منابع مشابه
Quasicrystals
The discretely diffracting aperiodic crystals termed quasicrystals, discovered at NBS in the early 1980s, have led to much interdisciplinary activity involving mainly materials science, physics, mathematics, and crystallography. It led to a new understanding of how atoms can arrange themselves, the role of periodicity in nature, and has created a new branch of crystallography.
متن کاملTwinning in cattle.
INTRODUCTION The biological efficiency of traditional systems of beef production is low due to the low reproductive rate and the high proportion of total energy which is required for maintenance of the breeding herd. Dickerson (1978) estimated that 56% of the total feed energy intake for adult and market cattle is required solely for body maintenance (the non-productive energy requirement rises...
متن کاملTwinning rates in Tamilnadu.
A prospective study of human reproduction was conducted in Tamilnadu State, South India, from 1969 to 1975. This paper reports twinning rates and relates these to maternal age, parity, and consanguinity. Birth weights and other dimensions at birth and infant mortality are also studied. The overall twinning rate was 1 in 115 births. Dizygotic twinning rates increased significantly with maternal ...
متن کاملDisclinations in quasicrystals.
The most significant feature in the transition from the quasicrystalline to the amorphous state is the loss of long-range bond-orientational order. Disclinations are candidates for elementary excitations which destroy angular correlations. Genera lizing the topological defect classification, we investigate point singularities in two-dimensional pentagonal quasicrystals and construct disclinatio...
متن کاملRhombellanic Crystals and Quasicrystals
Design of some crystal and quasicrystal networks, based on rhombellane tiling,is presented. [1,1,1]Propellane,is a synthesized organic molecule; its hydrogenated form, the bicyclo[1.1.1]pentane,may be represented by the complete bipartite graph K2,3 which is the smallest rhombellane. Topology of translational and radial structures involving rhombellanes is described in terms of vertex symbol, c...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Acta Crystallographica Section A Foundations and Advances
سال: 2015
ISSN: 2053-2733
DOI: 10.1107/s2053273315098368