标签：substance - 华人论坛

在加拿大 我们是做箱包的，客户问一款电脑包 Do you have substance compliance test results for materials used in 65214 （这个数字是我们产品型号） 请教各位，客户到底是要什么呢？ 谢谢！！！！！！！！ 评...华人论坛

在加拿大 A distinct substance made of two or more elements according to a proportion determined by weight. Its composition is expressed by means of a chemical formula, which lists the various elements present as well as the relative number of each el...华人论坛