This is not meant to delimit what approaches social researchers can adopt.这并不是为了限制社会研究人员所能采用的方法。The group which they delimit are called natural groups.由此划分出的类群称为自然类群.to delimit the epidemic area and the protection area划定...
Methods: α - Bromo - 4 - benzyloxy acetophenone is synthesized with 4 - hydroxy acetophenone and bromonium as materials and methanol as solvent.方法: 以甲醇为溶剂,以对羟基苯乙酮和溴为原料制备了α - 溴-4-苄氧苯基苯乙酮.Thus , this reduced temperature of...