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81.
《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
82.
M. Lachica E. Barahona 《International journal of environmental analytical chemistry》2013,93(1-4):219-221
Abstract The effect of using solution matrices in calibration standards different from those employed for the extraction steps in the determination of Cd, Cr, Cu, Ni and Zn were tested. Cu and Zn are little affected by matrix effects but, if the extractant is ammonium acetate, the use of other matrices may result in too high Cd, Cr and Ni values. 相似文献
83.
The enhanced biological activities of three Zn (II) complexes based on different 1,2,4‐triazole fungicides
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Guo‐yu Ren Jie Li Xu‐zhan Wei Jin‐hua Zhou Biao Yan Zhao‐qi Guo Ying‐hui Ren Xiao‐hong Sun Hai‐xia Ma 《应用有机金属化学》2018,32(9)
In order to screen effective fungicides, three Zn (II) complexes, [Zn L 1 4 (NO3)2]·2H2O·2EtOH ( 1 ), [Zn L 2 4 (NO3)2] ( 2 ), and [Zn L 3 4 (DMF)2](NO3)2 ( 3 ), ( L 1 = paclobutrazol, L 2 = diniconazole, and L 3 = hexaconazole), were synthesized and characterized by elemental analysis, FT‐IR spectroscopy, and single‐crystal XRD. The antifungal activities of these complexes were then evaluated against four selected fungi using the mycelial growth rate method. The resulting data indicate that all the complexes show the enhanced antifungal activities than the corresponding ligand and mixtures. And, the interactions between the metal salt and ligands in the three complexes seem to be synergistic. According to the study of the influence of the structures on the activity, complex 2 with C=C linkage and 2,4‐dichlorophenyl moieties enhances the bioactivity significantly, especially against Wheat gibberellic ( II ). Density functional theory (DFT) calculations were carried out to help explain the enhanced bioactivity of the Zn (II) complexes. Meanwhile, all complexes are excellent grow‐regulators, especially complex 3 . The resulting data show that the complexes based on triazole fungicides have the potential applications in agriculture. 相似文献
84.
《Journal of Coordination Chemistry》2012,65(11):2032-2038
A Zn(II) complex with an organoselenium substituted Schiff base, bis{2-[(benzylimino)methyl]-4,6-dihydroselenophenol}Zn(II), has been synthesized and characterized by elemental analyses and X-ray diffraction. Zn(II) is four-coordinated by two phenolate O and two imine N from two organoselenium substituted Schiff-base ligands, forming a distorted tetrahedral geometry. The title complex and its ligand were tested in vitro for their antibacterial and antitumor activity with the complex showing higher antibacterial and antitumor activities. 相似文献
85.
《Journal of Coordination Chemistry》2012,65(21):3565-3574
AbstractA new Zn(II) metal-organic framework (MOFs), [Zn(BTC)(HME)]·(DMAc)(H2O) (1, H3BTC =1,3,5-benzenetricarboxylic acid, HME?=?protonated melamine, DMAc?=?N,N-dimethylacetamide), has been synthesized under solvothermal conditions. In the structure of 1, the four-coordinate Zn(II) ions are connected by BTC3? ligands into a 3-D framework with (3)-connected utg-type topology. This MOF shows permanent porosity after lattice solvent removal with a calculated pore size distribution around 0.72?nm. With abundant N-donor sites and suitable pore size, the desolvated 1 (1a) was used as a drug carrier for the loading of anticancer drug 5-fluorouracil (5-Fu) molecules. Moderate 5-Fu loading capacity and long drug release time were observed for 1a. The computational simulation results reveal that strong H-bond interactions between the 5-Fu molecules and the nitrogen sites allow slow release of the drug 1a. In addition, the in vitro cytotoxicity of 1 and 5-Fu loaded 1a were also evaluated using MTT assays against human oral squamous cell carcinoma (SCC-251 and HSC-4). 相似文献
86.
《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
87.
