采用中心柱倒装法组装立式储罐,当公称容积小于300米3时采用()中心柱,公称容积在400~500米3时采用()中心柱。
参考答案:φ159×6;φ219×6
___________to be the greatest writer of plays in the English-speaking world, Williams Shakespeare is more famous than he was in his own lifetime.
A.Considered
B.To be considered
C.Having considered
D.Considering
同周期的X,Y,Z3种元素,已知其最高价氧化物对应水化物的酸性强弱顺序是:
HXO4>H2YO4>H3ZO4,则 下列各判断正确的是[ ]
A.原子半径:X>Y>Z
B.单质非金属性:X>Y>Z
C.气态氢化物的稳定性:X<Y<Z
D.原子序数:X>Y>Z