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941.
Triphenylamine–Thienothiophene Organic Charge‐Transport Molecular Materials: Effect of Substitution Pattern on their Thermal,Photoelectrochemical, and Photovoltaic Properties 下载免费PDF全文
Thi Huong Le Dr. Quang‐Duy Dao Dr. Mai‐Phuong Nghiêm Prof. Sébastien Péralta Dr. Regis Guillot Prof. Quoc Nghi Pham Prof. Akihiko Fujii Prof. Masanori Ozaki Prof. Fabrice Goubard Prof. Thanh‐Tuân Bui 《化学:亚洲杂志》2018,13(10):1302-1311
Two readily accessible thienothiophene–triphenylamine charge‐transport materials have been synthesized by simply varying the substitution pattern of the triphenylamine groups on a central thienothiophene π‐linker. The impact of the substitution pattern on the thermal, photoelectrochemical, and photovoltaic properties of these materials was evaluated and, based on theoretical and experimental studies, we found that the isomer in which the triphenylamine groups were located at the 2,5‐positions of the thienothiophene core ( TT‐2,5‐TPA ) had better π‐conjugation than the 3,6‐isomer ( TT‐3,6‐TPA ). Whilst the thermal, morphological, and hydrophobic properties of the two materials were similar, their optoelectrochemical and photovoltaic properties were noticeably impacted. When applied as hole‐transport materials in hybrid perovskite solar cells, the 2,5‐isomer exhibited a power‐conversion efficiency of 13.6 %, much higher than that of its 3,6‐counterpart (0.7 %) under the same standard conditions. 相似文献
942.
Tien Doan Phan Thao My Trinh Thi Thu Khiem Le Hong Frontasyeva Marina Zinicovscaia Inga Son Nguyen An Van Dung Do 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(6):2743-2750
Journal of Radioanalytical and Nuclear Chemistry - Forty-five moss samples were collected at the end of the 2019 rainy season in Hanoi capital and some other cities in Red River Delta and the south... 相似文献
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944.
Thi Dao Phi Huong Doan Thi Mai Van Hieu Tran Van Loi Vu Bich Ngan Truong Tuan Anh Tran Van Minh Chau Van Cuong Pham 《Tetrahedron letters》2017,58(19):1830-1833
A series of bengamide E analogues were prepared from the corresponding polyketide chain and amino acids via amide coupling reactions. Opening of the polyketide chain lactone ring with α-aminolactams was successfully achieved under microwave irradiation in the presence of sodium 2-ethyl hexanoate. A cytotoxic activity evaluation against a panel of cancer cell lines (KB, HepG-2, Lu-1, MCF-7, HL-60 and Hela) indicated that the 2′R analogues were generally more cytotoxic than the 2′S analogues. Additionally, several analogues exhibited selective inhibition against various cancer cell lines: compounds 32a and 32b selectively inhibited MCF-7 cells, while 33b and 35b were more sensitive toward Lu-1 and HepG-2, respectively. Notably, some of the synthetic analogues possess cytotoxic activities with IC50 values less than 1 µM. 相似文献
945.
Dr. Nathan D. Kirchhofer Samantha R. McCuskey Dr. Cheng-Kang Mai Prof. Guillermo C. Bazan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6619-6622
We probe anaerobic respiration of bacteria in the presence of conjugated polyelectrolytes (CPEs). Three different CPEs were used to probe how structural variations impact biocurrent generation from Shewanella oneidensis MR-1. For the self-doped anionic CPE only, absorption spectroscopy shows that the addition of S. oneidensis MR-1 leads to the disappearance of the polaron (radical cation) band at >900 nm and an increase in the band at 735 nm due to the neutral species, consistent with electron transfer from microbe to polymer. Microbial three-electrode electrochemical cells (M3Cs) show an increase in the current generated by S. oneidensis MR-1 with addition of the self-doped CPE relative to other CPEs and controls. These experiments combined with in situ cyclic voltammetry suggest that the doped CPE facilitates electron transport to electrodes and reveal structure–function relationships relevant to developing materials for biotic/abiotic interfaces. 相似文献
946.
For geometric progressions with common ratios greater than 4, the speed of convergence to the uniform distribution is determined for almost all initial values. 相似文献
947.
Mudumala Veeranarayana Reddy Gangireddy Chandra Sekhar Reddy Nguyen Thi Kim Lien Dong Wook Kim Yeon Tae Jeong 《Tetrahedron》2017,73(10):1317-1323
A facile and efficient method for the synthesis of benzo[4,5]imidazo[1,2-a]pyrimidines has been achieved via highly active and reusable heterogeneous poly acrylic acid-supported layered double hydroxides (PAA-g-LDHs) catalyst promoted one-pot reaction of 1H-benzo[d]imidazol-2-amine, with α,β-unsaturated carbonyl compounds under solvent-free conditions. PAA-g-LDHs catalyst was successfully synthesized via reversible addition-fragmentation chain-transfer polymerization using grafting reaction and was characterized by different analytical techniques. The significant features of this reaction include expedient one-pot process, short reaction time, excellent yields, wide substrate scope and operational simplicity. Also, the catalyst could be reused for several consecutive runs without any apparent loss in its catalytic activity. 相似文献
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950.
Improving the Passivation Stability of a Polymer Thin Film on Si by the Introduction of MoO3 Nanoparticles Into the Polymer Matrix (Phys. Status Solidi RRL 9/2017) 下载免费PDF全文