排序方式: 共有78条查询结果,搜索用时 31 毫秒
31.
Zouaoui Setifi Fatima Setifi Lahcen El Ammari Malika El‐Ghozzi Jana Sopkov‐de Oliveira Santos Hocine Merazig Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(1):19-22
In the title compound, [Cu(C9H5N4O)Cl(C12H8N2)]n or [Cu(tcnoet)Cl(phen)]n, where phen is 1,10‐phenanthroline and tcnoet is 1,1,3,3‐tetracyano‐2‐ethoxypropenide, the axially elongated (4 + 2) coordination polyhedron around the CuII centre contains N atoms from three different tcnoet ligands. The resulting coordination polymer takes the form of sheets which are linked in pairs by a single C—H...N hydrogen bond to form bilayers. The bond lengths provide evidence for significant bond fixation in the phen ligand and extensive electronic delocalization in the tcnoet ligand, where the two –C(CN)2 units are rotated, in conrotatory fashion, out of the plane of the central C3O fragment. 相似文献
32.
Mohamed El Amine Dib Hocine Allali Amel Bendiabdellah Nawel Meliani Boufeldja Tabti 《Journal of Saudi Chemical Society》2013,17(4):381-385
In this study, antimicrobial activities of water and methanol extract, and three phenolic fractions of the roots of Arbutus unedo L. were investigated. Poor antibacterial activity against both Staphylococcus aureus and Pseudomonas aeruginosa bacteria was shown with water and methanol extract. However moderate antibacterial activity was shown by water extract and phenolic fractions against Escherichia coli and S. aureus, respectively. The phytochemical screening of roots of A. unedo revealed the presence of quinones, anthraquinones reducteurs compounds, anthocyanins, tannins and flavonoids. Quantitative analysis showed that the roots were strongly dominated by anthocyanins compounds (3.65 mg g?1) followed by total flavonoids (0.56 mg?1) and flavones & flavonols (0.17 mg g?1). 相似文献
33.
Sma?n Hocine Chérifa Rabia Mohammed M. Bettahar Michel Fournier 《Reaction Kinetics and Catalysis Letters》2003,79(2):357-364
Cs2.5M0.08H0.26PMo12O40and Cs2.5M0.08H1.26PMo11VO40(M: Ni, Fe) heteopolyanions were selectively prepared, characterized by IR, Raman, 31P NMR, XPS and XRD and tested in the ODH of cyclohexane. The salt structure, and reaction mechanism and kinetics are discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
34.
Mebarek Hocine Hadjoui Abdelhamid 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(6):573-597
The hp-version of the finite element method based on a triangular p-element is applied to free vibration of the orthotropic triangular and rectangular plates. The element's hierarchical shape functions, expressed in terms of shifted Legendre orthogonal polynomials, is developed for orthotropic plate analysis by taking into account shear deformation, rotary inertia, and other kinematics effects. Numerical results of frequency calculations are found for the free vibration of the orthotropic triangular and rectangular plates with the effect of the fiber orientation and plate boundary conditions. The results are very well compared to those presented in the literature. 相似文献
35.
Mössbauer spectroscopy can be a useful structural tool to assist crystallographic methods for site assignment when the compound under investigation contains divalent tin. The goal of this work was to show that the structure of tin(II) fluoride, also know as stannous fluoride, SnF2, could have been solved 14 years earlier if Mössbauer spectroscopic results, already known, had been used. A first attempt to solve the crystal structure, carried out by Bergerhoff in 1962 seemed to find the tin positions, however, it failed to find the positions of fluorine. Further extensive studies by Dénès et al. in the mid 1970s yielded the same results as those of Bergerhoff, despite the use of a Nonius CAD-4 automatic diffractometer, in contrast with Bergerhoff’s film work. The tin positions yielded a residual of 0.23, and Fourier difference maps showed significant electron density that could be fluorine atoms, however, their number did not match the number of fluorine atoms expected and several F-F distances were way too short. In addition, refinement using these possible fluorine positions led to no improvement of the residual factor. Finally, the crystal structure was published by McDonald et al. in 1976. It was found that the tin sublattice determined by Bergerhoff was basically correct, except that half of the tin atoms found by Bergerhoff to be on the (4b) and (4e) special Wyckoff sites were actually on the (8f) general site. A translation of the origin of the unit-cell by the [1/8, 0, 3/16] vector allows to change the tin Wyckoff sites from (4b), (4e) and (8f) to two (8f) sites, while keeping the basic spatial distribution of tin. A method has now been designed, using 119Sn Mössbauer spectroscopy, to test the suitability of some Wyckoff sites for divalent tin, using the Mössbauer spectrum. The tin(II) doublet (δ = 3.430(3) mm/s, Δ = 1.532(3) mm/s) shows that the lone pair is on a hybrid orbital, therefore, it is stereoactive, and it results that tin cannot be on either the (4b) or (4e) tin site since both an inversion center and a 2-fold axis would generate a second lone pair unless the 2-fold axis were along the tin-lone pair axis. 相似文献
36.
