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111.
Structural Chemistry - Todays, using nano-based drug delivery systems as suitable carriers can help in controlling release of drug to target cells. In current study, multi-walled carbon nanotube... 相似文献
112.
Boehmite (BO) nanoparticles (NPs) were prepared via the injection of aqueous NaOH solution to aqueous aluminum nitrate solution at room temperature. Afterwards, a new complex of copper was immobilized on BO-NPs (Cu-Guanidine@BO-NPs). This heterogeneous nanocatalyst was used as a practical, recyclable, chemo and homoselective nanocatalyst in the organic processes, i.e. the preparation of tetrazole five-membered heterocycles and chemoselective sulfoxidation of sulfides using H2O2 as oxidant. In this sense, the prepared nanocatalyst was characterized by AAS, N2 adsorption–desorption isotherms, WDX, EDS, SEM, and TGA techniques. The reusability of this catalyst was investigated in the described organic reactions for several runs without notable loss of its catalytic activity. Moreover, all of the tetrazole and sulfoxide derivatives were isolated in high Turn Over Number (TON) and Turn Over Frequency (TOF) numbers indicating the high activity and selectivity of Cu-Guanidine@BO-NPs in the described reactions. 相似文献
113.
Calculation of Viscosity and Diffusion Coefficients for Two Binary Gaseous Mixtures Using the Semi-empirical Inversion Method
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The accurate reduced potential energies for two binary gas mixtures including benzene-methanol and methane-tetrafluoromethane at low density have been obtained by direct inversion of the viscosity collision integral equations. The kinetic theory along with the extended principle of corresponding-states has been used to calculate the viscosity and dif-fusion coefficients over a wide range of temperature and composition. Good agreements between calculated and experimental data are obtained. 相似文献
114.
Neda Djordjevic Peter Habisreuther Nikolaos Zarzalis 《Flow, Turbulence and Combustion》2012,89(2):261-274
A possible solution to ensure the stability of lean premixed flames over an extended operational range is to provide enhanced heat recirculation by employing porous inert material. A potential application of the porous burner concept is the generation of the pilot flames based on lean premixed combustion which is a prerequisite for ultra low NOx emission. For the optimization of the porous burner an experimental study investigating flame stability and emissions was conducted. In particular axial concentration profiles of the stable species and temperature within the porous burner reaction zone are presented. Furthermore the surface temperature of the burner having a 10 PPI SiSiC material was measured for various operating conditions using two colour pyrometry. 相似文献
115.
We investigate filamentation of a cw laser beam in soft matter such as colloidal suspensions and fractal gels. The process, driven by electrostriction, is strongly affected by material properties, which are taken into account via the static structure factor, and have impact on the statistics of the light filaments. 相似文献
116.
Arash Mouradzadegun Mohammad Reza Ganjali Neda Kheirandish Fatemeh Abadast 《Supramolecular chemistry》2019,31(6):377-381
In this work, for the first time, metal hydrogen phosphates and sulfates have been studied as effective solid acid catalysts for the condensation of resorcinol with aromatic and aliphatic aldehydes to give tetrameric cyclic products, resorcinarenes, which have major roles in biological and industrial activities. This catalyst has several advantages, it is non-toxic, thermally and mechanically stable, inexpensive and highly resistant against organic solvents. It increases the reaction rate about six fold and makes this method an attractive alternative to the existing methods for resorcinarene formation. Interestingly, the present catalyst exhibited a high turnover number (TON) and turnover frequency (TOF) which were even comparable with that of HCl. 相似文献
117.
Several authors have studied the Taylor expansion for the volume of geodesic balls under the exponential mapping of an analytic Riemannian manifold $ (M, {\cal G}) $ . A more general structure $ (M, D{\cal G}) $ , where D is a torsion-free and Ricci-symmetric connection, appears in several geometric situations. We study the Taylor expansion in this case, where all metric notions are Riemannian, while now the exponential mapping is induced from the connection D. We give many applications, in particular in different hypersurface theories. 相似文献
118.
Dehghan Neda Payvandy Pedram Talebi Shahram 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6615-6629
Journal of Thermal Analysis and Calorimetry - The knowledge of the thermal properties of textiles is important with regard to their vast applications in most industries. Thermal properties, as one... 相似文献
119.
Catalin Vasile Maftei Martin Heiko Franz Christian Kleeberg Ion Neda 《Molecules (Basel, Switzerland)》2021,26(11)
The substance class of the well-known Cinchona alkaloids is widened by 6′-Amino-cinchonine and 6′-Amino-cinchonidine, novel compounds which incorporate a primary amino function in the quinolinic ring system. These key intermediates open the field for a range of fruitful chemistry. Here is described a short and direct pathway for the synthesis of triazole containing derivatives of the above-mentioned substances using the [3 + 2] Huisgen cycloaddition. For this purpose, the amines were first converted into the corresponding azides. Based on this, non-substituted and silyl-protected triazoles were synthesized as examples. Furthermore, didehydrated derivatives of quincorine and quincoridine were used as addition partners, resulting in compounds that carry the quinuclidine ring of the cinchona alkaloids at both ends. Some of these compounds were examined radiographically to investigate the position of the quinuclidine ring to the triazole. The solid-state structures of compounds 10, 11 and 28 were determined by X-ray diffraction analyses. 相似文献
120.
Microchimica Acta - The authors describe the preparation of a nanocomposite (mag-MoS2-Fe3O4) that was prepared from molybdenum disulfide (MoS2) and magnetic Fe3O4 nanoparticles by a hydrothermal... 相似文献