In addition, non-coated paper in high-humidity environment of sulfide, chemical pulp and fill applicatron dottle out acid melted, making of gold and silver monlchamus nigrescent who lose their luster.
此外,否

在矮湿度
境况下,化学
浆
硫化物
及增添
洋
磕酸矾土感化,也会使


金、银不朱发黑而获得光华度。



