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Conductive polymers were obtained with a new polymerization method in which UV light was used as a photochemical initiator. In a previous work, optimum irradiation times were determined to obtain high conversion percentages. The effect of dopants on the conductivity of the polymer poly(ethylene glycol dimethacrylate) (PEGDM) was studied with LiClO 4 and I 2 as a dopant. The most effective dopant concentration was determined by the measurement of conductivities. Through the tracing of the conductivity change at various temperatures during the reaction of PEGDM with the dopant, the activation energies of the interactions were calculated, and a method was developed to follow the kinetics of the polymerization reaction with a conductometric technique. This work presents a nuclear magnetic resonance (NMR) study of the same polymer prepared under the optimum conditions with the results obtained in a previous study. NMR spectroscopy was used to determine the relaxation time, rate constants, and activation energy of the polymer-dopant interactions. As a preliminary study, pyruvic acid was used, and for acid-catalyzed pyruvic acid/water reactions, the relaxation time, activation energy, and enthalpy change values (⌬H) were determined. With the same NMR technique, the reaction mechanisms of the polymerization, relaxation times, and rate constants of the polymer-dopant interactions were determined. The polymerization pathway was determined with NMR spectra; the results were confirmed by the calculation of the activation energies and bond-breaking energies.

The edible parts of several species of fish and other marine organisms inhabiting the Calcasieu River/Lake, Louisiana were analyzed for Cd, Cr, Cu, Pb, Hg, Ag, Zn and As. Concentrations of all metals measured in both intra and interspecies showed no significant variation with sample location. Differences in elemental concentrations were related to organism mobility and not to site-specific variations in metal loadings. Different species of finfish contained only trace amounts of Cd (0.02-0.08), Ag (less than 0.01-0.3), Pb (less than 0.2-0.5), and As (less than 0.1-0.3) mg kg(-1). Concentrations of Cu and Cr were highly variable, in contrast to Zn, which was present in relatively constant amounts across all species (28 +/- mg kg(-1). Sessile organisms such as oysters had the highest concentrations of heavy metals, including Cd. Periphyton and zooplankton were the only groups that showed differences in metal concentrations with sampling location.

Two species of lichen native to southwest Lousiana, Parmotrema praesorediosum (Nyl.) Hale and Ramalina stenospora, Mull. Arg. have been investigated as air pollution monitors. Over the period 1983-88 samples were collected at 18 stations in the Lake Charles/Westlake/Sulphur area. The samples were analyzed for A1, Fe, Cu, Pb, Cd, Hg, Cr, and Zn. When metal concentrations in lichens were plotted vs year for certain representative stations, a dramatic reduction in the concentrations of certain metals was seen after 1983. When the most recent data are compared with those previously obtained, the effects of the industrial zone, which was previously demonstrated, have now all but disappeared.