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121.
Dr. Ke Li Dr. Jian Yang Prof. Rong Huang Prof. Shaoliang Lin Prof. Jinlou Gu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(33):14228-14232
Ordered mesoporous metal–organic frameworks (mesoMOFs) were constructed with a uniform pore size up to about 10 nm and thick microporous walls, opening up the possibility for the mass diffusion of large-size molecules through crystalline MOFs. The synergistic effects based on triblock copolymer templates and the Hofmeister salting-in anions promote the nucleation of stable MOFs in aqueous phase and the in situ crystallization of MOFs around templates, rendering the generation of a microcrystal with periodically arranged large mesopores. The improved mass transfer benefiting from large-pore channels, together with robust microporous crystalline structure, endows them as an ideal nanoreactor for the highly efficient digestion of various biogenic proteins. This strategy could set a guideline for the rational design of new ordered large-pore mesoMOFs with a variety of compositions and functionalities and pave a way for their potential applications with biomacromolecules. 相似文献
122.
以对苯二胺和对苯二甲醛为原料缩合制备出对苯二胺缩对苯二甲醛席夫碱聚合物(PT),研究了采用不同物质的量之比的单体所制备的聚合物的电化学性能。利用席夫碱聚合物中N原子上的孤对电子与不同金属离子配位形成席夫碱配位聚合物(PT-M),并对所形成聚合物的电化学性能进行了研究。采用X射线衍射(XRD)、红外(IR)、热重-差示扫描量热法(TG-DSC)、扫描电子显微镜(SEM)和能谱(EDS)对产物进行了表征,PT-M的XRD峰强度相比于PT明显降低,表明金属离子配位进入分子链骨架中引起的空间位阻减少了分子链排列的有序性。采用循环伏安、恒电流充放电和交流阻抗评价了所制备的配位聚合物材料的电化学性能。研究发现,聚席夫碱铝配合物(PT-Al)表现出较优的电化学性能,在0.5 A·g-1的电流密度下其电容值为649.6 F·g-1,并且具有较好的循环稳定性,在8 A·g-1的电流密度下循环1 000次后仍有80.9%的电容保持率。 相似文献
123.
作为一类典型软物质材料,近年来分子凝胶在生物医学、柔性电子设备、晶体控制生长、水体净化,以及3D打印材料、微纳米材料和高能量密度材料制备等领域表现出巨大的应用潜力,受到人们越来越多的关注。如何提高分子凝胶结构调控效率,拓展分子凝胶功能,促进分子凝胶实际应用已经成为新阶段分子凝胶研究的主要内容。本文结合本课题组的研究工作,从动态共价键调控分子凝胶力学性能、分子凝胶促进高品质有机晶体制备和高性能多孔高分子材料的分子凝胶(凝胶乳液)软膜板制备三个方面阐述分子凝胶的结构调控和功能化应用研究。在此基础上,简要展望分子凝胶研究的发展趋势。 相似文献
124.
质子交换膜(PEM)是质子交换膜燃料电池的核心组件之一,具有隔绝阴阳极、提供质子传递通道和阻止燃料渗透的作用. 商业化应用的全氟磺酸PEM存在燃料渗透严重、高温条件下导电性差和成本高的问题,开发性能优良的聚合物PEM显得很有必要. 本文讨论了近年来聚合物PEM的研究进展,分别从聚合物的主链、支链和交联结构角度介绍了分子结构对薄膜相分离、质子导电性、稳定性和电池性能等性能的影响,并讨论了聚合物分子结构设计方面存在的问题,最后对燃料电池用聚合物PEM在未来的发展方向进行了展望. 相似文献
125.
Diego Romano Perinelli Giovanni Filippo Palmieri Marco Cespi Giulia Bonacucina 《Molecules (Basel, Switzerland)》2020,25(24)
Flavours and fragrances are volatile compounds of large interest for different applications. Due to their high tendency of evaporation and, in most cases, poor chemical stability, these compounds need to be encapsulated for handling and industrial processing. Encapsulation, indeed, resulted in being effective at overcoming the main concerns related to volatile compound manipulation, and several industrial products contain flavours and fragrances in an encapsulated form for the final usage of customers. Although several organic or inorganic materials have been investigated for the production of coated micro- or nanosystems intended for the encapsulation of fragrances and flavours, polymeric coating, leading to the formation of micro- or nanocapsules with a core-shell architecture, as well as a molecular inclusion complexation with cyclodextrins, are still the most used. The present review aims to summarise the recent literature about the encapsulation of fragrances and flavours into polymeric micro- or nanocapsules or inclusion complexes with cyclodextrins, with a focus on methods for micro/nanoencapsulation and applications in the different technological fields, including the textile, cosmetic, food and paper industries. 相似文献
126.
