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11.
Lina Huang Yu Chen Yuqiang Zhao Yumin Wang Junwei Xiong Junfeng Zhang Xianghua Wu Ying Zhou 《中国化学快报》2021,31(11):2941-2944
Iron is one of the essential trace elements in the human body. It plays an important role in human biology and pathology. Deregulation of iron levels in cells is associated with disease development. In this work, we synthesized a novel near-infrared intramolecular charge transfer (ICT) based ratiometric fluorescent probe to detect Fe2+, by using naphthalimide and indole moieties as building blocks. Our work showed that the radiometric probe has excellent selectivity, sensitivity and rapid response. Moreover, we could successfully perform real-time monitoring of Fe2+ in HeLa cells and C. elegans. 相似文献
12.
Thermal behaviors of typical weak basic ion exchange resins (301 and 315) were studied with thermogravimetry, elemental analysis, and Fourier transform infrared spectrometer in this study. Results indicated that there were three stages for 301 resin mass loss, the first stage and the second stage were mainly related to the decomposition of functional group, and the third stage was the decomposition of main chain. Whereas there were two stages for 315 resin mass loss, the first stage was elimination of moisture, and the second stage was the decompositions of functional group and main chain. Moreover, the decomposition of tertiary amine had three stages, the polyamine was a continuous mass loss process, and the thermostability of tertiary amine was weaker than that of polyamine. 相似文献
13.
Junwei Zhang 《Research on Chemical Intermediates》2014,40(3):1089-1102
Photodegradations of Sulfamethazine (SMT) and Sulfametoxydiazine (SMD) in TiO2 suspension were investigated experimentally and theoretically under UV irradiation. The degradations of SMT and SMD by TiO2 photocatalysis increased with prolonging the reaction time, and three main intermediates for SMT and four main intermediates for SMD were indentified by LC/MS. The N–S bond, the C–C bond (benzene ring) in the SMT, and the N–C bond, the S–N bond and the C–O bond in the SMD, had higher frontier electron densities. Initial photodegradation of SMT proceeded mainly via the break of the N–S bond and the hydroxylation of SMT, and initial photodegradation of SMD was similar to SMT. There existed a plausible consistency between the experimental results and the theoretical calculations on the basis of results obtained. 相似文献
14.
Luocai Yi Dr. Junxiang Chen Ping Shao Dr. Junheng Huang Xinxin Peng Junwei Li Dr. Genxiang Wang Chi Zhang Prof. Zhenhai Wen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(45):20287-20294
Two-dimensional (2D) monometallic pnictogens (antimony or Sb, and bismuth or Bi) nanosheets demonstrate potential in a variety of fields, including quantum devices, catalysis, biomedicine and energy, because of their unique physical, chemical, electronic and optical properties. However, the development of general and high-efficiency preparative routes toward high-quality pnictogen nanosheets is challenging. A general method involving a molten-salt-assisted aluminothermic reduction process is reported for the synthesis of Sb and Bi nanosheets in high yields (>90 %). Electrocatalytic CO2 reduction was investigated on the Bi nanosheets, and high catalytic selectively to formate was demonstrated with a considerable current density at a low overpotential and an impressive stability. Bi nanosheets continuously convert CO2 into formate in a flow cell operating for one month, with a yield rate of 787.5 mmol cm−2 h−1. Theoretical results suggest that the edge sites of Bi are far more active than the terrace sites. 相似文献
15.
以配位聚合物凝胶为模板, 构筑均一的聚吡咯纳米线网络, 聚合后经简单处理除去模板, 得到性能优异的聚吡咯凝胶. 结果表明, 模板法合成的聚吡咯凝胶为由均一纳米线组成的三维网络结构, 具有良好的力学性能、 较大的比表面积及优异的电化学特性, 在0.28 A/g电流密度下, 比电容可达450 F/g, 在2.8 A/g电流密度下充放电1000次, 比电容仍可保持88.6%. 聚吡咯纳米线网络凝胶经葡萄糖氧化酶负载后得到柔性传感电极, 对低浓度(0.2 mmol/L)的葡萄糖具有快速响应性能, 有望用于超级电容器及生物电化学传感器等领域. 相似文献
16.
17.
Nonlinear Dynamics - This article investigates the issue of hybrid-triggered control for fuzzy Markov jump system under input saturation. First, a hybrid-triggered control scheme is presented,... 相似文献
18.
Shaowei Zhang Dr. Junwei Zhao Pengtao Ma Prof. Dr. Jingyang Niu Prof. Jingping Wang 《化学:亚洲杂志》2012,7(5):966-974
Five rare-earth–transition-metal (RE–TM) heterometal organic–inorganic hybrids based on Keggin-type silicotungstates and mixed ligands H2pzda (pzda=pyrazine-2,3-dicarboxylate) and en (en=ethylenediamine) (enH2)[Cu(en)2(H2O)]2{[Cu(en)2][Cu(en)2(H2O)][(α-SiW11 O39)RE(H2O)(pzda)]}2⋅n H2O (n≈4; RE=YIII ( 1 ), DyIII ( 2 ), YbIII ( 3 ), and LuIII ( 4 )) and [Cu(en)2(H2O)]2{[Cu(en)2]2[Cu(pzda)2][(α-H2SiW11O39)Ce(H2O)]2}⋅n H2O ( 5 ; n≈8) have been hydrothermally synthesized and structurally characterized. Compounds 1–5 all contain the dimeric mono-RE substituted Keggin [RE(α-SiW11O39)]210− subunits linked by H2pzda ligands. Interestingly, 1–4 exhibit discrete structures, in which the H2pzda ligand acts as a tetradentate ligand to bind the RE and Cu cations, whereas 5 displays a 1D double-chain architecture, in which the H2pzda ligand adopts a new pentadentate mode to connect the Ce and Cu cations. To our knowledge, 1–5 represent the first monovacant Keggin-type silicotungstates containing both RE–TM heterometals and mixed ligands. The luminescence of 2 is derived from the combination of the DyIII cations and H2pzda ligands, whereas the luminescence properties of 1 and 3–5 are attributable to the H2pzda ligands. 相似文献
19.
A class of novel chiral SO-S-type bidentate ligands based on the tert-butylsulfinyl moiety as the sole chiral source were designed and synthesized through a simple and efficient pathway. These ligands are effective catalyst precursors for the palladium-catalyzed allylic alkylation of 1,3-diphenyl-2-propenyl acetate and moderate to good stereoselectivities (up to 84% ee) were obtained. 相似文献