六方柱

Quartz is commonly found as a six-sided, prism-shaped crystal topped by pyramid-like form, while calcite usually shows a crystal form of rhombohedron.

石英通常呈六方柱，顶上带有双锥的晶形，而方解石却常以菱形六面体形式出现。

Based on the observation of atomic force microscopy, the etching morphology of faces and sections with different crystallographic significance on α-quartz has been studied. The etching morphology on the natural crystal faces hexagonal prism faces (1010 and 01(average10, rhombohedron positive form face 10(average11, rhombohedron negative form face 01(average11 and the sections between any of the two crystal faces has been observed. It is shown that the etching pit on the same simple form has the same shape, while the orientation of the etching pits can be different. Different simple forms have different shapes of etching pits and the shapes of etching pits on positive form and negative form of the same simple form are also different.

通过对α-石英自然晶面六方柱面10(平均值10和01(平均值10、菱面体正形面10(平均值11与菱面体负形面01(平均值11、以及介于上述自然晶面之间的切面进行腐蚀形貌的观察研究发现，石英晶体同种单形的晶面腐蚀坑形态相同，但方位可以有变化，不同单形的晶面腐蚀坑形态不同；同一单形的正形与负形腐蚀坑形状不同；蚀坑形态能够反映晶体的对称性。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。