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991.
992.
Nana Liu Hui Qiao Kang Xu Yilian Xi Long Ren Ningyan Cheng Dandan Cui Xiang Qi Xun Xu Weichang Hao Shi Xue Dou Yi Du 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(23)
As a rising star in the family of graphene analogues, germanene shows great potential for electronic and optical device applications due to its unique structure and electronic properties. It is revealed that the hydrogen terminated germanene not only maintains a high carrier mobility similar to that of germanene, but also exhibits strong light–matter interaction with a direct band gap, exhibiting great potential for photoelectronics. In this work, few‐layer germanane (GeH) nanosheets with controllable thickness are successfully synthesized by a solution‐based exfoliation–centrifugation route. Instead of complicated microfabrication techniques, a robust photoelectrochemical (PEC)‐type photodetector, which can be extended to flexible device, is developed by simply using the GeH nanosheet film as an active electrode. The device exhibits an outstanding photocurrent density of 2.9 µA cm?2 with zero bias potential, excellent responsivity at around 22 µA W?1 under illumination with intensity ranging from 60 to 140 mW cm?2, as well as short response time (with rise and decay times, tr = 0.24 s and td = 0.74 s). This efficient strategy for a constructing GeH‐based PEC‐type photodetector suggests a path to promising high‐performance, self‐powered, flexible photodetectors, and it also paves the way to a practical application of germanene. 相似文献
993.
Xi-Ke Gao Jian-Min Dou Feng-Ying Dong Da-Cheng Li Da-Qi Wang 《Journal of Inorganic and Organometallic Polymers and Materials》2004,14(4):227-237
A novel 2D network complex [K(N18C6)]2(CH3CN) [Ni(mnt)2] (1) (where N18C6 = 2,3-naphtho-18-crown-6 and mnt = maleonitriledithiolate) has been synthesized and characterized by elemental analysis, FT-IR spectrum, UV-visible spectrum and single crystal X-ray diffraction. The complex molecules are linked into 1D chains by the bridging CH3CN molecules through weak K-N interactions and the result chains are assembled into a novel 2D network through the inter-chain π–π stacking interactions occurred between adjacent naphthylene moieties of N18C6. The cyclic voltammogram of the title complex displays a reversible process corresponding to the [Ni(mnt)2]?/[Ni(mnt)2]2? reaction. 相似文献
994.
讨论了结构实验系统软件的设计与实现.整个系统采用两层结构,前端设置一台工控一体工作站,负责处理与底层控制装置的通讯.后台机接收到工控一体工作站的数据包后,及时对数据进行处理. 相似文献
995.
Chaozhu Shu Jianping Long Shi‐Xue Dou Jiazhao Wang 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(6)
High‐performance flexible lithium–oxygen (Li–O2) batteries with excellent safety and stability are urgently required due to the rapid development of flexible and wearable devices. Herein, based on an integrated solid‐state design by taking advantage of component‐interaction between poly(vinylidene fluoride‐co‐hexafluoropropylene) and nanofumed silica in polymer matrix, a stable quasi‐solid‐state electrolyte (PS‐QSE) for the Li–O2 battery is proposed. The as‐assembled Li–O2 battery containing the PS‐QSE exhibits effectively improved anodic reversibility (over 200 cycles, 850 h) and cycling stability of the battery (89 cycles, nearly 900 h). The improvement is attributed to the stability of the PS‐QSE (including electrochemical, chemical, and mechanical stability), as well as the effective protection of lithium anode from aggressive soluble intermediates generated in cathode. Furthermore, it is demonstrated that the interaction among the components plays a pivotal role in modulating the Li‐ion conducting mechanism in the as‐prepared PS‐QSE. Moreover, the pouch‐type PS‐QSE based Li–O2 battery also shows wonderful flexibility, tolerating various deformations thanks to its integrated solid‐state design. Furthermore, holes can be punched through the Li–O2 battery, and it can even be cut into any desired shape, demonstrating exceptional safety. Thus, this type of battery has the potential to meet the demands of tailorability and comformability in flexible and wearable electronics. 相似文献
996.
