Synthesis and Structure of a New Ruthenium(II) Clathrochelate and the Use of a Highly Porous Ceramic Material with an Immobilized Complex in the Oxidative Conversion of Methane

Kinetics and Catalysis - A new ruthenium(II) cage complex with polar terminal groups in the apical substituents has been synthesized; the molecular design of the complex contributes to the...     

Electrochemical Preconcentration of Iodide and Its Determination by Cathodic Stripping Voltammetry

The effects of some factors (the nature and structure of organic compound R, the nature of the electrode material, the composition and concentration of the supporting electrolyte, the potential and time of electrolysis) on the formation and dissolution of electrochemical concentrates of the composition I₂BrR were studied. The results obtained were used for determining iodide by cathodic stripping voltammetry in the concentration range of 6 to 500 g/L. The detection limit for iodide was found to be 0.2 g/L at an electrolysis time of 3 min.     

Anodic trifluoromethylation of 10-undecylenic acid

The electrooxidation of a (～3: 1) mixture of trifluoroacetic and 10-undecylenic acids in MeCN with an aqueous KOH addition on different anodic catalysts was studied. The oxidation of trifluoroacetate ions that forms trifluoromethyl radicals is the key stage of the process, while 10-undecylenic acid seems to be merely an acceptor of the electrogenerated radicals, i.e., shows the chemical properties characteristic of olefins. The galvanostatic electrolysis of trifluoroacetic and 10-undecylenic acids led to a mixture of the products of trifluoromethylation of the latter and the products of coupling of the formed radical species. According to a qualitative estimation, the total yield of these products was 74%.     

Trimetallic NiCoM catalysts (M = Mn,Fe, Cu) for methane conversion into synthesis gas

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New heterogeneous catalytic systems based on highly porous ceramic materials modified with immobilized d-metal cage complexes for H2 production from CH4

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Visualisation of mitochondria in living neurons with single- and two-photon fluorescence laser microscopy

In this work we investigated the relative merits of conventional single-photon confocal laser scanning fluorescence microscopy (CLSM) and two-photon laser scanning fluorescence microscopy (2p-LSM) for the study of mitochondria in living neurons. Dorsal root ganglion neurons were loaded with the mitochondrion-specific fluorescent dye JC-1, the ratio between red (J-aggregates) and green (monomer) fluorescence of which reflects mitochondrial membrane potential. Cells were illuminated at 488 nm for single-photon excitation or at 870 nm for two-photon excitation. In both modalities we found that mitochondria showed: (i) similar appearance; (ii) similar fluorescence ratio values over both whole cell bodies and individual mitochondria; and (iii) similar responses to mitochondrial uncoupler, which dropped the ratio values by 50%. However, 2p-LSM exhibited several advantages over CLSM: (i) better signal/noise ratio in the green emission channel; (ii) less phototoxicity upon repetitive scanning in the focal plane; and (iii) no significant loss of image quality upon repetitive scans in the z direction. We conclude that, while both techniques enable visualisation of individual mitochondria in living cells, 2p-LSM has significant advantages for physiological work requiring time-lapse experiments or four-dimensional reconstructions of mitochondria.     

A Novel Method for the Rapid Determination of Isonicotinic Hydrazide in Aqueous Solutions Using Reflectance Spectrophotometry and Colorimetry

A rapid method is developed for the quantitative determination of 5–35 g/L of isonicotinic hydrazide (INH, isoniazide) in aqueous media. The method is based on the formation of copper(I) oxide in the reaction of isonicotinic hydrazide with copper ions on the surface of indicator tablets and the subsequent recording of the analytical signal by reflectance spectrophotometry and colorimetry. Aluminum oxide is proposed as a solid-phase substrate for the production of indicator tablets. Isonicotinic hydrazide can be determined in the tablet form of the Isoniazid preparation.     

Simulation of the Kinetics of Plasticizer Extraction with Ethanol

The main approaches to simulation of the migration kinetics of ingredients from polymers were considered. The mathematical models used for predicting the kinetics of diffusion-controlled migration processes were analyzed.