TETRAHEDRON
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2017
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IF 2.651
Cuiling Wang,Jiaxu Yan,Mo Du,Joseph A. Burlison,Chi Li,Yanni Sun,Danqing Zhao,Jianli Liu
One step synthesis of the natural product indirubin by reductive coupling of isatin with KBH 4 is described and a possible mechanism for the reaction is proposed. Eleven indirubin derivatives were obtained easily from the corresponding substituted isatin.
研究领域:
有机化学
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药物化学
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DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2014
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IF 2.045
Jin-Qiang Liu,Si-Yu Chen,Baoming Ji
The solubility of isatin in eight pure solvents including dichloromethane, toluene, acetone, ethyl acetate, 1,4-dioxane, N,N-dimethylformamide, tetrahydrofuran, and acetonitrile were determined from (278.15 to 333.15) K at atmospheric pressure using the synthetic method. The solubility was determined by a laser monitoring observation technique and found to increase with the rise of temperature. The experimental solubilities were correlated by four models including the ideal solution model, the modified Apelblat equation, λh (Buchowski) equation, and Wilson models with the overall average percentage deviations less than 0.52% in all cases. Thermodynamic functions of the solution of isatin in these solvents including apparent standard enthalpy and entropy of solution were obtained by van’t Hoff plot, and the apparent standard Gibbs energy change of solution was also calculated.
研究领域:
物理化学
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药物化学
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产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
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2025
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IF 5.1
Chunyan Xu,Guinan Lu,Xiaoyan Zhao,Chenyi Wang
Fluorescent polymers are strong competitors in the preparation of flexible sensors due to their unique photoresponsivity, excellent processability, thermal stability, and mechanical stability. For developing the application of fluorescent polymers in the detection of amino acid, the polymers based on isatin were synthesized. The large steric hindrance of isatin groups endows the polymer with excellent solubility, so the samples could be processed into nanofibers (80–450 nm) by electrospinning. The polymer membranes exhibited bright yellow-green fluorescence at UV excited. After doping TiO 2 into electrospun membranes, the water contact angles of samples were reduced from 127° to 64°. The interstice between fibers and the hydrophilicity of the membrane facilitated the penetration of the amino acid solutions. It could be identified when the concentration of the targets were 0.03 mg/mL. The tryptophan caused fluorescence quenching of membrane due to the π-π* stacking. However, the significant hydrogen bonding of tyrosine enhanced photoluminescence emission of membrane. This work provides an effective strategy for portable and visual detection of amino acids.
研究领域:
材料科学
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分析化学
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生物传感器
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DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2021
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IF 8.742
Yongjiang Yuan,Xinming Du,Hongyu Zhang,Hui Wang,Zhe Wang
The main obstacle of anion exchange membrane fuel cell is the unsatisfactory performance of its key component anion exchange membrane. The AEMs functionalized with organometallic cations have excellent stability and comprehensive performance. Here, we report a series of durable poly (isatin biphenylene) membranes with [Cp-Fe-toluene]+organometallic cation, which have a durability of 1000 h in 1 M KOH at 60 °C, and the hydroxide conductivity of the membrane still remains 81.4%. At the same time, it has excellent dimensional stability (20.55%) and mechanical properties (56.42 MPa). Based on our rational design of [Cp-Fe-toluene]+functionalized poly (isatin biphenylene) membranes, the single cell with this membrane exhibits the peak energy density of 64.4 mW cm −2 in H 2 -air (CO 2 -free) at 60 °C. All these suggest that anion exchange membranes containing metal organic cations have potential.