Xiaoyu Hu Yuanyuan Dou Jingjing Li Zunfeng Liu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(32)
Wearable electronics have attracted a tremendous amount of attention due to their many potential applications, such as personalized health monitoring, motion detection, and smart clothing, where electronic devices must conformably form contacts with curvilinear surfaces and undergo large deformations. Structural design and material selection have been the key factors for the development of wearable electronics in the recent decades. As one of the most widely used geometries, buckling structures endow high stretchability, high mechanical durability, and comfortable contact for human–machine interaction via wearable devices. In addition, buckling structures that are derived from natural biosurfaces have high potential for use in cost‐effective and high‐grade wearable electronics. This review provides fundamental insights into buckling fabrication and discusses recent advancements for practical applications of buckled electronics, such as interconnects, sensors, transistors, energy storage, and conversion devices. In addition to the incorporation of desired functions, the simple and consecutive manipulation and advanced structural design of the buckled structures are discussed, which are important for advancing the field of wearable electronics. The remaining challenges and future perspectives for buckled electronics are briefly discussed in the final section. 相似文献
997.
Pengyi Lu Xiaowei Wang Lei Wen Xiaotong Jiang Wenlei Guo Lei Wang Xiao Yan Feng Hou Ji Liang Hui‐Ming Cheng Shi Xue Dou 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(15)
An effective, nondestructive, and universal strategy to homogeneously modify freestanding carbon nanotube (CNT) films with various active species is essential to achieve functional electrodes for flexible electrochemical energy storage, which is challenging and has attracted considerable research interest. In this work, a generalizable concept, to utilize silicon oxide as the intermediate to uniformly decorate various metal sulfide nanostructures throughout CNT films is reported. Taking nickel sulfide nanosheet/CNT (NS/CNT) films, in which the NS nanosheets are homogeneously attached on the intact few‐walled CNTs, as an example, the sheet‐like NS provides sufficient active sites for redox reactions and the CNT network acts as an efficient electron highway, maintaining the structural integrity of the composite and also buffering volume changes. These merits enable NS/CNT films to meet the requirements of versatile energy storage applications. When used for supercapacitors, a high specific capacitance (2699.7 F g?1/10 A g?1), outstanding rate performance at extremely high rates (1527 F g?1/250 A g?1), remarkable cycling stability, and excellent flexibility can be achieved, among the best performance so far. Moreover, it also delivers excellent performance in the storage of Li and Na ions, meaning it is also potentially suitable for Li/Na ion batteries. 相似文献
998.
In Situ Exfoliated,Edge‐Rich,Oxygen‐Functionalized Graphene from Carbon Fibers for Oxygen Electrocatalysis 下载免费PDF全文
Zhijuan Liu Zhenghang Zhao Yanyong Wang Shuo Dou Dafeng Yan Dongdong Liu Zhenhai Xia Shuangyin Wang 《Advanced materials (Deerfield Beach, Fla.)》2017,29(18)
Metal‐free electrocatalysts have been extensively developed to replace noble metal Pt and RuO2 catalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) in fuel cells or metal–air batteries. These electrocatalysts are usually deposited on a 3D conductive support (e.g., carbon paper or carbon cloth (CC)) to facilitate mass and electron transport. For practical applications, it is desirable to create in situ catalysts on the carbon fiber support to simplify the fabrication process for catalytic electrodes. In this study, the first example of in situ exfoliated, edge‐rich, oxygen‐functionalized graphene on the surface of carbon fibers using Ar plasma treatment is successfully prepared. Compared to pristine CC, the plasma‐etched carbon cloth (P‐CC) has a higher specific surface area and an increased number of active sites for OER and ORR. P‐CC also displays good intrinsic electron conductivity and excellent mass transport. Theoretical studies show that P‐CC has a low overpotential that is comparable to Pt‐based catalysts, as a result of both defects and oxygen doping. This study provides a simple and effective approach for producing highly active in situ catalysts on a carbon support for OER and ORR. 相似文献
999.
1000.
本文以通用交直流传动系统CAD软件包为背景,引入分数时滞模型及其辨识方法,分别辨识交直流传动系统的离散模型,并能求得其对应的连续模型,这为利用工程设计方法,自适应地设计控制器提供了方便。另外,本软件包所提供的方便的图形界面,明显的辨识结果比较,也为自动控制系统工程设计方法的学习提供了很好的CAI手段。 相似文献