Non-equilibrium synthesis of new materials

R. W. Gardiner; P. S. Goodwin; S. B. Dodd; B. W. Viney

doi:10.1007/bf00136796

Towards Catalysts Prepared by Cold Plasma

Catalysts ◽

10.3390/catal12010075 ◽

2022 ◽

Vol 12 (1) ◽

pp. 75

Author(s):

Jacek Tyczkowski ◽

Hanna Kierzkowska-Pawlak

Keyword(s):

Plasma Treatment ◽

Cold Plasma ◽

Plasma Deposition ◽

New Materials ◽

Treatment Methods ◽

Equilibrium Plasma ◽

Plasma Techniques ◽

Non Equilibrium

Cold (non-equilibrium) plasma techniques have long been used as plasma deposition methods to create new materials, often with unique properties, which cannot be produced any other way, as well as plasma treatment methods for the sophisticated modification of conventional materials [...]

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Thermal transport properties in GaAs (110)/GaAs (100) and GaAs/InAs interfaces by Reverse Non-equilibrium Molecular Dynamics

Journal of Applied Sciences and Environmental Management ◽

10.4314/jasem.v23i10.21 ◽

2019 ◽

Vol 23 (10) ◽

pp. 1901-1906

Author(s):

O.N. Nenuwe ◽

O.E. Agbalagba

Keyword(s):

Molecular Dynamics ◽

Thermal Resistance ◽

Thermal Management ◽

Electronic Device ◽

New Materials ◽

Thermal Interface ◽

Dynamic Studies ◽

Thermal Interface Resistance ◽

Non Equilibrium Molecular Dynamics ◽

Non Equilibrium

It is well known that the physics of thermal management is quite challenging as electronic device sizes are miniaturized and new materials are developed. This study calculates the thermal interface conductance (TIC), thermal interface resistance (TIR) and thermal grain conductivity across GaAs(110)/GaAs(100) and GaAs/InAs interfaces using the reverse non-equilibrium molecular dynamics (RNEMD) technique. Data obtained showed that, at GaAs(110)/GaAs(100) the TIC increased from 0.912 x 10-9 (W/K) to 1.433 x 10-9 (W/K), the TIR decreased from 1.096 x 109 (K/W) to 0.697 x 109 (K/W) between 300 K and 1000 K, and the thermal grain conductivity increased from 7.47 (W/mK) to 15.52 (W/mK) and 7.48 (W/mK) to 80.71 (W/mK) between 15 Å and 55 Å at 300 K. At GaAs/InAs interface the TIC increased from 7.228 x -10 (W/K) to 14.498 x 10-10 (W/K) and the TIR decreased from 0.138 x 1010 (K/W) to 0.068 x 1010 (K/W) between 300 K and 700 K, respectively. It was observed that, as temperature is increased the TIC and TIR for both materials change significantly. This trend is consistent with previous molecular dynamic studies of interface materials.Keywords: Interface conductance, thermal resistance, grain conductivity, temperature.

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New Materials: Non‐Equilibrium Synthesis by Laser

Journal of Laser Applications ◽

10.2351/1.4745227 ◽

1989 ◽

Vol 1 (2) ◽

pp. 27-42 ◽

Cited By ~ 8

Author(s):

J. Mazumder ◽

S. Sircar ◽

C. Ribaudo ◽

A. Kar

Keyword(s):

New Materials ◽

Non Equilibrium

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A new type of defect structure in 124-superconducting oxide revealed by HREM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100089779 ◽

1991 ◽

Vol 49 ◽

pp. 1092-1093

Author(s):

R. Sharma ◽

B.L. Ramakrishna ◽

N.N. Thadhani ◽

D. Hianes ◽

Z. Iqbal

Keyword(s):

Shock Wave ◽

Defect Structure ◽

Neutron Radiation ◽

Weak Links ◽

Defect Structures ◽

New Materials ◽

New Type ◽

Current Densities ◽

Processing Techniques ◽

Microstructural Studies

After materials with superconducting temperatures higher than liquid nitrogen have been prepared, more emphasis has been on increasing the current densities (Jc) of high Tc superconductors than finding new materials with higher transition temperatures. Different processing techniques i.e thin films, shock wave processing, neutron radiation etc. have been applied in order to increase Jc. Microstructural studies of compounds thus prepared have shown either a decrease in gram boundaries that act as weak-links or increase in defect structure that act as flux-pinning centers. We have studied shock wave synthesized Tl-Ba-Cu-O and shock wave processed Y-123 superconductors with somewhat different properties compared to those prepared by solid-state reaction. Here we report the defect structures observed in the shock-processed Y-124 superconductors.

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Application of analytical electron microscopy to studies of equilibrium and non-equilibrium segregation in materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130705 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1214-1215

Author(s):

Edward A Kenik

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Extended Defects ◽

Probe Diameter ◽

Specimen Holder ◽

Analytical Electron ◽

Scanning Transmission ◽

Solute Atoms ◽

Equilibrium Segregation ◽

Non Equilibrium

Segregation of solute atoms to grain boundaries, dislocations, and other extended defects can occur under thermal equilibrium or non-equilibrium conditions, such as quenching, irradiation, or precipitation. Generally, equilibrium segregation is narrow (near monolayer coverage at planar defects), whereas non-equilibrium segregation exhibits profiles of larger spatial extent, associated with diffusion of point defects or solute atoms. Analytical electron microscopy provides tools both to measure the segregation and to characterize the defect at which the segregation occurs. This is especially true of instruments that can achieve fine (<2 nm width), high current probes and as such, provide high spatial resolution analysis and characterization capability. Analysis was performed in a Philips EM400T/FEG operated in the scanning transmission mode with a probe diameter of <2 nm (FWTM). The instrument is equipped with EDAX 9100/70 energy dispersive X-ray spectrometry (EDXS) and Gatan 666 parallel detection electron energy loss spectrometry (PEELS) systems. A double-tilt, liquid-nitrogen-cooled specimen holder was employed for microanalysis in order to minimize contamination under the focussed spot.

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