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991.
Zhang Bo Wang Haiying Yan Xuechao Duan Yu-Ai Guo Shuai Luo Fei-Xian 《Transition Metal Chemistry》2020,45(2):99-110
Transition Metal Chemistry - A series of ruthenium [NNN]- or [NCN]-type complexes (3–7) bearing PPh3 ancillary ligands have been synthesized from pyridine- or phenylene-bridged bis(triazoles)... 相似文献
992.
993.
优化了一种基于表面等离激元银纳米链的马赫-曾德干涉式传感结构.该结构由参考臂、传感臂及纳米线波导构成.纳米线波导由银纳米线包裹一定厚度的硅来构成.引入两条银纳米链分别作为马赫-曾德干涉仪的参考臂和传感臂,并研究所设计结构的传输特性,通过降低传输损耗以提高所设计结构的精确度与灵敏度.相比于两条完全相同的银纳米线作为参考臂和传感臂的情况,在参考臂和传感臂改为银纳米链后,传输特性有明显提高,单位长度损耗明显降低.这是由于银纳米链中的单元结构之间的长程/库仑相互作用增强了结构中的电磁场,进而降低了传输损耗.将两条银纳米链的晶格常数设置为不同的情况,研究发现,在特定的银包硅纳米线的宽度与某些占空比下,含有非对称的银纳米链结构的单位传输损耗小于含有对称的银纳米链结构.由此可以知道,具有小损耗的银纳米颗粒链可以弥补大损耗的银纳米颗粒链的传输损失.利用这个特点,进一步优化设计结构,将一侧银纳米链改为纳米线.改变另一侧银纳米链的晶格常数与占空比,可以发现大多数情况下,这类结构传输特性优于含有两条银纳米链以及含有两条银纳米线的结构.本文的设计结构可以大幅减小传统的马赫-曾德干涉仪的传输损耗,且在结构的制备... 相似文献
994.
Li Xueying Wang Jiangang Duan Fenyan Tao Luwen Xu Teng Chen Lizhuang Yuan Aihua Wang Xiaolong 《Journal of Solid State Electrochemistry》2022,26(1):269-280
Journal of Solid State Electrochemistry - The electrode materials with long cycle life are important for the large-scale application of sodium ion batteries. In this work, P2-type... 相似文献
995.
Zhao Yun-Li Zhang Yue Yuan Xi-Yue Deng Wan-Yuan Zhang Bo Pang Shu-Ting Yin Bing-Yan Wu Hong-Bin Lin Kai-Wen Liu Zhi-Tian Duan Chun-Hui Huang Fei Cao Yong 《高分子科学》2022,40(8):905-913
Chinese Journal of Polymer Science - Polymer solar cells (PSCs) consisting of a polymer donor and a small molecular acceptor is a promising photovoltaic technology, whose device performance is... 相似文献
996.
We study some nonlinear waves in a viscous plasma which is confined in a finite cylinder.By averaging the physical quantities on the radial direction in some cases,we reduce this system to a simple one-dimensional model.It seems that the effects of the bounded geometry(the radius of the cylinder in this case)can be included in the damping coefficient.We notice that the amplitudes of both Korteweg–de Vries(KdV)solitary waves and dark envelope solitary waves decrease exponentially as time increases from the particle-in-cell(PIC)simulation.The dependence of damping coefficient on the cylinder radius and the viscosity coefficient is also obtained numerically and analytically.Both are in good agreement.By using a definition,we give a condition whether a solitary wave exists in a bounded plasma.Moreover,some of potential applications in laboratory experiments are suggested. 相似文献
997.
Mohasan Muhammad Aqeel Anas Bin Lv Pengyu Yang Yantao Duan Huiling 《Acta Mechanica Sinica》2021,37(3):447-455
Acta Mechanica Sinica - In this work, we numerically study the impact of a water droplet onto a deep oil pool. Two fluids are immiscible and the viscosity of the pool liquid is changed... 相似文献
998.
Yue Zhou Ran Duan Xijuan Zhu Jie Wu Jing Ma Xia Li 《Combustion Theory and Modelling》2020,24(5):829-851
Radiative heat transfer plays an important role in the chemical reactions in the combustor. The widely used WSGG model proposed by Smith is established for normal pressure, which shows inevitable computational errors when dealing with radiative heat transfer problems at reduced or elevated pressures. In this paper, an improved global model is established to calculate the radiant energy exchanges between combustion gases and combustor chamber walls. Compared with the Smith model, the new model shows better performance in a wide range of pressure regions. The model accuracy is examined by computing the emissivity, radiative heat flux as well as the radiative source of H2O–CO2 gas mixtures at different pressure values. Finally, the radiative heat transfer inside a 3D TBCC(turbine-based combined cycle) engine exhaust system where strong gradients of pressure and temperature exist, is also addressed. The computational results show that the developed model provides approximate results at much less computational costs than the high-precision MSMGFSK-c8 model, which makes it competitive in complicated combustion systems. 相似文献
999.
Dr. Yueqiang Cao Hao Zhang Dr. Shufang Ji Prof. Zhijun Sui Prof. Zheng Jiang Prof. Dingsheng Wang Prof. Francisco Zaera Prof. Xinggui Zhou Prof. Xuezhi Duan Prof. Yadong Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(28):11744-11749
Atomic regulation of metal catalysts has emerged as an intriguing yet challenging strategy to boost product selectivity. Here, we report a density functional theory-guided atomic design strategy for the fabrication of a NiGa intermetallic catalyst with completely isolated Ni sites to optimize acetylene semi-hydrogenation processes. Such Ni sites show not only preferential acetylene π-adsorption, but also enhanced ethylene desorption. The characteristics of the Ni sites are confirmed by multiple characterization techniques, including aberration-corrected high-resolution scanning transmission electron microscopy and X-ray absorption spectrometry measurements. The superior performance is also confirmed experimentally against a Ni5Ga3 intermetallic catalyst with partially isolated Ni sites and against a Ni catalyst with multi-atomic ensemble Ni sites. Accordingly, the NiGa intermetallic catalyst with the completely isolated Ni sites shows significantly enhanced selectivity to ethylene and suppressed coke formation. 相似文献
1000.
Silicon(Si) materials as anode materials for applications in lithium-ion batteries(LIBs) have received increasing attention.Among the Si materials,the electrochemical properties of SiO_x-based(0x≤2)composites are the most prominent.However,due to the cycling stability of SiO_x being far from practical,there are some problems,such as Iow initial coulombic efficiency(ICE),obvious volume expansion and poor conductivity.Researchers in various countries have optimized the electrochemical properties of SiO_x-based composites by means of pore formation,surface modification,and the choice of constituents.In this review,SiO_x-based composites are classified into three categories based on the valency of Si(SiO_2 composites,SiO composites and SiO_x(0x2) composites).The synthesis,morphologies and electrochemical properties of the SiO_x-based composites that are applied in LIB are discussed.Finally,the prope rties of several common SiO_x-based composites are briefly compared and the challenges faced by SiO_x-based composites are highlight. 相似文献