| 摘要 |
<p>A standardized collector surface (3), with appropriate selective absorption, is contacted in well-determined conditions with the gas, the liquid or the solid in order to sample, concentrate and optionally effect a well-determined chemical reaction of the trace element to be measured. The collector surface is then taken to a contact membrane (1) heated and swept by a carrier gas (2) from the receiver head of an analysis apparatus in order to obtain the analysis of the absorbed gas and/or of the reaction product thereof. The trace elements quantatively thermally desorbed by the collector surface (3) are put in a solution, are subjected to a diffusion and an evaporation by traversing the contact membrane (1) and are carried away by the carrier gas (2) through a sampling conduit or a fractionating column by gas-chromatography towards a gas analyser, for example a mass spectrometer (MS). The sampling method for analyzing qualitative and quantitative traces by means of gas-chromatography (GC) and the combination of MS/GC, is simple, very fast and universal. This method is appropriately used for routine work in analyzing the environement, residues, food materials, quality controls, medical and chemical analysis, toxicology, microbiology, research on guinea pigs, pharmacology, doping control, criminalistics, and forensic medicin.</p> |
