Monochromatic Excitation X-ray Fluorescence Spectrometer

Abstract

The invention discloses a monochromatic excitation X-ray fluorescence spectrometer, comprising: (1) an x-ray source selected to generate an x-ray beam, (2) an optical device for focusing the x-ray beam generated by the x-ray source onto a sample device, and select the desired energy of x-rays, (3) energy-resolving x-ray detectors. The configuration of the monochromatic excitation X-ray fluorescence spectrometer is as follows: (i) The X-ray source adopts a low-power X-ray tube not greater than 50W, and the X-rays emitted by it are divergent and have a definite spot size, (ii) Optical components Using a logarithmic spiral to rotate the hyperboloid artificial lens, so as to completely and only focus the X-rays of the desired energy emitted by the X-ray source, and have extremely high diffraction efficiency, (iii) The energy-resolving X-ray detector preferably adopts silicon drift Semiconductor detectors. The spectrometer adopting the above configuration is a small, simple, low-cost monochromatic excitation X-ray fluorescence spectrometer with extremely low detection limit.

Description

technical field [0001] The invention relates to a spectrometer, in particular to a monochromatic excitation X-ray fluorescence spectrometer comprising a logarithmic spiral rotating hyperboloid artificial crystal. The extremely low detection limit achieved by the spectrometer is especially suitable for the detection of trace elements in materials, such as silicon, sulfur, chlorine, etc. in low concentrations in fuels, oils and additives. Background technique [0002] In recent years, with the basic achievement of the goal of a well-off society, my country is making great strides towards developing countries, and ordinary people's awareness of environmental protection is increasing. In order to reduce the emission of harmful pollutants to the environment, the country has improved the quality standard of vehicle fuel, and the limit requirement for sulfur concentration has been reduced from 50ppm (vehicle gasoline, diesel national IV) to 10ppm (vehicle gasoline, diesel national ...

AI Technical Summary

Problems solved by technology

Although these two types of methods have extremely low detection limits, which are far below the above-mentioned requirements for detection limits, they all have obvious disadvantages: such as high power (~6kw), high vacuum or inert ambient gas, complicated sample preparation and processing requirements, etc., and is expensive

[0006] This existing doubly curved crystal is based on John geometry, one limitation is the low radiation collection angle, methods to overcome this limitation have been disclosed in U.S. Patent No. 5,127,028 and U.S. Patent No. 7,035,374, but still have limitations

Both of these two patents use the method of splicing multiple diffractive crystals, so it is difficult to manufacture; although these two patents overcome this limitation, due to the characteristics of John's geometry itself, it is not fully focused geometrically

This existing doubly curved crystal also uses natural crystals (for example, germanium (Ge) or silicon (Si) crystals), and the integral diffraction efficiency of natural crystals is not high

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