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Vanadium concentration ocean

Consider the atmospheric concentrations of vanadium in areas as remote as possible from man s activities. Few data of this sort exist, but they are suflBcient to suggest trends that deserve further investigation. In Table I, we summarize the available data on vanadium from remote areas of the Pacific Ocean and Canada. The small concentrations observed, down to 0.1 ngram/meter illustrate the diflSculty of the measurements noted above. By contrast, in some cities, vanadium concentrations are sometimes a few /xgrams/meter (see Table V), ten thousand times greater than in the Eastern Pacific. [Pg.32]

Emerson SR, Huested SS (1991) Ocean anoxia and the concentrations of molybdenum and vanadium in seawater. Marine Chem 34 177-196... [Pg.525]

By far the most important ores of iron come from Precambrian banded iron formations (BIF), which are essentially chemical sediments of alternating siliceous and iron-rich bands. The most notable occurrences are those at Hamersley in Australia, Lake Superior in USA and Canada, Transvaal in South Africa, and Bihar and Karnataka in India. The important manganese deposits of the world are associated with sedimentary deposits the manganese nodules on the ocean floor are also chemically precipitated from solutions. Phosphorites, the main source of phosphates, are special types of sedimentary deposits formed under marine conditions. Bedded iron sulfide deposits are formed by sulfate reducing bacteria in sedimentary environments. Similarly uranium-vanadium in sandstone-type uranium deposits and stratiform lead and zinc concentrations associated with carbonate rocks owe their origin to syngenetic chemical precipitation. [Pg.49]

High EF values were also noted for Cu (<90-400), Zn (<120-830), and Mn (1-500), with the lower ranges reported for the rural airport site. Iron showed relatively low EF values (< 1 to 30). Vanadium exhibited EF values generally from 1 to 10 with the exception of one event where the value was 68. Concentrations from chromium never exceeded 30 ppb with EF values ranging from 25 to 100. Halogen EF values, when compared to sodium concentrations in the ocean, were generally less than 10 with the exception of iodine. The iodine enrichment is believed not to be anthropogenic but to arise From preferential enrichment from the oceans (7). [Pg.217]

Phosphorus and vanadium, which are typically present in seawater as dissolved oxyanion species, have been shown to exhibit systematic plume-particle P Fe and V Fe variations which differ from one ocean basin to another (e.g., Trefry and Metz, 1989 Feely et al., 1990). This has led to the hypothesis (Feely et al., 1998) that (i) plume P Fe and V Fe ratios may be directly linked to local deep-ocean dissolved phosphate concentrations and (ii) ridge-flank metalliferous sediments, preserved under oxic diagenesis, might faithfully record temporal variations in plume-particle P Fe... [Pg.3066]

One promising method of extracting elements from sea water uses marine organisms. Many marine animals concentrate certain elements in their bodies at levels many times higher than the levels in sea water. Vanadium, for example, is taken up by the mucus of certain tunicates and can be concentrated in these animals to more than 280,000 times its concentration in sea water. Other marine organisms can concentrate copper and zinc by a factor of about 1 million. If these animals could be cultivated in large quantities without endangering the ocean ecosystem, they could become a valuable source of trace metals. [Pg.11]

Levels of vanadium measured in ambient air vary widely between rural and urban locations. Concentrations measured over the South Pole ranged from 0.001 to 0.002 nanograms (ng) of vanadium per cubic meter (m (WHO 1988) and are frequently two orders of magnitude smaller than those over the ocean at middle latitudes (WHO 1988). For example, measurements taken at nine rural sites located in the Eastern Pacific averaged 0.1 ng vanadium/m (range 0.02-0.8 ng vanadium/m ). Similar measurements taken at five different rural sites in northwestern Canada were found to average 0.72 ng vanadium/m (range 0.21-1.9 ng vanadium/m (Zoller et al. 1973). [Pg.76]

Extensive measurements on the concentration of vanadium in Boston Harbor waters have been reported20. An average value of 3.2 0.7 pg/1 has been reported for filtered sea water. The data for Massachusetts coastal water is within agreement of other coastal areas North West Pacific Ocean, 2.6—3.5 Plymouth, England, inshore, 5—7 Plymouth, England, offshore, 2.4-2.7 Wakayama Prefecture, Japan,... [Pg.7]

Since V)o is found in the media spectra obtained from cells exposed to both pH 6.5 and pH 4.0 media, after formation of the cell-associated Vio it is most likely that V,o has been extruded into the medium. After exposure to cells overnight, the pH 6.5 medium did not drop below pH 6.2, making it unlikely that the V,o formed spontaneously. Since the formation of V,o requires an acidic environment and the cytoplasmic pH values are nearly neutral, it is likely that Vio is formed in acidic vesicles prior to extrusion. There is precedence for the concentration of vanadium from the ocean by ascidians." These invertebrate animals are believed to concentrate the vanadium in vesicles that are acidic and/or contain the appropriate chelating agents." During the uptake/concentration the vanadium(V) is reduced to vanadium(IV) and/or vanadium(III) in the ascidians. It is possible that our observations in yeast may use an analogous mode of action. [Pg.189]

The concentration of vanadium in natural waters (sea and river) has been found to be very low and in the range of 0.5-2.5 j,g/liter [14], The principle dissolved species in seawater appears to be V02(0H)3 [15]. Environmental mobilization of vanadium and its compounds occurs by a number of means in the net transport of vanadium into the oceans. Some of these transport processes include terrestrial runoff, industrial emissions, atmospheric washout (vanadium in the air comes only from human activity, as there are no significant natural sources), and river transport and oil spills, resulting in a complex ecological cycle [16]. [Pg.654]

FIG. 8.4 The arrow through the ocean. Top-. The redox potential of different reduction-oxidation pairs corresponds to the order in which reduced and oxidized forms were encountered and used by life. Elements with lower redox potentials were oxidized earlier than elements with higher redox potentials. For example, ammonia/nitrogen, sulfide, and molybdenum (IV) are more easily oxidized than copper (I) and vanadium (III). Bottom Because iron (III) readily precipitates out of solution as iron oxide, over time iron concentrations decreased. Because copper (II) compounds are generally more soluble than copper (I), oxidation increased overall copper availability. This trend can be summarized by an arrow pointing away from iron and toward copper. [Pg.172]


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