Large-area goaf fires: a numerical method for locating high-temperature zones and assessing the effect of liquid nitrogen fire control

2016 ◽  
Vol 75 (21) ◽  
Author(s):  
Botao Qin ◽  
Hetang Wang ◽  
Junzhe Yang ◽  
Leizheng Liu
Keyword(s):  
High Temperature ◽  
Numerical Method ◽  
Liquid Nitrogen ◽  
Large Area ◽  
Fire Control

High Temperature Thermoelectric Device Concept Using Large Area PN Junctions

2014 ◽  
Vol 43 (6) ◽  
pp. 2376-2383 ◽  
Author(s):  
R. Chavez ◽  
S. Angst ◽  
J. Hall ◽  
J. Stoetzel ◽  
V. Kessler ◽  
...  
Keyword(s):  
High Temperature ◽  
Thermoelectric Device ◽  
Large Area ◽  
Pn Junctions

The small spacecraft with a magnetic sail on high-temperature superconductors

2021 ◽  
pp. 51-61
Author(s):  
Timur Sh. KOMBAEV ◽  
Mikhail K. ARTEMOV ◽  
Valentin K. SYSOEV ◽  
Dmitry S. DEZHIN
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
High Temperature ◽  
Shape Memory ◽  
New Technologies ◽  
High Temperature Superconductors ◽  
Solar Wind Plasma ◽  
Large Area ◽  
Small Spacecraft ◽  
Shape Memory Materials

It is proposed to develop a small spacecraft for an experiment using high-temperature superconductors (HTS) and shape memory materials. The purpose of the experiment is to test a technological capability of creating a strong magnetic field on the small spacecraft using HTS and shape memory materials for deployed large-area structures, and study the magnetic field interaction with the solar wind plasma and the resulting force impact on the small spacecraft. This article is of a polemical character and makes it possible to take a fresh look at the applicability of new technologies in space-system engineering. Key words: high-temperature superconductors, shape memory materials, solar wind, spacecraft.

The Formation of an Epitaxial-Graphene Cap Layer for Post-Implantation High Temperature Annealing of SiC and its In Situ Removal by Si-Vapor Etching

2011 ◽  
Vol 679-680 ◽  
pp. 777-780 ◽  
Author(s):  
Shoji Ushio ◽  
Ayumu Adachi ◽  
Kazuhiro Matsuda ◽  
Noboru Ohtani ◽  
Tadaaki Kaneko
Keyword(s):  
High Temperature ◽  
Graphene Layer ◽  
Treatment Method ◽  
Etch Depth ◽  
High Temperature Annealing ◽  
Large Area ◽  
Vapor Flux ◽  
Precise Control ◽  
Post Implantation

As a new graphene functionality applicable to post-implantation high temperature annealing of SiC, a method of in situ formation and removal of large area epitaxial few-layer graphene on 4H-SiC(0001) Si-face is proposed. It is demonstrated that the homogeneous graphene layer formed by Si sublimation can be preserved without the decomposition of the underlying SiC substrate even in the excess of 2000 oC in ultrahigh vacuum. It is due to the existence of the stable (6√3×6√3) buffer layer at the interface. To ensure this cap function, the homogeneity of the interface must be guaranteed. In order to do that, precise control of the initial SiC surface flatness is required. Si-vapor etching is a simple and versatile SiC surface pre/post- treatment method, where thermally decomposed SiC surface is compensated by a Si-vapor flux from Si solid source in the same semi-closed TaC container. While this Si-vapor etching allows precise control of SiC etch depth and surface step-terrace structures, it also provides a “decap” function to remove of the graphene layer. The surface properties after the each process were characterized by AFM and Raman spectroscopy.

