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Ramin Ghorbani-Vaghei Davood Azarifar Ardeshir Khazaei Behrooz Maleki 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):1877-1881
1,3,5-Trisubstituted pyrazolines were converted to the corresponding pyrazoles in good yields under heterogeneous and solvent-free conditions by N,N′,N,N′-tetrabromo-benzene-1,3-disulfonylamide [TBBDA] at ambient temperature. 相似文献
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Cold expansion is a useful process for imposing compressive residual stresses around the holes in riveted and bolted connections. These stresses increase the fatigue life of holed parts. Distribution and amount of exerted residual stress dependent on various parameters as material, distance of adjacent holes, hole diameter, cold expansion ratio and plate thickness. In this study, experimental and numerical results for two different aluminum alloys and various holes distances are investigated and compared. Effects of mentioned parameters on the residual stress are studied. 相似文献
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A new environmentally benign, convenient, and facile methodology for the N-formylation of amines is reported using ultrasound irradiation under solvent- and catalyst-free conditions at room temperature. Compared with conventional methods, the main advantages of the present procedure are milder, cleaner and greener conditions, shorter reaction time, higher purity and yields, simpler work-up, and lower generation of waste or pollutions. 相似文献
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For a closed symplectic manifold with compatible Riemannian metric g we study the Sobolev geometry of the group of all diffeomorphisms on M which preserve the symplectic structure. We show that, for sufficiently large s, the metric admits globally defined geodesics and the corresponding exponential map is a non-linear Fredholm map of index zero. Finally, we show that the metric carries conjugate points via some simple examples. 相似文献
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S. J. Sabounchei V. Jodaien S. Samiee 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):473-481
Complexes of the type NBu 4 MCl 3 PR 3 R=P.Tolyl,Ph,Bu) (M = Pt, Pd) are prepared by the reaction of MCl 2 or K 2 [MCl 4 ] by phosphine ligands. Addition of NBu 4 Br or NBu 4 I to these compounds, in dichloromethane results in a redistribution of halogens and formation of all six isomers of the type MBr 3 ?XClXPR 3 X= 0, 1, 2, and 3 which have been identified by 31 P- 1 H NMR spectroscopy. The intensities show that the products are proportional to the statistical distribution. 相似文献
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One of the commonly used methods to synthesize furans is the three-component reaction among aromatic aldehyde, arylamine, and acetylenedicarboxylate. The main advantages of this work are easy reaction work-up, short reaction time, high yield and easy recyclability, reusability of the catalyst. And also basalt fiber applications are surely innovative in many industrial and economic fields, because of its good mechanical, chemical and thermal performances. 相似文献
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