The causes of tarnishing gold and silver - plated connectors were studied respectively.分别探讨了接插件镀金和镀银层变色的原因.Bright tin electrodeposits on copper wire are susceptible to tarnishing.铜线材经光亮镀锡后易产生腐蚀变色.Do they not realize thei...
此矩阵借方程缩聚.This matrix is condensed by the equation.缩聚催化剂会对聚酯后加工性能产生不良影响.Polycondensation catalyst may has bad effect on polyester afterprocessing properties.用糠醇和糠醛缩聚制备了新型呋喃树脂.A novel furan resin was synthesized by polycon...
In regard to animals, Diphyodont evolved into Reptilia, which evolved into mammals.动物是由两栖进化为爬虫, 再进化为哺乳类.Bears are asocial, secretive animals ( David Graber )熊是不合群 、 孤僻的动物 ( 戴维格雷伯 )Trauma is the most common cause of epist...