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61.
Synthesis,spectroscopic characterization,thermal behaviour,in vitro antimicrobial and anticancer activities of novel ruthenium tricarbonyl complexes containing monodentate V‐shaped Schiff bases 下载免费PDF全文
The interaction of Ru3(CO)12 with a novel family of monodentate V‐shaped Schiff base ligands (L1–4; L1: (E)‐1‐(4‐((4‐bromobenzylidene)amino)phenyl)ethanone, L2: (E)‐1‐(3‐(4‐(dimethylamino)benzylideneamino)phenyl)ethanone, L3: (E)‐1‐(4‐(4‐(dimethylamino)benzylideneamino)phenyl)ethanone, L4: (E)‐1‐(3‐(3,4‐dimethoxybenzylideneamino)phenyl)ethanone) in air under atmospheric pressure afforded the novel complexes [Ru(CO)3(L1–4)2]. The parent ligands and their complexes were characterized using elemental analyses and spectroscopic techniques. In addition, the structure of the representative ligand L1 was determined using single‐crystal X‐ray analysis. The stereochemistry and theoretical optimization of the three‐dimensional geometry of the ligands and their complexes were justified. In vitro antimicrobial screening against bacterial stains Escherichia coli and Staphylococcus aureus and fungus Candida albicans was conducted. Cytotoxicity of the compounds as anti‐tumour agents was evaluated against liver carcinoma (HepG2), breast carcinoma (MCF7) and colon carcinoma (HCT‐116) cell lines relative to cisplatin and doxorubicin. The complexes showed variable in vitro cytotoxic activities against the three studied cell lines, with IC50 values less than those of cis‐platin, and thus appear to be building blocks for promising anti‐tumour agents. 相似文献
62.
Synthesis of V5+‐doped Ag/AgCl photocatalysts with enhanced visible light photocatalytic activity 下载免费PDF全文
V5+‐doped Ag/AgCl photocatalysts were prepared via the ion exchange method. The catalysts were characterized using X‐ray diffractometry, transmission electron microscopy, and energy‐dispersive X‐ray, X‐ray photoelectron, Fourier transform infrared and ultraviolet–visible spectroscopies. The V5+‐doped Ag/AgCl photocatalysts show much higher photocatalytic activities than Ag/AgCl under visible light irradiation for methyl orange (MO) decomposition. Especially, the 2.0 wt% V5+‐doped Ag/AgCl photocatalyst shows the highest photocatalytic activity and also high stability after five cycles. The MO degradation rate during each cycle is almost maintained at 97%. Electron spin resonance spectroscopy and radical trapping experiments reveal that holes play an important role in the photocatalytic process. 相似文献
63.
The investigation of the bidirectional coupling between a fluid flow and a structure motion is a growing branch of research in science and industry. Applications of the so-called fluid–structure interactions (FSI) are widespread. To improve coupled numerical FSI simulations, generic experimental benchmark studies of the fluid and the structure are necessary. In this work, the coupling of a vortex-induced periodic deformation of a flexible structure mounted behind a rigid cylinder and a fully turbulent water flow performed at a Reynolds number of Re=30 470 is experimentally investigated with a planar particle image velocimetry (PIV) and a volumetric three-component velocimetry (V3V) system. To determine the structure displacements a multiple-point laser triangulation sensor is used. The three-dimensional fluid velocity results show shedding vortices behind the structure, which reaches the second swiveling mode with a frequency of about 11.2 Hz corresponding to a Strouhal number of St=0.177. Providing phase-averaged flow and structure measurements precise experimental data for coupled computational fluid dynamics (CFD) and computational structure dynamics (CSD) validations are available for this new benchmark case denoted FSI-PfS-2a. The test case possesses four main advantages: (i) the geometry is rather simple; (ii) kinematically, the rotation of the front cylinder is avoided; (iii) the boundary conditions are well defined; (iv) nevertheless, the resulting flow features and structure displacements are challenging from the computational point of view. In addition to the flow field and displacement data a PIV-based force calculation method is used to estimate the lift and drag coefficients of the moving structure. 相似文献
64.
