共查询到20条相似文献，搜索用时 31 毫秒
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磷酸铁锂正极材料具有较高的电势,理论比容量为170 m Ah/g,由于其环境友好,成本低,安全性好,循环性能好等特点,被认为是用于锂离子动力电池的最有希望的正极材料之一。美国威伦斯技术公司是较早对磷酸铁锂进行研究的企业。本文将对威伦斯公司的专利申请进行分析,对其申请现状和技术发展脉络进行介绍。 相似文献
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以Li2CO3和V2O5为原料,用中热固相法制备了掺杂不同氟离子含量的锂离子电池正极材料Li1+xV3O8-yFy,采用XRD衍射对其结构进行表征,并通过充放电测试、循环伏安及电导率测试对其性能进行了研究.测试结果表明,中热固相法制得的Li1+xV3O8-yFy产品较纯,没有杂质相存在;当y=0.1时产品的电化学循环性能最好,首次放电比容量达252.08 mAh/g,以0.2c倍率循环25次之后比容量仍保持在210.93 mAh/g,容量保持率达92.72％. 相似文献
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设计和制备高性能正极材料成为锂离子电池发展的关键。一切影响材料中电子和锂离子传递的因素都会影响到正极材料的性能,其中,材料形貌是决定电子和离子传递路径的关键所在。本文基于近几年报道的正极材料的形貌类型,主要分析了零维、一维、二维和三维形貌的制备方法及不同的形貌对材料可逆容量、循环性能和倍率性能的影响。 相似文献
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《黑龙江科技信息》2020,(26)
Bi2Te3基材料是目前已知的室温附近性能最好的热电材料。但是其热电优值ZT仅趋近于1,对应热电转换效率不足10%,与实际应用的需求相差较远。本文以p型赝三元Bi2Te3基热电材料为研究对象,采用机械合金化方法制备Lu掺杂Bi2Te3基合金粉末,在不同热压温度下制得Bi2Te3基块体样品,意图通过掺杂稀土元素的方式来提高材料的热电性能。对合金化粉体样品进行了XRD物相表征,通过对比烧结前后合金化粉体的XRD衍射图谱,讨论样品的微观结构变化,并进一步验证采用机械合金化方法制备Lu掺杂Bi2Te3基热电材料的可行性。测量了合金化块体样品的导热系数,发现Lu元素掺杂使Bi2Te3基热电材料的导热系数显著降低,最低达到0.1938W/(m·K),有望通过降低导热系数的方式使Bi2Te3基材料的热电性能得到大幅度提高。 相似文献
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In this note, the problem of solution to the matrix equation AX+XTC=B is considered by the Moore-Penrose generalized inverse matrix. A general solution to this equation is obtained. At the same time, some useful conclusions are made, which play important roles in the linear system theories and applications. 相似文献
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The mathematical modeling of most physical systems, such as aerospace systems, heat processes, telecommunication systems, transmission lines and chemical reactors, results in complex high order models. The complexity of the models imposes a lot of difficulties in analysis, simulation and control designs. Several analytical model reduction techniques have been proposed in literature over the past few decades to reduce these difficulties. However, most of the optimal techniques follow computationally demanding, time consuming, iterative procedures that usually result in non-robustly stable models with poor frequency response resemblance to the original high order model in some frequency ranges. Genetic Algorithm (GA) has proved to be an excellent optimization tool in the past few years. Therefore, the aim of this paper will be to use GA to solve H2 and H∞ norm model reduction problems, and help obtain globally optimized nominal models. 相似文献
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We consider robust optimization equilibrium for the bimatrix game based on robust optimization method. In this paper, each player may neither exactly estimate his opponent's strategies nor evaluate his own cost matrix accurately while may estimate a bounded uncertain set. We obtain that the robust optimization equilibrium problem can be formulated as a mixed complementarity problem (MCP) under l1∩l∞-norm. Some numerical examples are presented to illustrate the behavior of robust optimization equilibrium. 相似文献
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基于2000-2019年江西省相关时间序列数据,运用VAR模型分析农业科技创新、技术效率与农业经济发展之间的动态关系。研究结果表明：农业科技创新对农业经济发展的相互效果是正向的,而技术进步对农业经济发展的相互作用结果复杂,在不同时期的作用和方向不一致。相对于技术进步,农业科技创新对农业经济发展的贡献率较大。农业科技创新、农业技术效率与农业经济增长之间存在长期稳定均衡的关系,但农业科技创新投入对农业经济增长的短期影响更为显著。因此,要发挥农业科技创新与技术效率之间的相互促进作用,以科技创新促进农业经济发展,推动农业可持续发展。 相似文献