静作動質量分析計
1959 年 28 巻 10 号 p. 584-593
詳細
1959 年 28 巻 10 号 p. 584-593
A mass spectrometer has been designed for the use of analysing very small amount of gas samples and for the study of adsorption in ultra high vacuum.
The spectrometer is of 60° type and made of all glass. The radius of ion orbit is 11cm and the resolving power is 60. All-glass greaseless valves are used for the spectrometer to be operated statically.
The operating pressure is 1.1s×10-9mmHg which can be maintained over two hours. As the operation is static, the sensitivity (the amount of sample required to obtain signal of the same order as noise) is reduced to 1.3×10-9cc N. T. P. for argon, which is 1/15, 000 of the amount needed by the usual flow method.
The tests of analysis are made with rare gases, nitrogen, carbon-monoxide, methane, n-butane, hydrogen, oxygen and carbon-dioxide.
The gases so far found analysable by static method are rare gases, nitrogen, carbon-monoxide and methane, but because of the rapid decrease of enclosed samples, other gases can not be analyzed: carbon-dioxide and oxygen due to adsorption in the analyzer tube, and n-butane due to thermal decomposition by filament.
The spectrometer is also used for analysing radiogenic argon in minerals and residual gases in a magnetron and for studying adsorption of various gases by Bayard-Alpert gage in ultra-high vacuum.
