应用黑白相纸中银的测定，相对标准偏差为1.1%～1.6%，回收率为：97.7%～98.2%。
The method has been used to determine silver in photographical paper samples with the RSD of 1.1 % ~ 1.6 % and the recovery of 97.7 % ~ 98.2 % .
用白报纸把它包起来。普通黑白活页摄影相纸
Wrap it up in newspaper . black and white photographic sheet papers for general use
黑白相纸