摘要 |
1,109,160. Gas analysis. VARIAN ASSOCIATES. Nov.29, 1966 [Dec. 6, 1965(2); June 6, 1966; July 6, 1966], No.53450/66. Heading G1B. A sampling arrangement for introducing gaseous materials from a source e. g. a gas chromatograph, into an analyzer, e. g. a mass spectrometer comprises a membrane 13, free of holes, and in which the permeability of permanent gases such as are used as the carrier in a gas chromatograph is substantially less than that of the gases which are to be detected, a vacuum pump being connected so as to establish a pressure differential across the membrane such that the lower pressure region is connected to the analyzer. The membrane 13 may be formed either from a polymer, e. g. a polysiloxane, which may have a liquid phase coating 24, or from a stationary liquid phase confined within a thin-wall vessel constructed of gas-permeable material. In use the gases to be detected are arranged to be soluble in the membrane and in this way are separated from the carrier gas and permeate the membrane. The membrane 13 may be supported by a perforated support 23 and is hermetically sealed in a member 11 for connection between the gas source on one side, and the vacuum pump and analyzer on the other. If desired two similar membranes may be used in series in the gas line to the analyzer. |