公开(公告)号：US5108178A

公开(公告)日：1992-04-28

申请号：US500880

申请日：1990-03-29

申请人： Konosuke Oishi ,  Katsuhito Harada ,  Masamichi Tsukada ,  Kazuo Moriya ,  Toyoharu Okumoto

发明人： Konosuke Oishi ,  Katsuhito Harada ,  Masamichi Tsukada ,  Kazuo Moriya ,  Toyoharu Okumoto

IPC分类号： G01N21/31 ,  G01N21/74

CPC分类号： G01N21/74

摘要： An atomic absorption spectrophotometer includes a sample-atomizing portion for ashing and atomizing a sample, a power source operable to supply electric current to the sample-atomizing portion, a controller for controlling the operation of the power source, a pair of pressure regulators for setting a flow rate of an inert gas according to an ashing step and an atomization step in the sample-atomizing portion, a pair of movable valves respectively provided downstream of and connected to the pair of pressure regulators, and a filter device provided between the pair of movable valves and the sample-atomizing portion. Either of the pair of movable valves is activated into open or closed condition in synchronism with the operation of the power source so as to select the flow rate of the inert gas into the sample-atomizing portion. An electromagnetic shut-off valve for use in the atomic absorption spectrophotometer includes a valve housing having a valve chamber, and a movable valve body housed in the valve chamber. The movable valve body is movable between open and closed positions so as to open and close a gas flow line. The wall of the valve chamber is coated with a non-metallic material.