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Zengchun Xie Panpan Sun Zhi Wang Prof. Dr. Hongguang Li Longyue Yu Prof. Dr. Di Sun Mengjun Chen Yuting Bi Prof. Dr. Xia Xin Prof. Dr. Jingcheng Hao 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(25):10008-10013
Luminescent metal nanoclusters (NCs) are emerging as a new class of functional materials that have rich physicochemical properties and wide potential applications. In recent years, it has been found that some metal NCs undergo aggregation-induced emission (AIE) and an interesting fluorescence-to-phosphorescence (F-P) switching in solutions. However, insights of both the AIE and the F-P switching remain largely unknown. Now, gelation of water soluble, atomically precise Ag9 NCs is achieved by the addition of antisolvent. Self-assembly of Ag9 NCs into entangled fibers was confirmed, during which AIE was observed together with an F-P switching occurring within a narrow time scale. Structural evaluation indicates the fibers are highly ordered. The self-assembly of Ag9 NCs and their photoluminescent property are thermally reversible, making the metal–organic gels good candidates for luminescent ratiometric thermometers. 相似文献
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共轭二烯烃的聚合是配位阴离子聚合,双金属配合物是聚合的活性中心,控制单体的构象是控制聚合物结构的关键。单体在低值配位场稳定化能(LFSE)过渡金属离子,如Co~(2+)、Ti~(3+)上螯合,螯合单体具有顺式构象,所得聚合物具有顺1,4结构;在中等LFSE的过渡金属离子,如V~(3+)、Cr~(3+)上配位,配位单体具有反式构象,所得聚合物具有反1,4结构或是1,2聚合物;高LFSE值过渡金属离子不易控制活性价态,双金属配合物不够稳定,所得聚合物分子量常较低,结构规整性也常不够理想。 相似文献
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Two rare metal coordination complexes of yttrium(III) including 1,10‐phenanthroline, Y(phen)2(NO3)3 and (phenH)2[Y2(pydc)3(NO3)2·6H2O] (phen=1,10‐phenanthroline, pydc=2,6‐pyridinedicarboxylate), and a proton transfer compound (phenH+)2(pydc2?) were synthesized and characterized by elemental analysis, molar conductance, infrared spectra (IR), nuclear magnetic resonance (NMR) and thermal analysis. The proposed structures of yttrium complexes were exhibited. The in vitro biological activities of the newly synthesized complexes have also been investigated against Bacillus coli, Staphylococcus aureus and Candida albicans. The results showed that yttrium(III) complexes including 1,10‐phenanthroline exhibited better antibacterial/antifungal activity than their ligands and corresponding compounds. 相似文献
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Nanofiber membranes have huge potential applications in many areas due to their unique properties. However, the thermoplastic micro/nanofiber membranes were rarely reported. In this paper, polypropylene (PP) nanofibers were prepared by melt extrusion of immiscible blends of PP, cellulose acetate butyrate (CAB), and subsequent removal of the CAB matrix. The wet‐laid application was used to make PP nanofiber membranes and PP‐g‐MAH/nonwoven micro/nanofiber membrane. The properties of membranes including morphology, apparent density, porosity, contact‐angle, pore size distribution, and water flux were characterized. The results showed that the consequent membranes were provided with optimistic porosity and pore size distribution. Moreover, they were all with high pure water fluxes, which were superior to that of PP microporous membrane. They performed an excellent separation performance of TiO2 suspension and dyeing wastewater. The work revealed this method could be an efficient one to make thermoplastic polymer micro/nanofiber membranes, and they would have a brilliant potential application for water treatment. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Zhihui Zhao Hui Dai Xiangmei Wu Haitao Chang Xiaoming Gao Mengjun Liu Pengfei Tu 《Chemistry of Natural Compounds》2007,43(4):374-376
A pectic polysaccharide was isolated from the fruits of Ziziphus jujuba Mill. cv. jinsixiaozao Hort. and its structure was characterized by acid hydrolysis, methylation, and NMR spectroscopies.
The purified fraction Ju-B-7 had a molecular mass of over 2000 kDa. Chemical and spectroscopic analyses indicated that Ju-B-7
is composed mainly of α-1,4-linked D-galactopyranosyluronic acid and 1,2-linked L-rhamnose with a molar ratio of 8.1:1. It can significantly stimulate
spleen cell proliferation in vitro (P<0.01, 10 μmg/mL).
Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 311–312, July–August, 2007. 相似文献
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建立了测定人血浆中巴洛沙星含量的固相萃取高效液相色谱紫外检测方法。采用pH 4.5的磷酸盐缓冲液并经Waters Oasis HLB固相萃取小柱对血浆样品进行预处理。以环丙沙星作内标,以十二烷基磺酸钠溶液(取560 mL水加入3.2 g十二烷基磺酸钠)-乙腈(体积比为56∶44,用磷酸调pH至3.0)为流动相,在Diamonsil C18色谱柱(150 mm×4.6 mm,5 μm)上进行分离。方法的线性范围为25~3200 μg/L,线性关系良好(r=0.9996);巴洛沙星的检出限(S/N≥3)为5 μg/L;方法的准确度为100.3%~103.8%;平均提取回收率为57.5%~77.0%,相对标准偏差小于5.1%。方法准确、灵敏,可满足血药浓度监测和药代动力学参数测试的需求。 相似文献
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Mengjun Cui Jingya Li Ajuan Yu Jinli Zhang Yangjie Wu 《Journal of molecular catalysis. A, Chemical》2008,290(1-2):67-71
One-pot synthesis of the N,N′-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr) adduct of cyclopalladated ferrocenylimine complex 1 has been described. This complex has been successfully applied to Suzuki coupling reaction. Various aryl chlorides and boronic acids can be coupled efficiently with a mild base K3PO4·7H2O and low catalyst loadings. This system has been proven to be compatible with the sterically hindered aryl chlorides and some boronic acids leading to form di- and tri-ortho-substituted biaryls in high yields. 相似文献