We use of colorimetric phenol reagent and formaldehyde measurement devices for measuring formaldehyde, the accuracy of the measurement results can reach nominal 5% of the device.
采用酚试剂比色法并合理使用甲醛测量装置对甲醛含量进行了测定，测量结果的精度能够达到装置标称的5%。
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This article will introduce the measurement of the social variables, the transform of nominal level variable and ordinal level variable and the regression analysis of...