides information on composition, physical properties, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: SS-430. Producer or source: Vereingte Deutsche Metallwerke AG.

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.

Tailoring Carbon Nanoclusters to Desired Morphologies

1998 ◽  
Vol 13 (9) ◽  
pp. 2438-2444 ◽  
Author(s):  
Jun Jiao ◽  
Supapan Seraphin
Keyword(s):  
Carbon Monoxide ◽  
High Temperature ◽  
Carbon Content ◽  
Arc Discharge ◽  
Low Carbon ◽  
High Carbon ◽  
High Carbon Content ◽  
Carbon Nanoclusters ◽  
Comparative Manner

The preparation and structural characterization of carbon nanoclusters of different morphologies produced by three different methods and under a variety of conditions is reported. In a comparative manner, the growth phenomena and structural properties of carbon nanoclusters are investigated as synthesized by (a) the high temperature (˜3000 °C) and high carbon-content process of the conventional arc-discharge, (b) the high temperature but low carbon-content process of the modified arc-discharge, and finally (c) the relatively low temperature (˜500 °C) process of Ni catalytic disproportionation of carbon monoxide.

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 (>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 <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 >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.

The Synthesis from α-SiO2 and Graphite System to Coesite under High Temperature High Pressure

2014 ◽  
Vol 1051 ◽  
pp. 299-302
Author(s):  
De Jun Wang ◽  
Run Ru Liu ◽  
Leng Jing ◽  
Xin Yu Bai
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Carbon Content ◽  
Powder Mixture ◽  
Mechanical Milling ◽  
Graphite Powder ◽  
High Energy ◽  
Mass Ratio ◽  
Synthesis Conditions ◽  
High Temperature High Pressure

Taking α-quartz of different mass ratio mixed with graphite powder mixture as the initial materials, using the method of combining high-energy mechanical milling with high pressure and high temperature , this work inspected the influences of carbon content on the synthesis conditions of coesite. The experimental products were measured by XRD, TEM, and Raman. The results showed that the existence of carbon can obviously inhibit the formation of coesite, and the higher carbon content of initial materials the higher pressure on forming coesite is needed.

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