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991.
Since the high-voltage spinel LiNi0.5Mn1504 (LNMO) is one of the most attractive cathode materials for lithium-ion batteries, how to improve the cycling and rate performance simultaneously has become a critical question. Nanosizing is a typical strategy to achieve high rate capability due to drastically shortened Li- ion diffusion distances. However, the high surface area of nanosized particles increases the side reaction with the electrolyte, which leads to poor cycling performance. Spinels with disordered structures could also lead to improved rate capability, but the cyclability is low due to the presence of Mn3+ ions. Herein, we systematically investigated the synergic interaction between particle size and cation ordering. Our results indicated that a microsized disordered phase and a nanosized ordered phase of LNMO materials exhibited the best combination of high rate capability and cycling performance. 相似文献
992.
酚醛泡沫保温材料在空调系统中的应用 总被引:3,自引:0,他引:3
本文介绍了一种新型酚醛泡沫保温材料,它除具备其他保温材料的优点外,还具有难燃、不含氟利昂、耐化学腐蚀性好、温度适应范围广、抗老化性强、施工方便等优点,是第三代最佳保温材料。另外,酚醛夹芯风管不仅工程安装方便,在经济效益方面也优于其它常用风管,适用于空调系统工程中。 相似文献
993.
Fluorinated Phosphorene: Electrochemical Synthesis,Atomistic Fluorination,and Enhanced Stability 下载免费PDF全文
Xian Tang Weiyuan Liang Jinlai Zhao Zhongjun Li Meng Qiu Taojian Fan Crystal Shaojuan Luo Ye Zhou Yu Li Zhinan Guo Dianyuan Fan Han Zhang 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(47)
Phosphorene has attracted great interest due to its unique electronic and optoelectronic properties owing to its tunable direct and moderate band‐gap in association with high carrier mobility. However, its intrinsic instability in air seriously hinders its practical applications, and problems of technical complexity and in‐process degradation exist in currently proposed stabilization strategies. A facile pathway in obtaining and stabilizing phosphorene through a one‐step, ionic liquid‐assisted electrochemical exfoliation and synchronous fluorination process is reported in this study. This strategy enables fluorinated phosphorene (FP) to be discovered and large‐scale, highly selective few‐layer FP (3?6 atomic layers) to be obtained. The synthesized FP is found to exhibit unique morphological and optical characteristics. Possible atomistic fluorination configurations of FP are revealed by core‐level binding energy shift calculations in combination with spectroscopic measurements, and the results indicate that electrolyte concentration significantly modulates the fluorination configurations. Furthermore, FP is found to exhibit enhanced air stability thanks to the antioxidation and antihydration effects of the introduced fluorine adatoms, and demonstrate excellent photothermal stability during a week of air exposure. These findings pave the way toward real applications of phosphorene‐based nanophotonics. 相似文献
994.
995.
Xiaobing Han Guangyin Jing Xinzheng Zhang Renmin Ma Xuefeng Song Jun Xu Zhimin Liao Ning Wang Dapeng Yu 《Nano Research》2009,2(7):553-557
Reliable ohmic contacts were established in order to study the strain sensitivity of nanowires and nanobelts. Significant
conductance increases of up to 113% were observed on bending individual ZnO nanowires or CdS nanobelts. This bending strain-induced
conductance enhancement was confirmed by a variety of bending measurements, such as using different manipulating tips (silicon,
glass or tungsten) to bend the nanowires or nanobelts, and is explained by bending-induced effective tensile strain based
on the principle of the piezoresistance effect.
This article is published with open access at Springerlink.com 相似文献
996.
Simple image intensity compensation (SIMIC) method prior to application of distortion correction algorithms in brain diffusion Tensor Magnetic Resonance Imaging: Validation test for two cost functions of distortion correction algorithms 下载免费PDF全文
Dong‐Hoon Lee Do‐Wan Lee Bong‐Soo Han 《International journal of imaging systems and technology》2015,25(4):328-333
The purpose of this study is to design a simple image intensity compensation (SIMIC) method prior to the application of a variety of cost functions for distortion correction in diffusion tensor imaging (DTI). The synthetic dataset consists of each direction of diffusion weighted imaging (DWI) made by multiplication of nondiffusion weighted image (b = 0 image) and tensor matrices. We added the effects of patient motion and eddy current distortion using translation, rotation, scaling and shearing matrices. We calculated the b = 0 image of each direction from original DTI, inversely. A co‐registration method was applied to the extracted b = 0 images of each direction based on the original b = 0 image and then, the transformation matrices were generated and the original DTI were transformed using this transformation matrix. For the DTI distortion correction, two kinds of cost functions, normalized mutual information (NMI) and normalized cross‐correlation (NCC), were used. Visual assessments and quantitative measurements were used to evaluate the results. When using the NMI as a cost function, the quantitative results showed no significant differences between NMI and NMI with SIMIC method. However, there are significant differences compared with using the NCC as a cost function. Our study showed cost function for image distortion correction with SIMIC method improved the results both quantitatively and in terms of qualitative accuracy. This method may be helpful for DTI analysis and helpful for increasing accuracy. © 2015 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 25, 328–33, 2015 相似文献
997.
998.
地埋管换热器周围温度场随着运行时间变长不断向远处扩散,地下水流动使得埋管热作用距离沿流动方向大大增加。通过饱和含水层内地埋管换热模型,得到了地下水流动作用下埋管热作用距离的近似表达式,分析了地下水流速、土壤导热系数和孔隙率对热作用距离的影响。借助于地埋管热作用测试平台,分析了地下水流动作用下埋管热作用距离和热恢复特性,结果表明:地下水流动使得埋管热作用距离远大于纯导热模式,且热作用距离在埋管轴向不同埋深处大小不一,建议在地下水流速大于1×10-6m/s的地质区域,沿地下水流动方向设置埋管间距为8~10m。 相似文献
999.
在对于多源不确定性信息进行分析时,需要根据其来源对信息分类.本文研究以证据形式表达的多源信息聚类问题,详细分析证据聚类的评价标准,提出将证据空间向欧氏空间转化,利用硬c-均值聚类法对多源不确定性信息聚类.基于以上理论,给出一个利用多源传感器ESM实现空中目标跟踪的实例. 相似文献
1000.
介绍了18万t/a甲醇合成系统原始开车前的准备工作、开车过程及开车过程中触媒升温还原的注意事项,分析了原始开车过程中出现的主要问题,并介绍了相应的解决方法。 相似文献