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31.
《Journal of Coordination Chemistry》2012,65(7):1212-1220
A tetranuclear Zn(ΙΙ) complex, [Zn4L2(OAc)2(CH3OH)2] with an unsymmetric Salen-type bisoxime (H3L?=?6-hydroxy-4′,6′-dibromo-2,2′-[ethylenediyldioxybis(nitrilomethylidyne)]diphenol), has been synthesized and structurally characterized. There are two kinds of coordination geometry (trigonal bipyramidal and square pyramidal) in the Zn(ΙΙ) complex. The molecule has serious distortion probably from the asymmetry. The complex exhibits blue emission with the maximum emission wavelength λ max?=?423?nm when excited with 340?nm. 相似文献
32.
《Journal of Coordination Chemistry》2012,65(21):3764-3771
The crystal structure of [Zn2(2-pmOpe)2Cl4] (2-pmOpe?=?diethyl (pyridin-2-ylmethyl)phosphate) was determined by X-ray-diffraction method. The compound was also characterized by IR, far-IR, 1H, and 31P NMR spectroscopy. In this compound, 2-pmOpe is a bidentate N,O-bridging ligand and Zn(II) are slightly distorted tetrahedral ZnNOCl2. Zn(II) ions are doubly bridged by the 2-pmOpe ligands, resulting in a dinuclear species. The structure is stabilized by intermolecular C–H?···?O and C–H?···?Cl hydrogen bonds. The spectral properties are in agreement with the structural data. 相似文献
33.
本文发现了Zn(II)离子掺杂可以加快聚乳酸的结晶过程. 测试了三种Zn(II)盐(ZnCl2、ZnSt和ZnOAc),并与其它离子Mg(II)和Ca(II)进行对照. FT-IR以及变温拉曼光谱分析发现,经Zn(II)离子掺杂后,聚乳酸的结晶度和结晶速率均增加,差示扫描量热技术以及X射线衍射分析也进一步证实. 差示扫描量热技术测定PLA/ZnSt-0.4 wt%材料的结晶率达到22.46%,PLA/ZnOAc-0.4 wt%材料的结晶率达到24.83%. 相似文献
34.
为减少球形Ni/Al填充量并提高Ni/Al填充导电硅橡胶屏蔽效能,选取Ni/C纤维加入到此种导电橡胶中,并从导电性、屏蔽性能方面对其进行评价。实验发现Ni/C纤维的掺杂可以提高导电橡胶的导电性及屏蔽性能。当总颗粒填充量为130 phr时,掺杂纤维使导电橡胶的体积电阻率从1010Ω·cm降至1.4Ω·cm;当总颗粒填充量为240 phr时,在1.0~2.5 GHz的频段内,其屏蔽效能在90 d B以上,而未经过掺杂的仅能超过60 d B。利用面心立方堆垛结构模型计算颗粒间最小距离,结果发现导电橡胶的渗流阈值与颗粒最小间距有较为明显的相关性。 相似文献
35.
A new and efficient method has been developed for the synthesis of biologically significant 2-arylbenzimidazoles, 2-arylbenzothiazoles, and azomethines using recyclable and inexpensive polyvinyl pyrrolidone (PVP)–stabilized Ni nanoparticles in ethylene glycol at room temperature in excellent yields. 相似文献
36.
《Arabian Journal of Chemistry》2022,15(8):103949
Novel SiO2-pyrazole (SiO2-PYZ) nanocomposite was introduced for the elimination of Zn(II) and Cr(III) from oil reservoir water. Characterization analysis of prepared SiO2-PYZ nanocomposite was investigated using SEM, FTIR, TGA, XRD, TEM, and BET. Studying the effects and optimization of the parameters such as retention time, pH, initial Cr(III) and Zn(II) ions concentrations, adsorbent dosage, and temperature were examined. For kinetics investigation, the pseudo-second-order (PSO) model matches the adsorption process effectively under different operating conditions. After applying two other isotherm models (Langmuir and Freundlich), the experimental data was adequately equipped with Langmuir, R2 = 1. The thermodynamic results pointed that the adsorption of Zn(II) and Cr(III) ions was spontaneous, endothermic, and physisorption reaction. At pH 12, the influence of more than one ion, such as Ca(II) and Na(I), was checked, and the results revealed that this conjugate substance was highly selective to Cr(III). After washing with water in multiple cycles, the adsorbed material was regenerated with 0.1 M HCl and subsequently reused without deterioration in its case cavities. Interestingly, SiO2-PYZ was highly effective against sulfate-reducing bacteria (SRB) in the petroleum field. 相似文献
37.
Negar Naghavi Solange Temgoua Thibaud Hildebrandt Jean Franois Guillemoles Daniel Lincot 《Progress in Photovoltaics: Research and Applications》2015,23(12):1820-1827
The purpose of the present paper is to focus on the impact of oxygen gas partial pressure during the sputtering of i‐ZnO and ZnMgO on the transient behavior of Cu(In,Ga)Se2 (CIGSe) based solar cells parameters when a CBD‐Zn(S,O) buffer layer is used. Based on electrical characterization of cells, it is observed that the effect of light soaking is different on J–V characteristics depending on whether oxygen is or is not present during the first deposition time of the i‐ZnO or ZnMgO layers. In fact, when cells are prepared with standard i‐ZnO, the efficiencies are very low and a pronounced transient behavior is observed. However, when the first 10 nm of i‐ZnO or ZnMgO is formed by sputtered layer without adding oxygen during the process, depending on the thickness of the buffer layer, the transient effects strongly decreases. It is then possible to get stable cells reaching efficiencies quite similar to the CdS reference cells, especially with ZnMgO, without any post‐treatments. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
38.
S. S. Nath D. Chakdar G. Gope A. Talukdar D. K. Avasthi 《Journal of Dispersion Science and Technology》2013,34(7):1111-1113
We report synthesis of ZnS quantum dots by chemical method at room temperature. In this technique, ZnS quantum dots are produced by simple chemical reactions where zeolite, acts as matrix, plays the key role in controlling particle growth during synthesis. Quantum dots exhibit luminescence properties such as Zn2+ related emission, efficient low voltage electroluminescence, and super linear voltage-brightness EL characteristics. This study demonstrates the technological importance of semiconductor nanosystems prepared by low cost chemical route. 相似文献
39.
Abstract The zinc(II) complex with 2-(2-hydroxyphenyl)benzimidazole, namely [Zn(2-(2-hydroxyphenyl)benzimidazolate)2]·C2H5OH (1 · C2H5OH) has been synthesized and characterized by X-ray crystallography and photoluminescent analysis. The complex crystallizes
in monoclinic space group P21/c with cell parameters a = 10.156(1) ?, b = 25.771(3) ?, c = 9.674(1) ?, α = 90°, β = 103.641(2)°, γ = 90°, Z = 4, V = 2460.4(4) ?3. The central Zn(II) is four-coordinate and has a tetrahedral geometry. The steady-state and time-resolved photoluminescent
spectra for the title compound have also been studied. The emission property can be ascribed to ligand-centered charge-transfer
transition (LCCT) with π → π* property.
Index Abstract
A new co-crystal of Zn(II) complex of 2-(2-hydroxylphenyl)benzimidazole with ethanol solvate has been prepared, characterized
by X-ray crystallography and fluorescent studies.
相似文献
40.