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71.
Damir A. Safin Dr. Felix D. Sokolov Sergey V. Baranov Łukasz Szyrwiel Maria G. Babashkina Elmira R. Shakirova F. Ekkehardt Hahn Henryk Kozlowski 《无机化学与普通化学杂志》2008,634(5):835-838
Reaction of the potassium salt of N‐diisopropoxyphosphinyl‐p‐bromothiobenzamide p‐BrC6H4C(S)NHP(O)(OiPr)2 ( HL ) with Ni(NO3)2 in aqueous EtOH leads to complex of formula [Ni(HL‐O)2(L‐O,S)2] ( 1 ). The structure of 1 was investigated by single crystal X‐ray diffraction analysis, IR, 1H and 31P{1H} NMR spectroscopy, MALDI and microanalysis. The nickel(II) ion in 1 has a tetragonal‐bipyramidal environment, (Oax)2(Oeq)2(Seq)2, with two neutral ligand molecules coordinated in axial positions through the oxygen atoms of the P=O groups. The equatorial plane of bipyramide is formed by two anionic ligands involving 1,5‐O,S‐coordination mode. The chelating ligands are bound in trans configuration. 相似文献
72.
Aydar Rakhmatullin Vasiliy V. Brusko Elmira R. Shcherbitskaya Ilya B. Polovov Rinat Bakirov Catherine Bessada 《Magnetic resonance in chemistry : MRC》2022,60(9):893-900
A family of three- and four-coordinated silver(I) complexes of formulas [Ag(PPh3)2L], [Ag(PPh3)L], and [AgL]n with N-thiophosphorylated thiourea and thioamide ligands of general formula RC(S)NHP(S)(OPri)2 [R = Ph, PhNH, iPrNH, tBuNH, NH2] have been studied by solid-state 109Ag and 31P CPMAS NMR spectroscopy. 109Ag NMR spectra have provided valuable structural information about Ag coordination, which is in good accordance with the available crystal structure data. The data presented in this work represent a significant addition to the available 109Ag chemical shifts and chemical shifts anisotropies. The silver chemical shift ranges for different P,S-environments and coordination state were discussed in detail. The 1J(31P–107/109Ag) and 2J(31P–31P) values were determined and analyzed. 相似文献
73.
In the current research, biodiesel production was investigated in the presence of solid catalysts of K2CO3/Al2O3 by transesterification of rapeseed oil. The specifications of produced fatty acid methyl esters like viscosity and flash point were studied, and it was noted that they complied with the requirements of ASTM D6751. In addition, the kinetic and thermodynamic parameters were explored considering the temperature changes between 318.15 and 348.15 K. Mass transfer resistance (external diffusion or internal diffusion) over the catalyst was neglected with regard to theWeisz-Prater criterion and Mears criterion. The kinetic models containing Eley-Rideal, Langmuir-Hinshelwood, pseudo–first-order, pseudo–second-order, and α-order models were investigated. Corrected Akaike information criterion was utilized to find the best model fitted with the experimental data. The greatest illustration for the K2CO3/Al2O3-catalyzed reaction was the nonlinear model with an order of α = 1.287 and the activation energy of 12.12 kJ/mol. Using transition state theory (Eyring-Polanyi equation), the activation Gibbs free energy, activation enthalpy, and activation entropy were calculated at different temperatures. The equilibrium thermodynamic properties depicted that this process is endothermic and spontaneous toward biodiesel production and tends to be irreversible. 相似文献
74.
Nanomagnetic bisethylferrocene‐containing ionic liquid supported on silica‐coated iron oxide (Fe3O4@SiO2@Im‐bisethylFc [HC2O4]) as a novel catalyst was designed and synthesized. The described catalyst was recycled and used without change in the time and efficiency of the condensation reaction. The Fourier transform‐infrared spectroscopy (FT‐IR), scanning electron microscopy images, X‐ray diffraction patterns, energy‐dispersive X‐ray spectroscopy, transmission electron microscope and vibrating‐sample magnetometer results confirmed the formation of Fe3O4@SiO2@Im‐bisethylFc [HC2O4] magnetic nanoparticle. The novel bis‐coumarin derivatives were identified by 1H‐NMR, 13C‐NMR, FT‐IR and CHNS analysis. 相似文献
75.
Georgiy V. Malkov Alexey V. Shastin Yakov I. Estrin Elmira R. Badamshina Yuriy M. Mikhailov 《Macromolecular Symposia》2010,296(1):107-111
The results of the kinetic study of melt and solution polymerization at the 1,3-dipolar cycloaddition reaction of the AB2 monomer – 2-azido-4,6-bis(prop-2-yn-1-yloxy)-[1,3,5]-triazine (ABPOT) are presented in this work as well as the results of the 13C-NMR characterization of the obtained hyperbranched poly([1,2,3]-triazole-[1,3,5]-triazine)s. It is established, that the first-shell substitution effect during polyaddition process and unusual high degree of branching (up to 0.9) of polymers synthesized in melt are held. 相似文献