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排序方式: 共有7764条查询结果,搜索用时 15 毫秒
71.
Xuri Wang Yinglei Wang Ahmad Naveed Guotai Li Hanwei Zhang Yu Zhou Aichun Dou Mingru Su Yunjian Liu Ruiqiang Guo Cheng Chao Li 《Advanced functional materials》2023,33(48):2306205
Layered ammonium vanadate materials exhibit significant mass-specific capacity and ion transport rate due to their small molecular weight and large ionic radius. However, the strong electrostatic interactions of Zn2+ and V–O bonds and the fragile ionic bonding of N-H…O bonds hinder their development. Therefore, this work reports Mg2+ doping NH4V4O10 materials accompanied by flower-like morphology to lower the migration energy barrier and inhibit amine dissolution. Owing to the 3D-flower-like morphology and the combined impact of Mg2+ and structural water, the binding of Zn2+…V-O is significantly enhanced and additional ion channels were constructed. Pre-intercalated Mg2+ enhances the structural integrity and prevents irreversible deammoniation from obtaining excellent cyclic stability. Density functional theory (DFT) calculations show that MNVO provides a smoother Zn2+ diffusion path with a lower migration barrier. Benefited from these advantages, the MNVO cathode exhibits a high specific capacity of 410 mAh g−1 at 0.1 A g−1, satisfactory cyclic stability (90.2 % capacity retention at 10 A g−1 after 5000 cycles), and capable rate ability (118 mAh g−1 at 25 A g−1) within 0.4-1.5 V. Furthermore, the zinc ion storage mechanism in the MNVO cathode is investigated through multiple analyses. 相似文献
72.
“生物医学传感器与测量”课程教学改革探索 总被引:3,自引:0,他引:3
"生物医学传感器与测量"是生物医学工程专业的一门重要专业课。本文针对专业培养目标和课程教学特点,提出兴趣引导,自主学习,实践探索的指导思想,对教学内容和教学方法进行了一系列改革。根据学生的反馈信息,显示改革后获得良好的教学效果,取得了一些有益的探索和尝试。 相似文献
73.
Microstructure evolution and corrosion resistance in simulated CGHAZ of X80 high-deformability pipeline steel 下载免费PDF全文
In this study, the microstructure evolution and corrosion resistance in 0.5M Na2CO3-1 M NaHCO3 solution of X80 high-deformability (X80HD) pipeline steel coarse-grained heat-affected zone (CGHAZ) with several heat input levels were investigated. It is shown that the microstructure of CGHAZ changes from bainite ferrite to granular bainite as the heat input increasing. In addition, the corrosion resistance and the stability of passive film of base material are better than those of CGHAZ with several heat input levels. Too small or too big heat input is inadvisable and better corrosion resistance of CGHAZ is attained when heat input is 30kJ/cm. 相似文献
74.
When a structure material is damaged by impact events, the reliability and lifetime of the material will be severely affected. So impact location is considered as the prime approach for structural health and damage monitoring. In this study, a novel fiber Bragg grating (FBG) impact location system based on broadband light source is designed, aiming at the shortcoming of existing location systems based on FBG. An improved localization algorithm based on the time difference of arrival (TDoA) is proposed for impact location. According to this algorithm, the impact position can be accurately predicted without wave velocity. Impact planar location experiments are carried out for verification of the FBG impact location system and algorithm on a400 mm×400 mm×3 mm aluminum alloy plate. The resulted locating error shows high precision and good stability of the proposed system. This work has been supported by the National Natural Science Foundation of China (Nos.61503218, 61403233, 61573226 and 61473176), the Excellent Young and Middle-Aged Scientist Award Grant of Shandong Province of China (No.BS2013DX018), and the Natural Science Foundation of Shandong Province for Outstanding Young Talents (No.ZR2015JL021). E-mail:pangdan@163.com 相似文献
75.
基于激光诱导荧光的测量原理,研制了一种用于心肌钙蛋白Ⅰ(cTnⅠ)快速检测的便携式系统。首先在测试杯中cTnⅠ与荧光试剂发生免疫反应,经过分离除去多余的荧光试剂,测试杯中的荧光分子与cTnI的量成相关性,通过对荧光分子进行诱导激发,使其发出荧光信号,然后经过光电转换、微弱电信号放大、信号采集与处理,最终实现对cTnⅠ的快速定量检测。临床实验显示,在cTnT为1.5~12.2 ng/mL范围内,本系统与TosohAIA-360生化分析仪的检测结果具有很好的线性关系,样品数为6时两者的相关系数达到0.97。 相似文献
76.
In this paper, we derive the impulse response of a fractional second order filter of the form (s2+as+b)−γ, where a,b?0 and γ>0. The asymptotic properties of the impulse responses are obtained. Moreover, based on the derived analytical impulse response, we show how to perform the discretization of the above fractional second order filter. Finally, a number of illustrated examples in time and frequency domains are provided as proofs of concepts. 相似文献
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79.
本文介绍了一种用于电力系统远动传输规约教学实验的软件系统。该系统利用Visual C++编写完成,模拟了主站和分站之间利用循环式、问答式传输规约进行数据传输的过程,学生可通过上机操作学习不同规约中数据帧(报文)的生成与传输过程,有效改善了专业课的教学效果。 相似文献
80.