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Sulphate marine

Methanogenesis important process in freshwater wetlands, waterlogged soils and in deeply buried low-sulphate marine sediments 2CH20 - CH4 + C02 -58... [Pg.103]

De Riccardis, F., Minale, L., Ricdo, R., Giovannitti, B., lorizzi, M., and Debitus, C. (1993a) Phosphated and sulphated marine polyhydroxylated steroids from the starfish Tremaster novaecaledoniae. Gazz. Chim. Ital., 123, 79-85. [Pg.1109]

An important indusuial interest is in the conosion of metals and ceramics by molten sodium sulphate/vanadate solutions. This is because turbines, which are usually nickel-based alloys, operating in a marine anuosphere, containing... [Pg.319]

Aggressive environments include marine conditions and particularly industrial atmospheres containing high concentrations of acid gases such as sulphur dioxide rain washing is benehcial in both environments, while dampness and condensation alone can accentuate the rate of attack in the presence of chlorides and acidic sulphates. [Pg.664]

Sulphur attack on nickel-chromium alloys and nickel-chromium-iron alloys can arise from contamination by deposits resulting from the combustion of solid fuels, notably high-sulphur coals and peat. This type of corrosion, which has been observed on components of aircraft, marine and industrial gas turbines and air heaters, has been associated with the presence of metal-sulphate and particularly sodium sulphate arising directly from the fuel or perhaps by reaction between sodium chloride from the environment with sulphur in the fuel. Since such fuels are burned with an excess of air, corrosion occurs under conditions that are nominally oxidising although the deposits themselves may produce locally reducing conditions. [Pg.1064]

Low-carbon and chromium-nickel steels, certain copper, nickel and aluminium alloys (which are all widely used in marine and offshore engineering) are liable to exhibit stress-corrosion cracking whilst in service in specific environments, where combinations of perhaps relatively modest stress levels in material exposed to environments which are wet, damp or humid, and in the presence of certain gases or ions such as oxygen, chlorides, nitrates, hydroxides, chromates, nitrates, sulphides, sulphates, etc. [Pg.79]

Sulphates and chlorides are present in industrial and marine atmospheres. In water they accelerate the corrosion of steel. Avoiding lodgement areas for water and dirt reduces the risk of the latter acting as a poultice in which the corrosive salts can build up. [Pg.326]

Parkes RJ, GR Gibson, I Mueller-Harvey, WJ Buckingham, RA Herbert (1989) Determination of the substrates for sulphate-reducing bacteria within marine and estuarine sediments with different rates of sulphate reduction. J Gen Microbiol 135 175-187. [Pg.274]

Galushko A, D Minz, B Schink, F Widdel (1999) Anaerobic degradation of naphthalene by a pure culture of a novel type of marine sulphate-reducing bacterium. Environ Microbiol 1 415-420. [Pg.419]

Latham AG, Schwarz HP (1992) Carbonate and sulphate precipitates. In Urarrium-series disequilibrium Applications to Earth, Marine and Environmental Sciences, Ivanovich M, Harmon RS (eds) Oxford University Press, Oxford, p 423-459... [Pg.456]

Strontium sulphate (celestite) Exoskeletons of a few marine organisms... [Pg.254]

Yuan, M., A.C. Todd and K. S. Sorbie, 1994, Sulphate scale precipitation arising from seawater injection, a prediction study. Marine and Petroleum Geology 11, 24-30. [Pg.535]

Kido et al. [6] determined basic organic compounds such as quinoline, acridine, aza-fluorene, and their N-oxides in marine sediments found in an industrial area. The sediments were extracted with benzene by using a continuous extractor for 12h. Hydrochloric acid solution (IN) was added to the benzene extracts, and the mixture was shaken for 5min the acid layer separated from the benzene layer was made alkaline by the addition of sodium hydroxide, and the alkaline aqueous solution was extracted with diethyl ether the ether extracts were then dehydrated with anhydrous sodium sulphate and concentrated with a Kuderna-Danish evaporator. The concentrations were separated and analysed by gas chromatography-mass spectrometry and gas chromatography high-resolution mass spectrometry. [Pg.191]

