The formation of grain boundaries (GBs) in graphene films is both fundamentally interesting and practically important for many applications. A GB in graphene is known as a linear defect and is formed during the coalescence of two single crystalline graphene domains. The covalent binding between domains is broadly known as the mechanism of GB formation during graphene chemical vapor deposition (...

Control over the film-substrate interaction is key to the exploitation of graphene's unique electronic properties. Typically, a buffer layer is irreversibly intercalated "from above" to ensure decoupling. For graphene/Ni(111) we instead tune the film interaction "from below". By temperature controlling the formation/dissolution of a carbide layer under rotated graphene domains, we reversibly sw...

We investigate the interaction of a carbon nanotube with a graphite substrate, using an interlayer potential that explicitly treats the registry dependence of the interaction. The carbon-carbon bond lengths in nanotubes differ slightly from those in flat graphite, so that the naively commensurate angular orientations for the tube with respect to the substrate lattice are destroyed. The interact...

Using the model of interaction between two-level systems (TLS) and strain fields introduced in Phys. Rev. B 75, 064202 (2007), we calculate the TLS-TLS interaction. We particularize our calculations to amorphous materials and analyze the dependence of the interaction Hamiltonian on the orientations of the two TLSs and of the direction that connects them. Assuming isotropic distribution of the T...

The interaction between single-walled carbon nanotubes (SWNTs) and graphene were studied with first-principles calculations. Both SWNTs and single-layer graphene (SLG) or double-layer graphene (DLG) display more remarkable deformations with the increase of SWNT diameter, which implies a stronger interaction between SWNTs and graphene. Besides, in DLG, deformation of the upper-layer graphene is ...

Thermodynamics with two dividing surfaces is used to investigate the quasi-liquid layer on a crystal surface by regarding it as a thin liquid layer. The following thermodynamic quantities: chemical potential, vapour pressure, pressure tensor components and disjoining pressure of the layer are considered and relations between them are derived. The dependences of these quantities on the layer thi...

We propose a framework for building deadlock-free systems from deadlock-free components. The framework is based on a methodology for the layered construction of systems by superposing three layers. A layer of components, an interaction model and a restriction layer. The interaction model specifies the possible interactions between components. The restriction layer restricts the behavior of the ...

This study demonstrates that carbohydrates play an essential role in sperm-egg interactions in birds. Sperm-egg interaction was measured in vitro as the ability of spermatozoa to hydrolyse a small hole in the inner perivitelline layer, the equivalent of the mammalian zona pellucida. Preincubation with Triticum vulgaris lectin (WGA) and succinyl-WGA (S-WGA) at 10 microgram ml(-1) resulted in com...

this study aimed to investigate the effect of animal grazing on soil seed bank characteristics in the northern slopes of alborz. for this purpose, soil seed bank characteristics were compared between grazed and ungrazed areas. therefore, four transects perpendicular to the sides of exclosure inside and outside of it were established. then soil samples were collected within 28 plots inside and 2...

large size direct shear tests (i.e.300 x 300mm) were conducted to investigate the interaction between clay reinforced with geogrids embedded in thin layers of sand. test results for the clay, sand, clay-sand, clay-geogrid, sandgeogrid and clay-sand-geogrid are discussed. thin layers of sand including 4, 6, 8, 10, 12 and 14mm were used to increase the interaction between the clay and the geogrid...