Significance Diffusion is the primary process in practical multidisciplinary areas such as separation and catalysis. Transportation usually positively correlated with temperature due to thermal motion. We show here an anomalous phenomenon wherein a higher effectively slows diffusion for linear-chain hydrocarbon molecules under confinement. Such obstruction results from novel mechanism of “therm...

In order to study the mechanisms limiting the topological chain confinement in polymer melts, we have performed neutron-spin-echo investigations of the single-chain dynamic-structure factor from polyethylene melts over a large range of chain lengths. While at high molecular weight the reptation model is corroborated, a systematic loosening of the confinement with decreasing chain length is foun...

We present transport measurements along the least conducting (c) direction of the organic superconductor (TMTSF)2ClO4 performed under an accurately aligned magnetic field in the low temperature regime. The experimental results reveal a two-dimensional confinement of the carriers in the (a,b) planes which is governed by the magnetic field component along the b ′ direction. This 2-D confinement i...

Dendrimers are a novel class of nanometric-size macromolecules with a regular tree-dimensional like array of branch units [1,2]. Their synthetic availability in a wide range of sizes combined with their peculiar architecture makes them versatile building blocks for a wide range of potential applications [3]. Some years ago, Meijer and co-workers reported that the modification of terminal amine ...

In thermal frontal polymerization, the interplay between heat diffusion and Arrhenius type reaction kinetics gives rise to a propagating reactive front that is effectively sustained through a system positive feedback mechanism. We seek to understand how spatial confinement affects the system dynamics and overall polymerization kinetics. We find that with increasing confinement of the system, th...

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We propose a semiconductor microcavity structure in which the cavity layer is entirely both optically and electronically active. Optical spectra at normal incidence are studied theoretically, showing the drastic effects of the cavity polariton mode splitting and of the Bragg mirror confinement.

Thermal conductivity of thin silicon nanowires (1.4-8.3 nm) including the realistic crystalline structures and surface reconstruction effects is investigated using direct molecular dynamics simulations with Stillinger-Weber potential for Si-Si interactions. Thermal conductivity as a function of decreasing nanowire diameter shows an expected decrease due to increased surface scattering effects. ...