在分析工作中,常常遇到一些试样有筛上筛下之分,其计算繁复,很费时间,计算公式如下: M％=M％_上+M％_下G_下/G_上+G_下……(1)其中M为某欲测元素的含量 M_上为筛上含量 G_上为筛上试样量(克) M_下为筛下含量 G_下为筛下试样量(克) 通过实践我们将上式进行了如下推演:将式(1)分子加上M％_上G_下-M％_上G_下其值应不变,上式变为: In the analysis of work, often encountered some samples have sieve under the sieve points, the calculation is complicated and time-consuming, the formula is as follows: M% = M% _ on + M% _ under G_ next / G_ on + G_ (1) where M is the content of a desired element M_ is the content of the sieve G_ is the amount of the sample on the sieve (g) M_ is the content of the sieve G_ is the size of the sieve The amount of sample (g) We practice the above formula was deduced as follows: The formula (1) molecules plus M% _ on G_ under-M% _ on G_ its value should not change, the above formula becomes :