查询词典 icosahedra

Our results show that, for all the systems considered, icosahedra are favored at small sizes, and then the decahedra.

结果表明：对于小团簇，Ih结构占优势，其次是Dh结构。

Using atomic bond-type index method and cluster type index method, it has been found that during the microstructure transition processes the forming of icosahedra and its defective structures related to the increasing 1551 bond-type plays a remarkable role.

采用原子键型和原子团簇类型指数法，发现在其微观结构的转变过程中，与不断增加的1551键型密切相关的二十面体及其缺陷结构的形成起了非常突出的作用。

At last a single crystal of the ν-AlCrFe phase was found and the structure was determined by the combination of direct methods and high resolution electron microscopy. The structure contains a large quantity of slightly distorted icosahedra and the connection among them was analyzed.

利用单晶X射线衍射技术，结合高分辨电子显微学的研究结果，最终测定了ν-AlCrFe相的晶体结构，并对其中的二十面体的连接情况进行了分析。

When citrate ions were introduced to manipulate the nucleation and growth process, star-shaped icosahedra and nanorods with pentagram cross-sections were obtained.

通过向溶液中引入柠檬酸离子调控纳米颗粒的成核与生长过程，我们首次合成出了星状钯二十面体和截面为五角星形的钯纳米棒。

When citrate ions were introduced to manipulate the nucleation and growth process, star-shaped icosahedra and nanorods with pentagram cross-sections were obtained.

通过向溶液中引入柠檬酸离子调控纳米颗粒的成核与生长过程，首次合成出了星状钯二十面体和截面为五角星形的钯纳米棒。

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 numbers of clusters made up of 1551 and 1541 bonded pairs representing the non-crystal structure occupy predominate position and the small numbers of clusters made up of 1431, 1661 and 1441 bonded pairs coexist in the non-crystal system at 4×10〓K/s cooling rate, thus there exist a large number of icosahedra clusters in the non-crystal system. The numbers of clusters made up of 1421 bonded pairs corresponding to the fcc-like structure occupy predominate position and the small numbers of clusters made up of 1422 and 1551 bonded pairs coexist in the crystal system during the 4×10〓K/s cooling process, thus the system can form the regular fcc-like structure.

在4×10〓K/s的冷速下，标征体系非晶结构的五重对称键型1551和1541所形成的小团簇数量在非晶体系中占主导位置，同时还存在少量的1431、1441和1661等其它键型形成的小团簇，这样，体系中含有大量的二十面体团簇结构；在4×10〓K/s的冷速下，标征面心立方结构的1421键型所形成的小团簇数量在晶体中占第一位，同时还存在一定量的1422、1441和1661等其它类型的键对所形成的团簇，体系最终形成面心立方结构。

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。

The growth of truncated icosahedra could be induced and maintained through interplay of following processes:the～50 nm multiple twinned seeds were generated; shape and size focused by Ostwald ripening,then oxidativly etched and preferentially grew on the {100} face.Oxidative etching plays an important role in the formation of gold nanocrystals on hydrothermal condition.

对二十面体金纳米粒子及截角二十面体的生长机理进行了探讨，考察了不同刻蚀程度对金纳米粒子的形态影响，研究结果表明，增强体系刻蚀程度有利于单晶的生长，减弱刻蚀程度有利于孪晶的生长。

A systematic analysis of the icosahedral hierarchic structure in the 3D icosahedral quasicrystal and its approximants have been made. There is an icosahedron at the center surrounded by 12 icosahedra. If two neighboring icosahedra are vertex-sharing, the multi-shell Mackay cluster consisting of 127 atoms will form. If two neighboring icosahedra penetrate into each other, the multi-shell Samson-Bergman-Pauling cluster consisting of 137 atoms will form.

系统地分析了三维二十面体准晶的近似晶体相中具有二十面体对称的等级结构，中心1个二十面体，周边12个二十面体，如两个相邻二十面体共顶点连接，得出的是由127个原子构成的Mackay球形原子簇；如两个二十面体互相穿插，得出的是由137个原子构成的Samson-Bergman-Pauling球形原子簇。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。