Sulfur texture

Figure 18. Cross section and exterior (top) surface of massive sulfur texture in high-temperature coating allowed to cool slowly...

The results of this study have shown that the physical appearance of sulfur textures in spray coating can be quite variable and that this variation can be correlated with the performance of the coating in controlling the release of nitrogen from a soluble fertilizer. These examinations also... 

The polyamides are soluble in high strength sulfuric acid or in mixtures of hexamethylphosphoramide, /V, /V- dim ethyl acetam i de and LiCl. In the latter, compHcated relationships exist between solvent composition and the temperature at which the Hquid crystal phase forms. The polyamide solutions show an abmpt decrease in viscosity which is characteristic of mesophase formation when a critical volume fraction of polymer ( ) is exceeded. The viscosity may decrease, however, in the Hquid crystal phase if the molecular ordering allows the rod-shaped entities to gHde past one another more easily despite the higher concentration. The Hquid crystal phase is optically anisotropic and the texture is nematic. The nematic texture can be transformed to a chiral nematic texture by adding chiral species as a dopant or incorporating a chiral unit in the main chain as a copolymer (30). 

The remaining tailings left over from the clay fractionation step is either flocculated with alum, high molecular weight polymers, or a weak (pH 3.0) solution of sulfuric acid, and stored in settling ponds as waste, or may be filtered and sold to the brick industry as a coating material. It also may be dried and sold as a filler in plastics and textured paint (qv). 

The difference in mineralogy of the Kuroko and present-day back-arc deposits are (1) metastable phases such as native sulfur, wurtzite, and amorphous silica are poor in the Kuroko deposits (2) arsenic minerals such as jordanite, tetrahedrite-tennantite, native arsenic, and realgar are common in the present day back-arc deposits (Okinawa Myojinsho Knoll Caldera), but rare in Kuroko deposits except tetrahedrite-tennantite (3) secondary minerals such as cerussite and covellite are common in present day back-arc deposits (e.g., Okinawa, Myojinsho Knoll Caldera) (4) Dendritic texture is common in the present day back-arc deposits. 

Mineral tanning was probably first practiced in ancient Mesopotamia and then spread to Egypt, the Middle East, and the Mediterranean Sea area (Levey 1958). Mineral-tanned leather is soft to handle, has a velvety texture, and is almost white, a color practically impossible to achieve by other tanning processes. It is, however, very sensitive to humidity and water under wet conditions the alum in the leather is hydrolyzed (decomposed by water), forming sulfuric acid, a very strong acid that attacks the leather and causes its rapid decay. Mineral-tanned leather that has been humid or wet for a more or less extended period of time loses some of its characteristic properties, such as softness, pliability, and strength, and becomes hard, horny, and brittle. 

The dependence of adsorption properties and texture on electrolytic palladium deposits on the deposition potential was investigated by Tsirlina et al. [116]. It was found that, in sulfuric acid solutions, the palladium dissolution, which accompanies the oxygen adsorption, obscures the adsorption behavior of the deposits with respect to oxygen. Assumptions were made about the predominant crystallographic orientation (100) of the surface of some palladium deposits being dependent on the deposition potential and about the presence of regions whose adsorption properties are anomalous with respect to copper. The assumptions are based on a comparative analysis of the copper adsorption data and x-ray diffraction patterns. In addition to sites of crystalline palladium, the deposits were found to have disordered areas as well. 

Limestones vary greatly in color and texture, the latter ranging front dense and hard limestone, e.g.. marble or travertine, which can be suwed and polished, to soft, friable forms, e.g., chalk and marl. Chalk is a very fine-grained white limestone, while marl is an impure deposition product that contains clay and sand. Texture, hardness, and porosity appear to be functions of the degree of cementation and consolidation during the formation of these materials. Color variations arise from the presence of impurities. Some impurities, such as sulfur and phosphorus, make limestone unattractive for metallurgical uses. 

The polyamides are soluble in high sirength sulfuric acid or in mixtures of hexamelhylphosphoiamide. AMV-diinethylaeciamidc. and l.ifT. The liquid-crystal phase is optically anisotropic and the texture is nematic. The nematic texture can he transformed lo a chiral nematic texture by adding chiral species us a dopant or incorporating a chiral unit in the main chain as a copolymer. 

Scanning electron micrographs (SEM) of bioleached shale, which has been leached with the acid produced by sulfur-oxidizing bacteria, have revealed a pitted, spongy-appearing surface texture. Bioleaching removes primarily the carbonate minerals, such as dolomite and calcite, which are apparently deposited in pits throughout the rest of the mineral matrix. The removal of the carbonate would be expected to increase the porosity of the raw shale. Since the results of SEM reveal only the surface... 

Sampling. Two sets of vibracores were collected at each site. A previously collected set was used, along with other cores in each area, to determine stratigraphic and sedimentologic relationships. Color, texture, and structure were used to establish different lithofacies, which were later verified or modified using x-ray radiography. Ash and total sulfur contents were then determined for channel samples of these units. 

There was no loss in flavorant at a 100 mg level when either whole soy or soy 7S protein was used, but there was a 14-24 percentage loss when 11S protein was used. Only soy 11S protein affected the substituted pyrazine content of the mixture at all addition levels. The higher the substituted pyrazine congener, the smaller was the percentage loss with any of the protein types. At the 500 mg level, only about 50% of the amount of any of the methyl pyrazines in the control was recovered from either soy 7S or 11S protein while 70% was recovered from whole soy protein. These results greatly extend the initial work reported by Palkert and Fagerson (11J who determined that about 75% of dimethyl thiazole, a sulfur-nitrogen heterocycle, was recovered from dry, textured soy protein. 

Bottcher, M.E., and Lepland, A. (2000) Biogeochemistry of sulfur in a sediment core from the west-central Baltic Sea evidence from stable isotopes and pyrite textures. J. Mar. Syst. 25, 299-312. 

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