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991.
Xiaolan Tong Shan Wang Jun Zuo Yingchong Ge Qiang Gao Suijun Liu Jianhua Ding Fen Liu Jianqiang Luo Jianbo Xiong 《中国化学快报》2021,32(2):604-608
Two new hydrostable two-dimensional(2 D) uranyl coordination complexes [(UO_2)_5(μ_3-O)_2(nbca)_2].7 H_2O(1) and [(UO_2)_3(nbca)_2(H_2O)_3]·2 H_2O(2)(H_3 nbca=5-nitro-1,2,3-benzenetricarboxylic acid) were hydrothermal synthesized.Single-crystal structural refinements reveal that both of the two complexes were formed by the packing of 2D uranyl coordination sheets via the hydrogen bonds.The nbca ligand coordinating to the uranyl polyhedron centers constructed the 2D sheets.There are UO_8 hexagonal bipyramids and UO_7 pentagonal bipyramids in 1 while only U07 pentagonal bipyramids in 2.Photocatalytic degradation of rhodamine B(RhB) in aqueous solution was studied.Complex 2 possesses better performance than 1 with 96.2 % of the RhB was degraded in only 60 min.Mechanism studies reveal that the dissolved oxygens are essential to the RhB degradation.The photocurrent density of 2 is more stable than that of 1,which indicating the stronger ability to separate photoexcited electrons and hole pairs of 2. 相似文献
992.
Three new emitters,namely 10,10'-(quinoline-2,8-diyl)bis(10 H-phenoxazine)(Fene),10,10'-(quinoline-2,8-diyl)bis(10 H-phenothiazine)(Fens) and 10,10'-(quinoline-2,8-diyl)bis(9,9-dimethyl-9,10-dihydroacridine)(Yad),featuring quinoline as a new electron acceptor have been designed and conveniently synthesized.These emitters possessed small singlet-triplet splitting energy(ΔEst) and twisted structures,which not only endowed them show thermally activated delayed fluorescence(TADF)properties but also afforded a remarkable aggregation-induced emission(AIE) feature.Moreover,they also showed aggregation-induced delayed fluorescence(AIDF) property and good photoluminescence(PL) property,which are the ideal emitters for non-doped organic light-emitting diodes(OLEDs).Furthermore,high-performance non-doped OLEDs based on Fene,Fens and Yad were achieved,and excelle nt maximum external quantum efficiencies(EQE_(max)) of 14,9%,13.1% and 17,4%,respectively,were obtained.It was also found that all devices exhibited relatively low turn-on voltages ranging from 3.0 V to3.2 V probably due to their twisted conformation and the AIDF properties.These results demonstrated the quinoline-based emitters could have a promising application in non-doped OLEDs. 相似文献
993.
Disclosed herein is an efficient Ag-catalyzed 4+1 heteroannulation reaction of enamides with α-carbonyl sulfoxonium ylides.The diastereoselective transformation provides a practical access to a diverse range of multi-functionalized oxazoline derivatives.The synthetic utility of the resultant tetrasubstituted oxazolines is further demonstrated by a series of useful manipulations into valuable building blocks of pharmaceutical relevance. 相似文献
994.
Liu-Qiao Zhang Yang Gao Zhi-Hao Huang Wei Zhang Nian-Chen Zhou Zheng-Biao Zhang Xiu-Lin Zhu 《高分子科学》2021,39(1):60-69
The controlled and efficient synthesis of polymers with tailored topologies is challenging but important for exploring structure/property research. Herein, we proposed a concept of macro-latent monomer to achieve the controlled growth of polymer topologies.The macro-latent monomer was installed by a dynamic furan/maleimide covalent bond at the chain terminal. One-shot reversible additionfragmentation chain transfer(RAFT) polymerization of styrene and the macro-latent monomer created controlled growth of polymer topologies.Low temperature such as 40 ℃ could not activate the macro-latent monomer and thus the polymerization created the homo-polystyrene. By contrast, high temperature of ~110 ℃ activated the macro-latent monomer, and a maleimide-terminated macro-monomer was released via the retro-Diels Alder reaction. This macro-monomer immediately joined the cross polymerization with styrene and thus produced the side chains. By delicately manipulating the polymerization temperature, the predetermined placement of the macro-latent monomer-derived polymeric sidechains created controllably growing topologies, including star-, π-shaped, and density-variable grafting copolymers. This work paved a new way for creating on-demand topologies and would greatly enrich the topology synthesis. 相似文献
995.
996.
997.
Xiao Fuchuan Gao Jie Huang Xuanting Hu Qingjian Li Ran Zhang Xinxiang 《Cellulose (London, England)》2021,28(9):5463-5475
Cellulose - Poly(methylhydrogen)siloxane (PMHS) was applied for hydrophobic modification of bamboo flour (BF) at room temperature based on the dehydrogenation between hydroxyl groups of BF and... 相似文献
998.
Gao Bingbing Yang Jiahui Zhang Shuidong Li Xiangyu 《Cellulose (London, England)》2021,28(13):8405-8418
Cellulose - High performance fibers and improved interfacial interaction can enhance the properties of polymer composites. Herein, microcrystalline cellulose (MCC) was oxidized by H2O2/CuSO4, a new... 相似文献
999.
1000.
Hou Yu-Ting Wu Fan Yao Jian-Hua Zhu Zhou-Hai Mi Qi-Li Gao Qian Zhou Min Ye Yan-Qing Wang Wei-Guang Yang Guang-Yu Hu Qiu-Fen Guan Ying 《Chemistry of Natural Compounds》2021,57(5):864-868
Chemistry of Natural Compounds - Two new isobenzofuranone derivatives (1 and 2) together with six known compounds (3–8) were isolated from the roots of Phlomis betonicoides, a highly sweet... 相似文献