In wetland soils and underwater sediments of marine, brackish and freshwater systems, the strong phytotoxin sulfide may accumulate as a result of microbial reduction of sulfate during anaerobiosis, its level depending on prevailing edaphic conditions. In this review, we compare an extensive body of literature on phytotoxic effects of this reduced sulfur compound in different ecosystem types, an...

We report transient absorption saturation measurements on lead sulfide colloidal nanocrystals at the first and second exciton energies and fit the results to a model incorporating intraband and interband relaxation processes. We study in detail the Auger recombination from the first excited state, which takes place when more than one electron-hole pair is excited in a dot. We find an Auger coef...

Major terrestrial reservoirs have Pb isotopes more radiogenic than the bulk silicate Earth. This requires a missing unradiogenic Pb reservoir, which has been argued to reside in the lower continental crust or dissolved in the core. Chalcophile element studies indicate that continent formation requires the formation of sulfide-bearing mafic cumulates in arcs. Because Pb, but not U, partitions in...

Hydrogen sulfide (H2S) produced by commensal sulfate-reducing bacteria, which are often members of normal colonic microbiota, represents an environmental insult to the intestinal epithelium potentially contributing to chronic intestinal disorders that are dependent on gene-environment interactions. For example, epidemiologic studies reveal either persistent sulfate-reducing bacteria colonizatio...

Kligler and Triple Sugar Iron (TSI) media have been considered to be interchangeable for the purpose of detecting hydrogen sulfide production in the family Enterobacteriaceae. Contrary evidence is presented in this report. From various sources, 11 cultures were isolated which yielded a positive hydrogen sulfide reaction on Kligler medium and a negative reaction on TSI. Biochemically, these cult...

Sulfide ores play an extremely important role in the development of mineral resource base Russia, as a source rare, non-ferrous, and precious metals. However, sulfide ore deposits is associated with risk dust explosions, oxidative processes that lead to spontaneous combustion ores. The article substantiates urgency solving problem reducing risks taking into account changes balance gold-sulfide ...

The evolution of the martian core is widely assumed to mirror the characteristics observed for Earth's core. Data from experiments performed on iron-sulfur and iron-nickel-sulfur systems at pressures corresponding to the center of Mars indicate that its core is presently completely liquid and that it will not form an outwardly crystallizing iron-rich inner core, as does Earth. Instead, planetar...

Metal sulfide dielectric thin films have been deposited using dynamic wet chemistry processing on silver coated hollow glass waveguides (HGWs). The sulfides used were cadmium sulfide (CdS) and lead sulfide (PbS); both films have excellent infrared transparency and high refractive index contrast. The thickness of these thin films can be tailored to minimize the attenuation of the HGW over specif...