| 摘要 |
FIELD: analytical instrumentation engineering. ^ SUBSTANCE: proposed device that can be used for mass-spectrometry and analyses of molecular and isotope composition of materials ionized by electron impact method, analytical chemistry, molecular and nuclear physics, geology and geochronology, medicine, environment control, and other industries has ionizing chamber with holes for inlet and outlet of electron beam, electron-optic and ion-optic systems, and molecule sample beam shaping system incorporating sample inlet unit and two cryotraps each made in the form of two coaxial flasks of which internal one is meant for holding liquid nitrogen and space between flasks, for vacuum degassing. Mentioned cryotraps are provided with sorbent-holding baskets communicating via ducts with degassing space accommodating heat shields. Degassing space of cryotraps is separated from vacuum space of ion source by gas-tight partition; inner surfaces of degassing space of cryotraps and shields are covered with low-emissivity (high-reflectivity) coatings at temperature close to that of liquid nitrogen. Ion source incorporates provision for preventing its pollution by products being analyzed. ^ EFFECT: extended continuous running time of ion source, enhanced reliability and precision of mass-spectrometry analysis. ^ 2 cl, 2 dwg |
