We calculate first-principles interaction energies between substitutional solutes and oxygen interstitials in a-titanium and predict the effect of solutes on oxygen diffusion from those interactions. Interaction between 45 solutes across the periodic table and three oxygen interstitial sites are calculated with density-functional theory. The interaction energies show distinct trends across the ...

Infection of polarized MDCK epithelial layers by Salmonella enterica serovar Typhimurium is accompanied by increased tight junction permeability and by contraction of perijunctional actinomyosin. We localized dysfunctional tight junctions in serovar Typhimurium-infected MDCK layers by imaging apical-basolateral intramembrane diffusion of fluorescent lipid and found that loss of the apical-basol...

a r t i c l e i n f o Scanning tunneling microscopy combined with molecular dynamics simulations reveals a dislocation-mediated island diffusion mechanism for Cu on Ag(111), a highly mismatched system. Cluster motion is tracked with atomic precision at multiple temperatures and diffusion barriers and prefactors are determined from direct measurements of hop rates. The barrier to nucleate a disl...

Biochemical reaction networks consisting of coupled enzymes connect substrate signaling events with biological function. Substrates involved in these reactions can be strongly influenced by diffusion "barriers" arising from impenetrable cellular structures and macromolecules, as well as interactions with biomolecules, especially within crowded environments. For diffusion-influenced reactions, t...

We perform density-functional theory ~DFT! calculations of carbon dissolution and diffusion in iron, the latter being a typical example of interstitial diffusion. The Kohn-Sham equations are solved with periodic boundary conditions and within the projector-augmented-wave formalism, using the generalized gradient approximation for electron exchange and correlation. With the solution enthalpy as ...

The electrochemical cell offers the promise of enabling controlled alteration of the morphology and islanding phenomena on metallic surfaces. Different diffusion processes near step and island edges are known to profoundly affect the growth mode, island sizes, island shapes and step morphology. Using the surface-embedded-atom-model (SEAM) modified for the electrolytic environment, we calculate ...

We demonstrate automated generation of diffusion databases from high-throughput density functional theory (DFT) calculations. A total of more than 230 dilute solute diffusion systems in Mg, Al, Cu, Ni, Pd, and Pt host lattices have been determined using multi-frequency diffusion models. We apply a correction method for solute diffusion in alloys using experimental and simulated values of host s...

Ethylene Vinyl Alcohol (EVOH) is a random copolymer of ethylene and vinyl alcohol, commonly used as a barrier to hydrocarbons in automotive fuel systems and agricultural pesticide and herbicide solvents. EVOH provides extremely high resistance to the migration of gases and volatile organic compounds (VOC’s). The incorporation of EVOH in radon resistant new construction has the potential to dram...

Spin tunnel junctions fabricated with one interposed Fe–FeOx layer between the Al2O3 barrier and the top CoFe pinned electrode show large tunneling magnetoresistance ~TMR! ~40%! for anneals up to 380 °C. The annealing temperature TTMR * , where maximum TMR occurs, increases with the inserted Fe–FeOx layer thickness. For samples with thicker inserted layer, the pinned layer moment ~which usually...