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71.
72.
Qiang Ma Qi Deng Hang Sheng Wei Ling Hong-Rui Wang Hai-Wen Jiao Xiong-Wei Wu Wen-Xin Zhou Xian-Xiang Zeng Ya-Xia Yin Yu-Guo Guo 《中国科学:化学(英文版)》2018,61(6):732-738
A mild and simple synthesis process for large-scale vanadium redox flow batteries (VRFBs) energy storage systems is desirable. A graphite felt/MnO2 (GF-MNO) composite electrode with excellent electrocatalytic activity towards VO2+/VO2+ redox couples in a VRFB was synthesized by a one-step hydrothermal process. The resulting GF-MNO electrodes possess improved electrochemical kinetic reversibility of the vanadium redox reactions compared to pristine GF electrodes, and the corresponding energy efficiency and discharge capacity at 150 mA cm?2 are increased by 12.5% and 40%, respectively. The discharge capacity is maintained at 4.8 A h L?1 at the ultrahigh current density of 250 mA cm?2. Above all, 80% of the energy efficiency of the GFMNO composite electrodes is retained after 120 charge-discharge cycles at 150 mA cm?2. Furthermore, these electrodes demonstrated that more evenly distributed catalytic active sites were obtained from the MnO2 particles under acidic conditions. The proposed synthetic route is facile, and the raw materials are low cost and environmentally friendly. Therefore, these novel GFMNO electrodes hold great promise in large-scale vanadium redox flow battery energy storage systems. 相似文献
73.
Wetting behavior of a polymer resin used as matrix on fabric surfaces is one of the key attributes for making high quality
structural composites. Though incorporation of various functionalized nanoparticles can stimulate improvements to many properties
of epoxy resins, there has not been any report on wettability of any nano-modified epoxy on rough inclined fabric surfaces.
In this research work, wetting behavior of a previously developed nano-epoxy resin modified by a type of reactive graphitic
nanofibers (r-GNFs) was investigated. The observation results revealed that a unique wetting behavior was discovered from
the nano-epoxy on rough fabric surfaces due to the contribution of the r-GNFs. Based on this dramatically improved wettability
of the epoxy, a concept of dry–wet contact model was proposed to interpret the different wetting phenomenon observed from
the nano-epoxy and that of the pure epoxy. The improved wetting characteristics of the nano-epoxy system will be essential
for enabling future energy efficient infusion processing for manufacturing high quality and high-performance structural composite
applications. 相似文献
74.
75.
以具有不同层数的两亲配合物二[2-(N-十六烷基氨基甲酰基)-8-羟基喹啉]合镧[La(HQ)2Cl]的LB膜为发光层,PBD为电子传输层,制备了双层结构的电致发光(EL)器件:ITO/LB膜/PBD/Al.器件产生黄绿色注入式发光.LB膜的层数和沉积压对器件的性能具有重要影响.在16V激发电压下,5,11和21层LB膜双层EL器件的电流密度分别为48,29和16.4mA/cm2,启亮电压阀值为7.5,8.5和9.5V.器件的亮度随电流密度和驱动电压的增加而增加.在相同偏压下,21层LB膜EL器件的亮度大于5和11层LB膜的器件.在25mN/m沉积的LB膜制备的EL器件具有较高的亮度(1219cd/m2)和击穿电压. 相似文献
76.
77.
WANG Qi YANG Xiaohui JIANG Yanqiu HUO Hang LI Defeng LIN Kaifeng XU Xianzhu 《高等学校化学研究》2018,34(1):13-18
Amino-functionalized porous SiO2 beads with a diameter of 200—800 μm(PSB-NH2) have been successfully synthesized by grafting 3-aminopropyl-triethoxysilane onto meso/macroporous silica beads(PSB), in which the PSB was prepared by hydrothermal synthetic method with a porous hard template anion-exchange resin. The as-prepared materials were characterized by means of nitrogen sorption and transmission electron micrographs(TEM), showing the presence of 3D interconnected and continuous large mesopores and macropores inside. The beads were used to catalyze Knoevenagel condensation and proved to be highly active and selective due to the high accessibility of the reactants to the amino groups via the continuous 3D meso/macopores. Notably, such material in bead format facilitates the extremely straightforward separation from reaction solution without any centrifugation or filtration. Moreover, PSB-NH2 proved to be a stable catalyst via leaching experiment test, and can be easily recovered and reused without significant loss of activity in successive catalytic cycles. 相似文献
78.
