In the present investigation surface modification of silica nanoparticles by alumina was carried out by sol-gel process. Fourier transform infrared (FTIR) and X-ray fluorescence (XRF) confirmed the synthesis of silica and the surface modification as alumina is anchored to silica surface. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) investigation...

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...

We study the effect of global and local dielectric variations on the polarization conversion rps response of ordered nickel nanowires embedded in an alumina matrix. When considering local changes, we observe a non-monotonous behavior of the rps, its intensity unusually modified far beyond to what it is expected for a monotonous change of the whole refractive index of the embedding medium. This ...

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 ...

We present a method to make phantoms of coronary arteries for intravascular optical coherence tomography (IV-OCT). The phantoms provide a calibrated OCT response similar to the layered structure of arteries. The optical properties of each layer are achieved with specific concentrations of alumina and carbon black in a silicone matrix. This composition insures high durability and also approximat...

The present work was focused on obtaining biocide coatings constituted by a glassy soda-lime matrix containing silver or copper nanoparticles on ceramic (alumina and zirconia based) substrates. Both glassy coatings showed a high biocide activity against Gram-, Gram+ bacteria and yeast, reducing cell numbers more than three logarithms. Silver nanoparticles had a significantly higher biocide acti...

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...