Topological defects models

Now we study the effects of the dynamical processes of nonequilibrium phase transitions on domain growth and topological defects. The quench models describe such nonequilibrium processes, which can be... 

M. Trodden, A.-C. Davis, R. Brandenberger, Particle physics models, topological defects and electroweak baryogenesis. Phys. Lett. B 349, 131-136 (1995)... 

Introduces the bondonic phase-transition algorithm to model the topological defects on nanosystems by analytical and quantum simulation ... 

Very large GB systems (over 80,000 molecules) have also been recoitly studied to investigate some of the most distinctive features of liquid crystals topological defects [27,28], until now simulated only with lattice models [29]. In particular, the twist grain boundary phase in smectics [27] and the formation of a variety of defects in nematics by rapid quenching [28] have been examined. 

TEM techniques, the atomic stmcture of RGO was obtained very recently, as reported by Gomez-Navarro and co-workers. They described that the RGO sheets feature intact graphene islands of variable size between 3 and 6 nm, interspersed into defect areas dominated by clustered pentagons and heptagons. This result is in accordance to the model proposed by Lerf and co-workers, but also reveals the presence of a significant amount of topological defects for RGO. 

The description of a network structure is based on such parameters as chemical crosslink density and functionality, average chain length between crosslinks and length distribution of these chains, concentration of elastically active chains and structural defects like unreacted ends and elastically inactive cycles. However, many properties of a network depend not only on the above-mentioned characteristics but also on the order of the chemical crosslink connection — the network topology. So, the complete description of a network structure should include all these parameters. It is difficult to measure many of these characteristics experimentally and we must have an appropriate theory which could describe all these structural parameters on the basis of a physical model of network formation. At present, there are only two types of theoretical approaches which can describe the growth of network structures up to late post-gel stages of cure. One is based on tree-like models as developed by Dusek7 I0-26,1 The other uses computer-simulation of network structure on a lattice this model was developed by Topolkaraev, Berlin, Oshmyan 9,3l) (a review of the theoretical models may be found in Ref.7) and in this volume by Dusek). Both approaches are statistical and correlate well with experiments 6,7 9 10 13,26,31). They differ mainly mathematically. However, each of them emphasizes some different details of a network structure. 

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