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食品样品制备的前处理

发布日期:2022-07-02

食品样品制备的前处理

试题解析

样品制备

样品制备在透射电子显微分析技术中占有相当重要的位置。由透射电镜的工作原理可知,供透射电镜分析的样品必须对电子束是透明的,通常样品观察区域的厚度以控制在约100~200 nm为宜。此外,所制得的样品还必须具有代表性以真实反映所分析材料的某些特征,因此,样品制备时不可影响这些特征,如已产生影响则必须知道影响的方式和程度。透射电镜样品制备是一个涉及面很广的题目,方法也很多。选择哪种方法,则取决于材料的类型和所要获取的信息。透射电镜样品可分为间接样品和直接样品.本章仅介绍应用较广的复型、电解双喷、离子薄化等样品制备技术。

中文名
样品制备
对应
技术
对象
透射电子显微
属性
100~200 nm

前处理

前处理是2005年全国科学技术名词审定委员会公布的航天科学技术名词。

中文名
前处理
所属学科
航天科学技术
审定机构
全国科学技术名词审定委员会
外文名
pre-processing
公布年度
2005年

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