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71.
Hamdi Zorgati 《Comptes Rendus Mathematique》2005,340(1):81-86
We consider a thin curved ferromagnetic film not submitted to an external magnetic field. The behavior of the film is described by an energy depending on the magnetization of the film verifying the saturation constraint. The energy is composed of an induced magnetostatic energy and an energy term with density including the exchange energy and the anisotropic energy. We study the behavior of this energy when the thickness of the curved film goes to zero. We show with Γ-convergence arguments that the minimizers of the free energy converge to the minimizers of a local energy depending on a two-dimensional magnetization. To cite this article: H. Zorgati, C. R. Acad. Sci. Paris, Ser. I 340 (2005). 相似文献
72.
Hamdi M. Hassaneen Abdelfattah Shetta Ahmad S. Shawali 《Journal of heterocyclic chemistry》1980,17(6):1185-1187
Reaction of hydrazidoyl halides 1-5 with potassium selenocyanate in ethanol produces the corresponding 2,4-disubstituted-5-iminoδ2-1,3,4-selenadiazolines, 9-13 respectively. Nitrosation of the latter yields the N-nitroso derivatives 14-17 , which decompose upon refluxing in xylene to give 2,4-disubstituted Δ2-1,3,4-selenadiazolin-5-ones in good yield. Compounds 9-13 give the respective N-acetyl derivatives 22-26 and N-benzoyl derivatives 27-31 with acetic anhydride and benzoyl chloride in pyridine. 相似文献
73.
Novel cyclohexyl‐based aminophosphine ligands and use of their Ru(II) complexes in transfer hydrogenation of ketones
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Cezmi Kayan Nermin Meriç Murat Aydemir Yusuf Selim Ocak Ak𝚤n Baysal Hamdi Temel 《应用有机金属化学》2014,28(2):127-133
Two new aminophosphines – furfuryl‐(N‐dicyclohexylphosphino)amine, [Cy2PNHCH2–C4H3O] ( 1 ) and thiophene‐(N‐dicyclohexylphosphino)amine, [Cy2PNHCH2–C4H3S] ( 2 ) – were prepared by the reaction of chlorodicyclohexylphosphine with furfurylamine and thiophene‐2‐methylamine. Reaction of the aminophosphines with [Ru(η6‐p‐cymene)(μ‐Cl)Cl]2 or [Ru(η6‐benzene)(μ‐Cl)Cl]2 gave corresponding complexes [Ru(Cy2PNHCH2–C4H3O)(η6‐p‐cymene)Cl2] ( 1a ), [Ru(Cy2PNHCH2–C4H3O)(η6‐benzene)Cl2] ( 1b ), [Ru(Cy2PNHCH2–C4H3S)(η6‐p‐cymene)Cl2] ( 2a ) and [Ru(Cy2PNHCH2–C4H3S)(η6‐benzene)Cl2] ( 2b ), respectively, which are suitable catalyst precursors for the transfer hydrogenation of ketones. In particular, [Ru(Cy2PNHCH2–C4H3S)(η6‐benzene)Cl2] acts as a good catalyst, giving the corresponding alcohols in 98–99% yield in 30 min at 82 °C (up to time of flight ≤ 588 h?1). Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Progress in optical fiber communications allows ever-increasing channel capacity for local area networks (LANs). However, there are still many problems to solve with respect to bridges interconnecting these LANs, which constitute a system bottleneck. To eliminate the bridge bottleneck in the interconnection of fiber optic LANs, a high-speed bridge using optical technology is proposed. The proposed optical bridge uses bistable optical devices, such as interference filters, as essential components of its design. As these devices can be easily fabricated, the implementation of this optical bridge is feasible. 相似文献
77.
The present paper undertakes the study of (C12H12N)2CuCl4, which is a new hybrid compound. It is synthesized and characterized by single-crystal X-ray diffraction, Hirshfeld surface analysis, and FT-IR, FT-Raman, and impedance spectroscopies. It is crystallized in the monoclinic system with C2/c space group. Its crystal structure was determined and refined down to an R value of 0.05 and a wR value of 0.14. The structure can be described by the alternation of two different, cationic–anionic layers parallel to (110) plan. This complex is assembled into 3D supramolecular architecture by hydrogen bonds (N–H…Cl, C–H…Cl) and π–π interactions. Hirshfeld surface analyses and fingerprint plots are used for decoding intermolecular interactions in the crystal network and contribution of component units for the construction of the 3D architecture. The presence of different functional groups and the nature of their vibrations were identified by FT-IR and FT-Raman spectroscopies. The material is characterized by impedance spectroscopy technique measured in 209–500 MHz frequency and 296–390 K temperature ranges. In addition, the Cole–Cole (Z? versus Z?) plots were well fitted to an equivalent circuit built up by a parallel combination of resistance (R) and constant phase elements (CPEs). The close values of activation energies obtained from the analysis of equivalent circuit data confirm that the transport is through ion hopping mechanism in the bis (4-benzylpyridinium) tetrachlorocuprate. 相似文献
78.
Temel H Ilhan S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2008,69(3):896-903
The new five macrocyclic ligands were synthesized by reaction of 2,6-diaminopyridine and various dialdehydes. Then, their copper(II) perchlorate complexes were synthesized by template effect by reaction of 2,6-diaminopyridine, Cu(ClO(4))(2).6H(2)O and aldehydes. The ligands and their complexes have been characterized by elemental analysis, IR, (1)H and (13)C NMR, UV-vis spectra, magnetic susceptibility, conductivity measurements, mass spectra. All complexes are diamagnetic and binuclear. The diamagnetic behaviour of the binuclear complexes may be explained by a very strong anti-ferromagnetic interaction in the Cu-Cu pair. 相似文献
79.
The non-centrosymmetric microporous fluorinated iron phosphate, (H3O)2[Fe4(H2O)2F4(PO4)2(HPO4)2](H2O), is endowed with properties. In fact, the thermogravimetric analysis study shows a mass loss evolution as a temperature function. The optical study was also examined by UV–vis absorption. The magnetic results reveal the appearance of a ferromagnetic behavior at low temperature (Tc = 11.64 K). 相似文献
80.
The extraction of copper(II), nickel(II) and cobalt(II) from the aqueous phase with N,N'-bis(salicylaldehydene)-1,4-bis-(m-aminophenoxy)butane (MAS), which was synthesized from 1,4-bis(m-aminophenoxy)butane and salicylaldehyde, was studied. Microanalytical data, elemental analysis, UV-visible 1H and 13C n.m.r. spectra and IR-spectra were used to confirm the structures. The extractability and selectivity of divalent cations were evaluated as a function of relationship between distribution ratio of the metal and pH or ligand concentration. Cu+2 showed the highest extractability and selectivity at pH 6.0, whereas Ni+2 and Co+2 showed at pH 9.2. The stoichiometries of the compounds formed were estimated to be CuL, CoL, NiL, where L is N,N'-bis(salicylaldehydene)-1,4-bis-(m-aminophenoxy)butane. It was concluded that MAS can effectively be used in solvent extraction of copper(II), nickel(II) and cobalt(II) from the aqeous phase to the organic phase. 相似文献