It is an aggregate of four polar bonds, but they are symmetry arranged in space.
这是四个极性键,按空间对称聚集的结果。
2
In this paper, the symmetry of curved lined given by parametric equation and polar coordinates equation is discussed and the sufficient conditions are given.
本文讨论了参数方程和极坐标方程表示的曲线的对称性,给出了判定这两种曲线的对称性的充分条件。
3
The displacement solution is constructed by applying the symmetry of scattering of SH-wave and the method of multi-polar coordinate system.