In this study, a precursor for carbon nanofibers (CNF) was fabricated via electrospinning and carbonized through a thermal process. Before carbonization, oxidative stabilization should be applied, and the oxidation mechanism also plays an important role during carbonization. Thus, the understanding of the oxidation mechanism is an essential part of the production of CNF. The oxidation process o...

The objective of this study was to mimic the microstructure of MCrAlY coatings sprayed using HVOF (High Velocity Oxy-Fuel) processes by using an Air Plasma Spray (APS) process in order to improve oxidation and spallation life of MCrAlY APS coatings. Figure 1 shows the typical microstructures obtained when spraying bond coats using the (a) HVOF process, and (b) the APS process. The microstructur...

Porous silicon (PSi) is a nanostructured material possessing a huge surface area per unit volume. In consequence, the adsorption and diffusion of oxygen in PSi are particularly important phenomena and frequently cause significant changes in its properties. In this paper, we study the thermal oxidation of p+-type free-standing PSi fabricated by anodic electrochemical etching. These free-standing...

The effect of nanostructure on the thermal oxidation of atomized iron has been investigated. Above 500 o C atomized iron is oxidized in the presence of air. However, when iron is compacted with multiwalled carbon nanotubes (MWCNT) this oxidation is shifted by more than 100 o C. Iron is protected by the nanostructure environment A large number of compositions of atomic ratios of iron and MWCNT h...

The effects of UV (193 nm) laser irradiation of ant imony in the atmosphere on the kinetics of oxidation and on the oxide stoichiometry have been studied using a quartz microbalance and X-ray photoelectron spectroscopy. An absolute calibration of the quartz microbalance enables us to measure quantitatively the kinetics of the oxygen uptake on a thin film; while XPS results indicate the evolutio...

Marine and inland pollution by non-degradable plastic bags and other plastic articles is a topic of great concern. Natural degradation processes based on oxidation of plastic pollutants could possibly contribute to limit the extent of pollution. Thermal degradation of polyolefins in the absence of light by non-polluting pro-oxidants has not been presented before. In this study, we show that two...

one distinct concentration of copper ions was embedded into the silica matrix to xerogel form using copper source cu(no3)2∙3h2o. the xerogel samples were prepared with using hydrolysis and condensation reactions of tetraethyl ortho-silicate (teos) by the sol-gel method. in this investigation, new molar ratio of h2o/teos was determined to be 11.7. also, the necessary amount of tri-hydrated coppe...

PURPOSE Previous studies have shown that alpha-crystallin, a major lens protein, acts as a chaperone preventing the thermal denaturation of other lens crystallins. However, there has not been an examination of the alpha-crystallin chaperone ability with respect to the types of insult thought to cause human cataract. Therefore, an examination of the chaperone potential of alpha-crystallin under ...

The oxidation of acid-soluble calf skin collagen type I caused by metal-dependent free radical generating systems, Fe(II)/H2O2 and Cu(II)/H2O2, was found to bring down in a specific, discrete way the collagen thermal stability, as determined by microcalorimetry and scanning densitometry. Initial oxidation results in splitting of the collagen denaturational transition into two components. Along ...