Trace metals interactions

Sunda, W. G. (1988/89). Trace metal interactions with marine phytoplankton, Biol. Oceanogr., 6, 411-442. 

Sunda, W.G. (1991), "Trace Metal Interactions with Marine Phytoplankton". Biol. Oceanography 6, 411-442. 

Figure 8.12 Schematic representation of trace metal interactions in a system containing an inorganic surface, micro-organisms and micro-organism exopolymers (adapted from Lion eta/., 1988). In a natural aquatic system other complexing substances will be present, namely fulvic-type compounds, which will interact with the metals, the solid surface and the biopolymers (Buffi eetal., 1998).

Lion, L.W., Shuler, M.L., Hsieh, K.M. and Ghiorse, W.C. (1988) Trace metal interactions with microbial biofilms in natural and engineered systems. CRC Crit. Rev. Environ. 

Nature of Trace Metal Interactions with Humic Substances... 

Webster, J. G., Fyfe, W. S., Webster, K. S., and Hawes, I. (1996). Trace Metal Interaction with Antarctic Microbial Communities. 4th Int. Symp. Geochem. Earth s Surf., 494-498. 

Many applications of novolacs are found in the electronics industry. Examples include microchip module packaging, circuit board adhesives, and photoresists for microchip etching. These applications are very sensitive to trace metal contamination. Therefore the applicable novolacs have stringent metal-content specifications, often in the low ppb range. Low level restrictions may also be applied to free phenol, acid, moisture, and other monomers. There is often a strong interaction between the monomers and catalysts chosen and attainment of low metals levels. These requirements, in combination with the high temperature requirements mentioned above, often dictate special materials be used for reactor vessel construction. Whereas many resoles can be processed in mild steel reactors, novolacs require special alloys (e.g. Inconel ), titanium, or glass for contact surfaces. These materials are very expensive and most have associated maintenance problems as well. 

An evaluation of the fate of trace metals in surface and sub-surface waters requires more detailed consideration of complexation, adsorption, coagulation, oxidation-reduction, and biological interactions. These processes can affect metals, solubility, toxicity, availability, physical transport, and corrosion potential. As a result of a need to describe the complex interactions involved in these situations, various models have been developed to address a number of specific situations. These are called equilibrium or speciation models because the user is provided (model output) with the distribution of various species. 

Luoma, S.N. and G.W. Bryan. 1979. Trace metal bioavailability modehng chemical and biological interactions of sediment-bound zinc. Pages 577-609 in E.A. Jenne (ed.). Chemical Modeling in Aqueous Systems. Amer. Chem. Soc., Sympos. Ser. 93, Washington, D.C. 

Campbell, P. G. C. (1995). Interactions between trace metal and aquatic organisms a critique of the free-ion activity model. 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. 45-102. 

Jackson, G. A. and Morgan, J. J. (1978). Trace metal-chelator interactions and phytoplankton growth in seawater media theoretical analysis and comparison with reported observations, Limnol. Oceanogr., 23, 268-282. 

Parent, L., Twiss, M. R. and Campbell, P. G. C. (1996). Influences of natural dissolved organic matter on the interaction of aluminum with the microalga Chlorella a test of the free-ion model of trace metal toxicity, Environ. Sci. Technol., 30, 1713-1720. 

Pagenkopf, G. K. (1983). Gill surface interaction model for trace-metal toxicity to fishes role of complexation, pH, and water hardness, Environ. Sci. Technol., 17, 342-347. 

Bruland, K. W., Donat, J. R. and Hutchins, D. A. (1991). Interactive influence of bioactive trace metals on biological production in oceanic waters, Limnol. Oceanogr., 36, 1555-1577. 

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