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11.
Investigation on a new electrospun gel polymer electrolyte consisting of thermoplastic polyurethane (TPU) and poly(vinylidene fluoride) (PVdF) has been made. Its characteristics were investigated by scanning electron microscopy, FT-IR, Differential Scanning Calorimeter (DSC) analysis. This kind of gel polymer electrolyte had a high ionic conductivity about 3.2 × 10− 3 S cm− 1 at room temperature, and exhibited a high electrochemical stability up to 5.0 V versus Li+/Li, good mechanical strength and stability to allow safe operation in rechargeable lithium-ion polymer batteries. A Li/GPE/LiFePO4 cell delivered a high discharge capacity when it was evaluated at 0.1 °C—rate at 25 °C (167.8 mAh g− 1). And a very stable cycle performance also existed under this low current density. 相似文献
12.
Carbon aerogel (CA) microspheres have been successfully synthesized by an inverse emulsion polymerization and characterized by scanning electron microscopy (SEM), N2 sorption isotherm and X-ray diffraction (XRD). The results show that the size and pore characteristics of carbon microsphere obviously depend on stirring speed and concentration of surfactant in the emulsion polymerization process. The resultant CA microspheres are amorphous carbon structure with the size ranging from about 2 to 50 μm by changing the stirring speed. CA microspheres with SBET of 414-603 m2 g− 1 and Vmeso of 0.028-0.432 cm3 g− 1 are synthesized using different SPAN80 concentrations. The results of cyclic voltammetry indicate that the CA microspheres prepared at a stirring speed of 480 rpm and at Vs/Vh = 0.01 have ideal supercapacitive behavior in 6 M KOH electrolyte, the maximum specific capacitance of the electrode reaches 180 F g− 1. 相似文献
13.
Yuchu Liu Huanyu Lei Qing-Yun Guo Xianyou Liu Xinghan Li Yuean Wu Weiyi Li Wei Zhang Geng Xin Liu Xiao-Yun Yan Stephen Z.D.Cheng 《高分子科学》2023,41(5):607-620
The construction of complex superlattices using homogenous soft matter has great potential for the bottom-up fabrication of complex, nanoscale structures. This topic is not only interested in scientific exploring for new concepts of supramolecular crystals with nanometer in sizes, which is about thousand times larger in volumes than those of normal crystals, but also practically important to provide construction principles of metamaterials which are artificially structured materials for controll... 相似文献
14.
本阐明了JP3—1型示波极谱仪电源及显示系统的工作原理,并举例说明这两部分的故障维修。 相似文献
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16.
Yi Lanhua Hu You Fei Junjie Li Juan Yang Chunguang Wang Xianyou 《Journal of Solid State Electrochemistry》2019,23(6):1739-1748
Journal of Solid State Electrochemistry - Pd/C and Pd-Co/C nanocatalysts are prepared via a simple and environmentally friendly method and are used as anodic catalyst for direct... 相似文献
17.
为满足快信号测试要求,提出了利用滤波器原理设计补偿器来提高传输线带宽,以减小信号在传输过程中的畸变和损失。针对强光一号加速器测试电缆特性,设计制作了小型化的带宽补偿器。通过采用该电缆补偿技术,强光一号加速器测量电缆补偿后的传输带宽达到200 MHz,幅度为原始信号的1/3,满足了强光一号加速器测试电缆快信号传输的要求。给出了原始信号、未补偿信号及补偿后信号的比较结果,证明补偿后的信号明显比未补偿信号更接近原始信号,原始信号经电缆传输后造成的前沿损失和波形畸变通过带宽补偿器后获到了明显的补偿和修复。编制了专用补偿器设计软件,使补偿器初期设计中的极零对寻找、元器件参数计算等工作实现自动化。 相似文献
18.
A flash lamp pumped 2.09 μm Cr, Tm, Ho:YAG laser utilizing a self-grown La(3)Ga(5)SiO(14) crystal as the electro-optic Q-switch generator is proposed and demonstrated for the first time. Operating at 3 Hz repetition rate, 520 mJ pulse energy with 35 ns pulse width is achieved by optimizing the Q-switch delay time and compensating for the thermal depolarization with a quarter-wave plate. The corresponding peak power is 14.86 MW, and the Q-switched-to-normal-mode energy extraction efficiency is 66.3%. To our knowledge, this Q-switched giant pulse is the best result reported to date in 2.09 μm laser resonator. 相似文献
19.
用微量量热计测定了在室温至600 K范围内吡啶在NaY、CaY、R_EY和HY这几种Y型沸石上的吸附热。实验结果表明, 在这四种沸石上, 存在两种不同类型的酸中心, 一种是B酸中心; 另一种是非活化的L酸中心。B酸中心的酸强度随温度的升高而增加, 而非活化的L酸中心则随温度的升高而减小。在NaY沸石表面上, 只有Na~+一种非活化的L酸中心; 在HY沸石表面上则只有一种B酸中心。在R_EY和CaY表面上, 同时存在着B酸中心和非活化的L酸中心。高温时, 吡啶先吸附在强酸中心H~+上。室温时吡啶在所有试样上的吸附量均在3.0~3.2 mmolg~(-1)之间, 该值正好对应于超笼和β笼中的吸附中心数。 相似文献
20.
2,2-二羟甲基-1,3-丙二醇单缩醛的合成 总被引:2,自引:0,他引:2
引言2,2-二羟甲基-1,3-丙二醇(以下称季戊四醇)单缩醛是有机合成的重要中间体。我们曾用季戊四醇单缩醛与氢化钠及1,3-丙磺内酯反应合成了一系列含有1,3-二氧六环的磺酸盐型可断裂表面活性剂[1]。目前,有关季戊四醇单缩醛的文献报道极少。Conr... 相似文献