ethyl benzene used increasingly each year is the raw material of producing styrene monomer. this substanceis produced from benzene alkylation with ethylene or ethanol, depending on the availability and cost of rawmaterials. in this study benzene alkylation in the presence of ethanol in a catalytic fixed bed reactor inthree states of isotherm, adiabatic and non-isotherm-non-adiabatic is mathemat...

in the present work, attempts have been made to find appropriate coating by testing different compounds. results showed that the optimum enamel is a compound with 1 wt.% cobalt oxide, 3 wt.% chromium oxide (in addition to hundred percent) with the firing temperature of 840 ˚c. constants of vft equation were determined by examination of melting behavior of the optimum enamel and measurement of t...

Mn doped GaAs thin films were grown using molecular beam epitaxy at high and low substrate temperatures. The elemental concentration depth profiles in the thin films were determined by using Auger electron spectroscopy combined with ion etching. The Mn concentration is higher near the surface and then decreases with depth for films grown at high substrate temperatures. The Mn concentration prof...

We present a theoretical study of spatially modulated phases in self-assembled monolayers of mixed surfactants. We propose two models which are appropriate, respectively, for monolayers at a fluid-fluid interface and monolayers on a solid substrate. We show that in both cases, the molecular shape asymmetry, coupled with the local composition variation, can lead to spontaneous formation of perio...

To control deposition profile of carbon films in trenches, we have studied substrate temperature and aspect ratio dependence of deposition rate of carbon films, deposited by CVD plasma of toluene diluted H2, in trenches. The deposition rates increases with decreasing the aspect ratio, because the incident radical flux per surface area in a trench increases with decreasing the aspect ratio. The ...

Indole-3-glycerol phosphate synthase catalyzes the terminal ring closure step in tryptophan biosynthesis. In this paper, we compare the results from molecular dynamics (MD) simulations of enzyme-bound substrate at 298, 333, 363, and 385 K and the enzyme-bound intermediate at 385 K, solvated in TIP3P water box with a CHARMM force field. Results from MD simulations agree with experimental studies...

The non-equilibrium dynamics of three paradigmatic models for two-dimensional systems with quenched disorder is studied with a focus on the existence and analysis of a growing length scale during aging at low temperatures: 1) The random bond Ising ferromagnet, 2) the Edwards-Anderson model for a spin glass, 3) the solid-on-solid model on a disordered substrate (equivalent to the sine-Gordon mod...

The presence of a substrate can alter the equilibrium state of another material near their common boundary. Examples include wetting and interfacial premelting. In the latter case, temperature gradients induce spatial variations in the thickness of the premelted film that reflect changes in the strength of the repulsion between the substrate and the solid. We show that the net thermomolecular f...