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1.
Cable‐shaped supercapacitors (SCs) have recently aroused significant attention due to their attractive properties such as small size, lightweight, and bendability. Current cable‐shaped SCs have symmetric device configuration. However, if an asymmetric design is used in cable‐shaped supercapacitors, they would become more attractive due to broader cell operation voltages, which results in higher energy densities. Here, a novel coil‐type asymmetric supercapacitor electrical cable (CASEC) is reported with enhanced cell operation voltage and extraordinary mechanical‐electrochemical stability. The CASECs show excellent charge–discharge profiles, extraordinary rate capability (95.4%), high energy density (0.85 mWh cm−3), remarkable flexibility and bendability, and superior bending cycle stability (≈93.0% after 4000 cycles at different bending states). In addition, the CASECs not only exhibit the capability to store energy but also to transmit electricity simultaneously and independently. The integrated electrical conduction and storage capability of CASECS offer many potential applications in solar energy storage and electronic gadgets.  相似文献   
2.
谐波齿轮机构在商业表格印刷机中的应用   总被引:1,自引:1,他引:0  
潘光华 《包装工程》2003,24(3):41-42,55
从商业表格印刷机特殊要求出发,以某一具体机型的传动系统为例,提出采用谐波齿轮机构解决纵向套准的问题。并且分析研究了谐波齿轮机构的工作原理及其在商业表格印刷机中的使用。  相似文献   
3.
Organic conductor is a kind of organic compound which has special electronic and magnetic properties. The research of the organic compounds has received considerable attention because of their potential applications in many areas. The molecular conductive units are theoretically investigated as well as their energy gap and charge distribution. The relationship of conductivity and micro-mechanism is discussed.  相似文献   
4.
In the present work, the prospects and trends of solid electrolyte membrane reactors (SEMRs) towards hydrogen production, are discussed. Initially, an overview of the principles, the properties and the techniques related to the usage of the SEMRs, are presented. In the following, a literature survey covering earlier and recent developments of the various methods (e.g. reforming or partial oxidation or dehydrogenation of hydrocarbons, steam electrolysis) employed in the SEMRs for the production of hydrogen, is performed. Finally, the current status of this research field is analyzed and future research topics are proposed.  相似文献   
5.
将空气中烧成的镍导体用于散热制冷片制作工艺中,可降低成本,提高合格率。通过实验得到的最佳值为:镍导体中4号玻璃(SiO2>30,B2O3>10,PbO<55,TiO2少许)的含量4.5%,化学镀镍时间50min,方阻47.5mΩ/□,附着力8.1N/mm2。  相似文献   
6.
Flexible manufacturing systems (FMSs) are a class of automated systems that can be used to improve productivity in batch manufacturing. Four stages of decision making have been defined for an FMS—the design, planning, scheduling, and control stages. This research focuses on the planning stage, and specifically in the area of scheduling batches of parts through the system.The literature to date on the FMS planning stage has mostly focused on the machine grouping, tool loading, and parttype selection problems. Our research carries the literature a step further by addressing the problem of scheduling batches of parts. Due to the use of serial-access material-handling systems in many FMSs, the batch-scheduling problem is modeled for a flexible flow system (FFS). This model explicitly accounts for setup times between batches that are dependent on their processing sequence.A heuristic procedure is developed for this batch-scheduling problem—the Maximum Savings (MS) heuristic. The MS heuristic is based upon the savings in time associated with a particular sequence and selecting the one with the maximum savings. It uses a two-phase method, with the savings being calculated in phase I, while a branch-and-bound procedure is employed to seek the best heuristic solution in phase II. Extensive computational results are provided for a wide variety of problems. The results show that the MS heuristic provides good-quality solutions.  相似文献   
7.
柳海矿运输大巷返修工程深部软岩支护设计研究   总被引:3,自引:0,他引:3       下载免费PDF全文
通过现场调查、室内试验以及理论分析,柳海矿运输大巷支护现状进行分析研究,总结破坏原因。根据现场工程地质条件、岩石特性和破坏特点,确定软岩变形力学机制为高应力膨胀性软岩,并提出采用预留刚隙柔层支护技术进行支护。  相似文献   
8.
马开连 《齐鲁石油化工》2003,31(2):108-109,118
论述了几种三相交流异步电动机的起动方式及其优缺点 ,介绍了新型的电子软启动方式在我厂深井泵电动机上的应用及取得的运行效果 ,为电动机软启动方式在工矿企业中的应用提供了应用经验。  相似文献   
9.
Evaluating the design of flexible manufacturing systems is complex. Developing a measure of performance useful for evaluating alternate designs continues to be interesting. Here, total productivity of the system is proposed as an appropriate measure. Specification of parameters based upon strategic considerations for this measure are discussed. Finally, the usefulness of the measure is demonstrated through an example.  相似文献   
10.
Y Narahari  R Srigopal 《Sadhana》1996,21(4):415-433
Recently, efficient scheduling algorithms based on Lagrangian relaxation have been proposed for scheduling parallel machine systems and job shops. In this article, we develop real-world extensions to these scheduling methods. In the first part of the paper, we consider the problem of scheduling single operation jobs on parallel identical machines and extend the methodology to handle multiple classes of jobs, taking into account setup times and setup costs. The proposed methodology uses Lagrangian relaxation and simulated annealing in a hybrid framework. In the second part of the paper, we consider a Lagrangian relaxation based method for scheduling job shops and extend it to obtain a scheduling methodology for a real-world flexible manufacturing system with centralized material handling. This research was supported in part by the Office of Naval Research and the Department of Science and Technology grant N00014-93-1017.  相似文献   
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