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排序方式: 共有204条查询结果,搜索用时 15 毫秒
191.
Ze LIU Li Xiang WANG* Xia Bin JING Fo Song WANG The State Key Laboratory of Polymer Physics Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 《中国化学快报》2002,13(3)
For making the polymer light-emitting diode (PLED) device with good performance, it is desirable to reach the balance of electron and hole injection. However, for most conjugated polymer, hole injection is more favorable than electron injection. So it is important to design and synthesize the bipolar conjugated polymer with both electron and hole transporting ability for the fabrication of single-layer PLED1-2. In this communication we present the synthesis and preliminary characterizatio… 相似文献
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193.
Tingjunhong Ni Lei Pang Zhan Cai Fei Xie Zichao Ding Yumeng Hao Ran Li Shichong Yu Xiaoyun Chai Ting Wang Yongsheng Jin Dazhi Zhang Yuanying Jiang 《Journal of Saudi Chemical Society》2019,23(5):576-585
In order to explore novel antifungal agents, twenty-seven triazole derivatives featuring an alkyne linker in the side chain were designed and synthesized by the Sonogashira reaction. Most of the target compounds exhibited good antifungal activity against eight human pathogenic fungi, especially excellent activity against Candida and Cryptococcus species, comparing with the reference drugs fluconazole, voriconazole and ravuconazole. Compounds A2 and A3 exhibited in vitro activity against all the tested fungi with MIC80 values ranging from 0.0156 μg/mL to 0.5 μg/mL, which are superior to ravuconazole and fluconazole. SAR and molecular docking study give a clear conclusion that para-fluoro, para-chloro, and para-cyano substituted phenylalkynyl or pyridinylalkynyl side chains may promote triazole antifungal activity. 相似文献
194.
Fengchi Wu Gang Ou Ye Wang Haizhe Zhong Lifu Zhang Henan Li Yumeng Shi 《化学:亚洲杂志》2019,14(16):2796-2801
Urea is an important organic pollutants in sewage and needs to be removed for environmental protection. Here, we report defective NiFe2O4 (NFO) nanoparticles with excellent performance for urea electro‐oxidation. The results show that defects can be effectively implanted at the surface of NFO nanoparticles by a facile and versatile lithium reduction method without affecting its main crystal structure and grain size. The defective NFO‐5Li nanoparticles displayed a significantly improved urea electro‐oxidation performance compared with NFO‐Pristine nanoparticles. Particularly, the NFO‐Pristine and NFO‐5Li show a potential of 1.398 and 1.361 V at the current density of 10 mA cm?2 and Tafel slope of 37.3 and 31.4 mV dec?1, respectively. In addition, the NFO‐5Li nanoparticles also revealed outstanding electrocatalytic stability. The superior performance can be attributed to the designed tunable surface defect engineering. Furthermore, the defect engineering strategy as well as the defective NFO nanoparticles hold great potential for applications in other materials and areas. 相似文献
195.
Miaomiao Wu Yumeng Xue Na Li Hongyang Zhao Bo Lei Min Wang Jianwei Wang Meng Luo Chao Zhang Yaping Du Chunhua Yan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(21):6954-6959
The development of biodegradable inorganic nanoparticles with a tumor microenvironment‐activated therapeutic mode of action is urgently needed for precision cancer medicine. Herein, the synthesis of ultrathin lanthanide nanoscrolls (Gd2O3 NSs) is reported, which biodegrade upon encountering the tumor microenvironment. The Gd2O3 NSs showed highly controlled magnetic properties, which enabled their high‐resolution magnetic resonance imaging (MRI). Importantly, Gd2O3 NSs degrade in a pH‐responsive manner and selectively penetrate tumor tissue, enabling the targeted release of anti‐cancer drugs. Gd2O3 NSs can be efficiently loaded with an anti‐cancer drug (DOX, 80 %) and significantly inhibit tumor growth with negligible cellular and tissue toxicity both in vitro and in vivo. This study may provide a novel strategy to design tumor microenvironment‐responsive inorganic nanomaterials for biocompatible bioimaging and biodegradation‐enhanced cancer therapy. 相似文献
196.
