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排序方式: 共有208条查询结果,搜索用时 171 毫秒
31.
A series of poly(ethylene glycol)(PEG)-4,4′-diphenylmethanediisocyanate(MDI)-poly(dimethylsiloxane) (PDMS) multiblock copolymers were synthesized by employing two-step growth polymerization technique. Atomic force microscopy (AFM) observed nanoscopically well-organized phase-separated surfaces consisting of hydrophilic domain from PEG and MDI segments and hydrophobic domain from PDMS segments even with 50 wt.% PDMS in the copolymer, and the multiblock copolymer coatings presented a surface free energy of as low as 6-8 mN m−1. 相似文献
32.
采用温和的反应条件,制备出三明治结构rGO/Fe_3O_4@mSiO_2,利用SEM、TEM、FTIR、XRD和N_2吸附-脱附等对其形貌和性能进行表征,考查了其对Hela细胞的毒性和细胞荧光成像效果,并探讨了其形成机理。实验结果表明:rGO/Fe_3O_4@mSiO_2具有较高的比表面积(217 m~2·g~(-1)),对抗癌药物五氟尿嘧啶(5-FU)的载药率达到57.34%;它还具有较好的磁性,磁饱和强度为32 emu·g-1;而且rGO/Fe_3O_4@mSiO_2纳米复合物在光照条件下具有优异的光热转换性能,对He La细胞表现出明显的杀伤效果。 相似文献
33.
We have systematically studied the reactions of acetalization and found that high reaction efficiency can be achieved using cheap and readily available organic Eosin Y as catalyst. The reaction proceeds smoothly under house bulbs and shows excellent functional group tolerance. The substrates of the reaction system are compatible with aromatic aldehydes, aliphatic aldehydes, aromatic ketones, and cyclic ketones with high yields. 相似文献
34.
《Polyhedron》2005,24(16-17):2625-2631
4,4′-Biimidazole derivatives having alkyl-substituents at 2- and 2′-positions were synthesized as new component molecules of supramolecular assemblies based on hydrogen-bonding interaction. The crystal structure analyses of methyl and ethyl derivatives revealed intriguing three-dimensional structures constructed by hydrogen-bonded networks. Furthermore, the methyl derivative formed a six-membered cyclic motif of hydrogen-bonded network to build up a channel structure. The ethyl derivative gave the two polymorphous, anhydrate and dihydrate, depending on conditions of the crystallization. The anhydrate constructed three-dimensional hydrogen-bonded networks by direct N–H⋯N hydrogen-bondings. In the crystal structure of the dihydrate of ethyl derivative, three-dimensional hydrogen-bonding interaction through water molecules formed a channel structure. 相似文献
35.
Zhou Quan Qian Le Pan Qianqian Si Guanqing Qi Zhaopeng Zheng Yuchuan Li Changjiang 《Research on Chemical Intermediates》2020,46(1):533-545
Research on Chemical Intermediates - In this paper, a novel chemosensor (named L1) for Fe3+ based on the rhodamine 6G and o-vanillin has been synthesized, which can selectively recognize Fe3+. The... 相似文献
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Yuanqing Wei Ting Liu Binru Zheng Yilin Song Shengsong Wang Mojuan Zheng Yanling Xu Yumei Chi Ming Zhao Jin-ao Duan Shuying Han Rui Liu 《Journal of separation science》2022,45(4):812-823
A new strategy combined gold-coated magnetic nanocomposites assisted enrichment with mass spectrometry was developed for the characterization of disulfide bond-contained proteins from Chinese cobra (Naja atra) venom. In this work, core-shell nanocomposites were synthesized by the seed-mediated growth method and used for the enrichment of snake venom proteins containing disulfide bonds. A total of 3545 tryptic digested peptides derived from 96 venom proteins in Naja atra venom were identified. The venom proteins comprised 14 toxin families including three-finger toxins, phospholipase A2, snake venom metalloproteinase, cobra venom factor, and so forth. Extra 16 venom proteins were detected exclusively in the nanocomposites set, among which 11 venom proteins were from the three-finger toxins family. In the present study, the proposed simple and efficient protocol replaced the tedious and laborious technologies commonly used for pre-separating crude snake venom, suggesting widely implementation in low-abundance or trace disulfide bond-contained proteins or peptides characterization. 相似文献
38.
Heping Jiang Wei Jiang 《Annals of Differential Equations》2010,(1):24-29
Based on the stability theory of functional differential equations, this paper studies the asymptotic stability of a singular system with distributed delays by constructing suitable Lyapunov functionals and applying the linear matrix inequalities. A numerical example is given to show the effectiveness of the main results. 相似文献
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