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191.
192.
Two-dimensional covalent organic framework(COF) has distinctive properties that offer potential opportunities for developing advanced electrode materials.In this work,a core-shell material composed of TAPB-DMTP-COF(TAPB,1,3,5-tris(4-aminophenyl)benzene;DMTP,2,5-dimethoxyterephaldehyde)core and conducting polymer shell,TAPB-DMTP-COF@PANI,was synthesized solvothermally using a polymerization method.The structural cha racteristics of the prepared composite were revealed by X-ray diffraction patterns(XRD),fourier transform infrared spectra(FTIR),X-ray photoelectron spectroscopy(XPS),transmission electron microscopy(TEM).The electrochemical analyses were verified by subsequent monitoring of trace levels of acetaminophen.This resultant composite not only facilitated acetaminophen to interact with absorption sites by π-π stacking effect and hydrogen bonding but also overcame the poor conductivity of COF.Under the optimal conditions,a low limit of detection of0.032 μmol/L and wide linear range of 0.10-500 μmol/L were obtained.The electrochemical platform was almost unaffected by other interfering substances,and successfully applied for the practical detection of acetaminophen in commercial tablet,human blood serum and urine.The enhanced performance makes this COF based core-shell composite a promising material in electrochemical senso r. 相似文献
193.
S-Monofluoromethyl phosphorothioates represent an important class of organofluorine compounds and are re ported here for the first time.A series of S-monofluoromethyl phosphorothioates are conveniently synthesized from different PⅤ-H compounds and PhSO2SCH2F under mild conditions.The method is compatible with common functional groups and provides potential opportunities to synthesize new bioactive molecules for medicinal chemistry. 相似文献
194.
This review is mainly focused on the optoelectronic properties of diamond-based one-dimensional-metal-oxide heterojunction. First, we briefly introduce the research progress on one-dimensional (1D)-metal-oxide heterojunctions and the features of the p-type boron-doped diamond (BDD) film; then, we discuss the use of three oxide types (ZnO, TiO2 and WO3) in diamond-based-1D-metal-oxide heterojunctions, including fabrication, epitaxial growth, photocatalytic properties, electrical transport behavior and negative differential resistance behavior, especially at higher temperatures. Finally, we discuss the challenges and future trends in this research area. The discussed results of about 10 years’ research on high-performance diamond-based heterojunctions will contribute to the further development of photoelectric nano-devices for high-temperature and high-power applications. 相似文献
195.
196.
Dr. Qicai Xiao Dr. Wei Du Dr. Xiao Dong Dr. Shubo Du Sing Yee Ong Dr. Guanghui Tang Dr. Changyu Zhang Dr. Fen Yang Prof. Dr. Lin Li Prof. Dr. Liqian Gao Prof. Dr. Shao Q. Yao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(47):12207-12214
Mitochondria are key organelles that perform vital cellular functions such as those related to cell survival and death. The targeted delivery of different types of cargos to mitochondria is a well-established strategy to study mitochondrial biology and diseases. Of the various existing mitochondrion-transporting vehicles, most suffer from poor cytosolic entry, low delivery efficiency, limited cargo types, and cumbersome preparation protocols, and none was known to be universally applicable for mitochondrial delivery of different types of cargos (small molecules, proteins, and nanomaterials). Herein, two new cell-penetrating, mitochondrion-targeting ligands (named MitoLigand) that are capable of effectively “tagging” small-molecule drugs, native proteins and nanomaterials are disclosed, as well as their corresponding chemoselective conjugation chemistry. Upon successful cellular delivery and rapid endosome escape, the released native cargos were found to be predominantly localized inside mitochondria. Finally, by successfully delivering doxorubicin, a well-known anticancer drug, to the mitochondria of HeLa cells, we showed that the released drug possessed potent cell cytotoxicity, disrupted the mitochondrial membrane potential and finally led to apoptosis. Our strategy thus paves the way for future mitochondrion-targeted therapy with a variety of biologically active agents. 相似文献
197.
Zhao Tianqi Luo Tianzi Fang Bo Shi Lijiang Jin Yongxing Zhou Pengwei Yao Dong Li Chenxia Jing Xufeng Hong Zhi 《Journal of Russian Laser Research》2021,42(5):586-597
Journal of Russian Laser Research - The zero-refractive-index metamaterials have excellent electromagnetic properties, which provide new ideas and methods to realize the control of electromagnetic... 相似文献
198.
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
199.
Liu Changqi Huo Dongying Yang Xu Ma Zhanwen Zhou Jianjin Han Chao Bai Xiaohou Wu Kang Zhang Yu Wang Junrun Yao Zeen Wei Zheng 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):1091-1099
Journal of Radioanalytical and Nuclear Chemistry - A Frisch-grid Ionization Chamber (FGIC) for the measurement of low activity of alpha-particle emitters has been built. The design and performance... 相似文献
200.
交通事故的时空热点分析 总被引:1,自引:0,他引:1
针对目前交通事故分析中时空维度分离的不足,以H市2013―2015年的交通事故数据为研究对象,根据自组织神经网络、平行坐标系、时空颜色矩阵和时空网络核密度估计、热点分析法,分别从行政区划以及道路网络上进行交通事故的时空特征分析,从宏观和微观角度揭示交通事故的时空热点区域。结果表明,整体来说,在空间上,H市交通事故热点区域4个街道高于8个镇,呈明显的“两带一中心”分布,即硖许线与101省道形成的带状区域和市政府所在的行政中心区域;时间上,早、晚高峰时段最为严重,夜晚较为轻微,呈明显的区域特征分布,即工业办公区热点出现在早高峰时段,生活住宅区热点出现在晚高峰时段,商业消费区热点出现在夜晚时段。 相似文献