Faouzi Guenadil Hocine Aichaoui Coco N. Kapanda Didier M. Lambert Christopher R. McCurdy Jacques H. Poupaert 《Monatshefte für Chemie / Chemical Monthly》2011,27(7):67-80
Abstract
A simpler and efficient “green” method using solid sodium hydroxide in a solvent mixture of acetone/water was found to catalyze N-acylation of 2(3H)-benzoxazolones and 2(3H)-benzothiazolones for facile and rapid synthesis of N-acyl derivatives in excellent yields. This method was applied to the synthesis of a series of 132 compounds employing a variety of acyl chlorides. 相似文献37.
Ammonium salts, (NH4)6HPMo11MO40 (M = Ni, Co, Fe), have been investigated for the oxidation of propane, with molecular oxygen, at temperature ranging between 380 °C and 420 °Cafter in-situ pre-treatment performed at two heating rate of 5 or 9 °C/min. They were characterized by BET method, XRD, 31P NMR, UV-Vis and IR techniques. The catalysts were found active in the propane oxidation and selective to propene or acrolein, in particular for samples pre-treated with the heating rate of 9 °C/min. 相似文献
38.
Sihem Dali Youcef Mansour Dolè Kerim Hocine Ilitki Laurent El Kaïm 《Tetrahedron letters》2019,60(2):102-105
The Passerini reaction of α, β-unsaturated aldehydes affords allylic acetates which may be involved in Tsuji-Trost elimations towards conjugated dienamides. The interest of these 2,4-dienamides has been demonstrated in several TiCl4 triggered Diels-Alder reactions with N-phenylmaleimide. 相似文献
39.
Ali Ourari Imène Bougossa Sofiane Bouacida Djouhra Aggoun Ramiro Ruiz-Rosas Emilia Morallon Hocine Merazig 《Journal of the Iranian Chemical Society》2017,14(3):703-715
Novel potentially bidentate NO Schiff base ligands, HL 1 and HL 2 derived from condensation reaction of 2′-methoxyphenyl-2-ethylamine with salicylaldehyde (HL 1 ) and with 2-hydroxy-4-methoxybenzaldehyde (HL 2 ), and their nickel complexes were synthesized and characterized by usual spectroscopic techniques such as FT-IR, UV–Vis, 1H NMR, 13C NMR and elemental analysis. It was revealed that the bidentate Schiff base ligands coordinate with Ni(II) ions yielding mononuclear complexes with 1:2 (metal/ligand) stoichiometry. This result has been determined by using X-ray crystallographic technique of HL 2 and the nickel complex derived from HL 1 (Ni(II)-2L 1 ). So, the structural studies showed that the two Ni(II) complexes adopt a square-planar geometry around the central metal ion. Cyclic voltammetry studies were investigated in 0.1 M TBAP in DMF solution and indicate that the nickel complexes show one reduction wave related to Ni(II)/Ni(I) redox couple. The electrocatalytical properties of these complexes were also studied in the same electrolyte medium. Their electrocatalytic performances have been tested toward the electroreduction reaction of bromocyclopentane and iodobenzene, showing a promoted activity in the case of the Ni(II)-2L 2 complex. 相似文献
40.
Chetioui Souheila Zouchoune Bachir Merazig Hocine Bouaoud Salah-Eddine Rouag DjamilAzeddine Djukic Jean-Pierre 《Transition Metal Chemistry》2021,46(2):91-101
Transition Metal Chemistry - The ortho-substituted (E)-1-((2-methoxyphenyl)diazenyl)naphthalen-2-ol and the meta-substituted (E)-1-((3-methoxyphenyl)diazenyl)naphthalen-2-ol were, respectively,... 相似文献