现代实验室型X射线荧光元素分布成像和形态分析技术的研究进展

A Review of the Development of Modern Laboratory X-Ray Fluorescence El ement Distribution Imaging and Species Analysis Technology

近年来,随着X射线光源、单色、聚焦及探测系统的发展,在实验室可借助低功率X射线光源开展X射线荧光(XRF)和X射线吸收谱(XAS)分析。液体金属射流源等新型X射线光源系统、闭合反馈系统、电荷耦合元件和方孔微通道板等技术和计算方法的进步促进了聚焦扫描型、全场型和XRF计算机断层扫描等实验室型XRF元素空间成像技术的发展。超环面、球面和柱状弯晶等单色聚焦系统的发展推动了实验室型XAS技术的发展。探索新型的实验室X射线光源系统,开发更高效的单色聚焦系统,推动X射线动态电影拍摄技术等将是未来研究的重要发展方向。

In recent years,with the development of X-ray source,X-ray monochromatic-focusing and detector technology and calculation methods,X-ray fluorescence(XRF)and X-ray Absorption Spectroscopy(XAS)is used to obtain better two-dimensional/three-dimensional element spatial distribution characteristics and element morphology and coordination information in the lab and widely applied in geology,environment,biology,materials,medicine,art,cultural heritage and industry.However,more requirements are put forward to analyze spatial element distribution and species characteristics in the lab,such as analyzing unigue samples with complex matrices,obtaining better detection limits and shorter detection time,and higher spatial resolution,etc.Laboratory-type XRF element spatial distribution and imaging technology are divided into focus scanning type 2D/3D XRF element spatial distribution imaging technology(focus scanning 2D/3D XRF),full field-micro X-ray fluorescence(FF-MXRF)and XRF computer Tomography(XRF-CT).The advancement of 2D/3D XRF hardware technology includes:liquid metal jet source and pyroelectric X-ray generator and other new laboratory X-ray source have improved the excitation efficiency closed-loop feedback systems overcome problemes caused by rough sample surfaces.X-ray monochromatic and vacuum systems play an important role in reducing background and light elements interferences.Pn-charge coupled device and micro pore optic have promoted the progress of FF-MXRF;The development of monochromatic focusing systems such as toroidal curved crystal,spherical curved crystal and columnar curved crystal have enabled laboratory XAS technology development.The continuous improvement of calculation methods has greatly promoted laboratory XRF element spatial distribution imaging technology and laboratory XAS technology,especially the development of 2D/3D XRF and XRF-CT.Exploring laboratory X-ray source systems,efficient monochromatic and focusing optical systems,and promoting dynamic X-ray film shooting technology are essential in the future.