骨电子探针发射微分析中钙和磷X射线产生的体积：蒙特卡罗模拟

Volumes from which calcium and phosphorus X-rays arise in electron probe emission microanalysis of bone: Monte Carlo simulation.

作者信息

Howell P G T, Boyde A

机构信息

Department of Prosthetic Dentistry, The Eastman Dental Institute, University College London, Gray's Inn Road, London WC1X 8LD, UK.

出版信息

Calcif Tissue Int. 2003 Jun;72(6):745-9. doi: 10.1007/s00223-002-2010-9.

DOI:10.1007/s00223-002-2010-9

PMID:14563004

Abstract

Monte Carlo simulations of trajectories for electrons with initial energy of 10 keV through 30 keV were used to map the 3D location of characteristic x-ray photon production for the elements C, P, and Ca until the electrons either escaped as backscattered electrons (BSE) or had insignificant energy. The x-ray production volumes for phosphorus slightly exceed those for calcium, but both greatly exceed the volume through which BSE travel prior to leaving the sample. The x-ray volumes are roughly hemispherical in shape, and the oblate spheroid from which BSE derive occupies only the upper third to half the volume of x-ray generation. Energy-dispersive x-ray emission microanalysis (EDX) may not be secure as a method for the quantitation of BSE images of bone in the scanning electron microscope (SEM). Ca:P elemental ratios from EDX analyses may also be imperfect.

摘要

利用蒙特卡罗模拟，对初始能量为10千电子伏特至30千电子伏特的电子轨迹进行了模拟，以绘制碳、磷和钙元素特征X射线光子产生的三维位置，直到电子以背散射电子（BSE）的形式逸出或能量变得微不足道。磷的X射线产生体积略超过钙的，但两者都大大超过了BSE在离开样品之前所经过的体积。X射线体积大致呈半球形，而BSE产生的扁球体仅占据X射线产生体积的上三分之一至一半。能量色散X射线发射微分析（EDX）作为扫描电子显微镜（SEM）中骨BSE图像定量分析方法可能并不可靠。EDX分析得出的钙磷元素比率也可能不完善。