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1.
Nowadays, oil pollution has become more serious, which causes great threats both to the ecological environment and human life. In this study, a novel type of multifunctional deacetylated cellulose acetate/polyurethane (d-MCA:MTPU) composite nanofiber membranes for oil/water separation are successfully fabricated by electrospinning, which show super-amphiphilicity in air, super-hydrophilicity in oil, and oleophobicity in water. All the d-MCA:MTPU composite nanofiber membranes with different mass ratios can be used as water-removing, oil-removing, and emulsion separation substance only by gravity driving force. The highest separation flux for water and oil reaches up to 37 000 and 74 000 L m−2 h−1, respectively, and all the separation efficiencies are more than 99%. They have outstanding comprehensive mechanics performance, which can be controlled by simply adjusting the mass ratios. They show excellent antifouling and self-cleaning ability, endowing powerful cyclic stability and reusability. Those results show that d-MCA:MTPU composite nanofiber membranes have great application prospects in oil/water separation. 相似文献
2.
Xiaozhen Li Chao Yin Si Si Liew Chun-Sing Lee Kanyi Pu 《Advanced functional materials》2021,31(46):2106154
Optical imaging has played a pivotal role in deciphering in vivo bioinformatics but is limited by shallow penetration depth and poor imaging performance owing to interfering tissue autofluorescence induced by concurrent photoexcitation. The emergence of near-infrared (NIR) self-luminescence imaging independent of real-time irradiation has timely addressed these problems. There are two main kinds of self-luminescent agents, namely inorganic and organic luminophores. Inorganic luminophores usually suffer from long-term biotoxicity concerns resulting from potential heavy-metal ions leakage and nonbiodegradability, which hinders their further translational application. In contrast, organic luminophores, especially organic semiconducting luminophores (OSLs) with good biodegradable potential, tunable design, and outstanding optical properties, are preferred in biological applications. This review summarizes the recent progress of OSLs used in NIR afterglow, chemiluminescence, and bioluminescence imaging. Molecular manipulation and nanoengineering approaches of OSLs are discussed, with emphasis on strategies that can extend the emission wavelength from visible to NIR range and amplify luminescence signals. This review concludes with a discussion of current challenges and possible solutions of OSLs in the self-luminescence field. 相似文献
3.
Scientometrics - Governments typically formulate sets of policies to guide the direction of scientific research. And the possible effects of these policies on scientific research have been... 相似文献
4.
Yazhi Liu Shuofeng Liang Chenrui Yuan Andreas Best Michael Kappl Kaloian Koynov Hans-Jürgen Butt Si Wu 《Advanced functional materials》2021,31(37):2103908
Anticounterfeiting materials are used to distinguish real banknotes, products, and documents from counterfeits, fakes, or unauthorized replicas. However, conventional anticounterfeiting materials generally exhibit a single anticounterfeiting function, resulting in a low level of security. Herein, a novel anticounterfeiting nanocomposite is demonstrated with numerous prominent security features. The nanocomposite is fabricated by doping upconverting nanoparticles (UCNPs) in a photoresponsive azobenzene-containing polymer (azopolymer). Because of the cis–trans photoisomerization of the azopolymer, the nanocomposite exhibits photoinduced reversible color changes suitable for anticounterfeiting applications. Additionally, the hard nanocomposite can be converted to a rubber-like soft solid by light irradiation. Imprinted microstructures are fabricated on the photosoftened nanocomposite, which result in photonic colors. Moreover, polarization-dependent structures are fabricated on the nanocomposite via photoinduced orientation for encryption. Importantly, UCNPs in the nanocomposite emit visible light upon excitation by near-infrared light, enabling the observation of various anticounterfeiting structures with high contrast. An advantage of the anticounterfeiting nanocomposite is that the security features can be observed by the naked eye for quick discrimination and can be analyzed using laboratory equipment for higher accuracy. The anticounterfeiting nanocomposite is easily processed on paper, glass, and plastic, which demonstrates its potential anticounterfeiting functions for banknotes, wines, and medicines. 相似文献
5.
Chen Jianxin Deng Hongmei Zheng Dongliang Pan Yanlin Si Shufang Zhang Yuemin Yang Pingxiong Chu Junhao 《Journal of Materials Science: Materials in Electronics》2021,32(8):10151-10159
Journal of Materials Science: Materials in Electronics - The composite materials in the form of (1-x)BaTiO3-xSrFe0.5Nb0.5O3((1-x)BT-xSFN) are synthesized via the solid-state reaction route.... 相似文献
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Sudong Chae Seungbae Oh Kyung Hwan Choi Jin Woong Lee Jiho Jeon Zhixiang Liu Cong Wang Chaeheon Woo Liyi Shi Joohoon Kang Si Young Song Sung Jae Kim Jung Heon Lee Hak Ki Yu Jae-Young Choi 《Ceramics International》2021,47(9):11935-11941
To achieve the stable dispersion of 1D van der Waals crystal Mo6S3I6 in aqueous media, the tri-block copolymer (Poloxamer) is used as dispersant. The head group of Poloxamer, hydrophobic polypropylene oxide parts can be adsorbed to Mo6S3I6 surface by hydrophobic interaction and the tail group with hydrophilic polyethylene oxide exposed to the outside of the Mo6S3I6 is soluble in water and can form sufficient steric hindrance, resulting in stable aqueous dispersion in nm scale. The excellent biocompatibility of aqueous dispersed nm scale 1D Mo6S3I6 was demonstrated by effective proliferation of C2C12 cells. 相似文献
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International Journal of Control, Automation and Systems - This paper studies the leader-following consensus for a class of nonlinear singular multi-agent systems. Unlike the related works, the... 相似文献
10.
This paper focuses on the unconditional stability and convergence of characteristics type methods for the time-dependent incompressible MHD equations. For this purpose, we introduce a new characteristics time-discrete system. The optimal error estimates in and norms for the typical modified characteristics finite element method unconditionally can be deduced, while the whole previous works require certain time-step restrictions. Some numerical experiments document performance of the characteristics type methods for the time-dependent incompressible MHD equations. 相似文献