The thermal-diffusion and diffusion-thermo effects on heat and mass transfer by transient free convection flow of over an impulsively started isothermal vertical plate embedded in a saturated porous medium were numerically investigated, considering a homogeneous chemical reaction of first order. The transient, nonlinear and coupled governing equations are solved using an implicit finite-differe...

The thermo-optic effect of Si nanocrystals in silicon-rich silicon oxide (SRSO) thin films at 1530 nm is investigated. SRSO thin films, which consist of nanocrystal Si (nc-Si) embedded inside the SiO2 matrix, were prepared by electron-cyclotron-resonance plasma-enhanced chemical vapor deposition of SiH4 and O2 followed by a 30 min anneal at 1150 °C. The refractive indices of all SRSO films incr...

The worldwide production of polymeric foam materials is growing due to their advantageous properties light weight, high thermal insulation, good strength, resistance and rigidity. Society creates ever increasing amounts poly-urethane (PU) waste. A major part this waste can be recycled or recovered in order put into further use. PU industry committed assist play its the process. recycling recove...

The article presents the influence of thermo-chemical treatment Al2O3 layers on their tribological properties. were produced EN AW-5251 aluminium alloy by means direct current anodizing in a three-component electrolyte. For sake comparison, some samples thermochemically treated three liquids (sodium sulphate solution, sodium dichromate distilled water). parameters production and selected basis ...

We demonstrate that isophthalic acid-ended telechelic poly(1,5-cyclooctadiene)s (APCODs) form thermo-reversible gels in non-polar solvent with a unique molecular mechanism for their thermo-reversibility. Like other associative telechelic polymers, A-PCODs form “flower-like” micelles at low concentration and form gels through bridging at higher concentration which exhibit linear viscoelasticity....

Thermo-diffusion effect on free convection heat and mass transfer from a vertical surface embedded in a liquid saturated thermally stratified non Darcy porous medium has been analyzed using a local non-similar procedure. The wall temperature and concentration are constant and the medium is linearly stratified in the vertical direction with respect to the thermal conditions. The fluid flow, temp...

In the present work we aim to clarify the role of the microstructure and the crystalline distribution from the thermo-oxidation of solid isotactic PP (iPP) and ethylene-propylene (EP) copolymers. The effects of the content and quality of the isotacticity interruptions, together with the associated average isotactic length, on the induction time (ti) as well as on the activation energy (Eact) of...

This paper explores a possible design for a CMOS compatible, athermal, optical waveguide. The design explored is a slot waveguide with light guided in the low index material. A design paradigm is proposed which shows the relationship between cross-sectional parameters and their impact on both the effective index of refraction and the thermo-optic coefficient of the device. Two materials choices...