a chemically modified carbon paste electrode with 2-chlorobenzoyl ferrocene (2cbf) and carbon nanotube (2cbfcnpe) was employed to study the electrocatalytic oxidation of ascorbic acid in aqueous solution using cyclic voltammetry, square wave voltammetry and chronoamperometry. the diffusion coefficient (d = 1.42 × 10-6 cm2 s-1), and the kinetic parameter such as the catalytic rate constant (k = ...

Introduction: The secondary mineralogy of martian surface materials is consistent with aqueous alteration of mafic and ultramafic rocks [e.g., 1-3]. Alteration of mafic silicates results in the release of SiO2 into aqueous solution, followed by the precipitation of silica [4] and/or silica-rich minerals. The presence of these phases is consistent with data obtained at the Mars Pathfinder [4] an...

The kinetics of the oxidation of p-cresol by Compound II of horseradish peroxidase has been studied by the stopped flow technique at an ionic strength of 0.11 from pH 2 to 11. In acid solution the reaction is kinetically first order in jcresol, but in the alkaline region a saturation effect attributable to complex formation is observed. At very high pH an additional second order reaction betwee...

According to the unique properties and many applications of nano silver powder, it was prepared from acid leaching tail solution. The low value residual gold and silver ions were occurred with fellow heavy metals as pollutants (Fe2+, Cu 2+ and Zn2+) in acid leaching tail solution in Mouteh gold mine in Iran. Preparation of nano silver particles was achieved in two steps: first, by addition of a...

According to the unique properties and many applications of nano silver powder, it was prepared from acid leaching tail solution. The low value residual gold and silver ions were occurred with fellow heavy metals as pollutants (Fe2+, Cu 2+ and Zn2+) in acid leaching tail solution in Mouteh gold mine in Iran. Preparation of nano silver particles was achieved in two steps: first, by addition of a...

Solid-liquid extraction separation based on a speciation method was studied for selective determination of vanadium (IV) and vanadium (V). Both V (IV) and V (V) cations transform to oxo-acid anion along with pH changes in the solution. The pH values for the transition points are different from each other and the difference was utilized in the separation. In the first step, particulate samples a...

In this research, ZnO nanoparticles (NPs) were synthesized using a binary Zn(II) Schiff-base complex. The complex heat-treated to prepare ZnO nanoparticles via thermal decomposition route at a temperature of 500 °C. The formation of single-phase ZnO nanoparticles and their microstructures were studied by XRD pattern, SEM and TEM observation. The photo-degradation characteristic of the as-prepar...

We studied B adsorption on amorphous aluminum and iron hydroxides, allophane, and kaolinite as a function of pH and initial B concentration. Boron adsorption lowered the point of zero charge of all four adsorbents, implying specific adsorption (inner-sphere complexation) of B. We provided novel information on the coordination of B adsorbed at mineral-water interfaces by attenuated total reflect...