BACKGROUND Ceramic-on-ceramic couplings are attractive alternative bearing surfaces that have been reported to eliminate or reduce problems related to polyethylene wear debris. Disappointing experiences with alumina ceramic bearings in the past have led to many improvements in the manufacture and design of ceramic implants. The purpose of the present study was to report the results of contempor...

Atmospheric plasma spraying (APS) is a well established process for preparing ceramic coatings. In this process, powder particles injected into the plasma jet are heated and accelerated simultaneously in the plasma stream and are deposited in molten or semi-molten droplets conditions onto a prepared substrate. During droplet impingement, these molten droplets rapidly solidify to form single spl...

Alumina-rich iron ore is a widely existed polymetallic deposit in the nature, and it has a high comprehensive utilization value. Because the alumina and iron contents of alumina-rich iron ore vary from each other, there are many different measures and processes to recover iron and alumina from the various kinds of alumina-rich iron ore. In the blast furnace (BF) ironmaking process, the alumina ...

BACKGROUND While most reports of component fracture following alumina-on-alumina total hip arthroplasty have involved the acetabular liner, few have involved fracture of the alumina femoral head. In the present multicenter study, we investigated ceramic head fractures in a cohort of patients who underwent third-generation alumina-on-alumina total hip arthroplasty. METHODS We performed a retro...

Zeolite NaA-type membranes hydrothermally synthesized on porous alumina tubes, for dehydration process, were characterized by grazing incidence 2 theta scan X-ray diffraction analysis (GIXRD). The fine structure of the membrane was studied fractionally for surface layer and for materials embedded in the porous alumina tube. The thickness of the surface layer on the porous alumina tube in the me...

Vapor expansion from Al target irradiated by a continuous wave laser into a supersonic external air flow is investigated in kinetic simulations performed for values of pressure in the external flow ranging from 50 Pa to 10000 Pa. The direct simulation Monte Carlo method enhanced with a simplified description of Al vapor burning in air is used in the simulations. The results of the simulations r...

Novel α-alumina crystalline nanosheets are used for the preparation of alumina-carbon composites, in which the latter component is phenolic resin-based ordered mesoporous carbon. A unique feature of these composites is perpendicular orientation of ordered mesopores of the carbon to the (001) facets of nonporous α-alumina nanosheets accompanied by significant enlargement of these mesopores in co...

In order to understand the beneficial effect of Pt on the adherence of thermally grown alumina scales, sessile drop experiments were performed to study the wetting of poly-crystalline alumina by nickel-aluminum alloys with or without platinum addition where the amount of Pt ranged from 2.4 to 10 at.%. Subsequent interfacial structure was evaluated using atomic force microscopy. Platinum additio...

The effects of (+ )-catechin adsorption to the alumina surface were studied by -potential and surface free energy determination. The presence of catechin causes essential changes in the alumina -potential, which at the concentration slightly higher than 10 M reverses from the positive into negative one. At constant concentration of catechin (10 M), the effect on -potential of alumina as a funct...