The effect of incorporating self-assembled monolayers of 4-methoxybenzoic acid (MBA) on CdS quantum dot-sensitized (QDSSC) solar cells based on ZnO nanorods was evaluated. The MBA was deposited on the ZnO photoanode, with the deposition time being a process variable. Photoluminescence spectra indicated that the MBA modification can suppress the photogenerated electron–hole recombination processes and presumably passivate the surface defects. The ultraviolet photoemission spectroscopy results prove that MBA forms an energy barrier at the interface of ZnO and CdS which may retard the back transfer of electrons. Overall the inclusion of MBA imparts a weak positive enhancement of the photovoltaic performance of these QDSSCs and this is an approach that may be developed to give stronger effects using alternative chemistries. 相似文献
88.
《应用有机金属化学》2017,31(1)
An organic polymeric resin was synthesized by anchoring p ‐aminobenzoic acid onto macroporous chloromethylated polystyrene beads, and was used for Zn(II) removal from aqueous solutions. The resin exhibited an initially rapid adsorption property for Zn(II) with equilibrium time of 10 h and the maximum adsorption capability approached 184.5 mg g−1. Optimum pH was 4.5. The mechanism of adsorption was investigated using kinetic, isotherm and thermodynamic models. The adsorption kinetic data were described well by a pseudo second‐order model with R 2 of 0.997. There was a negative ΔG (−17.98 kJ mol−1) and positive ΔH (13.58 kJ mol−1). HCl solution (1.0 mol l−1) could achieve an elution rate of 100%. The experimental data were well fitted by the Thomas model with R 2 of 0.9826. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
89.
Dr. Lingxing Zeng Biyu Kang Fenqiang Luo Yixing Fang Cheng Zheng Junbin Liu Renpin Liu Xinye Li Prof. Dr. Qinghua Chen Prof. Dr. Mingdeng Wei Prof. Dr. Qingrong Qian 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(58):13411-13421
Sodium/potassium-ion batteries (SIBs/PIBs) arouse intensive interest on account of the natural abundance of sodium/potassium resources, the competitive cost and appropriate redox potential. Nevertheless, the huge challenge for SIBs/PIBs lies in the scarcity of an anode material with high capacity and stable structure, which are capable of accommodating large-size ions during cycling. Furthermore, using sustainable natural biomass to fabricate electrodes for energy storage applications is a hot topic. Herein, an ultra-small few-layer nanostructured MoSe2 embedded on N, P co-doped bio-carbon is reported, which is synthesized by using chlorella as the adsorbent and precursor. As a consequence, the MoSe2/NP-C-2 composite represents exceedingly impressive electrochemical performance for both sodium-ion batteries (SIBs) and potassium-ion batteries (PIBs). It displays a promising reversible capacity (523 mAh g−1 at 100 mA g−1 after 100 cycles) and impressive long-term cycling performance (192 mAh g−1 at 5 A g−1 even after 1000 cycles) in SIBs, which are some of the best properties of MoSe2-based anode materials for SIBs to date. To further probe the great potential applications, full SIBs pairing the MoSe2/NP-C-2 composite anode with a Na3V2(PO4)3 cathode also exhibits a satisfactory capacity of 215 mAh g−1 at 500 mA g−1 after 100 cycles. Moreover, it also delivers a decent reversible capacity of 131 mAh g−1 at 1 A g−1 even after 250 cycles for PIBs. 相似文献
90.
Cu–Zn–In–S solid solution thin films with tunable compositions and band gaps were deposited on glass substrates using a chemical spray pyrolysis approach. XRD results reveal the cubic-structured Cu–Zn–In–S films without detectable impurities. The successive shift of XRD patterns toward high-angle side of ZnS with increasing ZnS molar fraction in products proves a formation of Cu–Zn–In–S solid solutions. SEM images and EDAX analyses demonstrate homogeneous surface morphologies and adjustable compositions of Cu–Zn–In–S films, which results in film band gaps broadly tunable from 1.54 eV to 3.61 eV. These sprayed Cu–Zn–In–S solid solution thin films may find potential uses in photovoltaics and photocatalysis. 相似文献