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101.
We have reported the synthesis of a novel salen ligand and its mononuclear Pd-salen complexes derived from 2-{[2-hydroxy-3-{[(E)-(2-hydroxyphenyl)methylidene]amino}propyl)imino]methyl}phenol. The newly synthesized and isolated Pd(ii) complexes have been identified and fully characterized by various physico-chemical studies viz., elemental analyses, IR, UV-Vis, (1)H, (13)C NMR spectroscopy, electron spray ionization mass spectrometry (ESI-MS) and TGA/DTA studies. The molecular structure of the salen ligand has been ascertained by single-crystal XRD and it is coordinated to Pd(ii) ion through two nitrogen and two oxygen atoms. The UV-Vis data clearly suggest a square-planar environment around both the Pd(ii) ions. The DNA binding studies of the synthesized compounds has been investigated by electron spectroscopy and fluorescence measurements. The results suggest that Pd(ii) complexes bind to DNA strongly as compared to the free ligand. The free salen ligand and its Pd(ii) complexes have also been tested against human hepatoma cancer cell line (Huh7) and results manifested exceptional anti-proliferative effects of the Pd(ii) complexes. The anti-proliferative activity of Pd(ii) complexes has been modulated by specific regulatory genes.  相似文献   
102.

Abstract  

The zinc(II) and cadmium(II) 2,4-dichlorophenoxyacetate salts were synthesized in mixed water–methanol environment and characterized by elemental analysis, IR spectrometry and thermal analysis coupled with mass spectrometry. The crystal structures were determined by X-ray crystallography (compound 1, [C18H18Cl4O8Zn] n : monoclinic, P21/c, a = 19.094, b = 7.378, c = 8.008, α = 90.00, β = 101.134, γ = 90.00, V = 1106.95; compound 2, [C16H14Cl4O8Cd] n : monoclinic, P21/c, a = 17.730, b = 7.293, c = 8.060, α = 90.00, β = 95.18, γ = 90.00, V = 1037.9). The structural and some thermal data about the presented cadmium salt were previously reported (Song et al. Acta Crystallogr E 62:m2397, 2006; Kobylecka et al. Thermochim Acta 482:49, 2009).  相似文献   
103.
The proximal average of a finite collection of convex functions is a parameterized convex function that provides a continuous transformation between the convex functions in the collection. This paper analyzes the dependence of the optimal value and the minimizers of the proximal average on the weighting parameter. Concavity of the optimal value is established and implies further regularity properties of the optimal value. Boundedness, outer semicontinuity, single-valuedness, continuity, and Lipschitz continuity of the minimizer mapping are concluded under various assumptions. Sharp minimizers are given further attention. Several examples are given to illustrate our results.  相似文献   
104.
The reaction of copper(II) nitrate trihydrate and 2-(2-pyridyl)benzimidazole (pybzim) leads to [Cu(pybzim)2(NO3)](NO3). The compound has been studied by IR, UV–Vis spectroscopy and X-ray crystallography. The electronic structure of the [Cu(pybzim)2(NO3)]+ cation has been calculated with the density functional theory (DFT) method. The spin-allowed doublet–doublet electronic transitions of [Cu(pybzim)2(NO3)]+ have been calculated with the time-dependent DFT method, and the UV–Vis spectrum of the title compound has been discussed on this basis.  相似文献   
105.
Journal of Thermal Analysis and Calorimetry - An use of a polymerization lamp to irradiate chemically hardened glass-ionomer materials may improve their properties and accelerate the setting time....  相似文献   
106.
In this paper, we present extensive self-consistent results of molecular dynamics (MD) simulations of diffusion and thermotransport properties of Ni–Al liquid alloys. We develop a new formalism that allows easy connection between results of the MD simulations and the real experiments. In addition, this formalism can be extended to the case of ternary and higher component liquid alloys. We focus on the temperature and composition dependence of the self-diffusion coefficients, interdiffusion coefficients, thermodynamic factor, Manning factor and the reduced heat of transport. The two latter quantities both represent measures of the off-diagonal Onsager phenomenological coefficients. The Manning factor and the reduced heat of transport can be related to experimentally obtainable quantities provided the thermodynamic factor is available. The simulation results for the reduced heat of transport show that for all compositions, in the presence of a temperature gradient, Ni tends to migrate to the cold end. This is in agreement with an available experimental study for a Ni21.5Al78.5 melt (only qualitative result is available so far).  相似文献   
107.
Recently proposed bimetallic octahedral Pt–Ni electrocatalysts for the oxygen reduction reaction (ORR) in proton exchange membrane fuel cell (PEMFC) cathodes suffer from particle instabilities in the form of Ni corrosion and shape degradation. Advanced trimetallic Pt-based electrocatalysts have contributed to their catalytic performance and stability. In this work, we propose and analyse a novel quaternary octahedral (oh-)Pt nanoalloy concept with two distinct metals serving as stabilizing surface dopants. An efficient solvothermal one-pot strategy was developed for the preparation of shape-controlled oh-PtNi catalysts doped with Rh and Mo in its surface. The as-prepared quaternary octahedral PtNi(RhMo) catalysts showed exceptionally high ORR performance accompanied by improved activity and shape integrity after stability tests compared to previously reported bi- and tri-metallic systems. Synthesis, performance characteristics and degradation behaviour are investigated targeting deeper understanding for catalyst system improvement strategies. A number of different operando and on-line analysis techniques were employed to monitor the structural and elemental evolution, including identical location scanning transmission electron microscopy and energy dispersive X-ray analysis (IL-STEM-EDX), operando wide angle X-ray spectroscopy (WAXS), and on-line scanning flow cell inductively coupled plasma mass spectrometry (SFC-ICP-MS). Our studies show that doping PtNi octahedral catalysts with small amounts of Rh and Mo suppresses detrimental Pt diffusion and thus offers an attractive new family of shaped Pt alloy catalysts for deployment in PEMFC cathode layers.

PtNi nano-octahedra with Rh and Mo dopants are highly active catalysts for the oxygen reduction reaction with excellent stability and shape integrity. We investigate the morphological, structural, and compositional evolution during stability testing.  相似文献   
108.
109.
Model polypropylene and polypropylene/low molecular weight modifier systems with identical crystalline structure but of different physical state of noncrystalline regions were analyzed. The deformation of reference material was accompanied by a cavitation phenomenon while the deformation of the polypropylene/modifier systems occurred in non‐cavitating manner. Based on X‐ray and PALS measurements the observed change of the intensity of the cavitation phenomenon during the deformation of the analyzed systems was explained. Additionally, the change of interlamellar distance (induced by introducing the modifier molecules and uniaxial stretching) was correlated with the change of average size of the free volume pores of the amorphous phase—this analysis was performed based on experimental data and theoretical estimations. It was proven that the presence of modifier reduce significantly the average size of free volume pores in relation to the system with similar interlamellar distance. Finally, the method enabling specifying the effective content of the modifier in interlamellar regions based on PALS measurements and the observed change of the value of long period was presented. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 531–543  相似文献   
110.
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