polyacrylontrile synthesis, via atom transfer radical polymerization, is studied in various initiator concentrations, transitional metal catalyst and different concentrations of cubr2. the variations of monomer conversion and the lin-earity of semi-logarithmic kinetic profile which is the evidence of living polymerization and constant radical concentration in the reaction medium, were revealed ...

Thin films of LaS were prepared by using spray pyrolysis technique at 270 0 C and thickness were varied by changing the concentration of reactant solution. The films were optically characterized and their variations with film thickness were studies. It was found that thickness can be tuned by varying concentration of reactant solution. The band gap was found to vary between 2.35eV to 2.50eV. Th...

Calcium deficient nanohydroxyapatite (nanoHap) powders were synthesized by co-precipitation of calcium α-D-heptagluconate hydrate and diammonium hydrogen phosphate solutions. TEM and HRTEM images of powders after the drying of products showed that the reactant concentration affected the sizes and morphology of particles. Small changes were found in phase composition of nanoHap powders synthesiz...

The deposition of yttria-doped zirconia has been experimented systematically in various types of porous ceramic substrates by a modified chemical vapor deposition (CVD) process operating in an opposing reactant geometry using water vapor and corresponding metal chloride vapors as reactants. The effects of substrate pore dimension and structure, bulk-phase reactant concentration, reactant diffus...

Address correspondence to [email protected] ABSTRACT A very simple strategy for preparing hierarchical inorganic nanostructures under ambient aqueous conditions is presented. The hierarchical inorganic nanomaterials were obtained by simply adding a highly concentrated solution of one reactant to a solution of another reactant with low concentration. No surface-capping molecules or structure-dire...

Behavior of catalytic reactions in narrow pores is controlled by a delicate interplay between fluctuations in adsorption-desorption at pore openings, restricted diffusion, and reaction. This behavior is captured by a generalized hydrodynamic formulation of appropriate reaction-diffusion equations (RDE). These RDE incorporate an unconventional description of chemical diffusion in mixed-component...

As discussed in the previous lecture, we are interested in forcing fluid to flow in a fuel cell in order to increase the limiting current, and thus the power output of the device. The model problem considered has a steady uniform flow of fluid carrying the reactant at a constant concentration, c0, into a 2-D channel of height H. In this model we will assume that the fluid velocity profile acros...