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21.
Nickel(II) and copper(II) complexes of two unsymmetrical tetradentate Schiff base ligands [Ni(Me-salabza)] (1), [Cu(Me-salabza)] (2) and [Ni(salabza)] (3), {H2salabza = N,N′-bis[(salicylidene)-2-aminobenzylamine] and H2Me-salabza = N,N′-bis[(methylsalicylidene)-2-aminobenzylamine]}, have been synthesized and characterized by elemental analysis and spectroscopic methods. The crystal structures of 2 and 3 complexes have been determined by single crystal X-ray diffraction. Both copper(II) and nickel(II) ions adopt a distorted square planar geometry in [Cu(Me-salabza)] and [Ni(salabza)] complexes. The cyclic voltammetric studies of these complexes in dichloromethane indicate the electronic effects of the methyl groups on redox potential.  相似文献   
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The use of DCC, triethylamine and 4-dimethylaminopyridine in dichloromethane provides a general and standard one-pot procedure for the O-acylation of cyclic β-dicarbonyl compound derivatives (1) with palmitic and stearic acids which have long hydrocarbon tails, to synthesis of new type of fatty acid derivative in good to excellent yields. Structure elucidation was carried out by FT-IR, 1H NMR and 13C NMR spectroscopy techniques. The acyl migration was also found in results and the corresponding structure was characterized by X-ray crystallography. A proposed mechanism was discussed for the formation of products.  相似文献   
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Journal of Solid State Electrochemistry - A facile and sensitive approach is introduced to precisely determine trace amounts of prostate specific antigen (PSA) by gold nanostructures deposited on...  相似文献   
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Journal of Solid State Electrochemistry - The increasing efforts devoted to fabricating electrochromic (EC) devices have motivated a lot of studies to develop new EC materials. Herein, we introduce...  相似文献   
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Anatase titanium dioxide nanoparticles (TiO2-NPs) were synthesized with and without gelatin via the sol-gel method. The TiO2-NPs were characterized by a number of techniques, such as thermogravimetric analysis (TGA), X-ray diffraction analysis (XRD), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FT-IR) and ultraviolet visible spectroscopy (UV-Vis). The particle sizes of the TiO2-NPs prepared with and without gelatin were ~13 and ~17 nm, respectively. The main advantage of using gelatin as a stabilizing agent is that it provides long-term stability for nanoparticles by preventing particles agglomeration. The results indicated that gelatin was a reliable green stabilizer, which can be used as a polymerization agent in the sol-gel method for synthesis of tiny size TiO2-NPs. Moreover, the composite film was prepared by synthesized TiO2-NPs nanoparticles and multi wall carbon nanotube (MWNT) on glassy carbon electrode (TiO2-MWNT/GCE). The TiO2-MWNT/GCE responded linearly to L-tryptophan (L-Trp) in the concentration of 1.0 × 10?6 to 1.5 × 10?4 M with detection limit of 5.2 × 10?7 M at 3 using amperometry. The studied sensor exhibited good reproducibility and long-term stability.  相似文献   
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Journal of Thermal Analysis and Calorimetry - In the present study, the flow field and heat transfer have been simulated numerically inside a channel. The channel is under the constant heat flux....  相似文献   
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The morphology of a quaternary blend containing a diglycidyl ether of bisphenol-A (DGEBA), a thermoplastic modifier (PMMA), a phase-separating curing agent (diaminodiphenylmethane, DDM), and a non-phase-separating curing agent (methylenebis(3-chloro-2,6-diethylaniline, MCDEA) was studied as a function of volume fraction of the thermoplastic modifier and fractional concentration of the curing agents in their mixture. It was found that using mixtures of curing agents a co-continuous morphology could be obtained at PMMA concentrations as low as 2.5 volume percent. Using FTIR spectroscopy it was proved that specific interactions are present between PMMA and individual amine curing agents. On the other hand, there was no detectable specific interaction between PMMA and DGEBA. By analyzing the micro-indentation hardness data of the cryo-fractured samples and putting forward the intrinsic hardness concept, it was proposed that the co-continuous morphology is inherently more effective than the other morphologies in changing the mechanical properties of the above-mentioned multi-component blends.  相似文献   
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