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91.
Feng Sheng Ni Ziqiu Feng Shanshan Zhang Zhihui Liu Shuguang Wang Runbai Hu Jiawei 《Journal of Radioanalytical and Nuclear Chemistry》2019,319(3):737-748
Journal of Radioanalytical and Nuclear Chemistry - In this study, the UiO-66/Fe3O4/GO composite was prepared by one step method for removal of cesium ions (Cs+) in water and exhibited excellent... 相似文献
92.
Aiming to obtain the more effective pathogen inhibitive ingredients and explore the influence of introducing different heterocyclic units to carvacrol and thymol esters, twenty ester derivatives with different heterocyclic units were synthesized. And the in vitro antifungal activity of title compounds against five plant pathogenic fungi was evaluated by mycelium growth rate method. The results showed that some carvacrol and thymol esters showed good to excellent antifungal activity, and compound 9d (4-bromo-5-isopropyl-2-methylphenyl picolinate) exhibited a broad antifungal spectrum. Preliminary study indicated that the introduction of furan, thiophene and pyridine unit could enhance the antifungal activity of carvacrol and thymol esters against Botrytis cinerea and a bromine atom on the para position of benzene moiety could enhance their antifungal activity. 相似文献
93.
Qingqi Huang Shanshan Zhang Huaguo Yu Huiping Liu Fanhua Xiao Huiying Liao 《Journal of polymer science. Part A, Polymer chemistry》2019,57(10):1097-1104
A series of novel phenolphthalein‐containing sulfonated poly(arylene ether phosphine oxide)s (sPAEPP) with various sulfonation degrees were synthesized by direct polycondensation. The structure of sPAEPP was confirmed by 1H‐NMR, 13C‐NMR, and IR spectroscopy. The high‐molecular weight of these polymers was determined by gel permeation chromatography (GPC). The transparent, tough, and flexible membranes could be achieved by solution casting. The macroscopic properties and microstructure of the obtained membranes were investigated in detail. The results showed that these sPAEPP membranes displayed excellent properties in terms of swelling, proton conductivity, and methanol permeability. For example, sPAEPP‐100 membrane exhibited an appropriate water uptake of 33.1%, a swelling ratio of only 11.7% (lower than 20.1% of Nafion 117), a proton conductivity of 0.11 S cm?1 (similar to that of Nafion 117) at 80 °C, and a methanol permeability of 4.82 × 10?7 cm2 s?1. Meanwhile, it also presented outstanding oxidative stability. Atomic force microscope (AFM) micrographs showed that the hydrophilic domains of the sPAEPP‐100 membrane formed connected and narrow ionic channels, which contributed to its high proton conductivity and good dimensional stability. As a result, sPAEPP‐100 membrane displays excellent application prospect for fuel cells. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 1097–1104 相似文献
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95.
Precisely Controlled Multidimensional Covalent Frameworks: Polymerization of Supramolecular Colloids
Dr. Yongguang Li Shanshan Wu Lingling Zhang Xin Xu Yajun Fang Juzhen Yi Dr. Jehan Kim Dr. Bowen Shen Prof. Myongsoo Lee Dr. Liping Huang Liwei Zhang Junhui Bao Prof. Hongbing Ji Prof. Zhegang Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(48):21709-21713
Rapid and selective removal of micropollutants from water is important for the reuse of water resources. Despite hollow frameworks with specific functionalized porous walls for the selective adsorption based on a series of interactions, tailoring a stable shape of nanometer- and micrometer-sized architectures for the removal of specific pollutants remains a challenge. Here, exactly controlled sheets, tubes, and spherical frameworks were presented from the crosslinking of supramolecular colloids in polar solvents. The frameworks strongly depended on the architecture of original supramolecular colloids. As the entropy of colloids increased, the initial laminar framework rolled up into hollow tubules, and then further curled into hollow spheres. These shape-persistent frameworks showed unprecedented selectivity as well as specific recognition for the shape of pollutants, thus contributing to efficient pollutant separation. 相似文献
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98.
Shahzad Iqbal Shanshan Yu Feng Zhao Yachen Wang Jun Tian Le Jiang Yi Du Xiaoqi Yu Lin Pu 《Tetrahedron letters》2018,59(37):3397-3400
A 1,1′-bi-2-naphthol (BINOL) based dialdehyde (R)-1 is found to exhibit selective fluorescent response towards cellular thiols, l-Cys, l-Hcy, and GSH. (R)-1 reacts with l-Trp to form a Schiff base 2 which quenches the emission of l-Trp at λ?=?340. Coordination of 2 with Zn(ll) leads to greatly enhanced emission at λ?=?530?nm. When the in situ generated 2 from the combination of the solution of (R)-1 (1.0?×?10?5?M)?+?Trp (2?equiv) +Zn(OAc)2 (2 equiv) is treated with l-Cys, l-Hcy, and GSH, different fluorescent responses at three emission wavelengths, including 340, 421 and 530?nm, are observed. This allows the in situ generated 2 to be used as a ratiometric fluorescent probe to discriminate these three biothiols. NMR study of (R)-1 with D- or l-Cys in the presence of Zn(II) shows that the unique reactivity of Cys provides basis for the selective ratiometric fluorescent response. (R)-1?+?Zn(II) also exhibits enantioselective fluorescent response toward D- and l-Cys. 相似文献
99.
Kesheng Shen Xintong Han Chuang Li Guozhen Huang Shanshan Mao Xinkui Shi 《Journal of Coordination Chemistry》2018,71(7):980-990
N,N-bis(N-methyl-2-ylmethylbenzimidazole)aniline (EtAIDB) and its transition metal complexes, [Cu(EtAIDB)Br2]·EtOH {dibromo[N,N-bis(N-methyl-2-ylmethylbenzimidazole)aniline] copper(II) ethanol} (1) and [Zn(EtAIDB)Br2] {dibromo[N,N-bis(N-methyl-2-ylmethylbenzimidazole)aniline] zinc(II)} (2), have been synthesized and characterized by elemental analysis, molar conductivity, UV–visible, and IR spectroscopy. The X-ray crystallographic studies of 1 and 2 have shown two different arrangements: 1 is distorted square-based pyramidal, while 2 can be treated as distorted tetrahedral. The cyclic voltammogram of 1 represents quasi-reversible Cu2+/Cu+ pairs. In vitro antioxidant tests showed that 1 had significant antioxidant activity against superoxide and hydroxy radicals. 相似文献
100.
Fuzhong Han Bobo Su Peifang Song Yaqiao Wang Lina Jia Shanshan Xun Minggang Hu Liwei Zou 《Tetrahedron》2018,74(40):5908-5913
A N-bromosuccinimide (NBS) mediated decarboxylative sulfonylation of β-keto acids with sodium sulfinates is developed. The transformation exhibits a broad substrate scope and good functional group tolerance. Preliminary mechanistic studies showed that this reaction is likely to proceed through a nucleophilic substitution of β-keto acid with sulfonyl bromide pathway. All synthesized β-keto sulfones were evaluated the inhibitory effect against human carboxylesterase 1 (CES1). This investigation offers an expedient strategy for efficient synthesis of β-keto sulfones that are widely present in biologically active natural products and pharmaceutical agents. 相似文献