Study on X-Ray Spectroscopic Analysis by the Use of Nuclear Radiations from Radioisotopes

摘要

The basis and practice of analytical application of the characteristic X rays of low atomic number elements excited by mainly alpha rays from radioisotopes were studied. Some alpha emitters were proved to be advantageously usable to those elements, in particular, very low atomic number elements, despite their accompanying radiations. Operating characteristics of gas flow proportional counters were fully investigated, and besides, the characteristics of pulse-height distribution continuum in those counters and semiconductor detectors were comparatively studied as the detector for the low energy X rays. For calibration in quantitative analysis by the X-ray spectroscopy, a new simple semitheoretical method for thin specimens is proposed and on the other hand general formulae for matrix correction in thick specimens was derived. An industrial X-ray analyzer to simultaneously analyze four main elements of cement raw material mixtures was constructed with the use of a exp 210 Po alpha-ray source and gain-controlled proportional counters. Problems in practical analysis for the process control were solved and the analyzer has been used routinely in the process for more than ten years. Another analytical application to airborne dust is described as a typical example of application of the proposed calibration method for thin specimens. (Atomindex citation 08:343585)