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排序方式: 共有4158条查询结果,搜索用时 156 毫秒
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Dr. Yukun Zhu Chunxiao Lv Zhuocheng Yin Prof. Jun Ren Prof. Xianfeng Yang Prof. Chung-Li Dong Prof. Hongwei Liu Dr. Rongsheng Cai Yu-Cheng Huang Prof. Wolfgang Theis Prof. Shaohua Shen Prof. Dongjiang Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(2):878-883
Red phosphorus is a promising photocatalyst with wide visible-light absorption up to 700 nm, but the fast charge recombination limits its photocatalytic hydrogen evolution reaction (HER) activity. Now, [001]-oriented Hittorf's phosphorus (HP) nanorods were successfully grown on polymeric carbon nitride (PCN) by a chemical vapor deposition strategy. Compared with the bare PCN and HP, the optimized PCN@HP hybrid exhibited a significantly enhanced photocatalytic activity, with HER rates reaching 33.2 and 17.5 μmol h−1 from pure water under simulated solar light and visible light irradiation, respectively. It was theoretically and experimentally indicated that the strong electronic coupling between PCN and [001]-oriented HP nanorods gave rise to the enhanced visible light absorption and the greatly accelerated photoinduced electron–hole separation and transfer, which benefited the photocatalytic HER performance. 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(13):3620-3623
Redox reactions are central to energy conversion and life metabolism. Herein we present electrochemical measurements with fluorescent readout of the redox‐sensitive dye Methylene Blue (MB), at the single‐molecule (SM) level. To overcome the low fluorescence quantum yield of MB we enhanced fluorescence by using individual gold nanorods to achieve the required sensitivity. By measuring the same molecule at different electrochemical potentials we determined the mid‐point potential of each single molecule through its redox‐induced fluorescence blinking dynamics. 相似文献
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APPLICATION OF WAVELET TRANSFORM TO BIFURCATION AND CHAOS STUDY 总被引:2,自引:0,他引:2
I.IntroductionThetypesofmotionforanonlinearvibrationsystemmaybeperiodic,quasiperiodicorchaotic.Foragivensetofparametersofthesystem,Poincarkmap,powerspectral,waveformandLyapunovexponentareusuallyutilizedtoseewhethertheresponseofthesystemischaoticornot,butitisdiftlculttodeterminepreciselytheexistingdomainsorattractingbasinsofdifferenttypesofmotionsinparametricspaceorinitialvaluespaceonlyfromgraphicsstudy,andcomputingLyapunovexponentistimeconsuming.Aswavelettransformcanreveallocalpropertyinboth… 相似文献
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M. Saka T. Shoji H. Takahashi H. Abé 《Journal of the mechanics and physics of solids》1982,30(4):209-224
A finite element analysis was performed to simulate crack tip blunting and the development of the intense strain region in a small compact tension specimen (0.4 T CT) of SA533B-1 under plane strain large-scale yielding, with the condition of large-geometry change around the crack tip taken into consideration. The region where the equivalent plastic strain g3p is greater than 0.15 was defined as the intense strain region, which corresponded to the recrystallized-etched zone delineated experimentally around the blunting crack tip. The development of the intense strain region was discussed as a function of the J-integral and the crack opening displacement. A linear relationship was obtained between the plastic work Wp dissipated within the intense strain region and (J/σy)2 or b2, where b is the crack opening displacement, defined as the separation of the two points at which the boundary of the intense strain region surrounding the crack tip intersects with the free surfaces of the crack. 相似文献
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Junpeng Xie Xiaodan Li Haojie Lai Zhijuan Zhao Jinliang Li Wanggang Zhang Weiguang Xie Yiming Liu Wenjie Mai 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(41):14882-14889
Metal–organic framework‐derived NiCo2.5S4 microrods wrapped in reduced graphene oxide (NCS@RGO) were synthesized for potassium‐ion storage. Upon coordination with organic potassium salts, NCS@RGO exhibits an ultrahigh initial reversible specific capacity (602 mAh g?1 at 50 mA g?1) and ultralong cycle life (a reversible specific capacity of 495 mAh g?1 at 200 mA g?1 after 1 900 cycles over 314 days). Furthermore, the battery demonstrates a high initial Coulombic efficiency of 78 %, outperforming most sulfides reported previously. Advanced ex situ characterization techniques, including atomic force microscopy, were used for evaluation and the results indicate that the organic potassium salt‐containing electrolyte helps to form thin and robust solid electrolyte interphase layers, which reduce the formation of byproducts during the potassiation–depotassiation process and enhance the mechanical stability of electrodes. The excellent conductivity of the RGO in the composites, and the robust interface between the electrodes and electrolytes, imbue the electrode with useful properties; including, ultrafast potassium‐ion storage with a reversible specific capacity of 402 mAh g?1 even at 2 A g?1. 相似文献
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SiC和石墨混杂增强铜基复合材料的高温摩擦磨损特性研究 总被引:5,自引:1,他引:5
采用MMU-5G型端面摩擦磨损试验机研究了SiC和石墨颗粒混杂增强铜基复合材料在250~400 ℃与GCr15钢对摩时的高温摩擦磨损特性,并与SiC/Cu复合材料进行对比分析.结果表明:加入石墨颗粒可以降低复合材料和偶件GCr15钢的磨损率,获得低而稳定的摩擦系数;同时,有效防止高温条件下严重粘着转移现象的发生,使得在400 ℃下混杂复合材料仍具有较低的磨损率.这是由于在混杂增强铜基复合材料的高温磨损表面上通过"磨屑机械混合→热压"的机制形成了连续的富石墨机械混合层,而对磨损表面起到良好的固体润滑作用,使得SiC和石墨混杂增强铜基复合材料具有良好的高温摩擦磨损特性. 相似文献