A structural refinement of a natural sample of a Co-bearing mansfieldite, AlAsO(4)·2H(2)O [aluminium orthoarsenate(V) dihydrate], has been performed based on synchrotron powder diffraction data, with 5% of the octa-hedral Al sites replaced by Co. Mansfieldite is the aluminium analogue and an isotype of the mineral scorodite (FeAsO(4)·2H(2)O), with which it forms a solid solution. The framework ...

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,...

An effect of promoters such as calcium, aluminium, and potassium oxides and also addition of chromium and manganese on the structure of cobalt catalysts was examined. Studies of the catalytic ammonia decomposition over the cobalt catalysts are presented. The studies of the ammonia decomposition were carried out for various ammonia-hydrogen mixtures in which ammonia concentration varied in the r...

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...

In this talk, I will discuss results from our group in the area of computational modeling using density functional theory for reversible hydrogen storage materials. The reversible hydrogen storage is an important area in the context of renewable energy and the reversibility places important challenge. We have studied doped magnesium hydrides as well as decorated metal organic frameworks (MOF). ...

The centrosymmetric crystal structure of the novel semi-organic compound, 3C(3)H(5)N(2)S(+)·HSO(4) (-)·SO(4) (2-)·H(2)O, is based on chains of alternating anions and water mol-ecules (formed by O-H⋯O hydrogen bonds). The chains are inter-connected with the 2-amino-1,3-thia-zolium cations via strong N-H⋯O and weak C-H⋯O hydrogen-bonding inter-actions into a three-dimensional network.

The structure of synthetic disodium magnesium disulfate decahydrate at 180 K consists of alternating layers of water-coordinated [Mg(H(2)O)(6)](2+) octahedra and [Na(2)(SO(4))(2)(H(2)O)(4)](2-) sheets, parallel to [100]. The [Mg(H(2)O)(6)](2+) octahedra are joined to one another by a single hydrogen bond, the other hydrogen bonds being involved in inter-layer linkage. The Mg(2+) cation occupies...

The involvement of the ascorbate (AsA) system in the response of pumpkin (Cucurbita pepo L.) roots to aluminium stress was studied. The treatment of 5-day-old pumpkin seedlings with 50 microM aluminium sulphate resulted in approximately 60% inhibition of root growth within 48-60 h of treatment, while aluminium accumulated in the roots reaching a maximum within 48h. During the same period, the h...