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971.
972.
Graphene transfer: key for applications 总被引:1,自引:0,他引:1
The first micrometer-sized graphene flakes extracted from graphite demonstrated outstanding electrical, mechanical and chemical properties, but they were too small for practical applications. However, the recent advances in graphene synthesis and transfer techniques have enabled various macroscopic applications such as transparent electrodes for touch screens and light-emitting diodes (LEDs) and thin-film transistors for flexible electronics in particular. With such exciting potential, a great deal of effort has been put towards producing larger size graphene in the hopes of industrializing graphene production. Little less than a decade after the first discovery, graphene now can be synthesized up to 30 inches in its diagonal size using chemical vapour deposition methods. In making this possible, it was not only the advances in the synthesis techniques but also the transfer methods that deliver graphene onto target substrates without significant mechanical damage. In this article, the recent advancements in transferring graphene to arbitrary substrates will be extensively reviewed. The methods are categorized into mechanical exfoliation, polymer-assisted transfer, continuous transfer by roll-to-roll process, and transfer-free techniques including direct synthesis on insulating substrates. 相似文献
973.
974.
We propose an optoelectronic model to investigate polymer solar cells with plasmonic nanoparticles. The optical properties of the plasmonic active layers, approximated by the effective medium theory, are combined with the organic semiconductor model. The simulation suggests the enhancement on short-circuit photocurrent is due to light concentration and redistribution by particle plasmons. 相似文献
975.
Solid-state flexible energy storage devices hold the key to realizing portable and flexible electronic devices. Achieving fully flexible energy storage devices requires that all of the essential components (i.e., electrodes, separator, and electrolyte) with specific electrochemical and interfacial properties are integrated into a single solid-state and mechanically flexible unit. In this study, we describe the fabrication of solid-state flexible asymmetric supercapacitors based on an ionic liquid functionalized-chemically modified graphene (IL-CMG) film (as the negative electrode) and a hydrous RuO(2)-IL-CMG composite film (as the positive electrode), separated with polyvinyl alcohol-H(2)SO(4) electrolyte. The highly ordered macroscopic layer structures of these films arising through direct flow self-assembly make them simultaneously excellent electrical conductors and mechanical supports, allowing them to serve as flexible electrodes and current collectors in supercapacitor devices. Our asymmetric supercapacitors have been optimized with a maximum cell voltage up to 1.8 V and deliver a high energy density (19.7 W h kg(-1)) and power density (6.8 kW g(-1)), higher than those of symmetric supercapacitors based on IL-CMG films. They can operate even under an extremely high rate of 10 A g(-1) with 79.4% retention of specific capacitance. Their superior flexibility and cycling stability are evident in their good performance stability over 2000 cycles under harsh mechanical conditions including twisted and bent states. These solid-state flexible asymmetric supercapacitors with their simple cell configuration could offer new design and fabrication opportunities for flexible energy storage devices that can combine high energy and power densities, high rate capability, and long-term cycling stability. 相似文献
976.
采用恶臭假单胞菌,以活性炭纤维为载体,以聚乙烯醇(PVA)为包埋剂制成固定化恶臭假单胞菌,对含酚废水的降解效果进行研究。与游离恶臭假单胞菌相比,固定化恶臭假单胞菌小球的运行周期长,对苯酚的降解效果好。讨论了外部环境因素包括苯酚的初始质量浓度、pH和温度对固定化恶臭假单胞菌降解苯酚效果的影响。结果表明,随着苯酚质量浓度的增加,固定化恶臭假单胞菌对苯酚具有良好的降解效果;当苯酚初始质量浓度大于200 mg/L时,固定化恶臭假单胞菌降解苯酚的效果远远优越于游离态的;固定化恶臭假单胞菌对高质量浓度的苯酚、pH和温度的变化表现出了较好的耐受力;当pH为7~9,温度在30~35℃,固定化恶臭假单胞菌对苯酚的降解效果达到93%。 相似文献
977.
978.
不锈钢容器及管道的局部腐蚀 总被引:3,自引:0,他引:3
针对在化工行业中局部腐蚀的危险性,本文着重介绍了局部腐蚀中的晶间腐蚀和应力腐蚀发生的条件、机理以及防范的措施。 相似文献
979.
980.
我国21世纪初的天然气工业--扬帆乘风济沧海 总被引:2,自引:0,他引:2
我国天然气工业处于蓬勃发展的青年期,目前开发滞后的主要原因是缺乏长输管线。随着管线的修建和市场的开拓,21世纪储、产量将持续快速增长,形成“四大四中”的天然气工业基地。天然气在一次能源消费构成中将达到8%-10%。 相似文献