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921.
Chunyu Qiu Suqi He Dr. Yuan Wang Prof. Qingxiang Wang Prof. Chuan Zhao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(18):4120-4127
Interface engineering has been applied as an effective strategy to boost the electrocatalytic performance because of the strong coupling and synergistic effects between individual components. Here, we engineered vertically aligned FeOOH/CoO nanoneedle array with a synergistic interface between FeOOH and CoO on Ni foam (NF) by a simple impregnation method. The synthesized FeOOH/CoO exhibits outstanding electrocatalytic activity and stability for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in an alkaline medium. For the overall water splitting, the bifunctional FeOOH/CoO nanoneedle catalyst requires only a cell voltage of 1.58 V to achieve a current density of 10 mA cm−2, which is much lower than that required for IrO2//Pt/C (1.68 V). The FeOOH/CoO catalyst has been successfully applied for solar cell-driven water electrolysis, revealing its great potential for commercial hydrogen production and solar energy storage. 相似文献
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Yang Li Ruchun Chen Yiyang Li Kaniyarakkal Sharafudeen Shijian Liu Dakun Wu Yiling Wu Xixi Qin Jianrong Qiu 《Mikrochimica acta》2015,182(9-10):1827-1834
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Shi Qiu Wen-zhi Yang Xiao-jian Shi Chang-liang YaoMin Yang Xuan LiuBao-hong Jiang Wan-ying Wu De-an Guo 《Analytica chimica acta》2015
Exploration of new natural compounds is of vital significance for drug discovery and development. The conventional approaches by systematic phytochemical isolation are low-efficiency and consume masses of organic solvent. This study presents an integrated strategy that combines offline comprehensive two-dimensional liquid chromatography, hybrid linear ion-trap/Orbitrap mass spectrometry, and NMR analysis (2D LC/LTQ-Orbitrap-MS/NMR), aimed to establish a green protocol for the efficient discovery of new natural molecules. A comprehensive chemical analysis of the total ginsenosides of stems and leaves of Panax ginseng (SLP), a cardiovascular disease medicine, was performed following this strategy. An offline 2D LC system was constructed with an orthogonality of 0.79 and a practical peak capacity of 11,000. The much greener UHPLC separation and LTQ-Orbitrap-MS detection by data-dependent high-energy C-trap dissociation (HCD)/dynamic exclusion were employed for separation and characterization of ginsenosides from thirteen fractionated SLP samples. Consequently, a total of 646 ginsenosides were characterized, and 427 have not been isolated from the genus of Panax L. The ginsenosides identified from SLP exhibited distinct sapogenin diversity and molecular isomerism. NMR analysis was finally employed to verify and offer complementary structural information to MS-oriented characterization. The established 2D LC/LTQ-Orbitrap-MS/NMR approach outperforms the conventional approaches in respect of significantly improved efficiency, much less use of drug materials and organic solvent. The integrated strategy enables a deep investigation on the therapeutic basis of an herbal medicine, and facilitates new compounds discovery in an efficient and environmentally friendly manner as well. 相似文献
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Huidan Zeng Yuxia Yang Xiongwei Jiang Guorong Chen Jianrong Qiu Fuxi Gan 《Journal of Crystal Growth》2005,280(3-4):516-520
We report the space selective precipitation of Pd nanoparticles in Pd2+-doped silicate glass by ultrashort laser pulses irradiation and further annealing. Absorption spectra, transmission electron microscopy, refractive index measurement and Z-scan technique demonstrated that metallic Pd nanoparticles were precipitated in the glass sample after irradiation by an 800-nm femtosecond laser and subsequent annealing at 600 °C. We discuss a refractive index change and nonlinear absorption that combines the precipitation of Pd nanoparticles. 相似文献