Study on the Trends of Atmospheric CFCs
大气中氯氟烃类物质浓度变化的研究

The method of detecting atmospheric CFCs using gas chromatograph(ECD detector) was established.Through the procedure,the method of cryogenic dehydration and concentrating was introduced.The CFCs concentration of Shanghai clean air was detected and was compared with that of The University of Tokyo,Japan.The result shows that,since 1997,the atmospheric concentrations of CFC-11 and CFC-12 have decreased.Shanghai's emission of CFCs is in a low level compared with the developed countries.