Master Analytical Scheme

On-going studies to improve analytical methods for hexachloroethane and related compounds include the EPA "Master Analytical Scheme" being developed for organic compounds in water (Michael et al. 1988) and the research in supercritical fluid extraction (Lopez-Avila et al. 1991 Wieboldt et al. 1988). Research continues on improving extraction, concentration, and elution techniques, and detection devices (Eichelberger et al. 

Pellizzari, E. D. et al. Master Analytical Scheme for Organic Compounds in Water U.S. Environmental Protection Agency. U.S. Government Printing Office Washington, DC, 1985 EPA/600/54-85. 

Application of the Master Analytical Scheme to Polar Organic Compounds in Drinking Water... 

The U.S. Environmental Protection Agency Master Analytical Scheme (MAS) for Organic Compounds in Water provides for comprehensive qualitative-quantitative analysis of gas chromatographable organic compounds in many types of water. 

Figure 1. Master analytical scheme flow diagram.

Research is ongoing to develop a "Master Analytical Scheme" for organic compounds in water (Michael et al. 1988), which includes chlorobenzene as an analyte. The overall goal is to detect and. quantitatively measure organic compounds at 0.1 pg/L in drinking water, 1 pg/L in surface waters, and 10 pig/L in effluent waters. Analytes are to include numerous semivolatile compounds and some compounds that are only "semi-soluble" in water, as well as volatile compounds (bp < 150°C). 

Norwood DL, Michael LC, Cooper SD, et al. 1986. An application ofthe "Master Analytical Scheme" to influent and effluent wastewaters. In Advances in water analysis and treatment. Proceedings of Water Quality Technology Conference, Portland, OR, November, 365-386. 

Michael EC, Pelizzari ED, Norwood DE. 1991. Application of the master analytical scheme to the detennination of volatile organics in wastewater influents and effluents. Environ Sci Technol 25(l) 150-155. 

Pellizzari ED, Sheldon LS, Bursey JT, et al. 1985a. Master scheme for the analysis of organic compounds in water, state-of-the-art review of analytical operations. Washington, DC U.S. Environmental Protection Agency. 

No other analytic solution to the master equation for a weak collision system over the whole range of pressures has yet been found. A solution is known, at the low pressure limit only for a rather limited exponential probability model of a unimolecular reaction [77.T2 80.F1], and Troe has developed empirical schemes for determining the pressure range over which the fall-off exhibits curvature and for joining smoothly the high and low pressure limiting solutions [77.Q 79.T2]. 

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