| 摘要 |
PURPOSE:To prevent trouble caused by flow of a fine dust during the replacement of a column free from diffusive infiltration of sample material from the column and leaving any sample material by connecting pipelines of two kinds of resistances, high and low, to a branch pipeline to run a small amount of a carrier gas ceaselessly through a high resistance pipeline. CONSTITUTION:While opening/closing valve Vl and a membrane valve Vm are left closed, a fine flow rate of a carrier gas flows to a branch path T through a high resistance passage Rh and then, to a molecule separator S. When a sample is introduced, with the opening/closing valve Vl and the membrane valve Vm left closed, a liquid sample is injected into a sample introduction section G with a injector needle through a septum (p). As the sample introduction section G is in a heating tank, the sample injected is vaporized to raise the pressure. When the membrane valve Vm is opened, the sample flows out into a pipeline T under own pressure and introduced into a mass spectrometer M. After the valve Vm is closed, the carrier continues to flow into the pipeline T to wash the sample completely. When replacing the column C, a closure plate is inserted into the molecule separator to shut off the gas flow through the mass spectrometer from the column C and then, after the opening/closing Vl is opened, the column C is removed. |
