We examined the effects of hypoxia and sulphide levels on the ventilatory activity of Arenicola marina and determined whether ventilation compensates for oxygen deficiency and affects the mode of energy provision. A. marina ventilated intermittently, irrespective of ambient P(O2) and sulphide concentration. The ventilation rate was 28.5+/-16 ml h(-1) g(-1) wet mass during normoxia, but increase...

This study encompasses the ore mineralogy, textures and sulphide trace element chemistry of Palaeoproterozoic Lovisa stratiform Zn-Pb deposit stratigraphically underlying Fe Formation in Bergslagen province (Sweden). We investigate relative timing formation subsequent modifications its ores relation to c. 1.87–1.80 Ga Svecokarelian orogeny. The consists several different types. massive sphaleri...

The product of the biological sulphate reduction is sulphide. High concentrations of molecular H2S (g) can be inhibitory for microbial activity, especially at a reactor pH of 6 to 7. This paper focuses on the effect of high sulphide concentrations on the sulphate reduction rates. The results of three investigations operating a continuous reactor, a column reactor and batchtest reactors have sho...

The article presents the results of U-Pb isotope dating (SHRIMP-II, VSEGEI, Saint Petersburg) zircon crystals extracted from plagiorhyolites Monakh Cliff in area Cape Fiolent western part Mountainous Crimea (southern suburb Sevastopol). a concordant age estimate 168.3±1.3 Ma was obtained 20 crystals. It exactly corresponds to Bajocian/Bathonian boundary Middle Jurassic according International C...

AIM Hydrogen sulphide (H2S) intoxication in man is frequently associated with a fatal outcome. In small animal models hydrogen sulphide has demonstrated profound protection against hypoxia. No reports that focus on a potential protective effect in humans have been published. METHODS The frequency and outcome of a large cohort of hydrogen sulphide intoxications is described. RESULTS From 198...

The lead–zinc ore is a typical low-grade complex polymetallic sulphide ore. Its mineralogy characterized by high content of cryptocrystalline graphite, low lead, zinc, and copper, fine grain size. However, the aggregation size sulfide mineral aggregations coarse, symbiotic relationship relatively simple. Conventional process treatment requires grinding into monomer dissociations followed prefer...

Calyptogena elongata is a small (about 7cm maximum length) species of vesicomyid clam which lives at depths of 494–503m, near the sill depth, in the Santa Barbara Channel in mildly reducing muds at low ambient oxygen concentrations. This species has abundant autotrophic sulphur-oxidizing bacteria in bacteriocytes in its gills. The stable carbon isotope composition values of its gills and other ...

Three change-over design experiments investigated the origin of hydrogen sulphide in the rumen head-space gas of dairy cows, comparing the effects of single iso-S additions of methionine, cysteine and sodium sulphate, as well as the effects of single meals of fresh ryegrass or white clover. The concentration of hydrogen sulphide in rumen gas declined close to zero within 4 h after withdrawal of...

The oxidation of a number of thioethers, namely methyl phenyl sulphide (1), ethyl phenyl sulphide (2), isopropyl phenyl sulphide (3), n-propyl phenyl sulphide (4), p-chlorophenyl methyl sulphide (5), p-nitrophenyl methyl sulphide (6) and methyl naphthalene sulphide (7), by recombinant pea cytosolic ascorbate peroxidase (rAPX) and a site-directed variant of rAPX in which the distal tryptophan 41...

BACKGROUND Bacterial production of anionic sulphide is increased in the colon of ulcerative colitis and sulphides can cause metabolic damage to colonocytes. AIMS To assess the reversal of the damaging effect of sulphide to isolated colonocytes by methionine and methionine derivatives. METHODS AND SUBJECTS Isolated colonocytes were prepared from rat colons and 12 human colectomy specimens. I...