Polychlorinated biphenyls 866 INDEX

The second structural property described by the 4ypc index is the substitution pattern on the benzene ring. The value of the 4ypc index increases sharply with the degree of substitution, while in the isomeric classes of substituted benzenes it increases with the proximity of substituents. Thus, this structural parameter has also been found to be very useful in describing activities and properties of polysubstituted benzenes [103], chlorinated benzenes [279], and polychlorinated biphenyls [286]. 

Sasan, M. T., and Y. Inel, Application of the Characteristic Root Index Model to the Estimation of /V-Octanol / Water Partition Coefficients Polychlorinated Biphenyls. Chemosphere, 1995 30, 39-50. 

Klappa, S.A. and Long, G.R. (1992). Computer Assisted Determination of the Biological Activity of Polychlorinated Biphenyls Using Gas Chromatographic Retention Indexes as Molecular Descriptors. Anal.Chim.Acta, 259,89-93. 

The concerns aroused by methylmercury in fish, arising from the susceptibility of the developing brain to this neurotoxicant, led to the design and execution of two large prospective studies. One was located in the Seychelle islands, which lie in the Indian Ocean. The other was located in the Faroe Islands, which lie in the North Sea. Both communities consume large quantities of seafood. In the Seychelles, it is almost exclusively in the form of fish. In the Faroes, virtually all the methylmercury comes from the consumption of pilot whales, which are also contaminated with polychlorinated biphenyls (PCBs). Both studies assayed maternal exposures to methylmercury. In the Seychelles, maternal hair was used as the index it reflects the history of blood levels. The Faroes study relied primarily on cord blood. 

Saqan, M.T. and Inel, Y. (1995) Application of the characteristic root index model to the estimation of n-octanol-water partition coefficients. Polychlorinated biphenyls. Chemosphere, 30, 39-50. 

Non-Metallic Impurities Viscosity index (VI) improvers or polychlorinated biphenyls, PCBs, can be determined by dialysis or chlorine analysis, respectively. Indication of the presence of VI improver is given by unusually high viscosity indices. Solvent extraction can remove VI improvers or their fragments. 

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