1. Introduction Mesoporous materials with ordered arrays of uniform nanochannels of a controllable size have wide-ranging applications, one of which is membrane separation. In order to be used as a membrane for size-exclusive separation of molecules, it is necessary to synthesize a defect-free structure with continuous nanoporosity. Mesoporous silica and porous anodic alumina have been extensiv...

Typically, alumina nanowires (NWs) are synthesized via physical evaporation, templated anodized aluminum oxide (AAO), or the vapor-liquid-solid (VLS) process [1,2,3]. All of these techniques have been shown to demonstrate successful growth of alumina NWs; however, in the cases where a facile method resulting in vertically aligned NWs is desired, many of these methods are difficult to integrate ...

Between 1990 and 1992, we implanted 71 hybrid alumina-on-alumina hip arthroplasties in 62 consecutive patients under the age of 55 years, with a mean age of 46 years at surgery. There were 56 primary and 15 secondary procedures. The prostheses involved a cemented titanium alloy stem, a 32 mm alumina head, and a press-fit metal-backed socket with an alumina insert. Three patients (four hips) die...

This study evaluated the effect of alumina-blasting and three commercial adhesive primers on the shear bond strength of a dual-cured resin luting agent to zirconia ceramics. Two different-sized zirconia ceramic specimens were treated with or without alumina-blasting and then treated with one of three adhesive primers. Subsequently, specimens were cemented together with Linkmax HV (GC). Half of ...

Infrared spectroscopy is used to follow the chemical changes, as a function of temperature, after sequentially adsorbing trimethylaluminum (TMA) and methanol on hydroxylated alumina. Deuterium-labeled methanol is used to distinguish between the chemistry of methyl and methoxy species. To differentiate between methanol adsorbed on TMA-derived sites and on alumina, the adsorption of methanol is s...

OBJECTIVE To describe bauxite mining and alumina refining processes and to outline the relevant physical, chemical, biological, ergonomic, and psychosocial health risks. METHODS Review article. RESULTS The most important risks relate to noise, ergonomics, trauma, and caustic soda splashes of the skin/eyes. Other risks of note relate to fatigue, heat, and solar ultraviolet and for some opera...

Introduction Nanocrystalline gamma-phase (γ) alumina is among many polytypes of alumina that find extensive applications as a catalyst and catalytic supports. The most useful properties these aluminas provide as catalyst supports are high surface area and welldefined porosity. These properties result primarily from the nano-scale crystalline character of the alumina. The problem is that both th...

This article examines the effect of interfacial load transfer on the stress distribution in carbon nanotube/polymer composites through a stress analysis of the nanotube/matrix system. Both isostrain and isostress loading conditions are investigated. The nanotube is modeled by the molecular structural mechanics method at the atomistic level. The matrix is modeled by the finite element method, an...

A crackand pinhole-free composite membrane consisting of an a-alumina support and a modified y-alumina top layer which is thermally stable up to 1100°C was prepared by the sol-gel method. The supported thermally stable top layer was made by dipcoating the support with a boehmite sol doped with lanthanum nitrate. The temperature effects on the microstructure of the (supported and unsupported) La...

Textural evolution (porosity reduction, pore and crystallite growth) in titania-alumina composite membranes has been studied using thermal analysis, X-ray diffraction, field emission scanning electron microscopy and N, physisorption techniques. The presence of alumina in the membranes improved the thermal stability of the porous texture by retarding the anatase-to-rutile phase transformation a...