【简答题】某一引发体系引发聚合时有如下特征:(1)加水有阻聚作用;(2)溶剂极性增加,聚合速率加快;(3)分子量随温度升高而下降;(4)聚合速率随温度升高而下降;(5)引发St(MI)-MMA(M2)共聚时,r 1 <1、r 2 >1。 判断这一聚合是按自由基、阳离子还是阴离子聚合机理进行的?理由是什么?
【简答题】What is the meaning of 'to skip lunch' in Paragraph Three?
【单选题】What is Skip's favorite food?
【简答题】自由基聚合的机理特征( )、( )、( )?
【简答题】s__________ v 设想,推测;假定
【简答题】通过市场采购资源的组织方式,主要有 ( ) 采购和 ( ) 采购两种方式。
【单选题】下列慢性肾衰竭患者的治疗措施中,其作用是纠正酸中毒,又防止手足抽搐的是
【单选题】What can be inferred about the professor's opinion?
A.
He is strongly in favor of the impact hypothesis.
B.
He does not believe that mass extinctions happened.
C.
He thinks that mass extinctions were important to evolution.
D.
He views mass extinction as a preventable occurrence.
【判断题】自由基聚合的机理特征是慢引发、快增长、速终止