Yumeng Xue Zengjie Zhang Wen Niu Mi Chen Min Wang Yi Guo Cong Mao Cai Lin Bo Lei 《Particle & Particle Systems Characterization》2019,36(4)
Monodispersed bioactive glass nanoparticles (BGNs) have received much attention in various biomedical applications such as tissue regeneration, drug/gene delivery, bioimaging, and cancer therapy. However, the poor dispersion stability of BGNs in a physiological environment has limited their wide biomedical applications. The long‐term in vitro/in vivo toxicity and biodegradation of BGNs are also not clear. Monodispersed glycerolphosphate‐functionalized BGNs (GP‐BGN) are synthesized and their stability under physiological environment in vitro, and long‐term biodegradation behavior in vitro and in vivo are investigated herein. GP‐BGN shows significantly enhanced particles stability in physiological environment, good hemocompatibility and cellular biocompatibility, as well as high cellular uptake ability. GP‐BGN also exhibits long‐term biodegradation behavior in vitro/in vivo and negligible biotoxicity (tissue and blood toxicity). This study demonstrates that monodispersed surface‐functionalized BGNs could be used as biocompatible and biodegradable nanomaterials for long‐term safe bioimaging and disease therapy. 相似文献
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198.
Qun He Dr. Daobin Liu Dr. Ji Hoon Lee Yumeng Liu Dr. Zhenhua Xie Dr. Sooyeon Hwang Prof. Dr. Shyam Kattel Prof. Dr. Li Song Prof. Dr. Jingguang G. Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(8):3057-3061
The electrochemical CO2 reduction reaction (CO2RR) to yield synthesis gas (syngas, CO and H2) has been considered as a promising method to realize the net reduction in CO2 emission. However, it is challenging to balance the CO2RR activity and the CO/H2 ratio. To address this issue, nitrogen-doped carbon supported single-atom catalysts are designed as electrocatalysts to produce syngas from CO2RR. While Co and Ni single-atom catalysts are selective in producing H2 and CO, respectively, electrocatalysts containing both Co and Ni show a high syngas evolution (total current >74 mA cm−2) with CO/H2 ratios (0.23–2.26) that are suitable for typical downstream thermochemical reactions. Density functional theory calculations provide insights into the key intermediates on Co and Ni single-atom configurations for the H2 and CO evolution. The results present a useful case on how non-precious transition metal species can maintain high CO2RR activity with tunable CO/H2 ratios. 相似文献
199.
Methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME) are oxygenated compounds added to gasoline to enhance octane rating and to improve combustion. They may be found as pollutants of living and working environments. In this work a robotized method for the quantification of low level MTBE, ETBE and TAME in human urine was developed and validated. The analytes were sampled in the headspace of urine by SPME in the presence of MTBE-d12 as internal standard. Different fibers were compared for their linearity and extraction efficiency: carboxen/polydimethylsiloxane, polydimethylsiloxane/divinylbenzene, and polydimethylsiloxane. The first, although highly efficient, was discarded due to deviation of linearity for competitive displacement, and the polydimethylsiloxane/divinylbenzene fiber was chosen instead. The analysis was performed by GC/MS operating in the electron impact mode. The method is very specific, with range of linearity 30-4600 ng L−1, within- and between-run precision, as coefficient of variation, <22 and <16%, accuracy within 20% the theoretical level, and limit of detection of 6 ng L−1 for all the analytes. The influence of the matrix on the quantification of these ethers was evaluated analysing the specimens of seven traffic policemen exposed to autovehicular emissions: using the calibration curve and the method of standard additions comparable levels of MTBE (68-528 ng L−1), ETBE (<6 ng L−1), and TAME (<6 ng L−1) were obtained. 相似文献
200.