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Huai-Ling Gao Ran Zhao Chen Cui Yin-Bo Zhu Si-Ming Chen Zhao Pan Yu-Feng Meng Shao-Meng Wen Chuang Liu Heng-An Wu Shu-Hong Yu 《国家科学评论(英文版)》2020,7(1):73
Bio-sourced nanocellulosic materials are promising candidates for spinning high-performance sustainable macrofibers for advanced applications. Various strategies have been pursued to gain nanocellulose-based macrofibers with improved strength. However, nearly all of them have been achieved at the expense of their elongation and toughness. Inspired by the widely existed hierarchical helical and nanocomposite structural features in biosynthesized fibers exhibiting exceptional combinations of strength and toughness, we report a design strategy to make nanocellulose-based macrofibers with similar characteristics. By combining a facile wet-spinning process with a subsequent multiple wet-twisting procedure, we successfully obtain biomimetic hierarchical helical nanocomposite macrofibers based on bacterial cellulose nanofibers, realizing impressive improvement in their tensile strength, elongation and toughness simultaneously. The achievement certifies the validity of the bioinspired hierarchical helical and nanocomposite structural design proposed here. This bioinspired design strategy provides a potential platform for further optimizing or creating many more strong and tough nanocomposite fiber materials for diverse applications. 相似文献
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在流动相组成为正己烷/异丙醇(80/20,v/v),温度为291K-313K条件下,考察了2种结构相似的外消旋硒代甘油醚色谱手性拆分的热力学行为。计算了两种对映体与固定相相互作用的焓变以及焓变差值和熵变差值等热力学参数。手性色谱柱填料为自制的纤维素-三(3,5-二甲基苯基氨基甲酸酯)手性固定相。 相似文献
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文章介绍了几种纤维素类手性拆分剂以及其制备方法相关分离机理,综述了纤维素手性拆分剂的分离机理及其应用,重点地介绍纤维素手性固定相和纤维素膜的应用。 相似文献
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纤维素schiff碱是一种环保的纤维素衍生物,在很多行业具有很大的发展潜力。文章简述了纤维素schiff碱结构、性质及应用。 相似文献
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纤维素作为世界上最丰富的可再生资源,将纤维素功能化是人们研究的热点之一,文章综述了纤维素智能化的设计原理、纤维素智能材料的种类、智能化研究进展。 相似文献
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多环芳烃(PAHs)是中国土壤中广泛存在的一类具有致癌、致畸、致突变等危害的持久性有机污染物,其在环境中降解缓慢,具有生物累积性,并可通过食物链传递、放大,对人体健康构成很大威胁,因此迫切需要开展其生物有效性及生态风险相关研究. 本文研究了农田污染土壤中14种中到高疏水性PAHs在植物体内的吸收、累积及从根部向茎叶部分的传输. 结果表明中到高疏水性的有机污染物如PAHs可在植物体内发生从根向茎叶的传输,向茎叶传输的量与化合物的疏水性之间存在显著的线性定量关系;同时,一种新型半渗透膜采样装置--三油酸甘油酯-醋酸纤维素复合膜(TECAM)被成功地应用于土壤中PAHs的采集及其对植物(Triticum aestivum L.)和蚯蚓(Eisenia andrei)的生物有效性,结果表明:TECAM对土壤中PAHs的采样可在48h内达到表观平衡,大大缩短了土壤中有机污染物的采样时间;TECAM可反映PAHs在土壤中的残留时间、土壤有机质及溶解有机碳含量对PAHs生物有效性的影响;TECAM内PAHs浓度与蚯蚓体内浓度存在显著的线性相关关系;与化学提取方法相比,TECAM采集的PAHs不仅在浓度上与小麦根中浓度存在显著线性相关关系,而且TECAM采集的PAHs量也与小麦根富集的量相当;进一步提出了"土壤-孔隙水-TECAM"三室模型,并成功地描述了TECAM采集土壤中PAHs的三相平衡过程;此外,TECAM采样对土壤扰动小,操作简单,因此是采集土壤中有机污染物以及评价土壤中有机污染物生物有效性的有效方法. 相似文献
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Qing-Fang Guan Zi-Meng Han Tong-Tong Luo Huai-Bin Yang Hai-Wei Liang Si-Ming Chen Guang-Sheng Wang Shu-Hong Yu 《国家科学评论(英文版)》2019,6(1):64
Although a variety of nanoparticles with better-than-bulk material performances can be synthesized, it remains a challenge to scale the extraordinary properties of individual nanoscale units to the macroscopic level for bulk nanostructured materials. Here, we report a general and scalable biosynthesis strategy that involves simultaneous growth of cellulose nanofibrils through microbial fermentation and co-deposition of various kinds of nanoscale building blocks (NBBs) through aerosol feeding on solid culture substrates. We employ this biosynthesis strategy to assemble a wide range of NBBs into cellulose nanofibril-based bulk nanocomposites. In particular, the biosynthesized carbon nanotubes/bacterial cellulose nanocomposites that consist of integrated 3D cellulose nanofibril networks simultaneously achieve an extremely high mechanical strength and electrical conductivity, and thus exhibit outstanding performance as high-strength lightweight electromagnetic interference shielding materials. The biosynthesis approach represents a general and efficient strategy for large-scale production of functional bulk nanocomposites with enhanced performances for practical applications. Industrial-scale production of these bulk nanocomposite materials for practical applications can be expected in the near future. 相似文献