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151.
Fabrication of large-scale ripples on fluorine-doped tin oxide films by femtosecond laser irradiation
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The large-scale uniform self-organized ripples are fabricated on fluorine-doped tin oxide (FTO) coated glass by femtosecond laser. They can be smoothly linked in a horizontal line with the moving of XYZ stage by setting its velocity and the repetition rate of the laser. The ripple-to-ripple linking can also be realized through line-by-line scanning on a vertical level. The mechanism analysis shows that the seeding effect plays a key role in the linking of ripples. 相似文献
152.
Lijie Zhu Minghan Zhang Xiuying Liu He Liu Yutang He Bo Wang Tao Ma 《Chemical Papers》2017,71(3):653-660
Soyasaponins were shown to have a wide range of biological activities in previous studies; however, the activities of their monomeric compounds are unclear. The aim of this study was to evaluate the in vitro antioxidant activities of soyasaponins in HepG2 cells. Four soyasaponins were isolated from soy hypocotyls and identified as soyasaponin Aa, Ab, Ba, and Bb. The protective effects of these soyasaponins against production of hydrogen peroxide-induced reactive oxygen species in cells were investigated. The cellular antioxidant activity of soyasaponins was found to be in a dose-dependent manner at concentrations ranging between 25 and 400 μg/mL in 24 h. Finally, based on cell morphology observations, group A soyasaponins showed better cellular antioxidant activity and anti-oxidative enzyme activity than group B ones, with an optimal concentration of 100 μg/mL. 相似文献
153.
Xue-Yang Jiang Xin-Chen Li Wen-Yuan Liu Yun-Hui Xu Feng Feng Wei Qu 《Tetrahedron》2017,73(14):1895-1903
Hydrolyzing flavonoid glucuronides into corresponding aglycones posed some significant challenges. To improve acid-catalyzed hydrolysis process of flavonoid glucuronide, structures of glucuronide, hydrolysis parameters and post-processing were optimized. The optimized condition was performed by hydrolysis flavonoid glycoside methyl ester in a mixed solvent consisting of 2 mol/L H2SO4/EtOH/H2O (1/8/1, v/v/v) at 95 °C for 7 h and resulted in up to 90% aglycone yields, minimal byproduct formations and milder hydrolysis conditions. Furthermore, the optimized method avoids tedious purification steps and is easily conducted on a relatively large-scale using economical and commercially available reagents. 相似文献
154.
155.
Zhao Xiongwen Zhang Siyuan Li Liang Qu Zhaoyan Zhang Yu Ding Yi Liu Junyu 《Wireless Personal Communications》2018,99(1):555-566
Wireless Personal Communications - In this paper, a multi-radio multi-channel (MRMC) assignment algorithm based on topology control and link interference weight for power distribution wireless mesh... 相似文献
156.
采用共沉淀法制备不同物质的量比Mn掺杂的铁基载氧体(Mn-Fe2O3),并进行XRD、BET和TEM表征。开展不同温度下Mn-Fe2O3与CO的化学链燃烧实验,研究载氧体的反应特性,确定较优的掺杂量和反应温度。结果表明,适量的Mn掺杂有助于改善铁基载氧体的反应活性,Fe∶Mn物质的量为50∶1时燃烧反应转化率最高。多循环化学链燃烧实验证实了载氧体稳定性较好。不同升温速率(30、40、50℃/min)下反应动力学分析表明,Mn-Fe2O3与CO的化学链燃烧还原反应均属于随机成核和随后生长的Avrami-Erofeev方程模型,并依据模型分别计算出了该模型的活化能和频率因子。 相似文献
157.
158.
Slow-rise and fast-drop current feature of ultraviolet response spectra for ZnO-nanowire film modulated by water molecules
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This study describes the fabrication of ZnO-nanowire films by electro-chemical anodization of Zn foil.The ZnO films are characterized by field emission scanning electron microscopy,X-ray diffraction patterns,and transmission electron microscopy,respectively.The ultraviolet(UV) photo-response properties of the surface-contacted ZnO film are studied through the current evolution processes under different relative humidities.Unlike the usually observed current spectra of the ZnO films,the drop time is shorter than the rise time.The photo-conductivity gain G and the response time τ are both increased with the increase of the applied bias.The photo-conductivity gain G is lowered with the increase of the environmental humidity,while the response time τ is increased.These results can be explained by considering three different surface processes:1) the electron-hole(e-p) pair generation by the UV light illumination,2) the following surface O2-species desorption,and 3) the photo-catalytic hydrolysis of water molecules adsorbed on the ZnO surface.The slow-rise and fast-drop current feature is suggested to originate from the sponge-like structure of the ZnO nanowires. 相似文献
159.
Back Cover: Improved Electrochromic Performance of Poly(3,4‐ethylenedioxythiophene) by Incorporating a Three‐Dimensionally Ordered Macroporous Structure (Chem. Asian J. 20/2016)
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160.
Direct C—H functionalization of quinoline N-oxides with arylboronic acids is achieved using KMnO_4 as the sole and efficient oxidative system.This method provides an efficient protocol to construct regioselectively 2-arylquinoline N-oxides via radical cross-coupling reaction in moderated to good yields under mild conditions. 相似文献