以2,5-噻吩二甲酸和稀土盐为原料,通过水热反应,合成了3个稀土金属配位聚合物{[La(OH)(SO4)]}n(1),{[La2(TDC)2(SUC)]}n(2)和{[Gd2(TDC)2(ox)(H_2O)4]·2H_2O}n(3)(H_2TDC=2,5-噻吩二甲酸,SUC=丁二酸,ox=草酸),分别用X射线单晶衍射、元素分析、红外光谱对配合物2和3进行了表征。实验结果表明:配合物2和3均呈现三维网络结构,其中配合物2属于正交晶系,空间群为Pbca,a=1.372 8(4)nm,b=0.704 0(2)nm,c=2.136 2(6)nm,Z=8;配合物3属于单斜晶系,空间群为C2/c,a=1.934 3(4)nm,b=0.990 5(2)nm,c=1.252 8(3)nm,β=107.463(4)°,Z=4。 相似文献
79.
Zhao-hui Li Ye-peng Yu Xuan Lin Jun Chen Hang Zhang Yan-bo Li Huan-huan Wang Qing-hui Meng Rui-rui Sun Xiao-bin Shan Fu-yi Liu Liu-si Sheng 《化学物理学报(中文版)》2018,31(5):619-625
The dissociative photoionization of cyclopentanone was investigated by means of a reflectron time-of-flight mass spectrometer (RTOF-MS) with tunable vacuum ultraviolet synchrotron radiation in the photon energy range of 9.0-15.5 eV. The photoionization efficiency (PIE) curves for molecular ion and fragment ions were measured. The ionization energy of cyclopentanone was determined to be 9.23\begin{document}$\pm$\end{document} 0.03 eV. Fragment ions from the dissociative photoionization of cyclopentanone were identified as C\begin{document}$_5$\end{document} H\begin{document}$_7$\end{document} O\begin{document}$^+$\end{document} , C\begin{document}$_4$\end{document} H\begin{document}$_5$\end{document} O\begin{document}$^+$\end{document} , C\begin{document}$_4$\end{document} H\begin{document}$_8^+$\end{document} /C\begin{document}$_3$\end{document} H\begin{document}$_4$\end{document} O\begin{document}$^+$\end{document} , C\begin{document}$_3$\end{document} H\begin{document}$_3$\end{document} O\begin{document}$^+$\end{document} , C\begin{document}$_4$\end{document} H\begin{document}$_6^+$\end{document} , C\begin{document}$_2$\end{document} H\begin{document}$_4$\end{document} O\begin{document}$^+$\end{document} , C\begin{document}$_3$\end{document} H\begin{document}$_6^+$\end{document} , C\begin{document}$_3$\end{document} H\begin{document}$_5^+$\end{document} , C\begin{document}$_3$\end{document} H\begin{document}$_4^+$\end{document} , C\begin{document}$_3$\end{document} H\begin{document}$_3^+$\end{document} , C\begin{document}$_2$\end{document} H\begin{document}$_5^+$\end{document} and C\begin{document}$_2$\end{document} H\begin{document}$_4^+$\end{document} . With the aid of the ab initio calculations at the \begin{document}$\omega$\end{document} B97X-D/6-31+G(d, p) level of theory, the dissociative mechanisms of C\begin{document}$_5$\end{document} H\begin{document}$_8$\end{document} O\begin{document}$^+$\end{document} are proposed. Ring opening and hydrogen migrations are the predominant processes in most of the fragmentation pathways of cyclopentanone. 相似文献
80.
Yunyun Yang Xilei Cao Hang Luo Xufu Cai 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1557-1566
Lipid nanoparticles, both solid lipid nanoparticles and nanostructured lipid carriers (NLC), containing tacrolimus (FK) were obtained by solvent diffusion method associated with ultrasonication using stearic acid (SA) or beeswax as solid lipid. The oleic acid was used as liquid lipid in the NLC. Lipid nanoparticles were characterized by determining the drug loading, particle size, polydispersity index (PDI) and zeta potential (ZP). Analysis by differential scanning calorimetry and X-ray diffraction were performed. Lipid nanoparticles presented nano-sized from 139 to 275 nm. The PDI results show the particles present from 0.3 to 0.5, and ZP was higher than |25| mV. Drug loading ranged of 2.3–3.2%. SA nanoparticles presented better ZP, average size and distribution. However, beeswax nanoparticles showed higher drug loading. Results suggest there are no incompatibilities between FK and the raw materials. Polymorphic modifications were not observed. The results presented show that lipid nanoparticles using both lipids were successfully obtained and may represent promising delivery system of FK in topical formulations. 相似文献