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131.
Separation, analysis and recycling technologies are of high interest for our modern societies, where colloidal iron and aluminium (hydr)oxides have important applications. However, there are significant gaps in the fundamental understanding of how these phases form in real systems. Classical nucleation theory cannot account for many experimental observations, and there is a dichotomy between the chemistry of hydrolysing/condensating systems and the physical notion of supersaturation. Reviewing parts of the established and recent literature, we demonstrate that concepts of nonclassical nucleation pathways can overcome these issues. This broader, chemistry-based conceptual framework has a high potential for advancing current applications, and developing new strategies towards separation, analysis and recycling applications, which seem to be urgently required for the future. 相似文献
132.
Kathryn A. Dooley Annalisa Chieli Aldo Romani Stijn Legrand Costanza Miliani Koen Janssens John K. Delaney 《Angewandte Chemie (International ed. in English)》2020,59(15):6046-6053
Vincent van Gogh used fugitive red lake pigments that have faded in some paintings. Mapping their distribution is key to understanding how his paintings have changed with time. While red lake pigments can be identified from microsamples, in situ identification and mapping remain challenging. This paper explores the ability of molecular fluorescence imaging spectroscopy to identify and, more importantly, map residual non‐degraded red lakes. The high sensitivity of this method enabled identification of the emission spectra of eosin (tetrabromine fluorescein) lake mixed with lead or zinc white at lower concentrations than elemental X‐ray fluorescence (XRF) spectroscopy used on account of bromine. The molecular fluorescence mapping of residual eosin and two carmine red lakes in van Gogh's The Olive Orchard is demonstrated and compared with XRF imaging spectroscopy. The red lakes are consistent with the composition of paint tubes known to have been used by van Gogh. 相似文献
133.
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
134.
Ruixiang Qu Xiangyu Li Yanan Liu Huajun Zhai Shuaiheng Zhao Lin Feng Yen Wei 《Angewandte Chemie (International ed. in English)》2020,59(32):13437-13443
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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136.
Qingchun Li 《高等学校计算数学学报(英文版)》2007,16(4):341-347
In this paper,a compound-type inclusion interval of basic coneigenvalues of(com- plex)matrix is obtained.The corresponding boundary theorem and isolating theorem are given. 相似文献
137.
138.
基于彩色扫描仪的图像光谱重构 总被引:5,自引:0,他引:5
针对彩色扫描仪的特点,采用主元分析法(PCA)和反向传播(BP)人工神经网络(ANN)相结合的方法对图像光谱重构进行研究。选择IT8.7/2标准色卡作为训练样本,将该色卡中的另一组色靶作为检验样本以讨论不同网络结构以及不同主元数和训练样本数对光谱重构的影响,再以自然色系统(NCS)色卡为检验样本来分析不同种类的训练和检验样本与光谱重构性能的关系。实验结果表明,采用3-14-6网络结构和6个主元数是最佳选择,训练样本和扫描目标之间的一致性是基于彩色扫描仪图像光谱重构的关键所在。 相似文献
139.
140.
对近十年来化学计量学在生命科学领域相关研究中的应用进行了综述,主要对其在DNA、蛋白质及氨基酸这三大生命物质有关研究中的使用展开了评述和讨论,参考文献59篇。 相似文献