Synthesis in a gel and sorption properties of N-2-sulfoethyl chitosan

A new procedure was developed for preparation of chelate amino-containing polymer N-2-sulfoethyl chitosan by synthesis in a gel through the reaction between chitosan and sodium 2-bromoethanesulfonate, yielding a polymer with the degree of substitution of up to 0.5. The structure of the resulting polymers was confirmed by 1H NMR spectroscopy. The sorption characteristics with respect to transition and alkaline-earth metal ions were determined for the cross-linked polymers. © 2013 Pleiades Publishing, Ltd

Creation of reference specimens of the sorption properties of nanoporous silica gels

A technique for the synthesis of nanoporous silica gels is developed. Reference specimens are created and an estimate of their metrological characteristics is performed. © 2013 Springer Science+Business Media New York

Structure and absorption spectra of substituted 2-hydroxy-2-trifluoromethylchroman-4-ones

UV absorption spectra of substituted 2-hydroxy-2-trifluoromethylchroman-4-ones (chromanones) in aqueous ethyleneglycol were studied. Replacement of hydrogen in the aromatic ring of the chromanones by CH3 or CF3 groups was shown to cause the molar extinction coefficients of the K, B, and C=O bands to shift from 16,160 to 27,980 and 30,250 dm3/mol·cm; from 12,750 to 17,920 and 16,130 dm3/mol·cm; and from 3850 to 3630 and 2760 dm3/mol·cm, respectively. Increasing the solution pH from 1 to 10.5 affected weakly the aromatic ring bands yet impacted greatly the chromanone carbonyl bands, causing their λmax to shift from 311-326 nm to 342-346 nm and their extinction coefficients to increase from 2760-3850 dm3/mol·cm to 9940-10,160 dm3/mol·cm. A further rise in the pH resulted in hypochromia of the carbonyl band due to the destruction of the chromanones. The results were confirmed by NMR spectroscopy and GC methods. © 2012 Springer Science+Business Media New York

Investigation of the structure of chitosan hybrid systems by pH-sensitive nitroxyl radical

Hybrid organo-inorganic materials based on the chitosan'SiO2, chitosan'Al2O3, and chitosan-cellulose systems are prepared. The structure of the surface is studied by means of EPR spectroscopy using the stable pH-sensitive nitroxyl radical, 4-dimethylamino-2-ethyl-5,5- dimethyl-2-pyridine-4-yl-2,5-dihydro-1H-imidazole-1-oxyl as adsorbed probe molecules, and the processes that occur during the formation of hybrid materials are considered. © 2011 Pleiades Publishing, Ltd

Chemistry for Sustainable Development 19 (2011) 173180 Liquid-Phase Dechlorination of Toxic Man-Made Products Using Nanodispersed Palladium Catalysts Sibunit

Abstract Studies concerning the liquid-phase catalytic reductive dechlorin ation of toxic man-made products using catalysts M/Sibunit (M = Ni, Pt, Pd) were performed. It has been demonstrated that the most pronounced activity is exhibited by catalysts based on palladium