排序方式: 共有75条查询结果,搜索用时 15 毫秒
71.
Chira R. Bhattacharjee Chitraniva Datta Gobinda Das Dharitri Das Paritosh Mondal Subbarao Krishna Prasad 《Liquid crystals》2013,40(7):942-950
A new zinc(II) bimetallomesogenic complex, [Zn2L2], of tridentate [ONO]-donor Schiff base ligand (L = N-(2-hydroxyethyl)-4-hexadecyloxysalicylaldimines) was synthesised and their mesomorphic and photoluminescence properties were investigated. The compounds were characterised by Fourier transform infrared spectroscopy (FTIR), 1H and 13C nuclear magnetic resonance (NMR), ultraviolet-visible spectroscopy (UV-Vis) spectroscopy, elemental analyses and fast atom bombardment (FAB) mass spectrometry. The mesomorphic behaviour of the complex was investigated by polarised optical microscopy, differential scanning calorimetry and X-ray diffraction (XRD) study. A rectangular or oblique columnar mesophase is conjectured on the basis of powder X-ray diffraction (PXRD) study. The complex is found to be blue light emitter in solution, in solid and in condensed states with broad emission maxima at ~427–464 nm. The density functional theory (DFT) calculations revealed a distorted square planar structure around each zinc(II) centre in the dinuclear framework. Time-dependent DFT spectral correlative study was undertaken to account for the electronic transition. 相似文献
72.
Ahlem Maalaoui Assia Hajsalem Nicolas Ratel-Ramond Samah Akriche 《Journal of Cluster Science》2014,25(6):1525-1539
A novel heteropolyoxometalate, Nb-substituted hexatungstate compound; (C9H8N)3[NbW5O19]·3H2O triquinolinium μ6-oxido-dodeca-μ2-oxidohexaoxido[niobium(V)pentatungsten(VI)]ate trihydrate (QNbW5) has been grown by slow evaporation method and characterized by powder X-ray and single-crystal XRD methods, NMR, IR, UV–Vis and photoluminescence spectroscopy measurements, elemental analysis and thermogravimetric analysis. Single-crystal XRD analyses show that QNbW5 crystallizes in the triclinic space group \({\text{P}}\overline{ 1}\) and its crystal structure consists of 3D grid-like network of components in a close connection through N–H···O, C–H···O and offset π···π stacking interactions between neighboring rings of quinolinium moieties. Moreover, the spectroscopic and electronic properties of QNbW5 have also been investigated showing a considerable important gap energy well confirming the semiconductor behavior and the blue photoluminescent property of reported material. In addition, the complex shows promising antimicrobial activity against four pathogenic microbes in comparison with its components alone. 相似文献
73.
Mongi Saoudi Riadh Badraoui Ahlem Chira Mohd Saeed Nouha Bouali Salem Elkahoui Jahoor M. Alam Choumous Kallel Abdelfattah El Feki 《Molecules (Basel, Switzerland)》2021,26(16)
In our study, Allium subhirsutum L. (AS) was investigated to assess its phenolic profile and bioactive molecules including flavonoids and organosulfur compounds. The antioxidant potential of AS and wound healing activity were addressed using skin wound healing and oxidative stress and inflammation marker estimation in rat models. Phytochemical and antiradical activities of AS extract (ASE) and oil (ASO) were studied. The rats were randomly assigned to four groups: group I served as a control and was treated with simple ointment base, group II was treated with ASE ointment, group III was treated with ASO ointment and group IV (reference group; Ref) was treated with a reference drug “Cytolcentella® cream”. Phytochemical screening showed that total phenols (215 ± 3.5 mg GAE/g) and flavonoids (172.4 ± 3.1 mg QE/g) were higher in the ASO than the ASE group. The results of the antioxidant properties showed that ASO exhibited the highest DPPH free radical scavenging potential (IC50 = 0.136 ± 0.07 mg/mL), FRAP test (IC50 = 0.013 ± 0.006 mg/mL), ABTS test (IC50 = 0.52 ± 0.03 mg/mL) and total antioxidant capacity (IC50 = 0.34 ± 0.06 mg/mL). In the wound healing study, topical application of ASO performed the fastest wound-repairing process estimated by a chromatic study, percentage wound closure, fibrinogen level and oxidative damage status, as compared to ASE, the Cytolcentella reference drug and the untreated rats. The use of AS extract and oil were also associated with the attenuation of oxidative stress damage in the wound-healing treated rats. Overall, the results provided that AS, particularly ASO, has a potential medicinal value to act as effective skin wound healing agent. 相似文献
74.
In this article, numerical solution for the Rosenau-RLW equation in 2D is considered and a conservative Crank–Nicolson finite difference scheme is proposed. Existence of the numerical solutions for the difference scheme has been shown by Browder fixed point theorem. A priori bound and uniqueness as well as conservation of discrete mass and discrete energy for the finite difference solutions are discussed. Unconditional stability and a second-order accuracy on both space and time of the difference scheme are proved. Numerical experiments are given to support our theoretical results. 相似文献
75.
We prove that every weak-local derivation on a C*-algebra is continuous, and the same conclusion remains valid for weak*-local derivations on von Neumann algebras. We further show that weak-local derivations on C*-algebras and weak*-local derivations on von Neumann algebras are derivations. We also study the connections between bilocal derivations and bilocal*-automorphism with our notions of extreme-strong-local derivations and automorphisms. 相似文献