方法: 用溴代及胺化反应合成了四甲基吡嗪衍生物.METHODS: The target compound was prepared by the bromination and amination reaction.用溴—甲醇溶解Al_2O_3, 其回收率在91%以上.If Al 2 O 3 is dissolved by Br 2 - CH 3 OH, its Recovery rate is above 91 %.用溴比用氯时产出率...
当然，这两家公司间非常明显地产生了巨大的协同效应。Of course, there'squite obviously a lot of synergy between the two companies.各学校将协同分享最佳方案。Schools will work together to share best practice.大多数维基网站属于协同工作网站。Most wikis are collaborative websi...