a thin film of epinephrine (ep) was electrochemically deposited on the surface of glassy carbon electrode previously activated in nahco3 solution. the cyclic voltammograms of the modified electrode indicate that the surface confined ep are strongly dependent on the solution ph, as expected for quinone/hydroquinone functionalities. the ep-modified glassy carbon electrode exhibited catalytic acti...

the catalytic oxidation of toluene over copper oxide supported on natural diatomite was investigated. the catalyst was prepared by the wet impregnation method and characterized by using the brunauer emmett teller (bet), field emission scanning electron microscopy (fesem), x-ray diffraction (xrd), x-ray fluorescence (xrf) and temperature-programmed reduction (tpr) analysis. the highest catalytic ...

nowadays, palladium compounds due to their especial characteristics used in different industries, mainly in electrical power sources and chemical productions as a catalyst. therefore, pd concentration is increasing in our around that can be contaminant our environment due its toxic effects. in this work, a simple, selective and rapid flow injection method of analysis (fia) has been developed fo...

A new sensitive sensor was fabricated for simultaneous determination of codeine and acetaminophen based on 4-hydroxy-2-(triphenylphosphonio)phenolate (HTP) and multiwall carbon nanotubes paste electrode at trace levels. The sensitivity of codeine determination was deeply affected by spiking multiwall carbon nanotubes and a modifier in carbon paste. Electron transfer coefficient, α, catalytic el...

A simple and sensitive kinetic-spectrophotometric method is described for the determination of vanadium and the possible mechanism of catalytic reaction is proposed. The method is based on the vanadium(V)-catalyzed oxidation of 1,8-diaminonaphthalene (DNA) by potassium bromate (Tiron as activator) at pH 3.8 and 40 degrees C. The reaction was monitored spectrophotometrically by measuring the inc...