Phase formation of Mn-doped zinc silicate in water at high-temperatures and high-pressures

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.

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Sound velocities measurement on MgSiO3 akimotoite at high pressures and high temperatures with simultaneous in situ X-ray diffraction and ultrasonic study

Physics of The Earth and Planetary Interiors ◽

10.1016/j.pepi.2013.06.005 ◽

2014 ◽

Vol 228 ◽

pp. 97-105 ◽

Cited By ~ 10

Author(s):

Chunyin Zhou ◽

Steeve Gréaux ◽

Norimasa Nishiyama ◽

Tetsuo Irifune ◽

Yuji Higo

Keyword(s):

High Temperatures ◽

High Pressures ◽

X Ray Diffraction ◽

X Ray ◽

Ultrasonic Study ◽

Sound Velocities

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Slow Strain Rate Testing of Ti-6Al-4V Alloy in Hydrogen Gas at High Pressures and High Temperatures

MATERIALS TRANSACTIONS ◽

10.2320/matertrans.m2017031 ◽

2017 ◽

Vol 58 (6) ◽

pp. 886-891 ◽

Cited By ~ 2

Author(s):

Kenichi Koide ◽

Toshirou Anraku ◽

Akihiro Iwase ◽

Hiroyuki Inoue

Keyword(s):

Strain Rate ◽

High Temperatures ◽

High Pressures ◽

Hydrogen Gas ◽

Slow Strain Rate ◽

Slow Strain Rate Testing ◽

Rate Testing

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Structure of Liquid Metals at High Temperatures and High Pressures: Studied by ab initio Molecular-Dynamics Simulations

The Review of High Pressure Science and Technology ◽

10.4131/jshpreview.18.343 ◽

2008 ◽

Vol 18 (4) ◽

pp. 343-350

Author(s):

Kozo HOSHINO

Keyword(s):

Molecular Dynamics ◽

Ab Initio ◽

Molecular Dynamics Simulations ◽

High Temperatures ◽

High Pressures ◽

Liquid Metals ◽

Dynamics Simulations ◽

Structure Of Liquid

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Effects of hydrogen on the microstructure and microchemistry of Ti3Al – Nb intermetallics at high temperatures and high pressures

Journal of Materials Research ◽

10.1557/jmr.1996.0278 ◽

1996 ◽

Vol 11 (9) ◽

pp. 2186-2197 ◽

Cited By ~ 5

Author(s):

H. Z. Xiao ◽

I. M. Robertson ◽

H. K. Birnbaum

Keyword(s):

Solid Solution ◽

High Temperatures ◽

High Pressures ◽

Chemical Potential ◽

Substitutional Solid Solution ◽

Hydrogen Gas ◽

Solid Solution Phase ◽

Face Centered Cubic ◽

Fine Grained ◽

Surrounding Matrix

The microstructural and microchemical changes produced in a Ti–25Al–10Nb–3V–1Mo alloy (at. %) by charging at high temperatures in high pressures of hydrogen gas have been studied using transmission electron microscopy (TEM) and x-ray methods. Hydrides incorporating all of the substitutional solutes that formed during charging have a face-centered cubic (fcc) structure and exhibit either a plate or fine-grained morphology. With increasing hydrogen content, the size of the hydrides decreases and their microchemistry changes as they approach the stable binary hydride, TiH2. Rejection of substitutional solute elements from the hydride produces changes in the microchemistry, and consequently in the crystal structure, of the surrounding matrix. In alloys containing 50 at. % H, this solute redistribution results in the formation of an orthohombic substitutional solid solution phase containing increased levels of Nb. The driving force of this redistribution of solutes is the reduction in the chemical potential of the system as the amount of the most stable hydride, TiH2, forms. The hydrides reverted to a solid solution on annealing in vacuum at 1073 K, and the original microchemistry of the alloy was restored. Reversion from the hydride structure to the original α2 ordered DO19 structure proceeds via a disordered HCP phase.

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