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91.
Studies on the Molecular Chain Conformation Stability of Aminated Konjac Glucomannan 总被引:2,自引:0,他引:2
Konjac glucomannan (KGM) was aminated by 2-chloroethyl-amine (CEA) as reagent so as to study the influence of concentration of CEA (based on the amount of KGM), concentration of NaOH, reaction time and temperature on the extent of amination. And the molecular simulation technology was adopted to analyze the conformation stability of aminate (AKGM). The results indicate that when the amount of CEA is higher, the extent of amination is higher. The optimum concentration of NaOH, reaction time and temperature are 10% NaOH, 70 ℃ and 45 rain, respectively. IR shows KGM is successfully aminated. The conformation of AKGM is in a random clew-like shape. 相似文献
92.
Yue Ma Haiyang Li Shangjin He Hongtao Zhang Huiqi Zhang 《Journal of polymer science. Part A, Polymer chemistry》2014,52(14):1941-1952
A facile, general, and highly efficient one‐pot approach to obtain azobenzene (azo)‐containing molecularly imprinted polymer (MIP) nanoparticles with photoresponsive template binding and release properties in aqueous media is described, which involves the combined use of hydrophilic macromolecular chain transfer agent‐mediated reversible addition‐fragmentation chain transfer precipitation polymerization and easily available water‐insoluble azo functional monomers. The resulting azo‐containing MIPs were characterized with dynamic laser scattering (DLS), SEM, FTIR, static contact angle and water dispersion studies, and equilibrium binding experiments. They have proven to be nanoparticles (their diameters being around 104–397 nm, as determined by DLS in methanol) with surface‐grafted hydrophilic polymer brushes and exhibit excellent pure water‐compatible template binding properties. Moreover, obvious photoregulated template binding behaviors were observed for such azo‐containing MIP nanoparticles, which led to their largely accelerated template release in the aqueous media under the UV light irradiation. Furthermore, the general applicability of the strategy was also demonstrated. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1941–1952 相似文献
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The Bayesian model are established for the VaR and related risk measurements. The relationship between VaR and other risk measurements including expect shortfall, tail condition expectation and conditional value at risk are discussed. Furthermore, the Bayesian estimates and Bayesian predictors of these risk measurement are derived. Thirdly, the consistency and asymptotic normality in the exponential risk model are proved. Finally, the numerical simulation method is used to verify the convergence rate under different sample sizes. 相似文献
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Hongtao Yao Jianhua Zhou Hong Li Jiaojiao Zhao 《Journal of polymer science. Part A, Polymer chemistry》2019,57(12):1305-1314
A simple method for nanocrystalline cellulose (NCC)/fluorinated polyacrylate was developed by RAFT‐mediated surfactant‐free emulsion polymerization, in which the nanocomposites formed a core‐shell spherical morphology. The influence of the content of NCC‐g‐(PAA‐b‐PHFBA) (AA was acrylic acid, HFBA was hexafluorobutyl acrylate) on the properties of latex and film were systematically studied. The monomer conversion, the tensile strength, and water–oil repellency of film increased first and then decreased, the latex particle size decreased first and then decreased, when the content of NCC‐g‐(PAA‐b‐PHFBA) increased from 1 to 6 wt %. Elongation at break and thermal stability distinctly decreased when the content of NCC‐g‐(PAA‐b‐PHFBA) gradually increased. XPS showed that the fluorine‐containing groups well concentrated at the film–air interfaces during the annealing process. SEM analysis revealed that the treated fiber had a rugged surface, and the treated fabric had an excellent water repellency. In addition, this green grafting method in water offered a new perspective for the fabrication of exceptional NCC‐based nanocomposites with NCC as the core and also helped to promote the potential applicability of NCC in a range of multipurpose applications. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1305–1314 相似文献
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Ronghai Xu Xin Sensen Ni Qingzhao Zeng Hongtao Li Moucheng 《Russian Journal of Electrochemistry》2021,57(6):636-643
Russian Journal of Electrochemistry - The corrosion behavior of enamel coating on carbon steel was investigated in the tap water at 80°C (i.e., the simulated electric hot water tank... 相似文献
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