研究领域:
材料科学
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能源技术
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化学工程
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产品关联
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
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2022
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IF 1.73
Yannan Wang,Yajie Wang,Maolian Guo,Tao Ban,Xiuling Zhu
Hydrocarbon-based polymer proton exchange membranes (PEMs) free of heteroatom linkages are supposed to be an attractive alternative for the most advanced perfluorosulfonic acid PEMs, but it is challenging to synthesize them. Here we disclosed a series of aliphatic chain-containing poly(isatin diphenyl-co-terphenyl)(PIDT) copolymers, which were conveniently prepared by superacid-catalyzed Friedel-Crafts polycondensation. Subsequently, the sulfonated copolymer (SPIDT) membranes were prepared by the grafting of side-chain sulfonic acid groups. Due to the formed continuous and efficient nanoscale proton transport channel, these PEMs exhibited excellent proton conductivity showing 186 mS/cm at 80°C, higher than Nafion115 (150 mS/cm). Meanwhile, the prepared membranes exhibited good oxidative stability. The residual weight of the membranes is still greater than 98 wt % after 1 h immersion in Fenton’s reagent at 80°C. Notably, the direct borohydride-hydrogen fuel cell (DBHFC) equipped with SPIDT-50 membrane as the diaphragm showed the peak power density of 71 mW•cm−2 at 25°C, which was greater than that of Nafion115 (63 mW•cm−2). Therefore, the hydrocarbon-based PEMs prepared in this study show promise for application in fuel cells.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
ORGANIC ELECTRONICS
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2021
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IF 3.721
Haoguo Yue,Xiuping Ju,Yuchang Du,Yan Zhang,Hongmei Du,Jinsheng Zhao,Junhong Zhang
Three soluble conjugated polymers named PTINS-1, PTINS-2, and PTINS-3 were synthesized via Stille coupling reaction by employing different molar feed ratios of the donor units to the acceptor units. ( E )-2,2′-dibromo-4,4′-bis(2-ethylhexyl)-[6,6′-bithieno [3,2-b]pyrrolylidene]-5,5′(4H, 4H′)-dione (TIIG, M2) was used as the acceptor unit, and 2,5-bis (trimethylstannyl)thieno [3,2-b] thiophene (M1) and tris(thienothiophene) (TTT, M3) were selected as the donor units. Electrochemical research demonstrates that three polymers could switch reversibly and stably between purple neutral states with different saturation and transparent oxidized states. Amid the three polymers, PTINS-1 exhibits the best comprehensive performance including the satisfying optical contrast of 41.28% in the visible region with the response time of coloring and bleaching in only 0.47 s and 0.93 s, respectively, and the optical contrasts up to 81.98% with the coloring and bleaching time in only 0.56 s and 1.18 s at the 1590 nm. Furthermore, the other two polymers display beyond 70% of the transmittance change in the near-infrared region (NIR), which endows three polymers with commendable prospects in NIR electrochromic applications, and deserves more attention and penetrating research.
研究领域:
材料科学
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化学
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2023
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IF 9.5
Zixin Lv,Ning Zhao,Meizi He,Qing Ju,Ge Chao,Yixin Wang,Kang Geng,Hongying Tang,Nanwen Li
Phosphoric acid (PA) leakage of PA-doped high-temperature proton exchange membranes (HT-PEMs) is pivotal for its practical application under working conditions. Here, to enhance the PA retention of HT-PEMs, the concept of microphase separation regulated by flexible long aliphatic side-chain was introduced into poly(isatin-co-p-terphenyl-imidazole) matrix (PITI-CmQ90) via direct superacid-catalyzed copolymerization from N-alkylated isatin monomer . The designed PITI-CmQ90 membranes illustrate obvious microphase separation and larger ionic domain confirmed via Small-angle X-ray scattering (SAXS) analysis suggesting wider proton transport channels. Notably, PA/PITI-C6Q90 membrane exhibits the best PA retention ability under relative humidity (RH) cycle tests at different temperatures, which mainly attributed to the excellent PA interaction through moderate ion aggregation in the microphase-separated PEM matrix verified by solid 31 P NMR. As a result, the corresponding MEA displays the most durable single-cell performance under a step-V procedure from 1.0 V to 0.1 V cycle experiments at different temperatures. Therefore, the idea of microphase separation structure on PA retention mentioned in this work helps to study the ionic-pairs interactions from the perspective of membrane microstructure and provide a new strategy to enhance the durability of PEMs.
研究领域:
材料科学
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化学工程
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电化学
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高分子科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）