This study aimed to produce nanoparticles of poly (acrylonitrile‐co‐itaconic acid) (P (AN‐co‐IA)) containing conjugated polymers of pyrrole, N‐Methylpyrrole, 2,5‐dimethylpyrrole, and 1‐(Triisopropylsilyl)pyrrole which were synthesized by emulsion polymerization. Nanocomposite structures of P (AN‐co‐IA)/polypyrrole and polymer of pyrrole derivatives were produced via in situ polymerization, and the nanoparticle formation were followed by morphologic and ultraviolet‐visible (UV‐Vis) spectroscopic methods. Characterizations were made by Fourier transform infrared‐attenuated total reflectance (FTIR‐ATR) and Raman spectroscopy. Atomic force microscopy (AFM) was used for investigating the surface characteristics of the nanoparticles. Characterization results revealed that nanoparticles containing conjugated polymers had rougher surface than P (AN‐co‐IA) nanoparticles. It was also observed that the nanoparticles were well‐distributed although having some agglomerates. Moreover, depending on the type of monomer of conjugated polymer, the shape and size of the produced nanoparticles differed by conjunction with their polymerization rate. These findings can be used as a startup information for production of carbon nanofibers (CNFs) with desired properties after oxidation and carbonization, and as a high‐performance and cost‐effective flame and heat‐resistant material (oxidized copolymers of polyacrylonitrile nanofiber). 相似文献
127.
《Journal of Saudi Chemical Society》2020,24(2):186-215
With the advancement in tissue engineering, researchers are working hard on new techniques to fabricate more advanced scaffolds from biocompatible polymers with enhanced porosity, appropriate mechanical strength, diverse shapes and sizes for potential applications in biomedical field in general and tissue engineering in particular. These techniques include electrospinning, solution blow spinning, centrifugal spinning, particulate leaching (salt leaching), freeze-drying, lithography, self-assembly, phase separation, gas foaming, melt molding, 3-D printing, fiber mesh and solvent casting. In this article we have summarized the scaffold’s fabrication techniques from biocompatible polymers that are reported so far, the recent advances in these techniques, characterization of the physicochemical properties of scaffolds and their potential applications in the biomedical field and tissue engineering. The article will help both newcomers and experts working in the biomedical implant fabrication to not only find their desired information in one document but also understand the fabrication techniques and the parameters that control the success of biocompatible polymeric scaffolds. Furthermore, a static analysis of the work published in all forms on the most innovative techniques is also presented. The data is taken from Scopus, restricting the search to biomedical fields and tissue engineering. 相似文献
128.
Pengfei Xia Shaowen Cao Bicheng Zhu Mingjin Liu Miusi Shi Jiaguo Yu Yufeng Zhang 《Angewandte Chemie (International ed. in English)》2020,59(13):5218-5225
Constructing heterojunctions between two semiconductors with matched band structure is an effective strategy to acquire high‐efficiency photocatalysts. The S‐scheme heterojunction system has shown great potential in facilitating separation and transfer of photogenerated carriers, as well as acquiring strong photoredox ability. Herein, a 0D/2D S‐Scheme heterojunction material involving CeO2 quantum dots and polymeric carbon nitride (CeO2/PCN) is designed and constructed by in situ wet chemistry with subsequent heat treatment. This S‐scheme heterojunction material shows high‐efficiency photocatalytic sterilization rate (88.1 %) towards Staphylococcus aureus (S. aureus) under visible‐light irradiation (λ≥420 nm), which is 2.7 and 8.2 times that of pure CeO2 (32.2 %) and PCN (10.7 %), respectively. Strong evidence of S‐scheme charge transfer path is verified by theoretical calculations, in situ irradiated X‐ray photoelectron spectroscopy, and electron paramagnetic resonance. 相似文献
129.
130.
Kaikai Wen Lifen Wu Xiaoxi Wu Ying Lu Tao Duan Han Ma Aidong Peng Qinqin Shi Hui Huang 《Angewandte Chemie (International ed. in English)》2020,59(31):12756-12761
Cancer possesses normoxic and hypoxia microenvironments with different levels of oxygen, needing different efficacies of photothermal and photodynamic therapies. It is important to precisely tune the photothermal and photodynamic effects of phototherapy nano‐agents for efficient cancer treatment. Now, a series of copolymeric nanoparticles (PPy‐Te NPs) were synthesized in situ by controlled oxidative copolymerization with different ratios of pyrrole to tellurophene by FeCl3. The photothermal and photodynamic effects of semiconducting nano‐agents under the first near‐infrared (NIR) irradiation were precisely and systematically tuned upon simply varying the molar ratio of the pyrrole to tellurophene. The PPy‐Te NPs were used for cancer treatment in mice, exhibiting excellent biocompatibility and therapeutic effect. This work presents a simple method to tune photothermal and photodynamic therapies effect in semiconducting nano‐agents for cancer treatment. 相似文献