This paper considers the degradation of alumina and zirconia toughened alumina vs. alumina for hip implants. The materials are as assumed to be load bearing surfaces subjected to shocks in wet conditions. The load is a peak of force; 9 kN was applied over 15 ms at 2 Hz for 800,000 cycles. The volumetric wear and roughness are lower for ZTA than for alumina. The long ZTA ageing did not seem to h...

The series of mono-metallic and bi-metallic catalysts have been prepared by impregnatingwith solutions containing compound of H2PtC15,NbC15 and lml HC1 (0.1 mol). The activityand selectivity of the catalysts have been determined under conditions at 450-500°C, 15-30atm. Molar ratio H2/C7H16=5 and VVH=1.5/h for converting n-heptane. Under theseexperimental conditions it has been established that ...

Catalyitic reforming is one of the refinery processes in catalyst conversion that results to anincreases in octane number of naphtan which leads to production of gasoline with higher octanenumber. Hydrocarbons with high octan number that are produced in reforming process are as;aromatics, paraffins, isomers and etc.Not only Aromatics are used as fuel for motors but they are also useful in petro...

Alumina nanomaterials were synthesized via a solution combustion technique using tris-(acetylacetonato) aluminum(III) complex (1) and tris-(2-formylphenolate) aluminum(III) complex (2) at 600, and 1000 °C for 3h. The obtained data showed that the procedure without using fuel resulted in a better phase and morphology. To investigate the phase formation, powder X-ray diffraction technique was use...

Anodic porous alumina has been widely investigated and used as a nanostructure template in various nanoapplications. The porous structure consists of numerous hexagonal cells perpendicular to the aluminum substrate and each cell has several tens or hundreds of nanoscale pores at its center. Because the nanomorphology of anodic porous alumina is limited by the electrolyte during anodizing, the d...

Experimental researches on adsorptive capacity of activated alumina, silica sand and anthracite coal for phosphorus were conducted. Results showed that performances of three filter media were all in line with Langmuir isotherm, and activated alumina adsorptive performance was much better than silica sand and anthracite coal for phosphorus removal. The adsorptive capacity of activated alumina, s...

Mono-phase bio-ceramics (alumina and zirconia) are widely used as femoral heads in total hip replacements (THR) as an alternative to metal devices. Unfortunately, the orthopaedic community reports significant in-vivo failures. Material scientists are already familiar with composites like alumina zirconia. Since both are biocompatible, this could prove to be a new approach to implants. This pape...

Quantum two-level systems (TLSs) are present in the materials of qubits and considered defects because they limit qubit coherence. For superconducting qubits, quintessential Josephson junction barrier is made amorphous alumina, which hosts TLSs. However, TLSs not understood generally -- either structurally or atomic composition. In this study, we greatly extend quantitative data available on by...

Simple nanoporous alumina matrix modification procedure, in which the electrically highly insulating alumina barrier layer at the bottom of the pores is replaced with the conductive layer of the gold beds, was described. This modification makes possible the direct electron exchange between the underlying aluminum support and the redox species encapsulated in the alumina pores, thus, providing t...

INTRODUCTION Incorporating a feldspar chemical bond between alumina filler particles is expected to increase the wear-resistant and flexural strength properties. AIMS AND OBJECTIVES An investigation was carried out to evaluate the influence of the feldspar chemical bonding between alumina filler particles on wear and flexural strength of experimental alumina/feldspar dental composites. It was...