牙釉质黏接面的处理常采用30%~60%磷酸液处理1分钟。( )
参考答案:错
解析: 牙釉质黏接面的处理常用30%~50%磷酸液处理1分钟。
He eats __________ food, so he is __________ fat.[ ]
A. much too; too much
B. too much; much too
C. much too; the many
D. too much; too many
活性炭按助滤剂的作用原理分属于()类。
A、表面活性型
B、絮凝剂型
C、颗粒型
D、非离子表面活性型