a simple, rapid and sensitive method has been developed for determination of trances of tellurium (vi) (0.096-1.250 mg/ml) based on its catalytic effect on the reduction reaction of toluidine blue by sulfide ion at ph 4. the reaction is monitored spectrophotometrically by measuring the decrease in absorbance of the dyestuff at 628 nm by the fixed time method. the detection limit is 80 ng/ml and...

catalytic and photocatalytic reactions of (2-chloroethyl) phenyl sulfide (2-ceps), a mimic of bis (2-chloroethyl)  sulfide (i.e. sulfur mustard) were studied on the surfaces of titanium oxide. tio2 nanoparticles (anatase, rutile and mixture of 80% anatase/20% rutile) along with bulk tio2 were tested as reactive sorbents for reaction of 2-ceps at room temperature (25±0.5°c). reactions were monit...

To understand enzyme functions, identifying the catalytic residues is a usual first step. Moreover, knowledge about catalytic residues is also useful for protein engineering and drug-design. However, to experimentally identify catalytic residues remains challenging for reasons of time and cost. Therefore, computational methods have been explored to predict catalytic residues. Here, we developed...

an efficient synthesis of polyhydroquinoline derivatives was reported via four-component coupling reactions of aldehydes, 1,3-dicarbonyl ketones (dimedone or 1,3-cyclohexanedione), ethyl acetoacetate or methyl acetoacetate and ammonium acetate in the presence of a catalytic amount of nanocrystalline tio2 under solvent free conditions. the reported method is mild, rapid and has the advantages su...

objective the extensive pollution of natural ecosystems has occurred by organophosphorus pesticides, being used for improvement of crop production in agriculture. biodegradation is interested in application of multifunctional bacteria containing genetical elements which specially degrade organophosphorus compounds. in this paper the detection of two bacteria species, pseudomonas and flavobacter...

This article provides a comprehensive review of the nature of catalytic sites in MOFs. In the last decade, a number of striking studies have reported outstanding catalytic activities of MOFs. In all cases, the authors were intrigued as it was unexpected from the ideal structure. We demonstrate here that (surface) defects are at the origin of the catalytic activities for the reported examples. T...

Pd(OAc)(2) in DMSO is an effective catalyst for the aerobic oxidation of alcohols and numerous other organic substrates. Kinetic studies of the catalytic oxidation of primary and secondary benzylic alcohol substrates provide fundamental insights into the catalytic mechanism. In contrast to the conclusion reached in our earlier study (J. Am. Chem. Soc. 2002, 124, 766-767), we find that Pd(II)-me...