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1.
Abstract

A green and efficient methodology has been developed for the direct conversion of aryl aldehydes to the corresponding tert-butyl peresters. The reaction has been carried out in absence of any solvent and the sunlight is used as the green source of energy. In this reaction tetrabutylammonium iodide (TBAI) acts as the mild organo catalyst and tert-butyl hydroperoxide (TBHP) serve as the source of tert-butyl group.  相似文献   
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The electrolysis of water for hydrogen generation has shown immense promise as an energy conversion technology for the green energy economy.Two concurrently occ...  相似文献   
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Journal of Thermal Analysis and Calorimetry - Being motivated from the recent developments in biomicrofluidics, a mathematical model is presented to analyze the two-layered electrothermal flow via...  相似文献   
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Noncollinear difference frequency mixing of dye laser and Nd:YAG second harmonic (fundamental) radiation from a commercial laser system is employed for the generation of 2.7–5.3 μm (1.6–1.7 μm) radiations in a flux-grown KTiOAsO1 crystal. The generated radiation is used to scan the methane absorption in the fundamental (v 3) and its first overtone (2v 3) band at pressure 90 torr in a laboratory made single pass gas cell of length 33 cm.  相似文献   
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Two new square-planar Ni(II) complexes, [NiL1(NCS)] (1) and [NiL2(N3)] (2) have been synthesized with the unsymmetrical tridentate Schiff base ligands [(CH3)2NCH2CH2N=C(CH3)CH=C(OH)(C6H5)], L 1 H, derived from benzoylacetone and 2-dimethylaminoethylamine and [(CH3CH2)2NCH2CH2N=C(CH3)CH=C(OH)(C6H5)], L 2 H, derived from benzoylacetone and 2-diethylaminoethylamine, respectively. The complexes have been characterized by elemental analysis, FT-IR, UV-Vis spectroscopy, electrochemical and thermal methods (where applicable). Structures have been established by the single-crystal X-ray diffraction technique which reveals the discrete nature of the complexes in which the metal centers adopt a distorted square planar geometry. Coordination environments of the metal ions in the complexes are satisfied with two different unsymmetrical Schiff base ligands having similar N2O donor sets and a terminal pseudohalide anion (thiocyanate for 1 and azide for 2).  相似文献   
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研究热辐射对多孔非线性收缩平面上磁流体动力学(MHD)流动和热传导的影响.假设收缩平面的速度和横向磁场,按离原点距离的幂函数而变化;又假设粘性按与其有关的温度的反函数变化,热传导率按温度的线性函数变化.通过广义相似变换,将偏微分方程的控制方程,简化为耦合的非线性常微分方程,然后通过有限差分法进行数值求解.在不同的参数取值下,得到速度和温度分布,以及多孔平面上表面摩擦因数和热传导率的数值结果.  相似文献   
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A new end-to-end (EE) doubly azido bridged dinuclear complex [Cu2L21,3-N3)2] (1) [where L = (E)-4-(2-(dimethylamino)ethylimino)-1,1,1-trifluoropentan-2-one)] has been synthesized and characterized by elemental and spectroscopic techniques. Single crystal X-ray diffraction analysis reveals that the dimeric complex possesses a center of inversion. Each copper atom in 1 is in a distorted square pyramidal geometry with a CuN4O chromophore as revealed from the τ value, 0.19. The four basal positions are occupied by two imine N and one keto O atom of the Schiff base and one N atom from the azide anion. Another N atom from a coordinated azide occupies the apical position. Temperature dependent magnetic susceptibility of 1 was fitted using the Bleaney–Bowers expression which led to the parameters J = 13.6 cm−1 and R = 3.4 × 10−5. It indicates a ferromagnetic interaction through the double azido bridges connecting the individual copper Schiff base units.  相似文献   
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