A simple and sensitive fluorimetric method for determination of antiviral drugs: ribavirin, acyclovir, and amantadine hydrochloride has been developed. The method was based on the oxidation of these drugs by cerium(IV) in presence of perchloric acid and subsequent monitoring the fluorescence of the induced cerium(III) at lambdaexcitation 255 and lambdaemission 355 nm. Different variables affect...

     In this study a new simple selective and sensitive spectrophotometric procedure for determination of Fe(III) is described. It is based on the formation of a colored complex between ferric iron and ethyl maltol, a strong and highly selective ligand for Fe(III). After mixing sample and reagent, and incubating at the room temperature, Fe(III)-ethyl maltol complex was extracted with different ...

A current problem in petrochemical industry is the elimination of crude glycerol which is 11 the by-product of biodiesel production obtained during the transesterification of vegetable oils and 12 animal fats. In this work are presented the results of characterisation of mesoporous ceria, zirconia 13 and mixed cerium-zirconium oxide modified with gold and/or copper species and their application...

The association between cerium status and risk of first acute myocardial infarction (AMI) was examined in a case-control study in 10 centres from Europe and Israel. Cerium in toenails was assessed by neutron activation analysis in 684 cases and 724 controls aged 70 years or younger. Mean concentrations of cerium were 186 and 173 microg/kg in cases and controls, respectively. Cerium was positive...

Cerium-doped lithium niobate crystals are tested for holographic recording. A photochromic effect is observed in crystals doped with cerium and manganese. But two-center recording in the sample is not as effective as in iron and manganese doubly doped crystals. Photocurrent measurements in cerium and iron singly doped crystals indicate that the photovoltaic constant in the cerium-doped crystal ...

The coupling between structural phase transformations and dislocations induces challenges in understanding the deformation behavior of metallic cerium at the nanoscale. In the present work, we elucidate the underlying mechanism of cerium under ultra-precision diamond cutting by means of molecular dynamics modeling and simulations. The molecular dynamics model of diamond cutting of cerium is est...

The construction and performance characteristics of a novel chromate ion-selective membrane sensor are described and used for determining chromium(III) and chromium(VI) ions. The sensor is based on the use of a rhodamine-B chromate ion-associate complex as an electroactive material in a poly(vinyl chloride) membrane plasticized with o-nitrophenyloctyl ether as a solvent mediator. In a phosphate...

We consider a discrete version of the Brusselator Model of the famous Belousov-Zhabotinsky reaction in chemistry. The original model is a reaction-diffusion equation and its discrete version is a coupled map lattice. We study the dynamics of the local map, which is a smooth map of the plane. We discuss the set of trajectories that escape to infinity as well as analyze the set of bounded traject...

A simple, rapid, accurate and precise spectrophotometric method is proposed for determination of pyridoxine hydrochloride (Vitamin B6) in pure form and in its pharmaceutical preparations and serum. The method is based on the oxidation-reduction reaction between vitamin B6 and cerium (IV) ion (ceric ion), then the subsequent reaction of cerium (III) with arsenazo III reagent in acidic medium in ...