This report presents a simplified surface reaction mechanism for the Chemical Vapor Deposition (CVD) of diamond thin films. The mechanism also accounts for formation of point defects in the diamond lattice, an alternate, undesirable reaction pathway. Both methyl radicals and atomic carbon are considered as growth precursors. While not rigorous in all its mechanistic details, the mechanism is us...

The chemical crosslinking of modified nucleic acids via the Diels-Alder reaction is reported. For this purpose, 1,3-butadiene derived building blocks were incorporated into complementary oligodeoxynucleotides. Treatment of the obtained duplex with difunctional dienophiles results in the clean crosslinking of the two strands. Non-crosslinked adducts arising from a single Diels-Alder reaction of ...

The paper presents an approach of the Bond Graph modelling applied to thermo-chemical processes. The proposed work focused on combustion process kinetics with respect to reactant and reactor input data. The model provides information on the time variation of the heat of reaction, reaction products concentration, and reactants concentration / accumulation, based on global mass and energy balance...

We demonstrate the use of intense, quasi-half-cycle THz pulses, with an associated electric field component comparable to intramolecular electric fields, to direct the reaction coordinate of a chemical reaction by stimulating the nuclear motions of the reactants. Using a strong electric field from a THz pulse generated via coherent transition radiation from an ultrashort electron bunch, we pres...

Droplets that are driven away from thermal equilibrium by chemical reactions can exhibit rich dynamic behaviors. When droplet material turns over by chemical reactions a spherical droplet can become unstable and divide spontaneously. We study the effects of hydrodynamic flows in this droplet division. We solve the reaction diffusion equations of a phase separating system coupled to hydrodynamic...

The effects of thermo-diffusion (Soret effect) and diffuso-thermal gradients (Dufour effect) on the unsteady incompressible magneto-hydrodynamic (MHD) free convection flow with mass transfer past a semi-infinite vertical plate in a Darcian porous medium in the presence of significant thermal radiation, first order homogenous chemical reaction and viscous heating are analyzed. The governing diff...

Experimental studies of gas-phase nanoparticle coating by photoinduced chemical vapor deposition (photoCVD) have shown that silica coatings can be produced with controllable thicknesses on different nanoparticle cores for a variety of applications. This study presents a chemical reaction sequence for the photo-CVD process to describe the production of silica coatings from the decomposition of t...

In applications to several simple reaction systems we have explored a “direct simulation” method for predicting and understanding the behavior of gas phase chemical reaction systems. This Monte Carlo method, originated by Bird, has been found remarkably successful in treating a number of difficult problems in rarefied dynamics. Extension to chemical reactions offers a powerful tool for treating...

using c2h2, 112 and as gases at 550'c, carbon nanotubes were fabricated on the surfaces of twosubstrates coated by nano thin layers of metal catalysts by dc magnetron sputtering. aystamless steel andfe/cteal, by thermal chemical vapor deposition (tcvd) the surface properties of the substrates wereparticularly investigated, and the effect of treatment of the substrates on the cnt's growth is cri...

The Diels–Alder reaction is a powerful tool in organic synthesis and in the chemical industry. Recently an increased attention has been focused on the development of green methods for the purpose of improving rate and selectivity of this reaction. In recent years, ionic liquids (ILs) have gained a lot of attention as green solvents in organic synthesis and other chemical processes. This is main...