Fixed bed biofilm reactors with granular activated carbon (GAC) or glass beads as support media were used to evaluate the influence of short-term (12h) and long-term (23 days) increases of influent dissolved oxygen (DO) concentrations on biological perchlorate removal. The goal was to evaluate the extent by which chemisorption of oxygen to GAC can enhance the stability of biological perchlorate...

Density functional theory has been used to study the interaction of molecular and atomic hydrogen with ~5,5! and ~6,6! single-wall carbon nanotubes. Static calculations allowing for different degrees of structural relaxation are performed, in addition to dynamical simulations. Molecular physisorption inside and outside the nanotube walls is predicted to be the most stable state of those systems...

Six-dimensional quantum dynamics calculations are now possible for fully activated dissociative chemisorption of H 2. We present results for the reaction of (y ­ 0, j ­ 0) H 2 on Cu(100). The potential energy surface was taken from density functional theory (DFT), using the generalized gradient approximation. Comparison to experiment suggests that, on average, the DFT method overestimates the b...

Phase diagram showing the appearance of ferromagnetism on a non-magnetic metal surface as result chemisorption.

A series of zwitterionic hybrid membranes were prepared via the ring opening of 1,3-propanesultone with the amine groups in the chains of TMSPEDA and a subsequent sol-gel process. Their kinetic models for strontium removal were investigated using three two-parameter kinetic equations (i.e., Lagergren pseudo-first order, pseudo-second order, and Elovich models). Adsorption mechanism was evaluate...

Electronic friction and the ensuing nonadiabatic energy loss play an important role in chemical reaction dynamics at metal surfaces. Using molecular dynamics with electronic friction evaluated on the fly from density functional theory, we find strong mode dependence and a dominance of nonadiabatic energy loss along the bond stretch coordinate for scattering and dissociative chemisorption of H_{...

We perform a detailed study of the static and dynamical properties of molecular oxygen adsorption on Ag(110) based on semi-local density functional theory (DFT) calculations and compare the results to experimental studies. For the classical dynamics calculations we use two complementary approaches, ab initio molecular dynamics and dynamics on a precalculated potential energy surface. In contras...

Palladium supported Al2O3 and SiO2 catalysts have been synthesized and evaluated for carbon monoxide oxidation in the presence of ozone. The factors affecting the CO oxidation such as Pd loading (wt%), contact time, reaction temperature and O3/CO molar ratio have been studied. The extent of ozone decomposition on Pd catalysts is proportional to the CO oxidation activity. High reaction temperatu...