十面体的

V-shape grooves exist in twinned crystal planes of fivefold twin. As for thermodynamics and kinetics, the grooves are helpful for diamond grains of fivefold twin to grow.

正二十面体和正十面体颗粒都是"五重孪晶"结构，在颗粒表面上与五重孪晶面对应的区域形成V-形槽，这种V-形槽对五重孪晶金刚石颗粒的长大有热力学和动力学的有利作用。

The morphologies of diamond include cube, cuboid, octahedron, cuboctahedron, twinned cuboctahedron, decahedron and icosahedron and ball-like diamond using SEM observation. The formation condition of the grains is discussed.

用SEM观察CVD金刚石晶粒形态主要有立方体、长方体、八面体、立方八面体、李晶八面体、十面体和二十面体颗粒以及球形金刚石，讨论了晶粒的形成条件。

Our results show that the duality of self-dual tetrahedral link is "trivial", and the duality of hexahedral and octahedral link as well as dodecahedral and icosahedral link are "nontrivial".

从构型角度考虑，四面体链环的自对偶是"平凡"的，六面体链环和八面体链环，十二面体和二十面体链环的对偶是"非平凡"的。

Goldberg got a class of polyhedra which are icosahedral symmetry by appending hexagons on regular dodecahedron by rule in 1937. They are called Goldberg polyhedra which provides a new approach for polyhedral molecule design.

1937年，数学家Goldberg通过在正十二面体上有规律地添加六边形面得到一类具有二十面体对称性的多面体，即Goldberg多面体。

Icosehedral quasicrystal, showing icosahedral point group symmetry and quasi-periodic order along three directions, has been intensively studied.

二十面体准晶是目前研究最广泛的准晶之，它具有二十面体点群对称性，属于三维准晶，就是说其原子在三维上都是准周期分布的。

Similar conclusion will be right for other multiply twinned clusters, such asdecahedra, truncated decahedra and Marks decahedra.

同样的结论还可以应用到其它的具有多重孪晶结构团簇中去，如：十面体，截边的十面体和Marks十面体。

In contrast to ordinary liquid and amorphous alloys, the number of 1551 bonds related to the icosahedral structure becomes very smaller with the decrease of temperature,but the numbers of 1311,1301,1201 bonds related to the rhombohedral structure are increased remarkably.

结果表明，与通常液态及非晶态金属相反，随着温度降低，与二十面体相关的1551键型数越来越少，而与菱面体相关的1311，1301和1201键型数目显著增加，最后形成以菱面体结构单元为主的非晶态结构。

The continuing of the process produces icosahedra of even higher orders (a2, a3,…,an).

实质上，这一模型可以看成正二十面体与正十二面体共轭生成的结果。

The truncated icosahedra have been prepared for the first time by prolonging the reaction time to 4 h.The XRD,SEM,TEM and Uv-vis technologies confirm the high shape difference between icosahedral gold nanocrystals and their truncated forms.

通过延长反应时间合成了一种类似足球的新型金纳米粒子—截角二十面体，研究结果表明，该粒子由二十个六边形和十二个五边形组成，截角面是{100}面。

Our results show that the duality of self-dual tetrahedral link is "trivial", and the duality of hexahedral and octahedral link as well as dodecahedral and icosahedral link are "nontrivial".

从构型角度考虑，四面体链环的自对偶是&平凡&的，六面体链环和八面体链环，十二面体和二十面体链环的对偶是&非平凡&的。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