Ceramic Ultrafiltration membranes are considered as an alternative for the treatment of both stable water-in-oil and oil-in-water emulsions proved to be more effective in comparison with other conventional techniques. In this study, symmetric macro-porous ceramic membranes are prepared through dry pressing of α-alumina powder and the addition of various binders including Poly (vinyl alcohol). T...

Temperature- and humidity-sensing properties were evaluated of NixMg1-x spinel ferrites (0 ≤ x 1) synthesized by a sol-gel combustion method using citric acid as fuel nitrate ions oxidizing agents. After the exothermic reaction, amorphous powders calcined at 700 °C followed characterization with XRD, FTIR, XPS, EDS Raman spectroscopy FESEM microscopy. Synthesized tested humidity- temperature-se...

Simultaneous application of colloidal processing and liquidforming additives to alumina resulted in a sintered density of >99% in 1 h at a temperature as low as 1070°C for a commercial high-purity alumina powder at a total dopant level of 2 mol%. The additives were 0.9% CuO + 0.9% TiOz + 0.1% B 2 0 3 + 0.1% MgO. At higher temperatures or after prolonged sintering, the doped alumina ceramic deve...

A comparison has been made of the infrared spectra of alumina with molybdenum oxide alumina in both the oxidized and reduced forms. In the case of molybdena-alumina prepared via adsorption of gaseous MoOp(OH)t, the spectra show that a practically complete monolayer of Mo6+ oxide covers the alumina. After reduction with hydrogen the hydroxyls of the carrier appear. From the reversibility of redu...

Porous alumina film on aluminum with gel-like pore wall was prepared by a two-step anodization of aluminum, and the corresponding gel-like porous film was etched in diluted NaOH solution to produce alumina nanowires in the form of densely packed alignment. The resultant alumina nanowires were reacted with NH(3) and evaporated aluminum at an elevated temperature to be converted into densely pack...

The growth of ordered nanorods of mesoporous SBA-15 inside a porous alumina membrane has been achieved for the first time by a simple sol-gel method. The obtained SBA-15 nanorods themselves have ordered hexagonal mesochannels with a size of about 6 nm and have been arranged to form hexagonal arrays by the limitation of pores of the alumina membrane. The synthesized alumina membrane with mesopor...

In this thesis multi-component mass transport in thin supported amorphous silica membranes is discussed. These membranes are micro-porous, with pore diameters smaller than 4Å and show high fluxes for small molecules (such as hydrogen) combined with high selectivities for these molecules with respect to larger ones. The chemical and thermal stability of silica membranes are favourable compared t...

OBJECTIVE The study aimed to evaluate effects of air abrasion with alumina or glass beads on bond strengths of resin cements to CAD/CAM composite materials. MATERIAL AND METHODS CAD/CAM composite block materials [Cerasmart (CS) and Block HC (BHC)] were pretreated as follows: (a) no treatment (None), (b) application of a ceramic primer (CP), (c) alumina-blasting at 0.2 MPa (AB), (d) AB followe...