Effect of some graphite-related factors on diamonds synthesized in the cobalt-carbon system at high pressure

1985 ◽  
Vol 4 (2) ◽  
pp. 141-143 ◽  
Author(s):  
G. Bocquillon ◽  
C. Loriers-Susse ◽  
J. Loriers
Keyword(s):  
High Pressure ◽  
Related Factors ◽  
Carbon System

Explaining the Sources of de facto Federalism in Reform China: Intergovernmental Decentralization, Globalization, and Central–Local Relations

2006 ◽  
Vol 7 (2) ◽  
pp. 101-126 ◽  
Author(s):  
YONGNIAN ZHENG
Keyword(s):  
High Pressure ◽  
Political System ◽  
The Political ◽  
Related Factors ◽  
Chinese Leadership

China does not have a federalist system of government. Nevertheless, with deepening reform and openness, China's political system in terms of central–local relations is functioning more and more like federalism. Federalism as a functioning system in China has been understudied. This paper defines the political system existing in China as de facto federalism, and attempts to explore the sources and dynamics of this de facto federalism. China's de facto federalism was mainly driven by two related factors, i.e. decentralization and globalization. This paper argues that while economic decentralization in the 1980s led to the formation of de facto federalism, globalization since the 1990s has accelerated this process and generated increasingly high pressure on the Chinese leadership to institutionalize existing de facto federalism.

scholarly journals Route to high-$$T_{c}$$ superconductivity of $$\hbox {BC}_{{7}}$$ via strong bonding of boron–carbon compound at high pressure

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Prutthipong Tsuppayakorn-aek ◽  
Xiaoyong Yang ◽  
Prayoonsak Pluengphon ◽  
Wei Luo ◽  
Rajeev Ahuja ◽  
...  
Keyword(s):  
High Pressure ◽  
Surface Shape ◽  
First Principles Calculation ◽  
Chemical Bonds ◽  
Superconducting Transition ◽  
Covalent Bonds ◽  
Large Sheet ◽  
Very High ◽  
Carbon System ◽  
Boron Carbon

Abstract We have analyzed the compositions of boron–carbon system, in which the $$\hbox {BC}_{{7}}$$ BC 7 compound is identified as structural stability at high pressure. The first-principles calculation is used to identify the phase diagram, electronic structure, and superconductivity of $$\hbox {BC}_{{7}}$$ BC 7 . Our results have demonstrated that the $$\hbox {BC}_{{7}}$$ BC 7 is thermodynamically stable in the diamond-like $$P{\bar{4}}m2$$ P 4 ¯ m 2 structure at a pressure above 244 GPa, and under temperature also. Feature of chemical bonds between B and C atoms is presented using the electron localization function. The strong chemical bonds in diamond-like $$P{\bar{4}}m2$$ P 4 ¯ m 2 structure are covalent bonds, and it exhibits the s–p hybridization under the pressure compression. The Fermi surface shape displays the large sheet, indicating that the diamond-like $$P{\bar{4}}m2$$ P 4 ¯ m 2 phase can achieve a high superconducting transition temperature ($$\hbox {T}_{{c}}$$ T c ). The outstanding property of $$\hbox {BC}_{{7}}$$ BC 7 at 250 GPa has manifested very high-$$\hbox {T}_{{c}}$$ T c of superconductivity as 164 K, indicating that the carbon-rich system can induce the high-$$\hbox {T}_{{c}}$$ T c value as well.

Diamond Crystallization from an Antimony–Carbon System under High Pressure and Temperature

2015 ◽  
Vol 15 (5) ◽  
pp. 2539-2544 ◽  
Author(s):  
Yuri N. Palyanov ◽  
Yuri M. Borzdov ◽  
Igor N. Kupriyanov ◽  
Yuliya V. Bataleva ◽  
Alexander F. Khokhryakov ◽  
...  
Keyword(s):  
High Pressure ◽  
High Pressure And Temperature ◽  
Diamond Crystallization ◽  
Carbon System

Diamond Growth from a Phosphorus–Carbon System at High Pressure High Temperature Conditions

2011 ◽  
Vol 11 (6) ◽  
pp. 2599-2605 ◽  
Author(s):  
Yuri N. Palyanov ◽  
Igor N. Kupriyanov ◽  
Alexander G. Sokol ◽  
Alexander F. Khokhryakov ◽  
Yuri M. Borzdov
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Diamond Growth ◽  
Temperature Conditions ◽  
High Pressure High Temperature ◽  
Carbon System

Effects of FeNi-phosphorus-carbon system on crystal growth of diamond under high pressure and high temperature conditions

2015 ◽  
Vol 24 (3) ◽  
pp. 038101 ◽  
Author(s):  
Mei-Hua Hu ◽  
Ning Bi ◽  
Shang-Sheng Li ◽  
Tai-Chao Su ◽  
Ai-Guo Zhou ◽  
...  
Keyword(s):  
High Pressure ◽  
Crystal Growth ◽  
High Temperature ◽  
Temperature Conditions ◽  
Carbon System

Comparison for Steady and Unsteady Simulations for High Pressure Turbine

2002 ◽  
Author(s):  
N. Liamis ◽  
O. Sgarzi ◽  
E. M. El Ghazzani
Keyword(s):  
High Pressure ◽  
Development Program ◽  
Navier Stokes ◽  
High Pressure Turbine ◽  
Related Factors ◽  
Multi Stage ◽  
Steady Stage ◽  
Flow Information ◽  
Aero Engines ◽  
Turbine Design

