The influence of composition and purity of titanium on the mechanical properties and the transformation temperatures of Ni-Ti alloy dental castings was investigated by tensile testing and differential scanning calorimetry (DSC). The compositions of the ingots were 49.0-49.2 at% of titanium content. Three grades of titanium of relatively high purity were used as starting materials. The result sh...

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Introduction: Grains of composition with Fe, Ni and Cl are reported as relicts of awaruite (in mafic minerals of olivine and serpentine from the interior of the Earth) [1] or meteoritic mixture found originally at the fusion crust melted in atmosphere [2, 3, 4]. Recently author (YM) discusses that carbon contents of these phases are significant to discuss the sources of Fe, Ni and Cl [2, 3, 4, ...

We have investigated the role of aluminum oxide films as barriers to thermal oxidation of Co, Ni, Fe, Ni Fe , Mn, Ta, Cu 80 20 and Cr in air. The oxidation of the film is monitored by measuring the electrical resistance following a brief anneal in air. We find that 0.3 and 1 nm Al protect the underlying metal film against thermal oxidation in air at temperatures of a few hundred degrees above t...

Context. The chemical analysis of secondary stars of low mass X-ray binaries provides an opportunity to study the formation processes of compact objects, either black holes or neutron stars. Aims. Following the discovery of overabundances of α-elements in the Keck I/HIRES spectrum of the secondary star of Nova Scorpii 1994 (Israelian et al. 1999), we obtained VLT/UVES high-resolution spectrosco...

Uptake hydrogenase is an enzyme that is beneficial for nitrogen fixation in bacteria. Recent studies have shown that Frankia sp. has two sets of uptake hydrogenase genes, organized in synton 1 and synton 2. In the present study, phylogenetic analysis of the structural subunits of hydrogenase syntons 1 and 2 showed a distinct clustering pattern between the proteins of Frankia strains that were i...

the major aim of the present study was to investigate element (fe, ni, pb, v, zn) concentrations in sediment and different tissues of phragmities australis and typha latifolia in hor al-azim wetland southwest iran. sampling of sediments and aquatic plants was carried out during spring and summer 2014. results showed that the mean  concentrations of elements in phragmities australis  in root and...

Introduction: The evidence for the presence of short-lived Fe (decaying into Ni, with the half life of 1.5 Ma) in the early system has recently received considerable attention, both experimentally and theoretically. Evidence for Ni excesses in eucrites, without correlation to Fe/Ni has been obtained by Shukolyukov and Lugmair [1, 2]. Recently, based on ion microprobe studies of phases with very...

in this study, multi wall carbon nanotubes (mwcnts) were synthesized by chemical vapor deposition (cvd) method using two different catalysts (fe nanoparticles) and (ni nanoparticles) with  two different substrates: quartz and alumina. acetylene gas was used as a carbon source and argon as a carrier gas at different temperatures and different times to study the effects of these parameters on cnt...

Sir, It was good to see Dr Ni Brolchain's interesting study of children with special educational needs (February Journal, p.56). They form a small but important subgroup of a practice child population. I suspect these children and their families may well have higher consultation rates than a control group without special educational needs. I trained for general practice (including nine months i...