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101.
Fast, mass, and low‐cost production of high‐quality graphene, which is alluring, remains a great challenge, even though some approaches have shown potential for mass synthesis of graphene. Very recently a great breakthrough was made by Tour and co‐workers (Nature 2020, 577, 647–651): in just a second, easily exfoliated and highly crystalline graphene was produced from abundant carbon‐containing species by cost‐effective flash Joule heating with a low energy input of 7.2 kJ per gram graphene. Such an ultrafast, economic, and scalable process for high‐quality graphene production can be considered as a milestone in the graphene field and is highlighted in this article.  相似文献   
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Superwetting membranes with responsive properties have attracted heightened attention because of their fine‐tunable surface wettability. However, their functional diversity is severely limited by the “black‐or‐white” wettability transition. Herein, we describe a coating strategy to fabricate multifunctional responsive superwetting membranes with SiO2/octadecylamine patterns. The adjustable patterns in the responsive region are the key factor for functional diversity. Specifically, the coated part of the membrane displayed a superhydrophobicity/superhydrophilicity transition at different pH values, whereas the uncoated part exhibited invariant superhydrophilicity. On the basis of this anisotropy/isotropy transition, the membranes can serve as either responsive permeable membranes or signal‐expression membranes, thus enabling the responsive separation and permeation of liquids with satisfactory separation efficiency (>99.90 %) and flux (ca. 60 L m?2 h), as well as real‐time liquid signal expression with alterable signals.  相似文献   
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The reversible introduction of functionality at material surfaces is of interest for the development of functional biomaterials. In particular, the use of supramolecular immobilization strategies facilitates mild reaction and processing conditions, as compared to other covalent analogues. Here, the engineering of multicomponent supramolecular materials, beyond the use of a single supramolecular entity is proposed. Cucurbit[8]uril (Q8) mediated host–guest chemistry is combined with hydrogen bonding supramolecular 2‐ureido‐4‐pyrimidinone (UPy)‐based materials. The modular incorporation of a UPy‐additive that presents one guest to incorporate into the Q8 host allows for selective supramolecular functionalization at the water–polymer material interface. Supramolecular ternary complex formation at the material surface was studied by X‐ray photoelectron spectroscopy, which as a result of large overlap in atomic composition of the different components showed minor changes is surface composition upon complex formation. Surface MALDI‐ToF MS measurements revealed useful insights in the formation of complexes. Protein immobilization was monitored using both fluorescence spectroscopy and quartz crystal microbalance with dissipation monitoring, which successfully demonstrated ternary complex formation. Although proteins could selectively be immobilized onto the surfaces, control of the system's stability remains a challenge as a result of the dynamicity of the host–guest assembly. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3607–3616  相似文献   
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黎淑勤  刘信宏  邓阳 《化学教育》2022,43(12):92-98
以构建的科学本质要素框架作为分析工具,研究学生经科普微视频分析所呈现的科学本质观。结果表明,学生无法全面、深入分析视频呈现的科学本质,反映了局限的科学本质观,而经过讨论与汇报能在一定程度上提升其科学本质观。据此,为化学教育硕士研究生的培养工作提出3点建议,即将科普微视频作为科学本质教育的素材,促进学生形成完整且深刻的科学本质观,发展学生准确抽提课程资源中的科学本质的能力。  相似文献   
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The application of a variety of “surface‐science” techniques to elucidate surface structures and mechanisms of chemical reactions at zeolite surfaces has long been considered as almost impossible because of the poor electrical and thermal conductivity of those materials. Here, we show that the growth of a thin aluminosilicate film on a metal single crystal under controlled conditions results in adequate and well‐defined model systems for zeolite surfaces. In principle, silicate films that contain metals other than Al (e.g. Ti, Fe, etc) may be prepared in a similar way. We believe that this approach opens up a new playground for experimental and theoretical modeling of zeolites, aimed at a fundamental understanding of structure–reactivity relationships in such materials.  相似文献   
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A collection of excerpts from letters written by R. B. Woodward to his friends, colleagues, young students and others is presented. These excerpts are representative of Woodward 's lengthy correspondence and illustrate many aspects of his personality and philosophies of life.  相似文献   
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