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edX is a US for-profit online education platform owned by 2U since 2021. The platform's main focus is to manage a variety of offerings, including elite brand bootcamps. [3] edX was founded in May 2012 by the administrations of MIT and Harvard, [5] based on the MITx initiative, created by Piotr Mitros, Rafael Reif, and Anant Agarwal in 2011 at MIT.

能量散射X射线谱（Energy-dispersive X-ray spectroscopy，英文缩写有EDS、EDX、EDXS或XEDS），有时也被称作能量散射X射线分析（ energy dispersive X-ray analysis ，EDXA）或能量散射X射线微量分析（ energy dispersive X-ray microanalysis ，EDXMA）是一种用于元素分析和化学表征的分析手段。

edX是一个由麻省理工学院和哈佛大学创建的大规模开放在线课堂平台。 它给大众提供大学教育水平的在线课堂及 微碩士 學位。 两所大学在这个 非营利性 计划各资助三千万美元。

EDX是借助于分析试样发出的元素特征X射线波长和强度实现的， 根据不同元素特征X射线波长的不同来测定试样所含的元素。 通过对比不同元素谱线的强度可以测定试样中元素的含量。 通常EDX结合 电子显微镜 使用，可以对样品进行 微区成分分析。 常用的EDX探测器是硅渗锂探测器。 当特征 X射线光子 进入硅渗锂探测器后便将硅原子电离，产生若干 电子-空穴对，其数量与光子的能量成正比。 利用 偏压 收集这些电子空穴对，经过一系列 转换器 以后变成电压脉冲供给多 …

edX is the online learning destination co-founded by Harvard and MIT. The Open edX platform provides the learner-centric, massively scalable learning technology behind it. Originally envisioned for MOOCs, Open edX platform has evolved into one of the leading learning solutions catering to Higher Ed, enterprise, and government organizations alike.

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EDS分析是利用元素的特征X射线，而氢和氦原子只有K层电子，不能产生特征 X 射线，所以无法进行成分分析，锂(Li)和铍(Be)虽然能产生X射线，但产生的特征X射线波长太长，能量小，通常无法进行检测，目前元素分析元素范围一般从硼(Be)-铀(U)。