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金属-介质-金属结构的超表面窄带吸收器应用广泛,但金属固有的欧姆损耗会导致吸收峰的半高全宽偏大,影响吸收器在传感领域的应用。本文用介质顶层结构取代超表面的金属顶层结构,设计了一种介质-介质-金属结构的混合超表面窄带吸收器。吸收器由Al2O3倒圆台顶层阵列、SiO2中间介质层以及银膜基底组成,通过有限元法对吸收器的吸收光谱进行仿真,结果显示吸收器在可见光波段产生最大吸收率为99.88%、半高全宽为2.26 nm的吸收峰。通过与相同尺寸参数的金属-介质-金属超表面窄带吸收器进行吸收光谱和吸收峰处电场分布的对比,分析两种结构不同的吸收原理。同时对混合超表面窄带吸收器尺寸参数对吸收峰的影响,吸收器对外界折射率的传感性能进行仿真和分析,为该结构吸收器的可调性和稳定性,以及在折射率传感上的应用提供参考。 相似文献
3.
Huanqing Liu Xu Gao Jun Chen Jinqiang Gao Haoji Wang Yu Mei Huan Liu Wentao Deng Guoqiang Zou Hongshuai Hou Xiaobo Ji 《Journal of Energy Chemistry》2022,(12):478-485
P2-type Mn-based layered oxides are viewed as promising cathode materials for sodium ion battery by virtue of their high theoretical capacity. Considering that pure Na2/3MnO2 suffers from poor cycling performances, Cu-substitution strategy is proposed to effectively alleviate this issue. However, the structural evolution mechanism of the Cu-containing samples still remains unclear. Herein, we propose that CuSubstitution P2-type Na0.66Mn1-xCux 相似文献
4.
Jaeyoung Kim Wontae Lee Jangwhan Seok Eunkang Lee Woosung Choi Hyunyoung Park Soyeong Yun Minji Kim Jun Lim Won-Sub Yoon 《Journal of Energy Chemistry》2022,(3):226-236
All-solid-state batteries offer an attractive option for developing safe lithium-ion batteries. Among the various solid-state electrolyte candidates for their applications, sulfide solid electrolytes are the most suitable owing to their high ionic conductivity and facile processability. However, their performance is extensively lower compared with those of conventional liquid electrolyte-based batteries mainly because of interfacial reactions between the solid electrolytes and high capacity cath... 相似文献
5.
Shuang-Jing Zhou Xiao Cheng Chun-Xia Hu Guo-Yong Xu Wen-Jing Xiao Jun Xuan 《中国科学:化学(英文版)》2021,(1):61-65
A formal[4+3]-cycloaddition reaction of ortho-hydroxyphenyl-substituted para-quinone methides(p-QMs)with in-situ generated azaoxyallyl cations is reported.The reaction occurs under very mild reaction conditions(transition-metal free,room temperature,cheap inorganic base)and provides a very efficient route to a series of biologically important 1,4-benzoxazepine derivatives in good to excellent yields. 相似文献
6.
For the birth–death Q-matrix with regular boundary, its minimal process and its maximal process are closely related. In this paper, we obtain the uniform decay rate and the quasi-stationary distribution for the minimal process. And via the construction theory, we mainly derive the eigentime identity and the distribution of the fastest strong stationary time(FSST) for the maximal process. 相似文献
7.
The thermal decomposition of Zn-MPA complex was investigated under microwave irradiation. ZnO and ZnS nanocrystals could be obtained by decomposing Zn-MPA(3-mercaptopropionic acid) complex under different reaction conditions. It was found that both the pH value of the solution and the molar ratio of Zn2+ and MPA can play an important role in the formation of ZnO and ZnS nanocrystals. MPA mainly acts as an S source or as a complexing agent. This study provides a new route for the controllable preparation of semiconductor nanocrystals. 相似文献
8.
Xue-Ru Wu Zhi-Kun Liu Min Zeng Ming-Xing Chen Jun Tao Shu-Qi Wu Hui-Zhong Kou 《中国科学:化学(英文版)》2022,(8):1569-1576
Synergistic fluorescent spin crossover(SCO) bifunctional molecular materials have novel applications in the molecule-based magneto-optical switches. Herein, we report two novel three-dimensional(3D) Hofmann-type fluorescent SCO complexes [Fe~Ⅱ-(tppe)MI(CN)2]Cl O4·n Solv(tppe = tetra-(4-pyridylphenyl)ethene, M = Ag(tppe-Ag), Au(tppe-Au)). Both complexes show one-step abrupt SCO with the transition temperature of 230 K for tppe-Ag, and 245 K for tppe-Au accompanied by a color... 相似文献
9.
An understanding of the particle transport characteristics in a branched network helps to predict the particle distribution and prevent undesired plugging in various engineering systems.Quantitative analysis of particle flow characteristics is challenging in that experiments are expensive and particle flow is difficult to detect without disturbing the flow.To overcome this difficulty,man-made fractal tree-like branched networks were built,and a coupled computational fluid dynamic and discrete element method model was applied.A series of numerical simulations was carried out to analyze the influence of fractal structure parameters of networks on the particle flow characteristics.The joint influence of inertial,shunt capacity and superposition from upstream branches on particle flow was investigated.The injection position at the inlet determined the particle velocity and its future flow path.The particle density ratio,particle size and bifurcation angle had a greater influence on the shunting of K2 branches than that in the K1 level and Nk22/Nk21 reached a maximum at 60°.Compared with a network with an even number of branches,there was a preferential branch when the branch number was odd.The preferential branch effect or asymmetry degree of the level(K2)branches had a more significant impact on particle shunting than that from the upstream branches(K1). 相似文献
10.
Two-dimensional van der Waals magnetic materials are intriguing for applications in the future spintronics devices, so it is crucial to explore strategy to control the magnetic properties. Here, we carried out first-principles calculations and Monte Carlo simulations to investigate the effect of biaxial strain and hydrostatic pressure on the magnetic properties of the bilayer CrI3. We found that the magnetic anisotropy, intralayer and interlayer exchange interactions, and Curie temperature can be tuned by biaxial strain and hydrostatic pressure. Large compressive biaxial strain may induce a ferromagneticto-antiferromagnetic transition of both CrI3 layers. The hydrostatic pressure could enhance the intralayer exchange interaction significantly and hence largely boost the Curie temperature. The effect of the biaxial strain and hydrostatic pressure revealed in the bilayer CrI3 may be generalized to other two-dimensional magnetic materials. 相似文献