The forces between a silica probe and an n-type TiO2 single-crystal electrode were measured using an atomic force microscope in an aqueous electrolyte solution. These interactions were a strong function of the solution pH, the presence of specifically adsorbed anions, and the TiO2 electrode potential. For a series of pH values, a strong electrostatic repulsion was seen at high pH and decreased ...

alteration of ophiolitic ultramafic rocks, formation of listwaenite and associated mineralization are interesting phenomena of metallogeny of khoy ophiolite. it seems that the hydrothermal circulations responsible for mercury mineralization were derived from geothermal systems caused by intermediate to acidic magmatism in neogene-pleistocene time. reactivation of brecciated serpentinite with hy...

The first part of the review contrasts the main drawbacks of silica-based packings such as their relative thermal and chemical instability with excellent stability of metal oxides. The paper concerns mainly ZrO2, TiO2 and Al2O3. Methods of preparation of spherical particles for HPLC are described. Surface chemistry of the oxides is, however, very different from that of silica. Ability of the ox...

mixed-addenda vanadium substituted polyoxometalate supported on anatase tio2 crushed nano leaf was synthesized by an unusual reaction with titanium tetraisopropoxide at 100 ºc via sol–gel method under oil-bath condition. the materials characterized by xrd, tem,  ir and uv–vis  techniques.  in  the  present  work,  efficient  oxidative  of  thiols  with  polyoxometalate-tio2/hydrogen  peroxide  ...

The selective oxidation of methanol to formaldehyde occurring on titania-supported vanadate species has been analyzed theoretically with the aim of understanding why the activity of VOx/TiO2 is ∼103 faster than that of VOx/SiO2. The active site was represented by a [(O)3VdO] group located at the corner of a cubic TiOx cluster, a model similar to that used successfully to describe the oxidation ...

The Turkevich synthesis method of Au nanoparticles (AuNPs) was adopted for direct fabrication of SiO2@Au and TiO2@Au core-shell nanostructures. In this method, chloroauric acid was reduced with trisodium citrate in the presence of amine-functionalized silica or titania submicroparticles. Core-shells obtained in this way were compared to structures fabricated by mixing of Turkevich AuNPs with am...