A density functional theory (DFT) constructed from the modified fundamental-measure theory and the modified Benedict-Webb-Rubin equation of state is presented. The Helmholtz free energy functional due to attractive interaction is expressed as a functional of attractive weighted-density in which the weight function is a mean-field-like type. An obvious advantage of the present theory is that it ...

the used activated carbon was derived from pine-cone and was used for the removal of acid black 1(ab1) and acid blue 113(ab113) dyes. a batch sorption study was carried out in order to obtain optimum isotherm model. the study showed the best fit of the adsorption isotherm data was obtained using the langmuir model for both dyes. the monolayer maximum saturation capacities of ab1 and ab113 dyes ...

Adsorption is a common unit operation in separation and purification of biotechnological products where chromatography steps can make up more than half the amount of the total purification costs [1]. The molecular mechanisms of adsorption are still not understood in detail. Further understanding of interactions between adsorbent surfaces and adsorptives could help to facilitate process design i...

The adsorption of a collagen fragment on both a hydrophobic, hydrogen-terminated and a hydrophilic, natively oxidised Si surface is investigated using all-atom molecular dynamics. While favourable direct protein-surface interactions via localised contact points characterise adhesion to the hydrophilic surface, evenly spread surface/molecule contacts and stabilisation of the helical structure oc...

On fabrication by contact printing, a nanostructured self-assembled monolayer (SAM) of alkanethiol contains a substantial fraction of unbound molecules that are either inverted among other upright molecules or piled on top of the SAM. The molecular dynamics simulation in the present study demonstrates that thermal annealing cures these defects for a SAM island of octadecanethiol. The SAM island...

We followed the collective atomic-scale motion of Na atoms on a vicinal Cu(115) surface within a time scale of pico- to nanoseconds using helium spin echo spectroscopy. The well-defined stepped structure of Cu(115) allows us to study the effect that atomic steps have on the adsorption properties, the rate for motion parallel and perpendicular to the step edge, and the interaction between the Na...

Binding configurations, interface electronic structures, and magnetic properties of 3d transition-metal phthalocyanine (MPc, where M = Mn, Fe, Co, Ni, Cu or Zn) molecular systems on a Au(111) substrate are systematically investigated with first-principles density functional theory calculations using the Perdew-Wang (PW91) exchange-correlation functional. We also calculate the corresponding prop...

This report examines the assembly of chalcogenide organic molecules on various surfaces, focusing on cases when chemisorption is accompanied by carbon-chalcogen atom-bond scission. In the case of alkane and benzyl chalcogenides, this induces formation of a chalcogenized interface layer. This process can occur during the initial stages of adsorption and then, after passivation of the surface, mo...

In superconformal filling of copper-chip interconnects, organic additives are used to fill high-aspect-ratio trenches or vias from the bottom up. In this study we report on the development of intermolecular potentials and use molecular dynamics simulations to provide insight into the molecular function of an organic additive (3-mercaptopropanesulfonic acid or MPSA) important in superconformal e...

Chemical properties of epitaxially grown bimetallic layers may deviate substantially from the behavior of their constituents. Strain in conjunction with electronic effects due to the nearby interface represent the dominant contribution to this modification. One of the simplest surface processes to characterize reactivity of these substrates is the dissociative adsorption of an incoming homo-nuc...