Measurement of Vapor Pressures of Selected PBDEs, Hexabromobenzene, and 1,2-Bis(2,4,6-tribromophenoxy)ethane at Elevated Temperatures

2013 ◽  
Vol 59 (1) ◽  
pp. 8-15 ◽  
Author(s):  
Hidetoshi Kuramochi ◽  
Hidetaka Takigami ◽  
Martin Scheringer ◽  
Shin-ichi Sakai
Keyword(s):  
Elevated Temperatures ◽  
Vapor Pressures

EXPERIMENTAL INVESTIGATION OF CHALCOCITE: ANNEALING AND PLASTIC DEFORMATION AT ELEVATED TEMPERATURES

1965 ◽  
Vol 2 (2) ◽  
pp. 98-117
Author(s):  
Raymond Davies
Keyword(s):  
Experimental Investigation ◽  
Plastic Deformation ◽  
Solid State ◽  
Grain Growth ◽  
Annealing Time ◽  
Silica Glass ◽  
Elevated Temperatures ◽  
Recrystallization Behavior ◽  
Vapor Pressures ◽  
Sulfur Vapor

The recrystallization behavior and deformation of synthetic chalcocite (Cu2S) in the temperature range 400–725 °C was studied microscopically after the compound was annealed in evacuated silica glass capsules and heated under differential pressures in sealed gold capsules. The temperature of recrystallization and grain growth ascribed to the hexagonal cubic inversion, at sulfur vapor pressures much less than 1 atmosphere, was determined at 465 ± 5 °C, with annealing time of [Formula: see text].Experiments involving differential pressures of 8 000 p.s.i. show that chalcocite in the solid state becomes considerably more mobile above 563 ± 10 °C and can readily be injected as a plastic mass to form veins without preservation of deformational textures.Natural bornite and natural galena may also be injected under differential pressure at 640 °C, but some unhealed fractures remain. Flow structure is well-preserved in galena and, under certain conditions, in bornite.Mixtures of bornite and pyrite flowed and recrystallized to chalcopyrite and bornite with exsolved chalcopyrite. No evidence of flowage remained.Chalcopyrite and pyrrhotite are resistant to injection under similar differential pressures and temperatures.

scholarly journals Vaporization Enthalpies and Vapor Pressures of the Major Components of Opopanax Oil, α-Santalene, cis α Bisabolene, cis α-Bergamotene,

2021 ◽  
Author(s):  
Dustin Barton ◽  
James S Chickos
Keyword(s):  
Gas Chromatography ◽  
Vapor Pressure ◽  
Elevated Temperatures ◽  
Vapor Pressures ◽  
Polycyclic Hydrocarbons ◽  
Ambient Temperatures ◽  
Correlation Gas Chromatography ◽  
Existing Data

Abstract The vapor pressures and vaporization enthalpies of the major components of opopanax oil, a medicinal that has been in use since biblical times, are evaluated by correlation gas chromatography. Two sets of hydrocarbon standards are used, n-alkanes and a mixture of cyclic and polycyclic hydrocarbons. Two of the oil’s sesquiterpene components, evaluated in a previous study, were used both as standards and also as targets. Their use as targets was in an effort to confirm both their identity in the oil and the reproducibility of their properties. All correlations produce reproducible vaporization enthalpies and vapor pressures at ambient temperatures. At elevated temperatures, the use of the two different sets of standards resulted in some divergence in vapor pressure. Experiments are described aimed at attenuating this divergence. The results are compared to existing data.

Microstructural Development in Nano-Crystalline Zinc Sulfide Powders

1992 ◽  
Vol 286 ◽  
Author(s):  
Y. Han ◽  
E.T. Voiles ◽  
L.S. Chumbley ◽  
M. Akinc
Keyword(s):  
Zinc Sulfide ◽  
Elevated Temperatures ◽  
Ambient Pressure ◽  
Microstructural Development ◽  
Vapor Pressures ◽  
Electron Microscopic ◽  
Nano Crystalline ◽  
High Vapor ◽  
The Individual ◽  
Individual Particles

ABSTRACTMonodispersed, spherical, submicron size zinc sulfide powders were previously prepared in our laboratory utilizing homogeneous precipitation by thermal decomposition of thioacetamide in acidic aqueous solutions. Electron microscopic investigations of these powders indicated that the individual particles were agglomerates of 8∼14 nm size crystallites. It has been known that zinc sulfide does not sinter under ambient pressure due to the covalent nature of its bonding, high melting point, and relatively high vapor pressures at elevated temperatures. The heat treatment of these nano-crystalline zinc sulfide powders, however, showed some degree of sintering at temperatures as low as 600°C under vacuum.

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