Temperature and melt composition effects on sulfate solubility in silicate melts at atmospheric pressure

Fuel composition effects on the flow-field of a lean premixed swirl-stabilized burner were studied. Methane (CH4) was enriched with hydrogen (H2) to vary the fuel composition. The burner inlet had 28-degree swirl vanes located in the annulus around a centerbody. Combustion occurred in an air-cooled quartz chamber at atmospheric pressure. The measurements were obtained, using the particle image velocimetry (PIV) technique, which allowed the 2-D velocity and vorticity fields to be examined for different fuels. The average velocity field was significantly altered, including the shape of the central and corner recirculation zones in the H2 enriched flames. The instantaneous velocity fields showed corresponding differences as well. The length scales and vorticity levels of the time-averaged velocity field differed from those for the instantaneous fields, indicating the importance of temporally resolved measurements.

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Reactions of Alkyl Halides in Fused Salt Media

Canadian Journal of Chemistry ◽

10.1139/v71-001 ◽

1971 ◽

Vol 49 (1) ◽

pp. 1-6 ◽

Cited By ~ 8

Author(s):

R. A. Bailey ◽

S. F. Prest

Keyword(s):

Organic Molecules ◽

Product Distribution ◽

Exchange Reactions ◽

Cyclization Reactions ◽

Composition Effects ◽

Carbonium Ion ◽

Product Distributions ◽

Halide Exchange ◽

Melt Composition ◽

Acid Character

Passage of C1 to C5 haloalkanes through SnCl2–KCl melts results in halide exchange reactions, alkene formation, and rearrangement (including cyclization) reactions of the organic molecules. Relative reactivities, product distributions and melt composition effects are consistent with a carbonium ion mechanism in which the melt functions as a halide ion acceptor. Some control of product distribution by choice of Lewis acid character of the melt seems possible.

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Dynamic viscosity of some silicate melts to 1688°C under atmospheric pressure

Thermochimica Acta ◽

10.1016/0040-6031(80)80040-2 ◽

1980 ◽

Vol 37 (2) ◽

pp. 189-195 ◽

Cited By ~ 4

Author(s):

A.J. Piwinskii ◽

H.C. Weed

Keyword(s):

Dynamic Viscosity ◽

Atmospheric Pressure ◽

Silicate Melts

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Convective fractionation during magnetite and hematite dissolution in silicate melts

Mineralogical Magazine ◽

10.1180/minmag.1993.057.388.09 ◽

1993 ◽

Vol 57 (388) ◽

pp. 469-488 ◽

Cited By ~ 2

Author(s):

C. H. Donaldson

Keyword(s):

Single Crystals ◽

Atmospheric Pressure ◽

Electron Probe ◽

Silicate Melts ◽

Magmatic Differentiation ◽

Melt Viscosity ◽

Electron Probe Analysis ◽

Continuous Release ◽

Fe Content ◽

Dissolved Matter

AbstractSingle crystals of magnetite and of hematite have been dissolved at atmospheric pressure in superheated melts in the systems CaO-MgO-Al2O3-SiO2 and CaO-Al2O3-SiO2, and in a basalt. The crystals were suspended in alumina crucibles containing ca 3.5 cm 3 of melt. Quenched run products were examined optically and by electron probe analysis to establish the distribution of Fe in the glassy charges. There is usually a concentration of Fe at the base of a run product, consistent with flow of dissolved matter from the crystal to the floor. One or more columns of brown, Fe-rich glass may extend from the underside of a relic crystal towards the floor. In CMAS run products, such columns typically extend this entire distance, whereas in the CAS and basalt run products, the columns are either detached from the crystal or do not reach the floor. In the CMAS melt (viscosity ~1 poise) there is apparently continuous release of Fe-bearing melt from around a dissolving crystal, whereas in the CAS and basalt melts (viscosities 7000 and 300 poise, respectively) release is intermittent. In CMAS run products the Fe content is usually greatest, in glass, at the base, and declines gradually upwards; in CAS and basalt runs the bottom of a crucible is occupied by discrete, sharply bounded pillows of Fetich glass, with only slight, or no, gradation in composition. Rising gas bubbles can elevate small blobs of the denser, Fe-bearing melt from around a dissolving crystal, and trains of bubbles in the CAS melt may guide this Fe-bearing melt, against gravity, to the surface of the charge. When the bubbles burst at the surface, this dense melt is left in an unstable location and releases diapirs which descend to the bottom of the crucible. In spite of the evidence that convective fractionation occurs in these haplomagmas and in the basalt, it remains to be demonstrated that it will occur during sidewall crystallization or during the growth of minerals in a cumulus mush to cause magmatic differentiation.

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