A catalytic method has been developed for the determination of microgram amounts of mercury (II) based on its catalytic effect on the rate of a ligand substitution reaction. The reaction studied involved the substitution of cyanide in hexacyanoferrate (II) by resacetophenone benzoic acid hydrazone (2’, 4’dihydroxy propiophenone benzoic acid hydrazone) and the reaction was monitored spectrophoto...

Nanostructured iron oxide powder that has been recovered from waste pickling liquor unit of steel industry was studied for oxidation catalytic applications. In this research, the powder was characterized by X-ray diffraction (XRD) and transition electron microscopy (TEM) for determination of phase structure, morphology and particle size. Furthermore, the specific surface area of the powder was ...

A kinetic-spectrophotometric procedure is reported for determination of trace amounts of Ag(I). This method is based on catalytic effect of silver ion on the oxidation of congo red by potassium peroxodisulphate at pH=3.4 and 30 oC in the presence of 1,10-phenanthroline as an activator. The reaction was followed spectrophotometrically by measuring the rate of change in absorbance ...

A specific antiserum against bovine heart catalytic subunit was used for the determination of the catalytic subunit in an enzyme-linked immunosorbent assay. Under the conditions elaborated the assay has a lower detection limit for catalytic subunit of 0.25 pmol/ml. In crude bovine heart extracts the concentration of catalytic subunit was determined by this method to be 0.18 +/- 0.02 mumol/kg we...

A catalytic polarographic method for the determination of microgram quantities of Ce(IV) is developed based on the catalytic currents of cerium(IV) in the presence of NH4Cl – NH4OH at pH 6.2 with piperazine. Piperazine produces catalytic current with Ce(IV) at peak potential -0.1 to -0.6 V vs. SCE. The procedure was applied for the estimation of Ce(IV) in water samples. The method is simple, se...

the reduction mechanism of molybdenum-methyl thymol blue (mtb)-chlorate system has been investigated in water on a mercury electrode. as this system is very sensitive for ultratrace determination of molybdenum, the actual mechanism involved was studied. electrochemical techniques, including dc tast polarography and cyclic voltammetry were employed. it is shown that, the cathodic wave of molybde...

Catalytic oxidation of thiourea has been studied at alumina modified Pt electrode using cyclic voltammetry. The results indicate the suitability of alumina modified Pt electrode for voltammetric determination of thiourea. The catalytic peak currents are linearly dependent on the thiourea concentration in the range 2.5 × 10 – 7.0 × 10 M. The usefulness of the method was tested in determination o...

A new, simple, sensitive and selective method for the simultaneous determination of trace iron and aluminum by catalytic spectrophotometry was presented, based on the catalytic effects of iron and aluminum on the discoloring reaction of xylene cyanol FF proceeded by hydrogen peroxide and potassium periodate in weak nitric acid medium. No catalytic effect was obtained in the presence of hydrogen...

A kinetic-catalytic spectrophotometric flow-injection method was developed for the rapid and sensitive determination of trace amounts of copper(II). The method is based on the catalytic effect of copper(II) on the redox reaction of cysteine with iron(III). Iron(II) produced by the catalytic reaction reacts with 2,4,6-tris(2-pyridyl)-1,3,5-triazine (TPTZ) to form the iron(II)-TPTZ complex (lambd...

The present paper describes two new, simple, rapid, selective and sensitive kinetic spectrophotometric methods for Co(II) and Sn(II) determination in solution at room temperature, based on their effect on phenyl fluorone (PF) oxidation by hydrogen peroxide in ammonia buffer. The new method was elaborated for nano amounts of Co(II) determination, based on its catalytic effect on the oxidation of...