Diamond Films: Recent Developments

MRS Bulletin ◽  
1998 ◽  
Vol 23 (9) ◽  
pp. 16-21 ◽  
Author(s):  
Dieter M. Gruen ◽  
Ian Buckley-Golder
Keyword(s):  
High Temperature ◽  
Integrated Circuits ◽  
Nuclear Power ◽  
Large Scale ◽  
Diamond Films ◽  
Chemical Vapor ◽  
Large Area ◽  
Technical Problems ◽  
Practical Applications ◽  
Single Crystal Diamond

Carbon in the form of diamond is the stuff of dreams, and the image of the diamond evokes deep and powerful emotions in humans. Following the successful synthesis of diamond by high-pressure methods in the 1950s, the startling development of the low-pressure synthesis of diamond films in the 1970s and 1980s almost immediately engendered great expectations of utility. The many remarkable properties of diamond due in part to its being the most atomically dense material in the universe (hardness, thermal conductivity, friction coefficient, transparency, etc.) could at last be put to use in a multitude of practical applications. “The holy grail”—it was realized early on—would be the development of large-area, doped, single-crystal diamond wafers for the fabrication of high-temperature, extremely fast integrated circuits leading to a revolution in computer technology.Excitement in the community of chemical-vapor-deposition (CVD) diamond researchers, funding agencies, and industrial companies ran high in expectation of early realization for many of the commercial goals that had been envisioned: tool, optical, and corrosion-resistant coatings; flat-panel displays; thermomanagement for electronic components, etc. Market projection predicting diamond-film sales in the billions of dollars by the year 2000 was commonplace. Hopes were dashed when these optimistic predictions ran up against the enormous scientific and technical problems that had to be overcome in order for those involved to fully exploit the potential of diamond. This experience is not new to the scientific community. One need only remind oneself of the hopes for cheap nuclear power or for high-temperature superconducting wires available at hardware stores to realize that the lag between scientific discoveries and their large-scale applications can be very long. Diamond films are in fact being used today in commercial applications.

Liquid nitrogen level meter for high-temperature superconductor (HTS)

2012 ◽  
Vol 19 (11) ◽  
pp. 3100-3104
Author(s):  
Heecheol Park ◽  
Hwanjun Jeong ◽  
Changyeung Lee ◽  
Purn Kim ◽  
Jangwon Cho ◽  
...  
Keyword(s):  
High Temperature ◽  
Liquid Nitrogen ◽  
High Temperature Superconductor ◽  
Nitrogen Level ◽  
Level Meter

The small spacecraft with a magnetic sail on high-temperature superconductors

2021 ◽  
pp. 130-140
Author(s):  
Timur KOMBAEV ◽  
Mikhail ARTEMOV ◽  
Valentin SYSOEV ◽  
Dmitry DEZHIN ◽  
Keyword(s):  
Magnetic Field ◽  
High Temperature ◽  
Shape Memory ◽  
New Technologies ◽  
High Temperature Superconductors ◽  
Solar Wind Plasma ◽  
Large Area ◽  
Small Spacecraft ◽  
Force Impact ◽  
Shape Memory Materials

It is proposed to develop a small spacecraft for an experiment using high-temperature superconductors (HTS) and shape memory materials. The purpose of the experiment is to test a technological capability of creating a strong magnetic field on the small spacecraft using HTS and shape memory materials for deployed large-area structures, and study the magnetic field interaction with the solar wind plasma and the resulting force impact on the small spacecraft. This article is of a polemical character and makes it possible to take a fresh look at the applicability of new technologies in space-system engineering.

Numerical Simulation of Steel Grid Structure under High Temperature

2013 ◽  
Vol 838-841 ◽  
pp. 458-461
Author(s):  
Jing Cui ◽  
Ling Feng Yin ◽  
Xiao Ming Guo ◽  
Gan Tang ◽  
Tian Jiao Jin
Keyword(s):  
Numerical Simulation ◽  
Finite Element ◽  
High Temperature ◽  
Finite Element Model ◽  
Numerical Method ◽  
Nonlinear Interaction ◽  
Element Model ◽  
Fire Tests ◽  
Grid Structure ◽  
Test Models

Based on the fire tests of WILLIAMS double-poles structure, considering the dual nonlinear interaction of material and geometric, established one complete finite element model of grid structure. For the performance that the physical and mechanics properties of steel will degrade while the temperature arising, simulate the test models with ANSYS, get a better numerical results, proof the numerical method is feasible.

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