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991.
Zhou Jiahui Jiang Feng Li Sijie Xu Zhijie Sun Wei Ji Xiaobo Yang Yue 《Journal of Solid State Electrochemistry》2019,23(7):1991-2000
Journal of Solid State Electrochemistry - Considering serious pollution from the traditional chemical synthesis process, the resource-rich, clean electrode materials are greatly desired.... 相似文献
992.
Mesoporous chitosan‐immobilized iron tetrakis(4‐carboxyphenyl)porphyrin as a model of cytochrome P‐450 enzyme for oxidation of ethylbenzene 下载免费PDF全文
Mesoporous chitosan‐grafted iron tetra (4‐carboxyphenyl) porphyrin catalyst (Fe TCPP/mesp‐CTS) was prepared and investigated as a practical model for the nano‐cavity and coordinate regulation‐catalysis(CRC) function in cytochrome P‐450 enzyme. Fe TCPP/mesp‐CTS was characterized by X‐ray Diffraction (XRD), Thermogravimetry (TG), Ultraviolet–visible spectroscopy(UV‐Vis), Ultraviolet–visible– Diffuse reflectance spectroscopy (UV‐DRS), Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT‐IR), and X‐ray photoelectron spectroscopy (XPS) techniques. The catalytic activity of Fe TCPP/mesp‐CTS for ethylbenzene oxidation was investigated and it was proved to be a better catalyst than Fe TCPP/macp‐CTS based on the ethylbenzene conversion, turnover numbers(TON), and the reusability. These results are attributed to the mesocavity and CRC of amino group in Fe TCPP/mesp‐CTS. The highest ethylbenzene conversion and yields of ketone and alcohol were 24.4% and 18.2%, respectively. 相似文献
993.
New designed DNA light switch Ruthenium complexes as DNA photocleavers and Topoisomerase I inhibitors 下载免费PDF全文
Xue‐Wen Liu Yang Xiao Wei‐Gen Peng Li‐Jin Zhao You‐Ming Shen Song‐Bai Zhang Ji‐Lin Lu 《应用有机金属化学》2018,32(4)
Two ruthenium complexes containing a new ligand phipz (phipz = 2‐(1,10‐phenanthroline)‐1H‐imidazo[4,5‐b]phenazine) were designed and synthesized. These complexes were found to inhibit the DNA supercoiled relaxation mediated by topoisomerase I (topo I), cleave DNA under irradiation and bind to calf thymus DNA through intercalative mode. Furthermore, complex 2 shows higher photocleavage activity, topo I inhibition activity and DNA affinity than complex 1 . Additionally, introduction of phenazine unit may be the reason that two complexes exhibit DNA ‘light switch’ behavior. The present work shows that two complexes might be potential as new DNA ‘light switches’, DNA photocleavers and topo I inhibitors. 相似文献
994.
Synthesis,structure and catalytic polymerization activity of half‐sandwich cyclometallated iridium complexes 下载免费PDF全文
A series of mononuclear half‐sandwich cyclometallated iridium complexes with Schiff base ligands were synthesized in good yields. Five air‐stable C,N‐chelate mode complexes were obtained smoothly through metal‐mediated C─H bond activation. Treatments of dimeric metal complexes [Cp*IrCl2]2 with ligands L1–L5 afforded the corresponding C,N‐chelate mononuclear half‐sandwich iridium(III) complexes 1 – 5 . These iridium complexes exhibit high catalytic activity for norbornene polymerization. Both steric and electronic effects of the substituted groups have influences on the behaviors of the polymerization process. All complexes were characterized using infrared and NMR spectroscopies and elemental analysis. Molecular structures of complexes 1 , 2 and 5 were further confirmed using single‐crystal X‐ray analysis. 相似文献
995.
