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Based on the concepts of fractal super fibers, the (3, 9+2)-circle and (9+2, 3)-circle binary fractal sets are abstracted form such prototypes as wool fibers and human hairs, with the (3)-circle and the (9+2)-circle fractal sets as subsets. As far as the (9+2) topological patterns are concerned, the following propositions are proved: The (9+2) topological patterns accurately exist, but are not unique. Their total number is 9. Among them, only two are allotropes. In other words, among the nine topological patterns, only two are independent (or fundamental). Besides, we demonstrate that the (3, 9+2)-circle and (9+2, 3)-circle fractal sets are golden ones with symmetry breaking. 相似文献
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A structurally stable two-dimensional carbon allotrope principles calculations. This allotrope can be formed of graphene is studied theoretically based on the first- by inserting acetylene and diacetylene fragments into β-graphyne. The calculations on structure and electronic energy spectra show that the carbon Kagome lattice is a structurally stable semimetal with the Dirac cones below the Fermi surface, in contrast to the Dirac points at the Fermi surface in intrinsic graphene. 相似文献
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依据2005年IUPAC颁布的无机物命名法,列举了同素异形体、同核多原子阳离子、同核多原子阴离子、异核多原子阴离子以及含氧酸等常见无机物的新名称,对新命名法的特点进行了分析与总结,着重介绍了加成命名法。 相似文献
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球状碳——碳的第三种同素异形体 总被引:1,自引:0,他引:1
本文综述了球状碳(富勒烯)的发现,制备,结构,化学性质及芳香性,以及配合物等方面的最新的研究进展。 相似文献
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讨论了溶质和溶剂的极性与溶解度的关系;分子所含的极性基团与溶解度的关系;同素异形体和同分异构体的溶解性;在同一溶剂中2种溶质对溶解性的相互影响;溶质在混合溶剂中的溶解性;两亲(亲水、亲脂)溶质的溶解性;金属间的相互溶解。 相似文献
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基于密度泛函理论,本文提出了一种新的硅同素异形体(C2-Si).根据弹性常数和声子谱研究了C2-Si的力学稳定性和动力学稳定性.根据体积模量与剪切模量的比值,表明了C2-Si在环境压力下具有延展性;与Si64、Si96、I4/mmm和h-Si6相比,C2-Si的脆性较小.在Heyd-Scuseria-Ernzerhof杂化函数中,C2-Si是一种间接窄带隙半导体,C2-Si的带隙仅为0.716 eV,约为c-Si的三分之二.通过C2-Si的杨氏模量、剪切模量和泊松比三维空间分布中的最大值和最小值之比来表征其各向异性.此外,通过不同晶面的杨氏模量、剪切模量和泊松比的二维图分析不同晶面的各向异性.在十多种硅同素异形体中,C2-Si对可见光的吸收能力最强. 相似文献