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The temperature-dependent structural changes in 1-butyl-3-methylimidazolium tetrafluoride([Bmim]FeCl4)magnetic ionic liquid(MIL)were investigated by using in-situ X-ray absorption fine structure(XAFS)combined with Raman spectroscopy and DFT calculations.XAFS re sults revealed that the coordination number and bond length of Fe-Cl in the anion of[Bmim]FeCl4 MIL decreased with increments in temperature.These results directly reflected the dissociation of tetrahedral structure[FeCl4]^-,and the formation of bridge-chain[Fe2 Cl5]^+,and[FeCl2]^+species in the anion of[Bmim]FeCl4 MIL.These behaviors indicated that[FeCl4]^-dissociation was endothermic,and was promoted by increased temperature.The results obtained through XAFS were in agreement with those obtained through Raman spectroscopy and DFT calculations. 相似文献
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Fangling Lu Zengzhuan Yang Tao Wang Tianhao Wang Yuying Zhang Yong Yuan Aiwen Lei 《中国化学》2019,37(6):538-538
The inside cover picture shows an electrochemical oxidative Csp3‐H/S‐H activation with hydrogen evolution for the synthesis of tetrasubstituted olefins. This method features very high atom economy, besides hydrogen gas, under the base‐free, transition met‐al‐free, and oxidants‐free conditions, no other by‐products were generated. More details are discussed in the article by Lei et al. on page 547–551.
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在D3d晶场下利用Oh点群表象方法,构造了d6电子系的完全能量矩阵.使用全组态相互作用方法计算了RbFeCl3晶体中Fe2+的电子光谱和零场分裂因子,其计算结果与观测数据一致. 相似文献
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Huaili Qin Zhenguang Zhang Meng Feng Fangling Gong Shimin Zhang Mingshu Yang 《Journal of Polymer Science.Polymer Physics》2004,42(16):3006-3012
The photo‐oxidative degradation of polyethylene/montmorillonite (PE/MMT) nanocomposite and microcomposite has been investigated. It has been found that the rate of photo‐oxidative degradation of PE/MMT nanocomposite and PE/Mn+MMT (where Mn+ stands for multivalent transition metal cation) microcomposites is much faster than that of pure PE. For the PE/MMT nanocomposite, the acceleration of photo‐oxidative degradation is due to the influence of MMT and ammonium ion, in which the influence of ammonium is primary. The decomposition of ammonium ion may create acidic sites on layered silicates; meanwhile, the complex crystallographic structure and habit of clay minerals could also result in some active sites. The reversible photo‐redox reaction of transition metal cations has a catalytic effect in the degradation of the polymer matrix. All these catalytic active sites can accept single electrons from donor molecules of polymer matrix and induce the formation of free radical upon UV irradiation. The generation of free radical leads to the oxidization and break of molecular chain. Thus, the materials suffer degradation and their mechanical strength decreases. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3006–3012, 2004 相似文献
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本文用从头计算方法研究了一氧化碳与卡宾加成反应的机理,得到了反应具有活化能的结论,且反应表现为亲核性。 相似文献
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Xiaoyan Zhao Zhiyi Wei Fangling Du Junqing Zhu 《Applied biochemistry and biotechnology》2010,162(7):2087-2097
Suitability of reverse micelles of anionic surfactant sodium bis(2-ethyl hexyl) sulfosuccinate (AOT) and sodium dodecyl sulfate
(SDS), cationic surfactant hexadecyl trimethyl ammonium bromide (CTAB) and nonionic surfactant polyoxyethylene p-t-octylphenol (TritonX-100) in organic solvent isooctane for extraction of soy isoflavone-enriching proteins was investigated.
The results showed that the order of combined isoflavone contents was SDS>CTAB>Triton X-100>AOT, while the order of protein
recovery was SDS>AOT>TritonX-100>CTAB. As compared with ACN-HCl extraction, the total amount of isoflavones was lower than
reverse micellar extraction. Ion strength was one of the important conditions to control extraction of isoflavone-enriching
proteins with AOT reversed micelles. For the six salt systems, KNO3, KCl, MgCl2, CaCl2, NaCl, and Na2SO4, extracted fraction of isoflavone-enriching proteins was measured. Salt solutions greatly influenced the extraction efficiency
of isoflavones in an order of KNO3>MgCl2>CaCl2>KCl>NaCl>Na2SO4, while protein in an order of MgCl2>CaCl2>NaCl>KNO3>Na2SO4>KCl. 相似文献
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In this study the surface composition of 7S and 11S globulin powders from soybean proteins by aqueous buffer and reverse micelle extractions had been examined using X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Analysis by XPS revealed that the O and N atomic percentage of 7S and 11S globulin surfaces from bis(2-ethylhexyl) sodium sulfosuccinate (AOT) reverse micelle was higher than from aqueous buffer, but the C atomic percentage was lower. The O/C ratio of the 7S globulin powder from aqueous buffer and reverse micelle was similar while significant differences were obtained in the O/C ratio of the 11S globulin powder, N/C atom ratios of the 7S and 11S globulin powders and high-resolution XPS C 1s, N 1s, O 1s spectra. Powder microstructure after reverse micelle treatment showed the presence of small pores, indicating the effect of reverse micelle on the 7S and 11S globulin structure. The obtained results indicated that the reverse micelle could affect the C, O and N components on the surface of soybean proteins. 相似文献
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曾芳玲 《中国科学技术大学学报》1995,25(2):185-192
讨论边界数据与解存在性的关系,并利用Leray-Schauder度论估计解的个数 相似文献
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Fangling Lu Zengzhuan Yang Tao Wang Tianhao Wang Yuying Zhang Yong Yuan Aiwen Lei 《中国化学》2019,37(6):547-551
Tetrasubstituted olefins are significant scaffolds as they are prevalent in many biologically active compounds and versatile building blocks for organic synthesis. Herein, we report an electrochemical oxidative Csp3—H/S—H cross‐coupling reaction, in which various tetrasubstituted olefins were prepared under base‐free, transition metal‐free, and oxidants‐free reaction conditions. 相似文献