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排序方式: 共有117条查询结果,搜索用时 31 毫秒
61.
通过两步法制备了一种空心六边形镍钴硫化物(HHNCS)与还原氧化石墨烯(RGO)的纳米复合材料HHNCS/RGO。利用XRD,SEM,TEM和Raman光谱等对复合物进行表征,发现镍钴硫化物为空心六边形结构,并且均匀地附着在RGO的表面。该纳米复合物用作超级电容器电极表现出优异的电化学性能。在电流密度为1 A·g-1时比电容为927 F·g-1;当电流密度增大到20 A·g-1时,比电容仍高达724 F·g-1,表明材料拥有较好的倍率性能。此外,在电流密度5 A·g-1下循环2000次后比电容保留有初始值的93%,显示出优异的循环稳定性。HHNCS/RGO优异的电容性能主要是由于RGO的存在不仅增强了材料的导电性,而且作为理想的载体分散HHNCS纳米片。HHNCS/RGO纳米复合物优异的电化学性能使其在超级电容器电极材料领域具有应用前景。 相似文献
62.
Xiao-Xia Liu Shi-Qing Sun Yu-Jie Wang Wei Xu Yi-Fang Wang Daeui Park Hai-Meng Zhou Hong-Yan Han 《Applied biochemistry and biotechnology》2013,169(1):145-158
A combination of enzymatic inhibition kinetics and computational prediction was employed to search for an effective inhibitor of tyrosinase. We found that oxymatrine significantly inhibited tyrosinase, and that this reaction was not accompanied by detectable conformational changes. Kinetic analysis showed that oxymatrine reversibly inhibited tyrosinase in a mixed-type manner. Measurements of intrinsic and ANS-binding fluorescences showed that oxymatrine did not induce any conspicuous changes in the tertiary structure. We also conducted a docking simulation between tyrosinase and oxymatrine using two docking programs, Dock6.3 and AutoDock4.2 (binding energy was ?118.81 kcal/mol for Dock6 and ?8.04 kcal/mol for AutoDock4). The results also suggested that oxymatrine interacts mostly with the residues of CYS83 and HIS263 in the active site of tyrosinase. This strategy of predicting tyrosinase inhibition by simulation of docking coupling with kinetics may prove useful in screening for potential tyrosinase inhibitors. Knowledge of tyrosinase inhibition can provide medical, cosmetic, and agricultural applications. Our study suggests that oxymatrine is an important agent for various applications related to pigment formation. 相似文献
63.
Junqi Tang Qihua Zhang Chongyi Zeng Shi-Qing Man 《Applied Physics A: Materials Science & Processing》2013,111(4):1099-1105
Ag films on tinning glass substrates were fabricated by modified silver-mirror (Tollen’s) reaction with the advantage of low-cost, simple and quick fabrication process. The obtained Ag films were served as sacrificial materials for preparation of Ag/Au nanocomposite films by immersing in a chlorauric acid (HAuCl4) solution at room temperature. After a short time of galvanic replacement reaction, Ag/Au bimetallic nanostructures were synthesized with “concave” structures. The morphology, properties and composition of the Ag and Ag/Au nanocomposite films were analyzed by using scanning electron microscopy (SEM), UV-visible spectroscopy, X-ray diffraction (XRD), energy-dispersive X-ray spectrometry (EDS) and surface enhanced Raman scattering (SERS). SEM images displayed that the large area of Ag film and Ag/Au bimetallic nanostructures experienced structural evolution process during galvanic reaction. The UV-Vis spectra showed the absorbencies characterization of Ag film and Ag/Au nanocomposite films. SERS measurements using methylene blue as an analyte showed that SERS intensities of bimetallic films were enhanced significantly compared with that of pure Ag films. The SERS enhancement ability of Ag/Au bimetallic films was dependent on the immersion time for galvanic replacement reaction. 相似文献
64.
65.
Spin pumping at the Co2FeAlo.sSio.5/Pt and Pt/Co2FeAIo.sSio.5 interfaces has been studied by ferromagnetic res- onance technology (FMR). The spin mixing conductance of the Co, FeA~o.sSio.s/Pt and Pt/Co2FeAlo.sSio.5 interfaces was determined to be 3.7~ lO19 m-2 and 2.1 ~ lO19 m 2 by comparing the Gilbert damping in a Co2FeAIo.sSio.5 sin- gle film, Co2FeAlo.sSio.s/Pt bilayer film and a Pt/Co2FeAIo.sSio.s/Pt trilayer film. Spin pumping is more efficient in the Co2FeAlosSios/Pt bilayer film than in permalloy/Pt bilayer film. 相似文献
66.
67.
We have carried out uniaxial extension experiments on a monodisperse entangled melt to illustrate the origin of failure in the glass-like zone defined by Malkin and Petrie (J Rheol 41:1–25, 1997). The entangled melt was found to undergo a yield-to-rupture transition beyond a critical rate. We show that the onset of the “glass-like” zone defined by Malkin and Petrie is actually in the middle of the rubbery plateau where the mechanical response of entangled melts is not dictated by glassy chain dynamics. The rupture occurs plausibly through chain scission in the limit of finite chain extensibility. 相似文献
68.
杨仕清 《原子与分子物理学报》2017,34(2):192-194
正1前言今年4月14日是我们最崇敬的导师、我国著名物理学家和教育家芶清泉先生诞辰100周年纪念日.我从1987年考入芶先生所创建的成都科技大学高温高压与原子分子物理科学所硕士研究生以来,至今已达30周年.芶先生亲自给我们研究生讲授量子力学2(也就是量子矩阵力学)、原子结构的变分计算及有幸多次聆听芶先生重要学术讲座.我1990年攻读博士学位期间,他亲自指导我从事 相似文献
69.
The hexagonal born nitride based yellow afterglow phosphor was prepared by the rapid combustion method and its luminescent properties were characterized. The phosphor prepared at 800 ℃ for 30 min is with excellent luminescent performance. After irradiation by UV light, the yellow long-lasting phosphorescence can be observed for above 2 h in the limit of light perception of dark-adapted human eyes(0.32 mcd·m-2). 相似文献
70.