Measurement of femtogram quantities of trace elements using an X-ray microprobe.
Measurement of femtogram quantities of trace elements using an X-ray microprobe.
复制标题
使用 X 射线微探针测量飞克级微量元素。
DOI：
10.1021/ac00160a007
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发表时间：
1988
影响因子：
7.4
通讯作者：
Rivers,ML
中科院分区：
文献类型：
--
作者：
Giauque,RD;Thompson,AC;Underwood,JH;Wu,Y;Jones,KW;Rivers,ML
用x射线微探针测量了生物材料中微量元素的飞图量。微探针采用一对凹面球镜，表面涂有钨碳多层膜。这些反射镜按照klrkpatrick - baez几何形状排列，从同步加速器白色辐射光束中产生聚焦的准单色光束。光束光斑尺寸小于10 × 10 pm，单色化光束在10 keV时具有1 keV的带通。元素Zn （Z=30）和toK （Z= 19）的最低检测限从3到70 fg不等。强同步辐射光束的发展引起了人们对用x射线荧光法测量极小样品中微量元素浓度的极大兴趣。Sparks(1)报道了使用同步辐射的x射线荧光微探针来分析黑云母中的独居石巨晕包裹体，以寻找超重原始元素。采用弯曲的镶嵌石墨晶体对同步辐射光束进行聚焦和单色化。使用能量为37kev的光子，全宽半宽（fwhm）为0.4 keV。实现了15 X 1010光子/(s mm2)的通量。实际光斑尺寸为0.64 mm2。自1981年以来，发表了许多关于x射线微探针使用的论文（2-5）。在大多数情况下，同步子白光光束都采用垂直和水平狭缝准直，或者采用双弯曲晶体聚焦辐射。获得的典型可用光束光斑尺寸约为700- 2500pm2。最近，Iida和Gohshi(6)展示了使用反射/透射镜组合来聚焦和聚焦
Femtogram quantities of trace elements In biological materials have been measured with an X-ray microprobe. The microprobe uses a pair of concave spherical mirrors which were coated with tungsten-carbon multilayers. Arranged in the Klrkpatrlck-Baez geometry, the mirrors produce a focused and quasi-monochromated beam from the synchrotron white radiation beam. The beam spot size Is lessthan 10 X 10 pm and the monochromated beam has a band-pass of 1 keV at 10 keV. Minimum detectable limits achieved varied from 3 to 70 fg for the elements Zn (Z=30) toK (Z= 19).The development of intense synchrotron radiation beams has ledto significant interest intheir application for the measurement of trace element concentrations of very small specimens by X-ray fluorescence. Sparks (1) reported the use of an X-ray fluorescence microprobe using synchrotron ra-diation for theanalysis of monazite giant halo inclusions in biotite inthe search for superheavy primordial elements. A curved mosaic graphite crystal was employed to both focus and monochromatize the synchrotron radiation beam. Pho-tons of energy 37 keV with a full width at half maximum (fwhm) of 0.4 keV were used. A flux of 15 X 1010 photons/(s mm2) was realized. The actual beam spot size was 0.64 mm2. Since 1981 a number of papershave been published re-garding the use of X-ray microprobes (2-5). In most cases, the synchroton white radiation beamhas been collimated by using vertical and horizontal slits or doubly curved crystals have been used to focus the radiation. Typical usable beam spot sizes attained are on the order of 700-2500 pm2. More recently Iida and Gohshi (6) have demonstrated the use of a reflection/transmission mirror combinationto focus and