Indentation tests at scales on the order of one micron have shown that measured hardness increases signi_cantly with decreasing indent size\ a trend at odds with the size!independence implied by conventional plasticity theory[ In this paper\ strain gradient plasticity theory is used to model materials undergoing small!scale indentations[ Finite element implementation of the theory as it pertain...

Nanotechnology is one of the pillars of human life in the future. This technology is growing fast and many scientists work in this field. The behavior of materials in nano size varies with that in macro dimension. Therefore scientists have presented various theories for examining the behavior of materials in nano-scale. Accordingly, mechanical behavior of nano-plates, nanotubes nano-beams and n...

Microtubules are used as targets for anticancer drugs due to their crucial role in the process of mitosis. Recent studies show that carbon nanotubes (CNTs) can be classified as microtubule-stabilizing agents as they interact with protein microtubules (MTs), leading to interference in the mitosis process. CNTs hold a substantial promising application in cancer therapy in conjunction with other c...

Neck retardation in stretching of ductile materials is promoted by strain hardening, strain-rate hardening and inertia. Retardation is usually beneficial because necking is often the precursor to ductile failure. The interaction of material behavior and inertia in necking retardation is complicated, in part, because necking is highly nonlinear but also because the mathematical character of the ...

importance of covalent bonded two-dimensional monolayer nanostructures and also hydrocarbons is undeniably responsible for creation of new fascinating materials like polyphenylene polymer, a hydrocarbon super honeycomb network, so-called porous graphene. the mechanical properties of porous graphene such as its young’s modulus, poisson’s ratio and the bulk modulus as the determinative properties...

It has not been a simple matter to obtain a sound extension of the classical J2 flow theory of plasticity that incorporates a dependence on plastic strain gradients and that is capable of capturing size-dependent behaviour of metals at the micron scale. Two classes of basic extensions of classical J2 theory have been proposed: one with increments in higher order stresses related to increments o...

The preferred body temperature of ectotherms is typically inferred from the observed distribution of body temperatures in a laboratory thermal gradient. For very small organisms, however, that observed distribution might misrepresent true thermal preferences. Tiny ectotherms have limited thermal inertia, and so their body temperature and speed of movement will vary with their position along the...