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161.
Chung J. Lee 《高分子科学杂志,C辑:聚合物评论》2013,53(4):431-560
Abstract Since polyimides were invented more than 30 years ago, several books dealing with the subject have been published [33, 34, 40u, 48b, 55, 64]. While some of these books [33–35] have very thorough and systematic coverage of the chemistry and general physical, mechanical, and electrical properties of polyimides, most of the literature [40, 48b, 64] is made up of collections of results derived from application-related research on various polyimides. None of the earlier treatises is totally devoted to an understanding of the underlying principles involved in just a single, important property such as the glass transition temperatures of polyimides. 相似文献
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Hailing Liu Hoyong Chung 《Journal of polymer science. Part A, Polymer chemistry》2017,55(21):3515-3528
Lignin is an important source of synthetic materials because of its abundance in nature, low cost, stable supply, and no competition to the human food supply. Lignin, a cross‐linked phenolic polymer, contains a large number of aromatic groups that can be used as a substitute for petroleum‐based aromatic fine chemicals. However, modification of lignin is necessary for its application in advanced materials due to its chemically inert nature and structural complexity. Polymeric modification of lignin via graft copolymerization represents an important avenue for modification because this method forms stable covalent bond linkages between lignin and synthetic functional polymers. In this review, we discuss recent synthetic strategies toward polymeric modification of lignin using graft copolymerization and the special properties and applications of the produced lignin copolymers. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3515–3528 相似文献
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In several recent investigations dealing with the economic order quantity with permissible delay in payments, the following assumptions are made: 相似文献
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Wai Chung Fu Zheng Wang Dr. Wesley Ting Kwok Chan Prof. Dr. Zhenyang Lin Prof. Dr. Fuk Yee Kwong 《Angewandte Chemie (International ed. in English)》2017,56(25):7166-7170
A versatile π-extension reaction was developed based on the three-component cross-coupling of aryl halides, 2-haloarylcarboxylic acids, and norbornadiene. The transformation is driven by the direction and subsequent decarboxylation of the carboxyl group, while norbornadiene serves as an ortho-C−H activator and ethylene synthon via a retro-Diels–Alder reaction. Comprehensive DFT calculations were performed to account for the catalytic intermediates. 相似文献
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Soo Chung Christian M. Jennings Prof. Jeong-Yeol Yoon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(57):13070-13077
In recent years, there has been high interest in paper-based microfluidic sensors or microfluidic paper-based analytical devices (μPADs) towards low-cost, portable, and easy-to-use sensing for chemical and biological targets. μPAD allows spontaneous liquid flow without any external or internal pumping, as well as an innate filtration capability. Although both optical (colorimetric and fluorescent) and electrochemical detection have been demonstrated on μPADs, several limitations still remain, such as the need for additional equipment, vulnerability to ambient lighting perturbation, and inferior sensitivity. Herein, alternative detection methods on μPADs are reviewed to resolve these issues, including relatively well studied distance-based measurements and the newer capillary flow dynamics-based method. Detection principles, assay performance, strengths, and weaknesses are explained for these methods, along with their potential future applications towards point-of-care medical diagnostics and other field-based applications. 相似文献
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Chung Liao Feng 《Journal of Electrostatics》2013,71(3):551-553
In the literature there are reports of static charges appearing with physical (i.e., phase and temperature) changes of water. One of the purposes of the present report is to refine the measurement of charge in heated water. The experiments described in this report confirm the reported phenomenon by comparing the different amounts of charge produced when different amounts of water are heated to the same temperature and in the same setup. When charge differential is correlated to water differential, the source of charge is better isolated to the change in water temperature rather than to any other possible source. 相似文献