Marine systems

Observations of the ratio of oxidized plutonium to reduced plutonium may provide some insight to the observations of erratic formation and lack of equilibration in laboratory solutions at ORNL versus fairly consistent and predictable behavior in oligo-trophic lakes and marine systems. In coastal water and the relatively shallow Lake Michigan, Pu(V) is about 90 percent of the soluble plutonium, but in the upper waters of the open ocean, where it does not interact with the seafloor due to the depths,... [Pg.303]

Of the possible substituting ions, COi ion is by far the most important followed by Na, S04 and Mg. The most common form of natural apatite in sedimentary rocks is francolite, a substituted form of carbonate fluorapatite deposited in marine systems. The substitution of col ior>s into the mineral lattice has a substantial effect on apatite solubility (Jahnke, 1984). More studies are required, however, before the effects of all substituting ions are imderstood and an accurate assessment of the solubility of complex, natural apatites can be made. [Pg.362]

Fig. 17-3 (a) A simplified picture of the coupling of biogeochemistry and global radiative balance in marine systems. SST = Sea surface temperature. [Pg.443]

Fisher NS, Reinfelder JR (1995) The trophic transfer of metals in marine systems. In Tessier A, Turner DR (eds) Metal speciation and bioavailability in aquatic systems. Wiley, Chichester, p 363... [Pg.53]

Natural pigment production for food coloration includes the entire spectrum of biotechnologies. For example, biological production of carotenoid pigments has medical implications because carotenoids are nutritive (pro-vitamin A), antioxidant, and photoprotective. Carotenoids are produced alternately in agricultural systems (plants), industrial bioreactors (bacterial and fungi), and marine systems (cyanobacteria and algae). [Pg.350]

Analysis of total zinc by anodic stripping voltammetry is problematic because of interference by the hydrogen wave in acidified samples, and due to the inability to detect organically complexed zinc at natural pH values near 8 [ 185]. An improved understanding of zinc in marine systems now requires rapid, sensitive analytical methods that are less prone to contamination, and that can be performed at sea [624],... [Pg.235]

Many volatile organic compounds (hydrocarbons, alcohols, aldehydes, acids, esters, ketones, amines, etc.) have been identified in marine systems [ 156,157]. These volatile materials may have an important role in the cycling of organic... [Pg.503]

Sanders, J.G. and G.R. Abbe. 1989. Silver transport and impact in estuarine and marine systems. Pages 5-18 in G.W. Suter II and M.A. Lewis (eds.). Aquatic Toxicology and Environmental Fate eleventh volume. Amer. Soc. Testing Mater., Spec. Tech. Publ. 1007, Philadelphia, PA 19103. [Pg.580]

Sanders, J.G. 1980. Arsenic cycling in marine systems. Mar. Environ. Res. 3 257-266. [Pg.1540]

KEYWORDS metals, marine systems, transformation/dissolution protocol... [Pg.99]

This is an on-going project aimed at examining the T/D characteristics of metals and alloys in a marine medium in seven- and twenty eight-day tests. The data obtained to date on seven-day tests of cuprous oxide (Cu20) and nickel metal powder (Ni) provides useful comparisons with those reported earlier for the freshwater OECD 203-based media at pH 6 and 8 (Skeaff Hardy 2005) and insight into the behaviour of metal-bearing substances used in commerce under marine conditions of the T/DP. The data supports an approach directed to the eventual adaptation, validation and application of the OECD T/DP to marine systems for the purposes of marine hazard classification of metals, metal compounds and alloys. [Pg.100]

American Society of Testing Materials (ASTM), F 1166. Standard Practice for Human Engineering Design for Marine Systems. Equipment and Facilities. ASTM, Philadelphia, PA, 1988. [Pg.201]

Fisher, N. S. and Reinfelder, J. R. (1995). The trophic transfer of metals in marine systems, In Metal Speciation and Bioavailability in Aquatic Systems, eds. Tessier, A. and Turner, D. R., Vol. 3, IUPAC Series on Analytical and Physical Chemistry of Environmental Systems. Series eds. Buffle, J. and van Leeuwen, H. P., John Wiley Sons, Ltd, Chichester, pp. 363 -06. [Pg.398]

Among the trace metals, Hudson and Morel [7] postulated that Fe and Zn were closest to a diffusion-limited situation based upon measured cellular metal quotas and concentrations in marine systems (e.g. Zn would be diffusion limited for cells > 20 pm). Similarly, Hassler and Wilkinson [90] showed that for cells grown under conditions of Zn starvation, transport was diffusion limited for [Zn2+] < 10 12 mol dm. Fortin and Campbell [91] showed that, in the presence of chloride, the Ag transport flux to Chlamydomonas reinhardtii was close to a diffusion limitation at the lower Ag concentrations that were examined. Diffusion limitation of trace metals is most likely in systems where the concentrations are low and concentrations of competing metals are high, especially for essential metals that are taken up by passive diffusion across the membrane [8], The final point of essentiality could be especially important when transport systems are upregulated in response to lowmetal concentrations (see also Section 2.2 [90,92]). [Pg.462]

Logan, B. E. and Hunt, J. R. (1987). Advantages to microbes of growth in permeable aggregates in marine systems, Limnol. Oceanogr., 32, 1034—1048. [Pg.520]

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