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991.
Chen-Yuan Tu Ying-Ling Liu Min-Tzu Luo Kueir-Rarn Lee Juin-Yih Lai 《Chemphyschem》2006,7(6):1355-1360
Poly(glycidyl methacrylate), PGMA, chains in linear and arborescent structures were incorporated onto surfaces of poly(tetrafluoroethylene), PTFE, films by hydrogen plasma and ozone treatment and atom transfer radical polymerization. The epoxide groups of the PGMA chains were further reacted with acetic acid (AAc), oxalic acid (XAc), allyl amine (AA), and ethylenediamine (EDN) to introduce hydroxyl and amine groups to the surfaces of the PTFE films. Surface characterizations performed by Fourier Transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy and X-ray photoelectron spectroscopy (XPS) confirmed the surface modification and the chemical structure. The PGMA chains in arborescent structures show a high effectiveness for the enhancement of the adhesion of PTFE films. The adhesion of PTFE films was also significantly enhanced by ring-opening reactions of the PGMA epoxide groups with acetic acid and amine compounds. A high value of 9.5 N cm(-1) in the optimum 180 degrees peel strength test was observed with PTFE/copper assemblies. 相似文献
992.
本文研究究了Cr(NO3)3与四种浓度的反丁烯二酸共存时Cr3+在水溶液中的聚合状态,采用LEMIT程序计算了在四种配体浓度下存在的同一粒子(离子或分子),其水解常数不但彼此吻合,且和高、低浓度区的结果一致。 相似文献
993.
Xin-hua Wan Hui-lin Tu Ying-feng Tu Dong Zhang Ling Sun Qi-feng Zhou Yu-ping Dong Mao Tang Department of Polymer Science & Engineering College of Chemistry Peking University Beijing China Department of Materials & Chemical Engineering Beijing Institute of Technology Beijing China 《高分子科学》1999,(2):189-192
The first TEMPO-mediated "living" free radical polymerization of liquid crystallinemonomer, 2, 5-bis[(4-methoxyphenyl)oxycarbonyl]styrene(MPCS), was carried out at 130℃ withBPO as an initiator. The molecular weight of the polymer can be varied from rather low values to highvalues while maintaining narrow polydispersity. It was observed that the polymerization of MPCSproceeded much faster than that of styrene. A tentative explanation for this fast polymerization wassuggested. 相似文献
994.
Lowering Molecular Symmetry To Improve the Morphological Properties of the Hole‐Transport Layer for Stable Perovskite Solar Cells
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Dr. Xuchao Wang Jing Zhang Dr. Shuwen Yu Dr. Wei Yu Dr. Ping Fu Xuan Liu Dandan Tu Prof. Xin Guo Prof. Can Li 《Angewandte Chemie (International ed. in English)》2018,57(38):12529-12533
Inspired by the structural feature of the classical hole‐transport material (HTM), Spiro‐OMeTAD, many analogues based on a highly symmetrical spiro‐core were reported for perovskite solar cells (PSCs). However, these HTMs were prone to crystallize because of the high molecular symmetry, forming non‐uniform films, unfavorable for the device stability and large‐area processing. By lowering the symmetry of spiro‐core, we report herein a novel spirobisindane‐based HTM, Spiro‐I, which could form amorphous films with high uniformity and morphological stability. Compared to the Spiro‐OMeTAD‐based PSCs, those containing Spiro‐I exhibit similar efficiencies for small area but higher ones for large area (1 cm2), and especially much higher air stability (retaining 80 % of initial PCE after 2400 h storage without encapsulation). Moreover, the Spiro‐I can be synthesized from a cheap starting material bisphenol A and used with a small amount for the device fabrication. 相似文献
995.
We define Toeplitz operators on all Dirichlet spaces on the unit ball of
and develop their basic properties. We characterize bounded, compact, and Schatten-class Toeplitz operators with positive
symbols in terms of Carleson measures and Berezin transforms. Our results naturally extend those known for weighted Bergman
spaces, a special case applies to the Arveson space, and we recover the classical Hardy-space Toeplitz operators in a limiting
case; thus we unify the theory of Toeplitz operators on all these spaces. We apply our operators to a characterization of
bounded, compact, and Schatten-class weighted composition operators on weighted Bergman spaces of the ball. We lastly investigate
some connections between Toeplitz and shift operators.
The research of the second author is partially supported by a Fulbright grant. 相似文献
996.
Vu H.H. Nguyen Son H. Doan Tram T. Van Phuc H. Pham Tran T.N. Nguyen Ngoc N. Nguyen Thach N. Tu Nam T.S. Phan 《应用有机金属化学》2019,33(4)
Iron‐based metal–organic framework VNU‐20 was utilized as a heterogeneous catalyst for cascade reactions between ketoximes and dibenzyl ether to produce 2,4,6‐triphenylpyridines. Additionally, benzyl alcohol and (dimethoxymethyl)benzene could be used as an alternative starting materials for the transformation. The oxidant exhibited a remarkable impact on the reactions, and di‐tert‐butylperoxide was the most appropriate candidate. The VNU‐20 displayed higher efficiency than many homogeneous and heterogeneous catalysts. The catalyst was reusable for the cascade reactions without a noticeable deterioration in catalytic activity. This transformation is new, and would offer alternative routes to triphenylpyridines utilizing ketoximes as building blocks. 相似文献
997.
Tomasz Porba Michelle Ernst Dominik Zimmer Piero Macchi Nicola Casati 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(20):6697-6701
We report the high‐pressure structural characterization of an organic polyiodide salt in which a progressive addition of iodine to triiodide groups occurs. Compression leads to the initial formation of discrete heptaiodide units, followed by polymerization to a 3D anionic network. Although the structural changes appear to be continuous, the insulating salt becomes a semiconducting polymer above 10 GPa. The features of the pre‐reactive state and the polymerized state are revealed by analysis of the computed electron and energy densities. The unusually high electrical conductivity can be explained with the formation of new bonds. 相似文献
998.
Kerli Süleyman Alver Ümit Eskalen Hasan Uruş Serhan Soğuksu Ali Kemal 《Russian Journal of Applied Chemistry》2019,92(2):304-309
Russian Journal of Applied Chemistry - Boron doped vanadium thin films were fabricated on the micro-slide glass substrates by spray pyrolysis technique at substrate temperature of 400°C.... 相似文献
999.
Russian Journal of Electrochemistry - A voltammetric sensor for the determination of bisphenol S (BPS) in aqueous samples was fabricated by immobilization of β-cyclodextrin/multiwalled carbon... 相似文献