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991.
Junping Hu Zhangyin Wang Genrui Zhang Yu Liu Ning Liu Wei Li Jianwen Li Chuying Ouyang Shengyuan A.Yang 《中国物理 B》2021,(4):455-462
When developing high performance lithium-ion batteries,high capacity is one of the key indicators.In the last decade,the progress of two-dimensional(2 D) materials has provided new opportunities for boosting the storage capacity.Here,based on first-principles calculation method,we predict that MnN monolayer,a recently proposed 2 D nodal-loop halfmetal containing the metallic element Mn,can be used as a super high-capacity lithium-ion batteries anode.Its theoretical capacity is above 1554 mA-h/g,more than four times that of graphite.Meanwhile,it also satisfies other requirements for a good anode material.Specifically,we demonstrate that MnN is mechanically,dynamically,and thermodynamically stable.The configurations before and after lithium adsorption exhibit good electrical conductivity.The study of Li diffusion on its surface reveals a very low diffusion barrier(~ 0.12 eV),indicating excellent rate performance.The calculated average open-circuit voltage of the corresponding half-cell at full charge is also very low(~0.22 V),which facilitates higher operating voltage.In addition,the lattice changes of the material during lithium intercalation are very small(~ 1.2%-~4.8%),which implies good cycling performance.These results suggest that 2 D MnN can be a very promising anode material for lithium-ion batteries. 相似文献
992.
Qinghua Liu Xiaoying Wang Andrew Benedict Lusine Janibekyan Stephanie Wong Su Yixian Wang Feimeng Zhou 《Electroanalysis》2019,31(11):2155-2161
Cyclic voltammetry (CV) has been combined with surface plasmon resonance (SPR) for probing electrochemical deposition and redox‐initiated film reorganization and conformational changes. However, the varying potential during CV scans leads to unwanted SPR background changes and complicates interpretation of SPR signals. In this work, we show that, when SPR is coupled with CV, the background correction for underpotential deposition of copper and electropolymerization of aniline is either inaccurate or difficult to perform. For accurate thickness measurements of electrodeposited films, potential‐step (PS) chronoamperometry is a method of choice to combine with SPR. The theory that interprets double‐layer charging is used to explain the advantage of PS chronoamperometry over CV in quantifying the thickness of electrodeposited thin films. The influence of the double‐layer charging on the potential‐induced SPR signal change was analyzed, and the results were used to optimize experimental parameters for PS‐SPR. Overall, PS‐SPR is easier to operate, simpler in data interpretation, and more accurate for the film thickness measurement. 相似文献
993.
Pu Fan Alfaro Clint M. Pirro Valentina Xie Zhuoer Ouyang Zheng Cooks R. Graham 《Analytical and bioanalytical chemistry》2019,411(8):1503-1508
Analytical and Bioanalytical Chemistry - Isocitrate dehydrogenase (IDH) I and II mutations in gliomas cause an abnormal accumulation of 2-hydroxyglutarate (2-HG) in these tumor cells. These... 相似文献
994.
995.
Xinyi Wang Xijun Xu Prof. Jun Liu Zhengbo Liu Jiadong Shen Fangkun Li Prof. Renzong Hu Prof. Lichun Yang Prof. Liuzhang Ouyang Prof. Min Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(49):11486-11493
As anode materials for high-performance Li-ion batteries, peapod-like Ge-based composites, including Ge, a Li-inactive conducting Cu3Ge, and a porous carbon matrix are synthesized simply by annealing CuGeO3@dopamine in a H2/Ar atmosphere. The introduction of the carbon layer and inactive alloying phase Cu3Ge not only enhances the electrical conductivity of the Ge anode, but also reduces the volume change of Ge during the cell cycle as a buffer. In particular, the anode of this peapod-like Cu3Ge/Ge@C shows an excellent long cycle life as well as outstanding capacity performance, with a discharge specific capacity up to 934 mA h g−1 after 500 cycles. 相似文献
996.
Jia‐Xiang Xiang Yao Ouyang Xiu‐Hua Xu Feng‐Ling Qing 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(30):10426-10430
The transformation of a large‐volume industrial by‐product and stable greenhouse gas fluoroform (HCF3) to useful products has recently received significant attention. Now, a simple and scalable preparation of AgCF3 by treatment of HCF3 with t‐BuOK and AgOAc is disclosed. The reactivity of the HCF3‐derived AgCF3 has been demonstrated by hydrotrifluoromethylation of alkenes and C?H trifluoromethylation of (hetero)arenes. This work not only provides a new avenue for the utilization of HCF3, but also presents a reliable and easy‐to‐execute synthesis of the relatively stable AgCF3 solution. 相似文献
997.
介绍了利用现代化管理技术,构建企业营销道德评价指标体系的方法和模式;利用计算机建立企业营销道德测试与评价系统的目标、总体结构以及开发实施方法. 相似文献
998.
提出了一种用于管理信息系统(MIS)的二维报表方法,它根据抽象描述自动生成并具有全屏幕编辑功能,且阐述了软件自动生成工具的设计思路与实现方法。此软件工具面向ORA-CLE,DBASEⅢ,FOXBASE,FOXPRO。 相似文献
999.
钻孔法测量残余应力过程中钻孔附加应变 总被引:3,自引:0,他引:3
本文叙述了钻孔法测量残余应力过程中的附加应变.研究应力水平对附加应变的影响是在单向应力条件下进行的,结果表明,钻孔条件、材料状态以及残余应力达到一定值时,附加应变为零. 相似文献
1000.
因胞壁缺失引起的应力集中问题是蜂窝结构增材制造过程中亟待解决的问题.通过将胞壁缺失所致的缺陷等效成椭圆,基于复变函数方法得到了预测拉伸应力的解析公式和预测弯矩应力的分析方法,进而得到八边形蜂窝结构在双向荷载条件下缺失单行和多行胞壁产生的应力组合值.与有限元结果的对比分析验证了所提理论解析公式的有效性;同时得出距离缺陷最近胞壁上的拉伸应力理论结果与有限元结果吻合良好,弯矩应力的有限元结果与胞壁上的应力梯度呈明显的线性关系.与规则六边形蜂窝在多行缺陷条件下的应力集中问题进行对比,得出八边形蜂窝结构在荷载系数λ=0和λ=1时应力集中程度小于规则六边形蜂窝结构,从而为蜂窝结构增材制造设计提供理论指导. 相似文献