density-functional theory is used to investigate sulfur dioxide physisorption inside and outside of single-wall carbon nanotube of (5,0) and (5,5). this study is conducted at b3lyp/6-31g* level of theory. sulfur dioxide molecule is studied with axis oriented parallel or perpendicular to the nanotube wall. both internal and external adsorption on nanotubes is increased with the angle of interact...

Studies of the modes of adsorption and the associated changes in electronic structures of renewable organic compounds are needed in order to understand the fundamentals behind surface reactions of catalysts for future energies. Using planewave density functional theory (DFT) calculations, the adsorption of ethanol on perfect and O-defected TiO(2) rutile (110) surfaces was examined. On both surf...

Nonspecific protein adsorption generally occurs on any solid surfaces and usually has adverse consequences. Adsorption of proteins onto a solid surface is believed to be the initial and controlling step in biofouling. Surfaces modified with end-tethered poly(ethylene glycol) (PEG) have been shown to be protein-resistant to some degree. In this study, the adsorption of β-casein and lysozyme was ...

Many experimental studies of protein deposition on solid surfaces involve alternating adsorption/desorption steps. In this paper, we investigate the effect of a desorption step (separating two adsorption steps) on the kinetics, the adsorbed-layer structure, and the saturation density. Our theoretical approach involves a density expansion of the pair distribution function and an application of a...

The adsorption of a number of amino acids on a defected single-walled carbon nanotube (SWCNT) isinvestigated by using the density-functional theory (DFT) calculations. The adsorption energies andequilibrium distances are calculated for various configurations such as amino acid attaching to defectsites heptagon, pentagon and hexagon in defective tube and also for several molecular orientationswi...

We report the first six-dimensional quantum dynamical calculations of dissociative adsorption and associative desorption. Using a potential energy surface obtained by density functional theory calculations, we show that the initial decrease of the sticking probability with increasing kinetic energy in the system H2/Pd(100), which is usually attributed to the existence of a molecular adsorption ...

The effects of chemical and structural surface heterogeneity on the CH4 adsorption behaviour on microporous carbons have been investigated using a hybrid theoretical approach, including the use of density functional theory (DFT), molecular dynamics (MD), and grand canonical Monte Carlo (GCMC) simulations. Bader charge analysis is first performed to analyze the surface atomic partial charges. Th...

Simulated adsorption isotherms for water in UiO-66 illustrate that defects in the form of missing linkers make this MOF more hydrophilic. Heats of adsorption and density plots further confirm the effect of defects on adsorption of water in UiO-66 at low loadings. In addition, water and CO2 isotherms indicate that not only the amount of defects but their locations within the material affect the ...

The adsorption of proteins, in particular fibronectin (Fn), was studied on poly(ethylene glycol) (PEG, 5kDa)-grafted surfaces, and was correlated with the adhesion behaviors of smooth muscle cells (SMCs). The PEG molecules were covalently grafted on aldehyde-activated substrates with different densities of amino groups. The thickness of PEG layer increased nearly 10 fold in a hydrated state, re...

We compute the free energy for two rows of localized adsorption sites embedded in a two dimensional one-component plasma with neutralizing background density ρ. The interaction energy between the adsorption sites is repulsive. We also compute the average occupation number of the adsorption sites and compare it to the result for a single row of sites. The exact result indicates that the discreti...