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41.
V. Percec J. Heck G. Johansson D. Tomazos M. Kawasumi G. Ungar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(8):1031-1070
Abstract The first part of this paper discusses the molecular design of selected examples of structural units containing taper-shaped exo-receptors and various crown ether, oligooxyethylenic, and H-bonding-based endo-receptors, which self-assemble into cylindrical channel-like architectures via principles resembling those of tobacco mosaic virus. The ability of these structural units to self-assemble via a delicate combination of exo-and endo-recognition processes will be presented. A comparison between various supramolecular (generated via H-bonding, ionic, and electrostatic interactions) and molecular “polymer backbones” will be made. The present limitations concerning the ability to engineer the structural parameters of these supramolecular channel-like architectures and some possible novel material functions derived from them will be briefly mentioned. The second part of this paper discusses our research on the molecular design of a novel class of macrocyclics which self-assemble via intramolecular recognition processes into supramolecular “rodlike” collapsed macrocyclics which display thermotropic liquid crystalline mesophases. It is demonstrated that these macrocyclics have a higher ability to form liquid crystalline phases than the corresponding linear compounds which have identical or even higher degrees of polymerization. Therefore, they represent the ideal molecular architectures which generate mesophases. 相似文献
42.
Dr. Masahiro Hayakawa Mayu Kameda Ryosuke Kawasumi Dr. Soichiro Nakatsuka Dr. Nobuhiro Yasuda Prof. Dr. Takuji Hatakeyama 《Angewandte Chemie (International ed. in English)》2023,62(14):e202217512
Organic light-emitting diodes (OLEDs) receive considerable attention because of their commercial use in flat panel displays. Herein, highly efficient spiroborate-based host materials are reported for use in blue OLEDs. Our designed spiroborates ( SBOX ) were simple to synthesize and exhibited high triplet excitation energies, narrow S-T gaps, and balanced charge carrier mobilities. A blue OLED containing one of the designed spiroborates, SBON , as a host exhibited a high external quantum efficiency (27.6 %) and low turn-on voltage (3.7 V) compared to those observed using 3,3′-di(9H-carbazol-9-yl)-1,1′-biphenyl (17.6 % and 4.5 V, respectively), indicating their potential as host materials in OLEDs. 相似文献
43.
We give necessary and sufficient conditions for the boundedness of generalized fractional integral and maximal operators on Orlicz–Morrey and weak Orlicz–Morrey spaces. To do this, we prove the weak–weak type modular inequality of the Hardy–Littlewood maximal operator with respect to the Young function. Orlicz–Morrey spaces contain spaces (), Orlicz spaces, and generalized Morrey spaces as special cases. Hence, we get necessary and sufficient conditions on these function spaces as corollaries. 相似文献