A fast, nondestructive method based on the determination of local concentration profiles in the polymer thickness with Raman microspectroscopy is presented here. It was used to assess the diffusivity of a model molecule (p-terphenyl) in amorphous polystyrene films at 95 C (2.386 1.083 10 m/s). This methodology was validated by comparison with a more classical destructive approach based on the m...

Charge transport in 20–30-Å-thick Bi films is studied by scanning tunneling potentiometry at room temperature. Deposition at T5140 K onto InP-based multilayer substrates leads to flat and continuous films that are subjected to a lateral current density of up to 8310 A/cm. We find that scattering at surface defects and grain boundaries gives rise to discontinuities in the local electrochemical p...

The properties of the cysteines in the pBR322-encoded tetracycline resistance protein have been examined. Cysteines are important but not essential for tetracycline transport activity. None of the cysteines reacted with biotin maleimide, suggesting that they are shielded from the aqueous phase or reside in a negatively charged local environment.

Ozone transport has an important effect on the local ozone concentrations. In this paper, we model the California State and the Eastern States of America ozone transport as complex networks to understand large-scale dynamics. California has a complex ozone transport due to geomorphology and is divided into 15 air basins to manage air pollution. Unlike California, the ozone transport in the East...

[1] Water-rock interactions within variable aperture fractures can lead to dissolution of fracture surfaces and local alteration of fracture apertures, potentially transforming the transport properties of fractures over time. Because fractures often provide dominant pathways for subsurface flow and transport, developing models that effectively quantify the role of dissolution on changing transp...

We propose a fast and versatile algorithm to calculate local and transport properties such as conductance, shot noise, local density of state, and local currents in mesoscopic quantum systems. Within the nonequilibrium Green function formalism, we generalize the recursive Green function technique to tackle multiterminal devices with arbitrary geometries. We apply our method to analyze two recen...

The vortex state thermal and transport properties of the high T c copper oxides can be understood in a d-wave gap model and are dominated by the extended quasiparticle states that exist along the nodal directions in momentum space. The Doppler shift on these states due to the circulating supercurrents around the vortex core, introduces new van Hove ridges into the energy dependent local density...

Carrier transport was investigated in two different types of ultra-thin silicon films, polycrystalline silicon (poly-Si) films with large grains > 20 nm in size and hydrogenated nanocrystalline silicon (nc-Si:H) films with grains 4 nm – 8 nm in size. It was found that there were local non-uniformities in grain boundary potential barriers in both types of films. Single-electron charging effects ...