We report infrared multiple photon dissociation spectra of cryogenically-cooled (NaSO4(-))2(H2O)n dianions (n = 0-6, 8) in the spectral range of the sulfate stretching and bending modes (580-1750 cm(-1)). Characteristic absorption bands and structural trends are identified based on a comparison to harmonic spectra of minimum-energy structures. The bare quarternary complex (NaSO4(-))2 exhibits a...

R ECENTLY a new reagent was proposed for the determination of cholesterol (1, 2). This reagent was purported to be saturated ferrous sulfate in glacial acetic acid. Since it has been reported that ferrous sulfate is qualitatively insoluble in anhydrous acetic acid (3, 4) and that ferrous iron is “subject to pronounced air oxidation in glacial acetic acid” (5), it was felt that several factors s...

Improved and unimproved roads can be the primary source of stream sediment in forested watersheds . We assessed dif ferences in product ion of to ta l suspended solia!s (TSS; ppm) f rom four road sulfate condit ions in a Southern Appalachian watershed: (1) a 2-yr-oldpaved surface (P) , (2) an improvedgravel sulfate with control leddrainage and rout ine maintenance (RG), (3) an improvedgravel su...

An integrated bioleaching system (stable pH-silver ion-chloride ion) was firstly proposed to for improving the efficiency of chalcopyrite bioleaching by mixed strains of Acidithiobacillus. The individual effects of stable pH, silver ion, and chloride ion on bioleaching were respectively studied. The highest copper ion concentrations in each system were 45.8, 50.2, and 45.2 mg/l, respectively, w...

Specific activation of amino acids by aminoacyl-tRNA synthetases is essential for maintaining translational fidelity. Here, we present crystal structures of Saccharomyces cerevisiae tryptophanyl-tRNA synthetase (sTrpRS) in apo form and in complexes with various ligands. In each complex, there is a sulfate ion bound at the active site which mimics the alpha- or beta-phosphate group of ATP during...

Proteodermatan sulfate was extracted from four areas of the bovine gastrointestinal tract (esophagus, stomach, small intestine and colon) with 4 M guanidine-HCl and then purified by ion-exchange and gel filtration chromatography. Dermatan sulfate chains which made up proteodermatan sulfate from each area were separately prepared by Pronase P and endo-beta-xylosidase digestion. The properties of...

A new analytical methodology for a simple and efficient on-line preconcentration of trace inorganic anions in water and salt samples prior to ion chromatographic determination is proposed. The preconcentration method is based on partition/ion-exclusion chromatographic ion stacking (PIEC ion stacking) with a hydrophilic polymer gel column containing a small amount of fixed anionic charges. The d...

a simple analytical system suitable for nephelometric measurements is introduced in this article. the electronic and optical components are simplified so that the apparatus is easily assembled from materials that are generally available. this instrument is designed for the efficient measurement of anions, and microgram quantities of ions may be determined by a convenient method of titration. us...