Collier et al. (10) demonstrated that HPLC was an effective technique for the separation of aromatic hydrocarbon metabolites in exposed marine organisms. Radioactive bioconversion products were studied in liver and gall bladder of coho salmon dosed with H-naphthalene. Quantitative identifications of glucuronide, sulphate, dihydrodiol, glycoside, and 1-naphthol derivatives were obtained. Three additional polar compounds of unknown structure were found. A typical HPLC profile is shown in Figure 2. [Pg.66]

Shen Y, Knoll AH, Walter MR (2003) Evidence for low sulphate and anoxia in a mid-Proterozoic marine basin. Nature 423 632-635... [Pg.453]

The reason why SIA is higher in urban areas is less obvious as these are secondary aerosols. The observed increment is predominantly caused by more nitrate and sulphate. The reaction of nitric acid and sulphuric acid with the sea-salt aerosol in a marine urbanised environment follows an irreversible reaction scheme. In essence, the chloride depletion stabilises part of the nitrate and sulphate in the coarse mode and may partly explain part of the observed increment. However, it also raises the question how to assign the coarse mode nitrate in the mass closure. The sea salt and nitrate contributions cannot simply be added any more as nitrate replaces chloride. Reduction of NOx emissions may cause a reduction of coarse mode nitrate, which is partly compensated by the fact that chloride is not lost anymore. A reduction would yield a net result of ((N03-C1)/N03 = (62-35)/62=) 27/62 times the nitrate reduction (where the numbers are molar weights of the respective components), and this factor could be used to scale back the coarse nitrate fraction in the chemical mass balance. A similar reasoning may be valid for the anthropogenic sulphate in the coarse fraction. Corrections like these are uncommon in current mass closure studies, and consequences will have to be explored in more detail. [Pg.255]

Thode-Andersen, S. and Jprgensen, B.B. (1989) Sulphate reduction and the formation of 35S-labeled FeS, FeS2, and S° in coastal marine sediments. Limnol. Oceanogr. 34, 793-806. [Pg.671]

Lein AYu, Ivanov MV (1983) Reduced sulphur accumulation in sediments of marine basins with high rates of sulphate reduction. In The global biogeochemical sulphur cycle, SCOPE 19. Wiley, Chichester, UK, p 413... [Pg.330]

Changes in the isotope composition of marine sulphates during geological time is another exiting topic of S isotope geochemistry (Holser and Kaplan,... [Pg.165]

T. A. Fenoradosoa, C. Delattre, C. Laroche, A. Wadouachi, V. Dulong, L. Picton, P. Andriamadio, and P. Michaud, Highly sulphated galactan from Haiymenia durvillei (Halymeniales, Rhodophyta), a red seaweed of Madagascar marine coast, Int. J. Biol. Macromol., 45 (2009) 140-145. [Pg.211]

Methane Methane is readily degraded aerobically by methanotrophs, which are members of the domain Bacteria that form CO2 and H2O from the methane, using it as a source of energy and carbon. Methane may also be anaerobically degraded in some marine environments by a microbial consortium consisting of an archaeon (e.g. a member of the Methanosarcinales) and a eubacterium (e.g. a member of the Desulfosarcinales) (e.g. Orphan et al., 2001). The archaeon forms H2 and CO2 from the methane, and the eubacterium uses the H2 to reduce seawater sulphate to H2S. The overall reaction brought about by this consortium is ... [Pg.20]


See other pages where Sulphate marine is mentioned: [Pg.503]    [Pg.503]    [Pg.424]    [Pg.339]    [Pg.728]    [Pg.961]    [Pg.1035]    [Pg.1071]    [Pg.450]    [Pg.478]    [Pg.48]    [Pg.845]    [Pg.901]    [Pg.315]    [Pg.19]    [Pg.724]    [Pg.918]    [Pg.10]    [Pg.246]    [Pg.247]    [Pg.114]    [Pg.183]    [Pg.297]    [Pg.392]    [Pg.274]    [Pg.244]    [Pg.8]    [Pg.450]   
See also in sourсe #XX -- [ Pg.21 , Pg.22 , Pg.72 , Pg.97 ]




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