Controllable synthesis and characterization of ammonium polyphosphate with crystalline form V by phosphoric acid process 总被引:2,自引:0,他引:2
Gousheng Liu Wenyan Chen Xinchun Liu Jianguo Yu 《Polymer Degradation and Stability》2010,95(9):1834-12155
Ammonium polyphosphate (APP) with crystalline form V (APP-V) was synthesized by heating a mixture of 85% food-grade phosphoric acid and melamine under dry ammonia atmosphere. Effects such as raw material ratios, charging methods, dehydration temperature, condensation temperature and condensation time were investigated. Its water solubility was tested, its XRD and FTIR were characterized and compared with those of industrial APP-I and APP-II. Results showed that the prepared APP-V was insoluble in water, its XRD spectrum was the same as APP-V in literature. The molecular structures of the prepared APP-V and APP-I/APP-II were speculated and discussed in detail. 相似文献
65.
66.
Electronic Structure Research on Lattice Stability of V,Nb, and Ta by Density Functional Theory 下载免费PDF全文
The difference of energy and electronic structure of V, Nb, and Ta in different crystalline structures were investigated by different methods in density functional theory (DFT). Latticeconstants, total energies, and densities of states of these metals were calculated using the plane-wave pseudopotential method in DFT. Results were compared with those of projector augmented wave method, CALPHAD method, and experiments. Total energy and electronic structure analyses showed that valence electrons mostly transferred from s to p or d state, changing obviously with both the crystal structure and the elemental period number from V to Ta and leading to stronger cohesion, higher cohesive energy and more stable lattice of heavier metals. 相似文献
67.
含Bi(V)光催化剂由于其独特的电子/能带结构和光催化活性而引起人们的广泛关注。本文主要对以NaBiO3为代表的典型含Bi(V)等半导体化合物的制备方法,物化性质,光催化活性及光化学稳定性进行了综述。尽管其中的部分光催化剂在光催化过程中表现出极其优异的活性,然而其光化学条件下的不稳定性日益被人们所发现并被深入研究。最后,对含Bi(V)光催化剂今后的研究方向进行了展望。 相似文献
68.
L.S. Bovkun A.V. Ikonnikov V.Ya. Aleshkin K.V. Maremyanin N.N. Mikhailov S.A. Dvoretskii S.S. Krishtopenko F. Teppe B.A. Piot M. Potemski M. Orlita V.I. Gavrilenko 《Opto-Electronics Review》2019,27(2):213-218
Magnetoabsorption in far and mid IR ranges in double HgTe/CdHgTe quantum wells with inverted band structure has been studied in high magnetic fields up to 30 T. Numerous intraband and interband transitions have been revealed in the spectra and interpreted within axial 8 × 8 k·p model. Splitting of dominant magnetoabsorption lines resulting from optical transitions from hole-like zero-mode Landau level has been discovered and discussed in terms of a built-in electric field and collective phenomena. 相似文献
69.
《Comptes Rendus Physique》2019,20(3):218-227
In the automotive domain, Cooperative Localization (CLoc) is a new promising paradigm that aims at outperforming conventional Global Navigation Satellite Systems (GNSS) in terms of positioning accuracy, robustness, and service continuity, by relying on Vehicle-to-Vehicle (V2V) communications and hybrid data fusion. However, the growing number and the variety of the sensors aboard vehicles raise unprecedented challenges, especially in the context of distributed fusion approaches. This paper thus compares parametric and nonparametric Bayesian data fusion engines (e.g., based on cooperative variants of the Extended Kalman Filter (EKF) and Particle Filter (PF), respectively), while validating a CLoc scheme suitable to Vehicular Ad Hoc Networks (VANETs). More particularly, absolute position information from both onboard GNSS receiver and ITS-G5 V2V messages, as well as relative distance measurements based on the Impulse Radio–Ultra-Wideband (IR–UWB) technology, are combined into a single location solution that is hopefully more robust and more accurate than that of standalone GNSS. First, we investigate V2V ranging accuracy on a highway under real mobility conditions. In the same environment, we then provide offline validations of CLoc positioning, confirming significant performance gains through cooperation over conventional GNSS, even in case of poor initialization. In this specific context, the PF solution is thus shown to yield even better accuracy in comparison with EKF, thanks to its fine robustness against faced non-linear dynamics and non-Gaussian noise processes. Finally, we illustrate the resilience of the proposed solution under temporary GNSS denial. 相似文献
70.