Qi Liao Le Li Yali Yuan Bin Cheng Wei Lu Shaoyan Hou 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):251-261
The 4-sulfonylcalix[6]arene modified Fe3O4 (MFS) was characterized by FT-IR, SEM, VSM, TGA, etc., which showed that its saturation magnetization was 64.99 emu g?1 with the particle size 10–40 nm. The maximum adsorption efficiency by MFS for 2.5 mg L?1 U(VI) solution amounted to 94.39%, which was higher than that by Fe3O4 (65.22%) under its optimum adsorption conditions. The adsorption of MFS and Fe3O4 were both followed the pseudo-second order model and the Langmuir isotherm model. The Gibbs free energy change and enthalpy change revealed that the adsorption of U(VI) by MFS was a spontaneous and endothermic process. 相似文献
996.
Wei Jiang Hongping Li Sheng Yin Xin Wang Wei Liu Hui Liu Wenshuai Zhu Huaming Li 《应用有机金属化学》2016,30(9):753-758
Two hexacyanoferrate‐based ionic liquids, [C4Py]3Fe(CN)6 and [C16Py]3Fe(CN)6, were synthesized and characterized using Fourier transform infrared and mass spectroscopies and CHN analysis. They were employed as Fenton‐like catalysts in extraction and catalytic oxidative desulfurization of model oil with dibenzothiophene (DBT), benzothiophene (BT), 4,6‐dimethyldibenzothiophene (4,6‐DMDBT), 4‐methyldibenzothiophene (4‐MDBT) and 3‐methylbenzothiophene (3‐MBT) as substrates. Various polar solvents, such as ionic liquids, water and organic solvents, were applied to choose a suitable extractant. The results showed the removal of DBT reached 97.1% with [C4Py]3Fe(CN)6 as a catalyst and 1‐n‐octyl‐3‐methylimidazolium hexafluorophosphate ([C8mim]PF6) as an extractant under optimal conditions. The activity of sulfur removal followed the order DBT > 3‐MBT > BT > 4‐MDBT >4,6‐DMDBT. The effect of water content on sulfur removal was investigated by adding various concentrations of H2O2. It was found that excess water had a positive effect on sulfur removal but the catalysts were less sensitive than [FeCl4?]‐based catalysts to water. The mechanism was studied using electron spin‐resonance spectroscopy and gas chromatography–mass spectrometry. O2?? may be the active oxygen species in the catalytic oxidative desulfurization process and the oxidation products of various sulfur compounds were the corresponding sulfoxides and sulfones. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
997.
A systematic investigation on the oxidation of unsymmetric bromo-phens is presented herein, where the reaction temperature is found to be the key parameter to generate oxidation or oxidation-bromination products. The regioselective C3-brominated compounds are produced in moderate yields in the cases of 2-bromo-phen and 4-bromo-phen. Subsequent hydroxylation and decarbonylation for bromo-phds are also studied, where a series of bromo-diazafluorenones and phen-triones have been isolated. Furthermore, various chlorination products have been obtained by treating bromo-phds or bromo-phts with excess POCl3. 相似文献
998.
Russian Journal of Electrochemistry - A graphene/Au nanoparticles composite modified glassy carbon electrode (GR/AuNPs/GCE) was developed. Electrochemical behavior of acetaminophen (ACOP) at this... 相似文献
999.
1000.
We study the difference in the maximum stress on a cylinder surface σmax using the measured surface heat transfer coefficient hm instead of its average value ha during quenching. In the quenching temperatures of 200, 300, 400, 500, 600 and 800°C, the maximum surface stress σmmax calculated by hm is always smaller than σamax calculated by ha, except in the case of 800°C; while the time to reach σmax calculated by hm (fmmax) is always earlier than that by ha (famax). It is inconsistent with the traditional view that σmax increases with increasing Biot number and the time to reach σmax decreases with increasing Biot number. Other temperature-dependent properties also have a small effect on the trend of their mutual ratios with quenching temperatures. Such a difference between the two maximum surface stresses is caused by the dramatic variation of hm with temperature, which needs to be considered in engineering analysis. 相似文献