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111.
Huang H Yang S Gong J Liu H Duan J Zhao X Zhang R Liu Y Liu Y 《The journal of physical chemistry. B》2005,109(44):20746-20750
We describe a simple method to assemble ZnO nanowires/belts into highly ordered arrays. ZnCu(2) alloy was used as the Zn source, which reacted with water vapor to generate ZnO nanocrystals. The reaction was performed in a mild way, which facilitated the easy control of the reaction conditions. By simply controlling the water bath temperature and carrier gas flux in our experiments, we obtained ZnO nanowires/belts aligned to form ordered arrays. The highly ordered nature of the ZnO arrays is suggested to be related both with the polarities of the H(2)O molecule and the ZnO (0001) surface. Photoluminescence (PL) microscopy revealed that the comblike structures had waveguide properties, where green light enhancement was observed at the tips of the branches. The light enhancement property reveals their promising applications as light source arrays. 相似文献
112.
A novel method: ionic liquid-based ultrasound-assisted extraction of polyphenols from Chinese purple yam 总被引:1,自引:0,他引:1
Junhong Zhang Aizhen Zong Tongcheng Xu Ping Zhan Lina Liu Bin Qiu 《Natural product research》2018,32(7):863-866
Chinese purple yam is famous for therapeutic and nutritional values in lowering blood glucose, blood pressure and even preventing and treating cardiovascular diseases. However, traditional extraction techniques for the functional polyphenolic compounds mostly utilise unfriendly organic solvent and easily cause degradation of polyphenols. In this study, a novel ionic liquid-based ultrasound-assisted extraction (IL-UAE) technique was utilised to obtain polyphenols. The optimal extraction condition included: solid–liquid ratio (0.05 g/mL), ionic liquid concentration (1.05 M), extraction temperature (67°C) and ultrasonic time (37 min). The maximum free radical scavenging activity (86.21%) and total antioxidant activity (2.21 mM) were achieved and matched well with the predicted values, superior to that of the extract from regular ethanol-based UAE. IL-UAE could be a rapid and green technique for efficient extraction of polyphenols from purple yam with low solvent consumption and few structural deterioration, exhibiting application potential in food and pharmaceutical industries. 相似文献
113.
Chunxia Wu Junhong Jia Hongwei Che Jingbo Mu Shufeng Zhao Xiaoliang Zhang 《Surface and interface analysis : SIA》2016,48(10):1056-1061
Nanodot‐textured surface, nanorod‐textured surface and nanocomposite‐textured surface were prepared by the hydrothermal technique and successive ion layer absorption and reaction technique. The adhesion and friction properties of the three kinds of nanotextured surfaces were investigated using an atomic force microscope colloidal probe. Experimental results revealed that the nanorod‐textured surface and nanocomposite‐textured surface can significantly reduce adhesive and friction forces compared with a nanodot‐textured surface. The main reason for this phenomenon was that the nanorod and nanocomposite textures can reduce contact area between the sample surface and the colloidal probe. The effects of surface root mean square roughness, applied load and sliding velocity on the adhesion and friction behaviors of the nanotextured surfaces were investigated. The adhesive and friction forces of the nanotextured surfaces decreased with the increasing surface root mean square roughness. Compared with the nanocomposite‐textured surface, the nanorod‐textured surface has better adhesion and frictional performance. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
114.
This paper proposes a new type of random parameters AACD (RPAACD)
models, which extends the AACD model. Depending on the state of the price process, the
RPAACD models seem to be a valuable alternative to existing approaches and have the better
overall performance. We give the transition probability of the process. Moreover by
employing the transition probability, we obtain the probability properties of the RPACD
model. 相似文献
115.
116.
117.
Junhong Zhang 《Applicable analysis》2013,92(11):1373-1382
This article investigates fourth-order singular p-Laplacian boundary value problems (BVPs), and obtains the necessary and sufficient conditions for existence of positive solutions for fourth-order singular p-Laplacian BVPs on closed interval. 相似文献
118.
In this paper, firstly two examples are given to indicate that the main result in the paper “Characterization of Finite Groups
with Some S-quasinormal Subgroups” (Asaad and Cs?rgő in Monatsh Math 146:263–266, 2005) are not correct. Secondly, a revised version
of that theorem is obtained. 相似文献
119.
Transition metal oxides(TMO) bring a novel direction for the development of energy store materials due to their excellent stability. They not only have high capacity and good cycle performance, but also are cheap and easily available. Zinc oxide(Zn O) as an important part of TMO have gradually attracted attention in the research of electrochemistry. Zn O, as a metal semiconductor with the advantages of wide band gap, possesses high ion migration rate, good chemical stability, simple preparation ... 相似文献
120.
Junhong Ha Shin-ichi Nakagiri Hiroki Tanabe 《Journal of Mathematical Analysis and Applications》2005,310(2):518-532
In this paper we establish the strong Gâteaux differentiability of maps from the set of initial values and forcing terms into the set of solutions for semilinear second-order evolution equations. 相似文献