an efficient, mild and environmentally friendly method was reported for the synthesis of an efficient, mild and environmentally friendly method was reported for the synthesis of pyranopyroles from aryl aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate in the presence of catalytic amounts of methyl imidazolium hydrogen sulfate ([hmim][hso4]) as an efficient catalyst. these synth...

THE ASYMMETRIC UNIT OF THE TITLE COMPOUND [SYSTEMATIC NAME: (R,R)-2,4-bis-(4-hydroxy-phen-yl)-N,N'-dimethyl-3-oxapentane-1,5-diammonium bis-(hydrogen sulfate)], C(18)H(26)N(2)O(3) (2+)·2HSO(4) (-), contains one half-cation and one hydrogen sulfate anion. The cation has crystallographically imposed twofold symmetry with the rotation axis passing through the central ether O atom. Hydrogen bonds b...

The discovery of hydrogen-rich waters preserved below the Earth's surface in Precambrian rocks worldwide expands our understanding of the habitability of the terrestrial subsurface. Many deep microbial ecosystems in these waters survive by coupling hydrogen oxidation to sulfate reduction. Hydrogen originates from water-rock reactions including serpentinization and radiolytic decomposition of wa...

Ionic liquids based on 1-alkyl-3-methylimidazolium cations and the hydrogen sulfate (or bisulfate) anion, HSO(4)(-), are much more viscous than ionic liquids with alkyl sulfates, RSO(4)(-). The structural origin of the high viscosity of HSO(4)(-) ionic liquids is unraveled from detailed comparison of the anion Raman bands in 1-ethyl-3-methylimidazolium hydrogen sulfate and 1-butyl-3-methylimida...

The cations and anions of the title salt, 3C(6)H(16)N(+)·HSO(4) (-)·SO(4) (2-), are linked by N-H⋯O and O-H⋯O hydrogen bonds into a three-dimensional network. The hydrogensulfate ion, with a single S-O(H) bond of 1.563 (2) Å, forms a short O-H⋯O hydrogen bond [O⋯O = 2.609 (2) Å] to the sulfate ion. The hydrogensulfate ion accepts two hydrogen bonds from two cations, whereas the sulfate ion, as ...

In this study, oxidation of some 3,5-diacyl or 3,5-diester 1,4-dihydropyridines to corresponding pyridine derivatives using sodium bromate in the presence of NH4Cl, NaHSO4 and Bu4NHSO4 under thermal conditions has been investigated. The yield and structure of formed products is similar under all conditions; however, the reaction is accelerated in the presence of Bu4NHSO4 and NaHSO4. In addition...

The anion-binding properties of two tripodal-based hexaureas appended with the m-nitrophenyl (1) and pentafluorophenyl (2) groups have been studied both experimentally and theoretically, showing strong affinities for sulfate over other inorganic oxoanions such as hydrogen sulfate, dihydrogen phosphate, bicarbonate, nitrate, and perchlorate. The structural analysis of the sulfate complex with 1 ...

oil exploration and production zones are very frequently contaminated with petroleum hydrocarbons or its derivatives. the most important exploration and production zones are located in south-west and south of the country, in iran. masjed soleiman city is located on an oil field. the soil of this region has been affected by the petroleum composition. mach petroleum seepages and springs (asphalt,...

BACKGROUND We studied the annual variability of the concentration and isotopic composition of main sulfur species and sulfide oxidation intermediates in the water column of monomictic fresh-water Lake Kinneret. Sulfate concentrations in the lake are <1 mM and similar to concentrations that are proposed to have existed in the Paleoproterozoic ocean. The main goal of this research was to explore ...

The metabolism of Desulphovibrio desulphuricans does not appear to have been studied extensively. Stephenson and Stickland (1931) and Sisler and ZoBell (1950) showed that the organism can use gaseous hydrogen as a reducing agent for sulfate reduction. By growing cultures for several generations in mineral salt solution containing less than one part per million of sulfate, Sisler and ZoBell (195...