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151.
Jafar Akbari 《Comptes Rendus Chimie》2012,15(6):471-473
Task-specific ionic liquid (TSIL) bearing a sulfonic acid group in imidazolium cation (10 mol %), was found to be an effective catalyst for a Strecker-type reaction in water at room temperature. A wide variety of aldehydes/ketones, amines and TMSCN as cyanide source can be easily transformed into the corresponding α-amino nitriles. The water tolerant catalyst could be recycled five times without loss of any activity. 相似文献
152.
153.
Jafar A'zami 《代数通讯》2013,41(10):3648-3651
154.
155.
Structural and Solution Studies of two Mercury(II) Complexes with [1,3‐Bis(2‐ethoxy)benzene]triazene
Mohammad Kazem Rofouei Jafar Attar Gharamaleki Ehsan Fereyduni Abolfazl Aghaei Giuseppe Bruno Hadi Amiri Rudbari 《无机化学与普通化学杂志》2012,638(1):220-223
The reaction of [1,3‐bis(2‐ethoxy)benzene]triazene, [ HL ], with Hg(SCN)2 and Hg(CH3COO)2, resulted in the formation of the complexes [Hg L (SCN)] ( 1 ) and [Hg L 2] · CH3OH ( 2 ). They were characterized by means of X‐ray crystallography, CHN analysis, FT‐IR, 1H NMR, and 13C NMR spectroscopy. The structure of compound 1 consists of two independent complexes in which the HgII atoms are stacked along the crystallographic a axis to form infinite chains. Each HgII atom is chelated by one L ligand and one SCN ligand, whereas in compound 2 , the HgII atom is surrounded by two L ligands. In addition, 1D chains formed by metal–π interactions are connected to each other by C–H ··· π stacking interactions in the structure of 1 , which results in a 2D architecture. An interesting feature of compound 2 is the presence of C–H ··· π edge‐to‐face interactions. 相似文献
156.
157.
A simple synthesis of novel and known calix[4]resorcinarenes derivatives has been achieved by the condensation of resorcinol and different aromatic aldehydes in the presence of catalytic amounts of Fe3O4 nanoparticles under solvent-free conditions.The experimental conditions have been thoroughly optimized and established,allowing significant rate enhancements and good to excellent yields.The reactions can be run safely without using any toxic organic solvents under mild reaction conditions.The Fe3O4 nanoparticles were characterized by powdered X-ray diffraction(XRD),transmission electron microscopy(TEM) and FT-IR spectroscopy. 相似文献
158.
M. Fashandi Jafar Ahmadi 《Statistics & probability letters》2012,82(4):798-804
It is proved that the equality of Rényi entropies of upper and lower order statistics as well as upper and lower k-records is a characteristic property of symmetric distributions. Also, for Farlie-Gumbel-Morgenstern (FGM) family, it is shown that under some conditions the equality of entropies of concomitants of upper and lower order statistics as well as concomitants of upper and lower record values is a characteristic property for the uniform distribution. 相似文献
159.
The aim of this paper is to present an efficient numerical procedure for solving the two-dimensional nonlinear Volterra integro-differential
equations (2-DNVIDE) by two-dimensional differential transform method (2-DDTM). The technique that we used is the differential
transform method, which is based on Taylor series expansion. Using the differential transform, 2-DNVIDE can be transformed
to algebraic equations, and the resulting algebraic equations are called iterative equations. New theorems for the transformation
of integrals and partial differential equations are introduced and proved. The reliability and efficiency of the proposed
scheme are demonstrated by some numerical experiments. 相似文献
160.
The experimental (liquid + liquid) equilibrium (LLE) properties for two ternary systems containing (N-formylmorpholine + benzene + n-hexane), (sulfolane + benzene + n-hexane) and a quaternary mixed solvent system (sulfolane + N-formylmorpholine + benzene + n-hexane) were measured at temperature ranging from (298.15 to 318.15) K and at an atmospheric pressure. The experimental distribution coefficients and selectivity factors are presented to evaluate the efficiency of the solvents for extraction of benzene from n-hexane. The LLE results obtained indicate that increasing temperature decreases selectivity for all solvents. The LLE results for the systems studied were used to obtain binary interaction parameters in the UNIQUAC model by minimizing the root mean square deviations (RMSD) between the experimental and calculated results. Using the interaction parameters obtained, the phase equilibria in the systems were calculated and plotted. The calculated compositions based on the UNIQUAC model were found to be in good agreement with the experimental values. The result of the RMSD obtained by comparing the calculated and experimental two-phase compositions is 0.0163 for (N-formylmorpholine + benzene + n-hexane) system and is 0.0120 for (sulfolane + benzene + n-hexane) system. 相似文献