French-Ukrainian Journal of Chemistry
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Co-Ni/Al2O3 Catalysts for CO2 Methanation at Atmospheric Pressure
Get PDFThe methanation of carbon dioxide under atmospheric pressure on a Co-Ni/Al2O3 catalyst containing 5 wt% of metals prepared by the impregnation method was studied. Temperature of 95% conversion CO2 for all catalysts been studied falls into range 320-450°C at conditions of SV 100ml/min, 0.1 MPa pressure, and composition of feeding gas mixture CO2 – 2%, H2 – 55%, He – 43%. Methane selectivity was sufficiently high – up to 98%
Fragments of Isothermal Sections of the Gd-Ge(Si)-Ga Systems Phase Diagrams at 800 ºC
Get PDFThe Gd-rich alloys of the Gd-Ge(Si)-Ga systems have been studied by the X-ray powder diffraction. The parts of the isothermal sections of these systems (800 0C, up to 33.3 at. % Gd) have been constructed. Four ternary compounds were found to exist here, namely, 1-GdGe1.0-0.7Ga1.0-1.3 (a-ThSi2-type structure), 2-Gd11Ge9Ga1 (Ho11Ga10), 1-GdSi0.9-0.6Ga1.1-1.4 (a-ThSi2) and 2-GdSi0.9-0.6Ga0.1-0.4 (CrB). One of these compounds (2-Gd11Ge9Ga1) is in fact the Ga-stabilized solid solution on the base of the high temperature Gd11Ge10 compound. Extended solid solutions on the base of the most Gd-{Si,Ge,Ga} binary compounds was shown to form in the Gd-Ge(Si)-Ga systems
Reaction of the α-azahetaryl-2-hydroxyacetophenones reaction with chloroacetyl chloride
Get PDFoai:ojs.kyivtoulouse.univ.kiev.ua:article/1The reaction of α-azolyl-2-hydroxyacetophenones with chloroacetyl chloride in acetonitrile in the presence of pyridine resulted in 2-chloromethyl-3-azolylchromones, while both the α-(2-pyridyl) and α-(2-quinolyl) derivatives formed the products of the subsequent intramolecular cyclization with annelation of indolizine or pyrroloquinoline ring to the chromone core
Synthesis of Benzylidene and Azo Containing Polymers for Photophisical Application
Get PDFIn the present work, the polymers built with the use of the free radical polymerization of methacrylic monomers incorporating an azobenzene side-group and monomers with benzylidene fragments have been synthesized. The polymerization was carried out in DMF with AIBN as initiator. The products of polymerization were characterized by HNMR. The results of investigations of photochemical and optical activities of the corresponding polymers are presented
X-ray Diffraction Study of the NaF – LiF – LnF3 (Ln=La,Nd) Eutectic Composition in the Liquid and Solid States
Get PDFThe ternary eutectic alloy with the composition 33 mol % NaF+53 mol % LiF+14 mol % NdF3 has been studied in the liquid and solid states using differential thermal analysis and X-ray diffraction at room and high temperatures. The obtained results demonstrate that the eutectic alloy undergoes no phase transformations at temperatures from 298 K to melting point. Analysis of RMC models of the melt indicates that there is no dense non-crystalline packing of the fluorine anions in contrast to the eutectic NaF—LiF—LaF3 melt
7th International Scientific Conference in Chemistry ‘Kiev-Toulouse’
Get PDF7th International Scientific Conference in Chemistry Kiev-Toulouse was held June 2-7, 2013 at the Department of Chemistry of the National Taras Shevchenko University of Kiev (KNU)
Investigations of Bis-chromophore Systems: Relationship between Spectral Behaviour and Charge Transfer in 2-(3-coumaroyl)-benzopyrylium Perchlorates
Get PDFThe dependence of spectral properties and interfragmental charge transfer (ICT) on excitation, relaxation and excited state deactivation of 2-(3-coumaroyl)-benzopyrylium perchlorates has been analyzed. It was found that the positions of emission bands and rate constants of radiationless deactivation linearly correlate with ICT upon excited state deactivation, and Stokes’ shifts of fluorescence demonstrate linear dependence on ICT upon structural relaxation in the excited state
Plasticizer Effect on Dielectric and Relaxation Parameters of Xanthan
Get PDFThe dielectric and relaxation properties of pure and plasticized (with water, glycerol and PPG-200) xanthan were studied by broadband dielectric relaxation spectroscopy. Within frequency range 10–107 Hz, a solid xanthan and its gels demonstrated two relaxation processes: the β-relaxation and relaxation of gel fragments formed due to xanthan/plasticizer interaction. The relaxation time decreased in the raw of plasticizers: PPG-200 > water > glycerol; the segmental dynamics of xanthan respectively grow. The ionic conductivity of gel samples increased in the following sequence: water < PPG-200 < glycerol
Thermal Decomposition of the Bromine Containing Oxyphenylimides
Get PDFThe new bromine containing oxyphenylimides are synthesized by Diels-Alder condensation from commercial products. The effect of brominating of oxyphenylimides on their thermal stability on air is assessed by dynamic thermogravimetric analysis. The possible routes of thermal decomposition of the brominated oxyphenylimides are researched with the help of thermal desorption analysis coupled with mass spectrometry and 1H NMR spectroscopy
Synthesis of Azobenzene-Containing Polymers based on Polymethacrylic Acid and their Photooptical Properties Studies
Get PDFPreparative method of synthesis of new photochromic polymers based on polymethacrylic acid by post-coupling reaction was found. Azobenzene side-chains of obtained polymers contain derivatives of different nature. Photooptical properties of polymer films, in particular the orientation under polarized light influence and the ability to orient the liquid crystal covered on them were studied