“methods of sampling”的概念、定义、翻译、参考文献-科学参考

单词	methods of sampling
释义	methods of sampling Encyclopedia 理学【试剂和试样】释 methods of sampling试样准备包括取样和试样制备两步。前者是指从大量物料（分析对象的总体）中取得其中有代表性的一小部分，即在误差允许范围内，这一小部分试样应能代表大量物料的组成。后者是把按一定程序取得的仍然颗粒较大的试样，经过破碎、缩分、研磨、过筛等步骤，制备成适合于作分析用的试样。
随便看	principal category principal cell principal character principal circle principal class principal coefficient of contraction principal cohomology class principal coincidence curve principal component principal component analysis principal component analysis and singular value decomposition principal component analysis (PCA) principal component analysis, PCA principal component analysis,PCA principal component clustering principal component discrimination principal component estimate principal component estimate of the coefficients in linear regression model principal component estimation principal component of order p principal component regression principal component regression method principal component regression method (PCR) principal component regression spectrophotometry principal components

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