The measurement of sulfide, especially hydrogen sulfide, has held the attention of the analytical community due to its unique physiological and pathophysiological roles in biological systems. Electrochemical detection offers a rapid, highly sensitive, affordable, simple, and real-time technique to measure hydrogen sulfide concentration, which has been a well-documented and reliable method. This...

Recent advances in nanotechnology could facilitate the production of cheaper solar cells. This review describes synthetic routes to various nanostructured materials that are potentially useful in photovoltaic applications. We have focused on materials that are based on earth abundant elements and/or those that are held to have lower toxicity. Methods to synthesize binary chalcogenides with vari...

ABSTRACT Most of the World's platinum-group element ore deposits occur as thin stratiform layers within layered intrusions. These generally contain disseminated base-metal sulfides or chromite. However, cryptic also without chromite in what are known low-S-high deposits. The origin these is not clearly understood. Luanga Complex hosts largest elements resource South America (i.e., 142 Mt at 1.2...

Electrodeposition has been widely used for the low-cost formation of large-area thin films of various crystalline materials. In this work, we use thermodynamic calculations to guide electrochemical experiments, in which we conduct a systematic investigation of crystalline iron sulfides formation on electrically poised iron substrates in H2S aqueous solutions. Whereas thermodynamic calculations ...

More than half a century ago, Irish physicist John Desmond Bernal and Swiss geochemist Victor M. Goldschmidt independently proposed that clay minerals may have played an important role in prebiotic synthesis (Bernal 1949; Goldschmidt 1952). I concur that mineral catalysis must have had a central role in prebiotic synthesis because most uncatalyzed reactions start from simple precursors like hyd...

Formation constants for thioarsenite species have been determined in dilute solutions at 25 uC, SH2S from 10 to 10 M, SAs from 10 to 10 M, and pH 7 and 10. The principal inorganic arsenic species in anoxic aquatic systems are arsenite, As(OH)3 , and a mononuclear thioarsenite with an S/As ratio of 3 : 1. Thioarsenic species with S/As ratios of 1 : 1, 2 : 1, and 4 : 1 are lesser components in su...

Iron (Fe) cycling exerts strong control on the mobility and bioavailability of key nutrient phosphate (PO4) in soils sediments. Coprecipitation PO4 is known to alter structure Fe (oxyhydr)oxides (FeOx), however environmental fate PO4-bearing FeOx not well-understood. Here, with 9 mol% coprecipitated were prepared by Fe(III) hydrolysis Fe(II) oxidation presence dissolved PO4, addition pure synth...

Sulfide mineral dissolution is an important reaction controlling geochemical and environmental chemical processes in aqueous environments. In this study, we quantitatively evaluated the kinetic influence of galvanic interactions between different sulfide minerals on their seawater. Four hydrothermal sulfides with amounts Fe disulfide (pyrite) were reacted artificial seawater for 144 h, rates Zn...

Kinetics and stoichiometry of aerobic chemical and biological sulfide oxidation in wastewater from sewer networks were studied. In this respect, the effects of temperature and pH were investigated in the ranges 10 to 20 degrees C and 5 to 9, respectively. The temperature dependency of sulfide oxidation kinetics was described using an Arrhenius relationship. The effect of pH on the rate of chemi...

The hemoglobin of the deep-sea hydrothermal vent vestimentiferan Riftia pachyptila (annelid) is able to bind toxic hydrogen sulfide (H(2)S) to free cysteine residues and to transport it to fuel endosymbiotic sulfide-oxidising bacteria. The cysteine residues are conserved key amino acids in annelid globins living in sulfide-rich environments, but are absent in annelid globins from sulfide-free e...