The half-metallocene of the elements V, Nb and Ta in VB group could be used in the polymerization of olefin to prepare polymer with rather narrow molecular weight distribution (1.05).
VB族元素钒、铌、钽的单茂金属化合物作为烯烃催化剂可得到分子量分布相当窄（1.05）的聚烯烃；
The elements of group V A include three nonmetals — nitrogen, phosphorus, and arsenic—and two metals — antimony and bismuth.
集团外语由一个非金属、碳、两个非金属等、硅和锗，和两个金属、锡、铅。
The elements of group V A include three nonmetals — nitrogen, phosphorus, and arsenic—and two metals — antimony and bismuth.
集团外语由一个非金属、碳、两个非金属等、硅和锗，和两个金属、锡、铅。
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