Epilithic microbial communities, ubiquitously found in biofilms on submerged granite, limestone, and sandstone, as well as on the concrete support pillars of bridges, were examined in the Speed River, Ontario, Canada. Transmission electron microscopy showed that attached bacteria (on all substrata) were highly mineralized, ranging from Fe-rich capsular material to fine-grained (<1 mum) authigen...

Of the several species of uranium silicate minerals, sklodowskite has the most limited geographical distribution, the only recorded occurrence being that at Shinkolobwe, Katanga, Belgian Congo. It was first described by Schoep (1924a). The analogy with uranophane was recognized by Schoep (Ig24b) who subsequently (L927) described its. isomorphism with this mineral. Billiet (1936) obtained an rc-...

Submitted for the MAR11 Meeting of The American Physical Society Sorting Category: 19.1 (C) First-principles study of spin-state crossovers and hyperfine interactions of ferric iron in magnesium silicate perovskite1 HAN HSU, University of Minnesota, PETER BLAHA, TU Vienna, MATTEO COCOCCIONI, RENATA WENTZCOVITCH, University of Minnesota — The spin-state crossover in iron-bearing MgSiO3 perovskit...

The Lemoine tailings of Chibougamau, Quebec, Canada, were deposited as a pH-neutral mineral conglomerate consisting of aluminum-silicates, iron-aluminum-silicates, pyrite, chalcopyrite, and sphalerite. These tailings are colonized by an active population of Thiobacillus ferrooxidans which is localized to an acid zone occupying 40% of the tailings' surface. This population peaked at 7 x 10 most ...

A b s t r a c t The variation of silicate dissolution and crystallization rates with chemical affinity and solution composition can be quantified by the identification of the rate controlling precursor complex. The nature of this complex depends on the individual mineral structure. Specifically, the destruction of quartz and anorthite frameworks requires the breaking of only one type of structu...

This paper deals with the study of beryl, its variety, petrographic, and gemological specifications in Bahr-e-Abad area Jalalabad city. Beryl is a relatively rare silicate mineral, cyclo-silicate, chemical composition Be3Al2 (Si6O18) hexagonal crystal shape. It found igneous metamorphic rocks many parts world. In order to achieve aim this paper, three methods, namely; library work, fieldwork, l...

Consideration of the human epidemiology of diseases arising from exposure to naturally occurring and man-made mineral fibers encompasses the several forms of asbestos (chrysotile, crocidolite, amosite, anthophyllite, tremolite-actinolite), other naturally occurring silicates (talc, sepiolite, erionite, attapulgite, vermiculite, and wollastonite), and man-made mineral fibers (glass continuous fi...

Abstract Silicate minerals are widely used as green, nontoxic, low-cost materials. In this experiment, hydrophilic antifogging films of silicate were prepared by the vacuum evaporation coating method. The hydrophilicity, performance, optical properties, and surface morphology film materials analysed characterised contact angle meter, hydrothermal method, ultraviolet-visible spectrophotometer, a...