In heterogeneous catalysis transition metal-containing zeolites, in particular copperexchanged zeolites, have been studied experimentally [1, 2] as well as theoretically. Zeolites have large surface areas and different active sites (Brønsted acid sites and transition metal centers) which play a significant role in catalysis. In order to study the catalytic oxidation of benzene to phenol using d...

We have studied possible adsorption geometries of neutral NaCl clusters on the disordered surface of a large silicon model tip used in non-contact atomic force microscopy. The minima hopping method was used to determine low energy model tip configurations as well as ground state geometries of isolated NaCl clusters. The combined system was treated with density functional theory. Alkali halides ...

We study the adsorption of homogeneous or heterogeneous polymers onto heterogeneous planar surfaces with exponentially decaying site-site correlations, using a variational reference system approach. As a main result, we derive simple equations for the adsorption-desorption transition line. We show that it is preferable to have a small amount of strongly adsorbing sites or monomers rather than a...

BACKGROUND The application of surface complexation models (SCMs) to natural sediments and soils is hindered by a lack of consistent models and data for large suites of metals and minerals of interest. Furthermore, the surface complexation approach has mostly been developed and tested for single solid systems. Few studies have extended the SCM approach to systems containing multiple solids. RE...

X-ray standing waves have been employed to study the microscopic mechanism of surfactant mediated epitaxy of Ge on Si~111!. After deposition of 0.5 BL Ge on the Ga:Si~111!-6.336.3 surface we find Ga floating on the surface in a Ga-Ge bilayer with Ga in a substitutional adsorption site. Deposition of 0.5 BL Ge on the Ga:Si~111!-A33A3 surface leads to a change of the Ga adsorption site from T4 to...

A new series of Ba-Co-O perovskite-type oxygen carriers has been successfully synthesized by the microwave-assisted sol-gel method and further applied for producing an O2/CO2 mixture gas. The oxygen adsorption/desorption performance of synthesized samples was studied in a fixed-bed reactor system. Effects of A/B-site substitution on the oxygen desorption performance of Ba-Co-O–based perovskites...

In this study, the adsorption of 4-hydroxy phenyl-azobenzene on the surface of (4, 0) zigzag open-end boron nitride nanotube (BNNT) has been investigated by quantum calculations. In order to find the preferred adsorption site, different positions and orientations were considered. The impacts of donor-acceptor electron delocalization on the structural and electronic properties and reactivity of ...

The structure and electronic properties of 1-ML Au supported on TiO2~110! have been theoretically investigated using the full potential linearized augmented plane-wave method. Based on total-energy and atomicforce calculations, the preferential adsorption site for the Au adatom is predicted to be the atop site above the fivefold surface Ti atom, with a bond length of dAu-Ti52.66 Å and an adsorp...

Temperature and magnetism bi-responsive molecularly imprinted polymers (TMMIPs) based on Fe3O4-encapsulating carbon nanospheres were prepared by free radical polymerization, and applied to selective adsorption and controlled release of 5-fluorouracil (5-FU) from an aqueous solution. Characterization results show that the as-synthesized TMMIPs have an average diameter of about 150 nm with a typi...

Surface-supported molecular self-assembly with the goal to produce highly ordered, functional supramolecular nanostructures are often realized using nanopatterned surfaces, which exhibit long range - ideally periodic - modulations of the molecule adsorption properties. To elucidate the physical origins of the site-specific adsorption properties of such a nanopatterned substrate, we investigated...