Methane adsorption on positively charged aggregates of C60 is investigated by both mass spectrometry and computer simulations. Calculated adsorption energies of 118-281 meV are in the optimal range for high-density storage of natural gas. Groove sites, dimple sites, and the first complete adsorption shells are identified experimentally and confirmed by molecular dynamics simulations, using a ne...

We investigated the adsorption of a single atom, hydrogen and aluminum, on single-wall carbon nanotubes from first principles. The adsorption is exothermic, and the associated binding energy varies inversely as the radius of the zigzag tube. We found that the adsorption of a single atom and related properties can be modified continuously and reversibly by the external radial deformation. The bi...

The adsorption of a monolayer of V on idealized Feand oxygen-terminated hematite (0001) surfaces and subsequent oxidation under atomic O adsorption are studied by density functional theory. Theoretical results are compared with X-ray surface standing wave and X-ray photoelectron spectroscopic measurements, and interpreted in the light of data on sub-monolayer coverages. Near-surface Fe reductio...

In the environment, two main sources of heavy metals are natural backgrounds derived from parent rocks and anthropogenic contamination including mineral industrial wastes, tailing damps of sulfide mines, agrochemicals, and other outputs of industrial activities and factories. In this work, the physico-chemical aspects of the magnetic Nano- mineral surfaces are studied in contrast to acid mine d...

Density functional theory is used to calculate the adsorption of Ca adatoms on a MgO 100 surface. The Ca monomer binds preferentially to the oxygen site on the terrace with an adsorption energy of 0.84 eV and diffuses by hopping to a nearest neighboring oxygen site with a barrier of 0.45 eV. The binding at F and F+ oxygen vacancy defects is weaker than on the terrace. Small Ca clusters on the s...

Monte Carlo simulations were used to investigate the conformational and electrical properties of isolated weak polyelectrolytes in the presence of an oppositely charged particle. Titrations curves were calculated to get an insight into the role of pH on the degree of ionization and conformation of isolated chains. The effect of ionic concentration and polyelectrolyte length on the titration cur...

A systematic and detailed analysis of adsorption and diffusion properties of xylene isomers over Beta zeolites with different mesoporosity was conducted. Adsorption isotherms of xylene isomers over microporous and mesoporous Beta zeolites through gravimetric methods were applied to investigate the impact of mesopores inside Beta zeolites on the adsorption properties of xylene isomers in the pre...

We present experimentally measured adsorption isotherms of CO2, H2, and N2 on a phenol-formaldehyde resin-based activated carbon, which had been previously synthesized for the separation of CO2 in a precombustion capture process. The single component adsorption isotherms were measured in a magnetic suspension balance at three different temperatures (298, 318, and 338 K) and over a large range o...

Statherin is a salivary protein that inhibits the nucleation and growth of hydroxyapatite crystals in the supersaturated environment of the oral cavity. The thermodynamics of adsorption of statherin onto hydroxyapatite crystals have been characterized here by isothermal titration calorimetry and equilibrium adsorption isotherm analysis. At 25 degrees C, statherin adsorption is characterized by ...

Microporous and mesoporous zincosilicates (e.g., CIT-6, VPI-8, Zn-MFI, and Zn-MCM-41) synthesized in the presence of alkali cations contain two broad types of Zn sites: one that is a dication analog of the monocation ion-exchangeable Al-site in aluminosilicates, while the other resembles isolated Zn sites on amorphous silica. The ratio of these sites varies, depending on the synthesis condition...