For the new generation of advanced aero-engines, the turbine design is a key issue to most of the critical engine related factors, such as fuel consumption, component life, weight, duration and cost of the development program. For many years, an important effort has been devoted at Snecma Moteurs to the development, the validation and the industrialization of methods for the prediction of aerothermal phenomena in multi-stage turbines. The purpose of this contribution is to report on the recent advances of Snecma Moteurs CFD tools for aerodynamic turbine design and analysis. Three approaches, based on 3D Navier-Stokes calculations, each of them corresponding to a different level of complexity, are presented for the prediction of the aerodynamic behavior of high pressure turbines, showing the degree of accuracy and maturity that the turbine aerothermal methods of Snecma Moteurs, have now reached. Firstly, two types of steady stage simulation are considered. The first one uses the mixing plane method in order to transfer the flow information between adjacent blade rows, while the second one uses the average passage method proposed by Adamczyk [1]. Finally, the contribution of an unsteady stage simulation is investigated. Comparisons between computational results and experimental data for a high pressure turbine, tested in the frame of the European Research Programs IACA and TATEF are presented. An analysis is also performed, showing the advantages and the drawbacks of each approach for a realistic representation of the flow into a high pressure turbine stage.

High-pressure synthesis and characterization of diamond from a sulfur–carbon system

2001 ◽  
Vol 10 (12) ◽  
pp. 2145-2152 ◽  
Author(s):  
Yu Pal'yanov ◽  
Yu Borzdov ◽  
I Kupriyanov ◽  
V Gusev ◽  
A Khokhryakov ◽  
...  
Keyword(s):  
High Pressure ◽  
Synthesis And Characterization ◽  
High Pressure Synthesis ◽  
Pressure Synthesis ◽  
Carbon System

High-pressure freezing of cells in suspension for low-voltage scanning electron microscopy (LVSEM)

1991 ◽  
Vol 49 ◽  
pp. 64-65
Author(s):  
Marek Malecki ◽  
James Pawley ◽  
Hans Ris
Keyword(s):  
Electron Microscopy ◽  
High Pressure ◽  
Low Voltage ◽  
Culture Media ◽  
Cell Structure ◽  
Freeze Substitution ◽  
Ice Crystal ◽  
High Pressure Freezing ◽  
Cell Culture Media ◽  
Voltage Scanning

The ultrastructure of cells suspended in physiological fluids or cell culture media can only be studied if the living processes are stopped while the cells remain in suspension. Attachment of living cells to carrier surfaces to facilitate further processing for electron microscopy produces a rapid reorganization of cell structure eradicating most traces of the structures present when the cells were in suspension. The structure of cells in suspension can be immobilized by either chemical fixation or, much faster, by rapid freezing (cryo-immobilization). The fixation speed is particularly important in studies of cell surface reorganization over time. High pressure freezing provides conditions where specimens up to 500μm thick can be frozen in milliseconds without ice crystal damage. This volume is sufficient for cells to remain in suspension until frozen. However, special procedures are needed to assure that the unattached cells are not lost during subsequent processing for LVSEM or HVEM using freeze-substitution or freeze drying. We recently developed such a procedure.

Prolonged Fixation Studies For Spaceflight

1973 ◽  
Vol 31 ◽  
pp. 332-333
Author(s):  
Robert Corbett ◽  
Delbert E. Philpott ◽  
Sam Black
Keyword(s):  
High Pressure ◽  
Living Systems ◽  
Prolonged Storage ◽  
Time Intervals ◽  
Early Signs ◽  
Large Numbers

Observation of subtle or early signs of change in spaceflight induced alterations on living systems require precise methods of sampling. In-flight analysis would be preferable but constraints of time, equipment, personnel and cost dictate the necessity for prolonged storage before retrieval. Because of this, various tissues have been stored in fixatives and combinations of fixatives and observed at various time intervals. High pressure and the effect of buffer alone have also been tried.Of the various tissues embedded, muscle, cartilage and liver, liver has been the most extensively studied because it contains large numbers of organelles common to all tissues (Fig. 1).

Cryosectioning plant roots prepared by high-pressure freezing

1987 ◽  
Vol 45 ◽  
pp. 662-663
Author(s):  
R.E. Crang ◽  
M. Mueller ◽  
K. Zierold
Keyword(s):  
High Pressure ◽  
Cell Walls ◽  
Plant Tissues ◽  
Ice Crystal ◽  
High Pressure Freezing ◽  
Vitreous State ◽  
Radial Depth ◽  
Irregular Topography ◽  
Considerable Depth ◽  
Conventional Freezing

Obtaining frozen-hydrated sections of plant tissues for electron microscopy and microanalysis has been considered difficult, if not impossible, due primarily to the considerable depth of effective freezing in the tissues which would be required. The greatest depth of vitreous freezing is generally considered to be only 15-20 μm in animal specimens. Plant cells are often much larger in diameter and, if several cells are required to be intact, ice crystal damage can be expected to be so severe as to prevent successful cryoultramicrotomy. The very nature of cell walls, intercellular air spaces, irregular topography, and large vacuoles often make it impractical to use immersion, metal-mirror, or jet freezing techniques for botanical material.However, it has been proposed that high-pressure freezing (HPF) may offer an alternative to the more conventional freezing techniques, inasmuch as non-cryoprotected specimens may be frozen in a vitreous, or near-vitreous state, to a radial depth of at least 0.5 mm.

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