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71.
72.
溶胶-凝胶法制备高c轴取向纳米V_2O_5薄膜 总被引:1,自引:0,他引:1
采用溶胶-凝胶法,以二乙酰丙酮氧钒(VO(C5H7O2)2)为前驱物,通过提拉方式,在预镀非晶SiO2薄膜的硼硅玻璃上制备多晶纳米五氧化二钒(V2O5)薄膜。通过X射线衍射、傅里叶变换红外吸收光谱、紫外-可见-近红外光谱等表征手段对不同热处理条件下的样品进行了结构和光学性能分析。结果表明,热处理温度在350~550℃,无论是在空气中还是在氧分压为0.1Pa的氮气中,均能得到高c轴取向生长的纳米V2O5薄膜,结晶性能良好,晶粒尺寸分布在21~45nm,样品在810cm-1和1026cm-1附近存在对应于5价钒氧化物的红外吸收峰,在500nm出现强烈的带间吸收。与现有的溶胶-凝胶法相比,本实验选用的VO(C5H7O2)2是制备高c轴生长、结晶性好的纳米V2O5薄膜的理想前驱物。 相似文献
73.
Jingsheng Cai Jia Jin Zhaodi Fan Chao Li Zixiong Shi Jingyu Sun Zhongfan Liu 《Advanced materials (Deerfield Beach, Fla.)》2020,32(50):2005967
Lithium–sulfur (Li–S) batteries have heretofore attracted tremendous interest due to low cost and high energy density. In this realm, both the severe shuttling of polysulfide and the uncontrollable growth of dendritic lithium have greatly hindered their commercial viability. Recent years have witnessed the rapid development of rational approaches to simultaneously regulate polysulfide behaviors and restrain lithium dendritic growth. Nevertheless, the major obstacles for high-performance Li–S batteries still lie in little knowledge of bifunctional material candidates and inadequate explorations of advanced technologies for customizable devices. Herein, a “two-in-one” strategy is put forward to elaborate V8C7–VO2 heterostructure scaffolds via the 3D printing (3DP) technique as dual-effective polysulfide immobilizer and lithium dendrite inhibitor for Li–S batteries. A thus-derived 3DP-V8C7–VO2/S electrode demostrates excellent rate capability (643.5 mAh g−1 at 6.0 C) and favorable cycling stability (a capacity decay of 0.061% per cycle at 4.0 C after 900 cycles). Importantly, the integrated Li–S battery harnessing both 3DP hosts realizes high areal capacity under high sulfur loadings (7.36 mAh cm−2 at a sulfur loading of 9.2 mg cm−2). This work offers insight into solving the concurrent challenges for both S cathode and Li anode throughout 3DP. 相似文献
74.
Carbon‐Coated Li3VO4 Spheres as Constituents of an Advanced Anode Material for High‐Rate Long‐Life Lithium‐Ion Batteries
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Laifa Shen Shuangqiang Chen Joachim Maier Yan Yu 《Advanced materials (Deerfield Beach, Fla.)》2017,29(33)
Lithium‐ion batteries are receiving considerable attention for large‐scale energy‐storage systems. However, to date the current cathode/anode system cannot satisfy safety, cost, and performance requirements for such applications. Here, a lithium‐ion full battery based on the combination of a Li3VO4 anode with a LiNi0.5Mn1.5O4 cathode is reported, which displays a better performance than existing systems. Carbon‐coated Li3VO4 spheres comprising nanoscale carbon‐coating primary particles are synthesized by a morphology‐inheritance route. The observed high capacity combined with excellent sample stability and high rate capability of carbon‐coated Li3VO4 spheres is superior to other insertion anode materials. A high‐performance full lithium‐ion battery is fabricated by using the carbon‐coated Li3VO4 spheres as the anode and LiNi0.5Mn1.5O4 spheres as the cathode; such a cell shows an estimated practical energy density of 205 W h kg?1 with greatly improved properties such as pronounced long‐term cyclability, and rapid charge and discharge. 相似文献
75.
Laser Protection with VO_2 Film 总被引:1,自引:0,他引:1
LaserProtectionwithVO2FilmZHAZizhongZHANGYundongWANGQi(查子忠)(张蕴东)(王琪)(InstituteofOptoelectronics,HarbinInstituteofTechnology,H... 相似文献
76.
网格环境中基础教育资源共享模型研究 总被引:3,自引:0,他引:3
针对传统基础教育资源共享存在着信息孤岛,缺乏有效组织管理的问题,提出了一个基于网格的基础教育资源共享模型,包括系统组织模型与系统体系结构。该模型根据我国中小学校实际分布情况,利用虚拟组织(VO)构建了一个层次化的信息集成系统。设计并分析了其面向广域教育资源共享和协作的模块化系统体系结构。资源查找、资源调度等资源管理关键技术也在文中进行了分析讨论。 相似文献
77.
结合VBE中VO业务过程和迁移工作流规范的系统架构,提出以VBE为联盟组织域的迁移工作流系统模型,给出了一种基于成员组织自治管理和服务市场招标相结合的服务发现模式,并对描述了基于迁移工作流的VO管理流程。该模型在VBE中实现VO的方式具有组建速度快、通信代价低、运行效率高和业务适用范围广等优点。 相似文献
78.
79.
CAI Lili CHEN Hongjian LI Yangxian CHEN Guifeng LI Xinghua HAO Jiangang ZHANG Yu 《稀有金属(英文版)》2006,25(Z2)
The oxygen-related defects in CZ silicon during electron irradiation (1.5 MeV) and subsequent annealing in the range of 150-600 ℃ were investigated by means of FTIR.In the electron irradiation CZ-Si, vacancy-oxygen complex is one of the dominant defects and its concentration is proportional to electron dose but not related to oxygen concentration.In this work, it was focused on the identification of the weak band at 860 cm-1 which was originated from asymmetrical stretching vibrations of an oxygen atom in the negative VO complex.It exhibits the same thermal stability with neutral VO band at 830 cm-1.In addition, the intensity of 889 cm-1 band has never been observed to exceed that of the A-center, implying that only a partial transformation of VO into VO2 does occur. 相似文献
80.
本文介绍了基于服务网格的地理信息协同标注系统的体系结构,描述了信息服务网格中的一种新型协同标注系统的架构,并重点讨论了地理信息协同标注系统如何与信息服务网格结合和虚拟组织在系统中的体现形式。 相似文献