ISOTOPE RATIO PLASMA MASS ANALYSER AND METHOD

摘要

PROBLEM TO BE SOLVED: To accurately analyze an isotope ratio by holding the increase coefficient showing the relation between the diameter of the opening part of an epithelium scoop-up member, the distance between the outlet side of the opening part of a sample extraction member and the inlet side of the opening part of the epithelium scoop-up member and the operation pressure of an expanding region to a specific numerical value or more. ;SOLUTION: When an increase coefficient F represented by formula F=ds/ s×(p1)1/2 [wherein ds is the diameter (mm) of the opening part 29 of an epithelium scoop-up member 19, s is the distance (mm) between the opening part 16 of a sample extraction member 15 and the inlet side of the opening part 29 and PI is the operation pressure (mB) of an expanding region] is held to a value of 0.8B1/2 or more, the measuring accuracy of an isotope ratio becomes high generally. For example, when the diameter 34 of a barrel shock 31 is reduced and the inlet side of the opening part 29 (the position 33 of a Mach disk when there is no member 19) is allowed to approach the opening part 16 of the member 15, both members 15, 19 approach and the distance (s) becomes 2-3mm usually and the coefficient F can be set to about 1.5mB.;COPYRIGHT: (C)1996,JPO